JPS6114920Y2 - - Google Patents

Description

[Detailed description of the invention] This invention relates to an automatic stop device for vehicle wipers, and in particular, when the switch of the drive motor of the wiper that wipes the front windshield of a car is opened, the wiper blade is stopped. The present invention relates to an improvement in an automatic stop device for a vehicle wiper that automatically stops the wiper at a position at the lower edge of a window frame that does not obstruct the driver's view.

Conventionally, as this type of automatic stop device, one shown in FIG. 1 has been proposed.

That is, M is the electric motor, E is the power source, S is the switch, 1 is the worm on the rotating shaft side of the electric motor, 2 is the worm gear, 3 is the gear shaft, and 4 and 5 are conductive plates provided on the end face of the gear in an electrically insulating manner. , 6, 7, and 8 are conductive brushes supported on the gear housing side, and the gear shaft 3 is an output shaft that swings the wiper blade via a crank mechanism, and the switch S is connected to the wiper drive contact a. Even when switching to stop contact b, power continues to be supplied to the motor while the brushes 6 and 7 are connected via the conductive plate 4.
When the brushes 7 and 8 are connected by the conductive plate 5, the power supply to the motor is cut off, and at the same time a short circuit is formed between the brushes of the motor, electric control is activated, and the motor is stopped and the output is gear 2
The wiper blade, whose operation is linked via a crank mechanism, is automatically stopped at a fixed position (lower edge position of the window frame) regulated by the rotation angle of the gear 2.

The automatic stop device for vehicle wipers with the above configuration does not pose any particular problems in terms of the wiper automatic stop function, but the structure of the electrically conductive part consisting of the conductive plate member and the brush is complicated, and the reliability is poor. There are some shortcomings, and there are still some points to be improved, such as the need for a separate means for absorbing and removing rattling in the thrust direction of the output shaft 3.

In addition, this type of wiper automatic stop device is also disclosed in Japanese Utility Model Application Publication No. 55-131855 and Japanese Patent Application Publication No. 54-99234, but it includes a means for absorbing looseness in the thrust direction of the output shaft, and a ground conductor. No improvements have been made to the strategy.

This invention simplifies the electrically conductive part and improves its reliability in the configuration of the above-mentioned automatic stop device for vehicle wipers, and also provides a special means to prevent rattling in the thrust direction of the output shaft. The object of the present invention is to provide an automatic stop device for a vehicle wiper that can absorb and remove the liquid without causing any damage.

Hereinafter, this invention will be explained in detail based on the drawings showing an example of its implementation.

In FIGS. 2 to 5, members that are the same as or similar to those constituting the conventional apparatus shown in FIG. 1 are given the same reference numerals.

In other words, 2 is a worm gear, 3 is a gear support shaft, 9 is a metal gear housing, and 10 is a metal cover plate. On the upper end surface of the worm gear 2, a metal conductive plate 11 is connected to the electrically conductive plate 11. Fixed insulated. In that case, if the gear 2 is made of synthetic resin, there is no need for means for insulating the conductive plate 11 from the gear.

The conductive plate 11 has two conductive brushes 1 which are cut up to a height that can come into contact with the inner surface of the housing 10 and whose tips are curved in an arc shape.
1a and 11b are provided.

On the other hand, an electrically insulating plate 12 is fitted into the cover plate 10 in a plate portion extending in the radial direction from the center portion thereof.
A first conductive member 13 is provided penetratingly in the insulating plate 12 at a portion facing the gear support shaft 3, and a second conductive member 14 is provided penetratingly at a portion eccentric from the support shaft 3. , the first conductive brush 1
1a is positioned such that its tip curved portion presses the end face of the gear support shaft 3 and is always in contact with the first conductive member 13 on the cover plate 10 side, and the second conductive brush 11b is configured to control the specific rotation of the output gear 2. It is positioned so that it contacts the second conductive member 14 on the cover plate side at the corner position, and contacts the cover plate 10 at other rotational angle parts. The cover plate 10 serves as a third conductive member for grounding.

The first conductive member 13 and the second conductive member 14
The third conductive member is connected to the start/stop circuit of the electric motor M by the cover plate 10, as shown in FIG. That is, the first conductive member 13 is connected to the wiper stop contact b of the switch S, the second conductive member 14 is connected to the positive electrode side of the power source E, and the third conductive member, the cover plate 10, is grounded.

In the wiper automatic stop device configured as described above, the switch S is connected to the wiper drive contact a.
When switching from to the stop contact b, while the second conductive brush 11B of the conductive plate 11 is in contact with the cover plate 10, the first conductive brush 11a - second conductive brush 11b - cover plate 10 - power source E is connected. The circuit continues to supply power to the motor, and the second conductive brush 11
When b is connected to the second conductive member 14, the power supply to the motor is cut off, and at the same time a short circuit is formed between the brushes of the motor, electric braking is activated, and the motor is stopped and the output gear 2 is turned to a crank position. The wiper blades, which are linked in operation through the mechanism, are automatically stopped at a predetermined position (lower edge position of the window frame) regulated by the rotation angle of the gear 2.

Therefore, as described above, the conductive plate 11 having the conductive brushes 11a and 11b is disposed on the gear 2,
When the second conductive brush 11b is configured to be in sliding contact with the cover plate 10, the cover plate 10 can be used together with the housing 9 as a conductive path for grounding. The configuration is significantly simplified compared to the conventional one described above.

Furthermore, the tip portion of the first conductive brush 11a on the conductive plate 11 is curved into the shape of a disc spring, and is pressed against the end surface of the gear support shaft 3 while maintaining contact with the first conductive member 13 on the cover plate side. According to the configuration in which the first conductive brush 11 is engaged in an elastic state, the first conductive brush 11
Since the backlash of the gear support shaft in the thrust direction is absorbed by the elastic action of the distal end disc spring portion of a, the installation of a backlash absorbing means can be omitted. Further, in that case, the elasticity of the disk spring portion can be adjusted by the degree of curvature thereof and the pressing force of the cover plate that is pressed into contact with the first conductive member 13, so that an optimum elastic force can be easily obtained.

As described above, according to this invention, the output gear of the reduction gear mechanism linked to the wiper drive motor is disposed in the housing chamber formed by the housing and the cover plate while being supported by the spindle. ,
On the side surface of the output gear facing the cover plate, a groove is formed by cutting a metal plate to a height that can contact the inner surface of the cover plate, and curving the tip of the cut in an arc shape. A conductive plate having a first conductive brush and a second conductive brush is fixed, and a first conductive member is attached to the cover plate at a portion facing the spindle of the output gear.
In addition, second conductive members are arranged in an electrically insulated manner at positions that are eccentric by the support shaft, and the first conductive brush is placed on the cover plate side with its curved tip pressing against the end surface of the support shaft of the output gear. The second conductive brush is positioned so as to be in constant contact with the first conductive member, and the second conductive brush is in contact with the second conductive member on the lid plate side at a specific rotation angle position of the output gear, and at other rotation angle portions, the lid is grounded. Since the first conductive member, the second conductive member, and the cover plate are positioned so as to be in contact with the plate and are used as terminals of the start/stop circuit of the wiper drive motor, the above-mentioned conventional wiper automatic stop device Compared to the above, it is possible to obtain an automatic stop device for a vehicle wiper in which the conduction path portion forming the automatic stop circuit can be greatly simplified and the rattling of the output gear support shaft can be absorbed by a simple means.

[Brief explanation of the drawing]

Fig. 1 is an explanatory diagram of the configuration of the main parts of a conventional automatic stop device for vehicle wipers, Fig. 2 is a vertical sectional view of the main parts of an automatic stop device showing an embodiment of this invention, and Fig. 3 is a cover of the gear housing. The back plate of the plate, FIG. 4 is a perspective view of the conductive plate for the brush, and FIG. 5 is a configuration explanatory diagram of the main parts of the automatic stop device. M...Electric motor, E...Power supply, S...Switch, 1...Woom, 2...Worm gear, 3...Gear shaft, 4, 5...
Conductive plate, 6, 7, 8 conductive brush, 9... Gear housing, 10... Lid plate, 11... Conductive plate, 11a, 11
b... Conductive brush, 12... Insulating plate, 13... First conductive member, 14... Second conductive member.

Claims (1)

[Scope of utility model registration request] An output gear 2 of the reduction gear of the wiper drive motor is disposed in a housing chamber formed by the housing 9 and the cover plate 10 in a state where it is supported by a spindle, and the output gear 2 is located on the side facing the cover plate 10. A first conductive brush 11a and a second conductive brush are formed by cutting a metal plate to a height that can contact the inner surface of the lid plate 10, and curving the tip of the cut into an arc. 11b is fixed, and the cover plate 10 has a first conductive member 13 at a portion facing the spindle of the output gear 2, and a second conductive member 14 at a portion eccentric from the spindle. Each of the first conductive brushes 11a is electrically insulated, and the first conductive brush 11a is in constant contact with the first conductive member 13 on the cover plate 10 side, with its curved tip elastically pressing the end face of the spindle of the output gear 2. It is positioned as
The second conductive brush 11b contacts the second conductive member 14 on the cover plate 10 side at a specific rotation angle position of the output gear 2, and the cover plate 1 is grounded at other rotation angle positions.
0, and the first conductive member, the second conductive member, and the cover plate 10 are used as terminals of a start/stop circuit for a wiper drive motor. .