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Epicyclic gearing

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planets have "timing marks" (or "relative gear mesh phase" in technical term). The assembly conditions of compound planetary gears are more restrictive than simple planetary gears, and they must be assembled in the correct initial orientation relative to each other, or their teeth will not simultaneously engage the sun and ring gear at opposite ends of the planet, leading to very rough running and short life. In 2015, a traction based variant of the "stepped-planet" design was developed at the Delft University of Technology, which relies on compression of the stepped planet elements to achieve torque transmission. The use of traction elements eliminates the need to "timing marks" as well as the restrictive assembly conditions as typically found. Compound planetary gears can easily achieve larger transmission ratio with equal or smaller volume. For example, compound planets with teeth in a 2:1 ratio with a 50T ring gear would give the same effect as a 100T ring gear, but with half the actual diameter.
152: 5195:. Idler gears are used between sun gear and the planets to cause the sun gear to rotate in the same direction as the ring gear when the planet carrier is stationary. At low input speed, because of the load on the output, the sun will be stationary and the planet carrier will rotate in the direction of the ring gear. Given a high enough load, the turbine of the torque converter will remain stationary, the energy will be dissipated and the torque converter pump will slip. If the input speed is increased to overcome the load the converter turbine will turn the output shaft. Because the torque converter itself is a load on the planet carrier, a force will be exerted on the sun gear. Both the planet carrier and the sun gear extract energy from the system and apply it to the output shaft. 129:, which meshes with the planet gears. Planetary gears (or epicyclic gears) are typically classified as simple or compound planetary gears. Simple planetary gears have one sun, one ring, one carrier, and one planet set. Compound planetary gears involve one or more of the following three types of structures: meshed-planet (there are at least two more planets in mesh with each other in each planet train), stepped-planet (there exists a shaft connection between two planets in each planet train), and multi-stage structures (the system contains two or more planet sets). Compared to simple planetary gears, compound planetary gears have the advantages of larger reduction ratio, higher torque-to-weight ratio, and more flexible configurations. 4585: 5351: 5237:
wear quickly and sometimes crack. But the planetary speed reducer has multiple gear contacting surfaces with a larger area that can distribute the loading evenly around the central axis. Multiple gear surfaces share the load, including any instantaneous impact loading, evenly, which makes them more resistant to damage from higher torque. The housing and bearing parts are also less likely to be damaged from high loading as only the planet carrier bearings experience significant lateral force from the transmission of torque, radial forces oppose each other and are balanced, and axial forces only arise when using helical gears.
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is a convenient way to distinguish the sun gears of the two epicyclic gear trains. Ring gears are normally fixed in most applications as this arrangement will have a good reduction capacity. The second sun gear serves the same purpose as the ring gear of a simple planetary gear train but clearly does
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If one is to create an asymmetric carrier frame with non-equiangular planet gears, say to create some kind of mechanical vibration in the system, one must make the teething such that the above equation complies with the "imaginary gears". For example, in the case where a carrier frame is intended to
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Epicyclic gearing is also available which consists of a sun, a carrier, and two planets which mesh with each other. One planet meshes with the sun gear, while the second planet meshes with the ring gear. For this case, when the carrier is fixed, the ring gear rotates in the same direction as the sun
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In a typical application, the drive power connects to the sun gear. The sun gear then drives the planetary gears assembled with the external gear ring to operate. The whole set of planetary gear system revolves on its own axis and along the external gear ring where the output shaft connected to the
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gear, where a very high reduction ratio in a small package was needed. This had two outer ring gears, each half the thickness of the other gears. One of these two ring gears was held fixed and had one tooth fewer than did the other. Therefore, several turns of the "sun" gear made the "planet" gears
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Some epicyclic gear trains employ two planetary gears which mesh with each other. One of these planets meshes with the sun gear, the other planet meshes with the ring gear. This results in different ratios being generated by the planetary and also causes the sun gear to rotate in the same direction
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Some designs use "stepped-planet" which have two differently-sized gears on either end of a common shaft. The small end engages the sun, while the large end engages the ring gear. This may be necessary to achieve smaller step changes in gear ratio when the overall package size is limited. Compound
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that form epicyclic gear trains to predict the motions of the planets. Accurate predictions of the movement of the Sun, Moon, and the five planets, Mercury, Venus, Mars, Jupiter, and Saturn, across the sky assumed that each followed a trajectory traced by a point on the planet gear of an epicyclic
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The method of motion of a planetary gear structure is different from traditional parallel gears. Traditional gears rely on a small number of contact points between two gears to transfer the driving force. In this case, all the loading is concentrated on a few contacting surfaces, making the gears
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Planetary gear trains provide high power density in comparison to standard parallel axis gear trains. They provide a reduction in volume, multiple kinematic combinations, purely torsional reactions, and coaxial shafting. Disadvantages include high bearing loads, constant lubrication requirements,
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are easy to 3D print, it has become very popular to 3D print a moving herringbone planetary gear system for teaching children how gears work. An advantage of herringbone gears is that they don't fall out of the ring and don't need a mounting plate, allowing the moving parts to be clearly seen.
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In one arrangement, the planetary carrier (green in the diagram above) is held stationary, and the sun gear (yellow) is used as input. In that case, the planetary gears simply rotate about their own axes (i.e., spin) at a rate determined by the number of teeth in each gear. If the sun gear has
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A geared-down motor must turn farther and faster in order to produce the same output movement in the 3D printer which is advantageous if it is not outweighed by the slower movement speed. If the stepper motor has to turn farther then it also has to take more steps to move the printer a given
1618: 3741:— Torque of carrier. For all three, these are the torques applied to the mechanism (input torques). Output torques have the reverse sign of input torques. These torque ratios can be derived using the law of conservation of energy. Applied to a single stage this equation is expressed as: 4174: 4155: 2619: 5328:
distance; therefore, the geared-down stepper motor has a smaller minimum step-size than the same stepper motor without a gearbox. While down-gearing improves precision in unidirectional motion, it adds backlash to the system and so reduces its absolute positioning accuracy.
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The efficiency loss in a planetary gear train is typically about 3% per stage. This type of efficiency ensures that a high proportion (about 97%) of the energy being input is transmitted through the gearbox, rather than being wasted on mechanical losses inside the gearbox.
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The planetary gear train also provides stability due to an even distribution of mass and increased rotational stiffness. Torque applied radially onto the gears of a planetary gear train is transferred radially by the gear, without lateral pressure on the gear teeth.
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The fundamental formula of the planetary gear train with a rotating carrier is obtained by recognizing that this formula remains true if the angular velocities of the sun, planet and ring gears are computed relative to the carrier angular velocity. This becomes,
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mounted so that the center of one gear (the "planet") revolves around the center of the other (the "sun"). A carrier connects the centers of the two gears and rotates, to carry the planet gear(s) around the sun gear. The planet and sun gears mesh so that their
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In epicyclic gears, two speeds must be known, in order to determine the third speed. However, in a steady state condition, only one torque must be known, in order to determine the other two torques. The equations which determine torque are:
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for a few different reasons. Planetary gear boxes can provide a large gear ratio in a small, light-weight package. Some people install such gearboxes to get more accurate 3D prints by gearing-down the movement of their stepper motors.
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with stationary ring gear and rotating planet carrier as input. Planet gears are extended into cylindrical cutters, rotating around the pencil that is placed on the sun axis. The axes of planetary gears join at the pencil sharpening
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A convenient approach to determine the various speed ratios available in a planetary gear train begins by considering the speed ratio of the gear train when the carrier is held fixed. This is known as the fixed carrier train ratio.
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More planet and sun gear units can be placed in series in the same housing (where the output shaft of the first stage becomes the input shaft of the next stage) providing a larger (or smaller) gear ratio. This is the way most
4559:{\displaystyle {\frac {-\omega _{c}}{\omega _{r}-\omega _{c}}}=R,\quad {\mbox{or}}\quad {\frac {\omega _{r}}{\omega _{c}}}=1-{\frac {1}{R}},\quad {\mbox{so}}\quad {\frac {\omega _{r}}{\omega _{c}}}=1+{\frac {N_{s}}{N_{r}}}.} 3175:{\displaystyle \alpha _{\text{c}}={\frac {{\text{N}}_{\text{s}}}{{\text{N}}_{\text{s}}+{\text{N}}_{\text{r}}}}\alpha _{\text{s}}+{\frac {{\text{N}}_{\text{r}}}{{\text{N}}_{\text{s}}+{\text{N}}_{\text{r}}}}\alpha _{\text{r}}} 489:
of an epicyclic gearing system is somewhat non-intuitive, particularly because there are several ways in which an input rotation can be converted into an output rotation. The four basic components of the epicyclic gear are:
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The load in a planetary gear train is shared among multiple planets; therefore, torque capability is greatly increased. The more planets in the system, the greater the load ability and the higher the torque density.
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More than one member of a system can serve as an output. As an example, the input is connected to the ring gear, the sun gear is connected to the output and the planet carrier is connected to the output through a
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The ring gear may also be held fixed, with input provided to the planetary gear carrier; output rotation is then produced from the sun gear. This configuration will produce an increase in gear ratio, equal to
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Each of the speed ratios available to a simple planetary gear train can be obtained by using band brakes to hold and release the carrier, sun or ring gears as needed. This provides the basic structure for an
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is constructed from two identical coaxial epicyclic gear trains assembled with a single carrier such that their planet gears are engaged. This forms a planetary gear train with a fixed carrier train ratio
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of epicyclic gearing with 56-tooth ring gear locked (1), 24-tooth sun gear locked (2), carrier with 16-tooth planetary gears locked (3) and direct drive (4) – numbers denote relative angular speed
3029:{\displaystyle \alpha _{\text{r}}={\frac {{\text{N}}_{\text{s}}+{\text{N}}_{\text{r}}}{{\text{N}}_{\text{r}}}}\alpha _{\text{c}}-{\frac {{\text{N}}_{\text{s}}}{{\text{N}}_{\text{r}}}}\alpha _{\text{s}}} 2900:{\displaystyle \alpha _{\text{s}}={\frac {{\text{N}}_{\text{s}}+{\text{N}}_{\text{r}}}{{\text{N}}_{\text{s}}}}\alpha _{\text{c}}-{\frac {{\text{N}}_{\text{r}}}{{\text{N}}_{\text{s}}}}\alpha _{\text{r}}} 1667: 4987: 2679: 5233:
planetary carrier achieves the goal of speed reduction. A higher reduction ratio can be achieved by doubling the multiple staged gears and planetary gears which can operate within the same ring gear.
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work. In some cases multiple stages may even share the same ring gear which can be extended down the length of the transmission, or even be a structural part of the casing of smaller gearboxes.
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In the case of a simple planetary gear train formed by a carrier supporting a planet gear engaged with a sun and ring gear, the fixed carrier train ratio is computed as the speed ratio of the
2394: 4925: 1710:, receiving power from the system. The ratio of input rotation to output rotation is dependent upon the number of teeth in each of the gears, and upon which component is held stationary. 5964: 5387: 2692:, the sun is usually stationary, being keyed to the axle or even machined directly onto it. The planetary gear carrier is used as input. In this case the gear ratio is simply given by 412: 1500:{\displaystyle \omega _{\text{c}}={\frac {N_{\text{s}}}{\,N_{\text{s}}+N_{\text{r}}\,}}\,\omega _{\text{s}}+{\frac {N_{\text{r}}}{\,N_{\text{s}}+N_{\text{r}}\,}}\,\omega _{\text{r}}} 1700: 608:
The overall gear ratio of a simple planetary gearset can be calculated using the following two equations, representing the sun-planet and planet-ring interactions respectively:
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turns for each turn of the planetary gears. For instance, if the ring gear has 64 teeth, and the planets 16 teeth, one clockwise turn of a planet gear results in
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contain planet gears spaced 0°, 50°, 120°, and 230°, one is to calculate as if there are actually 36 planetary gears (10° equiangular), rather than the four real ones.
1233:{\displaystyle \omega _{\text{s}}={\frac {\,N_{\text{s}}+N_{\text{r}}\,}{N_{\text{s}}}}\,\omega _{\text{c}}-{\frac {\,N_{\text{r}}\,}{N_{\text{s}}}}\omega _{\text{r}}} 1781: 4588:
A spur gear differential constructed by engaging the planet gears of two co-axial epicyclic gear trains. The casing is the carrier for this planetary gear train.
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These relationships can be used to analyze any epicyclic system, including those, such as hybrid vehicle transmissions, where two of the components are used as
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An epicyclic gear train can be assembled so the planet gear rolls on the inside of the pitch circle of an outer gear ring, or ring gear, sometimes called an
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Split ring, compound planet, epicyclic gears of a car rear-view mirror positioner. This has a ratio from input sun gear to output black ring gear of −5/352.
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Animation of a printable gear set. Legend: driving shaft and sun gear (green), ring gear (dark gray), planet gears (blue), driven shaft and carrier (red).
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Rotation of the planet gears can in turn drive the ring gear (not depicted in diagram), at a speed corresponding to the gear ratios: If the ring gear has
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In this example, the carrier (green) is held stationary while the sun gear (yellow) is used as input. Analysis assumes a common gear design modulus. The
189:, circa 80 BCE, had gearing which was able to closely match the Moon's elliptical path through the heavens, and even to correct for the nine-year 5142:"Compound planetary gear" is a general concept and it refers to any planetary gears involving one or more of the following three types of structures: 3748: 2499:
If the ring gear is held stationary and the sun gear is used as the input, the planet carrier will be the output. The gear ratio in this case will be
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The red marks show the relative displacement of the sun gear and carrier, when the sun gear is rotated 180° clockwise and the ring gear is held fixed.
4805: 4610: 1613:{\displaystyle -{\frac {\,N_{\text{r}}\,}{N_{\text{s}}}}={\frac {\,\omega _{\text{s}}-\omega _{\text{c}}\,}{\omega _{\text{r}}-\omega _{\text{c}}}}} 5890: 3949: 3859: 255:, a vertically revolving bookstand containing epicyclic gearing with two levels of planetary gears to maintain proper orientation of the books. 5371: 2695: 4771:
Thus, the angular velocity of the carrier of a spur gear differential is the average of the angular velocities of the sun and ring gears.
4699: 310: 5972: 5461: 4150:{\displaystyle {\frac {\omega _{s}}{\omega _{r}}}=R,\quad {\mbox{so}}\quad {\frac {\omega _{s}}{\omega _{r}}}=-{\frac {N_{r}}{N_{s}}}.} 3577: 3429: 3346: 3263: 2614:{\displaystyle \,1/\left(1+{\tfrac {\,N_{\text{r}}\,}{N_{\text{s}}}}\right)={\tfrac {N_{\text{s}}}{\,N_{\text{s}}+N_{\text{r}}\,}}\;,} 2338: 2230: 1716: 2285: 2145: 2013: 1885: 151: 4996: 5063: 4029:
This formula provides a simple way to determine the speed ratios for the simple planetary gear train under different conditions:
1626: 1107:{\displaystyle N_{\text{s}}\,\omega _{\text{s}}+N_{\text{r}}\,\omega _{\text{r}}=(N_{\text{s}}+N_{\text{r}})\,\omega _{\text{c}}} 70:. By choosing to hold one component or another—the planetary carrier, the ring gear, or the sun gear—stationary, three different 4935: 2624: 3512: 3198: 175:
Around 500 BCE, the Greeks invented the idea of epicycles, of circles travelling on the circular orbits. With this theory
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This planetary gear train consists of a sun gear (yellow), planet gears (blue) and carrier (green) inside a ring gear (red)
5716: 6434: 6164: 5423: 5272: 2490:{\displaystyle \;1+{\tfrac {\,N_{\text{r}}\,}{N_{\text{s}}}}={\tfrac {\,N_{\text{s}}+N_{\text{r}}\,}{N_{\text{s}}}}~.} 5764: 5609: 5582: 5298: 5280: 6444: 6144: 5686: 4593: 137: 121:, which itself may rotate relative to the sun gear. Epicyclic gearing systems also incorporate the use of an outer 5876: 4879: 6003: 5138:
with the smaller planet series meshing with the sun wheel and the larger planet series meshing with the ring gear
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This is the lowest gear ratio attainable with an epicyclic gear train. This type of gearing is sometimes used in
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roll without slip. If the sun gear is held fixed, then a point on the pitch circle of the planet gear traces an
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of that path. (The Greeks interpreted the motion they saw, not as elliptical, but rather as epicyclic motion.)
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Miller, John M. (May 2006). "Hybrid electric vehicle propulsion system architectures of the e-CVT type".
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In the cases where gears are accelerating, or to account for friction, these equations must be modified.
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complete a single revolution, which in turn made the rotating ring gear rotate by a single tooth like a
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From the above formulae, we can also derive the accelerations of the sun, ring and carrier, which are:
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In many epicyclic gearing systems, one of these three basic components is held stationary (hence set
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P. A. Simionescu (1998-09-01). "A Unified Approach to the Assembly Condition of Epicyclic Gears".
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For instance, if the sun gear has 24 teeth, and each planet has 16 teeth, then the ratio is
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Alternatively, in the special case where the number of teeth on each gear meets the relationship
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as the ring gear when the planet carrier is the stationary. The fundamental equation becomes:
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In order that the planet gear teeth mesh properly with both the sun and ring gears, assuming
226: 214: 199: 186: 5969: 1869:{\displaystyle n\,\omega _{\text{s}}+(2+n)\,\omega _{\text{r}}-2(1+n)\,\omega _{\text{c}}=0} 6514: 6449: 6207: 5815: 5641: 910:{\displaystyle \omega _{\text{r}},\omega _{\text{s}},\omega _{\text{p}},\omega _{\text{c}}} 5788: 550:(blue) turn in a ratio determined by the number of teeth in each gear. Here, the ratio is 243:, an English abbot of St. Albans monastery, later described epicyclic gearing for an 8: 6539: 6519: 6304: 6051: 6046: 5996: 5819: 5645: 6685: 6590: 6275: 5831: 5657: 5146:(there are at least two or more planets in mesh with each other in each planet train), 513:(s): Usually two to four peripheral gears, all of the same size, that mesh between the 456: 244: 234: 5789:"How to derive and calculate epicyclic gear ratio equations in planetary gear systems" 5692:(Report). NASA Reference Publication. Vol. 1152. AVSCOM Technical Report 84-C-15. 185:
in 148 CE was able to approximate planetary paths observed crossing the sky. The
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the rate of the sun gear, in the opposite direction. An outer ring gear is not shown.
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gear, thus providing a reversal in direction compared to standard epicyclic gearing.
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One popular use of 3D printed planetary gear systems is as toys for children. Since
66:. Such an assembly of a planet engaging both a sun gear and a ring gear is called a 26: 6554: 6361: 6102: 5858: 5835: 5823: 5649: 5476: 5332: 5208: 5192: 5132: 918: 259: 248: 210: 176: 16:
Two gears mounted so the center of one gear revolves around the center of the other
6574: 6504: 6159: 6056: 6036: 5976: 5891:"52514 Caterpillar Tractor D8 Bulldozer Powershift Transmission Promotional Film" 5429: 5179: 71: 43: 5949: 5944: 5936:, movies and photos of hundreds of working mechanical-systems models at Cornell. 5150:(there exists a shaft connection between two planets in each planet train), and 3853:
formed by the sun, planet and ring gears on the fixed carrier. This is given by
3827:{\displaystyle \tau _{r}\omega _{r}+\tau _{c}\omega _{c}+\tau _{s}\omega _{s}=0} 6744: 6675: 6489: 6484: 6375: 6371: 6169: 5989: 5487: 5450: 2766: 5933: 5774: 5726: 4866:{\displaystyle (R-1)\omega _{\text{c}}=R\omega _{\text{r}}-\omega _{\text{s}}} 4683:{\displaystyle {\frac {\omega _{s}-\omega _{c}}{\omega _{r}-\omega _{c}}}=-1,} 6733: 6718: 6657: 6642: 6622: 6549: 6386: 6356: 6149: 6118: 5954: 5827: 5705:
Revolving Architecture: A history of buildings that rotate, swivel, and pivot
5653: 5203: 4019:{\displaystyle R={\frac {\omega _{s}-\omega _{c}}{\omega _{r}-\omega _{c}}}.} 3929:{\displaystyle R={\frac {\omega _{s}}{\omega _{r}}}=-{\frac {N_{r}}{N_{s}}}.} 1702:
for whichever gear is stationary); one of the two remaining components is an
538:: An outer ring with inward-facing teeth that mesh with the planetary gear(s) 6627: 6564: 6534: 6529: 6123: 5439: 5311: 5170: 4604:
In this case, the fundamental formula for the planetary gear train yields,
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So, with the planetary carrier locked, one turn of the sun gear results in
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clockwise turns of the ring gear. Extending this case from the one above:
229:, circa 80 BCE, to adjust the displayed position of the Moon for the 6708: 6632: 6605: 6600: 6464: 6454: 6270: 6230: 5393:
One of three sets of three gears inside the planet carrier of a Ford FMX
5320: 219: 2751:{\displaystyle {\tfrac {\,N_{\text{s}}+N_{\text{r}}\,}{N_{\text{r}}}}~.} 144:(see below). Further, the sun, planet carrier and ring axes are usually 82: 6690: 6652: 6494: 6327: 6250: 6197: 6154: 6087: 6082: 6031: 5918:
Gears and Their Vibration: A Basic Approach to Understanding Gear Noise
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and construction equipment to provide high torque to the drive wheels.
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equally spaced planet gears, the following equation must be satisfied:
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The axes of all gears are usually parallel, but for special cases like
56: 5939: 5862: 5173:, a special variation of epicyclic gearing was developed for portable 480: 6647: 6637: 6559: 6524: 6280: 6260: 6255: 6077: 6026: 5684: 5493: 252: 155: 5250: 4761:{\displaystyle \omega _{c}={\frac {1}{2}}(\omega _{s}+\omega _{r}).} 6439: 6222: 6212: 6202: 6097: 5455: 5362: 5135: 2689: 2682: 362:{\displaystyle {\frac {N_{\text{s}}+N_{\text{r}}}{n_{\text{p}}}}=A} 205: 181: 5445: 507:
gear(s) symmetrically and separated, all meshed with the sun gear
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not have the internal gear mate that is typical of a ring gear.
3649:{\displaystyle \tau _{s}=-\tau _{c}{\frac {N_{s}}{N_{r}+N_{s}}}} 3501:{\displaystyle \tau _{c}=-\tau _{s}{\frac {N_{r}+N_{s}}{N_{s}}}} 3418:{\displaystyle \tau _{c}=-\tau _{r}{\frac {N_{r}+N_{s}}{N_{r}}}} 3335:{\displaystyle \tau _{r}=-\tau _{c}{\frac {N_{r}}{N_{r}+N_{s}}}} 1706:, providing power to the system, while the last component is an 262:
designed and constructed the first mill with epicycloidal teeth
6610: 6424: 6192: 5959: 5604:(2nd ed.). Oxford, UK: Butterworth-Heinemann. p. 58. 106: 4774:
In discussing the spur gear differential, the use of the term
3185: 2773: 2380:{\displaystyle \;-{\tfrac {\,N_{\text{s}}\,}{N_{\text{r}}}}\;} 2272:{\displaystyle \,-{\tfrac {\,N_{\text{s}}\,}{N_{\text{p}}}}\,} 1768:{\displaystyle \,N_{\text{r}}=N_{\text{s}}+2\,N_{\text{p}}\;,} 117:. Typically, the planet gears are mounted on a movable arm or 6595: 6499: 6296: 5746: 5577:(4th ed.). Cheltenham, UK: Nelson Thornes. p. 244. 5174: 2324:{\displaystyle \,{\tfrac {\,N_{\text{p}}\,}{N_{\text{r}}}}\,} 2184:{\displaystyle \,{\tfrac {\,N_{\text{p}}\,}{N_{\text{r}}}}\,} 2057:{\displaystyle -{\tfrac {\,N_{\text{s}}\,}{N_{\text{p}}}}\;.} 1929:{\displaystyle n={\tfrac {\,N_{\text{s}}\,}{N_{\text{p}}}}\;} 247:
in the 14th century. In 1588, Italian military engineer
5049:{\displaystyle \omega _{\text{r}}=\omega _{\text{c}}(R-1)/R} 2761: 6617: 6012: 5111:{\displaystyle \omega _{\text{s}}=-\omega _{\text{c}}(R-1)} 4782: 1662:{\displaystyle \omega _{\text{r}}\neq \omega _{\text{c}}~.} 98: 47: 4982:{\displaystyle \omega _{\text{r}}=\omega _{\text{s}}(1/R)} 2674:{\displaystyle \;N_{\text{s}}:N_{\text{s}}+N_{\text{r}}~.} 140:, they can be placed at an angle, introducing elements of 6338: 3566:{\displaystyle \tau _{s}=\tau _{r}{\frac {N_{s}}{N_{r}}}} 3252:{\displaystyle \tau _{r}=\tau _{s}{\frac {N_{r}}{N_{s}}}} 5981: 5707:. New York, NY: Princeton Architectural Press. p.  5515: 5513: 5511: 4489: 4434: 4281: 4233: 4083: 3939:
In this calculation the planet gear is an idler gear.
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The number of teeth in the planet gear is irrelevant.
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J. J. Uicker, G. R. Pennock and J. E. Shigley, 2003,
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Kinematic Models for Design Digital Library (KMODDL)
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turns of each of the planet gear(s) about its axis.
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Science and Technology in the Industrial Revolution
5508: 5496:- a wheel that incorporates a planetary gear system 481:
Gear speed ratios of conventional epicyclic gearing
5748: 5740: 5685:Coy, J.J.; Townsend, D.P.; Zaretsky, E.V. (1985). 5618: 5110: 5048: 4981: 4919: 4865: 4760: 4682: 4558: 4350: 4149: 4018: 3928: 3826: 3733: 3706: 3679: 3648: 3565: 3500: 3417: 3334: 3251: 3174: 3028: 2899: 2750: 2673: 2613: 2489: 2379: 2323: 2271: 2183: 2134: 2056: 2002: 1973: 1928: 1868: 1767: 1694: 1661: 1612: 1499: 1359: 1232: 1106: 982: 909: 837: 465: 451:is the number of planet gears in the assembly and 443: 406: 361: 296: 5597: 1775:the equation can be re-written as the following: 6731: 5848: 5920:. Marcel Dekker, New York and MacMillan, London 5805: 5571:"Planetary gearing and unidirectional clutches" 5154:(the system contains two or more planet sets). 5531: 5529: 19:For the ring gear used in starter motors, see 6312: 5997: 5955:The "Interactive Planetary Gearset tutorial" 4920:{\displaystyle R=-N_{\text{r}}/N_{\text{s}}} 3840: 5702: 5537:Kinematics and Dynamics of Planar Machinery 5526: 5279:. Unsourced material may be challenged and 5122: 3186:Torque ratios of standard epicyclic gearing 2774:Accelerations of standard epicyclic gearing 101:system consisting of one or more outer, or 6319: 6305: 6004: 5990: 5970:Short Cuts for Analyzing Planetary Gearing 5905:Gear Drive Systems: Design and Application 5462:NuVinci continuously variable transmission 5420:– ancient mechanical astronomical computer 2628: 2607: 2398: 2376: 2342: 2050: 1925: 1761: 5299:Learn how and when to remove this message 4579: 2727: 2703: 2602: 2578: 2541: 2530: 2506: 2466: 2442: 2420: 2409: 2361: 2350: 2320: 2305: 2294: 2289: 2268: 2253: 2242: 2234: 2180: 2165: 2154: 2149: 2131: 2120: 2035: 2024: 1999: 1988: 1970: 1959: 1910: 1899: 1849: 1817: 1788: 1750: 1720: 1581: 1557: 1537: 1526: 1486: 1482: 1458: 1431: 1427: 1403: 1346: 1332: 1321: 1304: 1290: 1266: 1206: 1195: 1178: 1164: 1140: 1093: 1050: 1026: 810: 763: 739: 704: 698: 656: 632: 588:; meaning that each planet gear turns at 407:{\displaystyle N_{\text{s}},N_{\text{r}}} 5747:Musson, A.E.; Robinson, Eric H. (1969). 5627:"The Antikythera Mechanism reconsidered" 5575:Fundamentals of Motor Vehicle Technology 5310: 5217:inaccessibility, and design complexity. 5202: 5126: 4786: 4783:Gear ratio of reversed epicyclic gearing 4583: 2760: 1006:from which we can derive the following: 541: 150: 81: 25: 5568: 5442:– had a 2 speed planetary transmission. 5319:Planetary gears have become popular in 2106:turn of the sun gear produces 1.5  6732: 5808:IEEE Transactions on Power Electronics 5624: 1695:{\displaystyle \omega _{\text{...}}=0} 6300: 5985: 5680: 5678: 2282:One turn of a planet gear results in 5940:"Epicyclic gearing animation in SVG" 5598:Harrison, H.; Nettleton, T. (1994). 5277:adding citations to reliable sources 5244: 2227:One turn of the sun gear results in 2142:teeth, then the ring will rotate by 218:gear train. This curve is called an 196:In the 2nd century AD treatise 5601:Principles of Engineering Mechanics 13: 6435:Continuously variable transmission 6165:Continuously variable transmission 5675: 5523:Oxford University Press, New York. 5521:Theory of Machines and Mechanisms, 5424:Continuously variable transmission 5185: 2769:AM bicycle hub (ring gear removed) 2010:teeth, then the ratio is equal to 258:French mathematician and engineer 225:Epicyclic gearing was used in the 14: 6756: 5927: 5634:Interdisciplinary Science Reviews 4162:2. The ring gear is held fixed, ω 273:Requirements for non-interference 6714: 6713: 6703: 5945:"Animation of Epicyclic gearing" 5386: 5370: 5361: 5349: 5249: 4363:3. The sun gear is held fixed, ω 2135:{\displaystyle \,N_{\text{r}}\,} 2003:{\displaystyle \,N_{\text{p}}\,} 1981:teeth, and each planet gear has 1974:{\displaystyle \,N_{\text{s}}\,} 1936:is the sun-to-planet gear ratio. 5910: 5897: 5883: 5869: 5781: 4495: 4487: 4440: 4432: 4287: 4279: 4239: 4231: 4089: 4081: 4032:1. The carrier is held fixed, ω 990:are the number of teeth of the 414:are the number of teeth of the 160:Le diverse et artifiose machine 6326: 5696: 5591: 5562: 5542: 5479:– 14-ratio bicycle hub gearbox 5379:Pratt & Whitney Canada PT6 5240: 5105: 5093: 5035: 5023: 4976: 4962: 4821: 4809: 4752: 4726: 1846: 1834: 1814: 1802: 1090: 1064: 1: 6470:Automated manual transmission 6042:Epicyclic (planetary) gearing 5501: 5198: 5136:internally geared bicycle hub 5131:Stepped planet series of the 5118:when the ring gear is locked. 2621:which may also be written as 263: 5851:Journal of Mechanical Design 5467:Ravigneaux planetary gearset 3687:— Torque of ring (annulus), 1948:relative to the two inputs. 444:{\displaystyle n_{\text{p}}} 297:{\displaystyle n_{\text{p}}} 109:, revolving about a central 7: 6545:Semi-automatic transmission 5703:Randl, Chad (15 May 2008). 5405: 4989:when the carrier is locked, 233:, and even for its orbital 77: 46:assembly consisting of two 10: 6761: 6382:Internal combustion engine 5472:Lepelletier gear mechanism 5339: 170: 158:, from Agostino Ramelli's 18: 6699: 6681:Hybrid vehicle drivetrain 6668: 6583: 6570:Transmission control unit 6510:Limited-slip differential 6475:Electrorheological clutch 6400: 6347: 6334: 6286:Spur gear corrected tooth 6243: 6221: 6185: 6178: 6132: 6111: 6070: 6019: 6011: 5907:. Marcel Dekker, New York 5483:Simpson planetary gearset 3841:Fixed carrier train ratio 3734:{\displaystyle \tau _{c}} 3707:{\displaystyle \tau _{s}} 3680:{\displaystyle \tau _{r}} 1944:with the third providing 6460:Dual-clutch transmission 5950:The "Power Split Device" 5828:10.1109/TPEL.2006.872372 5654:10.1179/030801807X163670 5569:Hillier, V.A.W. (2001). 5556:University of California 5123:Compound planetary gears 2387:turns of the ring gear. 231:ellipticity of its orbit 6430:Constant-velocity joint 5164:automatic transmissions 5056:when the sun is locked, 6410:Automatic transmission 5316: 5213: 5152:multi-stage structures 5139: 5112: 5050: 4983: 4921: 4867: 4795: 4762: 4684: 4594:spur gear differential 4589: 4580:Spur gear differential 4574:automatic transmission 4560: 4352: 4151: 4020: 3930: 3828: 3735: 3708: 3681: 3650: 3567: 3502: 3419: 3336: 3253: 3176: 3030: 2901: 2770: 2765:Compound planets of a 2752: 2675: 2615: 2491: 2381: 2331:turns of the ring gear 2325: 2273: 2185: 2136: 2102:; this means that one 2058: 2004: 1975: 1930: 1870: 1769: 1696: 1663: 1614: 1501: 1361: 1234: 1108: 984: 911: 839: 605: 467: 445: 408: 363: 298: 241:Richard of Wallingford 215:deferent and epicycles 163: 87: 31: 5903:Lynwander, P., 1983, 5625:Wright, M.T. (2007). 5418:Antikythera mechanism 5413:Hypocycloidal gearing 5314: 5206: 5130: 5113: 5051: 4984: 4922: 4868: 4790: 4763: 4685: 4587: 4561: 4353: 4152: 4021: 3931: 3829: 3736: 3709: 3682: 3651: 3568: 3503: 3420: 3337: 3254: 3177: 3031: 2902: 2764: 2753: 2676: 2616: 2492: 2382: 2326: 2274: 2186: 2137: 2059: 2005: 1976: 1931: 1871: 1770: 1697: 1664: 1615: 1502: 1362: 1235: 1109: 985: 912: 840: 545: 468: 446: 409: 364: 299: 227:Antikythera Mechanism 200:Mathematical Syntaxis 187:Antikythera Mechanism 154: 85: 29: 6515:Locking differential 6450:Direct-shift gearbox 6208:Shaft-driven bicycle 5916:Smith, J. D., 1983, 5558:. 1913. p. 979. 5551:Machinery, Volume 19 5458:, for bicycles, etc. 5273:improve this section 5064: 4997: 4936: 4880: 4806: 4700: 4611: 4376: 4175: 4045: 3950: 3860: 3749: 3718: 3691: 3664: 3578: 3513: 3430: 3347: 3264: 3199: 3043: 2914: 2785: 2696: 2625: 2503: 2395: 2339: 2286: 2279:turns of the planets 2231: 2146: 2117: 2014: 1985: 1956: 1886: 1782: 1717: 1673: 1627: 1517: 1374: 1247: 1121: 1013: 941: 855: 615: 503:: Holds one or more 457: 428: 378: 311: 281: 68:planetary gear train 36:epicyclic gear train 6740:Epicyclical gearing 6540:Preselector gearbox 6520:Manual transmission 6047:Sun and planet gear 5820:2006ITPE...21..756M 5646:2007ISRv...32...27W 5381:gas turbine engine. 5377:Reduction gears on 5207:The mechanism of a 422:, respectively and 6686:Electric generator 6591:Wheel hub assembly 6276:Gear manufacturing 6112:Geartooth profiles 5975:2021-02-25 at the 5877:"Archimedes Drive" 5317: 5214: 5140: 5108: 5046: 4979: 4929:which results in: 4917: 4863: 4796: 4758: 4680: 4590: 4556: 4493: 4438: 4348: 4285: 4237: 4147: 4087: 4016: 3926: 3824: 3731: 3704: 3677: 3646: 3563: 3498: 3415: 3332: 3249: 3172: 3026: 2897: 2771: 2748: 2740: 2671: 2611: 2605: 2554: 2487: 2479: 2433: 2377: 2374: 2321: 2318: 2269: 2266: 2181: 2178: 2132: 2054: 2048: 2000: 1971: 1926: 1923: 1866: 1765: 1692: 1659: 1610: 1497: 1357: 1230: 1104: 980: 937:respectively, and 919:angular velocities 907: 835: 833: 606: 497:: The central gear 473:is a whole number 463: 441: 404: 359: 294: 245:astronomical clock 235:apsidal precession 164: 88: 32: 6727: 6726: 6480:Epicyclic gearing 6349:Automotive engine 6294: 6293: 6239: 6238: 6062:Non-circular gear 6027:Spur gear systems 5965:Planetary Gearbox 5893:. 10 August 2022. 5863:10.1115/1.2829172 5333:herringbone gears 5309: 5308: 5301: 5090: 5074: 5020: 5007: 4959: 4946: 4914: 4899: 4860: 4847: 4831: 4724: 4666: 4601: = −1. 4551: 4518: 4492: 4482: 4463: 4437: 4421: 4343: 4310: 4284: 4262: 4236: 4220: 4142: 4112: 4086: 4070: 4011: 3921: 3891: 3714:— Torque of sun, 3644: 3561: 3496: 3413: 3330: 3247: 3169: 3160: 3156: 3151: 3141: 3136: 3128: 3123: 3111: 3102: 3098: 3093: 3083: 3078: 3070: 3065: 3053: 3023: 3014: 3011: 3006: 2999: 2994: 2982: 2973: 2970: 2965: 2957: 2952: 2942: 2937: 2924: 2894: 2885: 2882: 2877: 2870: 2865: 2853: 2844: 2841: 2836: 2828: 2823: 2813: 2808: 2795: 2744: 2739: 2736: 2724: 2711: 2667: 2662: 2649: 2636: 2604: 2599: 2586: 2574: 2553: 2550: 2538: 2483: 2478: 2475: 2463: 2450: 2432: 2429: 2417: 2373: 2370: 2358: 2317: 2314: 2302: 2265: 2262: 2250: 2177: 2174: 2162: 2128: 2047: 2044: 2032: 1996: 1967: 1922: 1919: 1907: 1857: 1825: 1796: 1758: 1741: 1728: 1683: 1655: 1650: 1637: 1608: 1604: 1591: 1578: 1565: 1549: 1546: 1534: 1494: 1484: 1479: 1466: 1454: 1439: 1429: 1424: 1411: 1399: 1384: 1354: 1344: 1341: 1329: 1312: 1302: 1299: 1287: 1274: 1257: 1227: 1218: 1215: 1203: 1186: 1176: 1173: 1161: 1148: 1131: 1101: 1087: 1074: 1058: 1047: 1034: 1023: 977: 964: 951: 904: 891: 878: 865: 818: 802: 789: 771: 760: 747: 736: 712: 695: 682: 664: 653: 640: 629: 466:{\displaystyle A} 438: 401: 388: 351: 348: 337: 324: 291: 134:pencil sharpeners 95:planetary gearing 91:Epicyclic gearing 74:can be realized. 40:planetary gearset 38:(also known as a 21:Starter ring gear 6752: 6717: 6716: 6707: 6584:Wheels and tires 6555:Torque converter 6321: 6314: 6307: 6298: 6297: 6183: 6182: 6006: 5999: 5992: 5983: 5982: 5921: 5914: 5908: 5901: 5895: 5894: 5887: 5881: 5880: 5873: 5867: 5866: 5846: 5840: 5839: 5803: 5797: 5796: 5785: 5779: 5778: 5754: 5744: 5738: 5730: 5700: 5694: 5693: 5691: 5682: 5673: 5672: 5670: 5668: 5631: 5622: 5616: 5615: 5595: 5589: 5588: 5566: 5560: 5559: 5546: 5540: 5539:, Prentice Hall. 5533: 5524: 5517: 5477:Rohloff Speedhub 5390: 5374: 5365: 5353: 5304: 5297: 5293: 5290: 5284: 5253: 5245: 5209:pencil sharpener 5193:torque converter 5133:Rohloff Speedhub 5117: 5115: 5114: 5109: 5092: 5091: 5088: 5076: 5075: 5072: 5055: 5053: 5052: 5047: 5042: 5022: 5021: 5018: 5009: 5008: 5005: 4988: 4986: 4985: 4980: 4972: 4961: 4960: 4957: 4948: 4947: 4944: 4926: 4924: 4923: 4918: 4916: 4915: 4912: 4906: 4901: 4900: 4897: 4872: 4870: 4869: 4864: 4862: 4861: 4858: 4849: 4848: 4845: 4833: 4832: 4829: 4767: 4765: 4764: 4759: 4751: 4750: 4738: 4737: 4725: 4717: 4712: 4711: 4689: 4687: 4686: 4681: 4667: 4665: 4664: 4663: 4651: 4650: 4640: 4639: 4638: 4626: 4625: 4615: 4565: 4563: 4562: 4557: 4552: 4550: 4549: 4540: 4539: 4530: 4519: 4517: 4516: 4507: 4506: 4497: 4494: 4490: 4483: 4475: 4464: 4462: 4461: 4452: 4451: 4442: 4439: 4435: 4422: 4420: 4419: 4418: 4406: 4405: 4395: 4394: 4393: 4380: 4357: 4355: 4354: 4349: 4344: 4342: 4341: 4332: 4331: 4322: 4311: 4309: 4308: 4299: 4298: 4289: 4286: 4282: 4263: 4261: 4260: 4251: 4250: 4241: 4238: 4234: 4221: 4219: 4218: 4217: 4204: 4203: 4202: 4190: 4189: 4179: 4156: 4154: 4153: 4148: 4143: 4141: 4140: 4131: 4130: 4121: 4113: 4111: 4110: 4101: 4100: 4091: 4088: 4084: 4071: 4069: 4068: 4059: 4058: 4049: 4025: 4023: 4022: 4017: 4012: 4010: 4009: 4008: 3996: 3995: 3985: 3984: 3983: 3971: 3970: 3960: 3935: 3933: 3932: 3927: 3922: 3920: 3919: 3910: 3909: 3900: 3892: 3890: 3889: 3880: 3879: 3870: 3833: 3831: 3830: 3825: 3817: 3816: 3807: 3806: 3794: 3793: 3784: 3783: 3771: 3770: 3761: 3760: 3740: 3738: 3737: 3732: 3730: 3729: 3713: 3711: 3710: 3705: 3703: 3702: 3686: 3684: 3683: 3678: 3676: 3675: 3655: 3653: 3652: 3647: 3645: 3643: 3642: 3641: 3629: 3628: 3618: 3617: 3608: 3606: 3605: 3590: 3589: 3572: 3570: 3569: 3564: 3562: 3560: 3559: 3550: 3549: 3540: 3538: 3537: 3525: 3524: 3507: 3505: 3504: 3499: 3497: 3495: 3494: 3485: 3484: 3483: 3471: 3470: 3460: 3458: 3457: 3442: 3441: 3424: 3422: 3421: 3416: 3414: 3412: 3411: 3402: 3401: 3400: 3388: 3387: 3377: 3375: 3374: 3359: 3358: 3341: 3339: 3338: 3333: 3331: 3329: 3328: 3327: 3315: 3314: 3304: 3303: 3294: 3292: 3291: 3276: 3275: 3258: 3256: 3255: 3250: 3248: 3246: 3245: 3236: 3235: 3226: 3224: 3223: 3211: 3210: 3181: 3179: 3178: 3173: 3171: 3170: 3167: 3161: 3159: 3158: 3157: 3154: 3152: 3149: 3143: 3142: 3139: 3137: 3134: 3130: 3129: 3126: 3124: 3121: 3118: 3113: 3112: 3109: 3103: 3101: 3100: 3099: 3096: 3094: 3091: 3085: 3084: 3081: 3079: 3076: 3072: 3071: 3068: 3066: 3063: 3060: 3055: 3054: 3051: 3035: 3033: 3032: 3027: 3025: 3024: 3021: 3015: 3013: 3012: 3009: 3007: 3004: 3001: 3000: 2997: 2995: 2992: 2989: 2984: 2983: 2980: 2974: 2972: 2971: 2968: 2966: 2963: 2960: 2959: 2958: 2955: 2953: 2950: 2944: 2943: 2940: 2938: 2935: 2931: 2926: 2925: 2922: 2906: 2904: 2903: 2898: 2896: 2895: 2892: 2886: 2884: 2883: 2880: 2878: 2875: 2872: 2871: 2868: 2866: 2863: 2860: 2855: 2854: 2851: 2845: 2843: 2842: 2839: 2837: 2834: 2831: 2830: 2829: 2826: 2824: 2821: 2815: 2814: 2811: 2809: 2806: 2802: 2797: 2796: 2793: 2757: 2755: 2754: 2749: 2742: 2741: 2738: 2737: 2734: 2728: 2726: 2725: 2722: 2713: 2712: 2709: 2701: 2680: 2678: 2677: 2672: 2665: 2664: 2663: 2660: 2651: 2650: 2647: 2638: 2637: 2634: 2620: 2618: 2617: 2612: 2606: 2603: 2601: 2600: 2597: 2588: 2587: 2584: 2576: 2575: 2572: 2566: 2560: 2556: 2555: 2552: 2551: 2548: 2542: 2540: 2539: 2536: 2528: 2514: 2496: 2494: 2493: 2488: 2481: 2480: 2477: 2476: 2473: 2467: 2465: 2464: 2461: 2452: 2451: 2448: 2440: 2434: 2431: 2430: 2427: 2421: 2419: 2418: 2415: 2407: 2386: 2384: 2383: 2378: 2375: 2372: 2371: 2368: 2362: 2360: 2359: 2356: 2348: 2330: 2328: 2327: 2322: 2319: 2316: 2315: 2312: 2306: 2304: 2303: 2300: 2292: 2278: 2276: 2275: 2270: 2267: 2264: 2263: 2260: 2254: 2252: 2251: 2248: 2240: 2222: 2220: 2219: 2216: 2213: 2206: 2204: 2203: 2200: 2197: 2190: 2188: 2187: 2182: 2179: 2176: 2175: 2172: 2166: 2164: 2163: 2160: 2152: 2141: 2139: 2138: 2133: 2130: 2129: 2126: 2108:counterclockwise 2101: 2099: 2098: 2095: 2092: 2088: 2082: 2080: 2079: 2076: 2073: 2069: 2063: 2061: 2060: 2055: 2049: 2046: 2045: 2042: 2036: 2034: 2033: 2030: 2022: 2009: 2007: 2006: 2001: 1998: 1997: 1994: 1980: 1978: 1977: 1972: 1969: 1968: 1965: 1935: 1933: 1932: 1927: 1924: 1921: 1920: 1917: 1911: 1909: 1908: 1905: 1897: 1875: 1873: 1872: 1867: 1859: 1858: 1855: 1827: 1826: 1823: 1798: 1797: 1794: 1774: 1772: 1771: 1766: 1760: 1759: 1756: 1743: 1742: 1739: 1730: 1729: 1726: 1701: 1699: 1698: 1693: 1685: 1684: 1681: 1668: 1666: 1665: 1660: 1653: 1652: 1651: 1648: 1639: 1638: 1635: 1619: 1617: 1616: 1611: 1609: 1607: 1606: 1605: 1602: 1593: 1592: 1589: 1582: 1580: 1579: 1576: 1567: 1566: 1563: 1555: 1550: 1548: 1547: 1544: 1538: 1536: 1535: 1532: 1524: 1506: 1504: 1503: 1498: 1496: 1495: 1492: 1485: 1483: 1481: 1480: 1477: 1468: 1467: 1464: 1456: 1455: 1452: 1446: 1441: 1440: 1437: 1430: 1428: 1426: 1425: 1422: 1413: 1412: 1409: 1401: 1400: 1397: 1391: 1386: 1385: 1382: 1366: 1364: 1363: 1358: 1356: 1355: 1352: 1345: 1343: 1342: 1339: 1333: 1331: 1330: 1327: 1319: 1314: 1313: 1310: 1303: 1301: 1300: 1297: 1291: 1289: 1288: 1285: 1276: 1275: 1272: 1264: 1259: 1258: 1255: 1239: 1237: 1236: 1231: 1229: 1228: 1225: 1219: 1217: 1216: 1213: 1207: 1205: 1204: 1201: 1193: 1188: 1187: 1184: 1177: 1175: 1174: 1171: 1165: 1163: 1162: 1159: 1150: 1149: 1146: 1138: 1133: 1132: 1129: 1113: 1111: 1110: 1105: 1103: 1102: 1099: 1089: 1088: 1085: 1076: 1075: 1072: 1060: 1059: 1056: 1049: 1048: 1045: 1036: 1035: 1032: 1025: 1024: 1021: 989: 987: 986: 981: 979: 978: 975: 966: 965: 962: 953: 952: 949: 916: 914: 913: 908: 906: 905: 902: 893: 892: 889: 880: 879: 876: 867: 866: 863: 844: 842: 841: 836: 834: 820: 819: 816: 809: 805: 804: 803: 800: 791: 790: 787: 773: 772: 769: 762: 761: 758: 749: 748: 745: 738: 737: 734: 714: 713: 710: 703: 699: 697: 696: 693: 684: 683: 680: 666: 665: 662: 655: 654: 651: 642: 641: 638: 631: 630: 627: 603: 601: 600: 597: 594: 587: 585: 584: 581: 578: 574: 568: 566: 565: 562: 559: 555: 472: 470: 469: 464: 450: 448: 447: 442: 440: 439: 436: 413: 411: 410: 405: 403: 402: 399: 390: 389: 386: 368: 366: 365: 360: 352: 350: 349: 346: 340: 339: 338: 335: 326: 325: 322: 315: 303: 301: 300: 295: 293: 292: 289: 268: 265: 249:Agostino Ramelli 211:Claudius Ptolemy 177:Claudius Ptolemy 6760: 6759: 6755: 6754: 6753: 6751: 6750: 6749: 6730: 6729: 6728: 6723: 6695: 6664: 6579: 6575:Universal joint 6505:Hotchkiss drive 6396: 6343: 6330: 6325: 6295: 6290: 6235: 6217: 6174: 6160:Bicycle gearing 6128: 6107: 6066: 6057:Cycloidal drive 6037:Rack and pinion 6015: 6010: 5977:Wayback Machine 5930: 5925: 5924: 5915: 5911: 5902: 5898: 5889: 5888: 5884: 5875: 5874: 5870: 5847: 5843: 5804: 5800: 5787: 5786: 5782: 5767: 5745: 5741: 5719: 5718:978-156898681-4 5701: 5697: 5689: 5683: 5676: 5666: 5664: 5629: 5623: 5619: 5612: 5596: 5592: 5585: 5567: 5563: 5548: 5547: 5543: 5535:B. Paul, 1979, 5534: 5527: 5518: 5509: 5504: 5499: 5430:Cycloidal drive 5408: 5403: 5402: 5401: 5398: 5391: 5382: 5375: 5366: 5357: 5354: 5342: 5305: 5294: 5288: 5285: 5270: 5254: 5243: 5201: 5188: 5186:Power splitting 5180:cycloidal drive 5125: 5087: 5083: 5071: 5067: 5065: 5062: 5061: 5038: 5017: 5013: 5004: 5000: 4998: 4995: 4994: 4968: 4956: 4952: 4943: 4939: 4937: 4934: 4933: 4911: 4907: 4902: 4896: 4892: 4881: 4878: 4877: 4857: 4853: 4844: 4840: 4828: 4824: 4807: 4804: 4803: 4785: 4746: 4742: 4733: 4729: 4716: 4707: 4703: 4701: 4698: 4697: 4659: 4655: 4646: 4642: 4641: 4634: 4630: 4621: 4617: 4616: 4614: 4612: 4609: 4608: 4582: 4545: 4541: 4535: 4531: 4529: 4512: 4508: 4502: 4498: 4496: 4488: 4474: 4457: 4453: 4447: 4443: 4441: 4433: 4414: 4410: 4401: 4397: 4396: 4389: 4385: 4381: 4379: 4377: 4374: 4373: 4366: 4337: 4333: 4327: 4323: 4321: 4304: 4300: 4294: 4290: 4288: 4280: 4256: 4252: 4246: 4242: 4240: 4232: 4213: 4209: 4205: 4198: 4194: 4185: 4181: 4180: 4178: 4176: 4173: 4172: 4165: 4136: 4132: 4126: 4122: 4120: 4106: 4102: 4096: 4092: 4090: 4082: 4064: 4060: 4054: 4050: 4048: 4046: 4043: 4042: 4035: 4004: 4000: 3991: 3987: 3986: 3979: 3975: 3966: 3962: 3961: 3959: 3951: 3948: 3947: 3915: 3911: 3905: 3901: 3899: 3885: 3881: 3875: 3871: 3869: 3861: 3858: 3857: 3843: 3812: 3808: 3802: 3798: 3789: 3785: 3779: 3775: 3766: 3762: 3756: 3752: 3750: 3747: 3746: 3742: 3725: 3721: 3719: 3716: 3715: 3698: 3694: 3692: 3689: 3688: 3671: 3667: 3665: 3662: 3661: 3659: 3637: 3633: 3624: 3620: 3619: 3613: 3609: 3607: 3601: 3597: 3585: 3581: 3579: 3576: 3575: 3555: 3551: 3545: 3541: 3539: 3533: 3529: 3520: 3516: 3514: 3511: 3510: 3490: 3486: 3479: 3475: 3466: 3462: 3461: 3459: 3453: 3449: 3437: 3433: 3431: 3428: 3427: 3407: 3403: 3396: 3392: 3383: 3379: 3378: 3376: 3370: 3366: 3354: 3350: 3348: 3345: 3344: 3323: 3319: 3310: 3306: 3305: 3299: 3295: 3293: 3287: 3283: 3271: 3267: 3265: 3262: 3261: 3241: 3237: 3231: 3227: 3225: 3219: 3215: 3206: 3202: 3200: 3197: 3196: 3192: 3188: 3166: 3162: 3153: 3148: 3147: 3138: 3133: 3132: 3131: 3125: 3120: 3119: 3117: 3108: 3104: 3095: 3090: 3089: 3080: 3075: 3074: 3073: 3067: 3062: 3061: 3059: 3050: 3046: 3044: 3041: 3040: 3020: 3016: 3008: 3003: 3002: 2996: 2991: 2990: 2988: 2979: 2975: 2967: 2962: 2961: 2954: 2949: 2948: 2939: 2934: 2933: 2932: 2930: 2921: 2917: 2915: 2912: 2911: 2891: 2887: 2879: 2874: 2873: 2867: 2862: 2861: 2859: 2850: 2846: 2838: 2833: 2832: 2825: 2820: 2819: 2810: 2805: 2804: 2803: 2801: 2792: 2788: 2786: 2783: 2782: 2776: 2733: 2729: 2721: 2717: 2708: 2704: 2702: 2699: 2697: 2694: 2693: 2659: 2655: 2646: 2642: 2633: 2629: 2626: 2623: 2622: 2596: 2592: 2583: 2579: 2577: 2571: 2567: 2564: 2547: 2543: 2535: 2531: 2529: 2526: 2519: 2515: 2510: 2504: 2501: 2500: 2472: 2468: 2460: 2456: 2447: 2443: 2441: 2438: 2426: 2422: 2414: 2410: 2408: 2405: 2396: 2393: 2392: 2367: 2363: 2355: 2351: 2349: 2346: 2340: 2337: 2336: 2311: 2307: 2299: 2295: 2293: 2290: 2287: 2284: 2283: 2259: 2255: 2247: 2243: 2241: 2238: 2232: 2229: 2228: 2217: 2214: 2211: 2210: 2208: 2201: 2198: 2195: 2194: 2192: 2171: 2167: 2159: 2155: 2153: 2150: 2147: 2144: 2143: 2125: 2121: 2118: 2115: 2114: 2096: 2093: 2090: 2089: 2086: 2084: 2077: 2074: 2071: 2070: 2067: 2065: 2041: 2037: 2029: 2025: 2023: 2020: 2015: 2012: 2011: 1993: 1989: 1986: 1983: 1982: 1964: 1960: 1957: 1954: 1953: 1916: 1912: 1904: 1900: 1898: 1895: 1887: 1884: 1883: 1854: 1850: 1822: 1818: 1793: 1789: 1783: 1780: 1779: 1755: 1751: 1738: 1734: 1725: 1721: 1718: 1715: 1714: 1680: 1676: 1674: 1671: 1670: 1647: 1643: 1634: 1630: 1628: 1625: 1624: 1601: 1597: 1588: 1584: 1583: 1575: 1571: 1562: 1558: 1556: 1554: 1543: 1539: 1531: 1527: 1525: 1523: 1518: 1515: 1514: 1491: 1487: 1476: 1472: 1463: 1459: 1457: 1451: 1447: 1445: 1436: 1432: 1421: 1417: 1408: 1404: 1402: 1396: 1392: 1390: 1381: 1377: 1375: 1372: 1371: 1351: 1347: 1338: 1334: 1326: 1322: 1320: 1318: 1309: 1305: 1296: 1292: 1284: 1280: 1271: 1267: 1265: 1263: 1254: 1250: 1248: 1245: 1244: 1224: 1220: 1212: 1208: 1200: 1196: 1194: 1192: 1183: 1179: 1170: 1166: 1158: 1154: 1145: 1141: 1139: 1137: 1128: 1124: 1122: 1119: 1118: 1098: 1094: 1084: 1080: 1071: 1067: 1055: 1051: 1044: 1040: 1031: 1027: 1020: 1016: 1014: 1011: 1010: 974: 970: 961: 957: 948: 944: 942: 939: 938: 931:planetary gears 901: 897: 888: 884: 875: 871: 862: 858: 856: 853: 852: 832: 831: 821: 815: 811: 799: 795: 786: 782: 781: 777: 768: 764: 757: 753: 744: 740: 733: 729: 726: 725: 715: 709: 705: 692: 688: 679: 675: 674: 670: 661: 657: 650: 646: 637: 633: 626: 622: 618: 616: 613: 612: 598: 595: 592: 591: 589: 582: 579: 576: 575: 572: 570: 563: 560: 557: 556: 553: 551: 548:planetary gears 483: 458: 455: 454: 435: 431: 429: 426: 425: 398: 394: 385: 381: 379: 376: 375: 345: 341: 334: 330: 321: 317: 316: 314: 312: 309: 308: 288: 284: 282: 279: 278: 275: 266: 173: 80: 24: 17: 12: 11: 5: 6758: 6748: 6747: 6742: 6725: 6724: 6722: 6721: 6711: 6700: 6697: 6696: 6694: 6693: 6688: 6683: 6678: 6676:Electric motor 6672: 6670: 6666: 6665: 6663: 6662: 6661: 6660: 6655: 6650: 6645: 6640: 6635: 6630: 6625: 6615: 6614: 6613: 6608: 6603: 6593: 6587: 6585: 6581: 6580: 6578: 6577: 6572: 6567: 6562: 6557: 6552: 6547: 6542: 6537: 6532: 6527: 6522: 6517: 6512: 6507: 6502: 6497: 6492: 6490:Friction drive 6487: 6485:Fluid coupling 6482: 6477: 6472: 6467: 6462: 6457: 6452: 6447: 6442: 6437: 6432: 6427: 6422: 6417: 6412: 6406: 6404: 6398: 6397: 6395: 6394: 6389: 6384: 6379: 6376:Plug-in hybrid 6369: 6364: 6359: 6353: 6351: 6345: 6344: 6335: 6332: 6331: 6324: 6323: 6316: 6309: 6301: 6292: 6291: 6289: 6288: 6283: 6278: 6273: 6268: 6263: 6258: 6253: 6247: 6245: 6241: 6240: 6237: 6236: 6234: 6233: 6227: 6225: 6219: 6218: 6216: 6215: 6210: 6205: 6200: 6195: 6189: 6187: 6180: 6176: 6175: 6173: 6172: 6167: 6162: 6157: 6152: 6147: 6142: 6136: 6134: 6130: 6129: 6127: 6126: 6121: 6115: 6113: 6109: 6108: 6106: 6105: 6100: 6095: 6090: 6085: 6080: 6074: 6072: 6068: 6067: 6065: 6064: 6059: 6054: 6052:Harmonic drive 6049: 6044: 6039: 6034: 6029: 6023: 6021: 6017: 6016: 6009: 6008: 6001: 5994: 5986: 5980: 5979: 5967: 5962: 5957: 5952: 5947: 5942: 5937: 5929: 5928:External links 5926: 5923: 5922: 5909: 5896: 5882: 5868: 5857:(3): 448–453. 5841: 5814:(3): 756–767. 5798: 5780: 5765: 5739: 5717: 5695: 5674: 5617: 5610: 5590: 5583: 5561: 5541: 5525: 5506: 5505: 5503: 5500: 5498: 5497: 5491: 5488:Sturmey Archer 5485: 5480: 5474: 5469: 5464: 5459: 5453: 5451:Harmonic drive 5448: 5443: 5437: 5432: 5427: 5421: 5415: 5409: 5407: 5404: 5400: 5399: 5392: 5385: 5383: 5376: 5369: 5367: 5360: 5358: 5355: 5348: 5345: 5344: 5343: 5341: 5338: 5307: 5306: 5257: 5255: 5248: 5242: 5239: 5200: 5197: 5187: 5184: 5148:stepped-planet 5124: 5121: 5120: 5119: 5107: 5104: 5101: 5098: 5095: 5086: 5082: 5079: 5070: 5058: 5057: 5045: 5041: 5037: 5034: 5031: 5028: 5025: 5016: 5012: 5003: 4991: 4990: 4978: 4975: 4971: 4967: 4964: 4955: 4951: 4942: 4910: 4905: 4895: 4891: 4888: 4885: 4874: 4873: 4856: 4852: 4843: 4839: 4836: 4827: 4823: 4820: 4817: 4814: 4811: 4792:CSS animations 4784: 4781: 4769: 4768: 4757: 4754: 4749: 4745: 4741: 4736: 4732: 4728: 4723: 4720: 4715: 4710: 4706: 4691: 4690: 4679: 4676: 4673: 4670: 4662: 4658: 4654: 4649: 4645: 4637: 4633: 4629: 4624: 4620: 4581: 4578: 4569: 4568: 4567: 4566: 4555: 4548: 4544: 4538: 4534: 4528: 4525: 4522: 4515: 4511: 4505: 4501: 4486: 4481: 4478: 4473: 4470: 4467: 4460: 4456: 4450: 4446: 4431: 4428: 4425: 4417: 4413: 4409: 4404: 4400: 4392: 4388: 4384: 4364: 4361: 4360: 4359: 4358: 4347: 4340: 4336: 4330: 4326: 4320: 4317: 4314: 4307: 4303: 4297: 4293: 4278: 4275: 4272: 4269: 4266: 4259: 4255: 4249: 4245: 4230: 4227: 4224: 4216: 4212: 4208: 4201: 4197: 4193: 4188: 4184: 4163: 4160: 4159: 4158: 4157: 4146: 4139: 4135: 4129: 4125: 4119: 4116: 4109: 4105: 4099: 4095: 4080: 4077: 4074: 4067: 4063: 4057: 4053: 4033: 4027: 4026: 4015: 4007: 4003: 3999: 3994: 3990: 3982: 3978: 3974: 3969: 3965: 3958: 3955: 3937: 3936: 3925: 3918: 3914: 3908: 3904: 3898: 3895: 3888: 3884: 3878: 3874: 3868: 3865: 3842: 3839: 3835: 3834: 3823: 3820: 3815: 3811: 3805: 3801: 3797: 3792: 3788: 3782: 3778: 3774: 3769: 3765: 3759: 3755: 3728: 3724: 3701: 3697: 3674: 3670: 3657: 3656: 3640: 3636: 3632: 3627: 3623: 3616: 3612: 3604: 3600: 3596: 3593: 3588: 3584: 3573: 3558: 3554: 3548: 3544: 3536: 3532: 3528: 3523: 3519: 3508: 3493: 3489: 3482: 3478: 3474: 3469: 3465: 3456: 3452: 3448: 3445: 3440: 3436: 3425: 3410: 3406: 3399: 3395: 3391: 3386: 3382: 3373: 3369: 3365: 3362: 3357: 3353: 3342: 3326: 3322: 3318: 3313: 3309: 3302: 3298: 3290: 3286: 3282: 3279: 3274: 3270: 3259: 3244: 3240: 3234: 3230: 3222: 3218: 3214: 3209: 3205: 3187: 3184: 3183: 3182: 3165: 3146: 3116: 3107: 3088: 3058: 3049: 3037: 3036: 3019: 2987: 2978: 2947: 2929: 2920: 2908: 2907: 2890: 2858: 2849: 2818: 2800: 2791: 2775: 2772: 2767:Sturmey-Archer 2747: 2732: 2720: 2716: 2707: 2670: 2658: 2654: 2645: 2641: 2632: 2610: 2595: 2591: 2582: 2570: 2563: 2559: 2546: 2534: 2525: 2522: 2518: 2513: 2509: 2486: 2471: 2459: 2455: 2446: 2437: 2425: 2413: 2404: 2401: 2366: 2354: 2345: 2333: 2332: 2310: 2298: 2280: 2258: 2246: 2237: 2170: 2158: 2124: 2053: 2040: 2028: 2019: 1992: 1963: 1938: 1937: 1915: 1903: 1894: 1891: 1877: 1876: 1865: 1862: 1853: 1848: 1845: 1842: 1839: 1836: 1833: 1830: 1821: 1816: 1813: 1810: 1807: 1804: 1801: 1792: 1787: 1764: 1754: 1749: 1746: 1737: 1733: 1724: 1691: 1688: 1679: 1658: 1646: 1642: 1633: 1621: 1620: 1600: 1596: 1587: 1574: 1570: 1561: 1553: 1542: 1530: 1522: 1508: 1507: 1490: 1475: 1471: 1462: 1450: 1444: 1435: 1420: 1416: 1407: 1395: 1389: 1380: 1368: 1367: 1350: 1337: 1325: 1317: 1308: 1295: 1283: 1279: 1270: 1262: 1253: 1241: 1240: 1223: 1211: 1199: 1191: 1182: 1169: 1157: 1153: 1144: 1136: 1127: 1115: 1114: 1097: 1092: 1083: 1079: 1070: 1066: 1063: 1054: 1043: 1039: 1030: 1019: 1004: 1003: 973: 969: 960: 956: 947: 900: 896: 887: 883: 874: 870: 861: 846: 845: 830: 827: 824: 822: 814: 808: 798: 794: 785: 780: 776: 767: 756: 752: 743: 732: 728: 727: 724: 721: 718: 716: 708: 702: 691: 687: 678: 673: 669: 660: 649: 645: 636: 625: 621: 620: 540: 539: 521: 508: 498: 482: 479: 462: 434: 397: 393: 384: 370: 369: 358: 355: 344: 333: 329: 320: 287: 274: 271: 213:used rotating 172: 169: 79: 76: 44:gear reduction 15: 9: 6: 4: 3: 2: 6757: 6746: 6743: 6741: 6738: 6737: 6735: 6720: 6712: 6710: 6706: 6702: 6701: 6698: 6692: 6689: 6687: 6684: 6682: 6679: 6677: 6674: 6673: 6671: 6667: 6659: 6656: 6654: 6651: 6649: 6646: 6644: 6641: 6639: 6636: 6634: 6631: 6629: 6626: 6624: 6621: 6620: 6619: 6616: 6612: 6609: 6607: 6604: 6602: 6599: 6598: 6597: 6594: 6592: 6589: 6588: 6586: 6582: 6576: 6573: 6571: 6568: 6566: 6563: 6561: 6558: 6556: 6553: 6551: 6550:Shift-by-wire 6548: 6546: 6543: 6541: 6538: 6536: 6533: 6531: 6528: 6526: 6523: 6521: 6518: 6516: 6513: 6511: 6508: 6506: 6503: 6501: 6498: 6496: 6493: 6491: 6488: 6486: 6483: 6481: 6478: 6476: 6473: 6471: 6468: 6466: 6463: 6461: 6458: 6456: 6453: 6451: 6448: 6446: 6443: 6441: 6438: 6436: 6433: 6431: 6428: 6426: 6423: 6421: 6418: 6416: 6413: 6411: 6408: 6407: 6405: 6403: 6399: 6393: 6390: 6388: 6387:Petrol engine 6385: 6383: 6380: 6377: 6373: 6370: 6368: 6365: 6363: 6360: 6358: 6357:Diesel engine 6355: 6354: 6352: 6350: 6346: 6342: 6340: 6333: 6329: 6322: 6317: 6315: 6310: 6308: 6303: 6302: 6299: 6287: 6284: 6282: 6279: 6277: 6274: 6272: 6269: 6267: 6264: 6262: 6259: 6257: 6254: 6252: 6249: 6248: 6246: 6242: 6232: 6229: 6228: 6226: 6224: 6220: 6214: 6211: 6209: 6206: 6204: 6201: 6199: 6196: 6194: 6191: 6190: 6188: 6184: 6181: 6177: 6171: 6168: 6166: 6163: 6161: 6158: 6156: 6153: 6151: 6148: 6146: 6143: 6141: 6138: 6137: 6135: 6131: 6125: 6122: 6120: 6117: 6116: 6114: 6110: 6104: 6101: 6099: 6096: 6094: 6091: 6089: 6086: 6084: 6081: 6079: 6076: 6075: 6073: 6069: 6063: 6060: 6058: 6055: 6053: 6050: 6048: 6045: 6043: 6040: 6038: 6035: 6033: 6030: 6028: 6025: 6024: 6022: 6018: 6014: 6007: 6002: 6000: 5995: 5993: 5988: 5987: 5984: 5978: 5974: 5971: 5968: 5966: 5963: 5961: 5960:Prius Gearbox 5958: 5956: 5953: 5951: 5948: 5946: 5943: 5941: 5938: 5935: 5932: 5931: 5919: 5913: 5906: 5900: 5892: 5886: 5878: 5872: 5864: 5860: 5856: 5852: 5845: 5837: 5833: 5829: 5825: 5821: 5817: 5813: 5809: 5802: 5794: 5790: 5784: 5776: 5772: 5768: 5766:9780802016379 5762: 5758: 5753: 5752: 5743: 5737: 5733: 5728: 5724: 5720: 5714: 5710: 5706: 5699: 5688: 5681: 5679: 5663: 5659: 5655: 5651: 5647: 5643: 5639: 5635: 5628: 5621: 5613: 5611:0-34-056831-3 5607: 5603: 5602: 5594: 5586: 5584:0-74-870531-7 5580: 5576: 5572: 5565: 5557: 5553: 5552: 5545: 5538: 5532: 5530: 5522: 5516: 5514: 5512: 5507: 5495: 5492: 5489: 5486: 5484: 5481: 5478: 5475: 5473: 5470: 5468: 5465: 5463: 5460: 5457: 5454: 5452: 5449: 5447: 5444: 5441: 5438: 5436: 5433: 5431: 5428: 5425: 5422: 5419: 5416: 5414: 5411: 5410: 5396: 5389: 5384: 5380: 5373: 5368: 5364: 5359: 5352: 5347: 5346: 5337: 5334: 5329: 5325: 5322: 5313: 5303: 5300: 5292: 5289:February 2021 5282: 5278: 5274: 5268: 5267: 5263: 5258:This section 5256: 5252: 5247: 5246: 5238: 5234: 5230: 5226: 5222: 5218: 5210: 5205: 5196: 5194: 5183: 5181: 5176: 5172: 5167: 5165: 5159: 5155: 5153: 5149: 5145: 5144:meshed-planet 5137: 5134: 5129: 5102: 5099: 5096: 5084: 5080: 5077: 5068: 5060: 5059: 5043: 5039: 5032: 5029: 5026: 5014: 5010: 5001: 4993: 4992: 4973: 4969: 4965: 4953: 4949: 4940: 4932: 4931: 4930: 4927: 4908: 4903: 4893: 4889: 4886: 4883: 4854: 4850: 4841: 4837: 4834: 4825: 4818: 4815: 4812: 4802: 4801: 4800: 4793: 4789: 4780: 4777: 4772: 4755: 4747: 4743: 4739: 4734: 4730: 4721: 4718: 4713: 4708: 4704: 4696: 4695: 4694: 4677: 4674: 4671: 4668: 4660: 4656: 4652: 4647: 4643: 4635: 4631: 4627: 4622: 4618: 4607: 4606: 4605: 4602: 4600: 4595: 4586: 4577: 4575: 4553: 4546: 4542: 4536: 4532: 4526: 4523: 4520: 4513: 4509: 4503: 4499: 4484: 4479: 4476: 4471: 4468: 4465: 4458: 4454: 4448: 4444: 4429: 4426: 4423: 4415: 4411: 4407: 4402: 4398: 4390: 4386: 4382: 4372: 4371: 4370: 4369: 4368: 4345: 4338: 4334: 4328: 4324: 4318: 4315: 4312: 4305: 4301: 4295: 4291: 4276: 4273: 4270: 4267: 4264: 4257: 4253: 4247: 4243: 4228: 4225: 4222: 4214: 4210: 4206: 4199: 4195: 4191: 4186: 4182: 4171: 4170: 4169: 4168: 4167: 4144: 4137: 4133: 4127: 4123: 4117: 4114: 4107: 4103: 4097: 4093: 4078: 4075: 4072: 4065: 4061: 4055: 4051: 4041: 4040: 4039: 4038: 4037: 4030: 4013: 4005: 4001: 3997: 3992: 3988: 3980: 3976: 3972: 3967: 3963: 3956: 3953: 3946: 3945: 3944: 3940: 3923: 3916: 3912: 3906: 3902: 3896: 3893: 3886: 3882: 3876: 3872: 3866: 3863: 3856: 3855: 3854: 3852: 3847: 3838: 3821: 3818: 3813: 3809: 3803: 3799: 3795: 3790: 3786: 3780: 3776: 3772: 3767: 3763: 3757: 3753: 3745: 3744: 3743: 3726: 3722: 3699: 3695: 3672: 3668: 3638: 3634: 3630: 3625: 3621: 3614: 3610: 3602: 3598: 3594: 3591: 3586: 3582: 3574: 3556: 3552: 3546: 3542: 3534: 3530: 3526: 3521: 3517: 3509: 3491: 3487: 3480: 3476: 3472: 3467: 3463: 3454: 3450: 3446: 3443: 3438: 3434: 3426: 3408: 3404: 3397: 3393: 3389: 3384: 3380: 3371: 3367: 3363: 3360: 3355: 3351: 3343: 3324: 3320: 3316: 3311: 3307: 3300: 3296: 3288: 3284: 3280: 3277: 3272: 3268: 3260: 3242: 3238: 3232: 3228: 3220: 3216: 3212: 3207: 3203: 3195: 3194: 3193: 3163: 3144: 3114: 3105: 3086: 3056: 3047: 3039: 3038: 3017: 2985: 2976: 2945: 2927: 2918: 2910: 2909: 2888: 2856: 2847: 2816: 2798: 2789: 2781: 2780: 2779: 2768: 2763: 2759: 2745: 2730: 2718: 2714: 2705: 2691: 2686: 2684: 2668: 2656: 2652: 2643: 2639: 2630: 2608: 2593: 2589: 2580: 2568: 2561: 2557: 2544: 2532: 2523: 2520: 2516: 2511: 2507: 2497: 2484: 2469: 2457: 2453: 2444: 2435: 2423: 2411: 2402: 2399: 2388: 2364: 2352: 2343: 2308: 2296: 2281: 2256: 2244: 2235: 2226: 2225: 2224: 2168: 2156: 2122: 2111: 2109: 2105: 2051: 2038: 2026: 2017: 1990: 1961: 1949: 1947: 1943: 1913: 1901: 1892: 1889: 1882: 1881: 1880: 1863: 1860: 1851: 1843: 1840: 1837: 1831: 1828: 1819: 1811: 1808: 1805: 1799: 1790: 1785: 1778: 1777: 1776: 1762: 1752: 1747: 1744: 1735: 1731: 1722: 1711: 1709: 1705: 1689: 1686: 1677: 1656: 1644: 1640: 1631: 1598: 1594: 1585: 1572: 1568: 1559: 1551: 1540: 1528: 1520: 1513: 1512: 1511: 1488: 1473: 1469: 1460: 1448: 1442: 1433: 1418: 1414: 1405: 1393: 1387: 1378: 1370: 1369: 1348: 1335: 1323: 1315: 1306: 1293: 1281: 1277: 1268: 1260: 1251: 1243: 1242: 1221: 1209: 1197: 1189: 1180: 1167: 1155: 1151: 1142: 1134: 1125: 1117: 1116: 1095: 1081: 1077: 1068: 1061: 1052: 1041: 1037: 1028: 1017: 1009: 1008: 1007: 1002:respectively. 1001: 997: 993: 971: 967: 958: 954: 945: 936: 935:carrier frame 932: 928: 924: 920: 898: 894: 885: 881: 872: 868: 859: 851: 850: 849: 828: 825: 823: 812: 806: 796: 792: 783: 778: 774: 765: 754: 750: 741: 730: 722: 719: 717: 706: 700: 689: 685: 676: 671: 667: 658: 647: 643: 634: 623: 611: 610: 609: 549: 544: 537: 533: 529: 525: 522: 520: 516: 512: 509: 506: 502: 501:Carrier frame 499: 496: 493: 492: 491: 488: 478: 474: 460: 452: 432: 423: 421: 417: 395: 391: 382: 373: 356: 353: 342: 331: 327: 318: 307: 306: 305: 285: 270: 261: 256: 254: 251:invented the 250: 246: 242: 238: 236: 232: 228: 223: 221: 216: 212: 208: 207: 202: 201: 194: 192: 188: 184: 183: 178: 168: 161: 157: 153: 149: 147: 143: 139: 138:differentials 135: 130: 128: 124: 120: 116: 112: 108: 104: 100: 96: 92: 84: 75: 73: 69: 65: 60: 58: 54: 53:pitch circles 49: 45: 41: 37: 28: 22: 6628:Racing slick 6565:Transfer box 6535:Park-by-wire 6530:Parking pawl 6479: 6445:Differential 6420:Direct-drive 6402:Transmission 6392:Steam engine 6337:Part of the 6336: 6145:Differential 6140:Transmission 6093:Spiral bevel 6041: 5917: 5912: 5904: 5899: 5885: 5871: 5854: 5850: 5844: 5811: 5807: 5801: 5792: 5783: 5750: 5742: 5704: 5698: 5665:. Retrieved 5640:(1): 27–43. 5637: 5633: 5620: 5600: 5593: 5574: 5564: 5550: 5544: 5536: 5520: 5440:Ford Model T 5397:transmission 5330: 5326: 5318: 5295: 5286: 5271:Please help 5259: 5235: 5231: 5227: 5223: 5219: 5215: 5189: 5171:World War II 5168: 5160: 5156: 5151: 5147: 5143: 5141: 4928: 4875: 4797: 4775: 4773: 4770: 4692: 4603: 4598: 4591: 4570: 4362: 4161: 4031: 4028: 3941: 3938: 3848: 3844: 3836: 3658: 3189: 2777: 2687: 2498: 2389: 2334: 2112: 2107: 1950: 1945: 1941: 1939: 1878: 1712: 1707: 1703: 1622: 1509: 1005: 999: 995: 991: 934: 930: 926: 922: 847: 607: 547: 536:Annular gear 535: 532:Annulus gear 531: 527: 523: 518: 514: 510: 504: 500: 494: 484: 475: 453: 424: 419: 415: 374: 371: 276: 257: 239: 224: 204: 197: 195: 180: 174: 165: 159: 131: 126: 122: 118: 114: 110: 102: 94: 90: 89: 67: 64:annulus gear 63: 61: 39: 35: 33: 6606:Alloy wheel 6465:Drive wheel 6455:Drive shaft 6415:Chain drive 6271:Chain drive 6231:Wheel train 6103:Herringbone 5321:3D printing 5241:3D printing 2688:In bicycle 1000:planet gear 998:, and each 511:Planet gear 267: 1650 220:epitrochoid 105:, gears or 72:gear ratios 6734:Categories 6691:Alternator 6339:Automobile 6328:Powertrain 6266:Belt drive 6251:Ball screw 6198:Derailleur 6032:Worm drive 5793:buseco.net 5775:1036858215 5736:1568986815 5727:1036836698 5502:References 5435:Epicycloid 5395:Ravigneaux 5199:Advantages 3851:gear train 487:gear ratio 191:precession 142:bevel gear 57:epicycloid 6560:Transaxle 6525:Manumatic 6495:Gearshift 6367:Fuel cell 6281:Freewheel 6261:Jackscrew 6256:Leadscrew 6133:Mechanics 5494:Uni Wheel 5260:does not 5100:− 5085:ω 5081:− 5069:ω 5030:− 5015:ω 5002:ω 4954:ω 4941:ω 4890:− 4855:ω 4851:− 4842:ω 4826:ω 4816:− 4776:ring gear 4744:ω 4731:ω 4705:ω 4672:− 4657:ω 4653:− 4644:ω 4632:ω 4628:− 4619:ω 4510:ω 4500:ω 4472:− 4455:ω 4445:ω 4412:ω 4408:− 4399:ω 4387:ω 4383:− 4302:ω 4292:ω 4271:− 4254:ω 4244:ω 4211:ω 4207:− 4196:ω 4192:− 4183:ω 4118:− 4104:ω 4094:ω 4062:ω 4052:ω 4002:ω 3998:− 3989:ω 3977:ω 3973:− 3964:ω 3897:− 3883:ω 3873:ω 3810:ω 3800:τ 3787:ω 3777:τ 3764:ω 3754:τ 3723:τ 3696:τ 3669:τ 3599:τ 3595:− 3583:τ 3531:τ 3518:τ 3451:τ 3447:− 3435:τ 3368:τ 3364:− 3352:τ 3285:τ 3281:− 3269:τ 3217:τ 3204:τ 3164:α 3106:α 3048:α 3018:α 2986:− 2977:α 2919:α 2889:α 2857:− 2848:α 2790:α 2690:hub gears 2344:− 2236:− 2104:clockwise 2018:− 1852:ω 1829:− 1820:ω 1791:ω 1678:ω 1645:ω 1641:≠ 1632:ω 1599:ω 1595:− 1586:ω 1573:ω 1569:− 1560:ω 1521:− 1489:ω 1434:ω 1379:ω 1349:ω 1316:− 1307:ω 1252:ω 1222:ω 1190:− 1181:ω 1126:ω 1096:ω 1053:ω 1029:ω 992:ring gear 923:ring gear 899:ω 886:ω 873:ω 860:ω 813:ω 793:− 775:− 766:ω 751:− 742:ω 707:ω 668:− 659:ω 635:ω 528:Moon gear 524:Ring gear 519:ring gear 505:planetary 420:ring gear 260:Desargues 253:bookwheel 156:Bookwheel 115:sun wheel 6719:Category 6658:Tubeless 6643:Run-flat 6623:Off-road 6440:Coupling 6362:Electric 6244:See also 6223:Horology 6213:Sprocket 6203:Hub gear 6186:Bicycles 6179:Examples 6150:Coupling 6119:Involute 5973:Archived 5662:54663891 5456:Hub gear 5406:See also 2683:tractors 2085:⁠− 2066:⁠− 1623:only if 996:sun gear 927:sun gear 917:are the 571:⁠− 552:⁠− 517:and the 515:sun gear 495:Sun gear 418:and the 416:sun gear 206:Almagest 203:(a.k.a. 182:Almagest 125:gear or 111:sun gear 78:Overview 6124:Cycloid 6098:Helical 6020:Systems 5836:4986932 5816:Bibcode 5687:Gearing 5642:Bibcode 5446:Gearbox 5340:Gallery 5281:removed 5266:sources 5169:During 3660:where: 2221:⁠ 2209:⁠ 2205:⁠ 2193:⁠ 2100:⁠ 2081:⁠ 921:of the 602:⁠ 590:⁠ 586:⁠ 567:⁠ 179:in the 171:History 146:coaxial 127:annulus 119:carrier 107:pinions 59:curve. 42:) is a 6709:Portal 6669:Hybrid 6633:Radial 6611:Hubcap 6425:Clutch 6372:Hybrid 6341:series 6193:Cogset 6170:Offset 6071:Shapes 5834:  5773:  5763:  5734:  5725:  5715:  5667:20 May 5660:  5608:  5581:  5212:angle. 4876:where 2743:  2666:  2482:  1946:output 1942:inputs 1879:where 1708:output 1654:  994:, the 933:, and 848:where 372:where 162:, 1588 103:planet 6745:Gears 6653:Spare 6596:Wheel 6500:Giubo 6155:Train 6088:Crown 6083:Bevel 6013:Gears 5832:S2CID 5690:(PDF) 5658:S2CID 5630:(PDF) 5426:(CVT) 5175:radar 4367:=0, 4166:=0, 4036:=0, 2207:, or 2083:, or 1704:input 569:, or 534:, or 97:is a 48:gears 6648:Snow 6638:Rain 6618:Tire 6078:Spur 5771:OCLC 5761:ISBN 5732:ISBN 5723:OCLC 5713:ISBN 5669:2014 5606:ISBN 5579:ISBN 5264:any 5262:cite 1510:and 485:The 198:The 136:and 123:ring 99:gear 6601:Rim 5859:doi 5855:120 5824:doi 5650:doi 5275:by 4693:or 2202:64 2078:16 1682:... 564:16 209:), 113:or 93:or 34:An 6736:: 5853:. 5830:. 5822:. 5812:21 5810:. 5791:. 5769:. 5759:. 5757:69 5721:. 5711:. 5709:19 5677:^ 5656:. 5648:. 5638:32 5636:. 5632:. 5573:. 5554:. 5528:^ 5510:^ 5182:. 4592:A 4576:. 4491:so 4436:or 4283:so 4235:or 4085:so 2218:4 2196:16 2097:2 2072:24 929:, 925:, 599:2 583:2 558:24 530:, 526:, 269:. 264:c. 222:. 148:. 6378:) 6374:( 6320:e 6313:t 6306:v 6005:e 5998:t 5991:v 5879:. 5865:. 5861:: 5838:. 5826:: 5818:: 5795:. 5777:. 5729:. 5671:. 5652:: 5644:: 5614:. 5587:. 5302:) 5296:( 5291:) 5287:( 5283:. 5269:. 5106:) 5103:1 5097:R 5094:( 5089:c 5078:= 5073:s 5044:R 5040:/ 5036:) 5033:1 5027:R 5024:( 5019:c 5011:= 5006:r 4977:) 4974:R 4970:/ 4966:1 4963:( 4958:s 4950:= 4945:r 4913:s 4909:N 4904:/ 4898:r 4894:N 4887:= 4884:R 4859:s 4846:r 4838:R 4835:= 4830:c 4822:) 4819:1 4813:R 4810:( 4756:. 4753:) 4748:r 4740:+ 4735:s 4727:( 4722:2 4719:1 4714:= 4709:c 4678:, 4675:1 4669:= 4661:c 4648:r 4636:c 4623:s 4599:R 4554:. 4547:r 4543:N 4537:s 4533:N 4527:+ 4524:1 4521:= 4514:c 4504:r 4485:, 4480:R 4477:1 4469:1 4466:= 4459:c 4449:r 4430:, 4427:R 4424:= 4416:c 4403:r 4391:c 4365:s 4346:. 4339:s 4335:N 4329:r 4325:N 4319:+ 4316:1 4313:= 4306:c 4296:s 4277:, 4274:R 4268:1 4265:= 4258:c 4248:s 4229:, 4226:R 4223:= 4215:c 4200:c 4187:s 4164:r 4145:. 4138:s 4134:N 4128:r 4124:N 4115:= 4108:r 4098:s 4079:, 4076:R 4073:= 4066:r 4056:s 4034:c 4014:. 4006:c 3993:r 3981:c 3968:s 3957:= 3954:R 3924:. 3917:s 3913:N 3907:r 3903:N 3894:= 3887:r 3877:s 3867:= 3864:R 3822:0 3819:= 3814:s 3804:s 3796:+ 3791:c 3781:c 3773:+ 3768:r 3758:r 3727:c 3700:s 3673:r 3639:s 3635:N 3631:+ 3626:r 3622:N 3615:s 3611:N 3603:c 3592:= 3587:s 3557:r 3553:N 3547:s 3543:N 3535:r 3527:= 3522:s 3492:s 3488:N 3481:s 3477:N 3473:+ 3468:r 3464:N 3455:s 3444:= 3439:c 3409:r 3405:N 3398:s 3394:N 3390:+ 3385:r 3381:N 3372:r 3361:= 3356:c 3325:s 3321:N 3317:+ 3312:r 3308:N 3301:r 3297:N 3289:c 3278:= 3273:r 3243:s 3239:N 3233:r 3229:N 3221:s 3213:= 3208:r 3168:r 3155:r 3150:N 3145:+ 3140:s 3135:N 3127:r 3122:N 3115:+ 3110:s 3097:r 3092:N 3087:+ 3082:s 3077:N 3069:s 3064:N 3057:= 3052:c 3022:s 3010:r 3005:N 2998:s 2993:N 2981:c 2969:r 2964:N 2956:r 2951:N 2946:+ 2941:s 2936:N 2928:= 2923:r 2893:r 2881:s 2876:N 2869:r 2864:N 2852:c 2840:s 2835:N 2827:r 2822:N 2817:+ 2812:s 2807:N 2799:= 2794:s 2746:. 2735:r 2731:N 2723:r 2719:N 2715:+ 2710:s 2706:N 2669:. 2661:r 2657:N 2653:+ 2648:s 2644:N 2640:: 2635:s 2631:N 2609:, 2598:r 2594:N 2590:+ 2585:s 2581:N 2573:s 2569:N 2562:= 2558:) 2549:s 2545:N 2537:r 2533:N 2524:+ 2521:1 2517:( 2512:/ 2508:1 2485:. 2474:s 2470:N 2462:r 2458:N 2454:+ 2449:s 2445:N 2436:= 2428:s 2424:N 2416:r 2412:N 2403:+ 2400:1 2369:r 2365:N 2357:s 2353:N 2313:r 2309:N 2301:p 2297:N 2261:p 2257:N 2249:s 2245:N 2215:/ 2212:1 2199:/ 2173:r 2169:N 2161:p 2157:N 2127:r 2123:N 2094:/ 2091:3 2087:+ 2075:/ 2068:+ 2052:. 2043:p 2039:N 2031:s 2027:N 1995:p 1991:N 1966:s 1962:N 1918:p 1914:N 1906:s 1902:N 1893:= 1890:n 1864:0 1861:= 1856:c 1847:) 1844:n 1841:+ 1838:1 1835:( 1832:2 1824:r 1815:) 1812:n 1809:+ 1806:2 1803:( 1800:+ 1795:s 1786:n 1763:, 1757:p 1753:N 1748:2 1745:+ 1740:s 1736:N 1732:= 1727:r 1723:N 1690:0 1687:= 1657:. 1649:c 1636:r 1603:c 1590:r 1577:c 1564:s 1552:= 1545:s 1541:N 1533:r 1529:N 1493:r 1478:r 1474:N 1470:+ 1465:s 1461:N 1453:r 1449:N 1443:+ 1438:s 1423:r 1419:N 1415:+ 1410:s 1406:N 1398:s 1394:N 1388:= 1383:c 1353:s 1340:r 1336:N 1328:s 1324:N 1311:c 1298:r 1294:N 1286:r 1282:N 1278:+ 1273:s 1269:N 1261:= 1256:r 1226:r 1214:s 1210:N 1202:r 1198:N 1185:c 1172:s 1168:N 1160:r 1156:N 1152:+ 1147:s 1143:N 1135:= 1130:s 1100:c 1091:) 1086:r 1082:N 1078:+ 1073:s 1069:N 1065:( 1062:= 1057:r 1046:r 1042:N 1038:+ 1033:s 1022:s 1018:N 976:p 972:N 968:, 963:s 959:N 955:, 950:r 946:N 903:c 895:, 890:p 882:, 877:s 869:, 864:r 829:0 826:= 817:c 807:) 801:p 797:N 788:r 784:N 779:( 770:p 759:p 755:N 746:r 735:r 731:N 723:0 720:= 711:c 701:) 694:p 690:N 686:+ 681:s 677:N 672:( 663:p 652:p 648:N 644:+ 639:s 628:s 624:N 596:/ 593:3 580:/ 577:3 573:+ 561:/ 554:+ 461:A 437:p 433:n 400:r 396:N 392:, 387:s 383:N 357:A 354:= 347:p 343:n 336:r 332:N 328:+ 323:s 319:N 290:p 286:n 23:.

Index

Starter ring gear

gear reduction
gears
pitch circles
epicycloid
gear ratios

gear
pinions
pencil sharpeners
differentials
bevel gear
coaxial

Bookwheel
Claudius Ptolemy
Almagest
Antikythera Mechanism
precession
Mathematical Syntaxis
Almagest
Claudius Ptolemy
deferent and epicycles
epitrochoid
Antikythera Mechanism
ellipticity of its orbit
apsidal precession
Richard of Wallingford
astronomical clock

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