JP2008238929A - Wiper motor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent degradation of assembly work efficiency by reducing the working man-hours and the weight of a wiper motor. <P>SOLUTION: In a wiper motor having a gear unit 20 which is stored in a bottom gear case 21 connected to a motor unit 10 having an electric motor 11, and converts the rotation of a rotary shaft 12 of the electric motor 11 in a decelerating and rocking manner and transmits the converted rotation to a wiper shaft 31, a resin-made holding member 40 for rotatably supporting the wiper shaft 31 is provided to cover a part of an opening surface of the gear case 21, and a bracket 50 for covering the remaining part of the opening surface of the gear case 21 is provided adjacent to the holding member 40. Fitting parts 51, 52, 53 are provided on the bracket 50. The gear case 21 is formed of aluminum die casting, and a connector 33 is arranged on a bottom wall of the gear case 21. Cutting of the gear case can be omitted, the weight of the bracket can be reduced, and the shape, the structure and the wiring layout can be simplified. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a wiper motor, for example, a technique effective when used in a rear wiper device of an automobile.

A wiper motor used in a rear wiper device of an automobile includes a motor unit having an electric motor and a gear case connected to the motor unit, which reduces the rotation of the rotating shaft of the electric motor and converts it into a swinging motion to obtain a wiper shaft. Some have a gear portion having a speed reducer for transmitting to a bracket and a bracket covering the opening of the gear case.
In such a wiper motor, the gear case is integrally formed by aluminum die casting, the bracket is pressed using an iron plate, and the wiper shaft is rotatably supported by the gear case. For example, see Patent Document 1.
JP 2000-341906 A

Such a rear wiper device has the following problems because the wiper shaft is rotatably supported by a gear case made of aluminum die cast.
(1) Since it is necessary to cut the wiper shaft support portion of the gear case made of aluminum die cast, the number of processing steps increases.
(2) Since the entire surface of the gear case opening is covered with the iron bracket, the amount of iron used increases and the weight increases.
(3) Since it is necessary to arrange the connector insertion port on the vehicle interior side, since the connector insertion port is formed in the iron bracket, the shape becomes complicated.

  An object of the present invention is to provide a wiper motor that can reduce the number of processing steps and weight, and can prevent a reduction in assembly workability.

Typical means for solving the above-described problems are as follows.
(1) a motor unit having an electric motor;
A power transmission unit housed in a bottomed gear case coupled to the motor unit and transmitting the rotation of the rotating shaft of the electric motor to an output shaft;
An output shaft holding member made of resin that covers the opening of the gear case and rotatably supports the output shaft;
A bracket that is adjacent to the output shaft holding member and covers an opening of the gear case;
Wiper motor with
(2) The wiper motor according to (1), wherein a connector is disposed on a bottom wall of the gear case.

According to the above (1), since the output shaft is rotatably held by the resin output shaft holding member, the gear case can be cut and the weight of the bracket is reduced by the amount of the output holding member. be able to.
According to the above (2), since the connector is arranged on the bottom wall of the gear case, the shape and structure and the wiring layout can be simplified.

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

In the present embodiment, the wiper motor according to the present invention is configured as a wiper motor used in a rear wiper device.
As shown in FIGS. 1 to 5, the wiper motor 1 includes a motor unit 10 having an electric motor 11 and a gear unit 20 having a worm gear reduction device 22 as a power transmission unit. And the gear portion 20 are arranged next to each other and fastened by bolts.

As shown in FIG. 5, the rotating shaft (armature shaft) of the electric motor 11 is inserted into a gear case 21 having a bottom portion of the gear portion 20 and is rotatably supported. A worm 13 is formed on the surface.
A worm wheel 23 of a worm gear reduction device 22 is meshed with the worm 13, and the worm wheel 23 is arranged substantially in the same plane as the rotary shaft 12.
A wheel shaft 24 that is an output shaft of the worm gear reduction device 22 is fixed on the center line of the worm wheel 23, and the wheel shaft 24 is disposed in a plane orthogonal to the rotating shaft 12 and is rotatably supported by the gear case 21. Has been.
The worm 13 and the worm wheel 23 are set so that the rotation of the rotary shaft 12 is sufficiently decelerated and transmitted to the wheel shaft 24.

As shown in FIGS. 4 and 5, in the wiper motor 1 according to the present embodiment, the rotation reduced by the worm gear reduction device 22 is converted into a swinging motion (reciprocating rotational motion of 360 degrees or less). A crank device 25 serving as a power transmission unit is connected and accommodated in the gear case 21.
That is, one end of a crank 26 is fixed to the wheel shaft 24 of the worm wheel 23 at a right angle, and one end of a connecting rod 27 is rotatably connected to the free end of the crank 26. A sector gear 28 is formed at the other end of the connecting rod 27, and an output gear 29 is engaged with the sector gear 28. The output gear 29 is fixed at right angles to a wiper shaft 31 as an output shaft, and the wiper shaft 31 is rotatably supported by the gear case 21 outside the worm wheel 23.
A swing plate 30 is mounted between the wiper shaft 31 and the rotating shaft of the sector gear 28, and the swing plate 30 is rotatably supported by the wiper shaft 31 and the rotating shaft of the sector gear 28, respectively. ing.
When the crank 26 revolves around the wheel shaft 24 by 180 degrees, the sector gear 28 moves forward by a predetermined angle, and when the crank 26 revolves the remaining 180 degrees, the sector gear 28 reverses and reverses by a predetermined angle. Therefore, the wiper shaft 31 as the final output shaft swings by a predetermined angle.

As shown in FIGS. 4 and 5, the gear case 21 is integrally formed by an aluminum die casting method using aluminum into a storage container shape having one end opened.
As shown in FIG. 3, a connector insertion port 32 is formed in a substantially T-shaped sideways at a portion corresponding to the rotating shaft 12 on the bottom wall (on the outer wall surface) of the gear case 21. The connector 33 shown in FIG. 6 is inserted into the mouth 32 and fixed.
The connector 33 is mounted with a holder portion 35 holding three contact plates 34 and a coupler portion 36 and is electrically connected.
The three contact plates 34 are inserted into the gear case 21 from the connector insertion port, and are in sliding contact with a relay plate (not shown) laid on the worm wheel 23.
The coupler part 36 is exposed to the outside of the gear case 21 and is connected to an assembled wire (not shown) of the wiper device.

As shown in FIGS. 1, 2, and 4, a portion (area) surrounding the wiper shaft 31 on the opening surface of the gear case 21 has a wiper shaft holding member (hereinafter referred to as a holding member) as an output shaft holding member. .) 40 is arranged so as to face opposite to the bottom surface of the gear case 21.
By disposing the wiper shaft 31 and the holding member 40 so as to face opposite to the bottom surface of the gear case 21, the coupler portion 36 can be disposed on the outer wall surface of the gear case 21, that is, on the vehicle interior side.
As a result, it is not necessary to direct the coupler portion 36 to the opposite side of the wiper shaft 31 and to provide an opening for connecting the coupler to the bracket as in the prior art. Since it can receive on the outer wall surface of the gear case 21 when connecting the wiring from a vehicle, the load to an assembled wire can be suppressed.
The holding member 40 is integrally formed using a resin having wear resistance and self-lubricating properties, and includes a covering portion 41 and a holding cylinder portion 42.
The covering portion 41 is formed in a substantially pentagonal flat plate shape (see FIGS. 2 and 5) and is formed so as to cover the wiper shaft 31, the output gear 29, the sector gear 28, and the connecting rod 27.
The holding cylinder part 42 is formed in a relatively thick and substantially cylindrical shape (see FIGS. 1, 2, and 4), and is disposed in a portion of the covering part 41 that faces the wiper shaft 31, and extends outward ( Projecting at a right angle to the bottom of the gear case 21. A bearing hole 43 is formed by the hollow portion of the holding cylinder portion 42.
As shown in FIG. 2, the holding member 40 is fastened to the gear case 21 by two bolts 44.

The wiper shaft 31 penetrates the bearing hole 43 of the holding member 40 and protrudes to the outside, and an intermediate portion is supported by the bearing hole 43 so as to be slidable in the circumferential direction.
The protruding end of the wiper shaft 31 is configured to support the base end of the wiper arm in a fixed manner, and a wiper blade for wiping the rear windshield glass is attached to the free end of the wiper arm. ing.

As shown in FIGS. 1, 2, 3, and 4, a bracket 50 is disposed adjacent to the holding member 40 in a portion (area) of the opening surface of the gear case 21 excluding the holding member 40. ing.
As shown in FIG. 2, the bracket 50 is fastened to the gear case 21 by two bolts 45.
As shown in FIG. 2, the bracket 50 is formed into a y-shaped flat plate shape that is substantially lateral in plan view by press working using an iron plate.
A cover 54 is formed at the center of the bracket 50, and the cover 54 covers the rotary shaft 12 and the worm wheel 23.
A rib 55 is bent at the edge of the bracket 50 so as to protrude to the opposite side of the gear case 21. The rib 55 can be simultaneously formed when the bracket 50 is pressed.
A first attachment portion 51, a second attachment portion 52, and a third attachment portion 53 are formed at three ends of the y-shape of the bracket 50, respectively.
The first attachment portion 51, the second attachment portion 52, and the third attachment portion 53 are provided with a notch portion 56. The notch portion 56 is made of a molding material having an elastic force of rubber or resin, and has a substantially cylindrical shape. A molded mount rubber 57 is fitted.
Although not shown, a cylindrical collar formed by rounding a metal plate is inserted into the insertion hole 58 of the mount rubber 57. Bolts are inserted into the collar insertion holes through washers.

The wiper motor 1 configured as described above is supplied from a wiper motor manufacturer to an automobile manufacturer.
In the automobile manufacturer, the wiper motor 1 is arranged near the rear windshield glass 61 (see FIG. 1) on the tailgate panel, and the bolts inserted into the three mounting portions 51, 52, 53 of the bracket 50. Is screwed into a nut pre-fixed to the panel.
By doing so, the rear wiper device can be installed on the rear windshield glass 61 with good layout performance.

  Incidentally, in the wiper motor 1 in which the three mounting portions 51, 52, 53 of the bracket 50 are provided with the mount rubber 57 and fastened with bolts and nuts, vibration generated by the operation of the electric motor 11 is transmitted to the panel side. Since the three mounting rubbers 57 prevent this phenomenon, noise generation can be suppressed.

  According to the embodiment, the following effects can be obtained.

(1) By holding the wiper shaft rotatably by the resin holding member, it is possible to omit the cutting of the gear case, so that the manufacturing cost of the wiper motor can be reduced.

(2) Since the wiper shaft is rotatably held by the resin holding member, a part of the iron bracket is replaced by the resin holding member, so that the weight of the iron bracket can be reduced. .

(3) By replacing a part of the iron bracket with a resin holding member, it is possible to leave the mounting portion of the iron bracket, so that it is not necessary to change the mounting layout to the automobile.

(4) Since the connector can be arranged on the vehicle interior side by arranging the connector on the bottom wall of the gear case, the shape and structure of the gear case and the connector and the wiring layout can be simplified.

(5) Mechanical strength, workability, heat dissipation performance, and the like can be maintained by integrally molding the gear case by aluminum die casting.

  Needless to say, the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the scope of the invention.

  The speed reducer that decelerates the rotation of the electric motor is not limited to the worm gear speed reducer, and a planetary gear speed reducer or the like may be used.

  The motion conversion device that is connected to the speed reduction device and converts the reduced rotation to the swing motion is not limited to the use of the crank device and may be omitted.

  In the above embodiment, the wiper motor for the rear wiper device has been described. However, the present invention is not limited to this, and can be applied to all wiper motors used in the front wiper device and the like.

It is a side view which shows the wiper motor which is one embodiment of this invention. It is the front view. FIG. It is sectional drawing which passes along a wiper shaft. It is a front view which shows the state which removed the bracket. The connector is shown, (a) is a side view, (b) is a front view, (c) is a side view of the coupler part, and (d) is a front view of the coupler part.

Explanation of symbols

1 ... wiper motor,
DESCRIPTION OF SYMBOLS 10 ... Motor part, 11 ... Electric motor, 12 ... Rotating shaft (armature shaft), 13 ... Worm,
DESCRIPTION OF SYMBOLS 20 ... Gear part, 21 ... Gear case, 22 ... Worm gear reduction device, 23 ... Worm wheel, 24 ... Wheel shaft, 25 ... Crank device, 26 ... Crank, 27 ... Connecting rod, 28 ... Sector gear, 29 ... Output gear, 30 ... oscillating plate, 31 ... wiper shaft,
32 ... Connector insertion port, 33 ... Connector, 34 ... Contact plate, 35 ... Holder part, 36 ... Coupler part,
40 ... Wiper shaft holding member (output shaft holding member), 41 ... Covering portion, 42 ... Holding cylinder portion, 43 ... Bearing hole, 44, 45 ... Bolt,
DESCRIPTION OF SYMBOLS 50 ... Bracket, 51 ... 1st attaching part, 52 ... 2nd attaching part, 53 ... 3rd attaching part, 54 ... Cover part, 55 ... Rib, 56 ... Notch part, 57 ... Mount rubber, 58 ... Insertion hole,
61: Rear windshield glass.

Claims (4)

A motor unit having an electric motor;
A power transmission unit housed in a bottomed gear case coupled to the motor unit and transmitting the rotation of the rotating shaft of the electric motor to an output shaft;
An output shaft holding member made of resin that covers the opening of the gear case and rotatably supports the output shaft;
A bracket that is adjacent to the output shaft holding member and covers an opening of the gear case;
Wiper motor with   The wiper motor according to claim 1, wherein a connector is disposed on a bottom wall of the gear case.   The wiper motor according to claim 1 or 2, wherein the gear case is made of aluminum die casting.   The wiper motor according to claim 1, wherein the bracket is made of iron.

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