WO2017126321A1

WO2017126321A1 - Reduction gear and reduction gear-equipped motor

Info

Publication number: WO2017126321A1
Application number: PCT/JP2017/000075
Authority: WO
Inventors: 田中　稔
Original assignee: プラトー株式会社
Priority date: 2016-01-18
Filing date: 2017-01-05
Publication date: 2017-07-27

Abstract

The present invention addresses the problem of providing a reduction gear-equipped motor capable of achieving weight reduction and cost reduction. Provided as a solution to this problem is a reduction gear-equipped motor (1) that is equipped with a reduction gear (3) that reduces the speed of the rotation of a motor (2) and outputs the rotation from an output shaft (16), wherein an output gear (15) comprises: a gear body (50) made from a synthetic resin, such that gear teeth (53) are formed on the outer wall, a recessed part (54) is formed on one side face, and a plurality of projections (55) are formed on the inner wall of the recessed part (54); and a power transmission body (52) that has a ring part (58), into the outer wall of which a plurality of grooves (62) are recessed, a fitting part (59), which is disposed at the center of the ring part (58) and into the inner wall of which an engaging part (64) of the output shaft (16) fits, and a damper part (61), which has a plurality of damper pieces (60) connecting the inner wall of the ring part (58) to the outer wall of the fitting part (59), said power transmission body (52) being entirely formed integrally from a synthetic resin, and being housed in the recessed part (54) of the gear body (50) such that the projections (55) are inserted into the grooves (62).

Description

Reduction gear and motor with reduction gear

The present invention relates to a speed reducer that decelerates rotation of a motor and outputs it from an output shaft, and a motor with a speed reducer equipped with the speed reducer.

Conventionally, electric motors are often used as drive sources for vehicle wiper devices, power window devices, sunroof devices, and the like. In order to adapt the rotation of the electric motor to each device, it is necessary to decelerate the rotation of the electric motor. For this reason, one unit is formed as a motor with a reduction gear in which the reduction gear is attached to the electric motor.

As such a motor with a reduction gear, the one shown in Patent Document 1 is known.
In the motor with a reduction gear shown in Patent Document 1, a gear case is fixed to the motor, and a rotation shaft of the motor projects inside the gear case. A worm is connected to the rotation shaft, and an output gear ( A worm wheel) and a one-stage reduction structure in which an output shaft for external transmission is fitted to the output gear.

FIG. 16 shows a specific configuration of the output gear of the motor with a reduction gear shown in Patent Document 1.
The output gear 7 divides a portion between the insertion hole 7b formed at the center and the outer teeth into three parts at intervals of 120 ° in the circumferential direction, and is a fan-shaped partition space portion opened to the hub 9 side. 7a, 7a, 7a. An external output shaft is rotatably inserted into the insertion hole 7b.
The damper 8 has a fan shape corresponding to the partition space portion 7a, and a cut portion 8a is formed at the center of the outer peripheral arc portion.

The hub 9 is made of a metal plate, and has three projecting pieces 9a cut and raised on the damper 8 side. In addition, a shaft hole 9b is provided in the center of the shaft for connecting to the end of the external output shaft in a non-rotating state, and each projecting piece 9a is engaged with the cut portion 8a of the damper 8. The cover 10 is formed of a circular thin plate member made of metal or resin. Moreover, the cover 10 has the groove part 10a for each protrusion piece 9a of the hub 9 to each fit. At the center of the cover 10, there is an insertion hole 10b through which the external output shaft is rotatably inserted. In the assembled state, the cover 10 closes the opening 9c formed in the hub 9 by cutting and raising the protruding piece 9a.

In the motor with a speed reducer having such a configuration, the output gear 7 is rotated through the worm by driving the motor, and the cover 10 and the hub 9 are rotated through the damper 8 by the rotation of the output gear 7. The external output shaft connected to is decelerated and driven.
Further, when the external output shaft is restrained due to some obstacle from the driven body connected to the external output shaft, the hub 9 connected to the external output shaft stops simultaneously, while the output gear 7 continues to rotate. Thus, the impact force generated therewith is absorbed by compressing the damper 8 provided between the cover 10 engaged with the hub 9 and the output gear 7 in the rotation direction of the output gear 7. I have to. The output gear 7 stops after rotating to some extent with respect to the hub 9 and the cover 10.

Japanese Patent Laid-Open No. 9-140091

In the conventional motor with a reduction gear, the driving force is transmitted from the output gear 7 to the external output shaft through the damper 8 and the hub 9. A driving force is directly transmitted to the external output shaft from a hub 9 made of a metal plate. Therefore, a large torque is applied between the hub 9 and the external output shaft. In particular, since the hub 9 is a thin metal plate and a large torque is applied thereto, there is a limit to reducing the thickness, and it is necessary to use a thick metal plate as it is. It is an obstacle. When processing the hub 9, it may be possible to reduce the thickness of the other parts by drawing the metal plate and thickening only the fitting part with the external output shaft to increase the strength, but the processing cost increases. There is a problem of doing.

Also, since the three dampers 8 are made of rubber, there is a problem that it is difficult to reduce the weight. When an impact force is applied, the rubber damper 8 absorbs the impact force. However, since the amount of deflection of the rubber is small, only a short-time impact force can be absorbed. Further, the output gear 7 rotates to some extent with respect to the hub 9 and the cover 10, but the rotation angle is small, and there is a problem that the output gear 7 does not function effectively against a large impact and a complicated impact. Furthermore, there are problems that the parts such as the output gear 7, the three dampers 8, the cover 10, and the hub 9 are necessary, and that the number of parts is large and the cost is high.

Therefore, the present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide a reduction gear and a motor with a reduction gear that can be reduced in weight and cost.

A speed reducer according to the present invention is a speed reducer that decelerates the rotation of a motor and outputs the reduced speed from an output shaft. The speed reducer is disposed in a gear case and rotatably in the gear case, and is connected to the worm shaft of the motor. And an output gear that is rotatably disposed in the gear case and meshes with the worm directly or via an intermediate gear, and the output shaft is fitted to the fitting portion provided at the center at the engaging portion. The output gear has a gear tooth formed on the outer wall, a recess is formed on one side surface, and a plurality of protrusions are formed on the inner wall of the recess at predetermined intervals in the circumferential direction. A resin gear body, a ring portion having a plurality of grooves recessed in the outer wall at a required interval in the circumferential direction, and provided at the center of the ring portion, and the engagement portion of the output shaft on the inner wall Cylinder with spline groove to fit It has a damper part provided with the above-mentioned fitting part and a bent part, and has a plurality of damper pieces which connect between the inner wall of the ring part and the outer wall of the fitting part, and the whole is integrally formed of synthetic resin. And a power transmission member housed in the recess of the gear body so that the protrusion of the gear body fits into the groove.

A motor with a speed reducer according to the present invention is a motor with a speed reducer comprising a motor and a speed reducer that decelerates the rotation of the motor and outputs it from an output shaft, the speed reducer comprising: a gear case; The worm is rotatably disposed in the gear case, and is rotatably disposed in the gear case, and meshes with the worm directly or through an intermediate gear, and is provided at the center. An output gear in which the output shaft is fitted in the engaging portion in the engaging portion, the output gear is formed with gear teeth on the outer wall, a concave portion is formed on one side surface, and the inner wall of the concave portion is A synthetic resin gear main body having a plurality of protrusions formed at a predetermined interval in the circumferential direction, a ring portion having a plurality of grooves recessed in the outer wall at a predetermined interval in the circumferential direction, Located in the center The cylindrical fitting portion formed with a spline groove into which the engaging portion of the output shaft is fitted, and a bent portion are provided to connect the inner wall of the ring portion and the outer wall of the fitting portion. It has a damper portion having a plurality of damper pieces, and is formed integrally with synthetic resin, and is accommodated in the recess of the gear body so that the protrusion of the gear body fits into the groove. And a power transmission body.

The cylindrical fitting portion can be formed as a fitting portion that is long in the axial direction and has one end projecting laterally from the ring portion and the damper portion.
The engaging portion of the output shaft that fits into the fitting portion of the power transmission body may be a synthetic resin engaging portion formed around a core metal body.
It is preferable to mix carbon fiber into the engaging portion made of synthetic resin.

The output shaft has a metal external transmission gear on one end side, and the external transmission gear can be fixed to the core metal via a resin injected around the core metal. .
In order to form the groove of the ring part, the damper piece extends laterally from both outer walls of the inward projecting part projecting inward of the ring part, and is bent in the opposite direction in the middle. Thereafter, the first damper pieces formed symmetrically to reach the outer wall of the fitting portion and the inner wall of the ring portion between the adjacent grooves extend halfway through the first The second damper piece is formed in two symmetrical shapes that are bent in opposite directions at positions different from the curved part of the damper piece and then reach the outer wall of the fitting portion. it can.

According to the present invention, the damper part in the power transmission body is composed of a plurality of damper pieces made of synthetic resin that connect the ring part and the fitting part. Therefore, when an impact force or a large load is applied, the damper piece bends greatly, Therefore, the rotation angle of the external output gear can be increased with respect to torque fluctuation and impact force of the output gear and the external output gear, and the rotation of the external output gear can be made smooth and quiet. In addition, since the output gear is composed of a synthetic resin gear body and a synthetic resin power transmission body, the weight can be greatly reduced. Furthermore, conventionally, as the output gear structure, three rubber dampers, metal hubs, and the like have been required. However, in the present invention, the damper and hub are integrated as a synthetic resin power transmission body. As a result, it is possible to reduce the number of parts and reduce the cost.

It is a front view which shows the state which removed the cover of the reduction gear part of the motor with a reduction gear. It is explanatory sectional drawing which shows the gear structure of a reduction gear. It is an assembly drawing of an output gear and an output shaft. It is a front view of a power transmission body. It is explanatory drawing sectional drawing of a power transmission body. It is sectional drawing of an output shaft. It is a right view of an output shaft. It is a left view of an output shaft. It is sectional drawing which shows the assembly | attachment structure of an output gear and an output shaft. It is a top view of a rotation control mechanism. It is the elements on larger scale of FIG. It is a perspective view of a rotation control mechanism. It is a perspective view which shows the relationship between a 1st lever and a 2nd lever. It is a top view of the state where the hook removed from the latching part. It is a top view in the state where a lock claw removed from a lock gear. It is an assembly drawing which shows the structure of the conventional output gear.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.
FIG. 1 is a front view showing a state where a cover of a reduction gear portion of a motor 1 with a reduction gear is removed, and FIG.
Reference numeral 2 denotes a motor, which is fixed to the gear case 11 of the speed reducer 3 by screws (not shown). The motor 2 is composed of a brush motor that can rotate forward and backward.
The gear structure of the speed reducer 3 is housed in the gear case 11. The gear case 11 includes a case main body 11A and a lid body 11B (FIG. 2). The lid 11B is fixed to the case main body 11A by fixing means such as screws (not shown).

A rotating shaft 21 of the motor 2 protrudes into the gear case 11, and a worm 12 is fixed coaxially with the rotating shaft 21 at a tip portion thereof. The other end of the worm 12 is rotatably supported by a bearing (not shown). The worm 12 is preferably made of resin. The rotating shaft 21 and the worm 12 may be provided integrally.
Reference numeral 14 denotes an intermediate gear. As shown in FIG. 2, a worm wheel 14A, a pinion gear 14B fixed on one surface of the worm wheel 14A coaxially with the worm wheel 14A, and coaxial with the worm wheel 14A. The worm wheel 14A includes a locking gear 14C fixed to the other surface of the worm wheel 14A.
The intermediate gear 14 is preferably formed integrally with resin.

The worm wheel 14A meshes with the worm 12. Thereby, the first-stage deceleration is performed.
The pinion gear 14B is set to have fewer teeth than the worm wheel 14A. The number of teeth of the pinion gear 14B is preferably as few as possible to increase the reduction ratio, and is preferably 5-7. The pinion gear 14 </ b> B meshes with an output gear 15 that is rotatably disposed in the gear case 11. As a result, the second-stage deceleration is performed. The output of the output gear 15 is performed through the output shaft 16.
The output gear 15 is made of resin.
Thus, by making the worm 12, the intermediate gear 14 and the output gear 15 from resin, the generation of noise can be reduced as much as possible, and it can be manufactured at low cost.

Next, the output gear 15 will be described with reference to FIGS.
FIG. 3 is an assembly diagram of the output gear 15 and the output shaft 16.
As shown in FIG. 3, the output gear 15 includes a synthetic resin gear body 50 and a synthetic resin power transmission body 52.
The gear body 50 has a gear tooth 53 formed on the outer wall thereof, and a circular recess 54 formed on one side of the gear body 50. A plurality (six in FIG. 3) of protrusions 55 are formed on the inner peripheral wall of the recess 54 at a required interval in the circumferential direction.
In the center of the gear body 50, a cylindrical body 56a having a shaft hole 56 through which the output shaft 16 is rotatably inserted is provided.
The gear body 50 is formed of a hard synthetic resin.

4 is a front view of the power transmission body 52, and FIG. 5 is an explanatory sectional view thereof.
The power transmission body 52 is integrally formed of a relatively soft synthetic resin such as polyacetal or elastomer.
The power transmission body 52 includes a ring portion 58, a fitting portion 59 located at the center of the ring portion 58, and a damper portion 61 having a large number of damper pieces 60 that connect the ring portion 58 and the fitting portion 59. ing.
A plurality (six in FIG. 4) of grooves 62 are provided on the outer wall of the ring portion 58 at a required interval in the circumferential direction. The groove 60 is formed in a size that allows the projection 55 of the gear body 50 to be fitted.

The fitting portion 59 has a cylindrical shape, and a spline groove 65 into which the engaging portion 64 (FIG. 6) of the output shaft 16 is fitted is formed on the inner wall. In the present embodiment, the fitting portion 59 has a cylindrical shape with a large diameter as much as possible, and a large number of spline grooves 65 are formed on the large-diameter inner wall. In the example of FIG. 4, there are 12 spline grooves 65.
Further, as clearly shown in FIG. 5, it is preferable that the fitting portion 59 is formed in a cylindrical shape having a relatively long length, with one end projecting laterally from the ring portion 58 and the damper piece 60. In this way, the fitting portion 59 is formed in a cylindrical shape that is long in the axial direction, and by providing a large number of spline grooves 65 on the inner wall, the fitting area with the output shaft 16 becomes large, and a resin fitting is made. Even in the joint portion 59, force can be transmitted to the output shaft 16 without difficulty.

The damper piece 60 in the damper portion 61 can transmit power from the gear body 50 to the output shaft 16 through the protrusion 55, the damper portion 61, and the fitting portion 59, and between the gear body 50 and the output shaft 16. The shape and structure are not particularly limited as long as they can absorb the impact force generated in the case.
The damper piece 60 in the present embodiment includes two first damper pieces 60a and two second damper pieces 60b.

The first damper pieces 60a extend laterally from both outer walls of the inward projecting portions 66 projecting inwardly of the ring portion 58 to form the grooves 62 of the ring portion 58, and are opposed to each other in the middle. After being bent in the direction, it is composed of two

damper pieces

60a and 60a that are formed symmetrically and reach the outer wall of the fitting portion 59.
The second damper piece 60b extends from the inner wall of the ring portion 58 between the adjacent grooves 62, and is different from the curved portion of the first damper piece 60a in the middle (a position that does not overlap spatially). The

second damper pieces

60b and 60b are formed in two symmetrical shapes that are bent in opposite directions to each other and reach the outer wall of the fitting portion 59. As described above, the first damper piece 60a and the second damper piece 60b are curved and provided in a range that does not overlap with each other in the ring portion 58, so that they can be efficiently arranged in the space of the ring portion 58. ing.

6 is a cross-sectional view of the output shaft 16, FIG. 7 is a right side view thereof, and FIG. 8 is a left side view thereof.
A core metal body 68 has a large diameter portion 68a, a first small diameter portion 68b, a second small diameter portion 68c, and a third small diameter portion 68d formed in this order. In the small diameter portion, the first small diameter portion 68b has the smallest diameter, and the diameter increases in the order of the second small diameter portion 68c and the third small diameter portion 68d.

Reference numeral 70 denotes a metal external output gear, which is formed in a hollow shape, and is injected around the first small diameter portion 68b of the core metal body 68 by injecting resin together with the plain washer 71 by insert molding. 72 is fixed. The injection resin 72 is formed in a large diameter cylindrical shape over the second small diameter portion 68c and a part of the third small diameter portion 68d. An end portion of the large-diameter injection resin 72 is formed in the engaging portion 64, and the engaging portion 64 has a protrusion 73 that fits into the spline groove 65 of the fitting portion 59 of the power transmission body 52. Is formed.

A cylindrical body 56a having a shaft hole 56 of the gear main body 50 is fitted into the portion of the large-diameter cylindrical injection resin 72 during assembly.
An e-ring circumferential groove 75 is formed in the middle of the third small diameter portion 68 d of the core metal body 68.
The first small-diameter portion 68b and the injection resin 72, and the injection resin 72 and the output gear 70 are engaged with each other to prevent the rotation.
As the injection resin 72, a nylon resin having a high strength can be suitably used. In addition, it is preferable to add strength fibers such as carbon fibers to the injected resin 72 to further increase the strength.

FIG. 9 is a cross-sectional view showing an assembly structure of the output gear 15 and the output shaft 16.
The output gear 15 is assembled by housing the power transmission body 52 in the recess 54 of the gear body 50 so that the protrusion 55 fits into the groove 62 of the ring portion 58.
The output gear 15 is disposed in the case main body 11A so as to mesh with the pinion gear 14B of the worm wheel 14A. Next, the lid 11B is assembled.

Next, the output shaft 16 has its third small diameter portion 68d inserted into the bearing portion 76 (FIG. 9) of the case main body 11A, and the protrusion 73 of the engaging portion 64 is fitted into the spline groove 65. In this manner, the output gear 15 is fitted. In this state, the output shaft 16 is assembled such that the third small diameter portion 68d is supported by the bearing portion 76 and the large diameter portion of the injection resin 72 is supported by the bearing portion 77 (FIG. 9) of the lid 11B. It is done. Then, the lid body 14B is fixed to the case main body 11A with a screw or the like (not shown) to be assembled as a motor with a speed reducer.
The bearings 76 and 77 may be made of sintered metal impregnated with oil.
Reference numeral 78 denotes an e-ring.

As described above, in the motor with a speed reducer 1 according to the present embodiment, the damper portion 61 in the power transmission body 52 is composed of a plurality of damper pieces 60 made of synthetic resin that connect the ring portion 58 and the fitting portion 59. Therefore, when an impact force or a large load is applied, the damper piece 60 bends greatly. Therefore, the rotation angle of the external output gear 70 can be increased with respect to the torque fluctuation and impact force of the output gear 15 and the external output gear 70, The rotation of the output gear 70 can be made smooth and quiet. In particular, by making the damper portion 61 made of a soft synthetic resin such as polyacetal or elastomer, the amount of deflection can be increased and the impact force can be effectively absorbed.
Further, since the output gear 15 is composed of the synthetic resin gear body 50 and the synthetic resin power transmission body 52, the weight can be greatly reduced. For example, in the motor 1 with a speed reducer having an overall weight of about 370 to 380 g, the overall weight can be reduced by about 20 g compared to the conventional one. Weight reduction is an extremely important matter for vehicle parts.

Conventionally, as the output gear structure, as shown in FIG. 16, three rubber dampers 8 and a metal hub 9 were required, but in this embodiment, the functions of the damper and the hub are combined. Since the power transmission body 52 having an integral structure made of resin is provided, the number of parts can be reduced and the cost can be reduced. Further, even when the power transmission body 52 is made of resin, the fitting portion 59 with the output shaft 16 has a large diameter and a long cylindrical shape in the axial direction, and the output shaft 16 The engagement portion 64 is made of resin, so that the fitting area between the two can be increased, it is possible to sufficiently withstand the large torque applied, and force can be transmitted to the output shaft 16 without difficulty. it can.

In the above embodiment, the metal external output gear 70 is fixed to the core metal body 68 by insert molding using the injection resin 72, but the entire output shaft 16 (external output gear 70 and core metal). The body 68) may be made of synthetic resin.
That is, conventionally, since the impact force applied to the output shaft 16 may momentarily reach several times the maximum torque of the motor 2, the entire output shaft is made of metal.
However, in the present embodiment, as described above, since the impact force can be absorbed almost completely by the synthetic resin damper piece 60 of the damper portion 61, the torque of the output gear 16 and the external output gear 70 is the same as that of the motor 2. The maximum torque value can be set. Therefore, for the strength calculation, the entire output shaft 16 can be made of an integral structure with a nylon-based resin mixed with reinforcing fibers such as carbon fibers.

Next, the rotation restriction mechanism 17 of the output gear 15 will be described as an optional structure.
In the present embodiment, the advance angles of the worm 12 and the worm wheel 14A are set to be large, for example, 15 ° or more.
As described above, by setting the advance angle of the worm 12 and the worm wheel 14A to be large, the overall transmission efficiency can be increased, for example, 60% or more, whereby the output torque can be increased. Therefore, when the same output torque is obtained, the motor can be made smaller than the conventional motor, the entire apparatus can be reduced in size, and the cost can be reduced.

In a conventional motor with a reduction gear, the transmission efficiency is designed to be 40%. In this case, 100/40 = 2.5. That is, the motor 2 requires a motor having a torque 2.5 times the required output torque.
When the transmission efficiency is 60%, 100/60 = 1.67. The motor 2 may have a torque of 1.67 times the required output torque, and may be a conventional motor having a torque of about 70%. 100/75 = 1.33 when the transmission efficiency is 75%. The motor 2 may have a torque 1.33 times the required output torque, and may be a conventional small motor having a torque of about 50%.

However, if the advance angle of the worm 12 and the worm wheel 14A is increased to increase the transmission efficiency, the self-locking function is lowered.
Therefore, in the present embodiment, the mechanical rotation restricting mechanism 17 is provided to lock the locking gear 14C so that the entire apparatus can be reliably locked.
Hereinafter, the rotation restricting mechanism 17 will be described with reference to FIGS.
10 is a plan view of the rotation restricting mechanism 17, FIG. 11 is a partially enlarged view thereof, FIG. 12 is a perspective view of the rotation restricting mechanism 17 (however, it is depicted upside down from that of FIG. 10), and FIG. It is a perspective view which shows the relationship between a 1st lever and a 2nd lever.

These rotation restricting mechanisms 17 are all disposed in the gear case 11.
Reference numeral 24 denotes a first lever, which is provided at one end so as to be rotatable around a shaft 25. The other end of the first lever 24 is provided with a lock claw 26 that is detachably engaged with the locking gear 14 </ b> C in the intermediate gear 14. A first urging member (coil spring) 27 is linked to the first lever 24, and the first urging member 27 engages the first lever 24 and the locking claw 26 engages with the locking gear 14C. Energize in the direction to do. On the lower surface side of the first lever 24, a locking portion 28 having an approximately L shape is provided.

30 is an electromagnetic solenoid having a plunger 31 that is attracted and retracted when energized. A pin 32 is provided on the distal end side of the plunger 31. The pin 32 passes through a long hole 33 provided in the first lever 24. The long hole 33 is provided so as to be long in the rotation direction of the first lever 24. The pin 32 is positioned on one edge side of the long hole 33 when the first lever 24 is biased by the biasing member 27 and the lock claw 26 is in a position engaged with the locking gear 14C. is doing. The first lever 24 is not rotated until the pin 32 contacts the edge of the other side of the long hole 33 when the electromagnetic solenoid 30 is driven and the plunger 31 is pulled. When the pin 32 comes into contact with the other side edge of the long hole 33 and the plunger 31 is still pulled, the first lever 24 is rotated, whereby the lock gear 14C of the lock claw 26 is rotated. Is disengaged.

36 is a second lever having an almost L shape. The second lever 36 is provided so as to be rotatable about a shaft 37. A hook 38 that can be locked to the locking portion 28 of the first lever 24 to prevent the rotation of the first lever 24 is provided at one end of the second lever 36. A second urging member (coil spring) 39 is linked to the other end side of the second lever 36. The second urging member 39 urges the second lever 36 in the direction in which the hook 38 is engaged (contacted) with the engaging portion 28 (the counterclockwise rotation direction in FIGS. 10 and 11). On the second lever 36, a pin 40 serving as a pressed portion is provided.

42 is a third lever, which is provided so as to be rotatable about a shaft 25 common to the first lever 24. The pin 32 provided in the plunger 31 passes through the hole 43 provided in the third lever 42. As a result, when the electromagnetic solenoid 30 is driven and the plunger 31 is pulled, the third lever 36 is immediately rotated. Therefore, the first lever 24 and the third lever 42 are rotated with a time difference while the pin 32 moves in the long hole 33. The hole 43 is formed in a slightly oval shape so that the third lever 42 can turn in an arc shape around the shaft 25. The third lever 42 is provided with a pressing portion 44 that comes into contact with a pin 40 that is a pressed portion provided on the second lever 36.

When the third lever 42 is rotated, the pressing portion 44 presses the pressed portion 40, and the second lever 36 is rotated in a direction in which the hook 38 is disengaged from the locking portion 28 of the first lever 24. Let That is, the surface of the pressing portion 44 that contacts the pressed portion 40 is formed as a cam surface 44 a that forms a required angle with respect to the pressed portion 40. When the plunger 31 is pulled and the third lever 42 is rotated in the counterclockwise direction in FIG. 11, the cam surface 44a moves the pin (pressed portion) 40 to the left in FIG. And the second lever 36 is rotated in the clockwise direction against the urging force of the second urging member 39 to disengage the hook 38 from the locking portion 28. . In addition, in order to reduce the friction between the pin 40 which is a to-be-pressed part and the cam surface 44a, it is good to set it as a roller structure.
As shown in FIG. 12, the rotation restricting mechanism 17 is preferably assembled on the base 46 and unitized.

The motor 1 with a speed reducer and the speed reducer 3 according to the present embodiment are configured as described above.
The operations of the motor 1 with the speed reducer and the speed reducer 3 itself are as described above.
Hereinafter, the operation of the rotation restricting mechanism 17 will be described.
1 and 10 in which the motor 2 is stopped, the lock claw 26 is engaged with the locking gear 14C, and the hook 38 is engaged with the engaging portion 28, so that the first lever 24 is engaged. Is completely prevented from rotating. Therefore, for example, when the motor 1 with a speed reducer is used as a drive source for a power window of an automobile, the window can be completely locked even when an external force such as opening the window is applied at the time of stoppage. Can be reliably prevented. Moreover, even when the motor 1 with a speed reducer is used for a power seat of an automobile, even if an external force is applied to the seat due to a vehicle accident such as a collision, the seat can be prevented from moving and the driver's safety can be ensured. That is, in the motor 1 with a speed reducer according to the present embodiment, the rotation restricting mechanism 17 is provided, so that when the output of the motor is stopped, an operation that the applied devices cannot expect due to malfunction, malicious operation, etc. It is possible to reliably prevent this.

Next, the case where the motor 2 is driven will be described.
When the corresponding device such as a power window is operated, when the switch is turned on and the motor 2 is driven, the electromagnetic solenoid 30 is also driven almost simultaneously.
When the electromagnetic solenoid 30 is driven, when the plunger 31 is pulled, the third lever 42 is first rotated, and the pressing portion 44 presses the pin 40 that is the pressed portion, and the second lever 36 is moved. In FIG. 10, it is rotated in the clockwise direction, whereby the hook 38 is disengaged from the locking portion 28 (FIG. 14). Next, the first lever 24 is rotated with a time difference sufficient for the pin 32 to move in the long hole 33, the lock claw 26 is disengaged from the lock gear 14C (FIG. 15), and the corresponding device is driven. Will be.
When the motor 2 is stopped, the first lever 24, the second lever 36, and the third lever 42 are shown in FIG. 10 by the urging force of the first urging member 27 and the second urging member 39. It will be understood that the state is restored and the locking gear 14C is locked.

In the present embodiment, torque from the locking gear 14C is received by being distributed (distributed) between the locking gear 14C and the locking claw 26 and between the locking portion 28 and the hook 38. . Further, the static frictional force is also shared between the locking gear 14C and the locking claw 26, between the locking portion 28 and the hook 38, and the like.

And, at the time of driving, the second lever 36 is rotated in advance of the first lever 24 as described above. Thus, when the electromagnetic solenoid 30 is energized, the hook 38 and the locking portion 28 are first disengaged. In this case, the torque and static friction force acting between the two are shared and relatively small. Therefore, the engagement between the two is easily released. Next, the first lever 24 is rotated with a time difference, and the locking between the locking gear 14C and the locking claw 26 is released, but the torque and static friction force acting between the two are also shared and compared. Therefore, the engagement between the two is easily disengaged.

In the above embodiment, the description has been given on the case where the advance angle of the worm is set to 15 ° or more, the transmission efficiency is set to 60% or more and the rotation restricting mechanism is provided. Of course, the output gear structure according to the present invention can be adopted for a reduction gear structure having a function without the rotation restricting mechanism.
In the above embodiment, the two-stage reduction gear structure has been described. However, the output gear structure according to the present invention can also be adopted for the output gear (worm wheel) in the one-stage reduction gear structure.

Claims

A speed reducer that decelerates the rotation of the motor and outputs it from the output shaft,
A gear case,
A worm rotatably disposed in the gear case and connected to the rotation shaft of the motor;
An output gear which is rotatably disposed in the gear case and meshes with the worm directly or via an intermediate gear, and the output shaft is fitted in the engaging portion to a fitting portion provided in the center. And
The output gear is
A gear body made of synthetic resin, in which gear teeth are formed on the outer wall, a recess is formed on one side surface, and a plurality of protrusions are formed on the inner wall of the recess with a predetermined interval in the circumferential direction;
A ring part in which a plurality of grooves are recessed in the outer wall at a required interval in the circumferential direction;
The tubular fitting portion provided at the center of the ring portion and having a spline groove formed on the inner wall for fitting the engaging portion of the output shaft.
And a damper part provided with a plurality of damper pieces provided to be bent and connecting between the inner wall of the ring part and the outer wall of the fitting part,
A power transmission body housed in the recess of the gear body so that the whole is integrally formed of synthetic resin, and the protrusion of the gear body is fitted into the groove,
A speed reducer comprising:
The reduction gear according to claim 1, wherein the cylindrical fitting portion is formed as a fitting portion that is long in the axial direction and has one end projecting laterally from the ring portion and the damper portion. .
The engagement portion of the output shaft that fits into the fitting portion of the power transmission body is an engagement portion made of a synthetic resin formed around a core metal body. 2. The reducer according to 2.
The speed reducer according to claim 3, wherein carbon fiber is mixed in the engaging portion made of synthetic resin.
The output shaft has a metal external transmission gear on one end side, and the external transmission gear is fixed to the core metal via a resin injected around the core metal. The speed reducer according to claim 3 or 4.
The damper piece is
Extending laterally from both outer walls of the inward projecting portion projecting inwardly of the ring portion to form the groove of the ring portion, and in the middle, curved in opposite directions to each other, then the fitting Two first damper pieces formed symmetrically to the outer wall of the part,
It extends from the inner wall of the ring part between the adjacent grooves, and is bent in the opposite direction at a position different from the curved part of the first damper piece, and then reaches the outer wall of the fitting part. Two second damper pieces formed symmetrically, and
The speed reducer according to any one of claims 1 to 5, further comprising:
A motor,
A motor with a speed reducer comprising a speed reducer that decelerates rotation of the motor and outputs it from an output shaft,
The speed reducer is
A gear case,
A worm rotatably disposed in the gear case and connected to the rotation shaft of the motor;
An output gear which is rotatably disposed in the gear case and meshes with the worm directly or via an intermediate gear, and the output shaft is fitted in the engaging portion to a fitting portion provided in the center. And
The output gear is
A gear body made of synthetic resin, in which gear teeth are formed on the outer wall, a recess is formed on one side surface, and a plurality of protrusions are formed on the inner wall of the recess with a predetermined interval in the circumferential direction;
A ring part in which a plurality of grooves are recessed in the outer wall at a required interval in the circumferential direction;
The tubular fitting portion provided at the center of the ring portion and having a spline groove formed on the inner wall for fitting the engaging portion of the output shaft.
And a damper part provided with a plurality of damper pieces provided to be bent and connecting between the inner wall of the ring part and the outer wall of the fitting part,
A power transmission body housed in the recess of the gear body so that the whole is integrally formed of synthetic resin, and the protrusion of the gear body is fitted into the groove,
A motor with a speed reducer, comprising:
8. The reduction gear according to claim 7, wherein the cylindrical fitting portion is formed in a fitting portion that is long in an axial direction so that one end side protrudes laterally from the ring portion and the damper portion. motor.
8. The synthetic resin engaging portion formed around a core metal body, wherein the engaging portion of the output shaft that fits into the fitting portion of the power transmission body is formed. 8. A motor with a reduction gear according to 8.
The motor with a speed reducer according to claim 9, wherein carbon fiber is mixed in the engaging portion made of synthetic resin.
The output shaft has a metal external transmission gear on one end side, and the external transmission gear is fixed to the core metal via a resin injected around the core metal. The motor with a reduction gear according to claim 9 or 10.
The damper piece is
Extending laterally from both outer walls of the inward projecting portion projecting inwardly of the ring portion to form the groove of the ring portion, and in the middle, curved in opposite directions to each other, then the fitting Two first damper pieces formed symmetrically to the outer wall of the part,
It extends from the inner wall of the ring part between the adjacent grooves, and is bent in the opposite direction at a position different from the curved part of the first damper piece, and then reaches the outer wall of the fitting part. Two second damper pieces formed symmetrically, and
The motor with a reduction gear according to any one of claims 7 to 11, characterized by comprising: