JP7091207B2 - Motor with reducer - Google Patents

Description

The present invention relates to a motor with a speed reducer.

Conventionally, a motor with a speed reducer in which a motor is joined to a gear casing is known.
For example, in the motor with a speed reducer disclosed in Patent Document 1, a female screw groove is formed in the motor mounting portion of the gear casing (case). On the other hand, a male screw groove is formed on the outer peripheral surface of the motor casing of the motor. The gear casing and the motor are connected by fitting the female thread groove of the gear casing and the male thread groove of the motor casing.

On the other hand, the motor with a speed reducer disclosed in Patent Document 2 includes a gear casing having a circular opening for accommodating the helical gear, and a lid for closing the opening of the gear casing. The motor is provided with a fitting portion, and the gear casing is provided with a fitted portion. When the fitting portion of the motor is fitted into the fitted portion of the gear casing, the motor is incorporated into the gear casing. Then, when the motor is incorporated into the gear casing, the engagement provided on the lid is provided in the space formed by the gear casing-side non-engagement portion of the fitted portion and the motor-side fitted portion of the fitting portion. Insert the protrusion. As a result, the fitted portion on the motor side and the non-engaged portion on the gear casing side are fixed, and the motor is fixed to the gear casing.

Japanese Unexamined Patent Publication No. 2006-218922 Japanese Patent No. 5267372

When driving a motor or the like, loads on both sides in the direction along the shaft (thrust direction) act on the shaft provided in the motor. Of the load in the thrust direction, the load on the tip end side of the shaft is supported by a case or the like, but the load on the base end side of the shaft is supported by the motor casing provided in the motor. Therefore, it is necessary to firmly connect the gear casing and the motor casing of the motor.
In this case, the connection structure between the gear casing and the motor becomes complicated, and the cost required for manufacturing the motor with a speed reducer increases.

The present invention has been made in view of such problems, and the load acting on the shaft on both sides in the thrust direction is supported by the case in a simple configuration to simplify the connection between the case and the motor. It is an object of the present invention to provide a motor with a speed reducer capable.

In order to solve the above problems, the present invention proposes the following means.
The motor with a speed reducer of the present invention accommodates a motor having a shaft, a first gear fixed to the outer peripheral surface of the shaft, at least a part of the motor, and the first gear, and holds the tip of the shaft. A case having a support surface to support, a support member arranged in the case and supporting the first gear from the base end side of the shaft, and a shaft member arranged in the case and the support member, respectively. It is characterized by having.

According to the present invention, the support member is fixed to the case by the shaft member. Therefore, the support member can be reliably fixed to the case. The support member regulates the movement of the first gear and the shaft to the base end side of the shaft with respect to the case, and the support surface of the case causes the shaft to move to the tip end side of the shaft with respect to the case. It is regulated. As described above, the load acting on both sides in the thrust direction can be supported by the case with a simple configuration of the support member, the shaft member, and the support surface of the case.
Further, since the motor does not need to support the load acting toward the base end side of the shaft, the connection between the case and the motor can be simplified.

Further, in the motor with a speed reducer, the case may be formed with a hole that communicates with the inside of the case and in which the shaft member is arranged.
According to the present invention, the case can be supported by the support member via the shaft member by using the hole portion for adjusting the pressure inside the case.

Further, in the motor with a speed reducer, a holding portion for holding the lubricating material may be formed on the outer surface of the support member that supports the first gear.
According to the present invention, a lubricant that makes the first gear slippery with respect to the support member can be held by the holding portion.

Further, in the motor with a speed reducer, the support member is formed with a through hole in which the shaft member is arranged, and the end of the through hole in the support member is at the end of the through hole. A guide portion may be formed in which the inner diameter gradually increases toward the direction.
According to the present invention, at the time of manufacturing a motor with a speed reducer, the shaft member can be guided into the through hole by a guide portion, and the shaft member can be easily inserted into the through hole.

Further, in the motor with a speed reducer, the support member may be provided with an urging portion for urging the shaft in a direction intersecting the axis of the shaft.
According to the present invention, since the shaft rotates in a state of being urged in the intersecting direction, it is possible to suppress vibration of the shaft and generation of abnormal noise from the shaft when the shaft rotates.

Further, the motor with a speed reducer may be provided with a protruding portion that protrudes from the outer surface of the support member and contacts the inner surface of the case.
According to the present invention, it is possible to prevent the support member loaded by the first gear from rotating around the shaft member.

Further, in the motor with a speed reducer, the first gear is a worm, which is rotatably supported around the support shaft along the direction intersecting the axis of the shaft with respect to the case and meshes with the worm. The worm wheel is provided, and the position where the worm and the worm wheel mesh with each other may be on the side opposite to the shaft member with the shaft interposed therebetween, and may be located on the tip end side of the shaft member with respect to the shaft member. ..
According to the present invention, since the direction of the load input from the worm wheel is substantially equal to the direction from the position toward the shaft member, the load input from the worm wheel can be effectively supported by the shaft member.

According to the motor with a speed reducer of the present invention, the load acting on the shaft on both sides in the thrust direction can be supported by the case with a simple configuration, and the connection between the case and the motor can be simplified.

It is a front view of the motor with a reducer of one Embodiment of this invention. It is a top view of the motor with the speed reducer. It is a vertical sectional view of the motor with the speed reducer. It is a perspective view around the shaft hole of the motor with a speed reducer. It is a perspective view of the thrust receiver and the fixed shaft of the motor with a speed reducer. It is a side view of the same thrust receiver.

Hereinafter, an embodiment of the motor with a speed reducer according to the present invention will be described with reference to FIGS. 1 to 6.
As shown in FIGS. 1 and 2, the motor 1 with a speed reducer of the present embodiment includes a motor 11 and a speed reducer 21.

As shown in FIG. 3, the motor 11 includes a shaft 12, a motor case 13, a magnet (not shown), and a rotor.
The shaft 12 is formed in a rod shape whose axis extends in the first direction X (thrust direction). A worm (first gear) 15 is fixed to the outer peripheral surface of the end portion of the shaft 12 on the first side (one side) X1 (tip side) of the first direction X. The tooth portion of the worm 15 is formed in a spiral shape centered on an axis parallel to the first direction X.
The motor case 13 is formed in a bottomed cylindrical shape. An engaging portion 13a having a larger outer diameter than other portions of the outer peripheral surface is formed on the outer peripheral surface of the motor case 13. The end of the second side (the other side) X2 (base end side) opposite to the first side in the first direction X of the shaft 12 is housed in the motor case 13.
The magnet is fixed to the inner peripheral surface of the motor case 13. The rotor is fixed to the end of the second side X2 of the shaft 12 and faces the magnet.
In the motor 11, when a current is passed through the rotor, the rotor rotates with respect to the magnet, so that the shaft 12 rotates about the axis with respect to the motor case 13.

As shown in FIG. 3, the speed reducer 21 includes a gear casing (case) 22, a thrust receiver 23, a fixed shaft (shaft member) 24, a worm wheel unit 25, and a cover 26 (see FIG. 1). I have.
The gear casing 22 is formed with a shaft hole 29, a shaft hole (hole portion) 30, and a gear hole 31, respectively.
The shaft hole 29 is formed on the outer surface of the second side X2 of the gear casing 22. The shaft hole 29 extends from this outer surface to the first side X1 in the first direction X. The shaft hole 29 does not penetrate the gear casing 22 in the first direction X. A bearing 33 made of a resin having elasticity, wear resistance, and self-lubricating property is arranged on the bottom surface (support surface) 29a of the shaft hole 29.

A pair of engaged portions 34 that engage with the engaging portion 13a of the motor 11 in the first direction X are formed on the opening peripheral edge portion of the shaft hole 29 in the gear casing 22. The engaged portion 34 is a claw formed on the gear casing 22. In addition, three or more engaged portions 34 may be formed in the opening peripheral edge portion of the shaft hole 29 in the gear casing 22.
The pair of engaged portions 34 are arranged so as to face each other with the shaft hole 29 interposed therebetween in the third direction Z orthogonal to the first direction X. The motor 11 is attached to the gear casing 22 by engaging the pair of engaged portions 34 with the engaging portions 13a in a state where the waterproof packing 35 is interposed between the motor 11 and the peripheral edge portion of the opening (see FIG. 1). It is installed. A part of the motor 11 is housed in the gear casing 22. The entire motor 11 may be housed in the gear casing 22.

The end of the first side X1 of the shaft 12 and the worm 15 are housed in the shaft hole 29 of the gear casing 22. The bottom surface 29a of the shaft hole 29 supports the end of the first side X1 of the shaft 12 via the bearing 33.

The shaft hole 29, which is the first accommodating portion, does not penetrate the gear casing 22 in the first direction X, but if a support surface capable of supporting the shaft 12 is formed on the inner surface of the first accommodating portion. , The first accommodating portion may penetrate the gear casing 22.

The shaft hole 30 is formed so as to extend from the outer surface of the gear casing 22 in the second direction Y orthogonal to (intersect) the first direction X and the third direction Z, respectively. As shown in FIG. 1, in this example, the shaft hole 30 does not penetrate the gear casing 22.
As shown in FIG. 4, the shaft hole 30 communicates with the inside of the gear casing 22 such as inside the gear hole 31 via the communication hole 36 formed on the inner peripheral surface of the shaft hole 30. The communication hole 36 opens in the middle portion of the shaft hole 30 in the second direction Y. The shaft hole 30 and the communication hole 36 are holes for adjusting the pressure inside the gear casing 22.
Although the shaft hole 30 does not penetrate the gear casing 22, the shaft hole may penetrate the gear casing 22 in the second direction Y. A semipermeable membrane that allows air to pass through but does not allow water to pass through may be attached to the shaft hole 30.

As shown in FIG. 3, the gear hole 31 is a recess for accommodating the worm wheel unit 25. The gear hole 31 is formed on the side opposite to the shaft hole 30 with respect to the central axis of the shaft hole 29. The gear hole 31 communicates with the shaft hole 29 at the end of the first side X1 of the shaft hole 29.
A support shaft 38 for supporting the worm wheel unit 25 is fixed to the central portion of the bottom surface of the gear hole 31. The support shaft 38 extends in the second direction Y from the bottom surface of the gear hole 31.

As shown in FIGS. 5 and 6, the thrust receiver 23 includes a support member 41, a grease groove (holding portion) 42, an urging portion 43, and a protruding portion 44.
The support member 41 is formed in a rectangular parallelepiped shape. When viewed in the second direction Y shown in FIG. 6, the first side of the support member 41 in the third direction Z has a semicircular shape.
As shown in FIGS. 5 and 6, a notch 41a is formed on the first side of the support member 41 in the third direction Z. The notch 41a penetrates the support member 41 in the first direction X. The notch 41a is open on the first side of the support member 41 in the third direction Z.
As shown in FIG. 5, a through hole 41b is formed at the end of the support member 41 on the second side in the third direction Z. The through hole 41b extends in the second direction Y and penetrates the support member 41 in the second direction Y.
A guide portion 41c is formed at the end of the through hole 41b in the support member 41 in the second direction Y. The guide portion 41c is formed so that the inner diameter gradually increases toward the end in the second direction Y at the end portion of the through hole 41b.

As shown in FIGS. 5 and 6, the grease groove 42 is formed on the outer surface of the support member 41 facing the first side X1 of the first direction X. The grease groove 42 is arranged at the edge of the through hole 41b on the outer surface of the support member 41. The grease groove 42 is arranged on the first side in the third direction Z with respect to the through hole 41b. A lubricating material (not shown) such as grease is held in the grease groove 42. The holding portion may hold the lubricating material by adsorbing the lubricating material or the like.
As shown in FIG. 6, the urging portions 43 are arranged in a pair in the notch 41a of the support member 41 so as to be separated from each other in the second direction Y. The shaft 12 is shown by a two-dot chain line in FIG.
The pair of urging portions 43 are fixed to the second end of the support member 41 in the notch 41a in the third direction Z. The pair of urging portions 43 are arranged so as to be gradually separated from each other toward the first side in the third direction Z.
The number of the urging portions 43 included in the thrust receiver 23 is not particularly limited, and may be one or three or more.

As shown in FIG. 5, the protruding portion 44 is formed in a plate shape with the third direction Z as the thickness direction. The protrusion 44 projects from the outer surface of the support member 41 facing the second side X2 in the first direction X toward the second side X2. The protrusion 44 and the support member 41 are flush with each other on the second side of the third direction Z.
The support member 41, the grease groove 42, the urging portion 43, and the pair of projecting portions 44 constituting the thrust receiver 23 are integrally formed of the same material as the bearing 33.
As shown in FIG. 3, the thrust receiver 23 is arranged in the shaft hole 29 of the gear casing 22.

As shown in FIG. 5, the fixed shaft 24 is formed in a columnar shape by a metal such as stainless steel. As shown in FIG. 6, the outer diameter of the shaft 12 and the width of the notch 41a of the thrust receiver 23 in the second direction Y are about the same.
As shown in FIG. 3, the fixed shaft 24 is arranged in the support member 41 of the gear casing 22 and the thrust receiver 23, respectively. More specifically, the fixed shaft 24 is arranged in the shaft hole 30 of the gear casing 22 and in the through hole 41b of the support member 41, respectively. Therefore, the thrust receiver 23 is fixed to the gear casing 22 in the first direction X by the shaft member 24.
As shown in FIG. 4, the length of the fixed shaft 24 is determined so that the fixed shaft 24 arranged in the shaft hole 30 of the gear casing 22 does not block the communication hole 36 of the gear casing 22.

As shown in FIG. 3, the outer surface of the support member 41 of the thrust receiver 23 facing the first side X1 comes into contact with the end surface of the second side X2 of the worm 15 in the first direction X via the grease groove 42. , This end face is supported from the second side X2 side. The support member 41 of the thrust receiver 23 fixed to the gear casing 22 by the shaft member 24 regulates the worm 15 from moving to the second side X2 with respect to the gear casing 22. The protrusion 44 is in contact with the inner surface (inner surface of the gear casing 22) on the second side of the shaft hole 29 in the third direction Z.
The shaft 12 of the motor 11 is arranged in the notch 41a of the support member 41 (see also FIG. 6). The pair of urging portions 43 urge the shaft 12 to the first side in the third direction Z.

In the worm wheel unit 25, the large-diameter gear 25a and the small-diameter gear 25b are coaxially formed. The large diameter gear 25a is a worm wheel. The type of the small diameter gear 25b is not particularly limited.
The worm wheel unit 25 is arranged in the gear hole 31 and is rotatably supported around the support shaft 38 with respect to the gear casing 22 by the support shaft 38. A plurality of tooth portions of the large-diameter gear 25a are formed around the support shaft 38. The tooth portion of the large diameter gear 25a meshes with the tooth portion of the worm 15 at the position P1. The position P1 is on the side opposite to the fixed shaft 24 with the shaft 12 interposed therebetween, and is located on the first side X1 in the first direction X with respect to the fixed shaft 24.
The positional relationship between the position P1 at which the large-diameter gear 25a and the worm 15 mesh with each other and the fixed shaft 24 is not limited to this.

As shown in FIG. 1, the cover 26 is formed in an annular shape. The cover 26 covers the opening peripheral edge of the gear hole 31 in the gear casing 22. As shown in FIGS. 1 and 2, the small diameter gear 25b of the worm wheel unit 25 projects outward from the hole formed in the center of the cover 26.

The process of inserting the fixed shaft 24 into the thrust receiver 23 when manufacturing the motor 1 with a speed reducer configured as described above will be described.
The gear casing 22 is held so that the first side X1 in the first direction X is downward. The thrust receiver 23 is inserted into the shaft hole 29 of the gear casing 22. At this time, the thrust receiver 23 falls downward with respect to the shaft hole 29.
The through hole 41b of the thrust receiver 23 may not be sufficiently dropped to the position of the shaft hole 30 of the gear casing 22. Even in this case, since the guide portion 41c is formed in the through hole 41b, the fixed shaft 24 is guided into the through hole 41b by the guide portion 41c.

Next, the operation of the motor 1 with a speed reducer configured as described above will be described.
When the motor 11 is driven to rotate the shaft 12 in a predetermined direction, the worm 15 rotates together with the shaft 12. The large-diameter gear 25a of the worm wheel unit 25 that meshes with the worm 15 rotates around the support shaft 38, and torque is output from the small-diameter gear 25b protruding outward from the cover 26. At this time, the direction of the load input from the large-diameter gear 25a is substantially equal to the direction A from the position P1 toward the fixed shaft 24, as shown in FIG.

When the support member 41 receives the load of the second side X2 of the first direction X by the worm 15, the grease groove 42 is arranged on the first side of the third direction Z with respect to the through hole 41b, so that it protrudes. The portion 44 attempts to rotate around the fixed shaft 24 so as to move to the second side of the third direction Z. However, since the protrusion 44 is in contact with the inner surface of the shaft hole 29 on the second side in the third direction Z, rotation is restricted by this inner surface.
Since the thrust receiver 23 is made of an elastic material, when the thrust receiver 23 receives a load, the impact due to the load can be absorbed.

As described above, according to the motor 1 with a speed reducer of the present embodiment, the support member 41 is fixed to the gear casing 22 by the fixed shaft 24. Therefore, the support member 41 can be securely fixed to the gear casing 22. The support member 41 restricts the worm 15 and the shaft 12 from moving to the second side X2 with respect to the gear casing 22, and the bottom surface 29a of the shaft hole 29 of the gear casing 22 restricts the worm 15 and the shaft 12 from moving to the gear casing 22. The shaft 12 is restricted from moving to the first side X1. As described above, the gear casing 22 supports the load acting on both sides of the first side X on the shaft 12 with a simple configuration of the support member 41, the fixed shaft 24, and the bottom surface 29a of the shaft hole 29 of the gear casing 22. be able to.
Since the motor 11 does not need to support the load acting toward the second side X2 of the shaft 12, the connection between the gear casing 22 and the motor 11 can be simplified. Then, the manufacturing cost of the motor 1 with a speed reducer can be reduced, and the weight of the motor 1 with a speed reducer can be reduced.

A shaft hole 30 is formed in the gear casing 22. Therefore, the support member 41 can be supported by the gear casing 22 via the fixed shaft 24 by using the shaft hole 30 for adjusting the pressure inside the gear casing 22.
A grease groove 42 is formed on the outer surface of the support member 41 facing the first side X1. As a result, the lubricant that makes the worm 15 slippery with respect to the support member 41 can be held by the grease groove 42.

A guide portion 41c is formed at the end of the through hole 41b in the support member 41. Therefore, at the time of manufacturing the motor 1 with a speed reducer, the fixed shaft 24 can be guided into the through hole 41b by the guide portion 41c, and the fixed shaft 24 can be easily inserted into the through hole 41b.
The support member 41 is provided with a pair of urging portions 43. Since the shaft 12 rotates in a state of being urged to the first side of the third direction Z, it is possible to suppress the vibration of the shaft 12 and the generation of abnormal noise from the shaft 12 when the shaft 12 rotates. can.

The thrust receiver 23 includes a protrusion 44. Therefore, it is possible to prevent the support member 41 loaded by the worm 15 from rotating around the fixed shaft 24.
The position P1 at which the large-diameter gear 25a and the worm 15 mesh with each other is on the side opposite to the fixed shaft 24 with the shaft 12 interposed therebetween, and is located on the first side X1 with respect to the fixed shaft 24. Since the direction of the load input from the large-diameter gear 25a is substantially equal to the direction from the position P1 toward the fixed shaft 24, the load input from the large-diameter gear 25a can be effectively supported by the fixed shaft 24.

Although one embodiment of the present invention has been described in detail with reference to the drawings, the specific configuration is not limited to this embodiment, and the configuration is changed, combined, or deleted without departing from the gist of the present invention. Etc. are also included.
For example, in the above embodiment, the thrust receiver 23 does not have to include the grease groove 42, the urging portion 43, and the protruding portion 44. The guide portion 41c may not be formed in the through hole 41b of the thrust receiver 23.

1 Motor with reducer 11 Motor 12 Shaft 15 Warm (1st gear)
22 Gear casing (case)
24 Fixed shaft (shaft member)
25a Large diameter gear (worm wheel)
29a Bottom surface (support surface)
30 Shaft hole (accommodation part)
38 Support shaft 41 Support member 41b Through hole 41c Guide part 43 Basis part 44 Protruding part P1 position

Claims (7)

With a motor with a shaft,
The first gear fixed to the outer peripheral surface of the shaft and
A case having a support surface that accommodates at least a part of the motor and the first gear and supports the tip of the shaft.
A support member arranged in the case and supporting the first gear from the base end side of the shaft, and
Shaft members arranged in the front case and the support member, respectively,
Motor with reducer. The motor with a speed reducer according to claim 1, wherein the case communicates with the inside of the case and has a hole in which the shaft member is arranged. The motor with a speed reducer according to claim 1 or 2, wherein a holding portion for holding a lubricant is formed on an outer surface of the support member that supports the first gear. The support member is formed with a through hole in which the shaft member is arranged.
The speed reducer according to any one of claims 1 to 3, wherein a guide portion whose inner diameter gradually increases toward the end of the through hole is formed at the end of the through hole in the support member. motor. The motor with a speed reducer according to any one of claims 1 to 4, wherein the support member is provided with an urging portion for urging the shaft in a direction intersecting the axis of the shaft. The motor with a speed reducer according to any one of claims 1 to 5, further comprising a protruding portion that protrudes from the outer surface of the support member and contacts the inner surface of the case. The first gear is a worm and
The case is provided with a worm wheel that is rotatably supported around a support shaft along a direction intersecting the axis of the shaft and meshes with the worm.
Any of claims 1 to 6, wherein the position where the worm and the worm wheel mesh with each other is on the side opposite to the shaft member across the shaft and is located on the tip end side of the shaft with respect to the shaft member. The motor with a reducer described in item 1.

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