Drive device

Abstract

To provide a speed reducer and driving device which allow for their shape to be reduced.SOLUTION: A speed reducer 11 includes a crank shaft 51 and a plurality of gears 41, 42 which change the speed of rotation input from a rotation device 12 and output it, a second case 22 accommodating the crank shaft 51 and the plurality of gears 41, 42 and having an internal tooth pin 26, and a heating part 70 provided in the second case 22 for heating the second case 22 or the inside of the second case 22.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to Drive This relates to operating devices. [Background technology]

[0002] Patent Document 1 discloses a reducer including an external gear, an internal gear with which the external gear internally meshes, a casing in which the internal gear is provided, and a carrier that rotates relative to the casing. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2016-109264 A Summary of the Invention [Problem to be solved by the invention]

[0004] Incidentally, it is considered that the speed reducer is used in various kinds of equipment, etc. However, in order to apply the speed reducer to various kinds of equipment, etc., it is required that the speed reducer is formed so as to be able to be accommodated in the space of the various kinds of equipment, etc. in which the transmission is installed.

[0005] The present invention can be applied to a variety of facilities and can be made compact. Drive A moving device is provided. [Means for solving the problem]

[0006] A reducer according to one embodiment of the present invention includes a group of gears that change the speed of rotation input from a rotating device and output the rotation, a case that houses the group of gears, and a heating section that is provided in the case and heats the case or the inside of the case.

[0007] Here, when using a speed reducer outdoors, the temperature often drops below freezing in some regions. When starting the speed reducer in such an environment, the lubricant inside the speed reducer, especially, solidifies, making it difficult to satisfy the performance of the speed reducer. For example, it is also conceivable that the speed reducer may become inoperable. For example, when the speed reducer is provided in a vehicle's steering device, conventionally, the heat of the engine has been used to avoid solidification of the lubricant. However, in recent years, vehicle electrification (motor drive) has advanced, and in the case of an electrified vehicle, it is difficult to raise the temperature of the lubricant by the heat of the engine.

[0008] Therefore, a heating part is provided (built in) in the case of the speed reducer. With such a configuration, the heating part provided in the case can raise the temperature of the lubricant inside the case, for example, even in a cold region, and lower the viscosity of the lubricant. As a result, for example, even when the speed reducer is provided in a vehicle with cold-region specifications, the speed reducer can be reliably started. Furthermore, by providing the heating part using the case of the speed reducer, there is no need to separately prepare a dedicated mounting member for providing the heating part, and the speed reducer can be miniaturized. As a result, the speed reducer can be mounted on various equipment, etc., and the range of applications can be expanded.

[0009] A speed reducer according to another aspect of the present invention includes a gear group that decelerates and outputs the rotation input from a rotating device, a case that houses the gear group, and a sleeve that protects a seal that seals the case and is provided on the case.

[0010] Here, when using the speed reducer outdoors, especially in a special environment such as in-vehicle use, external factors that have not had an impact conventionally, such as rain, high-pressure washing, ultraviolet rays, and flying stones, increase. For this reason, at present, there is no speed reducer that can guarantee outdoor use. By the way, for example, sleeves are generally used for cleaning robots, but with these shapes, it is difficult to prevent external factors such as rain, high-pressure washing, ultraviolet rays, and flying stones.

[0011] Therefore, the gap of the case was suitably closed with a sleeve. Thus, the oil seal can be well (reliably) covered with the sleeve. Thereby, the oil seal can be protected from external factors such as rain, high-pressure washing, ultraviolet rays, and flying stones by the sleeve. Also, the sleeve was provided on the case. Thereby, dedicated parts for attaching the sleeve can be made unnecessary, and the speed reducer can be miniaturized.

[0012] In the above configuration, the case may have internal teeth, and the gear group may include a crankshaft rotatably supported so that the axial direction of the case becomes the rotation axis direction, and a plurality of external tooth members having external teeth meshing with the internal teeth and eccentrically moving by the crankshaft.

[0013] A speed reducer according to another aspect of the present invention includes a case having internal teeth, a crankshaft rotatably supported inside the case in the radial direction so that the axial direction of the case becomes the rotation axis direction, and a plurality of external tooth members having external teeth meshing with the internal teeth and eccentrically moving by the crankshaft. The internal teeth have 80 to 120 teeth, and the crankshaft has an eccentricity of 1.3 mm or less.

[0014] Here, as requirements for the speed reducer provided in the steering device, it is necessary to be lightweight, miniaturized, and have high load resistance. The steering device assists with a rotating device such as a motor while the operation by the driver is also performed simultaneously. For this reason, it is required to perform steering without a sense of incongruity in the feeling and sensation (feeling) applied to the steering wheel. Furthermore, since a mechanism for eccentric oscillation is provided inside the speed reducer, it is necessary to cause a smooth eccentric oscillation motion.

[0015] Therefore, the number of teeth of the internal teeth was set to increase to 80 to 120. By increasing the number of teeth of the internal teeth, the internal teeth receiving the load from the external tooth members can be increased. Thereby, the speed reducer can be made small and still cope with high load resistance. In addition, the eccentricity of the crankshaft was set to 1.3 mm or less. By reducing the eccentricity of the crankshaft, the vibration amounts of the crankshaft and the external gear member can be suppressed to low levels. As a result, there is no discomfort for the operator, and the speed reducer can rotate smoothly.

[0016] A drive device according to another aspect of the present invention includes a rotating device, a gear train that changes the rotation input from the rotating device and outputs the changed rotation, and a case that houses the gear train, and the rotating device is attached to the case. The drive device includes a speed reducer, and one wall of the case to which the rotating device is attached is also used as one wall of the housing of the rotating device.

[0017] Here, generally, in a rotating mechanism (for example, a motor), the entire device main body (for example, a motor main body) is covered with a mechanism case. Therefore, when the rotating mechanism is attached to the speed reducer, the case of the speed reducer and the case of the rotating device are overlapped at the attached part. Further, for example, in order to attach the case of the rotating device to the case of the speed reducer with bolts or the like, it is necessary to form screw holes in the case of the speed reducer. For this reason, the plate thickness of the case of the speed reducer increases.

[0018] By the way, the drive shaft of the rotating device penetrates through the case of the rotating device and the case of the speed reducer and is disposed inside the speed reducer. Therefore, it is conceivable that the drive shaft of the rotating device becomes long and the inertia increases. For this reason, it is conceivable that the burden on the rotating device increases. In addition, since the case of the speed reducer and the case of the rotating device are overlapped, it becomes difficult to make the drive device flat (that is, miniaturize it).

[0019] Therefore, the case part of the speed reducer case facing the rotating device is also used as a part of the case of the rotating device. Therefore, a configuration can be adopted in which only the case part is interposed between the speed reducer and the rotating device. As a result, the drive shaft of the rotating device can be shortened and the inertia can be suppressed to a low level, so that the burden on the rotating device can be suppressed to a small level. In addition, the drive device can be made flat (that is, miniaturized).

[0020] In the above configuration, the case has internal teeth, and the gear group includes a crankshaft that is rotatably supported such that the axial direction of the case is the rotation axis direction, and a plurality of external tooth members that have external teeth meshing with the internal teeth and perform eccentric motion by the crankshaft. The rotating device may input a rotational force to the crankshaft.

[0021] A drive device according to another aspect of the present invention includes a rotating device, a speed reducer having a gear group that changes the rotation input from the rotating device and outputs it, and an operating mechanism that inputs an external rotational force to the gear group. The operating mechanism includes a detection unit that detects the rotation angle and torque when the rotational force is input to the gear group.

[0022] Here, in the steering device of a vehicle, in order to achieve automated driving and electrification, the installation of sensors for performing automatic steering and assist control is required. For this reason, sensors (for example, a detection unit that detects the rotation angle and torque) that can be installed in the in-vehicle space of current vehicles are necessary. Also, from the structure of current vehicles, for example, the crankshaft (rotation axis) of the speed reducer is arranged orthogonally to the operating shaft connected to the steering wheel. For this reason, for example, a bevel gear is provided on the operating shaft in the operating mechanism, and a detection unit is further provided on the operating shaft.

[0023] By configuring in this way, for example, sensors (for example, a detection unit that detects the rotation angle and torque) necessary for automatic steering and assist control can be installed in a small space of current vehicles, and orthogonal axis input from the operating shaft connected to the steering wheel becomes possible. Specifically, for example, by controlling the rotating device based on the rotation angle and torque detected by the detection unit, the speed reducer can be operated by the rotating device. Thereby, the operation of the driver can be assisted by the detection unit and the rotating device.

[0024] With the above configuration, the speed reducer includes a case having internal teeth, and the gear group includes a crankshaft rotatably supported such that the axial direction of the case becomes the rotation axis direction, and a plurality of external tooth members having external teeth meshing with the internal teeth and eccentrically moving by the crankshaft. The rotating device and the operating mechanism may input a rotational force to the crankshaft.

[0025] A drive device according to another aspect of the present invention includes a case having internal teeth, a crankshaft rotatably supported inside the case in a radial direction thereof such that the axial direction of the case becomes the rotation axis direction, a plurality of external tooth members having external teeth meshing with the internal teeth and eccentrically moving by the crankshaft, and an operating mechanism for inputting an external rotational force to the crankshaft. The operating mechanism includes a driven bevel gear for transmitting a rotational force to the crankshaft, and a drive bevel gear provided at a position orthogonal to the axis of the driven bevel gear and meshing with the driven bevel gear. The driven bevel gear is switchable between a first meshing position for changing the rotation direction of the driven bevel gear and a second meshing position.

[0026] Here, the steering device differs between right-hand drive and left-hand drive depending on the vehicle type and the country of use. For this reason, the steering device is designed differently depending on whether it is a right-hand drive or a left-hand drive. In order to accommodate both right-hand drive and left-hand drive, for example, the layout of mounting the operating mechanism in the vehicle is changed, or the screw direction of the built-in ball screw for steering is changed.

[0027] By configuring in this way, it is possible to reverse the rotation direction of the driven bevel gear with respect to the rotation of the drive bevel gear only by switching the driven bevel gear between the first meshing position and the second meshing position. That is, the rotation of the driven bevel gear can be changed without changing the design of any parts other than changing the mounting position of the driven bevel gear. In addition, the operating mechanism can be made smaller, and the drive device with a speed reducer can be miniaturized.

[0028] A drive device according to another aspect of the present invention includes a case having internal teeth, a crankshaft rotatably supported inside the case in the radial direction thereof such that the axial direction of the case coincides with the direction of the rotation axis, a plurality of external tooth members having external teeth meshing with the internal teeth and eccentrically moving by the crankshaft, a rotating device for inputting a rotational force to the crankshaft, and an operating mechanism for inputting an external rotational force to the crankshaft. The crankshaft includes a first transmission gear to which the input from the rotating device is transmitted, and a second transmission gear provided adjacent to the first transmission gear and to which the input from the operating mechanism is transmitted.

[0029] Here, conventionally, when rotational forces are input to the crankshaft of a speed reducer from two systems, i.e., a rotating device and an operating mechanism, a transmission gear for inputting the rotational force of the rotating device is provided at one end of the crankshaft, and a transmission gear for inputting the rotational force of the operating mechanism is provided at the other end of the crankshaft. Therefore, the crankshaft extends in the axial direction. Also, the rotating device and the operating mechanism are arranged on the upper and lower sides, respectively. For this reason, the size of the drive device with a speed reducer as a unit becomes large. In particular, when a drive device with a speed reducer is adopted for a steering device, it is conceivable that the rotating device (motor) is arranged on the road surface side, and it is conceivable that the risk of damage increases due to flying stones, muddy water, etc. from the road surface.

[0030] Therefore, the first transmission gear and the second transmission gear are provided adjacent to each other at the end of the crankshaft. By configuring in this way, it is possible to input rotational forces from two systems, i.e., a rotating device and an operating mechanism, to the crankshaft (i.e., the speed reducer) while suppressing the size of the drive device with a speed reducer. Also, it becomes possible to arrange the rotating device at the upper part, and the influence of flying stones, etc. can be suppressed.

[0031] The drive device according to another aspect of the present invention includes a rotating device, a speed reducer having a first input shaft to which the rotational force of the rotating device is input, and a second input shaft that intersects the first input shaft and through which an external rotational force is input to the first input shaft via the second input shaft. An operating mechanism, and the rotating device, the speed reducer, and the operating mechanism are arranged on both sides with an arbitrary plane interposed therebetween.

[0032] Here, conventionally, in the case of a rotating device (motor) and a drive device, an oil seal is provided at the drive shaft portion of the rotating device so that the lubricant inside the speed reducer does not flow into the rotating device side. Since the drive shaft of the rotating device is driven at high speed rotation, an oil seal having a certain degree of tightening force is used. For this reason, the burden on the drive shaft becomes large, and this causes an extra loss. Also, generally, in terms of structure, an operating mechanism is provided above the speed reducer in the drive device. For this reason, for example, it is considered difficult to ensure a sufficient space volume inside the speed reducer while lubricating the meshing portion inside the speed reducer.

[0033] Therefore, the rotating device is arranged on one side with an arbitrary plane interposed therebetween, and the speed reducer and the operating mechanism are arranged on the other side. Under such a configuration, for example, by arranging the rotating device above the speed reducer, the oil seal provided at the drive shaft portion of the rotating device can be removed. Thereby, the burden on the drive shaft can be kept small, and it is possible to reduce extra losses (that is, improve efficiency and reduce back drive torque). Further, it is possible to prevent the lubricant on the speed reducer side from flowing into the drive shaft portion of the rotating device by gravity.

[0034] Furthermore, for example, by arranging the operating mechanism (accommodation case) on the side of the speed reducer 11, the oil level of the lubricant can be made lower than the position of the rotating device inside the speed reducer. Also, it is possible to provide a space for the entire drive device. Thereby, by eliminating the bias of the oil level of the lubricant inside the drive device, it is possible to lubricate the meshing parts and secure a sufficient space volume.

[0035] With the above configuration, the speed reducer includes a case having internal teeth, a crankshaft having a transmission gear rotatably supported on the inner side in the radial direction of the case such that the axial direction of the case becomes the rotation axis direction and disposed at one end side, and a plurality of external tooth members having external teeth meshing with the internal teeth and eccentrically moving by the crankshaft. The rotating device is disposed on the side opposite to the speed reducer with the transmission gear interposed therebetween, and the rotational force of the rotating device is input to the transmission gear. The operating mechanism may input an external rotational force to the transmission gear via the second input shaft.

[0036] A drive device according to another aspect of the present invention includes a case having internal teeth, a crankshaft rotatably supported on the inner side in the radial direction of the case such that the axial direction of the case becomes the rotation axis direction, a plurality of external tooth members having external teeth meshing with the internal teeth and eccentrically moving by the crankshaft, a rotating device for inputting a rotational force to the crankshaft, and an operating mechanism for inputting an external rotational force to the crankshaft. The reduction ratio of the crankshaft with respect to the rotating device is 4 to 5, and the speed increase ratio of the crankshaft with respect to the operating mechanism is 4 to 5.

[0037] Here, for example, in a steering device of a vehicle, when a drive device with a speed reducer is driven by a rotating device (motor), a high reduction ratio is required to reduce the power consumption of the rotating device as much as possible. Further, in order for the driver to transmit the rotation of the steering wheel, it is necessary that the steering operation by the driver be immediately output, and an operation with a low reduction ratio is required. It is preferable that both the rotational outputs of the rotational output by the rotating device and the rotational output by the driver be input to the same speed reducer and the steering be performed by the input rotational outputs. In order to input both rotational inputs to the same speed reducer and have both functions of a high reduction ratio and a low reduction ratio, it is necessary to reduce the transmission ratio from the rotating device to the speed reducer and increase the transmission ratio from the steering wheel to the speed reducer.

[0038] Therefore, the reduction ratio of the crankshaft with respect to the rotating device was set to 4 to 5, and the speed increase ratio of the crankshaft with respect to the operating mechanism was set to 4 to 5. By configuring in this way, the input from the rotating device to the crankshaft can be carried out at an appropriate reduction ratio, and it becomes possible to reduce the power load. Also, the input from the operating mechanism to the crankshaft can be carried out at an appropriate speed increase ratio, and the operation by the driver can be performed quickly. Moreover, by merely setting the reduction ratio of the crankshaft with respect to the rotating device to 4 to 5 and the speed increase ratio of the crankshaft with respect to the operating mechanism to 4 to 5, the operation by the rotating device and the operation by the driver can be suitably executed, and the drive device can be miniaturized.

[0039] The drive device according to another aspect of the present invention includes a speed reducer that connects a wheel drive unit provided in a wheel portion to an axle shaft, and a rotating device that inputs a rotational force to the speed reducer and swings the wheel drive unit in a horizontal direction with respect to the axle shaft.

[0040] Here, for example, in the automotive industry, in consideration of the impact on the environment, the electrification of automobiles (EV: Electric Vehicle) is progressing. Taking into account the progress of autonomous driving, it has become an issue to electrify driving and steering.

[0041] Therefore, the wheel drive unit is configured to swing in a horizontal direction with respect to the axle shaft by a drive device (speed reducer and rotating device). By configuring in this way, the electrification of automobiles and the progress of autonomous driving become possible. Also, the steering link portion can be omitted, and steering by steer-by-wire, which does not require mechanical connection, becomes possible. By omitting the steering link portion, the drive device can be miniaturized. Furthermore, by providing a drive device for each wheel, for example, the rotational speeds of the inner wheel and the outer wheel can be changed, so that steering with less loss becomes possible.

[0042] The drive device according to another aspect of the present invention includes a rotating device provided on a tie rod, to which a wheel drive unit provided on a wheel portion is connected via a link. By moving the tie rod in the axial direction, the rotating device swings the wheel drive unit horizontally with respect to the tie rod.

[0043] Here, for example, in the automotive industry, in consideration of the environmental impact, the electrification of automobiles (EV: Electric Vehicle) is progressing. Taking into account the automation of driving, the electrification of driving and steering has become an issue.

[0044] Therefore, the wheel drive unit is swung horizontally with respect to the tie rod by the drive device. With this configuration, the electrification and automation of automobiles become possible. In addition, the steering link portion can be omitted, enabling steering by steer-by-wire that does not require mechanical connection. By omitting the steering link portion, the drive device can be miniaturized.

Advantages of the Invention

[0045] According to the present invention, the speed reducer and the drive device can be applied to various facilities and the like, and can be miniaturized.

Brief Description of the Drawings

[0046]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

Figure 13

Figure 14

Figure 15

Figure 16

Figure 17

Figure 18

Figure 19

Figure 20

Figure 21

Figure 22

Figure 23

Figure 24

Embodiments for Carrying Out the Invention

[0047] Next, the speed reducer and the drive device according to the embodiments of the present invention will be described with reference to the drawings.

[0048] [First Embodiment] FIG. 1 is a cross-sectional view showing the drive device of the first embodiment. FIG. 2 is a cross-sectional view taken along line II-II of FIG. 1. As shown in FIGS. 1 and 2, the drive device 10 includes a speed reducer 11 and a rotating device 12 which is a drive source (for example, a motor). The drive device 10 is, for example, an eccentric swing speed reducer and is used in a steering device of a vehicle such as an automobile. The rotating device 12 is a drive source (for example, a motor) that drives the speed reducer 11.

[0049] The speed reducer 11 is, for example, an eccentric swing speed reducer and is used in a steering device of a vehicle such as an automobile. The speed reducer 11 includes a housing cylinder (case) 20, a gear unit 40, three crank assemblies 50, and a heating unit 70. The housing cylinder 20 houses the gear unit 40 and the three crank assemblies 50. The housing cylinder 20 includes a first case 21, a second case 22, and two main bearings 23. The two main bearings 23 enable relative rotational movement between the first case 21 and the second case 22. The output portion of the speed reducer 11 is exemplified by one of the first case 21 and the second case 22.

[0050] The central axis (main axis) F0 of the speed reducer 11 defined as the rotational center axis of the two main bearings 23 is shown. When the first case 21 is fixed, the second case 22 rotates around the main axis F0. When the second case 22 is fixed, the first case 21 rotates around the main axis F0. That is, one of the first case 21 and the second case 22 can rotate relative to the other of the first case 21 and the second case 22 around the main axis F0.

[0051] On the outer periphery of the first case 21 which is cylindrical, a mounting flange 24 is provided all around. A plurality of mounting holes 25 are formed at intervals on the periphery of the mounting flange 24. The mounting flange 24 is used, for example, when mounting the speed reducer 11 as an inlay.

[0052] The second case 22 includes a plurality of internal gear pins (internal teeth) 26 on its inner peripheral surface. Each internal gear pin 26 is a cylindrical member extending substantially parallel to the main shaft F0. Each internal gear pin 26 is fitted into a groove formed on the inner wall of the second case 22. Therefore, each internal gear pin 26 is properly held by the second case 22.

[0053] The plurality of internal gear pins 26 are arranged at equal intervals around the main shaft F0. The semi-peripheral surface of each internal gear pin 26 protrudes from the inner wall of the second case 22 toward the main shaft F0. Therefore, the plurality of internal gear pins 26 function as internal teeth meshing with the gear portion 40.

[0054] The first case 21 includes a base portion 27, an end plate portion 28, a positioning pin 29, and a fixing bolt 31. The first case 21 generally has a cylindrical shape. A through hole 21a concentric with the main shaft F0 is formed in the first case 21. The base portion 27 includes a substrate portion 32 and three shaft portions 33. Each of the three shaft portions 33 extends from the substrate portion 32 toward the end plate portion 28. A screw hole 35 and a reamer hole 36 are formed on the tip surface of each of the three shaft portions 33. The positioning pin 29 is inserted into the reamer hole 36. As a result, the end plate portion 28 is accurately positioned with respect to the base portion 27. The fixing bolt 31 is screwed into the screw hole 35. As a result, the end plate portion 28 is properly fixed to the base portion 27.

[0055] The gear portion 40 is disposed between the substrate portion 32 and the end plate portion 28. The three shaft portions 33 penetrate through the gear portion 40 and are connected to the end plate portion 28. The gear unit 40 includes two gears (external gear members) 41 and 42. The gear 41 is disposed between the substrate portion 32 and the gear 42 and has external teeth that mesh with a plurality of internal gear pins 26. The gear 42 is disposed between the end plate portion 28 and the gear 41 and has external teeth that mesh with a plurality of internal gear pins 26.

[0056] The shape and size of the gear 41 are substantially equal to those of the gear 42. The gears 41 and 42 orbit within the second case 22 while meshing with the internal gear pins 26. Therefore, the centers of the gears 41 and 42 will orbit around the main shaft F0.

[0057] The orbiting phase of the gear 41 is shifted by approximately 180° from the orbiting phase of the gear 42. While the gear 41 meshes with half of the plurality of internal gear pins 26, the gear 42 meshes with the remaining half of the plurality of internal gear pins 26. Therefore, the gear unit 40 can rotate the first case 21 or the second case 22.

[0058] In the first embodiment, the gear unit 40 includes two gears 41 and 42. Alternatively, more than two gears may be used as the gear unit. Further alternatively, one gear may be used as the gear unit.

[0059] Each of the three crank assemblies 50 includes a crankshaft 51, four bearings 52, 53, 54, 55, and a transmission gear 56. The three crankshafts 51 are rotation axes that are concentric with the main shaft F0, spaced apart at a predetermined interval, and spaced apart from each other in the circumferential direction. The transmission gear 56 is meshed with the gear of the drive shaft 57 of a rotating device (for example, a motor) 12 as a drive source. The transmission gear 56 directly or indirectly receives the driving force generated by the rotating device 12 as a drive source. The speed reducer 11 can appropriately set the driving force transmission path from the rotating device 12 to the transmission gear 56 according to its use environment and use conditions. Therefore, the first embodiment is not limited to a specific driving transmission path from the rotating device 12 to the transmission gear 56.

[0060] Figure 1 shows the crankshaft (transmission shaft) F2. The transmission shaft F2 is substantially parallel to the main shaft F0. The three crankshafts F2 are concentric with the main shaft F0, spaced apart by a predetermined distance, and circumferentially spaced from each other. The crankshaft 51 rotates around the transmission shaft F2. The crankshaft 51 includes two journals (crank journals) 58, 59 and two eccentric portions (eccentric bodies) 61, 62. The journals 58, 59 extend along the transmission shaft F2. The central axes of the journals 58, 59 coincide with the transmission shaft F2. The eccentric portions 61, 62 are formed between the journals 58, 59. Each of the eccentric portions 61, 62 is eccentric from the transmission shaft F2.

[0061] The journal 58 is supported by the end plate portion 28 via a bearing 52. The journal 59 is supported by the base portion 27 via a bearing 53. The eccentric portion 61 is inserted into a bearing 54. The bearing 54 is disposed between the eccentric portion 61 and the gear 41. Thus, the gear 41 undergoes an eccentric motion by the eccentric portion 61. The eccentric portion 62 is inserted into a bearing 55. The bearing 55 is disposed between the eccentric portion 62 and the gear 42. Thus, the gear 42 undergoes an eccentric motion by the eccentric portion 62.

[0062] When a driving force is input from the drive shaft 57 of the rotating device 12 to the transmission gear 56, the crankshaft 51 rotates around the transmission shaft F2. As a result, the eccentric portions 61, 62 perform an eccentric rotation around the transmission shaft F2. The gears 41, 42 connected to the eccentric portions 61, 62 via the bearings 54, 55 swing within the circular space defined by the second case 22. Since the gears 41, 42 mesh with the internal gear pins 26, a relative rotational motion is caused between the first case 21 and the second case 22.

[0063] Here, when the speed reducer 11 is used outdoors, the temperature often drops below freezing in some regions. When starting the speed reducer 11 in such an environment, the lubricant inside the speed reducer 11, especially, solidifies, making it difficult to satisfy the performance of the speed reducer 11. For example, it is also conceivable that the speed reducer 11 becomes inoperable. For example, when the speed reducer 11 is provided in the steering device of a vehicle, conventionally, the heat of the engine has been used to avoid solidification of the lubricant. However, in recent years, vehicle electrification (motor drive) has advanced, and in the case of an electrified vehicle, it is difficult to raise the temperature of the lubricant by the heat of the engine.

[0064] Therefore, for example, a heating portion 70 is provided (built in) annularly along the outer peripheral surface of the second case 22 of the housing cylinder 20. The heating portion 70 includes a heater (heating wire) 71 and an insulating portion 72. The heater 71 is connected to a power source (not shown) via a wire harness 73. The insulating portion 72 is formed of an insulating material such as rubber, for example, and is formed to cover the heater 71.

[0065] By providing the heating portion 70 along the outer peripheral surface of the second case 22, the second case 22 can be heated by the heating portion 70, for example, even in a cold region, to raise the temperature of the lubricant in the housing cylinder 20. Therefore, the viscosity (viscosity) of the lubricant can be lowered. As a result, for example, even when the speed reducer 11 is provided in a vehicle with cold-region specifications, the speed reducer 11 can be surely started. Furthermore, by providing the heating portion 70 using the second case 22 of the speed reducer 11, it is not necessary to separately prepare a dedicated mounting member for providing the heating portion 70, and the shape of the speed reducer 11 can be made compact. As a result, the speed reducer 11 can be mounted on various facilities and the like, and the range of applications can be expanded.

[0066] [Modification Example] FIG. 3 is a cross-sectional view showing a drive device according to a modification example of the first embodiment. As shown in FIG. 3, in the speed reducer 80 of the modification example, for example, a heating portion 81 is provided (built in) along the inner peripheral surface of the through hole 21a in the first case 21 of the housing cylinder 20. The other configuration of the speed reducer 80 of the modification example is the same as that of the speed reducer 11 of the first embodiment.

[0067] The heating unit 81 includes a heater (heating wire) 82 and an insulating part 83. The heater 82 is connected to a power source (not shown) via a wire harness 84. That is, the heater 82 is disposed inside the speed reducer 80, for example, by being annularly provided on the inner peripheral surface of the through hole 21a. As a result, the heater 82 is in contact with the lubricant inside the speed reducer 80. The insulating part 83 is formed of an insulating material such as rubber, for example, and is formed to cover the heater 82. The wire harness 84 is inserted through the through hole 32a of the substrate part 32 through the inside of the speed reducer 80. The inserted wire harness 84 is fixed to the substrate part 32 by a fixing part 85.

[0068] In the heating unit 81, the heater 82 is disposed inside the speed reducer 80 and is in contact with the lubricant. Therefore, the lubricant can be directly heated by the heater 82, so that the temperature of the lubricant can be increased more efficiently. As a result, for example, even when the speed reducer 80 is provided in a vehicle with specifications for cold regions, the speed reducer 80 can be surely started. Furthermore, by providing the heating unit 81 inside the speed reducer 80 by utilizing the inner peripheral surface of the through hole 21a of the speed reducer 80, it is not necessary to separately prepare a dedicated mounting member for providing the heating unit 81, and the shape of the speed reducer 80 can be made compact. As a result, the speed reducer 80 can be mounted on various facilities and the like, and the range of applications can be expanded.

[0069] Hereinafter, the second to eleventh embodiments will be described with reference to FIGS. 4 to 24. In the second to eleventh embodiments, the same or similar members as those in the first embodiment are denoted by the same reference numerals, and detailed descriptions thereof are omitted.

[0070] [Second Embodiment] FIG. 4 is a cross-sectional view showing the speed reducer of the second embodiment. As shown in FIG. 4, in the speed reducer 90 of the second embodiment, the number of internal gear pins 26 is set to 80 to 120, and the eccentricity of the crankshaft 51 is set to 1.3 mm or less. Other configurations of the speed reducer 90 of the second embodiment are the same as those of the speed reducer 11 of the first embodiment.

[0071] In this way, the internal gear pins 26 are set to increase by 80 to 120 compared to ordinary internal gear pins. That is, the internal teeth of the second case 22 are set to have 80 to 120 teeth. Also, the eccentricity of the crankshaft 51 is set to be reduced to 1.3 mm or less compared to the ordinary eccentricity. The reasons for setting the internal gear pins 26 to 80 to 120 and setting the eccentricity of the crankshaft 51 to 1.3 mm or less are as follows.

[0072] That is, when the speed reducer 90 is provided in the steering device, as requirements for the speed reducer 90 provided in the steering device, it is necessary to be lightweight, compact, and have high load resistance. The steering device assists with a rotating device such as a motor while the operation by the driver is also performed simultaneously. For this reason, it is required to perform steering without a sense of discomfort in the feeling and sensation (feeling) applied to the steering wheel. Furthermore, since a mechanism that performs an eccentric swinging motion is provided inside the speed reducer 90, it is necessary to cause a smooth eccentric swinging motion.

[0073] Therefore, the internal gear pins 26 are set to increase by 80 to 120. By increasing the number of pins of the internal gear pins 26 to 80 to 120, the internal gear pins 26 that receive loads from the gears 41 and 42 of the gear unit 40 can be increased. As a result, the speed reducer 90 can cope with high load resistance while remaining in a compact state. Also, the eccentricity of the crankshaft 51 is set to be reduced to 1.3 mm or less. By reducing the eccentricity of the crankshaft 51 to 1.3 mm or less, the amount of vibration of the crankshaft 51 and the gear unit 40 (gears 41 and 42) can be suppressed to a small level. As a result, there is no sense of discomfort for the driver, and the speed reducer 90 can rotate smoothly.

[0074] [Third Embodiment] FIG. 5 is a cross-sectional view showing the drive device of the third embodiment. As shown in Fig. 5, the drive device 100 of the third embodiment is obtained by removing the heating unit 70 from the speed reducer 11 of the first embodiment, further replacing the housing cylinder 20 with a housing cylinder (case) 101, and additionally providing an operating mechanism 102. Other configurations of the drive device 100 of the third embodiment are the same as those of the drive device 10 of the first embodiment.

[0075] The housing cylinder 101 includes, for example, a first case 105, a second case 22, and a third case 106. The housing cylinder 101 houses the gear unit 40 and three crank assemblies 50. That is, the housing cylinder 101 forms the case of the speed reducer. The first case 105 includes, for example, a base portion 27 and an end plate portion 107. The end plate portion 107 has a first housing case 109 on the end plate portion 28 of the first embodiment. The first housing case 109 is a case that forms one of the housing cases 108 for housing the operating mechanism 102. The third case 106 is attached to the end plate portion 107 in a sealed state by a plurality of bolts 111.

[0076] The third case 106 has a case portion 112 and a second housing case 113. The second housing case 113 is a case that forms the other of the housing cases 108 for housing the operating mechanism 102. The housing case 108 is formed by the first housing case 109 and the second housing case 113. The main part of the operating mechanism 102 is housed in the housing case 108.

[0077] The operating mechanism 102 includes an operating shaft 115, a first bevel gear 116, a second bevel gear 117, an intermediate shaft 118, and an intermediate gear 119. The operating shaft 115 is rotatably supported by a support portion 126 via a bearing 127. The support portion 126 is fixed to the housing case 108. A first bevel gear 116 is coaxially formed at the tip of the operation shaft 115. A second bevel gear 117 is meshed with the first bevel gear 116. The second bevel gear 117 is coaxially provided on an intermediate shaft 118. The intermediate shaft 118 is arranged to be orthogonal to the operation shaft 115 and is rotatably supported in the housing case 108 via a bearing 128. An intermediate gear 119 is coaxially provided on the intermediate shaft 118. The intermediate gear 119 is meshed with a transmission gear 56.

[0078] The operating mechanism 102 is configured as an orthogonal input part by arranging the intermediate shaft 118 to be orthogonal to the operation shaft 115. For example, when the driver operates and rotates the operation shaft 115, the rotational force of the operation shaft 115 is transmitted to the first bevel gear 116. The rotational force of the first bevel gear 116 is transmitted to the transmission gear 56 via the second bevel gear 117, the intermediate shaft 118, and the intermediate gear 119.

[0079] A rotating device 12 is attached to the case part 112 of the third case 106. The rotating device 12 includes a device case 121 and a device main body 122. The device case 121 is formed in a U-shaped cross section, and the part facing the case part 112 is open. The device main body 122 is housed inside the device case 121. Also, the opening of the device case 121 is covered by the case part 112. That is, the case part 112 forms a part of the case of the speed reducer and also forms a part of the device case 121. The reason why the case part 112, which forms a part of the case of the speed reducer, also forms a part of the case of the rotating device 12 is as follows.

[0080] That is, generally, a rotating device (e.g., a motor) has the entire device body (e.g., a motor body) covered by a mechanism case. Therefore, when the rotating device is attached to a speed reducer, at the attached part, the case of the speed reducer and the case of the rotating device overlap. Further, for example, in order to attach the case of the rotating device to the case of the speed reducer with bolts or the like, it is necessary to form screw holes in the case of the speed reducer. For this reason, the plate thickness of the case of the speed reducer increases.

[0081] By the way, the drive shaft of the rotating device penetrates through the case of the rotating device and the case of the speed reducer and is disposed inside the speed reducer. Therefore, it is conceivable that the drive shaft of the rotating device becomes long and the inertia increases. For this reason, it is conceivable that the burden on the rotating device increases. Also, since the case of the speed reducer and the case of the rotating device overlap, it becomes difficult to make the drive device flat (i.e., compact).

[0082] Therefore, the case part 112 of the housing cylinder 101 of the speed reducer that faces the rotating device 12 is also used as a part of the case of the rotating device 12. Therefore, a configuration can be adopted in which only the case part 112 is interposed between the speed reducer and the rotating device 12. Thereby, the drive shaft 57 of the rotating device 12 can be shortened and the inertia can be suppressed low, and the burden on the rotating device can be suppressed small. Also, the drive device 100 can be made flat (i.e., compact).

[0083] [Fourth Embodiment] FIG. 6 is a cross-sectional view showing the drive device of the fourth embodiment. As shown in FIG. 6, the drive device 140 of the fourth embodiment replaces the housing case 108 of the drive device 100 of the third embodiment with a housing case 141, replaces the operation mechanism 102 with an operation mechanism 142, and further includes a detection unit 143. Other configurations of the drive device 140 of the fourth embodiment are the same as those of the drive device 100 of the third embodiment.

[0084] The housing case 141 is formed in the same manner as the housing case 108 of the third embodiment, and thus a detailed description thereof will be omitted. The operating mechanism 142 is obtained by dividing the operating shaft 115 of the third embodiment into a first operating shaft 144 and a second operating shaft 145. The first operating shaft 144 is rotatably supported by the support portion 126 via a bearing 146. The base end portion of the first operating shaft 144 protrudes from the support portion 126 to the outside of the housing case 108. The second operating shaft 145 is rotatably supported by the support portion 126 via a bearing 147. A first bevel gear 116 is provided coaxially at the tip of the second operating shaft 145.

[0085] The detection unit 143 is provided with, for example, a torsion bar 148 and a rotor 149 or the like at the tip of the first operating shaft 144 and the base end of the second operating shaft 145. The torsion bar 148 is accommodated in, for example, an accommodation hole at the tip of the first operating shaft 144 and an accommodation hole at the base end of the second operating shaft 145. The torsion bar 148 is fixed to the first operating shaft 144 and the second operating shaft 145 with, for example, a spring pin 152. The detection unit 143 can detect, for example, the rotation angles of the first operating shaft 144 and the second operating shaft 145 with a rotor 149 or the like. Further, the detection unit 143 can detect, for example, the torque generated between the first operating shaft 144 and the second operating shaft 145 with a torsion bar 148 or the like, simultaneously with the rotation angle. The reason for providing the detection unit 143 on the first operating shaft 144 and the second operating shaft 145 of the operating mechanism 142 is as follows.

[0086] That is, in a vehicle steering device, in order to perform automatic steering and assist control toward automation and electrification, it is required to mount sensors (for example, a detection unit that detects a rotation angle and torque). For this reason, sensors that can be mounted in the in-vehicle space of current vehicles are required. Also, due to the structure of current vehicles, for example, the crankshaft (rotating shaft) 51 of the speed reducer is arranged orthogonally to the first operating shaft 144 and the second operating shaft 145 connected to the steering wheel. Therefore, for example, a first bevel gear 116 is provided on the second operating shaft 145 of the operating mechanism 142, and a detection unit 143 is further provided on the first operating shaft 144 and the second operating shaft 145.

[0087] By configuring in this way, the operating mechanism 142 including the first bevel gear 116 and the detection unit 143 can be compactly integrated. Therefore, for example, sensors (such as the detection unit 143) necessary for automatic steering and assist control can be mounted in a small space of a current vehicle, enabling orthogonal axis input from the first operating shaft 144 connected to the steering wheel. Specifically, for example, when the first operating shaft 144 is operated to input a rotational force to the crankshaft 51, the detection unit 143 detects the rotational angle and torque. By controlling the rotating device 12 based on the rotational angle and torque detected by the detection unit 143, the reduction gear can be operated by the rotating device 12. Thereby, the operation of the driver can be assisted by the detection unit 143 and the rotating device 12.

[0088] [Fifth Embodiment] FIG. 7 is a cross-sectional view showing an example in which the driven bevel gear of the drive device according to the fifth embodiment is arranged on the reduction gear side. FIG. 8 is a cross-sectional view showing an example in which the driven bevel gear of the drive device according to the fifth embodiment is arranged on the side opposite to the reduction gear. As shown in FIG. 7, the drive device 160 according to the fifth embodiment is obtained by replacing the operating mechanism 142 of the fourth embodiment with an operating mechanism 162. Other configurations of the drive device 160 according to the fifth embodiment are the same as those of the drive device 140 according to the fourth embodiment.

[0089] The operating mechanism 162 is obtained by removing the detection unit 143 from the operating mechanism 142 of the fourth embodiment, replacing the first operating shaft 144 and the second operating shaft 145 with an operating shaft 115, and replacing the intermediate shaft 118 with an intermediate shaft 164. The intermediate shaft 164 has first locking portions such as splines, serrations, key grooves, etc. formed on the outer peripheral surfaces of the first meshing position 164a and the second meshing position 164b. The first meshing position 164a is the end of the intermediate shaft 164 on the side of the intermediate gear 119 (i.e., the speed reducer). The second meshing position 164b is the end of the intermediate shaft 164 on the side opposite to the intermediate gear 119 (i.e., the speed reducer).

[0090] The second bevel gear (driven bevel gear) 117 has second locking portions such as splines, serrations, key grooves, etc. formed on the inner peripheral surface. The second locking portions are formed so as to engage with the first locking portions of the first meshing position 164a and the second meshing position 164b. Thereby, the second bevel gear 117 is detachably attached to the first meshing position 164a and the second meshing position 164b of the intermediate shaft 164 with its direction changed. That is, the second bevel gear 117 can be attached to the first meshing position 164a and the second meshing position 164b with its direction changed and switchably.

[0091] As shown in FIG. 7, the second bevel gear 117 is attached to the first meshing position 164a. Therefore, according to the drive device 160, by transmitting a rotational force to the operating shaft 115 of the operating mechanism 162, for example, in the clockwise direction as indicated by the arrow A, the rotational force of the operating shaft 115 is transmitted to the first bevel gear (drive bevel gear) 116. Due to the rotational force of the first bevel gear 116, a rotational force in the direction of arrow B is transmitted to the second bevel gear 117 and the intermediate shaft 118. The rotational force of the intermediate shaft 118 is transmitted to the transmission gear 56 via the intermediate gear 119. Also, by transmitting a rotational force to the operating shaft 115, for example, in the counterclockwise direction as indicated by the arrow C, the rotational force of the operating shaft 115 is transmitted to the first bevel gear 116. Due to the rotational force of the first bevel gear 116, a rotational force in the direction of arrow D is transmitted to the second bevel gear 117 and the intermediate shaft 118.

[0092] As shown in FIG. 8, the second bevel gear 117 is attached to the second meshing position 164b. Therefore, according to the drive device 160, by transmitting a rotational force to the operating shaft 115 of the operating mechanism 162, for example, in the clockwise direction as indicated by arrow A, the rotational force of the operating shaft 115 is transmitted to the first bevel gear 116. Due to the rotational force of the first bevel gear 116, a rotational force in the direction of arrow D is transmitted to the second bevel gear 117 and the intermediate shaft 118. The rotational force of the intermediate shaft 118 is transmitted to the transmission gear 56 via the intermediate gear 119. Also, by transmitting a rotational force to the operating shaft 115, for example, in the counterclockwise direction as indicated by arrow C, the rotational force of the operating shaft 115 is transmitted to the first bevel gear 116. Due to the rotational force of the first bevel gear 116, a rotational force in the direction of arrow B is transmitted to the second bevel gear 117 and the intermediate shaft 118. As shown in FIGS. 7 and 8, by only switching the second bevel gear 117 between the first meshing position 164a and the second meshing position 164b of the intermediate shaft 164, the rotational direction of the second bevel gear 117 with respect to the rotation of the first meshing position 164a can be reversed.

[0093] Here, the steering device has a difference between a right-hand steering wheel and a left-hand steering wheel depending on the vehicle type and the country of use. For this reason, the steering device is designed differently depending on the difference between the right-hand steering wheel and the left-hand steering wheel. In order to accommodate both the right-hand steering wheel and the left-hand steering wheel, for example, it is accommodated by changing the layout of the operating mechanism on the vehicle, changing the screw direction of the built-in ball screw for steering, etc.

[0094] Therefore, in the operating mechanism 162, by only switching the second bevel gear 117 between the first meshing position 164a and the second meshing position 164b of the intermediate shaft 164, the rotational direction of the second bevel gear 117 with respect to the rotation of the first meshing position 164a is reversed. Thereby, the rotation of the second bevel gear 117 can be changed without changing the design of any parts other than changing the mounting position of the second bevel gear 117. Also, the operating mechanism 16 can be made compact, and the drive device 160 can be made compact.

[0095] [Sixth Embodiment] Figure 9 is a cross-sectional view of the drive device according to the sixth embodiment. As shown in FIG. 9, the drive device 170 according to the sixth embodiment is obtained by replacing the crankshaft 51 of the fifth embodiment with a crankshaft 171. Other configurations of the drive device 170 according to the sixth embodiment are the same as those of the drive device 160 according to the fifth embodiment. The crankshaft 171 includes a first transmission gear 172 and a second transmission gear 173 at an end on the side of the rotating device 12.

[0096] The first transmission gear 172 is a spur gear attached to the end of the crankshaft 171. The first transmission gear 172 is meshed with the gear of the drive shaft 57 of the rotating device 12. That is, a rotational force is input to the first transmission gear 172 from the rotating device 12. Thereby, the rotational force input from the rotating device 12 is input to the crankshaft 171 via the first transmission gear 172.

[0097] The second transmission gear 173 is a small gear formed (machined) adjacent to the first transmission gear 172 at the end of the crankshaft 171. The second transmission gear 173 is meshed with the intermediate gear 176 of the operation mechanism 175. The operation mechanism 175 is obtained by replacing the intermediate gear 119 of the operation mechanism 162 of the fifth embodiment with an intermediate gear 176. A rotational force is input to the second transmission gear 173 from the operation mechanism 175. Thereby, the rotational force input from the operation mechanism 175 is input to the crankshaft 171 via the second transmission gear 173. In this way, by providing the first transmission gear 172 and the second transmission gear 173 adjacent to each other at the end of the crankshaft 171, a rotational force can be input to the crankshaft 171 (that is, the speed reducer) from two systems, namely the rotating device 12 and the operation mechanism 175.

[0098] Here, conventionally, when rotational force is input to the crankshaft of a speed reducer from two systems, namely a rotating device and an operating mechanism, for example, a transmission gear for inputting the rotational force of the rotating device is provided at one end of the crankshaft, and a transmission gear for inputting the rotational force of the operating mechanism is provided at the other end of the crankshaft. Therefore, the crankshaft extends in the axial direction. Also, the rotating device and the operating mechanism are arranged on the upper and lower sides respectively. For this reason, the size of the drive device with a speed reducer as a unit becomes large. In particular, when a drive device with a speed reducer is adopted for a steering device, it is conceivable that a rotating device (motor) is arranged on the road surface side, and it is considered that the risk of damage increases due to flying stones, muddy water, etc. from the road surface.

[0099] Therefore, the first transmission gear 172 and the second transmission gear 173 are provided adjacent to each other at the end of the crankshaft 171. Thereby, with the shape of the drive device 170 suppressed to be compact, rotational force can be input to the crankshaft 171 (that is, the speed reducer) from two systems, namely the rotating device 12 and the operating mechanism 175. Also, the rotating device 12 can be arranged at the upper part, and the influence by flying stones, etc. can be suppressed.

[0100] [Modification Example 1] FIG. 10 is also a cross-sectional view of the drive device of Modification Example 1 of the sixth embodiment. As shown in FIG. 10, the drive device 180 of Modification Example 1 is obtained by replacing the second transmission gear 173 of the sixth embodiment with a second transmission gear 181. Other configurations of the drive device 180 of Modification Example 1 are the same as those of the drive device 170 of the sixth embodiment.

[0101] That is, in the drive device 180, the first transmission gear 172 is attached to the end of the crankshaft 182. A flange 183 of the second transmission gear 181 is attached to the first transmission gear 172 with a plurality of bolts 184. The second transmission gear 181 has a small gear 185 formed (machined) on the protruding portion. Therefore, the second transmission gear 181 (specifically, the pinion gear 185) is provided adjacent to the first transmission gear 172 on the end side of the crankshaft 182. The pinion gear 185 is meshed with the intermediate gear 176.

[0102] In this way, the first transmission gear 172 and the second transmission gear 181 are provided adjacent to each other at the end of the crankshaft 182. As a result, with the shape of the drive device 180 suppressed to be compact, the rotational force can be input to the crankshaft 182 (that is, the speed reducer) from two systems, the rotating device 12 and the operating mechanism 175. Also, it becomes possible to arrange the rotating device 12 at the upper part, and the influence by flying stones and the like can be suppressed.

[0103] [Modification Example 2] FIG. 11 is a cross-sectional view of the drive device according to Modification Example 2 of the sixth embodiment. As shown in FIG. 11, the drive device 190 of Modification Example 2 is obtained by replacing the second transmission gear 181 of Modification Example 1 with a second transmission part 191. Other configurations of the drive device 190 of Modification Example 2 are the same as those of the drive device 180 of Modification Example 1.

[0104] The second transmission part 191 includes a connecting part 192 and a second transmission gear 196. In the connecting part 192, the flange 193 is attached to the first transmission gear 172 with a plurality of bolts 194. An annular second transmission gear 196 is fitted to the protruding part 195 of the connecting part 192. The protruding part 195 and the second transmission gear 196 are fixed with a key 197. The second transmission gear 196 is meshed with the intermediate gear 176. A plate 198 is fixed to the convex surface of the protruding part 195 with bolts 199.

[0105] In this way, the first transmission gear 172 and the second transmission gear 196 are provided adjacent to each other at the end of the crankshaft 182. As a result, with the shape of the drive device 190 suppressed to be compact, the rotational force can be input to the crankshaft 182 (that is, the speed reducer) from two systems, the rotating device 12 and the operating mechanism 175. In addition, the rotating device 12 can be arranged at the upper part, and the influence by flying stones or the like can be suppressed.

[0106] [Modification Example 3] FIG. 12 is a cross-sectional view of the drive device according to Modification Example 3 of the sixth embodiment. As shown in FIG. 12, the drive device 210 of Modification Example 3 is obtained by replacing the second transmission gear 173 of the sixth embodiment with the second transmission gear 211. Other configurations of the drive device 210 of Modification Example 3 are the same as those of the drive device 170 of the sixth embodiment.

[0107] The crankshaft 212 of the drive device 210 has an engaging portion such as a spline or serration formed at the end. The first transmission gear 172 and the second transmission gear 211 are adjacently attached to the end of the crankshaft 212. The second transmission gear 211 is meshed with the intermediate gear 176. The intermediate gear 176 is attached to the intermediate shaft 177.

[0108] In this way, the first transmission gear 172 and the second transmission gear 211 are provided adjacent to each other at the end of the crankshaft 212. Thereby, with the shape of the drive device 210 suppressed to be compact, the rotational force can be input to the crankshaft 212 (that is, the speed reducer) from two systems, namely, the rotating device 12 and the operating mechanism 175. In addition, the rotating device 12 can be arranged at the upper part, and the influence by flying stones or the like can be suppressed.

[0109] [Modification Example 4] FIG. 13 is a cross-sectional view of the drive device according to Modification Example 4 of the sixth embodiment. As shown in FIG. 13, the drive device 220 of Modification Example 4 is obtained by replacing the second transmission gear 211 of Modification Example 3 with the second transmission gear 221. Other configurations of the drive device 220 of Modification Example 4 are the same as those of the drive device 210 of Modification Example 3.

[0110] The second transmission gear 221 is attached to the end of the crankshaft 212 adjacent to the first transmission gear 172. The second transmission gear 221 is formed as a bevel gear and meshes with the first bevel gear 116. By attaching the bevel gear-shaped second transmission gear 221 to the end of the crankshaft 212, the intermediate gear 176 and the intermediate shaft 177 can be removed from the operating mechanism 175 of the third modification. Therefore, the distance L from the operating mechanism 222 of the fourth modification to the flange 224 of the housing cylinder (case) 223 can be kept small.

[0111] In this way, the first transmission gear 172 and the second transmission gear 221 are provided adjacent to each other at the end of the crankshaft 212. As a result, with the shape of the drive device 220 suppressed to be compact, rotational force can be input to the crankshaft 212 from two systems, namely the rotating device 12 and the operating mechanism 175, to the crankshaft 212 (i.e., the speed reducer). Also, the rotating device 12 can be arranged at the upper part, and the influence of flying stones and the like can be suppressed. Furthermore, by forming the second transmission gear 221 as a bevel gear, the distance L from the operating mechanism 222 to the flange 224 can be kept small, and the shape of the drive device 220 can be made more compact.

[0112] [Seventh Embodiment] FIG. 14 is a cross-sectional view showing the drive device of the seventh embodiment. As shown in FIG. 14, the drive device 230 of the seventh embodiment is obtained by arranging the drive device 160 of the fifth embodiment shown in FIG. 8 horizontally and disposing the operating mechanism 162 on the side of the speed reducer 11. Other configurations of the drive device 230 of the seventh embodiment are the same as those of the drive device 160 of the fifth embodiment.

[0113] That is, in the drive device 230, the main shaft F0 of the speed reducer 11 is arranged vertically. Therefore, the transmission gear 56 is arranged above the housing cylinder 20 (specifically, the end plate portion 28) of the speed reducer 11. A drive shaft 57 is meshed with the transmission gear 56. By arranging the drive shaft 57 vertically, the rotating device 12 is arranged above the speed reducer 11.

[0114] Further, an intermediate gear 119 is meshed with the transmission gear 56. The intermediate gear 119 is attached to the upper end of the intermediate shaft 164. The intermediate shaft 164 is vertically arranged. A second bevel gear 117 is attached adjacent to the lower side of the intermediate gear 119 on the intermediate shaft 164. A first bevel gear 116 is meshed with the second bevel gear 117. The operating shaft 115 provided with the first bevel gear 116 is arranged below the second bevel gear 117. Thereby, the operating mechanism 162 is arranged on the side of the speed reducer 11. The main part of the operating mechanism 162 is accommodated in the accommodation case 232. The accommodation case 232 is arranged on the side of the speed reducer 11. Lubricants for lubricating meshing parts and the like are stored inside the speed reducer 11 (i.e., the housing cylinder 20), inside the accommodation case 232, and the like.

[0115] Here, for example, generally in the case of a rotating device (motor) and a driving device, an oil seal is provided on the drive shaft portion of the rotating device so that the lubricant inside the speed reducer does not flow into the rotating device side. Since the drive shaft of the rotating device is driven at high speed rotation, an oil seal with a certain degree of tightening force is used. For this reason, the burden on the drive shaft becomes large, and this becomes an extra loss. Also, generally, in terms of structure, an operating mechanism is provided above the speed reducer in the driving device. For this reason, for example, it may be considered difficult to ensure a sufficient space volume inside the speed reducer while lubricating the meshing parts inside the speed reducer.

[0116] Therefore, the rotating device 12 is arranged above the speed reducer 11. Thus, the oil seal provided on the drive shaft 57 of the rotating device 12 can be removed. Thereby, the burden on the drive shaft 57 can be kept small, and reduction of extra loss (i.e., improvement of efficiency, reduction of back drive torque) becomes possible. Also, the lubricant of the speed reducer 11 can be prevented from flowing into the interior along the drive shaft 57 of the rotating device 12 by gravity.

[0117] Furthermore, the housing case 232 is arranged on the side of the speed reducer 11. Thus, inside the speed reducer 11, the oil level of the lubricant can be made lower than the position of the rotating device 12. Also, it becomes possible to provide space for the entire driving device 230. As a result, by eliminating the bias of the oil level of the lubricant inside the driving device 230, it becomes possible to lubricate the meshing parts while ensuring a sufficient space volume. Also, by arranging the housing case 232 on the side of the speed reducer 11, the driving device 230 can be made more compact.

[0118] [Eighth Embodiment] FIG. 15 is a cross-sectional view showing the driving device of the eighth embodiment. As shown in FIG. 15, the driving device 240 of the eighth embodiment has a reduction ratio of the crankshaft 171 to the rotating device 12 in the driving device 170 of the sixth embodiment set to 4 to 5, and a speed increase ratio of the crankshaft 171 to the operating mechanism 175 set to 4 to 5. Other configurations of the driving device 240 of the eighth embodiment are the same as those of the sixth embodiment.

[0119] That is, in the driving device 240, the reduction ratio by the drive shaft 57 of the rotating device 12 and the first transmission gear 172 is set to 4 to 5. Also, in the driving device 240, the speed increase ratio by the first bevel gear 116, the second bevel gear 117, the intermediate gear 176, and the second transmission gear 173 is set to 4 to 5.

[0120] Here, for example, in a vehicle steering device, when a driving device with a speed reducer is driven by a rotating device (motor), a high reduction ratio is required to minimize the power consumption of the rotating device. Further, in order for the driver to transmit the rotation of the steering wheel, the steering operation by the driver needs to be output immediately, and an operation with a low reduction ratio is required.

[0121] It is preferable that the rotational outputs of both the rotational machine and the driver are input to the same speed reducer and steered by the input rotational output. In order to input the rotational inputs of both to the same speed reducer and provide both functions of a high reduction ratio and a low reduction ratio, it is necessary to reduce the transmission ratio from the rotational machine to the speed reducer and increase the transmission ratio from the steering wheel to the speed reducer.

[0122] Therefore, the reduction ratio of the crankshaft 171 with respect to the rotary device 12 was set to 4 to 5, and the speed increase ratio of the crankshaft 171 with respect to the operation mechanism 175 was set to 4 to 5. By configuring in this way, the input from the rotary device 12 to the crankshaft 171 can be performed at an appropriate reduction ratio, and the power load can be reduced. Also, the input from the operation mechanism 175 to the crankshaft 171 can be performed at an appropriate speed increase ratio, and the operation by the driver can be performed quickly. Moreover, by simply setting the reduction ratio of the crankshaft 171 with respect to the rotary device 12 to 4 to 5 and the speed increase ratio of the crankshaft 171 with respect to the operation mechanism 175 to 4 to 5, the operation by the rotary device 12 and the operation by the driver can be suitably executed, and the drive device 240 can be made compact.

[0123] [Embodiment 9] FIG. 16 is a cross-sectional view showing the drive device of the ninth embodiment. FIG. 17 is an enlarged cross-sectional view of the sleeve and the oil seal of the ninth embodiment. As shown in FIGS. 16 and 17, the drive device 300 of the ninth embodiment is provided with a sleeve 301 and an oil seal (seal) 302 on the drive device 210 of the modified example 3 of the sixth embodiment. Other configurations of the drive device 300 of the ninth embodiment are the same as those of the drive device 210 of the modified example 3.

[0124] As shown in FIGS. 16 and 17, an annular groove portion 304 is formed on the end plate portion 28 of the first case 21 on the surface facing the second case 22. One end portion 22a of the second case 22 is inserted into the groove portion 304 of the end plate portion 28. An annular sleeve 301 is provided between the outer peripheral wall 304a of the groove portion 304 and one end portion 22a of the second case 22. The sleeve 301 is formed in a crank-shaped cross section by, for example, an inner end portion 305, a first wall portion 306, and a second wall portion 307.

[0125] The inner end portion 305 is in contact with one end face 22b of the second case 22. Therefore, the sleeve 301 is positioned by, for example, one end face 22b of the second case 22. Further, the first wall portion 306 is in contact with one end portion 22a of the second case 22 (specifically, the outer peripheral surface of the one end portion 22a). The sleeve 301 is fixed (provided) to one end portion 22a of the second case 22, for example.

[0126] The second wall portion 307 projects annularly from the first wall portion 306 to the step portion 309 of the end plate portion 28 and is disposed non-contact with the step portion 309. By disposing the second wall portion 307 at the step portion 309 of the end plate portion 28, for example, a gap between the second wall portion 307 and the step portion 309 can be formed in a labyrinth shape. Therefore, relative rotational movement is allowed between the sleeve 301 and the first case 21, and entry of water, light, etc. can be suitably suppressed from the gap between the second wall portion 307 and the step portion 309. Thereby, the space between the outer peripheral wall 304a of the groove portion 304 and one end portion 22a of the second case 22 is suitably closed by the second wall portion 307 of the sleeve 301.

[0127] Further, an annular oil seal 302 is provided inside the second wall portion 307 in the groove portion 304. In the oil seal 302, a seal body 311 is in contact with the outer peripheral wall 304a of the groove portion 304 and the first wall portion 306, and further, a lip 312 is in contact with the first wall portion 306. Thereby, the oil seal 302 can seal between the outer peripheral wall 304a of the groove portion 304 and the first wall portion 306. Further, the oil seal 302 is covered from the outside of the groove portion 304 by the sleeve 301. The sleeve 301 is formed, for example, in a crank shape so as to have a shape in which rainwater, washing water, sunlight, etc. do not hit the oil seal 302. The reason for forming the sleeve 301 is as follows.

[0128] That is, when the speed reducer is used outdoors, especially in a special environment such as in-vehicle use, external factors that have not had an impact conventionally, such as rain, high-pressure washing, ultraviolet rays, flying stones, etc., increase. For this reason, at present, there is no speed reducer that can guarantee use outdoors. By the way, for example, sleeves are generally used for cleaning robots, but it is difficult to prevent external factors such as rain, high-pressure washing, ultraviolet rays, flying stones, etc. with these shapes.

[0129] Therefore, the sleeve 301 is formed, for example, in a crank shape and is securely fixed to the second case 22 so as to preferably close the space (gap) between the outer peripheral wall 304a of the groove portion 304 and one end portion 22a of the second case 22 with the sleeve 301. Thus, the oil seal 302 can be well (securely) covered with the sleeve 301. Thereby, the oil seal 302 can be protected from external factors such as rain, high-pressure washing, ultraviolet rays, flying stones, etc. by the sleeve 301. Also, the sleeve 301 is provided on the second case 22. Thereby, a dedicated part for attaching the sleeve 301 can be made unnecessary, and the speed reducer can be made more compact.

[0130] [Modification Example 1] FIG. 18 is a cross-sectional view showing Modification Example 1 of the oil seal of the ninth embodiment. As shown in FIG. 18, the oil seal (seal) 320 of Modification Example 1 is obtained by adding a lip 322 (hereinafter referred to as the second lip 322) to the oil seal 302 of the ninth embodiment. Other configurations of the oil seal 320 of Modification Example 1 are the same as those of the oil seal 302 of the ninth embodiment. That is, the oil seal 320 has a first lip 312 and a second lip 322. The first lip 312 contacts the first wall portion 306. The second lip 322 contacts the second wall portion 307. Therefore, the oil seal 320 can seal between the outer peripheral wall 304a of the groove portion 304 and the first wall portion 306, and can also seal between the outer peripheral wall 304a of the groove portion 304 and the second wall portion 307. Thereby, the sealing performance by the oil seal 320 can be further enhanced.

[0131] [Modification Example] FIG. 19 is a cross-sectional view of Modification Example 2 showing an example in which the positions of the sleeve and the oil seal of the ninth embodiment are changed. As shown in FIG. 19, the sleeve 301 and the oil seal 302 are provided between the substrate portion 32 of the first case 21 and the other end portion 22c of the second case 22. By providing the sleeve 301 and the oil seal 302 between the substrate portion 32 of the first case 21 and the other end portion 22c of the second case 22, the sleeve 301 and the oil seal 302 can seal between the substrate portion 32 and the other end portion 22c of the second case 22. Furthermore, the oil seal 302 between the substrate portion 32 and the other end portion 22c of the second case 22 can be protected by the sleeve 301 from external factors such as rain, high-pressure washing, ultraviolet rays, and flying stones.

[0132] [Tenth Embodiment] FIG. 20 is a plan view showing a steering device having the drive device of the tenth embodiment. FIG. 21 is a front view showing a steering device having the drive device of the tenth embodiment. FIG. 22 is a plan view for explaining an example of steering the steering device with the drive device of the tenth embodiment.

[0133] As shown in FIGS. 20 and 21, the steering device 250 includes an axle shaft 251, a drive device 252, a connecting portion 253, a wheel drive portion (in-wheel motor) 254, and a wheel portion 255. The axle shaft 251 extends in the width direction of a vehicle (not shown). Drive devices 252 are provided at both ends of the axle shaft 251.

[0134] The drive device 252 includes, for example, a speed reducer 257 and a rotating device (motor) 258. For the speed reducer 257 and the rotating device 258, for example, the speed reducer and the rotating device of the first to ninth embodiments are used. The speed reducer 257 has, for example, a case attached to the end of the axle shaft 251 and an output portion attached to the connecting portion 253. The drive shaft of the rotating device 258 is connected to the input shaft of the speed reducer 257 so as to be able to transmit a rotational force. A wheel drive portion 254 is attached to the connecting portion 253. The output portion of the wheel drive portion 254 is attached to the wheel portion 255.

[0135] The drive device 252 is provided for each wheel (wheel portion 255). Further, the speed reducer 257 connects the wheel drive portion 254 provided on the wheel portion 255 to the end of the axle shaft 251 via the output portion. Furthermore, the rotating device 258 inputs a rotational force to the input shaft of the speed reducer 257 to swing the wheel drive portion 254 in the horizontal direction with respect to the axle shaft 251. The wheel drive portion 254 is, for example, an in-wheel motor that rotates the wheel portion 255 and also serves as a regenerative brake.

[0136] Here, for example, in the automotive industry, in consideration of the impact on the environment, the electrification of automobiles (EV: Electric Vehicle) is progressing. Taking automated driving into account, it has become an issue to electrify driving and steering.

[0137] Therefore, as shown in FIG. 22, the wheel drive portion 254 is swung in the horizontal direction with respect to the axle shaft 251 by the drive device 252 (speed reducer 257 and rotating device 258). By configuring in this way, electrification and automated driving of automobiles become possible. In addition, the steering link portion can be omitted, and steering by steer-by-wire that does not require mechanical connection becomes possible. By omitting the steering link portion, the drive device 252 can be made compact. Furthermore, by providing the drive device 252 for each wheel, for example, the rotation speeds of the inner wheel and the outer wheel can be changed, so that steering with less loss becomes possible.

[0138] [Embodiment 11] FIG. 23 is a plan view showing a steering device including the drive device of the 11th embodiment. FIG. 24 is a plan view for explaining an example of steering the steering device with the drive device of the 11th embodiment.

[0139] As shown in FIG. 23, the steering device 270 includes a tie rod 271, a drive device 272, a link 273, a connecting portion 274, a wheel drive unit (in-wheel motor) 275, and a wheel portion 276. The tie rod 271 extends in the vehicle width direction of a vehicle (not shown). The drive device 272 is provided at the center of the tie rod 271. The drive device 272 is, for example, a hollow motor (linear motion part), and is configured to be movable in the vehicle width direction by a ball screw or a rack & pinion for the tie rod 271. The connecting portions 274 are connected to both ends of the tie rod 271 via the links 273. The wheel drive unit 275 is attached to the connecting portion 274.

[0140] That is, the drive device 272 is connected to the wheel drive unit 275 via the link 273. The output portion of the wheel drive unit 275 is attached to the wheel portion 276. The drive device 272 swings the wheel drive unit 275 in the horizontal direction with respect to the tie rod 271 by moving the tie rod 271 in the vehicle width direction by a ball screw or a rack & pinion. Note that the drive device 272 may be a single rotating device (motor) or may be a device having a rotating device in a speed reducer. When using a device having a rotating device in a speed reducer as the drive device 272, for example, the speed reducers and rotating devices of the 1st to 9th embodiments may be adopted. The wheel drive unit 275 is, for example, an in-wheel motor that rotates the wheel portion 276 and also serves as a regenerative brake.

[0141] Here, for example, in the automotive industry, in consideration of the impact on the environment, the electrification of automobiles (EV: Electric Vehicle) is progressing. Also taking into account the automation of driving, it has become an issue to electrify driving and steering.

[0142] Thus, as shown in FIG. 24, the wheel drive unit 275 is swung horizontally with respect to the tie rod 271 by the drive device 272. With this configuration, it becomes possible to electrify the vehicle and enable autonomous driving. In addition, the steering link portion can be omitted, and it becomes possible to perform steering with steer-by-wire that does not require mechanical connection. By omitting the steering link portion, the drive device 272 can be made more compact.

[0143] Note that the technical scope of the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the spirit of the present invention.

[0144] In addition, without departing from the spirit of the present invention, it is possible to replace the components of the above-described embodiments with well-known components. Also, the above-described modified examples may be combined. [Explanation of Reference Numerals]

[0145] 10, 100, 140, 160, 170, 180, 190, 210, 220, 230, 240, 252, 300 (drive device), 11, 80, 90, 257... speed reducer, 12, 258... rotating device, 16, 102, 142, 162, 175, 222... operating mechanism, 20, 101, 223... housing cylinder (case), 26... internal gear pin (internal gear), 40... gear portion, 41, 42... gears (external gear members), 51, 171, 182, 212... crankshaft, 56... transmission gear, 70, 81... heating portion, 116... first bevel gear (drive bevel gear), 117... second bevel gear (driven bevel gear), 143... detection portion, 164a... first meshing position, 164b... second meshing position, 172... first transmission gear, 173, 181, 196, 211, 221... second transmission gears, 251... axle shaft, 254, 275... wheel drive unit, 255, 276... wheel portion, 271... tie rod, 272... drive device, 273... link, 301... sleeve, 302, 320... oil seal (seal), F0... central axis (main axis)

Claims

1. It is provided on a tie rod and includes a rotating device to which a wheel driving part provided on a wheel part is connected via a link. By moving the tie rod in the axial direction, the rotating device swings the wheel driving part horizontally with respect to the tie rod. A gear group that changes the rotation input from the rotating device and outputs it. A case that houses the gear group and has internal teeth. A sleeve provided on the case that protects a seal for sealing the case. A crankshaft that is rotatably supported inside the case in the radial direction such that the axial direction of the case becomes the rotation axis direction, and to which a rotational force is input from the rotating device. A plurality of external tooth members that have external teeth meshing with the internal teeth and that move eccentrically by the crankshaft. A speed reducer having the gear group. An operating mechanism that inputs an external rotational force to the gear group. It is provided with The operating mechanism is provided with a detection part that detects the rotation angle and torque when the rotational force is input to the gear group. The number of teeth of the internal teeth is 80 to 120. The crankshaft is a driving device with an eccentricity of 1.3 mm or less.

2. It is provided on a tie rod and includes a rotating device to which a wheel driving part provided on a wheel part is connected via a link. By moving the tie rod in the axial direction, the rotating device swings the wheel driving part horizontally with respect to the tie rod. A gear group that changes the rotation input from the rotating device and outputs it. A case that houses the gear group and has internal teeth. A sleeve provided on the case that protects a seal for sealing the case. A crankshaft that is rotatably supported inside the case in the radial direction such that the axial direction of the case becomes the rotation axis direction, and to which a rotational force is input from the rotating device. A plurality of external tooth members that have external teeth meshing with the internal teeth and that move eccentrically by the crankshaft. An operating mechanism that inputs an external rotational force to the crankshaft. It is provided with The operating mechanism A driven bevel gear that transmits a rotational force to the crankshaft. A driving bevel gear provided at a position orthogonal to the axis of the driven bevel gear and meshing with the driven bevel gear. It is provided with The driven bevel gear is switchable between a first meshing position and a second meshing position for changing the rotation direction of the driven bevel gear. The number of teeth of the internal teeth is 80 to 120. The crankshaft is a driving device with an eccentricity of 1.3 mm or less.

3. It is provided with a rotating device provided on a tie rod, and a wheel drive unit provided on a wheel portion is connected via a link. By moving the tie rod in the axial direction, the rotating device swings the wheel drive unit horizontally with respect to the tie rod. A gear group that shifts and outputs the rotation input from the rotating device. A case that houses the gear group and has internal teeth. A sleeve provided on the case that protects a seal for sealing the case. A crankshaft that is rotatably supported inside the case in the radial direction such that the axial direction of the case becomes the rotation axis direction, and a rotational force is input from the rotating device. A plurality of external tooth members that have external teeth meshing with the internal teeth and perform eccentric motion by the crankshaft. An operating mechanism for inputting an external rotational force to the crankshaft. It is provided with The crankshaft A first transmission gear to which the input from the rotating device is transmitted. A second transmission gear provided adjacent to the first transmission gear and to which the input from the operating mechanism is transmitted. It is provided with The internal teeth have 80 to 120 teeth. The crankshaft is a drive device with an eccentricity of 1.3 mm or less.

4. It is provided with a rotating device provided on a tie rod, and a wheel drive unit provided on a wheel portion is connected via a link. By moving the tie rod in the axial direction, the rotating device swings the wheel drive unit horizontally with respect to the tie rod. A gear group that shifts and outputs the rotation input from the rotating device. A case that houses the gear group and has internal teeth. A sleeve provided on the case that protects a seal for sealing the case. A crankshaft that is rotatably supported inside the case in the radial direction such that the axial direction of the case becomes the rotation axis direction, and a rotational force is input from the rotating device. A plurality of external tooth members that have external teeth meshing with the internal teeth and perform eccentric motion by the crankshaft. An operating mechanism for inputting an external rotational force to the crankshaft. It is provided with The reduction ratio of the crankshaft with respect to the rotating device is 4 to 5. The speed increase ratio of the crankshaft with respect to the operating mechanism is 4 to 5. The internal teeth have 80 to 120 teeth. The crankshaft is a drive device with an eccentricity of 1.3 mm or less.

Images