JPH0578173U - Wiper motor - Google Patents

Abstract

(57) [Summary] [Purpose] By simplifying the quality control during production,
A wiper motor capable of absorbing a thrust load with an extremely simple structure. [Structure] Armature shaft 3 with gear case 9
a thrust block 15 that is movably supported along the lengthwise direction of a and that contacts one end of the armature shaft 3a in a point contact and the other contact a damper member 16; The wiper motor 1 is provided with an elastic damper member 16 that is in contact with the gear case 9 on the other side and absorbs the thrust load of the armature shaft 3a via the thrust block 15.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a wiper motor used for wiping a wiping surface with a wiper blade, for example.

[0002]

[Prior Art]

 As a wiper motor for wiping the wiping surface with a wiper blade, the one shown in FIG. 3 is known.

The illustrated wiper motor 50 has an armature 52 housed in a motor yoke 51. The armature 52 has an armature shaft 52a. The armature shaft 52a is connected to an armature coil 52b at approximately the center thereof. A commutator 52c is provided, and a sphere 52d is rotatably housed on the base end side which is the left side in the figure of the armature shaft 52a.

A worm 52e is formed near the tip on the right side of the armature shaft 52a in the drawing, and a support projection 52f having a substantially hemispherical shape is provided on the tip side of the armature shaft 52a.

A motor yoke side bearing 53, which is a sliding bearing, is mounted on the left end side of the motor yoke 51 in the figure, and a metal abutment plate 54 corresponding to the motor yoke side bearing 53 is attached. Is fixed, and the base end side of the armature shaft 52a is inserted into the bearing 53 on the motor yoke side with the spherical body 52d being in contact with the contact plate 54.

A magnet 55 is mounted inside the motor yoke 51, and a yoke mounting portion 56 a provided on the left end side of the gear case 56 in the drawing is provided in the opening 51 b on the right end side of the motor yoke 51 in the drawing. It is assembled by screwing a screw (not shown).

A shaft hole 56b formed as a substantially cylindrical opening from the left side to the right side in the drawing is provided at substantially the center of the gear case 56, and the armature shaft is provided in the shaft hole 56b. The front end side of 52a is inserted.

A holder base 57 having a commutator hole 57a in the center is fixed to the yoke mounting portion 56a of the gear case 56 by screwing a screw 58, and the holder base 57 is arranged on the holder base 57. The brushes 59, 59 are pressed against the commutator 52c. External connection wires 60, 60 are connected to the brushes 59, 59.

A gear case side bearing 61, which is a rolling bearing, is mounted on the yoke mounting portion 56a side of the shaft hole 56b of the gear case 56, and a shaft hole 56b corresponding to the gear case side bearing 61 is shown. On the right end side of the inside, an inclined surface 56c is formed which is inclined so as to approach the armature shaft 52a as it goes downward in FIG.

A thrust block 64 is inserted between the support protrusion 52f of the armature shaft 52a and the inclined surface 56c. In the thrust block 64, the inclined gear case contact surface 64a provided on one side is brought into contact with the inclined surface 56c of the gear case 56, and the shaft contact surface 64b provided on the other side is brought into contact with the support protrusion 52f. In addition, the pressing spring 65, which is a torsion coil spring provided between the side portion of the thrust block 64 and the shaft hole 56b, is used to direct the armature shaft 56a downward in the axial direction. The thrust gap is set so that the shaft contact surface 64b is constantly in pressure contact with the support protrusion 52f by the elastic force of the pressing spring 65.

A round-hole-shaped worm wheel storage portion 56d is provided on the lower side of the shaft hole 56b in the drawing, and an output shaft 62 is rotatably provided at the center of the worm wheel storage hole 56d. The wiper blade is supported and is connected to the output shaft 62 via a link (not shown).

A worm wheel 63 is concentrically fixed to the output shaft 62, and the worm wheel 63 meshes with the worm 52e of the armature shaft 52a.

Therefore, when power is supplied from the external connection terminals 60, 60 to the commutator 52c via the brushes 59, 59, the armature coil 52b is excited and electromagnetic induction between the armature 52 and the magnet 55 causes the armature 52 to move. Rotates.

Since the armature shaft 52a is rotated by the rotation of the armature 52, the worm wheel 63 that meshes with the worm 52e is rotated, and the rotation of the worm wheel 63 rotates the output shaft 62. Activate the ipa blade.

At this time, when a large load that prevents the operation of the wiper blade is generated, the load acts as a thrust load that moves the worm 52e through the worm wheel 63 along the axial direction of the armature shaft 52a. When the armature shaft 52a is moved to the right in the figure, the thrust block 64 resists the elastic force of the pressing spring 65 due to the load of the armature shaft 52a moving to the right in the figure. Since the gear case 56 moves to the upper side in the figure along the inclined surface 56c, the amount of movement of the armature shaft 52a due to the thrust load is absorbed in the direction perpendicular to the direction in which the thrust load is applied.

When the armature shaft 52a moves back, the thrust block 64 moves downward in the figure along the inclined surface 56c of the gear case 56 by the elastic force of the pressing spring 65, so that the support projection of the armature shaft 52a is moved. It is pressed against 52f to be in a returning state.

[0017]

[Conventional drawback]

 However, in the wiper motor 50 described above, the thrust load of the armature shaft 52a is absorbed by the movement of the thrust block 65 in the direction perpendicular to the direction of the thrust load, so that the armature from the inclined surface 56c of the gear case 56 is absorbed. It is necessary to set the dimensional accuracy up to the support projection 52f of the shaft 52a to be high, and it is necessary to increase the processing accuracy of the gear case contact surface 64a of the thrust block 64 and the inclined surface 56c of the gear case 56. Further, since the spring rate of the pressing spring 65 has to be set in accordance with the value of the thrust load, there is a problem that accuracy control is difficult when manufacturing each component.

[0018]

[Problems to be solved by the device]

 The problem to be solved is that if the thrust load of the armature shaft is absorbed in the direction perpendicular to the direction of the thrust load, accuracy control during manufacturing becomes difficult.

[0019]

[Means for Solving the Problems]

 The wiper motor according to the present invention is movably supported by the gear case along the length direction of the armature shaft and simplifies the accuracy control during manufacture. A rigid thrust block that contacts the damper member, and an elastic damper that contacts the thrust block on the one hand and the gear case on the other hand and absorbs the thrust load of the armature shaft via the thrust block. The present invention is characterized in that the structure is provided with a member, and in a more preferable embodiment, the thrust block is integrally vulcanized and bonded to the damper member, which simplifies accuracy control during manufacturing. By doing so, it is possible to absorb the thrust load with an extremely simple structure. It was realized the purpose of providing that the wiper motor.

[0020]

In the wiper motor according to the present invention, the damper member that comes into contact with the thrust block on the one hand and the gear case on the other hand is such that the thrust block is along the length direction of the armature shaft due to the thrust load of the armature shaft. When it moves toward, it elastically deforms to absorb the thrust load, and elastically returns when the thrust load disappears. Therefore, it is not necessary to set the dimensional accuracy from the inclined surface of the gear case to the support protrusion of the armature shaft to be high, and it is not necessary to increase the processing accuracy between the contact surface of the gear case and the inclined surface. It is not necessary to set the spring rate of the pressure spring according to the weight value.

[0021]

【Example】

 1 and 2 show an embodiment of a wiper motor according to the present invention.

In the illustrated wiper motor 1, an armature 3 is housed in a motor yoke 2 having a cylindrical shape with a bottom, and an armature shaft 3 a of the armature 3 has an armature coil 3 c wound around an iron core 3 b at substantially the center thereof. And a commutator 3d connected to a part of the armature coil 3c.

On the base end side, which is the left side of the armature shaft 3a in the figure, a sphere 4 for supporting the armature shaft, which is made of metal, is housed in a rotatable state. A worm 3e is formed near the tip on the right side, and a convex portion 3f having a substantially hemispherical shape is provided on the tip side of the armature shaft 3a.

At the center of the closed portion 2a on the left end side of the motor yoke 2 in the figure, a bearing 6 on the side of the motor yoke, which is a slide bearing, is mounted and is made to correspond to the bearing 6 on the side of the motor yoke. A metal contact plate 7 is provided, and the base end side of the armature shaft 3a is inserted into the bearing 6 on the motor yoke side in a state where the spherical body 4 is in contact with the contact plate 7. Therefore, the base end side of the armature shaft 3a is rotatably supported by the bearing 6 on the motor yoke side.

A magnet 8 is mounted inside the motor yoke 2, and a yoke mounting portion 9 a provided on the left end side of the gear case 9 in FIG. 1 is provided in an opening 2 b on the right end side of the motor yoke 2 in the figure. Is assembled by screwing a screw (not shown).

A shaft hole 9b formed as a substantially cylindrical opening from the left side to the right side in FIG. 1 is provided substantially in the center of the gear case 9, and the armature shaft is provided in the shaft hole 9b. The tip side of 3a is inserted.

A holder base 10 having a round hole 10a having an inner diameter larger than the outer diameter of the commutator 3d in the center of the yoke mounting portion 9a of the gear case 9 is screwed with a screw 11. The brushes 12 and 12 are fixed and disposed at positions facing each other with the commutator 3d of the holder base 10 in the center so as to be capable of press-contacting the commutator 3d. The external connection wirings 13, 13 are connected to the.

A gear case side bearing 14, which is a rolling bearing, is mounted in the shaft hole 9b on the yoke mounting portion 9a side of the gear case 9, and the armature shaft 3a is provided on the right end side of the shaft hole 9b in FIG. An end wall 9b1 formed in a flat shape is provided so as to be directly oriented with respect to the axial direction of, and a flat side wall 9b2 is provided along the axial direction of the armature shaft 3a.

A circular worm wheel storage portion 9c is provided below the shaft hole 9b of the gear casing 9 in FIG. 1, and the output shaft is provided at the center of the worm wheel storage hole 9c. A wiper blade 17 is rotatably supported and is connected to the output shaft 17 via a link (not shown).

A worm wheel 18 is concentrically fixed to the output shaft 17, and the worm wheel 18 meshes with the worm 3e of the armature shaft 3a.

In the armature shaft 3a, the convex portion 3f projects in the shaft hole 9b with a slight clearance from the end wall 9b1, and the thrust block 15 is provided between the convex portion 3f and the end wall 9b1. And a damper member 16 is provided.

As is clear from FIG. 2, the thrust block 15 is rectangular and plate-shaped, and is made of a metal having excellent wear resistance as a raw material. The thrust block 15 has one armature shaft contact surface 15a and the other damper member contact surface 15b along the axial direction of the armature shaft 3a.

The damper member 16 has an approximate shape in which the width dimension is larger than that of the thrust block 15, and is made of an elastic body. One of the damper members 16 is a thrust block contact surface 16a along the axial direction of the armature shaft 3a, and the other is a gear case contact surface 16b. The damper member 16 is a thrust block contact surface 16a. Is integrally molded with the thrust block 15 by vulcanizing and adhering to the damper member contact surface 15b of the thrust block 15. As a result, the thrust block 15 is moved while being elastically deformed by the damper member 16 while being supported by the side wall 9b2 of the gear case 9.

Here, the damper member 16 is housed between the armature shaft 3a and the end wall 9b1 in a state of being slightly elastically deformed along the axial direction of the armature shaft 3a, and the damper member 16 has a gear case contact surface. Since the armature shaft contact surface 15a of the thrust block 15 contacts the convex portion 3f of the armature shaft 3a in a state in which 16b is in contact with the end wall 9b1 of the gear case 9, the damper block 16 has the elastically deformed damper member 16. The elastic repulsive force (elastic energy) is made to correspond to the thrust gap setting value.

Further, since the damper member 16 is elastically deformed, the armature shaft contact surface 15a of the thrust block 15 is elastic with respect to the convex portion 3f of the armature shaft 3a corresponding to the thrust gap setting value. Pressed by repulsive force.

In the wiper motor 1 having such a structure, when power is supplied to the commutator 3d from the external connection terminals 13 and 13 via the brushes 12 and 12, the armature coil 3c is excited and the magnet 8 and the magnet 8 are connected to each other. The armature 3 rotates due to the electromagnetic induction action at.

When the armature 3 rotates, the armature shaft 3a rotates while the convex portion 3f rotates in point contact with the thrust block 15 by the elastic repulsive force corresponding to the thrust gap setting value and meshes with the worm 3e. Since the output shaft 17 is rotated by the rotational power of the worm wheel 18, the wiper blade is operated via the above-mentioned link.

At this time, when a large load that prevents the operation of the wiper blade is generated, the load acts as a thrust load that moves the worm 3e through the worm wheel 18 along the axial direction of the armature shaft 3a. Then, when the armature shaft 3a is moved rightward in FIG. 1, the thrust block 15 is pushed and moved rightward in FIG. 1 by the convex portion 3f of the armature shaft 3a. When the thrust block 15 moves to the right side in FIG. 1, the damper member 16 elastically deforms and absorbs the thrust load.

When the thrust load of the armature shaft 3a is removed, the armature shaft 3a moves back to the left side in FIG. 1, and at the same time, the damper member 16 elastically returns to move the thrust block 15 to the armature shaft 3a. Since the convex portion 3f is pressed against the convex portion 3f by the elastic repulsive force corresponding to the thrust gap setting value, the convex portion 3f and the thrust block 15 return to the steady state.

Further, even if the thrust block 15 is worn by pressure contact with the convex portion 3f of the armature shaft 3a due to long-term use, the damper member 16 is elastic along the axial direction of the armature shaft 3a. Since it is set in a deformed state, the shortage due to the wear is compensated for by elastic recovery, so that the thrust gap set value is maintained.

[0041]

[Effect of the device]

 As described above, the wiper motor according to the present invention is movably supported by the gear case along the length direction of the armature shaft, and is in point contact with the tip of the armature shaft on the one hand and the damper on the other hand. A rigid thrust block that abuts the member and an elastic damper member that abuts the thrust block on one side and the gear case on the other side and absorbs the thrust load of the armature shaft via the thrust block Because of the configuration, the thrust load of the armature shaft absorbs the thrust load due to the elastic deformation of the damper member as the thrust block moves along the length direction of the armature shaft, and when the thrust load disappears, the elasticity of the damper member disappears. Thrust gap established by return Since the value is maintained, it is not necessary to set the dimensional accuracy from the inclined surface of the gear case to the support protrusion of the armature shaft as high as compared with the conventional one, and the contact surface of the gear case and the inclined surface Since it is not necessary to increase the processing accuracy and it is not necessary to set the spring rate of the pressing spring according to the value of the thrust load, it is possible to simplify the accuracy control during manufacturing and to use an extremely simple structure. It has an excellent effect of being able to absorb the thrust load.

[Brief description of drawings]

FIG. 1 is a partially cutaway side view of an embodiment of a wiper motor according to the present invention.

2 is an external perspective view of an end portion of an armature shaft in the wiper motor shown in FIG.

FIG. 3 is a partially cutaway side view of a conventional wiper motor.

[Explanation of symbols]

 1 wiper motor 2 motor yoke 3 armature 3a armature shaft 3e worm 6 bearing (bearing on motor yoke side) 9 gear case 14 bearing (bearing on gear casing side) 15 thrust block 16 damper member 17 output shaft 18 worm wheel

Claims (2)

[Scope of utility model registration request] 1. A gear case equipped with an armature, a motor yoke equipped with a bearing for supporting a base end side of an armature shaft included in the armature, and a bearing fixed to the motor yoke and supporting a part of the armature shaft near a tip end thereof. A wiper motor having an output shaft rotatably housed in the gear case, and a worm wheel concentrically fixed to the output shaft and meshing with a worm formed on the armature shaft, A rigid thrust block that is movably supported along the one side and that abuts the tip of the armature shaft in point contact and the other side abuts on the damper member; Touch and in front A wiper motor comprising the elastic damper member that absorbs a thrust load of an armature via the thrust block. 2. The wiper motor according to claim 1, wherein the thrust block is integrally vulcanized and bonded to the damper member.