JP2017063613A - Motor device and assembly method of motor device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a motor device in which a force in the radial direction can be prevented from acting on the thrust bearing housing section, when a radial bearing is press fitted in a radial bearing housing section, and to provide an assembly method of a motor device.SOLUTION: In a motor device, a radial bearing 54 is press fitted in a radial bearing housing section 70 and fixed in place. Outer peripheral shape of the radial bearing 54 at a part corresponding to a thrust bearing housing section 62 is formed smaller than the inner peripheral shape of the radial bearing housing section 70. Consequently, when press fitting the radial bearing 54 to the radial bearing housing section 70, a force in the radial direction can be prevented from acting on the thrust bearing housing section 62. Furthermore, this force can be prevented from acting on the thrust bearing 64 housed in the thrust bearing housing section 62.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a motor device that outputs a driving force of a motor.

The motor with a speed reduction mechanism disclosed in Patent Document 1 below is output after the rotation of the rotating shaft is decelerated by a speed reduction mechanism including a worm wheel meshing with the worm. As the worm and the worm wheel mesh, a thrust load acts on the rotating shaft as a reaction force.
In particular, in the case where the rotating shaft rotates forward and backward, this thrust load acts on both shaft ends, that is, both shaft ends of the rotating shafts on the gear housing side and the yoke housing side. Therefore, the thrust load at both shaft ends of the rotating shaft is supported by a thrust bearing structure using a steel ball and a metal thrust plate, respectively.

Also, if there is a clearance between the end face of the rotating shaft and the thrust plate, they collide with each other and an abnormal noise is generated. In particular, when forward and reverse rotation occurs, the direction of rotation of the rotating shaft changes, so that the direction of thrust load action also changes, and the occurrence of the abnormal noise becomes significant.

In order to prevent the generation of this noise, in the thrust bearing structure on the gear housing side, the rotating shaft housing chamber provided in the gear housing and the injection space are partitioned by a thrust plate, and the molten resin material is injected into the injection space and cured. The clearance of the rotating shaft is adjusted by the thermal contraction of the resin material.

JP2011-30346A

By the way, when the thrust plate is disposed in the thrust plate housing portion, the thrust plate is disposed from the worm housing portion side in the thrust plate housing portion formed in a deep and narrow place located further on the axial end side of the worm housing portion. Must-have.
For this reason, it is difficult to properly maintain the posture of the thrust plate until the thrust plate is disposed in the thrust plate housing portion.

In view of the above facts, the present invention has an object to obtain a motor device and a method of assembling the motor device that can easily arrange a plate in pressure contact with the thrust bearing from the opposite side of the rotor shaft in the thrust bearing in an appropriate posture. is there.

  According to a first aspect of the present invention, there is provided a motor device having a rotor that rotates around a rotor shaft when energized, a housing that houses the rotor shaft, and a radial bearing housing portion formed in the housing. A radial bearing that is inserted in the axial direction of the rotor shaft and has a bearing hole into which one axial end side of the rotor shaft enters, and that rotatably supports the rotor shaft that has entered the bearing hole; and A space constituted by the radial bearing housing portion and the plate housing portion that are at least partially inserted into the plate housing portion formed in the housing so as to communicate with the radial bearing housing portion in the axial direction and communicated with each other. Separating the radial bearing housing side and the opposite side in the axial direction of the rotor shaft, and a plate movable in the axial direction; A thrust bearing that is in contact with the rotor shaft on the radial bearing housing portion side and receives axial force in the rotor shaft, and is formed in the radial bearing, communicated with the bearing hole, and opposite to the bearing hole A thrust bearing accommodating portion that is open at an end and can accommodate the thrust bearing, and a filling that is filled in a resin filling portion that communicates with the plate accommodating portion on the side opposite to the radial bearing accommodating portion with respect to the plate In the motor device including the resin material, the radial bearing press-fitted and fixed to the radial bearing housing portion has an outer peripheral shape of a portion corresponding to the thrust bearing housing portion as compared to an inner peripheral shape of the radial bearing housing portion. It is characterized by being formed small.

  In the motor device according to the first aspect of the present invention, a radial bearing housing is formed in a housing in which the rotor shaft of the motor is housed, and the shaft of the rotor shaft is inserted into the bearing hole of the radial bearing inserted into the radial bearing housing. One end of the direction enters. Thereby, the axial direction one end side of a rotor shaft is rotatably supported by a radial bearing.

In addition, a plate accommodating portion is formed in the housing. The plate housing portion communicates with the radial bearing housing portion in the axial direction of the rotor shaft. A plate is provided inside the plate housing portion so as to be movable in the axial direction of the rotor shaft. A space formed by the radial bearing housing portion and the plate housing portion that are in communication with each other is partitioned by the plate into the radial bearing housing portion side and the opposite side in the axial direction of the rotor shaft.

Further, a resin filling portion is formed in the housing. The resin filling portion communicates with the plate housing portion on the side opposite to the radial bearing housing portion with respect to the plate. The resin filling portion is filled with a molten filling resin material and the plate is pressed against the radial bearing housing portion side. Is done. Since the thrust bearing is provided on the radial bearing housing portion side of the plate, the thrust bearing is also pressed. And the axial backlash adjustment in a rotor axis | shaft is appropriately performed by the thermal contraction accompanying the cooling hardening of the filling resin material after filling.

  In the motor device according to the first aspect of the present invention, the radial bearing is provided with a thrust bearing housing portion. The thrust bearing housing portion communicates with the bearing hole and opens on the side opposite to the bearing hole, and the thrust bearing can be housed in the thrust bearing housing portion from the opening. For this reason, the rotor shaft can be made thinner than the thrust bearing.

Furthermore, in the motor device according to the first aspect of the present invention, the radial bearing is press-fitted and fixed to the radial bearing housing portion. Here, the outer peripheral shape of the portion corresponding to the thrust bearing housing portion of the radial bearing is formed smaller than the inner peripheral shape of the radial bearing housing portion. For this reason, when the radial bearing is press-fitted into the radial bearing housing portion, it is possible to prevent a force in the diameter reducing direction from acting on the thrust bearing housing portion, and further this force acts on the thrust bearing housed in the thrust bearing housing portion. Is prevented.

  The motor device according to a second aspect of the present invention is characterized in that, in the motor device according to the first aspect, the thrust bearing is formed in a spherical shape having an outer diameter dimension larger than an inner diameter dimension of the bearing hole.

By the way, in the structure disclosed by patent document 1, until a molten resin material is inject | poured, it is between a thrust plate and a thrust plate so that a steel ball may not fall from the recessed part formed in the front end surface of a rotating shaft. The state accommodated in the recess must be maintained. That is, there is a problem in that the steel ball falls off without being held unless the rotating shaft is maintained in the gear housing. Moreover, since the steel ball is accommodated in the recess of the rotating shaft,
There is also a problem that the rotating shaft needs to have a diameter larger than the diameter of the steel ball.

  In contrast, the thrust bearing of the motor device according to the second aspect of the present invention has a spherical shape whose outer diameter is larger than the inner diameter of the bearing hole formed in the radial bearing. For this reason, the thrust bearing accommodated in the thrust bearing accommodating portion does not pass through the bearing hole of the radial bearing. Thus, when the motor device is assembled, the radial bearing is inserted and fixed in the radial bearing housing portion so that the thrust bearing housed in the thrust bearing housing portion is thrust from the thrust bearing housing portion even when the rotor shaft is not assembled. Since the bearing does not fall off, the assembly work is easy.

  A motor device according to a third aspect of the present invention is the motor device according to the first or second aspect, wherein the thrust bearing is applied to the plate that is most moved to the side opposite to the radial bearing housing portion in the plate housing portion. The distance L6 from the center of the thrust bearing to the axial end of the rotor shaft inserted into the bearing hole is set so as to be larger than the radial dimension R of the thrust bearing. To do.

  According to the motor device of the third aspect of the present invention, the state in which the thrust bearing is moved until the plate is most moved to the side opposite to the radial bearing housing in the plate housing and the thrust bearing is brought into contact with the plate in this state. Then, the dimensions of the radial bearing and the thrust bearing are set so that the distance L6 from the center of the thrust bearing to the axial end of the rotor shaft inserted into the bearing hole is larger than the radial dimension R of the thrust bearing.

For this reason, in this state, even if the rotor shaft of the motor is assembled in the bearing hole of the radial bearing, the thrust force of the rotor shaft does not act on the thrust bearing. Thereby, the damage by the collision with the thrust bearing of the rotor shaft when the rotor shaft is assembled to the radial bearing can be prevented.

  The motor device according to a fourth aspect of the present invention is the motor device according to any one of the first to third aspects, wherein the radial bearing housing portion is disposed between the radial bearing housing portion and the plate housing portion. A reduced-diameter portion that is reduced in diameter toward the plate housing portion is provided.

  Therefore, according to the motor device of the fourth aspect of the present invention, if the plate 68 is positioned at the reduced diameter portion 76 in a state where the radial bearing 54 is press-fitted into the radial bearing housing portion 70, the plate 68 is the plate. By moving to the accommodating portion 78 side, it is guided on the inner peripheral surface of the reduced diameter portion 76 and can be easily fitted into the plate accommodating portion 78. Accordingly, the plate can be stabilized in a predetermined posture before the resin filling portion is filled with the filled resin material.

  According to a fifth aspect of the present invention, there is provided a motor device assembly method comprising: a bearing hole into which a rotor shaft of a motor is inserted; and a thrust bearing that communicates with a tip end side of the bearing hole and from an end opposite to the bearing hole. A thrust bearing housing portion that is open so as to accommodate the thrust bearing, and a thrust bearing and plate mounting step for holding the thrust bearing and the plate in the radial bearing, and a radial bearing housing portion formed in the housing in which the rotor shaft is housed. A plate housing portion that inserts the radial bearing and fixes the radial bearing to the radial bearing housing portion, and that communicates with the radial bearing housing portion in the axial direction of the rotor shaft and accommodates at least a part of the plate. In contrast, a radial bearing assembling step for allowing a part of the plate to enter, and the plate including at least a part for the plate accommodating portion. The radial bearing housing of the plate housing portion in a state in which a space formed by the radial bearing housing portion and the plate housing portion communicated with each other by a seat is partitioned into the radial bearing housing portion side and the opposite side. Thrust interposed between the plate and the axial end portion of the rotor shaft, which is filled with a filling resin material from a resin filling portion communicating with the plate housing portion on the side opposite to the portion, and inserted into the bearing hole And a resin filling step of pressing the plate against the bearing.

  In the method for assembling the motor device according to the fifth aspect of the present invention, the bearing hole into which the rotor shaft of the motor is inserted, and the thrust bearing communicated with the tip end side of the bearing hole from the end opposite to the bearing hole. In a radial bearing having a thrust bearing housing portion that is open so as to be able to be accommodated, the thrust bearing and the plate are held in the thrust bearing and plate mounting step.

On the other hand, a radial bearing accommodating portion corresponding to the radial bearing is formed in the housing that accommodates the rotor shaft of the motor, and further, a plate accommodating portion is provided at the axial front end side of the rotor shaft with respect to the radial bearing accommodating portion. Communicate. In the radial bearing assembling step, the radial bearing is inserted into the radial bearing housing portion, and a part of the plate enters the plate housing portion.

When at least a part of the plate enters the plate housing portion, the space formed by the radial bearing housing portion and the plate housing portion that are in communication with each other is divided into the radial bearing housing portion side and the opposite side (resin filling portion side) by the plate. It is divided into and. In this state, in the resin filling step, the filled resin material melted from the resin filling portion communicating with the plate housing portion on the opposite side of the plate housing portion from the radial bearing housing portion is filled. The filled resin material that has flowed into the plate housing portion from the resin filling portion presses the plate toward the radial bearing housing portion.

A rotor shaft thrust bearing is provided between the axial end of the rotor shaft inserted into the bearing hole of the radial bearing and the plate, and when the filling resin material presses the plate as described above,
The thrust bearing is pressed together with the plate against the end of the rotor shaft in the axial direction, but the filled resin material is cooled and hardened, so that the heat shrinks and the backlash in the axial direction of the rotor shaft is appropriately adjusted.

  Here, in the method for assembling the motor device according to the fifth aspect of the present invention, the radial bearing has a thrust bearing accommodating portion that is open from the end opposite to the bearing hole so that the thrust bearing can be accommodated. Therefore, in the thrust bearing and plate mounting process, the thrust bearing and the plate can be stably held.

  The motor device assembly method according to a sixth aspect of the present invention is the motor device assembly method according to the fifth aspect, wherein the radial bearing has an outer diameter larger than an inner diameter of the bearing hole in the thrust bearing housing portion. When the radial bearing is fixed to the radial bearing accommodating portion in the radial bearing assembling step, the thrust bearing accommodating portion in which the thrust bearing is accommodated is accommodated. The radial bearing is inserted into the radial bearing accommodating portion from the lower side with the opening opposite to the bearing hole facing upward.

  In the motor device assembled by the motor device assembling method of the sixth aspect of the present invention, the thrust bearing has a spherical shape, and the outer diameter is larger than the inner diameter of the bearing hole formed in the radial bearing. Further, in the radial bearing, a thrust bearing accommodating portion is formed in communication with the bearing hole at the tip end side of the bearing hole, and the thrust bearing is accommodated in the thrust bearing accommodating portion.

By the way, in the structure disclosed by patent document 1, until a molten resin material is inject | poured, it is between a thrust plate and a thrust plate so that a steel ball may not fall from the recessed part formed in the front end surface of a rotating shaft. The state accommodated in the recess must be maintained. That is, there is a problem in that the steel ball falls off without being held unless the rotating shaft is maintained in the gear housing. Moreover, since the steel ball is accommodated in the recess of the rotating shaft,
There is also a problem that the rotating shaft needs to have a diameter larger than the diameter of the steel ball.

  On the other hand, in the method of assembling the motor device according to the sixth aspect of the present invention in which the radial bearing or the thrust bearing is used as described above, the opening on the opposite side to the bearing hole of the thrust bearing housing portion faces upward. In this state, the thrust bearing is received from the opening and the above-described plate is held. In this state, in the radial bearing assembly process, the radial bearing is inserted from below relative to the radial bearing housing portion of the housing.

Therefore, the thrust bearing accommodated in the thrust bearing accommodating portion by inserting and fixing the radial bearing in the radial bearing accommodating portion of the housing in the radial bearing assembling step can be accommodated even in a state where the rotor shaft is not assembled. Assembling work is easy without falling off the part. Moreover, the thrust bearing is configured to be held in a thrust bearing housing portion formed in the radial bearing. For this reason, the rotor shaft can be made thinner than the thrust bearing.

  The motor device assembly method according to a seventh aspect of the present invention is the motor device assembly method according to the sixth aspect, wherein the thrust is applied to the plate most moved to the opposite side of the radial bearing housing portion in the plate housing portion. With the bearing in contact, the distance L6 from the center of the thrust bearing to the axial end of the rotor shaft inserted into the bearing hole is set to be larger than the radial dimension R of the thrust bearing; In the rotor shaft inserting step of inserting the rotor shaft into the bearing hole of the radial bearing in a state where the radial bearing is inserted and fixed in the radial bearing housing portion, the bearing hole has a side opposite to the thrust bearing housing portion. The rotor shaft is inserted into the bearing hole from above with the opening facing upward.

  In the motor device assembled by the method of assembling the motor device according to the seventh aspect of the present invention, the plate moves most on the side opposite to the radial bearing housing portion in the plate housing portion until the thrust bearing contacts the plate in this state. When the thrust bearing is moved, the dimensions of the radial bearing and the thrust bearing are such that the distance L6 from the center of the thrust bearing to the axial end of the rotor shaft inserted into the bearing hole is larger than the radial dimension R of the thrust bearing. Etc. are set.

  According to the assembling method of the motor device of the seventh aspect of the present invention in which such a radial bearing or a thrust bearing is used, in the rotor shaft inserting step of inserting the rotor shaft into the bearing hole of the radial bearing, first, the radial bearing assembly In a state where the radial bearing is inserted and fixed in the radial bearing housing portion in the attaching step, the opening on the opposite side to the thrust bearing housing portion in the bearing hole is directed upward. As a result, the plate and the thrust bearing are lowered by their own weight, and the plate moves most on the side opposite to the radial bearing accommodating portion in the plate accommodating portion, and the thrust bearing is placed on the plate.

Next, the rotor shaft is inserted into the bearing hole of the radial bearing. Here, in this state, the distance L from the center of the thrust bearing to the axial end of the rotor shaft inserted into the bearing hole as described above.
6 is larger than the radial dimension R of the thrust bearing. For this reason, even if the rotor shaft is assembled in the bearing hole of the radial bearing, the thrust force of the rotor shaft does not act on the thrust bearing. Thereby, the damage by the collision with the thrust bearing of a rotor axis | shaft can be prevented in a rotor axis | shaft insertion process.

  The motor device assembly method according to an eighth aspect of the present invention is the motor device assembly method according to any one of the fifth to seventh aspects, wherein the resin filling step is performed in a state where the axial direction of the rotor shaft is horizontal. It is performed.

  In the assembling method of the motor device according to the eighth aspect of the present invention, the resin filling step is performed in a state where the axial direction of the rotor shaft is horizontal. For this reason, when the molten filling resin material is filled, the filling resin material is hardly affected by the weight of the rotor, thrust bearing, and plate of the motor. Thereby, while being able to stabilize the attitude | position of the plate pressed by the filling resin material, the filling pressure of the filling resin material can also be made low.

It is sectional drawing of the motor apparatus which concerns on one embodiment of this invention. It is sectional drawing to which the principal part of the motor apparatus which concerns on one embodiment of this invention was expanded. It is the disassembled perspective view which expanded the principal part of the motor apparatus which concerns on one embodiment of this invention. It is a schematic sectional drawing which shows a thrust bearing accommodation process and a plate mounting process. It is a schematic sectional drawing which shows the assembly | attachment process of the radial bearing to a housing. It is a schematic sectional drawing which shows the process of inserting a rotor axis | shaft. It is a schematic sectional drawing which shows a resin filling process.

<Configuration of the present embodiment>
FIG. 1 is a sectional view schematically showing a configuration of a wiper motor 10 as a motor device according to an embodiment of the present invention.

As shown in FIG. 1, the wiper motor 10 includes a motor 12. This motor 12
Includes a motor housing 14 formed of a magnetic material. Motor housing 14
Is formed in a bottomed cylindrical shape opening toward the left side (gear housing side) in FIG. An armature 16 as a rotor (rotor) is accommodated inside the motor housing 14. The armature 16 includes an armature shaft 18 as a rotor shaft. The axial direction of the armature shaft 18 is the opening direction of the motor housing 14 and the opposite direction (the left-right direction in FIG. 1).
It is along. A bearing portion 20 is provided at the bottom of the motor housing 14 so as to face one axial end of the armature shaft 18 (the right end in FIG. 1).

The bearing unit 20 includes a metal plate 22 at the center of the bottom of the motor housing 14.
The plate 22 is made of a metal plate material harder than the main body portion of the armature shaft 18 by quenching or the like. A bottomed cylindrical recess 26 is formed at one end of the armature shaft 18 in the axial direction, and a bearing ball 24 accommodated in the recess 26 is in point contact with the plate 22. The bearing ball 24 has a spherical shape whose diameter is slightly smaller than the inner diameter of the recess 26 of the armature shaft 18.

In addition, a metal plate 25 similar to the plate 22 is housed and fixed at the bottom of the recess 26 provided at one end of the armature shaft 18, and the bearing ball 24 is in point contact. Thereby, the thrust force is received at one axial end of the armature shaft 18. Note that the straight line connecting the two point contact positions between the plates 22 and 25 and the bearing ball 24 is parallel to the axis of the armature shaft 18 and slightly deviated, and the bearing ball 24 rotates with respect to the rotation of the armature shaft 18. While revolving, wear of the plate 22 is suppressed.

A bearing 23 (oil-impregnated bearing) is fixed to the bearing portion 20 of the motor housing 14. By this bearing 23, the outer peripheral portion of the recess 26 of the armature shaft 18 is supported so as to be rotatable around its central axis.

On the other hand, a pair or a plurality of pairs of field magnets 28 facing the north and south poles are provided inside the motor housing 14 so as to face each other via the armature body 30 of the armature 16. The armature 16 rotates around the central axis of the armature shaft 18 by the interaction between the magnetic field formed by the applied winding and the magnetic field formed by the field magnet 28.

As shown in FIG. 1, a worm gear 32 is formed on the armature shaft 18 by rolling or the like on the other end side of the armature shaft 18 (the left side in FIG. 1, ie, the front end side). The other end of the armature shaft 18 including the worm gear 32 enters the inside of a gear housing 42 as a housing connected and fixed to the motor housing 14. The gear housing 42 includes a housing main body 44. A worm accommodating portion 46 is formed in the housing main body 44. The worm housing portion 46 opens in a direction (upward in FIG. 1) perpendicular to the axial direction of the armature shaft 18, and the other end side of the armature shaft 18 enters the worm housing portion 46 and the worm gear 32 is moved. positioned.

Further, in the housing main body 44, a worm wheel housing portion is formed in communication with the worm housing portion 46 on the side of the worm housing portion 46 (the depth side in FIG. 2 or the front side of the paper surface). In the worm wheel housing portion, the worm wheel is rotatably supported around an axis whose axial direction is the opening direction of the housing main body 44 and the opposite direction in a state where the worm wheel is engaged with the worm gear 32.

The worm wheel is directly or indirectly connected to the output shaft, and is further integrally connected to the base end portion of the wiper arm constituting the wiper device. A wiper blade including a blade rubber made of an elastic material such as a rubber material or an elastomer material is connected to the tip of the wiper arm. The blade rubber of the wiper blade wipes the surface of the windshield glass by reciprocatingly rotating around the base end side of the wiper arm, that is, the above-described output shaft in a state of being pressed against the windshield glass as a wiping surface in the vehicle. .

On the other hand, the housing main body 44 is provided with a bearing mechanism 52 corresponding to the other end portion of the armature shaft 18 that has entered the worm housing portion 46.

Here, FIG. 2 shows an enlarged cross-sectional view of the vicinity of the bearing mechanism 52 in FIG. 1, and FIG. 3 shows an exploded perspective view of the enlarged vicinity of the bearing mechanism 52. As shown in these drawings, the bearing mechanism 52 includes a radial bearing 54. The radial bearing 54 includes a cylindrical bearing portion 56. The inner hole of the bearing portion 56 is a bearing hole 58, which is formed coaxially with the bearing portion 56 and is open at both axial ends of the bearing portion 56.

The inner diameter dimension of the bearing hole 58 is substantially equal to the outer diameter dimension on the other end side (front end side) further than the portion where the worm gear 32 is formed on the armature shaft 18 described above (strictly slightly larger). A portion of the armature shaft 18 on the other end side (tip side) further than a portion where the worm gear 32 is formed is fitted into a bearing hole 58 formed in the bearing portion 56, and the bearing portion 5.
6, that is, rotatably supported by the radial bearing 54. The outer diameter of the armature shaft 18 at the other end (tip side) is larger than the outer diameter of the armature shaft 18 at one end by cold forging of the armature shaft 18 or rolling for forming a worm gear. It has a small outer diameter.

A connecting portion 60 is integrally formed continuously from the other end of the armature shaft 18 in the bearing portion 56. Both the outer peripheral shape and the inner peripheral shape of the connecting portion 60 are formed in a cylindrical shape that is substantially coaxial with the bearing portion 56. However, the inner peripheral shape of the connecting portion 60 gradually increases in the inner diameter dimension toward the other end side of the armature shaft 18 in the connecting portion 60 (that is, the side opposite to the bearing portion 56). Further, the outer peripheral shape of the connecting portion 60 gradually decreases in outer diameter toward the other end side of the armature shaft 18 in the connecting portion 60.

On the side opposite to the bearing portion 56 of the connecting portion 60, a bearing ball accommodating portion 62 as a thrust bearing accommodating portion.
Are integrally formed. The bearing ball housing portion 62 has a cylindrical shape whose outer diameter is substantially equal to the outer diameter size of the connection portion 60 on the bearing ball housing portion 62 side, and whose inner diameter is substantially equal to the inner diameter size of the connection portion 60 on the bearing ball housing portion 62 side. Is formed.

A bearing ball 64 as a thrust bearing is housed inside the bearing ball housing portion 62. The bearing ball 64 is formed in a spherical shape whose outer diameter is the same as the outer diameter of the bearing ball 24 described above. Further, the outer diameter of the bearing ball 64 is substantially equal to the inner diameter of the bearing ball housing portion 62 (strictly, slightly smaller), and in a state where the bearing ball 64 is housed in the bearing ball housing portion 62, the bearing ball housing portion 62. The bearing ball 64 is in sliding contact with the inner periphery of the shaft. Further, the outer diameter of the bearing ball 64 is sufficiently larger than the inner diameter of the bearing hole 58, so that the bearing ball 64 cannot pass through the bearing hole 58.

A plate 65 is provided at the other axial end of the armature shaft 18 facing the bearing ball 64. The plate 65 is made of a metal plate harder than the armature shaft 18 by quenching in the same manner as the plates 22 and 25 described above. The plate 65 is in sliding contact with the bearing ball 64 at the other axial end of the armature shaft 18. .

A plate holding portion 66 is formed at the end of the bearing ball housing portion 62 opposite to the connection portion 60. The plate holding portion 66 has a larger inner diameter than the inner diameter of the bearing ball housing portion 62 and is formed in a ring shape coaxial with the bearing ball housing portion 62. A disc-shaped plate 68 can be fitted inside the plate holding portion 66. More specifically, a part of the plate 68 (the base end side of the plate 68 in the axial direction of the armature shaft 18) is fitted into the plate holding portion 66, and the tip end side of the plate 68 accommodates the bearing ball of the radial bearing 54. The plate 68 can be held in a state of protruding from the front end surface of the portion 62. Plate 68 is Plate 2
Similarly to 2 and 25, it is harder than the armature shaft 18 by quenching, and this plate 68 is in sliding contact with the bearing ball 64 from the side opposite to the plate 65.

Here, as shown in FIG. 4D, the distance L1 from the center of the bearing ball 64 to the bottom portion 67 of the plate holding portion 66 in the state where the bearing ball 64 has moved most toward the bearing hole 58 is the bearing ball 64. The dimension of each part of the radial bearing 54 is set so as to be larger than the radial dimension R. Therefore, when the plate 68 is fitted inside the plate holding portion 66 with the bearing ball 64 moved most to the bearing hole 58 side, as shown in FIG.
And held in a separated state.

As shown in FIGS. 2 and 3, the housing main body 44 is formed with a radial bearing accommodating portion 70 that constitutes an insertion hole corresponding to the radial bearing 54. The radial bearing housing portion 70 is a hole that opens toward one side of the armature shaft 18 in the axial direction (the worm housing portion 46 side). The inner peripheral shape of the radial bearing accommodating portion 70 is a circular shape coaxial with the armature shaft 18, and the inner diameter dimension thereof is substantially equal to the outer diameter dimension of the bearing portion 56 in the radial bearing 54.

For this reason, the radial bearing 54 is inserted and fixed in the radial bearing housing 70 by being press-fitted into the radial bearing housing 70. However, in the radial bearing 54, the bearing ball accommodating portion 6
2 has an outer diameter smaller than the inner diameter of the radial bearing accommodating portion 70. Therefore, as shown in FIG. 2, even when the radial bearing 54 is inserted into the radial bearing housing 70 by press-fitting, there is a gap between the outer peripheral portion of the bearing ball housing portion 62 and the inner circumferential portion of the radial bearing housing portion 70. A gap is formed. Further, as shown in FIG. 4C, the bearing ball 64 moves most toward the bearing hole 58 and the bearing ball 64 is moved.
The inner peripheral shape of the radial bearing 54 is set so that the center of the bearing ball 64 is located inside the bearing ball housing portion 62 even if a part of the bearing ball housing portion 62 protrudes to the bearing hole 58 side. .

On the other hand, a reduced diameter portion 76 is formed continuously from the end of the radial bearing housing 70 opposite to the opening end on the worm housing 46 side. The inner peripheral shape of the reduced diameter portion 76 is a circular shape coaxial with the radial bearing accommodating portion 70, and the radial bearing accommodating portion 70 in the reduced diameter portion 76.
The inner diameter dimension at the end on the side is set equal to the inner diameter dimension of the radial bearing accommodating portion 70. However, the inner diameter dimension of the reduced diameter portion 76 gradually decreases toward the opposite side to the radial bearing accommodating portion 70, and the inner diameter dimension of the reduced diameter portion 76 at the end opposite to the radial bearing accommodating portion 70 is a plate. It is set to be substantially equal to the outer diameter dimension of 68 (strictly, slightly larger than the outer diameter dimension of the plate 68).

On the opposite side of the reduced diameter portion 76 from the radial bearing accommodating portion 70, a plate accommodating portion 78 is formed that forms a fitting insertion hole together with the radial bearing accommodating portion 70 and the reduced diameter portion 76. Plate housing part 78
Is formed in a bottomed hole shape that is coaxial with the radial bearing accommodating portion 70 and has a bottom portion on the opposite side of the reduced diameter portion 76. The inner diameter dimension of the plate accommodating portion 78 is set to be approximately equal to the inner diameter dimension of the end portion of the reduced diameter portion 76 on the plate accommodating portion 78 side. Further, the axial dimension of the plate accommodating portion 78 is set to be equal to or greater than the thickness dimension D1 of the plate 68. For this reason, the plate 68 enters the plate accommodating portion 78 coaxially with the plate accommodating portion 78 and can slide in the plate accommodating portion 78 in the axial direction.

Here, as shown in FIG. 2, from the opening end of the radial bearing housing portion 70 opposite to the reduced diameter portion 76 (on the worm housing portion 46 side) to the opening end of the plate housing portion 78 on the reduced diameter portion 76 side. The distance L2 between the opening end of the radial bearing housing portion 70 opposite to the reduced diameter portion 76 (on the worm housing portion 46 side) and the bottom portion 67 of the plate holding portion 66 and the thickness dimension D1 of the plate 68 are as follows. The dimension of each part of the radial bearing 54, the thickness dimension D1 of the plate 68, the radial bearing accommodating part 70, the reduced diameter part 76, and the axial dimension of the plate accommodating part 78 are set so as to be smaller than the sum of these.

Thus, in a state where the radial bearing 54 is inserted into the radial bearing housing portion 70, the distance L4 from the opening end of the plate housing portion 78 on the radial bearing housing portion 70 side to the bottom portion 67 of the plate holding portion 66 (that is, the above-described case). The difference between the distance L2 and the distance L3) is less than the thickness dimension D1 of the plate 68.

In addition, the end of the armature shaft 18 that is inserted into the bearing hole 58 and rotatably supported by the radial bearing 54 from the other axial end (front end) of the plate accommodating portion 78 on the opposite side to the reduced diameter portion 76 ( The distance L5 to the bottom of the plate accommodating portion 78 is the thickness dimension D1 of the plate 68 and the bearing ball 6
4, the dimension of each part of the radial bearing 54, the thickness dimension D1 of the plate 68, and the radial bearing housing 70. The axial dimension of the reduced diameter part 76 and the plate accommodating part 78 is set.

For this reason, as shown in FIGS. 6B and 7A, the plate 68 abuts against the bottom of the plate accommodating portion 78, and the bearing ball 64 abuts against the plate 68 in this state. In the state, the bearing ball 64 is separated in the axial direction of the armature shaft 18 with respect to the other axial end (tip) of the armature shaft 18 (that is, the armature shaft 18 in this state shown in FIG. 7A). The distance L6 from the other axial end to the center of the bearing ball 64 is larger than the radial dimension R of the bearing ball 64)
.

On the other hand, a sprue 92 constituting a resin filling portion is formed in the housing main body 44 corresponding to the bearing mechanism 52. The sprue 92 has a lateral hole 94. The horizontal hole 94 is a hole having a circular cross section along the axial direction of the armature shaft 18, and the inner diameter dimension thereof is set to be sufficiently smaller than the inner diameter dimension of the plate accommodating portion 78. The lateral hole 94 is formed substantially coaxially with respect to the radial bearing accommodating portion 70 and the plate accommodating portion 78, and the lateral hole 94 is opened at substantially the center of the bottom portion of the plate accommodating portion 78 to form the plate accommodating portion 78. Communicate. In other words,
A bottom portion of the plate accommodating portion 78 is formed around the opening of the horizontal hole 94 to the plate accommodating portion 78.

The sprue 92 is provided with a vertical hole 96. The vertical hole 96 has an axial direction in the housing body 44.
The hole is opened in the same direction as the opening direction, and is a hole having a circular cross section along the direction orthogonal to the lateral hole 94. One end of the vertical hole 96 (the lower end in FIG. 2) communicates with the horizontal hole 94. Also,
A nozzle press contact portion 98 is formed in the opening at the other end of the vertical hole 96. The nozzle pressure contact portion 98 has a truncated cone shape or a concave curved surface shape (in the present embodiment, a truncated cone shape) whose inner diameter dimension gradually increases toward the side opposite to the vertical hole 96 (that is, the opening side of the housing main body 44). Then, as shown in FIG. 7, the tip end of the nozzle 114 of the injection molding machine 112 comes into contact, and the filled resin material 116 melted into the sprue 92 is injected (supplied) from the opening of the vertical hole 96.

<Operation and effect of the present embodiment>
Next, an outline of an assembly method of the bearing mechanism 52 in the wiper motor 10 will be described.

(Bearing ball housing process)
In the bearing ball housing step as the thrust bearing housing step, as shown in FIG. 4, a tube holder 132 is used. A cylindrical holding projection 134 is formed on the tube holder 132. The holding projection 134 is set so that the outer diameter dimension is substantially equal to the inner diameter dimension of the bearing hole 58 formed in the radial bearing 54 (strictly, slightly smaller), and the radial bearing 5 with respect to the cylindrical holder 132 is set.
4 is positioned and held. The axial dimension of the holding protrusion 134 is set shorter than the axial dimension of the bearing hole 58. As shown in FIG. 4A, in the bearing ball housing step, the front end side of the holding projection 134 is directed upward in the vertical direction, and the bearing portion 56 of the radial bearing 54 is shown.
The radial bearing 54 is set on the tube holder 132 with the side approaching the holding protrusion 134 of the tube holder 132 coaxially from above.

As shown in FIGS. 4B and 4C, when the holding projection 134 of the tube holder 132 is fitted into the bearing hole 58 of the radial bearing 54, in this state, that is, the radial bearing 54.
The bearing ball 64 from the opening end opposite to the bearing portion 56 of the bearing ball housing portion 62 of the bearing ball housing portion 62.
(The state shown in FIG. 4C). Here, the outer diameter of the bearing ball 64 is the bearing hole 58.
It is sufficiently larger than the inner diameter dimension. For this reason, the bearing ball 64 does not fall through the bearing hole 58, and the bearing ball 64 can be accommodated in the bearing ball accommodating portion 62.

(Plate mounting process)
Next, in the plate mounting step, as shown in FIGS. 4C and 4D, in the state where the bearing ball 64 is housed in the bearing ball housing portion 62, the plate 68 is mounted from the upper side in the vertical direction. 66 (shown in FIG. 4D). Here, as described above, since the bearing ball 64 is moved to the bearing hole 58 side by its own weight, the plate 68 fitted inside the plate holding portion 66 and the bearing ball 64 are separated from each other and the plate 68 is separated. Is retained. Therefore, the state in which the plate 68 held by the plate holding part 66 is held by the plate holding part 66 without being pushed out by the bearing ball 64 is maintained.

Thus, even in a state where the bearing ball 64 is housed in the bearing ball housing portion 62, the axial dimension and the like of the bearing ball housing portion 62 are set so that the bearing ball 64 does not protrude outside the plate holding portion 66. . Thereby, as shown in FIG. 4D, the plate holding portion 66 of the radial bearing 54 is obtained.
The plate 68 is fitted to the radial bearing 54 and the plate 68 is held in a predetermined posture.

In this embodiment, the bearing ball 64 is accommodated in the radial bearing 54 after being set in the tube holder 132. However, the radial bearing 54 in which the bearing ball 64 is accommodated in advance is set in the tube holder 132 and the plate holding portion. A plate 68 may be attached to 66.

(Assembly process of radial bearing 54)
Next, in the assembly process of the radial bearing 54, as shown in FIG.
4 and the radial bearing receiving portion 7 above the radial bearing 54 provided with the plate 68 in the vertical direction.
The housing body 44 is arranged so that 0 is located. In this state, one of the housing main body 44 and the radial bearing 54 is opposed to the other in the radial bearing accommodating portion 70 and the radial bearing 54.
The radial bearing 54 is press-fitted into the radial bearing accommodating portion 70 as shown in FIG.

In the form shown in FIG. 5, the housing main body 44 approaches the radial bearing 54 set on the tube holder 132 from above in the vertical direction, and the radial bearing 54 is press-fitted into the radial bearing accommodating portion 70. However, the cylindrical holder 132 on which the radial bearing 54 is set may be raised to press-fit the radial bearing 54 into the radial bearing accommodating portion 70.

Thus, also in the assembly process of the radial bearing 54, the opening end of the radial bearing 54 opposite to the bearing portion 56 of the bearing ball accommodating portion 62 is directed upward in the vertical direction. For this reason, the bearing ball 64 does not come out of the bearing ball accommodating portion 62 in the assembly process of the radial bearing 54.

Further, as described above, the distance L2 from the opening end of the radial bearing housing portion 70 on the side opposite to the reduced diameter portion 76 (on the worm housing portion 46 side) to the opening end of the plate housing portion 78 on the reduced diameter portion 76 side is The side opposite to the reduced diameter portion 76 in the radial bearing housing portion 70 (the worm housing portion 46).
The distance L3 from the open end of the side) to the bottom 67 of the plate holding portion 66 is smaller than the sum of the thickness dimension D1 of the plate 68.

Therefore, as shown in FIG. 5B, the radial bearing 54 is connected to the radial bearing accommodating portion 7.
When it is press-fitted to a predetermined position within 0, a part of the plate 68 on the side of the plate accommodating portion 78 enters the plate accommodating portion 78. In this state, the armature shaft 18 in the plate 68 is used.
Both end sides along the axial direction are held by the plate holding portion 66 and the plate accommodating portion 78.

Further, as shown in FIG. 6, even when the holding of the plate 68 by the plate holding portion 66 is released, at least a part of the plate 68 can be allowed to enter the plate holding portion 78 (that is, the plate holding portion). It is easy to fit the plate 68 to 78). Accordingly, the plate 68 can be stabilized in a predetermined posture in the plate accommodating portion 78 even in a state before the filling resin material 116 is filled in the resin filling portion.

Further, when the radial bearing 54 is press-fitted into the radial bearing housing portion 70 as described above, a force on the radial axis 54 side (that is, the diameter reduction direction) acts on the radial bearing 54 from the inner peripheral portion of the radial bearing housing portion 70. To do.

Here, as described above, even if the bearing ball 64 moves most to the bearing hole 58 side and a part of the bearing ball 64 protrudes to the bearing hole 58 side from the bearing ball accommodating portion 62, the center of the bearing ball 64 is The inner peripheral shape of the radial bearing 54 is set so as to be located inside the bearing ball housing portion 62. Further, the outer diameter of the bearing ball accommodating portion 62 is smaller than the inner diameter of the radial bearing accommodating portion 70, and a gap is formed between the outer peripheral portion of the bearing ball accommodating portion 62 and the inner peripheral portion of the radial bearing accommodating portion 70. Is done. For this reason, in the state where the radial bearing 54 is press-fitted into the radial bearing housing portion 70, the bearing portion 56 is subjected to a force on the central axis side (that is, the diameter reducing direction) from the inner peripheral portion of the radial bearing housing portion 70. Such a force is prevented from acting on the bearing ball accommodating portion 62. As a result, it is possible to prevent the force during press-fitting from acting on the bearing ball 64 housed in the bearing ball housing portion 62.

(Step of inserting armature shaft 18)
Next, in the insertion step of the armature shaft 18 as the rotor shaft insertion step, the housing body 44 in which the radial bearing 54 is assembled to the radial bearing housing portion 70 is moved in the vertical direction as shown in FIG. Is turned the other way around. As a result, the bearing ball 64 moves downward in the vertical direction within the bearing ball housing portion 62 due to its own weight, and the bottom side of the plate housing portion 78 formed in the housing body 44 by the moved bearing ball 64 pushing down the plate 68. The plate 68 is moved.

Here, as described above, a part of the plate 68 on the side of the plate housing portion 78 enters the plate housing portion 78 in a state where the radial bearing 54 is press-fitted and fixed to the radial bearing housing portion 70. For this reason, if the bearing ball 64 presses the plate 68 toward the bottom side of the plate housing portion 78, the plate 68 can easily enter the plate housing portion 78 and move to the bottom side of the plate housing portion 78. Even if the bearing ball 64 is moved to the plate housing portion 78 side most in the bearing ball housing portion 62 due to the movement of the bearing ball 64 that moves the plate 68 to the bottom side of the plate housing portion 78, the bearing Since the center of the ball 64 is located in the bearing ball housing portion 62, the radial holding state of the bearing ball 64 is maintained.

Further, as shown in FIGS. 6A and 6B, in this state, the other axial end side (tip side) of the armature shaft 18 of the armature 16 is inserted into the housing main body 44 from above in the vertical direction, so that the worm gear 32 is disposed in the worm accommodating portion 46 of the housing main body 44, and FIG.
As shown in (B), the other end side (tip side) of the armature shaft 18 in the axial direction is the radial bearing 5.
4 is inserted into the bearing hole 58.

Here, as described above, from the other end in the axial direction of the armature shaft 18 that is rotatably supported by the radial bearing 54, the end portion opposite to the reduced diameter portion 76 of the plate housing portion 78 (plate housing portion 78. The distance L5 to the bottom) is greater than the sum of the thickness dimension D1 of the plate 68 and twice the radial dimension R of the bearing ball 64 (that is, the diameter dimension of the bearing ball 64). Therefore, in this state, a gap along the axial direction of the armature shaft 18 is formed between the other axial end of the armature shaft 18 and the bearing ball 64. For this reason, when the armature shaft 18 is inserted into the bearing hole 58, the other axial end of the armature shaft 18 is in strong contact with (for example, collides with) the bearing ball 64.
Is prevented from being damaged.

(Resin filling process)
Next, in the resin filling step, as shown in FIG. 7A, the housing main body 4 so that the axial direction of the armature shaft 18 supported by the radial bearing 54 is substantially horizontal with respect to the vertical direction.
4 is rotated. In this state, the vertical hole 96 of the sprue 92 formed in the housing main body 44 extends in the vertical direction (direction perpendicular to the axial direction of the armature shaft 18), and the nozzle pressure contact portion 9
8 opens upward. In this state, as shown in FIG.
8, the nozzle 114 of the injection molding machine 112 is brought into contact with the molten resin material 116, which is injected (supplied) into the sprue 92 as shown in FIG. 7B.

The filled resin material 116 injected into the sprue 92 passes through the vertical hole 96 and the horizontal hole 94, and further passes through the opening of the horizontal hole 94 communicating with the plate housing part 78 and enters the plate housing part 78. The filling resin material 116 that has entered the plate housing portion 78 is partitioned by the plate 68 on the resin filling portion side from the radial bearing housing portion 70 side.
Is pushed to the radial bearing housing part 70 side (opening side of the plate housing part 78) to move the plate 68 from the bottom of the plate housing part 78.

The plate 68 moved in this manner presses the bearing ball 64 and moves together in the bearing ball housing portion 62 to bring the bearing ball 64 into contact with the tip of the armature shaft 18. Thereafter, the filling resin material 116 is cooled and hardened, and an appropriate backlash adjustment in the thrust direction of the armature shaft 18 released from the pressed state by heat shrinkage at that time is performed. Thus, the bearing in the thrust direction (axial direction) of the armature shaft 18 becomes the bearing portion 20 described above.

Here, the filling resin material 116 that has passed through the bottom of the plate accommodating portion 78 from the sprue 92 and entered the plate accommodating portion 78 (that is, between the bottom of the plate accommodating portion 78 and the plate 68) In the periphery of the opening that communicates with the plate accommodating portion 78, the disk becomes a thin disk having a thin thickness. When such a filling resin material 116 is cured, it thermally shrinks at a certain ratio, and the amount of shrinkage is related to the amount of axial play of the armature shaft 18.

Here, the resin shrinks in the thickness direction at a constant ratio with respect to the dimension D2 in the thickness direction of the filling resin material 116 that has entered the plate housing portion 78, but the filling resin material 116 in the plate housing portion 78 as described above. The dimension D2 in the thickness direction is small, and the amount of shrinkage can be made extremely small even when heat shrinks. For this reason, the amount of backlash in the axial direction of the armature shaft 18 can be made extremely small.

In addition, since the opening part (center part) which the horizontal hole 94 and the plate accommodating part 78 communicate becomes thick, since the shrinkage | contraction amount of the axial direction of the armature shaft 18 also becomes large and a hollow arises in the center part, Since the amount of shrinkage is extremely small as described above, the influence on the displacement due to the heat shrinkage of the plate 68 in contact with the surrounding portion is also extremely small.

Further, for example, as shown in FIG. 6, when the filling resin material 116 is filled in a state where the horizontal hole 94 of the sprue 92 is positioned on the lower side in the vertical direction of the plate housing portion 78, the filling resin material 116 forms the horizontal hole 94. It flows upward in the vertical direction and enters the plate accommodating portion 78. In such a case, the filling resin material 116 flows toward the plate accommodating portion 78 against gravity,
The weight of the plate 68 and the bearing ball 64 acts so as to resist the flow of the filled resin material 116.

On the other hand, in the present embodiment, the filling of the housing main body 44 is melted in a state where the armature shaft 18 supported by the radial bearing 54 is rotated so that the axial direction of the armature shaft 18 is substantially horizontal with respect to the vertical direction. The resin material 116 is filled. For this reason, when the filling resin material 116 flows into the plate accommodating portion 78 from the lateral hole 94, the filling resin material 116 is not easily affected by the above-described gravity and the weight of the plate 68 and the bearing ball 64, and smoothly. It can flow into the plate accommodating portion 78.

In the wiper motor 10 manufactured through the manufacturing process including the assembly process as described above, the worm gear 32 is engaged with the worm wheel, and therefore the worm gear 32 receives a reaction force along the axial direction of the armature shaft 18 from the worm wheel. . In addition, when the motor 12 is switched from the forward drive to the reverse drive and from the reverse drive to the forward drive, the direction of the reaction force received by the worm gear 32 from the worm wheel is also reversed.

Here, in the wiper motor 10, the bearing balls 24, 6 are provided at both axial ends of the armature shaft 18.
4 and plates 22, 25, 65, 68 are provided. Here, since the worm gear 32 meshes with the worm wheel, even if the worm gear 32 receives a reaction force along one of the axial directions of the armature shaft 18 or the other from the worm wheel, the armature shaft 18.
The displacement of the worm gear 32 along the axial direction can be suppressed, and the generation of abnormal noise caused by the displacement of the armature shaft 18 in the axial direction can be suppressed.

In the present embodiment, the bearing ball 64 constituting the thrust bearing at the other axial end of the armature shaft 18 is accommodated in the bearing ball accommodating portion 62 of the radial bearing 54, and this radial bearing 54.
Is press-fitted into a radial bearing accommodating portion 70 formed in the housing main body 44. For this reason, unlike the configuration in which the armature shaft 18 accommodates the bearing ball 64 as a thrust bearing, it is not necessary to make the outer diameter dimension of the armature shaft 18 larger than the diameter dimension of the bearing ball 64, so that the armature shaft 18 is formed thin. it can.

For example, the outer diameter of the armature shaft 18 on the other end side (tip side) is the armature shaft 18.
When the outer diameter dimension is smaller than the outer diameter dimension at one end side of the armature shaft 18 due to the cold forging process or the rolling process for forming the worm gear, the bearing ball 6 is placed on the armature shaft 18.
4 is applied to one end side and the other end side of the armature shaft 18, bearing balls having different diameters are used on the one end side and the other end side. Therefore, the motor 1 as in this embodiment
In the case of a wiper motor that normally and reversely drives 2, there is a problem that the rotational loss due to the thrust bearing differs between forward rotation and reverse rotation.

However, in the present embodiment, it is necessary to make the outer diameter dimension of the armature shaft 18 larger than the diameter dimension of the bearing ball 64 even if the outer diameter dimension on the other end side (tip side) of the armature shaft 18 is smaller than the one end side. Therefore, the diameter dimension of the bearing ball 24 on one end side and the bearing ball 64 on the other end side can be made substantially the same. As a result, the rotation loss caused by the bearing in the thrust direction is substantially the same between the normal rotation drive and the reverse rotation drive in the forward rotation and reverse rotation drive as described above, and the fluctuation of the wiper operation during the forward rotation and the reverse rotation is suppressed. Can contribute.

In the present embodiment, the distance L2 from the opening end of the radial bearing housing portion 70 opposite to the reduced diameter portion 76 to the opening end of the plate housing portion 78 on the reduced diameter portion 76 side is set as the radial bearing 5.
The bottom portion 67 of the plate holding portion 66 from the end of the fourth bearing portion 56 opposite to the connection portion 60.
Is set to be smaller than the sum of the distance L3 and the thickness dimension D1 of the plate 68, whereby the radial bearing 54 is press-fitted into the radial bearing accommodating portion 70, thereby the plate 68.
A part of the plate was inserted into the plate accommodating portion 78.

However, the above-described interval L2 may be larger than the sum of the interval L3 and the thickness dimension D1 of the plate 68. That is, when the radial bearing 54 is press-fitted into the radial bearing accommodating portion 70 in a state where the reduced diameter portion 76 constitutes a part of the plate accommodating portion 78 and the plate 68 is retained by the plate retaining portion 66, the plate 68 is An appropriate posture for fitting into the accommodating portion 78 may be maintained and guided into the plate accommodating portion 78. In this way, if the plate 68 is positioned at the reduced diameter portion 76 of the plate housing portion 78 in a state where the radial bearing 54 is press-fitted into the radial bearing housing portion 70, the plate 68 moves to the plate housing portion 78 side. As a result, it is guided on the inner peripheral surface of the reduced diameter portion 76 and can be easily fitted into the plate accommodating portion 78.

In the present embodiment, the present invention is applied to the wiper motor 10. However, the present invention is not limited to the wiper motor 10, and the thrust bearing at the at least one end of the rotor shaft of the motor is described above. What is necessary is just to be the structure which did.

Therefore, for example, the present invention may be applied to a power window device for raising and lowering a door glass of a vehicle with a driving force of a motor. Further, the present invention may be applied to a sunroof device or moon roof device that opens and closes an opening by moving a skylight that closes the opening formed in the roof portion of the vehicle with the driving force of a motor. Furthermore, the present invention may be applied to a seat slide device for moving a vehicle seat in the vehicle front-rear direction with the driving force of the motor, a reclining device for tilting the seat back of the seat with the driving force of the motor, or the like.

DESCRIPTION OF SYMBOLS 10 ... Wiper motor (motor apparatus), 12 ... Motor, 14 ... Motor housing, 16 ... Armature (rotor), 18 ... Armature shaft (rotor shaft), 20
..Bearing part, 22 ... plate, 23 ... bearing, 24 ... bearing ball, 25 ... plate, 26 ... recess, 28 ... field magnet, 30 ... armature Body, 32 ...
Worm gear, 42 ... gear housing, 44 ... housing body, 46 ... worm housing part, 52 ... bearing mechanism, 54 ... radial bearing, 56 ... bearing part, 58
..Bearing hole, 60... Connection portion, 62... Bearing ball housing portion (thrust bearing housing portion), 64
... Bearing ball (thrust bearing), 65 ... Plate, 66 ... Plate holding part, 68
... Plate, 70 ... Radial bearing housing, 76 ... Reduced diameter portion, 78 ... Plate housing, 92 ... Sprue (resin filling portion), 94 ... Side hole (resin filling) Part), 96
..Vertical hole (resin filling part), 98 ... Nozzle pressure contact part, 112 ... Injection molding machine, 114
..Nozzle, 116 ... filling resin material, 132 ... cylinder holder, 134 ... holding projection,

Claims (8)

A motor having a rotor that rotates around the rotor shaft when energized;
A housing that houses the rotor shaft;
Inserted in the axial direction of the rotor shaft with respect to a radial bearing housing portion formed in the housing, has a bearing hole into which one axial end side of the rotor shaft enters, and rotates the rotor shaft that enters the bearing hole Radial bearings to support freely,
The radial bearing accommodating portion and the plate accommodating portion that are at least partially inserted into the plate accommodating portion formed in the housing so as to communicate with the radial bearing accommodating portion in the axial direction of the rotor shaft and communicate with each other. Partitioning the radial bearing housing portion side and the opposite side thereof in the axial direction of the rotor shaft, and a plate movable in the axial direction;
A thrust bearing that receives axial force on the rotor shaft in contact with the rotor shaft on the radial bearing housing side of the plate;
A thrust bearing housing that is formed in the radial bearing, communicates with the bearing hole and is open at an end opposite to the bearing hole and is capable of housing the thrust bearing;
A filling resin material filled in a resin filling portion communicating with the plate housing portion on the side opposite to the radial bearing housing portion with respect to the plate;
In a motor device comprising:
In the radial bearing press-fitted and fixed to the radial bearing housing portion, an outer peripheral shape of a portion corresponding to the thrust bearing housing portion is formed smaller than an inner peripheral shape of the radial bearing housing portion. .   2. The motor device according to claim 1, wherein the thrust bearing is formed in a spherical shape having an outer diameter dimension larger than an inner diameter dimension of the bearing hole.   The axial direction of the rotor shaft inserted into the bearing hole from the center of the thrust bearing in a state where the thrust bearing is in contact with the plate that is most moved to the opposite side of the radial bearing housing in the plate housing The motor device according to claim 1 or 2, wherein a distance L6 to the end is set to be larger than a radial dimension R of the thrust bearing.   4. A reduced diameter portion is provided between the radial bearing accommodating portion and the plate accommodating portion. The reduced diameter portion decreases in diameter from the radial bearing accommodating portion toward the plate accommodating portion. The motor apparatus in any one of. A bearing hole into which the rotor shaft of the motor is inserted; and a thrust bearing housing portion that communicates with the tip end side of the bearing hole and that is open from the end opposite to the bearing hole so that the thrust bearing can be accommodated. A thrust bearing and plate mounting step for holding the thrust bearing and plate in the radial bearing;
The radial bearing is inserted into a radial bearing accommodating portion formed in a housing in which the rotor shaft is accommodated to fix the radial bearing in the radial bearing accommodating portion, and the radial bearing accommodating portion in the axial direction of the rotor shaft A radial bearing assembling step for allowing a part of the plate to be inserted into a plate accommodating portion that is capable of accommodating at least a part of the plate in communication with
A state in which a space formed by the radial bearing housing portion and the plate housing portion that are communicated with each other by the plate, at least a part of which has entered the plate housing portion, is partitioned between the radial bearing housing portion side and the opposite side. An axial end of the rotor shaft inserted into the bearing hole by filling a filling resin material from a resin filling portion communicating with the plate housing portion on the side opposite to the radial bearing housing portion of the plate housing portion A resin filling step of pressing the plate against a thrust bearing interposed between a portion and the plate;
A method for assembling a motor device, comprising: The radial bearing accommodates the thrust bearing formed in a spherical shape having a larger outer diameter than the inner diameter of the bearing hole in the thrust bearing housing portion;
When the radial bearing is fixed to the radial bearing housing portion in the radial bearing assembling step, the opening on the opposite side to the bearing hole of the thrust bearing housing portion in which the thrust bearing is accommodated faces upward. The motor device assembling method according to claim 5, wherein the radial bearing is inserted into the radial bearing housing portion from below relatively in a state. The axial direction of the rotor shaft inserted into the bearing hole from the center of the thrust bearing in a state where the thrust bearing is in contact with the plate that is most moved to the opposite side of the radial bearing housing in the plate housing The distance L6 to the end is set to be larger than the radial dimension R of the thrust bearing,
In the rotor shaft inserting step of inserting the rotor shaft into the bearing hole of the radial bearing in a state where the radial bearing is inserted and fixed in the radial bearing housing portion, the bearing hole has a side opposite to the thrust bearing housing portion. The motor device assembling method according to claim 6, wherein the rotor shaft is inserted into the bearing hole from above with the opening facing upward.   The motor device assembling method according to claim 5, wherein the resin filling step is performed in a state where an axial direction of the rotor shaft is horizontal.

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