TW201937078A - Transmission device - Google Patents

Abstract

A transmission device (1) of the present invention includes a first crown gear(21), a second crown gear (22), a third crown gear (23) having a counter tooth that faces the first crown gear (21) and a counter tooth that faces the second crown gear (22), and a cam portion (30) that tilts the third crown gear (23) toward the first crown gear (21) and the second crown gear (22) so that the third crown gear (23) engages the first crown gear (21) and the third crown gear (23) engages the second crown gear (22), and makes the third crown gear (23) move wavy so that an engagement portion moves in the circumferential direction, wherein either of the first crown gear (21) and the second crown gear (22) includes a plurality of transmission gears (21A) and (21B) that have different numbers of teeth that are divided in the radial direction, and a switching mechanism (40) that switches the transmission gear to be fixed among the plurality of the transmission gears (21A) and (21B).

Description

Transmission

The present invention relates to a shifting device.
The present application claims priority on Japanese Patent Application No. 2018-027758, filed on Jan.

Patent Document 1 discloses a reduction gear device including a first crown gear, a second crown gear, and a third crown gear. The third crown gear is obliquely disposed between the first crown gear and the second crown gear with the third crown gear meshing with the first crown gear and the third crown gear meshing with the second crown gear. The third crown gear is rotatably supported by an input shaft having a curved portion. The input shaft oscillates the third crown gear in such a manner that a portion where the first crown gear meshes with the third crown gear and a portion where the third crown gear meshes with the second crown gear move in the circumferential direction.

The first crown gear is fixed to the housing, and the second crown gear is coupled to the output shaft. The amount of difference in the number of teeth of the third crown gear to the relative rotation of the first crown gear by the wave motion of the third crown gear when the input shaft is rotated. Further, the amount of difference in the number of teeth of the second crown gear to the relative rotation of the third crown gear is caused by the wave motion of the third crown gear. The rotation speed of the second crown gear is obtained by accumulating the relative rotation speed of the third crown gear with respect to the first crown gear and the relative rotation speed of the second crown gear with respect to the third crown gear. If the two sets of gears (the first crown gear and the third crown gear, the third crown gear and the second crown gear) are rotated in a direction in which they cancel each other, a larger reduction ratio can be obtained, and if they rotate in the direction of mutual encouragement, A smaller reduction ratio can be obtained.
[Previous Technical Literature]
[Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open No. 60-4647

[The problem that the invention wants to solve]

However, the above-described speed reducer has a smaller size in the radial direction than a speed reducer such as a normal spur gear, and is expected to be introduced into a joint portion of an industrial robot. In the case where the industrial robot is required to perform various operations, for example, when the conveyed object is lifted, it is preferable to be able to move at a low speed and a large torque, and it is preferable to carry out the removal of the next conveyed object after the conveyed object is placed. Move at high speed and low torque. However, in the above-described reduction gear transmission, since the switching technique of the reduction ratio corresponding to such a request has not yet been established, it has become one of practical problems.

The present invention provides a shifting device that is miniaturized and can switch a reduction ratio.
[Technical means to solve the problem]

According to a first aspect of the present invention, a shifting device includes: a first crown gear; a second crown gear; a third crown gear having a back-aligned opposing tooth opposite the first crown gear and the second a cam gear opposite to the tooth; a cam portion, wherein the third crown gear is engaged with the first crown gear, and the third crown gear is engaged with the second crown gear to make the third crown gear The first crown gear and the second crown gear are inclined, and the third crown gear is fluctuated in such a manner that the meshing portion moves in a circumferential direction; and any one of the first crown gear and the second crown gear has a diameter a plurality of shifting gears having different numbers of teeth to be divided; and a switching mechanism for switching the fixed shifting gear from among the plurality of shifting gears.
[Effects of the Invention]

According to the above-described shifting device, it is possible to downsize and switch the reduction ratio.

Hereinafter, a transmission device according to an embodiment of the present invention will be described with reference to the drawings.

(First embodiment)
Fig. 1 is a perspective view of a transmission 1 according to a first embodiment of the present invention. Fig. 2 is a longitudinal sectional view showing a transmission 1 according to the first embodiment of the present invention.
As shown in FIG. 1, the speed change device 1 includes a bottomed cylindrical casing 10, and the motor 2 is attached to the bottom of the casing 10. As shown in Fig. 2, the central axis of the bottomed cylindrical casing 10 coincides with the axis L of the rotating shaft 2a of the motor 2. Hereinafter, the direction in which the axis L extends is referred to as an axial direction, the direction orthogonal to the axis L is referred to as a radial direction, and the direction in which the axis L is rotated is referred to as a circumferential direction.

As shown in FIG. 2, inside the casing 10, a first crown gear 21, a second crown gear 22, a third crown gear 23, a cam portion 30, and a switching mechanism 40 to be described later are housed. The rotating shaft 2a of the motor 2 is connected to the cam portion 30 via a shaft joint 39, and the cam portion 30 is inclined to support the third crown gear 23. When the cam portion 30 rotates, the third crown gear 23 meshing with the first crown gear 21 fluctuates (otherwise, the wave motion is also referred to as a precessional motion), and the rotational speed of the rotating shaft 2a is decelerated while the second crown gear 22 ( Output gear) rotates. Further, the reduction ratio is determined based on the number of teeth of the first crown gear 21, the second crown gear 22, and the third crown gear 23 (described later).

The casing 10 includes a mounting plate 11 , a first cylindrical portion 12 , a second cylindrical portion 13 , and a pressing plate 14 . A motor 2 is attached to the mounting plate 11 via a bolt 3. The mounting plate 11 is a disk member that forms the bottom of the casing 10, and the rotating shaft 2a of the motor 2 is inserted through the center portion thereof. The first cylindrical portion 12 is connected to a surface opposite to the mounting surface of the motor 2 of the mounting plate 11 via a bolt (not shown). A switching mechanism 40 to be described later is housed inside the first cylindrical portion 12.

The second cylindrical portion 13 is connected to the first cylindrical portion 12 in the axial direction via a bolt 17 . A step is formed on the inner peripheral side of the connecting portion between the first cylindrical portion 12 and the second cylindrical portion 13, and the bearing 15 is supported. The bearing 15 rotatably supports the second shift gear 21B, which will be described later, of the first crown gear 21 about the axis L. The first crown gear 21, the second crown gear 22, the third crown gear 23, and the cam portion 30 are housed inside the second cylindrical portion 13.

The pressing plate 14 is an annular plate body and is connected to the upper end surface of the second cylindrical portion 13 via a bolt 18. A step is formed on the inner peripheral side of the connecting portion between the second cylindrical portion 13 and the pressing plate 14, and the bearing 16 is supported. The bearing 16 rotatably supports the second crown gear 22 about the axis L. The upper end surface of the second crown gear 22 protrudes outward in the axial direction from the pressing plate 14, and a mounting hole 22b for mounting a rotating object is formed on the upper end surface thereof.

Fig. 3 is an enlarged view of a main portion including the first crown gear 21, the second crown gear 22, and the third crown gear 23 according to the first embodiment of the present invention. Fig. 4 is a perspective view of the first crown gear 21 of the first embodiment of the present invention. Fig. 5 is a front elevational view showing the first crown gear 21, the second crown gear 22, and the third crown gear 23 according to the first embodiment of the present invention.
On the inner side of the casing 10, as shown in FIG. 3, the annular first crown gear 21 and the annular second crown gear 22 are disposed coaxially with the axis L. A third crown gear 23 is disposed between the first crown gear 21 and the second crown gear 22.

The first crown gear 21 has opposing teeth 21a, 21b on the side opposite to the third crown gear 23. The second crown gear 22 has a counter tooth 22a on the side opposite to the third crown gear 23. The third crown gear 23 has a counter-aligning tooth 23a opposite to the first crown gear 21 and a counter tooth 23b opposed to the second crown gear 22, which are aligned on the back side. The third crown gear 23 is inclined by an angle α with respect to a plane orthogonal to the axis L. By tilting the third crown gear 23, as shown in FIG. 5, the third crown gear 23 is engaged with the first crown gear 21 at one of the opposing teeth 23a in the circumferential direction, and its opposite tooth 23b is in the circumferential direction. The portion is engaged with the second crown gear 22.

The third crown gear 23 is supported by the cam portion 30 as shown in FIG. The cam portion 30 includes a first cam 31 that extends toward the first crown gear 21 side from the third crown gear 23, and a second cam 32 that extends toward the second crown gear 22 side from the third crown gear 23. A bearing 35 that supports the first crown gear 21 and the first shift gear 21A described later is disposed on the outer peripheral side of the first cam 31. Further, a bearing 36 that supports the second crown gear 22 is disposed on the outer peripheral side of the second cam 32.
The first cam 31 and the second cam 32 are axially connected via a bolt 34.

The third crown gear 23 is disposed at a connection portion between the first cam 31 and the second cam 32. Specifically, the first inclined surface 31a and the second inclined surface 32a which are parallel to each other and are inclined with respect to the axis L are formed on the outer peripheral side of the connecting portion between the first cam 31 and the second cam 32. Similarly to the third crown gear 23, the first inclined surface 31a and the second inclined surface 32a are inclined by an angle α with respect to a plane orthogonal to the axis L.

A rolling element 33 (ball or the like) is interposed between the first cam 31 and the third crown gear 23 . The first inclined surface 31a is formed with a rolling element rolling groove 31b in which a cross section through which the rolling elements 33 roll is substantially circular. In the third crown gear 23, a rolling element rolling groove 23c having a substantially circular cross section is formed in a portion opposed to the rolling element rolling groove 31b. The rolling element rolling grooves 23c and 31b are formed in an annular shape around the axis L, and a plurality of rolling elements 33 can be arranged in an endless cycle.

Further, a rolling element 33 (ball or the like) is interposed between the second cam 32 and the third crown gear 23. On the second inclined surface 32a, a rolling element rolling groove 32b in which a cross section through which the rolling elements 33 roll is observed is formed into a substantially circular shape. In the third crown gear 23, a rolling element rolling groove 23d having a substantially circular cross section is formed at a portion opposed to the rolling element rolling groove 32b. The rolling element rolling grooves 23d and 32b are formed in a ring shape around the axis L, and the plurality of rolling elements 33 can be arranged in an endless cycle.

Further, the rolling elements 33 may be held by a retainer for preventing fall-off which is not shown. Further, it is preferable that the rolling element 33 is preloaded so that the third crown gear 23 sandwiched between the first cam 31 and the second cam 32 does not generate a backlash. For example, the first cam 31 and the second cam 32 are fastened in the axial direction by the bolts 34, and the rolling elements 33 can be imparted between the rolling element rolling grooves 23c and 31b and the rolling element rolling grooves 23d and 32b. Preloading.

Referring back to FIG. 2, on the side opposite to the first cam 31 of the second cam 32, the shaft coupling portion 37 is connected via a bolt 38. A step is formed on the outer peripheral side of the connecting portion between the second cam 32 and the shaft coupling portion 37, and the above-described bearing 35 is supported. The shaft coupling portion 37 has a coupling shaft 37a extending along the axis L, and the coupling shaft 37a is connected to the rotation shaft 2a of the motor 2 via a shaft joint 39.

As shown in FIGS. 3 and 4, the first crown gear 21 has a first shift gear 21A and a second shift gear 21B which are divided in the radial direction. Each of the first shift gear 21A and the second shift gear 21B is formed in an annular shape and disposed coaxially with the axis L. In the present embodiment, the first shift gear 21A is disposed radially inward of the second shift gear 21B. The first shift gear 21A has a counter tooth 21a on the side opposite to the third crown gear 23. Further, the second shift gear 21B has the opposing teeth 21b having different numbers of teeth from the opposing teeth 21a on the side opposite to the third crown gear 23.

Returning to FIG. 2, the first shifting gear 21A and the second shifting gear 21B are supported by the switching mechanism 40. The switching mechanism 40 fixes either of the first shift gear 21A and the second shift gear 21B with respect to the casing 10 in accordance with the rotation direction. Specifically, the switching mechanism 40 has a first one-way clutch 41 that rotates the first shifting gear 21A only in one direction (for example, clockwise centered on the axis L); and a second one-way clutch 42 that makes The second shifting gear 21B rotates only in one direction opposite to the first shifting gear 21A (for example, counterclockwise about the axis L).

For example, in the case of clockwise rotation centered on the axis L, the first shifting gear 21A can be freely rotated in the direction by the first one-way clutch 41, and the second shifting gear 21B is The rotation of the clutch 42 is restricted in this direction, so that it is fixed (stopped) with respect to the casing 10. Further, for example, in the case of counterclockwise rotation centered on the axis, the second shifting gear 21B is freely rotatable in the direction thereof by the second one-way clutch 42, and on the other hand, the first shifting gear 21A is first The one-way clutch 41 is restricted in its direction of rotation and fixed (stopped) with respect to the housing 10.

The first one-way clutch 41 and the second one-way clutch 42 are supported by the outer circumferential surface of the cylindrical support member 43 connected to the mounting plate 11 via a bolt (not shown) via the spacer 44. The cylindrical support member 43 is formed with a through hole 43a through which the rotating shaft 2a, the connecting shaft 37a, and the shaft joint 39 are disposed. Further, on the side of the mounting plate 11 of the cylindrical support member 43, the flange portion 43b of the second one-way clutch 42 is supported to extend radially outward. A pressing plate 45 that sandwiches the first one-way clutch 41, the spacer 44, and the second one-way clutch 42 in the axial direction between the flange portion 43b and the flange portion 43b is connected to the upper end surface of the cylinder supporting member 43 via a bolt 46. .

The first one-way clutch 41 is connected to the first shift gear 21A via the first connecting member 47. The first connecting member 47 is a cylindrical member whose upper end portion is reduced in diameter by the difference in diameter, and the end portion of the reduced diameter is connected to the bottom of the first shifting gear 21A via a bolt 48. A step is formed on the inner peripheral side of the connection portion between the first transfer gear 21A and the first connecting member 47 to support the above-described bearing 35.

The second one-way clutch 42 is connected to the second shift gear 21B via the second connecting member 49. The second connecting member 49 has a bottomed cylindrical first member 49A having an inner diameter larger than the outer diameter of the first connecting member 47, and a second member 49B connected to the upper end portion of the first member 49A via a bolt 50.

The second member 49B is an auxiliary stepped cylindrical member whose upper end portion is reduced in diameter, and an inner diameter of the upper end portion of the reduced diameter is larger than an outer diameter of the upper end portion of the reduced diameter of the first connecting member 47, and is smaller than the first connecting member 47. The outer diameter of the end below the diameter is not reduced. The upper end portion of the second member 49B is connected to the bottom of the second shift gear 21B via a bolt 51. A step is formed on the outer peripheral side of the connecting portion between the second transfer gear 21B and the second connecting member 49 (second member 49B) to support the above-described bearing 15.

According to the above-described shifting device 1, when the rotating shaft 2a of the motor 2 is rotated, the third crown gear 23 sandwiched between the first cam 31 and the second cam 32 is fluctuating (that is, the third crown gear 23 is precessed) motion). Along with the wave motion of the third crown gear 23, the meshing portion of the first crown gear 21 and the third crown gear 23, and the meshing portion of the third crown gear 23 and the second crown gear 22 move in the circumferential direction. The meshing portion of the first crown gear 21 and the third crown gear 23 and the meshing portion of the third crown gear 23 and the second crown gear 22 have a positional relationship symmetrical with respect to the axis L from the axial direction, when the meshing is at When moving in the circumferential direction, the third crown gear 23 is rocked left and right like a seesaw in the cross section shown in FIG.

Along with the wave motion of the third crown gear 23, the third crown gear 23 rotates relative to the first crown gear 21 relative to the axis L by the amount of the difference in the number of teeth. Moreover, the second crown gear 22 rotates relative to the third crown gear 23 relative to the axis L by the amount of the difference in the number of teeth. The rotational speed of the second crown gear 22 is obtained by accumulating the relative rotational speed of the third crown gear 23 with respect to the first crown gear 21 and the rotational speed of the second crown gear 22 with respect to the third crown gear 23. If the gears of the two sets (the first crown gear 21 and the third crown gear 23, the third crown gear 23 and the second crown gear 22) are rotated in a direction canceling each other, a larger reduction ratio can be obtained, if it is equal to Rotate in the direction of each other to obtain a smaller reduction ratio.

If the first crown wheel 21 of the set of teeth 21a of the gear 21b to the number of teeth Z _1, the first crown gear and the third gear 23 engages the crown 21 of the teeth 23a is set to the number of teeth Z _2, The number of teeth of the opposing teeth 23b of the third crown gear 23 meshing with the second crown gear 22 is Z ₃ , and the number of teeth of the opposing teeth 22a of the second crown gear 22 is Z ₄ , and the reduction ratio GR is based on the following Formula (1) is given.

[Number 1]

For example, if Z ₁ =40, Z ₂ =40, Z ₃ =43, and Z ₄ =42, the reduction ratio GR is -1/42. On the other hand, when the number of teeth of Z ₁ is decreased by one and Z ₁ =39, Z ₂ =40, Z ₃ =43, and Z ₄ =42, the reduction ratio GR is 1/560. Thus, if Z ₁ = Z ₂ , the first crown gear 21 only exerts the anti-rotation action of the third crown gear 23, and the reduction ratio depends on the second crown gear 22. This kind of action is called coarse motion. Further, when Z ₁ ≠ Z _2, the first crown gear 21 also play a role in the reduction, the reduction ratio depends on the first crown gear 21 and the second crown gear 22, the large reduction ratio can be obtained. This action is called micromotion. In the present embodiment, the first shift gear 21A has the number of teeth of Z ₁ = 39 in the above-described example, and the second shift gear 21B has the number of teeth of Z ₁ = 40.

Fig. 6 is an explanatory view for explaining the coarse motion of the transmission 1 according to the first embodiment of the present invention.
As shown in FIG. 6, when the shifting device 1 is coarsely moved, the first shifting gear 21A is freely rotated clockwise about the axis L by the first one-way clutch 41 (refer to FIG. 2), and the second shifting gear 21B is on the other hand. It is fixed (not rotated) by the second one-way clutch 42 (refer to FIG. 2). At this time, the first shift gear 21A only rotates in conjunction with the third crown gear 23, and does not have a special effect. Therefore, in Fig. 6, it is represented by a blank.

On the other hand, the fixed second shifting gear 21B contributes to the wave motion of the third crown gear 23 by meshing with the third crown gear 23. Therefore, in Fig. 6, it is represented by dots. The second shift gear 21B has the counter teeth 21b having the same number of teeth (Z ₁ = Z ₂ ) as the opposing teeth 23a of the third crown gear 23. The third crown gear 23 is relatively rotatably moved about the axis L with respect to the second shift gear 21B along with the wave motion. Therefore, if there is no difference in the number of teeth, the third gear 23 still fluctuates but does not rotate. Thus, the second shift gear 21B only has the function of the rotation of the third crown gear 23, and since the reduction ratio is determined by the second crown gear 22, the reduction ratio becomes small, and the second crown gear 22 is coarsely moved at a high speed and low torque. Rotate.

Fig. 7 is an explanatory view for explaining the fine movement of the transmission 1 according to the first embodiment of the present invention.
As shown in FIG. 7, when the shifting device 1 is slightly moved, the second shifting gear 21B is freely rotated counterclockwise about the axis L by the second one-way clutch 42 (refer to FIG. 2), and the first shifting gear 21A is on the other hand. It is fixed (not rotated) by the first one-way clutch 41 (refer to FIG. 2). At this time, the second shift gear 21B rotates only together with the third crown gear 23, and does not have a special effect. Therefore, in Fig. 7, it is represented by a blank.

On the other hand, the fixed first shifting gear 21A contributes to the wave motion of the third crown gear 23 by meshing with the third crown gear 23. Therefore, in Fig. 7, it is represented by dots. The first shift gear 21A has a counter tooth 21a different from the counter tooth 23a of the third crown gear 23 by a different number of teeth (Z ₁ ≠Z ₂ ). The third crown gear 23 is rotated relative to the second shift gear 21B about the axis L with the fluctuation of the gear amount, and the third gear 23 rotates together with the wave motion. In this way, since the first shift gear 21A only has the action of the rotation and deceleration of the third crown gear 23, the reduction ratio depends on the first shift gear 21A and the second crown gear 22, so that the reduction ratio becomes large, and the second crown gear 22 Micro-rotation at low speed and high torque.

As described above, according to the above-described embodiment, the first crown gear 21, the second crown gear 22, and the third crown gear 23 have the back alignment and the first crown gear 21 facing each other. The teeth 23a and the opposing teeth 23b opposite to the second crown gear 22; and the cam portion 30 meshing with the first crown gear 21 with the third crown gear 23 and the third crown gear 23 meshing with the second crown gear 22 The third crown gear 23 is inclined with respect to the first crown gear 21 and the second crown gear 22, and the third crown gear 23 is wave-moved in such a manner that the meshing portion moves in the circumferential direction; the first crown gear 21 and the second The crown gear 22 has a plurality of shift gears 21A and 21B having different numbers of teeth divided in the radial direction, and has a switching mechanism 40 that switches the fixed shift gear from among the plurality of shift gears 21A and 21B. A device that maintains a small radial direction constitutes and switches the reduction ratio.

Further, since the switching mechanism 40 of the present embodiment switches the fixed shift gears 21A and 21B in accordance with the rotation direction, the speed reduction ratio can be changed, for example, in the forward and reverse strokes of the industrial robot (forward rotation and reverse rotation of the motor 2). For example, when the industrial robot lifts the transported object by winding the rope through the transmission device 1, the vehicle can be moved at a low speed and with high torque, and when the transported object is lifted, and the rope is retracted to pick up the next transported object, It can be moved at high speed and low torque, so it can improve the working efficiency of industrial robots and improve productivity.

Further, in the present embodiment, the switching mechanism 40 has the first one-way clutch 41 that rotates the first transmission gear 21A in only one direction, and the second transmission gear 21B that is only opposite to the first transmission gear 21A. Since the second one-way clutch 42 rotates in one direction, it is not necessary to use an electric actuator or the like, and the speed reduction ratio can be switched without a power source.

Further, as in the present embodiment, as long as the second shift gear 21B includes the opposing teeth 21b having the same number of teeth as the opposing teeth 23a of the third crown gear 23, the rotation of the third crown gear 23 can be fixed, and the second crown can be The gear 22 determines the reduction ratio, so that a smaller reduction ratio can be easily obtained.

(Second embodiment)
Next, a second embodiment of the present invention will be described. In the following description, the same or equivalent components as those in the above-described embodiments are denoted by the same reference numerals, and the description thereof will be omitted or omitted.

Fig. 8 is a longitudinal sectional view showing a transmission 1A according to a second embodiment of the present invention.
The transmission 1A of the second embodiment includes a switching mechanism 40A having a wedge portion 41A that is inserted into a gap between the first transmission gear 21A and the second transmission gear 21B, and a movable portion 42A that fixes the wedge portion 41A. The first fixed position of the first shifting gear 21A and the second fixed position of the fixed second shifting gear 21B are movable.

The wedge portion 41A is a cylindrical member inserted into the annular gap between the first transfer gear 21A and the second transfer gear 21B, and an inclined portion 43A having an enlarged diameter is formed at the insertion end thereof. In the outer peripheral surface of the first shift gear 21A of the second embodiment, an inclined surface 21a1 (tapered surface) inclined with respect to the axis L like the inclined portion 43A is formed. Further, on the inner circumferential surface of the second shift gear 21B, an inclined surface 21b1 (tapered surface) inclined with respect to the axis L similarly to the inclined portion 43A is formed.

The wedge portion 41A is movable in the axial direction by the movable portion 42A. The movable portion 42A can move the output shaft connected to the wedge portion 41A in the axial direction, for example, in an actuator or the like fixed to the casing 10 (not shown) in Fig. 8 . The movable portion 42A allows the wedge portion 41A to be fixed at the first fixed position P1 of the first shift gear 21A (indicated by a two-dot chain line in FIG. 8) and the second fixed position P2 of the fixed second shift gear 21B (FIG. 8). Moved in the middle line).

Fig. 9 is an explanatory view for explaining the coarse movement of the transmission 1 according to the second embodiment of the present invention.
As shown in FIG. 9, when the shifting device 1 is coarsely moved, the movable portion 42A moves the wedge portion 41A to the second fixed position P2. When the wedge portion 41A moves to the second fixed position P2, the inclined portion 43A comes into contact with the inclined surface 21b1 of the second shift gear 21B, and the second shift gear 21B is fixed, and the first shift gear 21A is freely rotatable. The fixed second shifting gear 21B contributes to the wave motion of the third crown gear 23 by meshing with the third crown gear 23, but because of the difference in the number of teeth, the deceleration is relatively small as described above, and the second crown gear 22 is high speed. And coarse rotation with low torque.

Fig. 10 is an explanatory view for explaining the fretting of the transmission 1 according to the second embodiment of the present invention.
As shown in FIG. 10, when the shifting device 1 is slightly moved, the movable portion 42A moves the wedge portion 41A to the first fixed position P1. When the wedge portion 41A moves to the first fixed position P1, the inclined portion 43A comes into contact with the inclined surface 21a1 of the first shift gear 21A, and the first shift gear 21A is fixed, and the second shift gear 21B is free to rotate. The fixed first shifting gear 21A is meshed with the third crown gear 23 to facilitate the wave motion and rotation with the third crown gear 23, which is relatively large as described above, and the second crown gear 22 has a low speed and a high torque. Jog rotation.

According to the second embodiment described above, in addition to the operation and effect similar to those of the first embodiment, the reduction ratio can be switched without switching the rotation direction. Further, since the fixed gears 21A and 21B can be switched by moving the wedge portion 41A inserted into the gap between the first shift gear 21A and the second shift gear 21B, the first shift gear 21A and the second shift gear are used. Each of 21B is provided with a fixing/unfixing mechanism, the number of parts is reduced, and the device configuration is also miniaturized.

Further, in the present embodiment, the wedge portion 41A has the inclined portion 43A that can be abutted against the first shift gear 21A and the second shift gear 21B by the axial movement, so that it can be moved only in one direction of the axial direction. The fixed shift gears 21A, 21B are simply switched.

(Third embodiment)
Next, a third embodiment of the present invention will be described. In the following description, the same or equivalent components as those in the above-described embodiments are denoted by the same reference numerals, and the description thereof will be omitted or omitted.

Fig. 11 is a longitudinal sectional view showing a transmission 1B according to a third embodiment of the present invention.
The transmission 1B of the third embodiment includes a motor 2B that rotates the cam portion 30 inside the radial direction of the cam portion 30.

The motor 2B is an outer rotor type motor. The motor 2B includes a stator 100 for providing a plurality of coils 102 and a rotor 110 for providing a plurality of permanent magnets 111. Alternatively, the coil 102 may be disposed on the outer rotor 110, and the permanent magnet 111 may be disposed on the stator 100.

The stator 100 has a stator core 101 and a coil 102 supported by the stator core 101. The stator core 101 is formed in a cylindrical shape extending along the axis L. On the circumferential surface of the stator core 101, a plurality of tooth portions 101a (salient poles) extending outward in the radial direction are formed. The coil 102 is wound around the tooth portion 101a.

The lower end portion 101b of the stator core 101 is fixed to the top of the cylindrical support member 43B which is integral with the mounting plate 11 of the casing 10. The cylindrical support member 43B extends upward from the central portion of the upper surface of the mounting plate 11 along the axis L. The cylindrical supporting member 43B is a solid cylindrical support member 43 (see FIG. 2) described above, and the other configuration is the same as that of the cylindrical supporting member 43.

The outer rotor 110 has a permanent magnet 111 and a rotor core 112 that supports the permanent magnet 111. The permanent magnet 111 has a gap in the radial direction opposed to the tooth portion 101a of the stator core 101. The permanent magnet 111 is fixed to the inner circumferential surface of the through hole 112a that penetrates the center of the rotor core 112 in the axial direction.

The rotor core 112 is integral with the above-described cam portion 30. In other words, it can be said that the rotor core 112 forms the cam portion 30. Similarly to the above-described cam portion 30, the rotor core 112 is rotatably supported around the axis L via the bearing 35 and the bearing 36. Further, the rotor core 112 supports the third crown gear 23 obliquely with respect to a plane orthogonal to the axis L via the rolling elements 33. Further, the rotor core 112 may be divided into the first cam 31 and the second cam 32 in the same manner as the above-described cam portion 30.

According to the above-described shifting device 1B, when the rotor 110 is rotated outside the motor 2B, the third crown gear 23 supported by the rotor core 112 (the cam portion 30) fluctuates (i.e., the third crown gear 23 is moved). Along with the wave motion of the third crown gear 23, the meshing portion of the first crown gear 21 and the third crown gear 23, and the meshing portion of the third crown gear 23 and the second crown gear 22 move in the circumferential direction. Along with the wave motion of the third crown gear 23, the third crown gear 23 rotates relative to the first crown gear 21 relative to the axis L by the amount of the difference in the number of teeth. Moreover, the second crown gear 22 rotates relative to the third crown gear 23 relative to the axis L by the amount of the difference in the number of teeth. That is, the same reduction ratio as that of the above embodiment can be obtained.

According to the third embodiment, in addition to the operational effects similar to those of the above-described embodiment, the motor 2B that rotates the cam portion 30 is provided inside the radial direction of the cam portion 30, so that the shifting is performed, for example, as shown in FIG. The size of the axial direction of the shifting device 1B is reduced in size compared to the device 1.

Since the motor 2B is further disposed inside the radial direction of at least one of the first crown gear 21, the second crown gear 22, and the third crown gear 23 (all in the example shown in FIG. 11), the motor 2B is disposed. The axial position overlapping with the first crown gear 21, the second crown gear 22, and the third crown gear 23 contributes to downsizing of the axial direction of the shifting device 1B.

Further, since the motor 2B includes the rotor 110 integrated with the cam portion 30, it is not necessary to be divided into other components that are divided into the cam portion 30 and the outer rotor 110 in the radial direction, and contributes to the small size of the radial direction of the transmission device 1B. Chemical.

(Fourth embodiment)
Next, a fourth embodiment of the present invention will be described. In the following description, the same or equivalent components as those in the above-described embodiments are denoted by the same reference numerals, and the description thereof will be omitted or omitted.

Fig. 12 is a longitudinal sectional view showing a transmission 1C according to a fourth embodiment of the present invention.
The transmission 1C of the fourth embodiment includes a motor 2C that rotates the cam portion 30 inside the radial direction of the cam portion 30. Further, the transmission 1C of the fourth embodiment is provided with a third crown gear 23C that is supported by the cam portion 30 on the side opposite to the first crown gear 21. Further, the transmission 1C of the fourth embodiment includes a second crown gear 22C that meshes with the third crown gear 23C on the same side as the first crown gear 21. In other words, the third crown gear 23C of the fourth embodiment has the opposing teeth 23a facing the first crown gear 21 and the opposing teeth 23b facing the second crown gear 22C on the same side in the axial direction.

The third crown gear 23C has the opposing teeth 23b on the radially outer side of the opposing teeth 23a. An annular groove 23f is formed between the opposing tooth 23a and the opposing tooth 23b. The second crown gear 22C that meshes with the opposing teeth 23b of the third crown gear 23C is disposed on the radially outer side of the first crown gear 21. In other words, the first crown gear 21 is disposed inside the radial direction of the third crown gear 23C. The third crown gear 23C is rotatably supported about the axis L via the above-described bearing 15.

An opposite side of the opposing teeth 23a of the third crown gear 23C and the surface on which the opposing teeth 23b are formed is an inclined surface 23e inclined with respect to a plane orthogonal to the axis L. The above-described rolling element rolling groove 23c is formed in the peripheral portion of the inclined surface 23e. The rolling element rolling groove 23c faces the rolling element rolling groove 32c formed in the cam portion 30 in the axial direction. The rolling element rolling groove 32c is formed in a peripheral portion of the inclined surface 212b formed in parallel with the inclined surface 23e. Between the rolling element rolling groove 23c and the rolling element rolling groove 32c, a plurality of rolling elements 33 are arranged in an infinite loop around the axis L.

The cam portion 30 is disposed on the inclined surface 23e side of the third crown gear 23C (opposite to the surface on which the opposing teeth 23a and the opposing teeth 23b are formed). Further, the cam portion 30 is formed in a disk shape having substantially the same diameter as the third crown gear 23C. In other words, the cam portion 30 is not disposed inside the radial direction of the third crown gear 23C, and is not disposed inside the radial direction of the first crown gear 21 and the second crown gear 22C. The cam portion 30 is rotatably supported around the axis L via a bearing 16 (see FIG. 2) supported by the casing 10 (not shown in FIG.

A motor 2C that rotates the cam portion 30 is disposed inside the radial direction of the cam portion 30. The motor 2C is a rotor type motor similar to the motor 3B of the third embodiment described above. The motor 2C includes a stator 200 for providing a plurality of coils 202, and a rotor 210 for providing a plurality of permanent magnets 211. Alternatively, the coil 202 may be disposed on the outer rotor 210, and the permanent magnet 211 may be disposed on the stator 200.

The stator 200 has a stator core 201 and a coil 202 supported by the stator core 201. The stator core 201 is formed in an annular shape coaxial with the axis L. On the circumferential surface of the stator core 201, a plurality of stators 201a (salient poles) extending outward in the radial direction are formed. A coil 202 is wound around the stator 201a.

A second cylindrical support member 220 having a step 222 formed on the outer peripheral surface is fitted to the inner side in the radial direction of the stator core 201. The second cylindrical support member 220 is fixed to the upper end portion of the above-described cylindrical support member 43 via a bolt 46. The second cylindrical support member 220 extends upward from the upper end portion of the cylindrical support member 43 along the axis L. Further, the lower end portion of the second cylindrical support member 220 is a flange 221 which is expanded in the radial direction.

The flange 221 extends from the upper end portion of the cylindrical support member 43 to the radially outer side, and abuts against the bearing 35 in the axial direction. The bearing 35 is supported by a cylindrical sleeve 230 that is externally inserted into the cylindrical support member 43. On the outer circumferential surface of the sleeve 230, a step 231 of the bearing 35 in the axial direction is formed. Further, the lower end portion of the sleeve 230 abuts against the first one-way clutch 41 in the axial direction. The flange 221 sandwiches the bearing 35 and the sleeve 230 in the axial direction, and has the same function as the above-described pressing plate 45. The first one-way clutch 41 and the spacer 44 are axially sandwiched via the sleeve 230. The second one-way clutch 42.

The outer rotor 210 has a permanent magnet 211 and a rotor core 212 that supports the permanent magnet 211. The permanent magnet 211 is opposed to the stator 201a of the stator core 201 by a gap in the radial direction. The permanent magnet 211 is fixed to the inner circumferential surface of the through hole 212a that penetrates the center of the rotor core 212 in the axial direction.

The rotor core 212 is integral with the above-described cam portion 30. In other words, it can also be said that the rotor core 212 forms the cam portion 30. Since the configuration of the rotor core 212 is the same as that of the above-described cam portion 30, the description thereof will be omitted.

According to the above-described shifting device 1C, when the rotor 210 is rotated outside the motor 2C, the third crown gear 23C supported by the rotor core 212 (the cam portion 30) fluctuates (i.e., the third crown gear 23 comes into motion). Along with the wave motion of the third crown gear 23C, the meshing portion of the first crown gear 21 and the third crown gear 23C and the meshing portion of the third crown gear 23 and the second crown gear 22 move in the circumferential direction. Along with the wave motion of the third crown gear 23C, the third crown gear 23C is relatively rotated relative to the first crown gear 21 about the axis L by the amount of the difference in the number of teeth. Further, the second crown gear 22C is relatively rotatable relative to the third crown gear 23C about the axis L by the amount of the difference in the number of teeth. That is, the same reduction ratio as that of the above embodiment can be obtained.

According to the fourth embodiment, the motor 2C that rotates the cam portion 30 is provided on the inner side in the radial direction of the cam portion 30, in addition to the operation and effect similar to the above-described embodiment, and thus the third embodiment is the same as the third embodiment. The size of the axial direction of the shifting device 1C is miniaturized.

Further, in the present embodiment, since the motor 2B includes the rotor 210 integrated with the cam portion 30, it is not necessary to be divided into other components that are divided into the cam portion 30 and the outer rotor 210 in the radial direction, and contributes to the shifting device 1C. The size of the radial is miniaturized.

Further, in the present embodiment, the second crown gear 22C that is meshed with the third crown gear 23C is provided on the same side as the first crown gear 21, so that it can be extracted from the same side as the first crown gear 21 (shift gear). Output.

The preferred embodiments of the present invention have been described above with reference to the drawings, but the present invention is not limited to the embodiments described above. The shapes and combinations of the constituent members disclosed in the above-described embodiments are merely examples, and various modifications can be made based on design requirements and the like without departing from the gist of the invention.

For example, in the above-described embodiment, the configuration in which the first crown gear 21 has the two shift gears 21A and 21B will be described. However, the first crown gear 21 may have three or more shift gears having different numbers of teeth.
Further, the plurality of shifting gears may be located not on the side of the first crown gear 21 but on the side of the second crown gear 22 (may also be configured to switch the reduction ratio on the output side).

Further, for example, in the first embodiment described above, a configuration in which a one-way clutch without a power source is used as the switching mechanism 40 will be described, but an electric one-way clutch may be used. Further, the electric one-way clutch may be disposed, for example, between the first shift gear 21A and the second shift gear 21B, and may be arranged to rotate one of the shift gears to fix the other shift gear.
[Industrial availability]

According to the above-described shifting device, it is possible to downsize and switch the reduction ratio.

1‧‧‧Transmission device

1A‧‧‧Transmission

1B‧‧‧Transmission

1C‧‧·Transmission

2‧‧‧Motor

2a‧‧‧Rotary axis

2B‧‧‧Motor

2C‧‧‧Motor

3‧‧‧ bolt

10‧‧‧shell

11‧‧‧Installation board

12‧‧‧First cylindrical part

13‧‧‧Second cylinder

14‧‧‧ Pressing plate

15‧‧‧ bearing

16‧‧‧ bearing

17‧‧‧ bolt

18‧‧‧ bolt

21‧‧‧1st crown gear

21A‧‧‧First shifting gear

21a‧‧‧ opposite teeth

21a1‧‧‧ sloped surface

21B‧‧‧Second gear

21b‧‧‧ opposite teeth

21b1‧‧‧ sloped surface

22‧‧‧second crown gear

22a‧‧‧ opposite teeth

22b‧‧‧Mounting holes

22C‧‧‧second crown gear

23‧‧‧ Third crown gear

23a‧‧‧ opposite teeth

23b‧‧‧ opposite teeth

23c‧‧‧ rolling body rolling groove

23C‧‧‧ rolling body rolling groove

23d‧‧‧ rolling body rolling groove

23e‧‧‧ sloped surface

23f‧‧‧ring groove

30‧‧‧Cam Department

31‧‧‧First Cam

31a‧‧‧First inclined surface

31b‧‧‧ rolling body rolling groove

32‧‧‧second cam

32a‧‧‧Second inclined surface

32b‧‧‧ rolling body rolling groove

32c‧‧‧ rolling body rolling groove

33‧‧‧ rolling elements

34‧‧‧Bolts

35‧‧‧ bearing

36‧‧‧ Bearing

37‧‧‧Axis joint

37a‧‧‧Connected shaft

38‧‧‧ bolt

39‧‧‧ shaft joint

40‧‧‧Switching mechanism

40A‧‧‧Switching mechanism

41A‧‧‧Wedge

41‧‧‧First one-way clutch

42‧‧‧Second one-way clutch

42A‧‧‧movable department

43‧‧‧Cylinder support member

43A‧‧‧ inclined section

43B‧‧‧Cylindrical support member

43a‧‧‧through hole

43b‧‧‧Flange

44‧‧‧ Spacer

45‧‧‧ Press plate

46‧‧‧Bolts

47‧‧‧First connecting member

48‧‧‧ bolt

49‧‧‧Second connection member

49A‧‧‧ first component

49B‧‧‧Second component

50‧‧‧ bolt

51‧‧‧ bolt

100‧‧‧ Stator

101a‧‧‧ toothed part

101b‧‧‧ lower end

101‧‧‧Silker core

102‧‧‧ coil

110‧‧‧Outer rotor

111‧‧‧ permanent magnet

112‧‧‧Rotor core

112a‧‧‧through hole

200‧‧‧stator

201‧‧‧Silker core

201a‧‧‧stator

202‧‧‧ coil

210‧‧‧Outer rotor

211‧‧‧ permanent magnet

212‧‧‧Rotor core

212a‧‧‧through hole

212b‧‧‧ sloped surface

220‧‧‧2nd cylinder support member

221‧‧‧Flange

222‧‧ ‧ step

230‧‧‧ sleeve

231‧‧ ‧ step

L‧‧‧ axis

P1‧‧‧ first fixed position

P2‧‧‧Second fixed position

‧‧‧‧ angle

Fig. 1 is a perspective view of a shifting device according to a first embodiment of the present invention.

Fig. 2 is a longitudinal sectional view showing a transmission device according to a first embodiment of the present invention.

Fig. 3 is an enlarged view of a main portion including a first crown gear, a second crown gear, and a third crown gear according to the first embodiment of the present invention.

Fig. 4 is a perspective view of the first crown gear of the first embodiment of the present invention.

Fig. 5 is a front elevational view showing the first crown gear, the second crown gear, and the third crown gear of the first embodiment of the present invention.

Fig. 6 is an explanatory view for explaining the coarse motion of the transmission device according to the first embodiment of the present invention.

Fig. 7 is an explanatory view for explaining the fretting of the shifting device according to the first embodiment of the present invention.

Fig. 8 is a longitudinal sectional view showing a transmission device according to a second embodiment of the present invention.

Fig. 9 is an explanatory view for explaining the coarse movement of the transmission device according to the second embodiment of the present invention.

Fig. 10 is an explanatory view for explaining the fine movement of the speed change device according to the second embodiment of the present invention.

Figure 11 is a longitudinal sectional view showing a transmission device according to a third embodiment of the present invention.

Figure 12 is a longitudinal sectional view showing a transmission device according to a fourth embodiment of the present invention.

Claims (8)

A shifting device having: First crown gear; Second crown gear; a third crown gear having opposite teeth facing the first crown gear and opposing teeth facing the second crown gear; and a cam portion that engages the third crown gear with respect to the first crown gear and the second crown in such a manner that the third crown gear meshes with the first crown gear and the third crown gear meshes with the second crown gear The gear is inclined, and the third crown gear is fluctuated in such a manner that the meshing portion moves in the circumferential direction; Any one of the first crown gear and the second crown gear has a plurality of shift gears having different numbers of teeth divided in the radial direction; A switching mechanism having a shifting gear that is fixed from among the plurality of shifting gears. A shifting device as claimed in claim 1, wherein The switching mechanism switches the fixed shift gear in accordance with the rotation direction. The shifting device of claim 2, wherein The plurality of shifting gears have a first shifting gear and a second shifting gear, and The above switching mechanism has: a first one-way clutch that rotates the first shifting gear in only one direction; and a second one-way clutch that rotates the second shift gear only in one direction opposite to the first shift gear. A shifting device as claimed in claim 1 or 2, wherein The plurality of shifting gears have a first shifting gear and a second shifting gear, The above switching mechanism has: a wedge portion that is inserted into a gap between the first shift gear and the second shift gear, and includes an inclined portion that is axially movable to abut against the first shift gear and the second shift gear; and The movable portion moves the wedge portion in the axial direction between a first fixed position at which the first transfer gear is fixed and a second fixed position at which the second transfer gear is fixed. A shifting device according to any one of claims 1 to 4, wherein The plurality of shifting gears include shifting gears having the same number of teeth as the opposing teeth of the third crown gear. A shifting device according to any one of claims 1 to 5, wherein A motor for rotating the cam portion is provided inside the radial direction of the cam portion. The shifting device of claim 6, wherein The motor is further disposed inside the radial direction of at least one of the first crown gear, the second crown gear, and the third crown gear. A shifting device according to any one of claims 1 to 7, which is provided with a motor having a stator and an outer rotor, and The outer rotor is integral with the cam portion.