Torque multiplier

Abstract

Several examples of torque multipliers and related methods are disclosed. In one example, a torque multiplier includes: a first shaft to provide a first torque; a second shaft for providing a second torque; and a gear structure coupled to the first shaft and the second shaft to amplify the first torque to generate a second torque, the gear structure including a convex toothed ring, a plurality of rolling rings in contact with the convex toothed ring, a pin structure including a plurality of pins, each pin located within one rolling ring, and a bearing in contact with the plurality of rolling rings.

Description

[0001] Priority Claim

[0002] This application claims priority to U.S. Provisional Patent Application 63 / 425,781, filed on November 16, 2022, and titled "Mechanical Torque Multiplier with Enhanced Efficiency Using Hollow Rolling Elements", and U.S. Patent Application 18 / 510,640, filed on November 15, 2023, and titled "Torque Multiplier", both of which are incorporated herein by reference. Technical Field

[0003] Several examples of novel torque multipliers and their components are disclosed. Background Art

[0004] In the field of mechanical power transmission, rotating shafts, motors, or levers are commonly used to perform useful work or energy conversion. The speed or torque required by a load typically cannot be directly generated by a rotating power source. In these cases, it is necessary to convert a low-torque, high-speed rotation into a high-torque, low-speed rotation, or vice versa. Devices that perform this function are sometimes referred to as torque multipliers, transmissions, reducers, or mechanical drive systems or similar terms. When used herein, such devices are referred to as torque multipliers.

[0005] Torque multipliers allow motors or generators to operate at multiples of a given input torque. This allows designers to optimize the speed and torque characteristics required in rotating machinery applications. Generally, many applications require efficient rotational power conversion with a large speed ratio, a compact form factor, a hollow bore, a high torque density, or a low mass.

[0006] In the category of high-ratio torque multipliers, prior art torque multipliers have been introduced, but each torque multiplier has significant design trade-offs aimed at meeting market demands. Table 1 summarizes these prior art solutions.

[0007] Table 1: Overview of Prior Art Torque Multipliers

[0008]

[0009] Inefficient power transmission devices waste a significant amount of energy globally, particularly in the high-ratio category. Significantly improving the efficiency of torque multiplication would impact global emissions and allow for the creation of new high-performance motion devices. For example, an existing technology design in the art is known as a "cycloidal speed reducer". The "cycloidal speed reducer" has several well-known drawbacks. These drawbacks include expensive manufacturing to reduce backlash, limited hollow bore clearance, noise, vibration, and roughness, and low energy efficiency due to sliding interfaces. The latter is typically improved by adding bushings or bearings, increasing cost and complexity.

[0010] A new torque multiplier design is needed. SUMMARY OF THE INVENTION

[0011] The disclosed design provides a unique combination of performance, particularly the combination of high torque density, high efficiency, and high linearity with a large hollow hole. The disclosed torque multiplier has some similarities with existing cycloidal and other planetary gear devices with small tooth differences, but there are several substantial differences and improvements. For example, the typical cycloidal disk elements are replaced by multiple rolling rings, and the inner diameter of each rolling ring abuts against a torque pin, while the outer diameter of each rolling ring contacts and rolls against two teeth and an eccentric bearing. This innovation reduces inertia, friction, and distributes the load more evenly between the teeth, improving the load capacity and torque linearity.

[0012] The disclosed design combines the torque-generating tooth interface with the torque-transmitting stage through multiple rolling rings to increase torque density and reduce friction for a given number of parts. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 A plan view depicting the assembled torque multiplier.

[0014] Figure 2 An isometric view depicting the assembled torque multiplier.

[0015] Figure 3 A cross-section depicting the torque multiplier including the gear structure of the first embodiment.

[0016] Figure 4 An axial view depicting the gear structure of the first embodiment.

[0017] Figure 5 A depiction of the relative movement of certain components in the gear structure of the first embodiment.

[0018] Figure 6 An enlarged view depicting the gear structure of the first embodiment and showing the teeth of the tooth ring.

[0019] Figure 7 An enlarged view depicting the gear structure of the first embodiment and showing the reaction force vectors between the various components.

[0020] Figure 8 An axial view depicting the gear structure of the second embodiment.

[0021] Figure 9 An axial view depicting the gear structure of the third embodiment.

[0022] Figure 10 A depiction of the relative movement of certain components in the axial view of the gear structure of the fourth embodiment.

[0023] Figure 11 Axial view of the fifth embodiment depicting the gear structure.

[0024] Figure 12 Depicts a one-piece cage.

[0025] Figure 13 Isometric view of the sixth embodiment of the gear structure including a one-piece cage.

[0026] Figure 14 Isometric view of a two-piece cage.

[0027] Figure 15 Axial view of the seventh embodiment of the gear structure including a two-piece cage.

[0028] Figure 16 Another perspective view of the seventh embodiment of the gear structure.

[0029] Figure 17 Cross-section of a torque multiplier depicting two axially stacked gear structures.

[0030] Figure 18 Axial view of a torque multiplier depicting two axially stacked gear structures.

[0031] Figure 19 Exploded view of two axially stacked gear structures.

[0032] Figure 20 Cross-sectional view of the seventh embodiment of the gear structure.

[0033] Figure 21 Axial view of a torque multiplier depicting the eighth embodiment with a gear structure.

[0034] Figure 22 Depicts a method of operating a torque multiplier.

[0035] Figure 23 Depicts a system utilizing a torque multiplier. Detailed Description

[0036] Figure 1 Depicts a plan view of the torque multiplier 100 in an assembled form. The torque multiplier 100 includes a shaft 101, a shaft 102, and a housing 103. In a first mode, the shaft 101 receives an input torque and the shaft 102 delivers an output torque, where the output torque is N times greater than the input torque, where output torque = input torque * N. In a second mode, the shaft 102 receives an input torque and the shaft 101 delivers an output torque, where the output torque is N times smaller than the input torque, where output torque = input torque * (1 / N). The housing 103 encloses other components (not shown but described below) that provide torque multiplication between the shafts 101 and 102.

[0037] Figure 2 Shows an isometric view of the torque multiplier 100 in an assembled form. The shafts 101 and 102 and the housing 103 are shown again. The torque multiplier 100 also includes a plate 104 coupled to the housing 103.

[0038] Figure 3 Shows a cross-section of the torque multiplier 300, showing the shaft and bearing support of the assembly device with an eccentric bearing race. The torque multiplier 300 is an example of the torque multiplier 100 using the Figure 3 gear structure shown. The torque multiplier 300 includes shafts 301 and 302 ( Figures 1-2 examples of the shafts 101 and 102 in Figure 1 and Figure 2 examples of the housing 103 in Figure 2 and a plate 304 (

[0039] an example of the plate 104 in Figure 3 ). The torque multiplier 300 also includes a gear structure 305, which is the first embodiment of the gear structure disclosed herein and provides torque amplification between the shafts 301, 302 and the shaft support bearings 321, 322. Figure 3 The gear structure 305 includes a toothed ring 306, a rolling ring 307, a pin structure 308, and an eccentric bearing 309. The gear structure 305 is a circular or substantially circular device, which is

[0040] Figure 4 shown in side view when upright in Figure 4As shown in the example, the cam ring 306 is a ring with a circular or substantially circular outer circumference and a disk-shaped inner circumference. In this example, the shape is a modified hypocycloid shape, but other shapes can alternatively be used. The rolling rings 307 are a series of rings that are positioned inside and engage with the inner circumference of the cam ring 306, and are positioned outside and engage with the outer circumference of the outer race 310. The inner circumference of each rolling ring 307 engages with the pins in the pin structure 308. The pin structure 308 includes a plate with a series of pins, where each pin is placed inside the rolling ring 307. The pins are nominally circular, but the shape can be modified to increase clearance or improve performance. The eccentric bearing 309 is eccentric because it rotates with the shaft 301, which is an eccentric crankshaft. The outer race 310 engages with the rolling rings 307.

[0041] In one example, the pin structure 308 rotates, the cam ring 306 is fixed to a housing (not shown) and does not rotate, and the pin structure 308 is fixed to the shaft 302 (not shown), such that when the pin structure 308 rotates about the axis of the gear structure 305, it causes the shaft 302 to rotate about the axis. In another example, the cam ring 306 rotates, the pin structure 308 is fixed to a housing (not shown) and does not rotate, and the cam ring 306 is fixed to the shaft 302 (not shown), such that when the cam ring 308 rotates about the axis of the gear structure 305, it causes the shaft 302 to rotate about the axis.

[0042] Optionally, the gear structure 305 may include a cage (not shown, such as the cage 1013 in Figure 10 for holding the rolling elements 312 in relative positions to prevent jamming. Optionally, the gear structure 305 may include a cage (not shown, such as cages 1201 and 1401) for holding the rolling rings 307 in relative positions.

[0043] Figure 5Depicts the relative motion of certain components in the gear structure 305, where the lobed ring 306 is fixed to the housing and the pin structure 308 is fixed to the shaft 302. Shaft 301 is attached to the inner race 311. Shaft 301 will rotate in response to an input torque, which in this example is in the clockwise direction, and this will cause the inner race 311 to also rotate in the clockwise direction. The rolling elements 312 will rotate clockwise as a whole but will also rotate counterclockwise individually, enabling the outer race 310 to rotate freely counterclockwise under the push of contact with the rolling ring 307. The movement of the eccentric axis of the bearing 309 around the concentric axis of the shaft 301 will cause the rolling ring 307 to roll clockwise individually against the fixed lobed ring 306 while also rotating clockwise around the pin 308. The rolling ring assembly rotates as a whole with the pin structure 308 (in this example, the pin structure 308 is fixed to the shaft 302 (not shown), thus preventing the rolling ring from moving relative to the shaft 302 while allowing each rolling ring to pivot counterclockwise or clockwise and roll around the pin 308), which will cause the pin structure 308 and the shaft 302 to rotate counterclockwise.

[0044] Figure 6 Is an enlarged view of the gear structure 305 and shows the interaction of the lobed ring 306, the rolling ring 307, the pin structure 308, and the outer race 310, as well as the modified internal cycloidal teeth of the lobed ring 306. In this example, the inner circumference of the lobed ring 306 includes modified internal cycloidal teeth, but other shapes can also be used.

[0045] Figure 7 Is a further enlarged view of the gear structure 305 and shows the interaction of the lobed ring 306, a single rolling ring 307, the pin structure 308, and the outer race 310, and shows the reaction force vectors experienced by the rolling ring 307 when transmitting torque, as Figure 5 Shown and previously described. The reaction force vector 701 depicts the reaction force of the outer race 310 on the rolling ring 307, the reaction force vector 702 depicts the reaction force of the lobed ring 306 on the rolling ring 307, and the reaction force vector 703 depicts the reaction force of the pin structure 308 on the rolling ring 307. The tangential component of the reaction force 703 is the component that counteracts the load torque on the shaft 302 and the pin structure 308 in the previous example.

[0046] Now, additional embodiments of a gear structure operating according to similar principles as those already described for the gear structure 305 will be described.

[0047] Figure 8 Depicts the gear structure 805, which is a second embodiment of a gear structure and can be used to replace the Figure 3 Gear structure 305 in the torque multiplier 300. Figure 8Depicts an embodiment combining an elliptical bearing and a first amplification stage of a traction planetary gear, where the first amplification stage provides a further torque amplification factor of approximately 2. In this figure, the toothed ring 807 is driven by the flexible outer race 810 of the elliptical bearing. The gear structure 805 includes a toothed ring 806, a rolling ring 807, a pin structure 808, and an elliptical bearing 809. The elliptical bearing 809 includes an outer race 810 and rolling elements 812 that roll on an inner race integrated into the shaft 801. In this example, the shaft 801 is concentric rather than eccentric, and the outer race 810 is a flexible elliptical race such that its radius will move relative to the axis of the shaft 801. The rolling elements 812 do not all have the same diameter. That is, the rolling elements 812 include rolling elements of two or more diameters, optionally positioned by a cage (not shown). The size and position of the rolling elements 812 are designed to bend the outer race 810 into a non-circular shape, typically an ellipse. The shaft 801 is used in place of Figure 3 the shaft 301 in Figures 1-2 and is an example of the shaft 101 in

[0048] As Figure 8 shown, the toothed ring 806 is a ring with a circular or substantially circular outer perimeter and an inner perimeter that includes modified epicycloid teeth. The rolling ring 807 is a series of rings located within the inner perimeter of the toothed ring 806 and engaging the inner perimeter of the rolling ring 807. The pin structure 808 includes a plate with a series of pins, where each pin is placed within the rolling ring 807. The outer race 810 is a flexible ring that can continuously deform to accommodate the maximum radius, which occurs when the rolling rings 807 on opposite sides of the elliptical bearing 809 (e.g., Figure 8 the top and bottom rolling rings 808) are both located in the tooth valleys of the toothed ring 806 and are farthest from the central axis of the shaft 801. The outer race 810 engages the rolling ring 807. In this example, the teeth in the toothed ring 806 have a modified epicycloid shape, but other shapes can also be used, such as other disk shapes.

[0049] In one example, the pin structure 808 rotates, the toothed ring 806 is fixed to a housing (not shown) and does not rotate, and the pin structure 808 is fixed to an output shaft (not shown), such that when the pin structure 808 rotates about the axis of the shaft 801, it causes the output shaft to rotate about the axis. In another example, the toothed ring 806 rotates, the pin structure 808 is fixed to a housing (not shown) and does not rotate, and the toothed ring 806 is fixed to an output shaft (not shown), such that when the toothed ring 806 rotates about the axis of the shaft, it causes the output shaft to rotate about the axis.

[0050] Optionally, the gear structure 805 can include a cage (not shown, such as Figure 10the cage 1013). Optionally, the gear structure 805 may include a cage (not shown, such as cages 1201 and 1401) for holding the rolling rings 807 in relative positions to each other.

[0051] Figure 9 depicts a gear structure 905, which is a third embodiment of the gear structure and can be used to replace Figure 3 the gear structure 305 in the torque multiplier 300 in Figure 9 depicts an embodiment with a flexible eccentric bearing race. The gear structure 905 includes a lobed ring 906, rolling rings 907, a pin structure 908, and a bearing 909. The bearing 909 includes an outer race 910 and rolling elements 912. In this example, the shaft 901 is integral with an oval inner race, and the outer race 910 is a flexible race such that its radius will move along the profile of the oval race on the shaft 901 relative to the axis of the shaft 901 and is supported by the rolling elements 912. The shaft 901 is used to replace Figure 3 the shaft 301 in Figures 1-2 and is an example of the shaft 101 in

[0052] As Figure 9 shown, the lobed ring 906 is a ring with a circular or substantially circular outer perimeter and an inner perimeter that includes modified epicycloidal lobes. The rolling rings 907 are a series of rings located within the inner perimeter of the lobed ring 906 and engaging the inner perimeter of the rolling rings 907. The pin structure 908 includes a plate with a series of pins, where each pin is placed within the rolling rings 907. The bearing 909 is oval because its outer diameter moves relative to the axis of the shaft 301 due to the way the rolling rings 907 interact with the peaks and valleys of the inner perimeter of the lobed ring 906. The outer race 910 engages the rolling rings 907. In this example, the lobes in the lobed ring 906 have a modified epicycloidal shape, but other shapes, such as other disk shapes, may also be used.

[0053] In one example, the pin structure 908 rotates, the lobed ring 906 is fixed to a housing (not shown) without rotating, and the pin structure 908 is fixed to an output shaft (not shown) such that when the pin structure 908 rotates about the axis of the shaft 901, it causes the output shaft to rotate about the axis. In another example, the lobed ring 906 rotates, the pin structure 908 is fixed to a housing (not shown) without rotating, and the lobed ring 906 is fixed to an output shaft (not shown) such that when the lobed ring 902 rotates about the axis of the shaft, it causes the output shaft to rotate about the axis.

[0054] Optionally, the gear structure 905 may include a cage (not shown, such as Figure 10a cage (e.g., cage 1013). Optionally, the gear structure may include a cage (not shown, such as cages 1201 and 1401) for holding the rolling rings 907 in relative positions to each other.

[0055] Figure 10 depicts a gear structure 1005, which is a fourth embodiment of the gear structure and can be used to replace Figure 3 the gear structure 305 in the torque multiplier 300 in Figure 10 shows the relative movement of key components in a traction planetary gear eccentric drive embodiment, which is designed to provide a further torque amplification factor of about 2. The gear structure 1005 includes a toothed ring 1006, rolling rings 1007, a pin structure 1008, and a bearing 1009. The bearing 1009 includes an outer race 1010, rolling elements 1012, and a cage 1013. Not all of the rolling elements 1012 have the same diameter. That is, the rolling elements 1012 include rolling elements of two or more diameters. In this example, the shaft 1001 is concentric rather than eccentric, and the outer race 1010 is a circular race, but due to the different diameters of the rolling elements 1012, the movement of the outer race 1012 will be eccentric, such that its axis will move relative to the axis of the shaft 1001. The cage 1013 holds the rolling elements 1012 in position relative to each other and prevents jamming of the rolling elements 1012 that might occur in the absence of a cage. The shaft 1001 is used to replace Figure 3 the shaft 301 in Figures 1-2 and is an example of the shaft 101 in

[0056] As Figure 10 shown, the toothed ring 1006 is a ring with a circular outer circumference and an inner circumference including modified epicycloid teeth. The rolling rings 1007 are a series of rings located within the inner circumference of the toothed ring 1006 and engaging with the inner circumference of the rolling rings 1007. The pin structure 1008 includes a plate with a series of pins, where each pin is placed within the rolling rings 1007. The outer race 1010 engages with the rolling rings 1007. In this example, the teeth in the toothed ring 1006 have a modified epicycloid shape, but other shapes, such as other disk shapes, may also be used.

[0057] In one example, the pin structure 1008 rotates, the toothed ring 1006 is fixed to a housing (not shown) and does not rotate, and the pin structure 1008 is fixed to an output shaft (not shown), such that when the pin structure 1008 rotates about the axis of the shaft 1001, it causes the output shaft to rotate about the axis. In another example, the toothed ring 1006 rotates, the pin structure 1008 is fixed to a housing (not shown) and does not rotate, and the toothed ring 1006 is fixed to an output shaft (not shown), such that when the toothed ring 1006 rotates about the axis, it causes the output shaft to rotate about the axis.

[0058] Optionally, the gear structure may include a cage (not shown, such as cages 1201 and 1401) for holding the rolling rings 1007 in relative positions to each other.

[0059] Figure 11 A gear structure 1105 is depicted, which is a fifth embodiment of the gear structure and can be used to replace Figure 3 the gear structure 305 in the torque multiplier 300. Figure 11 A diagram of a compound arrangement is depicted, where two nested 6:1 strain wave stages are connected in series, and the total ratio calculated for the use of the high-speed shaft for the tooth ring 1106 attached to the low-speed shaft and the shaft 1101 is 36:1. The gear structure 1105 includes two stages, and each stage includes a flexible eccentric bearing race. The gear structure 1105 includes a tooth ring 1106, a rolling ring 1107, a pin structure 1108, a bearing 1109 (which includes an outer race 1110 and rolling elements 1112), a tooth ring 1116, a rolling ring 1117, a pin structure 1118, and a bearing 1119 (which includes an outer race 1120 and rolling elements 1122). The shaft 1101 engaged with the gear structure 1105 is also shown. The shaft 1101 is used to replace Figure 3 the shaft 301 in Figures 1-2 and is an example of the shaft 101 in

[0060] As Figure 11 shown, the tooth ring 1106 is a ring with a circular or substantially circular outer periphery and an inner periphery including modified epicycloid teeth. The rolling ring 1107 is a series of rings positioned within the inner periphery of the tooth ring 1106 and engaged with the outer periphery of the outer race 1110 and the pin structure 1108. The pin structure 1108 includes a plate having a series of pins, and each pin is placed within the rolling ring 1107. The bearing 1109 is elliptical because the inner race integrated into the tooth ring 1116 is elliptical. The outer race 1110 engages with the rolling ring 1107. In this example, the teeth in the tooth ring 1106 have a modified epicycloid shape, but other shapes, such as other disk shapes, may also be used.

[0061] The tooth ring 1116 is a ring having an elliptical or substantially elliptical outer periphery and an inner periphery including modified epicycloid teeth. The rolling ring 1117 is a series of rings positioned within the inner periphery of the tooth ring 1116 and engaged with the inner periphery of the tooth ring 1126. The pin structure 1118 includes a plate having a series of pins, and each pin is placed within the rolling ring 1117. The bearing 1119 is elliptical because the shaft 1101 has an integrated elliptical inner race. The outer race 1120 engages with the rolling ring 1117.

[0062] In one example, the pin structure 1108 and the pin structure 1118 are fixed together and rotate, while the toothed ring 1106 is fixed to a housing (not shown) without rotating, and the pin structure 1108 is fixed to an output shaft (not shown), such that when the pin structure 1108 rotates about the axis of the shaft 1101, it causes the output shaft to rotate about the axis. In another example, the toothed ring 1106 rotates, the pin structure 1108 and the pin structure 1118 are fixed to a housing (not shown) without rotating, and the toothed ring 1106 is fixed to an output shaft (not shown), such that when the toothed ring 1104 rotates about the axis of the shaft, it causes the output shaft to rotate about the axis.

[0063] Optionally, the gear structure 1105 may include a cage (not shown, such as the cage 1013 in Figure 10 ), for holding the rolling elements 1112 in relative positions to each other, and a cage for holding the rolling elements 1122 in relative positions to each other to prevent jamming. Optionally, the gear structure 1105 may include a cage (not shown, such as cages 1201 and 1401) for holding the rolling rings 1107 in relative positions to each other, and a cage for holding the rolling rings 1117 in relative positions to each other.

[0064] Figure 12 A perspective view of the cage 1201 with a one-piece design is depicted.

[0065] Figure 13 A gear structure 1305 is depicted, which is a sixth embodiment of the gear structure and can be used to replace the gear structure 305 in the torque multiplier 300 in Figure 3 . Figure 13 A perspective view of a one-piece cage is shown, with various components removed for clarity. The gear structure 1305 includes a cage 1201, rolling rings 1307, and a pin structure 1308. The gear structure 1305 engages with the shaft 1301. Each rolling ring 1307 is placed through an opening in the cage 1201. During operation, the cage 1201 holds the rolling rings 1307 in position relative to each other such that the rolling rings do not move significantly closer to or farther away from each other. For example, when the rolling rings are at the peaks of the inner circumference of a toothed ring (not shown), without the cage 1201, they may move laterally.

[0066] Figure 14 A perspective view of the cage 1401 with a two-piece design is depicted.

[0067] Figure 15 A gear structure 1505 is depicted, which is a seventh embodiment of the gear structure and can be used to replace the gear structure 305 in the torque multiplier 300 in Figure 3 . Figure 15Depicts an end view of a two-piece cage. The gear structure 1505 includes a cage 1401, rolling rings 1507, and a pin structure 1508. The gear structure 1505 engages with a shaft 1501. Each rolling ring 1507 is placed through an opening in the cage 1401. During operation, the cage 1401 holds the rolling rings 1507 in position relative to each other such that the rolling rings do not move significantly closer to or farther away from each other. For example, when the rolling rings are at the peaks of the inner circumference of a toothed ring (not shown), without the cage 1401, they may move laterally.

[0068] Figure 16 Depicts a perspective view of the gear structure 1505, with individual components removed for clarity, and includes a two-piece cage. The cage 1401, rolling rings 1507, pin structure 1508, and shaft 1501 are depicted.

[0069] Figure 17 Depicts a torque multiplier 1700. The torque multiplier 1700 is an example of a torque multiplier 100 that uses Figure 17 the gear structure shown. Figure 17 Depicts a cross-section showing the shaft and bearing support of an assembly device having two axially stacked groups of components that are offset 180 degrees and that operate kinematically in parallel. The torque multiplier 1700 includes shafts 1701 and 1702 ( Figures 1-2 examples of shafts 101 and 102 in Figure 1 and Figure 2 ), a housing 1703 ( Figure 2 an example of housing 103 in

[0070] Figure 18 ), and a plate 1704 ( Figure 2 an example of plate 104 in ). The torque multiplier 1700 also includes gear structures 1705 and 1706 that are axially stacked and are 180 degrees out of phase with each other. In a first mode, shaft 1701 drives gear structure 1705, gear structure 1705 in turn drives gear structure 1706, and gear structure 1706 in turn drives shaft 1702. In a second mode, shaft 1702 drives gear structure 1706, gear structure 1706 in turn drives gear structure 1705, and gear structure 1705 in turn drives shaft 1701. The gear structures 1705 and 1706 can include any one of the gear structures 305, 805, 905, 1005, 1105, 1305, and 1505 described previously. In this example, shaft 1701 is a two-plane crankshaft, and the gear structures 1705 and 1706 are 180 degrees out of phase with each other to balance the mass about the axis of shaft 1701 and to balance the reaction forces of the entire device. This stacking concept can be extended to three-gear structures or four-gear structures or more, depending on the requirements of the application.Depicts another perspective of the torque multiplier 1700. Figure 18 Shows an end view of a device having two axially stacked groups of components offset 180 degrees from each other, with some components removed for clarity. Components of the shaft 1701 and the gear structures 1705 and 1706 are depicted. The gear structure 1705 includes a toothed ring 1806, and the gear structure 1706 includes a toothed ring 1816. As shown, the toothed rings 1806 and 1816 are out of phase with each other.

[0071] Figure 19 Depicts an exploded view of the torque multiplier 1700. Figure 19 Shows a device having two axially stacked groups of components offset 180 degrees from each other. The torque multiplier 1700 includes a shaft 1701, a shaft 1702, a housing 1703, a plate 1704, a gear structure 1705, and a gear structure 1706. The gear structure 1705 includes a bearing 1809, a rolling ring 1807, and a toothed ring 1806. The gear structure 1706 includes a bearing 1819, a rolling ring 1817, and a toothed ring 1816. Each of the bearings 1809 and 1819 includes rolling elements (not shown) and one or more raceways in which the rolling elements are placed.

[0072] Optionally, each of the gear structures 1705 and 1705 may include a cage (not shown, such as Figure 10 the cage 1013 in ) for holding the rolling elements (not shown) in relative positions with respect to each other to prevent jamming. Optionally, each of the gear structures 1705 and 1706 may include a cage (not shown, such as cages 1201 and 1401) for holding the rolling rings 1807 and 1817 in relative positions with respect to each other, respectively.

[0073] Figure 20 Depicts the gear structure 2005, which is the eighth embodiment of the gear structure. Figure 20 Depicts a cross-sectional view showing a wheel drive application in which the toothed ring rotates and the pins are stationary. The gear structure 2005 includes the toothed ring 2006, the rolling ring 2007, the pin structure 2008, and the cage 1401 described previously.

[0074] Optionally, the gear structure 2005 may include a cage (as shown, such as cages 1201 and 1401) for holding the rolling ring 2007 in relative positions with respect to each other.

[0075] Figure 21 Depicts a torque multiplier having the eighth embodiment of the gear structure. The torque multiplier 2100 is an example of the torque multiplier 100 using Figure 21 the gear structure shown. Figure 21Use an eccentric bearing 2109. The torque multiplier 2100 includes a low-speed shaft 2101 and a high-speed shaft 2102 (which are Figures 1-2 examples of the intermediate shafts 101 and 102), a substantially epicyclic convex tooth ring 2106, a rolling ring 2107, a pin structure 2108, an eccentric bearing 2109, and a cage 2113. The bearing 2109 includes an outer race 2110 (eccentric), an inner race 2111 (eccentric), and rolling elements 2112. The cage 2113 holds the rolling rings 2107 in their relative positions to each other. Optionally, the torque multiplier 2100 may include a cage (not shown, such as Figure 10 the cage 1013) for holding the rolling elements 2112 in their relative positions to each other to prevent jamming.

[0076] It should be noted that in some of the above examples, the input shaft is a crankshaft, or an inverted hollow crankshaft as Figure 21 shown. One of ordinary skill in the art will understand that alternatively, the output shaft may be a crankshaft, and the relationship between the shafts and the components may be reversed compared to these examples. One of ordinary skill in the art will also understand that the gear structures disclosed above may be combined in any number in series or in parallel in the torque multiplier to increase the torque multiplication range beyond the actual range, or to increase the load capacity as needed.

[0077] Reference will now be made to Figures 1-21 provide more details regarding the operation of the torque multiplier, the gear structure, and other components.

[0078] Functional Overview

[0079] In torque multipliers (such as torque multipliers 100, 300, 1700, and 2300), a high-speed input shaft (such as shafts 101, 301, 801, 901, 1001, 1101, 1301, 1501, 1701, and 2102) drives an eccentric bearing (such as eccentric bearings 309 and 809) or an elliptical bearing (such as elliptical bearing 909). The outer race of the bearing (such as outer races 310, 810, 910, 1010, and 1110) contacts a plurality of rings (such as rolling rings 307, 807, 907, 1007, 1107, 1117, 1307, 1507, and 2007). Each ring is constrained on a pin (such as pin structures 308, 808, 908, 1008, 1108, 1118, 1308, 1508, and 2008) attached to a low-speed output shaft (such as shafts 102, 302, and 1702) or a housing (such as housings 103, 303, and 1703). These rings also contact a series of teeth (such as toothed rings 306, 806, 906, 1006, 1106, 1116, 1806, 1816, 2006) attached to the housing (or output shaft). The number of rings and pins is equal, but the number of teeth differs from the number of rings by at least one. Typically, there is one eccentric bearing and two elliptical bearings, but there could be three or more. Instead of an eccentric bearing or an elliptical bearing, other non-circular shapes can be used for the bearing, such as a three-lobed bearing.

[0080] The nature of the contact between the components reduces the relative sliding speed at each contact at the simultaneous pure rolling points at the toothed ring and the ring-pin interface. If the eccentric bearing is allowed to rotate freely, it also reduces the average sliding speed between the outer race and the ring. This no-slip point can be designed to coincide with the maximum force point, greatly reducing system friction.

[0081] Due to the mass of the parts moving with the eccentric axis, a basic eccentric bearing implementation may be unbalanced. In these cases, it is advantageous to balance the system by adding counterweights or using two sets of axially stacked component groups (as discussed in more detail below), with the eccentric positions offset by 180 degrees to eliminate radial imbalance. Stacking two, three, or four component groups can be used to further balance the forces and inertia of the system.

[0082] The system can be divided into three main functional groups: the high-speed eccentric shaft / wave generator, the pin structure anti-rotation mechanism, and the toothed ring.

[0083] High-speed eccentric shaft / wave generator

[0084] The eccentric motion of the rolling ring can be generated in a variety of ways. The simplest method is to directly drive the rolling ring using a crankshaft with eccentric bearings (such as shafts 301 and 1701). Another implementation uses a deformed roller bearing assembly (such as bearings 309, 809, and 909) to generate two or more eccentric cycles each time the high-speed shaft rotates. In an alternative configuration, the eccentric motion can be generated by a series of rolling elements of different sizes (such as rolling element 1012), thereby generating one, two, or more eccentric cycles each time the rolling element group rotates. This implementation achieves two-stage reduction, where the first stage is actually a planetary eccentric drive based on traction, and the second stage is a rolling ring, pin, and tooth system. The first stage of traction can drive either a circular bearing race on the eccentric axis or a flexible elliptical two-tooth bearing, or a similar shape with three or more teeth. Compared with the implementation where the first stage is a conventional crankshaft and bearing, this implementation provides additional transmission ratio variation at a very low cost in terms of efficiency, mass, or volume.

[0085] In the traction planetary implementation (such as gear structures 805 and 1005), the high-speed shaft is a cylindrical roller at the center of the device, which acts as a "sun" roller in contact with multiple rollers. These "planetary" rollers also contact the outer race, which acts as an annulus in the planetary system. The planetary rollers are of different sizes to allow the annulus and the orbital disk to orbit on an eccentric path without losing contact. The first stage of this mechanism provides an initial reduction from 2.1:1 to 14:1 depending on the size of the sun and the ring. A typical ratio for the first stage is 3:1.

[0086] The above eccentric traction planetary system is a convenient way to generate the eccentric motion of the orbital plate because it increases the range of possible amplification ratios without significantly increasing the system inertia or complexity. The disadvantage of a traction-based system is that due to the small amount of slip that occurs, the precise torque ratio may change during operation. In some applications, this is problematic.

[0087] Anti-rotation mechanism

[0088] The rolling ring array must be prevented from rotating relative to the low-speed output or a fixed reference frame while still allowing the circular motion caused by the crankshaft movement. The disclosed invention has a unique pure-rolling anti-rotation device (such as pin structures 308, 808, 908, 1008, 1108, 1118, 1308, 1508, and 2008).

[0089] The anti-rotation mechanism is used in conjunction with a series of fixed pins, each with a diameter smaller than the inner diameter of the rolling ring and approximately equal to the diameter of the crankshaft eccentricity or the amplitude of the elliptical flexible bearing race. When the eccentric bearing motion sequentially loads this array of pins and rings, a torque will be generated between the pins and the toothed ring.

[0090] Traditional implementations use a series of fixed pins and a series of matching holes in the orbiting cycloidal disk to prevent rotation. Unwanted friction is caused by the contact between the pins and the cycloidal disk, and additional measures are typically required to reduce the friction. These traditional implementations are often a source of significant friction losses and can lead to non-linear torque fluctuations.

[0091] The disclosed mechanism has advantages due to its simplicity, low manufacturing cost, high torque capacity, compact form factor, and reduced friction losses. Compared to traditional anti-rotation mechanisms, a nearly pure rolling motion also allows for a very smooth and linear torque output.

[0092] Cam ring

[0093] In the described implementations, based on the cycloidal curve, the cam ring (such as cam rings 306, 806, 906, 1006, 1106, 1116, 1806, 1816, 2006) has a plurality of similar cams. In a typical configuration, the track plate has 4 to 400 cams. In the illustrated implementations, the number of cams is one or two more or less than the number of rolling rings, and each rolling ring has a torque pin. This rule can vary, but doing so is generally disadvantageous. To make the device work properly, it is crucial that the number of cams and rolling rings differ by at least one.

[0094] The cycloidal-based curve is superior to other curve forms because the rolling rings can maintain their respective spacing and relative positions, which means they can be supported by a simple rigid cage. The cycloidal curve parameters are chosen in such a way as to achieve a nearly pure rolling motion between the various components, maximizing efficiency and torque transmission capacity. (These values can be optimized for different variables according to the requirements of the application).

[0095] The offset pure cycloidal profile is effective, but the cam profile can be strategically modified to allow lubricated running clearance, increase manufacturing difficulty, reduce the load in the sliding area, control the clearance, or reduce the load end effect. Alternative configurations can reverse the structure, placing the rolling rings outside the cam ring, in which case the cams will essentially become epicycloids rather than hypocycloids, but the same principle applies. Other disk shapes can also be used instead of cams. Non-cycloidal cam profiles can also be used to reduce rolling friction, increase load capacity, or improve manufacturability.

[0096] Cage

[0097] In some implementations, preferably the positions of the rolling rings relative to each other and relative to the eccentric axis are controlled. Simple cages (such as cages 1201 and 1401) can be used to prevent the rolling rings from moving from their desired positions during operation.

[0098] Figure 22 Depicts method 2200, which is a method of operating torque multiplier 100, 300, 1700, or 2300 using any of the above embodiments. Step 2201 includes receiving a first torque through a first shaft. Step 2102 includes amplifying the first torque through a gear structure coupled to the first shaft and the second shaft to generate a second torque provided by the second shaft, wherein the amplification includes rotating a bearing in response to the first torque, rotating a plurality of rolling rings around a pin in response to the rotation of the bearing, and rotating a toothed ring in response to the rotation of the plurality of rolling rings. Optionally, the amplification in step 2202 further includes preventing the movement of the rolling rings through a pin structure, or the amplification in step 2202 further includes rotating a pin structure that includes pins located in the plurality of rolling rings, and wherein the pin structure is fixed to the second shaft to rotate the second shaft to provide the second torque.

[0099] Figure 23 Depicts system 2300 that includes and utilizes torque multiplier 2301, wherein torque multiplier 2301 can be any of the above torque multipliers, such as torque multipliers 100, 300, 1700, and 2300. System 2300 can be any system that requires a torque multiplier to increase or decrease the torque between an input shaft and an output shaft. System 2300 can be any of the following examples:

[0100] · Aerospace and defense (CPC classifications B64C, B64D, B64G, F41G), including but not limited to:

[0101] o Main propulsion transmission of an aircraft

[0102] o Tail rotor drive of a helicopter

[0103] o Actuator of a drone propulsion system

[0104] o Drivetrain of a defense armored vehicle

[0105] o Actuator of an aircraft control surface

[0106] o Satellite solar panel drive

[0107] o Gear system of a space exploration rover

[0108] o Drilling and manipulation mechanisms for space applications

[0109] · Automotive and transportation (CPC classifications B60K, B60W, B62D), including but not limited to:

[0110] o Drivetrain of electric and hybrid electric vehicles

[0111] o Transmission of a hybrid system of turbocharging and supercharging for an internal combustion engine

[0112] o Actuators of power steering systems

[0113] o Drivetrains of electric bicycles and personal mobility devices

[0114] · Marine and offshore technology (CPC classification B63B, B63H, E21B), including but not limited to:

[0115] o Propulsion transmissions of ships

[0116] o Drive systems of marine actuators

[0117] o Gear reducers of offshore drilling equipment

[0118] · Construction and heavy machinery (CPC classification E02F, B66C, E21C), including but not limited to:

[0119] o Drive systems of excavators and bulldozers

[0120] o Transmissions of concrete pump trucks

[0121] o Rotating systems of tunnel boring machines

[0122] o Electrification of booms and jib actuators in earthmoving equipment

[0123] · Agriculture and forestry (CPC classification A01B, A01D, A01G), including but not limited to:

[0124] o Reduction devices of tractors

[0125] o Drivetrains of combine harvesters

[0126] o Actuators of irrigation systems

[0127] o Drivetrains of forestry equipment

[0128] · Energy and power generation (CPC classification F03D, Y02E, H02S), including but not limited to:

[0129] o Transmissions of wind turbines

[0130] o Drives of hydroelectric generator speed controllers

[0131] o Actuators of solar tracking systems

[0132] · Industrial and manufacturing automation (CPC classification B25J, B23Q, H01L), including but not limited to:

[0133] o Actuators of conveyor belt systems

[0134] o Transmissions of robotic arms and manipulators

[0135] o Drive systems for Automated Guided Vehicles (AGVs)

[0136] o Actuators for CNC and semiconductor manufacturing equipment

[0137] · Consumer goods and appliances (CPC classifications A47L, B25F, A63H), including but not limited to:

[0138] o Drivetrains for automated household appliances

[0139] o Gear systems for power tools

[0140] o Actuators for toys and video game devices

[0141] · Medical devices and healthcare (CPC classifications A61B, A61F, A61H), including but not limited to:

[0142] o Gear systems for surgical and diagnostic tools

[0143] o Drive mechanisms for medical equipment

[0144] o Actuation systems for advanced prosthetics

[0145] · Entertainment and fitness (CPC classifications A63G, A63B, H05B), including but not limited to:

[0146] o Drive systems for theme park rides

[0147] o Mechanisms for movie special effects

[0148] o Drivetrains for exercise and sports training equipment

[0149] · Logistics and material handling (CPC classifications B65G, B66F, B25J), including but not limited to:

[0150] o Drivetrains for warehouse robots

[0151] o Actuators for sorting systems and pallet stackers

[0152] o Transmissions for forklifts and logistics vehicles

[0153] · Public infrastructure and safety (CPC classifications E04H, A62B, B66B), including but not limited to:

[0154] o Transmissions for elevators and escalators

[0155] o Winch systems for emergency rescue

[0156] o Actuators for fire and rescue robots

[0157] o Radar positioning drives (CPC classifications G01S, G01C)

[0158] · Science and Exploration (CPC classifications GOIN, G01J, B64G), including but not limited to:

[0159] o Drives for laboratory centrifuges

[0160] o Actuation systems for telescopes and astronomical instruments

[0161] Materials

[0162] The transmission mechanisms disclosed herein are designed with versatility in mind, accommodating a range of materials to meet the specific requirements of applications, including but not limited to: high-strength alloys, corrosion-resistant stainless steels, titanium with high strength-to-weight ratios and low moduli, aluminum for lightweight applications, brass for machinability, thermoplastics for quiet operation, composites with customized thermal and structural properties, and advanced ceramics for high-wear environments. The material selection aims to optimize the performance, durability, and efficiency of the gears in their respective applications, whether it is high load capacity, precision operation, or environmental resilience. Additionally, the use of cutting-edge materials such as metal matrix composites and self-lubricating polymers is expected to adapt to future developments in materials science, thus ensuring that the transmission mechanisms remain at the forefront of advancements in power transmission technology.

[0163] Key Improvements

[0164] The disclosed improvements listed below all contribute to enhancing the energy efficiency and performance of the torque multiplication device:

[0165] · Rolling contact between the rolling ring and the optimized convex gear profile (reducing sliding friction at the convex teeth).

[0166] · Rolling contact low-friction anti-rotation mechanism (eliminating sliding friction on the output pin).

[0167] · Combined eccentric bearing and planetary reducer (increasing the torque ratio without significantly increasing friction or complexity).

[0168] · The combination of near-pure rolling contact in the convex tooth-ring-pin interface and the compliance of the ring, through preloading the interface, can significantly reduce or completely eliminate clearance. This is not practical in traditional torque multipliers because the resulting friction would be too high.

[0169] Advantages over Existing Devices

[0170] The advantages of the embodiments described herein over prior art devices include the following:

[0171] · Reduced cost and manufacturing complexity.

[0172] · Relatively high efficiency, with a power transmission efficiency between 70% and 100%.

[0173] · The large hollow hole facilitates cable routing and packaging design.

[0174] · Due to the load distribution between the convex teeth, the torque density is very high.

[0175] · Due to the rolling contact and optimized geometry, it runs smoothly and quietly, allowing continuous contact between the rolling ring, pins and convex teeth.

[0176] · Reduce the system inertia.

[0177] · The ratio of speed reduction or torque multiplication is one of the decisive features of the device. The application is suitable for devices usually in the transmission ratio range of 7:1 to 400:1, but the gear structures can be combined in series in the same housing to produce torque ratios several orders of magnitude higher or lower.

Claims

1. A torque multiplier, comprising: A first shaft for providing a first torque; A second shaft for providing a second torque; And A gear structure coupled to the first shaft and the second shaft to amplify the first torque to generate the second torque, the gear structure comprising: A toothed ring; A plurality of rolling rings in contact with the toothed ring; A pin structure including a plurality of pins, each of the pins being located within one of the rolling rings; and A bearing in contact with the plurality of rolling rings.

2. The torque multiplier according to claim 1, wherein, The bearing is eccentric.

3. The torque multiplier according to claim 1, wherein The bearing is elliptical.

4. The torque multiplier according to claim 1, wherein The bearing further includes a first race in contact with the plurality of rolling rings.

5. The torque multiplier according to claim 4, wherein, The bearing further includes a second race and a plurality of rolling elements located between the first race and the second race.

6. The torque multiplier according to claim 1, wherein, The toothed ring includes an inner circumference that includes modified epicycloid teeth.

7. The torque multiplier according to claim 1, further comprising a cage for holding the plurality of rolling rings.

8. The torque multiplier according to claim 7, wherein, The cage is a single piece.

9. The torque multiplier according to claim 7, wherein, The cage is a two-piece.

10. A torque multiplier, comprising: A first shaft for providing a first torque; A second shaft for providing a second torque; A first gear structure coupled to the first shaft to receive the first torque, the first gear structure comprising: A first toothed ring; A first group of a plurality of rolling rings in contact with the first toothed ring; A first pin structure including a plurality of pins, each of the pins being located within one of the first group of a plurality of rolling rings; and A first bearing in contact with the plurality of rolling rings; and A second gear structure coupled to the first gear structure and the second shaft to amplify the first torque to generate the second torque, the second gear structure comprising: A second toothed ring; A second group of a plurality of rolling rings in contact with the second toothed ring; A second pin structure including a plurality of pins, each of the pins being located within one of the second group of a plurality of rolling rings; and A second bearing in contact with the plurality of rolling rings.

11. The torque multiplier according to claim 10, wherein, The first toothed ring includes an inner circumference that includes modified epicycloid teeth.

12. The torque multiplier according to claim 11, wherein, The second toothed ring includes an inner circumference that includes modified epicycloid teeth.

13. A method of amplifying torque, comprising: Receiving a first torque through a first shaft; And Amplifying the first torque through a gear structure coupled to the first shaft and a second shaft to generate a second torque provided by the second shaft, wherein the amplifying includes rotating a bearing in response to the first torque, causing a plurality of rolling rings to rotate around pins in response to the rotation of the bearing, and rotating a toothed ring in response to the rotation of the plurality of rolling rings.

14. The method according to claim 13, wherein, The toothed ring is fixed to the second shaft to rotate the second shaft to provide the second torque.

15. The method according to claim 14, wherein, The amplifying further includes preventing the rolling rings from moving through a pin structure.

16. The method according to claim 14, wherein, The amplifying further includes rotating a pin structure that includes pins located within the plurality of rolling rings, and wherein the pin structure is fixed to the second shaft to rotate the second shaft to provide the second torque.

17. The method according to claim 13, wherein, The bearing is eccentric.

18. The method according to claim 13, wherein, The bearing is elliptical.

19. The method according to claim 13, wherein, The bearing includes a first race in contact with the plurality of rolling rings.

20. The method according to claim 19, wherein, The bearing further includes a second raceway and a plurality of rolling elements located between the first raceway and the second raceway.

21. The method according to claim 20, wherein, The toothed ring includes an inner circumference which includes modified cycloidal teeth.

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