阅读说明：本技术 扭矩放大器 (Torque amplifier ) 是由 詹姆斯·克拉森 于 2018-06-18 设计创作，主要内容包括：本发明公开了一种扭矩传递装置,该扭矩传递装置具有环形齿轮和内行星齿轮组和外行星齿轮组,该行星齿轮组可能不绕轨道而是相对于外壳在固定位置旋转。该齿轮组中的一个可包括复合齿轮。也可能有连接到行星齿轮组的太阳齿轮。该太阳齿轮可以是输入,而环形齿轮可以是减速齿轮系统的输出,以充当扭矩放大器。齿轮可为锥形,并且也可对齿轮组中的一个施加轴向力,以紧固锥形齿轮之间的啮合。齿轮组中的一个(例如,向其施加轴向力的齿轮组)可以是浮动的。(The invention discloses torque transmitting devices having a ring gear and inner and outer planetary gear sets that may not orbit but rotate in a fixed position relative to a housing of the gear sets may include compound gears, there may also be a sun gear connected to the planetary gear sets, the sun gear may be the input and the ring gear may be the output of a reduction gear system to act as a torque amplifier, the gears may be tapered and may also apply an axial force to of the gear sets to tighten the mesh between the tapered gears of the gear sets (e.g., the gear set to which the axial force is applied) may be floating.)

An torque transmitting device, comprising:

a housing;

a ring gear having a tapered ring gear tooth portion, the ring gear mounted for rotation relative to the housing;

a plurality of th planet gears having a second tapered tooth portion arranged to mesh with the tapered ring gear tooth portion, the plurality of th planet gears having a th tapered tooth portion arranged to mesh with the second tapered tooth portion, the plurality of second planet gears arranged within the ring gear to mesh with the ring gear, and each of the plurality of planet gears arranged to mesh with two of the plurality of second planet gears, and

a biasing element to bias the plurality of th planet gears or the plurality of second planet gears to tighten the mesh between the th tapered tooth portion and the second tapered tooth portion.

2. The torque transmitting device according to claim 1, wherein the biasing element is for biasing the plurality of second planet gears.

3. The torque transmitting device according to claim 1 or claim 2, wherein the plurality of second planet gears are floating gears.

4. The torque transmitting device of any of claims 1-3, wherein the tapered ring gear tooth, the tapered tooth, and the second tapered tooth are mirror helical teeth.

5. The torque transmitting device of , wherein the plurality of planetary gears are compound gears including a th simple gear having the th tapered tooth portion and a second simple gear fixedly connected to the th simple gear for rotation with the th simple gear , and further including a sun gear arranged to mesh with the second simple gear.

6. The torque transmitting device according to claim 5, wherein the second simple gear is larger than the th simple gear.

7. The torque transmitting device of claim 5 or claim 6, wherein the plurality of th planet gears are axially movable relative to the housing, and the second simple gear has a third conical tooth portion, and the sun gear has a conical sun gear tooth portion, the third conical tooth portion being arranged to mesh with the conical sun gear tooth portion.

8. The torque transmitting device of claim 7, wherein the tapered sun gear tooth and the third tapered tooth are mirror helical teeth.

9. The torque transmitting device of any of claims 1-8, wherein the biasing element includes a permanent magnet.

10. The torque transfer device of any of claims 1-8, wherein the biasing element comprises an electromagnet.

11. The torque transfer device of any of claims 1-8, wherein the biasing element comprises a permanent magnet and an electromagnet.

12. The torque transmitting device as claimed in any of claims 1-8 wherein the biasing element comprises a spring.

13. The torque transmitting device of any one of claims 1-12, , further comprising a brake for stopping the torque transmitting device in the event of a loss of electrical power.

14. The torque transmitting device according to claim 13, wherein the brake is arranged to grip a cylindrical surface connected to at least of the plurality of th planet gears.

15, a brake, comprising:

a belt having a th end and a second end, the belt extending circumferentially around a surface of a rotating object, the belt being movable between a clamped position contacting the surface of the rotating object and an energized position;

th and second permanent magnets, the th permanent magnet being attached to the th end of the band, the second permanent magnet being attached to the second end of the band, the th and second permanent magnets being arranged to attract each other in the clamped position such that the band clamps the cylindrical surface;

the th and second permanent magnets being biased away from the energized position to move the band to the clamped position, and

or more electromagnets, said or more electromagnets arranged to be supplied with current to attract said th and said second permanent magnets to hold said strip in said energized position against said bias when current is supplied to said electromagnets.

16. The brake of claim 15 wherein said or more electromagnets are configured for being energized with a current to move said band from said clamped position to said energized position and for being energized with a second current to hold said band in said energized position, said second current being lower than said current.

17. A brake according to claim 15 or claim 16 in which the th and second permanent magnets are biased away from the energised position by the magnetic attraction of the th and second permanent magnets.

18, combination brake comprising a plurality of brakes according to any of claims 15-17 arranged in a circular array, the band of each brake of the plurality of brakes being connected to successive brakes of the plurality of brakes by a flexible bridge.

19. The brake of claim 18 wherein said or more electromagnets of each of said plurality of brakes comprise two electromagnets, each of said two electromagnets being shared by a respective adjacent brake of said plurality of brakes.

20. The torque transmitting device according to claim 13 or claim 14, wherein the brake is a brake according to any of claims 15-17, or a combination brake according to claim 18 or claim 19.

Technical Field

A gear box.

Background

Gearboxes are commonly used to increase the torque in the system above that which can be provided by the motor. These gearboxes typically introduce backlash and significant inertia into the system. It is desirable to minimize the added inertia and eliminate backlash while still providing high output torque.

Disclosure of Invention

The invention provides a torque transmitting device having a housing and a ring gear with a tapered ring gear tooth, the ring gear mounted for rotation relative to the housing, the torque transmitting device further having a plurality of planet gears and a plurality of second planet gears, the plurality of second planet gears having a second tapered tooth arranged to mesh with the tapered ring gear tooth, the plurality of planet gears having a tapered tooth arranged to mesh with the second tapered tooth, the plurality of second planet gears arranged to mesh with the ring gear within the ring gear, and every of the plurality of planet gears arranged to mesh with two of the plurality of second planet gears.

In various embodiments, any one or more of may be included that may be any of a biasing element may be used to bias a plurality of second planet gears, the plurality of second planet gears may be floating gears, the tapered ring gear teeth, the tapered teeth, and the second tapered teeth may be mirror image helical teeth, the plurality of 0 planet gears may be compound gears, the compound gears include a simple gear having a th tapered tooth and a second simple gear fixedly connected to a simple gear for rotation with a rd simple gear , and there may be a sun gear arranged to mesh with the second simple gear.

A brake including a band having a end and a second end, the band extending circumferentially around a surface of a rotating object, the band being movable between a clamped position contacting the surface of the rotating object and an energized position, a th permanent magnet attached to the th end of the band and a second permanent magnet attached to the second end of the band, the th and second permanent magnets arranged to attract each other in the clamped position to cause the band to clamp the cylindrical surface, a th and second permanent magnets biased away from the energized position to move the band to the clamped position, but supplying current to or more electromagnets to attract the th and second permanent magnets to hold the band in the energized position against the bias when current is supplied to the electromagnets is also provided.

In various embodiments, any or more of or more electromagnets may be configured for energizing with a th current to move the band from the clamped position to the energized position and for energizing with a second current to hold the band in the energized position, the second current being lower than the th current the th and second permanent magnets may be biased away from the energized position by the magnetic attraction of the th and second permanent magnets.

combination brakes including a plurality of brakes as described above, the plurality of brakes arranged in a circular array, the band of each brake of the plurality of brakes connected to successive brakes of the plurality of brakes by a flexible bridge, or more electromagnets of each of the plurality of brakes may include two electromagnets, each of the two electromagnets shared by a respective adjacent brake of the plurality of brakes.

These and other aspects of the apparatus and method are set out in the claims.

Drawings

Embodiments will now be described, by way of example, with reference to the accompanying drawings, wherein like reference numerals represent like elements, and in which:

FIG. 1 is a plan view of an exemplary torque amplifier.

Fig. 2 is a perspective view of the torque amplifier of fig. 1.

FIG. 3 is a close-up view showing the forces and mesh points on the floating gear of the torque amplifier of FIGS. 1 and 2.

Fig. 4 is a schematic diagram showing a spring attached to a bearing as an alternative means of applying force to the planet gears.

Fig. 5 is a close-up perspective view of an exemplary tapered tooth shape.

Fig. 6 is a cross-section of the tooth of fig. 5 at the narrow end of the tooth.

Fig. 7 is a cross-section of the tooth of fig. 5 in a middle portion of the tooth.

Fig. 8 is a cross-section of the tooth of fig. 5 at the wide end of the tooth.

Fig. 9 is a side view of a gear including a tooth having a taper angle.

FIG. 10 is a perspective view of an exemplary gear having a tapered tooth portion.

Fig. 11 is an axial view of the gear of fig. 10.

Fig. 12 is a schematic diagram showing various diameters of the gear of fig. 10.

Fig. 13 is a schematic diagram showing the diameter and tooth side arc of the gear of fig. 10 at the th end of the tooth.

Fig. 14 is a schematic view showing the diameter of the gear of fig. 10 at the middle portion of the tooth portion and the tooth portion side arc.

Fig. 15 is a schematic view showing the diameter of the gear of fig. 10 at the second end of the tooth portion and the tooth portion side arc.

Fig. 16 is a side cross-sectional view of an actuator having an electric motor and a torque amplifier as shown in fig. 1-3.

FIG. 17 is a top cross-sectional view of the actuator of FIG. 16, also including a detent, wherein the detent is in a clamped position.

Fig. 18 is a perspective view of the actuator of fig. 17.

FIG. 19 is a top cross-sectional view of the actuator of FIG. 17 with the actuator in the energized position.

Fig. 20 is a perspective view of the actuator of fig. 19.

FIG. 21 is a perspective view of a torque amplifier with magnets in the outer planetary gear.

FIG. 22 is a cut-away perspective view of a torque amplifier with springs attached to the planet gears.

Detailed Description

Insubstantial modifications of the embodiments described herein are possible without departing from what is intended to be covered by the claims.

A non-limiting exemplary embodiment of torque amplifier 10 is shown in plan view in FIG. 1 and in perspective view in FIG. 2. the torque amplifier 10 in this embodiment is a gear system having a sun gear 12, a -th planetary gear array, a second planetary gear 18 array, and a ring gear 20, the -th planetary gear here being a compound gear including a larger gear 14 and a smaller gear 16 in mesh with sun gear 12, the second planetary gear 18 being in mesh with a smaller gear 16, the ring gear being in mesh with the second planetary gear 18 array. here, the smaller gear 16 and the larger gear 14 are fixed to form a compound -th planetary gear, but the smaller gear 16 may be otherwise connected to the larger gear 14 to rotate with a -th larger gear 14 . here, sun gear 12 is an input fixed to the rotor of the motor and ring gear 20 is an output.

The term "planet" in this document does not mean that the planet rotates around an orbit; rather, it describes positioning, such as within the ring gear, around the sun gear, or contacting other planetary gear pairs.

In the embodiment shown, there are four th planet gears, and four second planet gears 18, with each th planet gear comprising a larger gear 14 and a smaller gear 16, but other numbers of gears can be used in embodiments torque multiplication is achieved with the sun gear 12 being smaller than the ring gear 20 and the smaller gear 16 being smaller than the larger gear 14 of the th planet gear the smaller diameter gear 16 is fixed to the top of the larger gear 14 which provides additional gear reduction as the smaller gear 16 drives the second array of planet gears 18 the smaller gear 16 can also be, for example, below the th planet gear 14 then the second array of planet gears 18 drives the outer ring gear 20 (output) the set of second planet gears 18 is unique in that each gear floats in place and takes up any backlash with the applied downward magnetic force, as described below.

FIG. 3 illustrates a mechanism that allows the second planet gears 18 to float, as shown in FIG. 3, each floating gear 18 has three gear mesh contacts to position it in the XY direction, two th gear mesh positions, identified by arrow 28 at , where the floating gear 18 meshes with two smaller diameter gears 16 in the planetary stage, and mesh positions, identified by arrow 30, where the floating gear 18 meshes with the ring gear 20.

By using bearings on the th planet set that allow a small amount of axial displacement, but ensure that the gears do not rotate about a horizontal axis out of plane, the applied downward magnetic force can be transferred from the floating second planet 18 to the th planet and then to the sun gear 12 this ensures that with the proper downward force on the floating gear, backlash in any gear joints is eliminated the area of gear engagement with the bearing/bushing on the th planet shaft ensures that any torque created by the offset axial force does not cause the gears to rotate out of plane and cause other problems with gear tooth meshing this can be accomplished on the th planet gear through pairs of roller bearings or another type of bearing (such as a needle bearing that allows some axial movement).

The tapered junction between the two stage gears 14 and 16 forming the th planet and the floating gear forming the second planet 18, and the tapered junction between the output ring 20 and the floating gear provide XY positioning when an axial preload is applied to the floating gear.

The axial preload of the floating gear may be provided by a variety of means, including but not limited to: attracting the steel floating gear or the permanent magnet in the housing of the permanent magnet in the floating gear; an electromagnet in the housing that attracts a steel floating gear or permanent magnet in the floating gear; or a spring preload that preferably acts against the bearings in the floating gear and is compliant enough to allow axial displacement and XY displacement of the floating gear when the floating gear finds the best fit position in the XY direction.

In the embodiment shown in fig. 3, the magnet 32 (which may be a permanent magnet or an electromagnet) attracts the steel second planetary gear 18 which provides an axial force indicated by large arrow 34.

A permanent or electromagnet 32 between the housing 22 and each conical floating second planet gear 18 can provide a preload to the system to take up any backlash. Alternatively, a force may be applied mechanically to the top or bottom of the gear 18 to provide a downward force.

The second planet gears 18 may also have magnets 56 as shown in FIG. 21 so that the second planet gears 18 may be made of a non-magnetic material and still receive axial force from the permanent or electromagnet 32. in FIG. 21, a rotor 42 and a housing 22 are shown, according to an embodiment, the housing member shown may be a stator, but electromagnetic elements for the rotor and stator to act as an electric motor are not shown. in embodiments, a lower stator, not shown in this figure, may also be added.

FIG. 4 shows examples of mechanically applied forces, in this illustrative example the second planet gear 18 is located on the shaft 36 rather than being free floating, the components in this figure are not necessarily drawn to scale, the spring 38 is connected to the housing and the interior of the bearing 40 slidably supported on the shaft, the interior of the bearing 40 rotatably supports the exterior of the bearing 40 on which the second planet gear is mounted, the spring 38 pushes or pulls the bearing to apply an axial force to the second planet gear 18. in this illustrative example, the ring gear 20 is shown, but the th planet gear and smaller gears are omitted, another example is shown in FIG. 22. in this example, the spring 38 is connected to the upper portion 62 of the housing 22, which upper portion 62 is connected to the remainder of the housing 22 in this embodiment by the top cover 24. the pivotable connection 64 connects the spring 38 to the floating planet gear 18. the spring may also be connected directly from the housing to the floating planet gear from below, and may be pushed or pulled.

As shown in the illustrative example of FIG. 4, the second planet gears need not be floating, they may also be located on a shaft 36 mounted on the housing, so long as they are axially displaceable on the shaft.

In embodiments, the gears of the compound gear may be axially movable, but rotationally fixed relative to each other, and connected, for example, by springs.

Thus, low gear friction can be achieved at low torque conditions to achieve low rebound friction and low wear, while axial preload can be increased at increased torque conditions to maintain zero backlash characteristics at high torque levels, where the axial reaction force on the gear will be higher.

The floating gear is restrained in three places by the th stage planet gear and ring gear so that no additional support is required.

Gear tooth profile

Involute tooth profiles may be used to allow for small deviations of from center distance without adversely affecting gear mesh.

The mirror-image helical tooth form may use a mirror-image helical gear shape to achieve tooth taper, although other methods may be used, the mirror-image helical design allows cases of each tooth to be cut by helical operations (such as by hobbing with a gear tooth hob or a form cutter), while another cases of teeth are cut with the opposite helical operation, resulting in a smoothly meshing tooth while allowing the taper to occupy any gap in either rotational direction fig. 5-8 show examples of mirror-image helical tooth forms.

FIG. 5 shows a single exemplary tooth 50 on the floating gear 18, other teeth will be present, but not shown, corresponding tooth profiles may be used on each other gear, only the meshed gears need to have corresponding tooth profiles, thus it is also possible for the sun gear 12 and the th planet gears 14 to use non-corresponding tooth profiles that are different from the smaller gears 16, the second planet gears 18, and the ring gear 20. portions 6-6, 7-7, and 8-8 show planes corresponding to the views of FIGS. 6, 7, and 8, respectively. FIG. 6 shows a cross-section of the front of the tooth 50. FIG. 7 shows a cross-section of the middle of the tooth 50. FIG. 8 shows a cross-section of the back of the tooth 50. the tooth and preload work to eliminate backlash.

In another embodiment of the tooth profile, the crests and roots of the sun, planet, and ring gears are adjusted so that a tapered tooth effect is achieved without changing the aspect ratio, details of this are described below and shown in FIGS. 9-15. in this embodiment, instances of the gears can extend the tips of the gears farther, as shown in FIG. 9, the change in extension of the gear tips over the thickness is a taper angle.

Fig. 10-15 show more details of the design of the tapered gear tooth profile with this taper angle the design of the gear shown may be used with the torque multiplier shown in fig. 1-3 or in other applications.

As shown in fig. 10 and 11, there is a gear 100 having a plurality of teeth 102. The teeth are tapered such that a trailing end 106 of each tooth extends radially outward from the central axis of the gear farther than a leading end 104 of each tooth. Similarly, the gaps 108 between each tooth are tapered. The rear end 110 of each gap extends radially outward from the central axis of the gear farther than the front end 112 of each gap. The tooth crest of each tooth, defined by its sides 114 and 116, is displaced according to the cone, as shown in more detail in fig. 13 to 15.

Fig. 12 shows an exemplary sketch of a positive tip shift profile and the notable diameters of the marks, including tip circle, pitch circle, base circle, and root (root circle) diameters.

Fig. 13-15 show the gear tooth profile at three points along the length of the tooth fig. 13 shows the shape of the tooth tip through the back 106 of each tooth defined by line a and line B fig. 14 shows the shape of the tooth tip through the middle 102 of each tooth defined by line a and line B fig. 15 shows the shape of the tooth tip through the front 104 of each tooth defined by line a and line B mid-plane is used to define the tooth profile in its standard configuration on any axial end of the gear, tooth tip displacement is done, shifting the gear tooth up or down, between these three planes there is linear interpolation of the gear teeth.

When combined with a second bevel gear, the same tip shift is used, and the positive shift faces of gears mesh when the positive shift faces contact the negative shift faces of another gears.

For every gears in the sun, planet, and ring gears, the changes in the addendum and dedendum due to the cone of the gear body result in a change in the tooth profile because different sections of the mathematical involute are used.

The bevel gear allows preloading by applying an axial load to the gear. This has the effect of eliminating backlash between the gears. In addition, it allows the gear to be more easily injection molded.

The taper angle of the body may be selected in conjunction with a material from which the gear is made so that the taper angle ensures the highest possible axial load, but remains outside the region considered to be self-locking.

The design can be customized by adjusting the gear diameter and number of teeth accordingly to provide the desired gear ratio and outer diameter.

The pitch diameter of each gear (in the case of a compound gear, the pitch diameter of each gear making up the compound gear) may be selected to remain constant over the respective thickness of the gear body. A pure mathematical involute may be used for the teeth on each gear to prevent backlash due to the tooth profile.

The tooth taper can be adjusted to match the axial deflection desired in the floating gear generally, a higher tooth taper angle results in less axial deflection of the floating gear for a given gear lash change.

Material

The magnetic material, such as steel or iron, may be used for the floating gear to respond to the magnetic field, thereby creating the downward magnetic force needed to preload the bevel gear and eliminate backlash.

Motor with a stator having a stator core

The motor may be, for example, an axial motor including a double-sided rotor 42, the double-sided rotor 42 having an upper stator 44 above the rotor and a lower stator 46 below the rotor, the stators 44 and 46 forming part of the housing 22. the double stator design minimizes the net magnetic force on the rotor.

Brake

For many applications (such as robotics), brakes are required on the actuators to prevent the device from rotating when the system loses power integrated brakes with redundancy and low power consumption are disclosed herein, such as for use with the reflected torque amplifier described above.

FIG. 17 is a top view of the actuator described above, FIG. 18 is a perspective view of the actuator described above, but including the brake shown in a clamped position, the th planet includes a portion 200 having a rotating friction surface 202, a band clamp 204 surrounds the cylindrical surface 202 of the portion 200 and acts as a brake when the actuator loses power, as shown in this clamped position in FIGS. 17 and 18, a permanent magnet 206 is secured to the split end of the band clamp and pulled to clamp the band clamp 204 around the cylindrical surface 202.

An electromagnet 208 having a coil 210 and a core 212 is shown in fig. 17 and 18, but will be described in connection with fig. 19 and 20.

Connecting the band clamp can simplify assembly and construction by converting all band clamps (e.g., three or four) into a single component.

Fig. 17 is a top view of the actuator as described above, and fig. 18 is a perspective view of the actuator as described above, but including the actuator shown in the energized position with the belt clamp held away from the portion 200.

To reduce power consumption, when the belt clamp 204 is disengaged and moved to the position shown in fig. 19 and 20, the attraction of the permanent magnet 206 to the steel core 212 of the electromagnet 208 is nearly but not enough to hold the belt clamp 204 open, the remaining force must be provided by the coil 210. the belt clamp 204 is biased at such that when power to the coil 210 of the electromagnet 208 is lost, the biasing force pulls the belt clamp away from the electromagnet to tighten the belt clamp around the portion 200 to prevent the rest of the gear and actuator from rotating.

The biasing force may be provided by attraction of a permanent magnet to an electromagnet or by other forces such as the spring force of a band clamp.

In this way, a very strong clamping force can be obtained when not energized, and when the brake is disengaged, it is necessary to use very little holding force from the electromagnet.

Preferably, there is an expandable portion, such as a flexible bridge 214, between the band clamps to allow the band clamps 204 to freely move outward when engaged and radially inward when disengaged. With the position of the electromagnet 208 sufficiently accurate, the band clamp may not require a rigid attachment point to the housing to provide a rigid braking effect.

When power is removed from the electromagnet 208, the belt clamp 205 snaps from the position shown in fig. 19 and 20 to the clamped position shown in fig. 17 and 18 when power is restored, in embodiments, a burst of power may be provided to the electromagnet 208 to pull the magnet 206 apart to the energized position shown in fig. 19 and 20.

While each magnet attached to the belt clamp may be attracted by a different electromagnet as shown, a single electromagnet in a horseshoe configuration may also be used to attract two magnets attached to a single belt clamp.

The indefinite articles "" and "" preceding a feature of a claim do not exclude the presence of more than features every of the various features described herein may be used in or more embodiments and, as described only herein, will not be construed as being essential to all embodiments defined by the claim.