CN111409593B

CN111409593B - Automatic reset control device for wiper motor

Info

Publication number: CN111409593B
Application number: CN202010323999.9A
Authority: CN
Inventors: 李万军
Original assignee: Anhui Shenghuabo Auto Electric Co ltd
Current assignee: Anhui Shenghuabo Auto Electric Co ltd
Priority date: 2020-04-22
Filing date: 2020-04-22
Publication date: 2023-06-02
Anticipated expiration: 2040-04-22
Also published as: CN111409593A

Abstract

The invention discloses an automatic reset control device of a wiper motor, which comprises a reduction box body, a reduction box cover plate, a gear and a return plate, wherein the reduction box cover plate covers the reduction box body; a first friction surface is arranged on the inner diameter of the return disc; a second friction surface is arranged on the surface of the return plate opposite to the gear; under the action of downward pressure applied by the plurality of elastic return reeds to the return plate, a second friction surface on the return plate is in friction contact with a first friction surface on the return plate, so that circumferential rotation (around a gear axis) of the return plate is guaranteed to have friction force, the return plate cannot rotate in a free state, and the return plate can only rotate under a given rotation moment. The invention has simpler structure and lower cost.

Description

Automatic reset control device for wiper motor

Technical Field

The invention relates to the technical field of wiper motors, in particular to an automatic reset control device of a wiper motor.

Background

The automobile front windshield wiper has the functions that the transmission mechanism drives the two wiper arm and the wiper blade to wipe dirt and dust on the windshield glass, and after the wiper blade is wiped for a plurality of times, the reset switch is shifted to connect the positive electrode of the power supply to the reset position. If the internal reset is not short-circuited, i.e. is not in the reset position, the current passes through a diode in the vehicle body controller to the low-speed end, so that the motor continues to turn to the reset position, and the wiper arm and the wiper blade are not caused to stop at any position of the windshield. When the motor is turned to the reset position, i.e. the positive low-speed end is short-circuited, i.e. the so-called "generator braking effect", the motor stops, and the wiper arm and the wiper blade return to the original park position. This is a general principle of an automatic reset system for an automobile wiper blade.

Such asFIGS. 1 to 3The existing motor is shown to be combined by the motor cover plate subassembly 3 and the worm gear subassembly 1 to finish the functions of running and resetting the motor. According to the motor resetting working principle, two resetting reeds 3-1 and 3-2 are arranged on the motor cover plate subassembly 3 and are arranged on the same radial line of the axis of the worm wheel in parallel and contacted with different positions of the worm wheel metal resetting plate 1-2, so that the aim of controlling the motor to reset is fulfilled.

The worm wheel metal reset plate is fixedly connected with a gear shaft in the gear, and the gear synchronously drives the worm wheel metal reset plate to rotate when rotating, but when the scraping arm approaches to a return position (the scraping arm is at an initial installation position) in an automatic return process under the condition of high resistance such as snow resistance of a front windshield, the scraping arm can not return to the initial position, so that a motor travel switch can easily form repeated short-time contact and instant on-off to generate ablative plastic gears, and the motor can not work.

Therefore, one can independently manufacture the worm wheel metal reset plate into a reset plate, the inner diameter of the reset plate is in clearance fit with the outer diameter of the gear shaft, a salient point or an annular groove with the central angle smaller than 360 degrees is arranged on the outer diameter of the gear shaft, and meanwhile, an annular groove with the central angle smaller than 360 degrees is arranged on the inner diameter of the reset plate or a salient point is arranged on the inner diameter of the reset plate, and the salient point is embedded into the annular groove with the central angle smaller than 360 degrees. In the automatic return process, the gear shaft is matched with the wall of the annular groove with the central angle smaller than 360 degrees through the salient points to drive the return plate to return, if the resistance is met, such as when the front windshield has snow resistance, the scraping arm approaches to the return position (the scraping arm is at the initial installation position) in the automatic return process, the scraping arm cannot return to the initial position, the gear can not drive the return plate to rotate reversely when the reaction force rotates, and thus the motor travel switch can not form repeated transient contact instant on-off to heat and burn out the return plate and the gear. However, in such a structure, a complicated mechanism is required to restrict the return plate from being rotatable in a free state, and only at a given rotational moment, the return plate can be rotated, resulting in an increase in cost.

Disclosure of Invention

The invention aims to solve the technical problems of the wiper motor and provides an automatic reset control device of the wiper motor, which ensures that the reset plate rotates circumferentially (around the axis of a gear) with friction force, is not rotatable in a free state, can rotate only under a given rotation moment, and simultaneously has simple structure and reduced cost

The technical problems to be solved by the invention can be realized by the following technical scheme:

the automatic reset control device for the wiper motor comprises a reduction box body, a reduction box cover plate, a gear and a return plate, wherein the reduction box cover plate covers the reduction box body, the gear is rotatably arranged in the reduction box body, the return plate is sleeved at the upper end of a gear shaft of the gear, the inner diameter of the return plate is in clearance fit with the outer diameter of the gear shaft, and the return plate can float on the upper axis of the gear shaft; the outer diameter of the gear shaft is provided with a salient point or an annular groove with a central angle smaller than 360 degrees, and meanwhile, the inner diameter of the return plate is provided with an annular groove with a central angle smaller than 360 degrees or the inner diameter of the return plate is provided with a salient point, and the salient point is embedded into the annular groove with the central angle smaller than 360 degrees; the metal reset plate is arranged on the reset plate, and a plurality of reset elastic reeds are arranged on the cover plate of the reduction gearbox, and the reduction gearbox is characterized by further comprising a reset disc, wherein the outer diameter of the reset disc is fastened in the reduction gearbox; a first friction surface is arranged on the inner diameter of the return disc; a second friction surface is arranged on the surface of the return plate opposite to the gear; under the action of downward pressure applied by the plurality of elastic return reeds to the return plate, a second friction surface on the return plate is in friction contact with a first friction surface on the return plate, so that circumferential rotation (around a gear axis) of the return plate is guaranteed to have friction force, the return plate cannot rotate in a free state, and the return plate can only rotate under a given rotation moment.

In a preferred embodiment of the invention, both the first friction surface and the second friction surface are flat or beveled.

In a preferred embodiment of the invention, a concave ring groove is arranged in the reduction box body, and the outer diameter of the return disc is assembled in the concave ring groove and is tightly matched with the concave ring groove.

In a preferred embodiment of the invention, the bottom groove wall of the concave ring groove defines the axial lower limit position of the return disc.

In a preferred embodiment of the invention, a stepped surface is provided at the location of the gear shaft for receiving the return plate, the stepped surface defining the axial lower limit position of the return plate.

Due to the adoption of the technical scheme, the invention ensures that the return plate circumferentially rotates (around the gear axis) with friction, the free state can not rotate, the return plate can only rotate under a given rotation moment, and the invention has simpler structure and lower cost.

Drawings

FIG. 1Is a schematic structural diagram of the prior motor worm gear sub-assembly.

FIG. 2Is a schematic diagram of the prior motor worm wheel reset plate structure.

FIG. 3Is a schematic diagram of the structure of the existing motor cover plate sub-assembly.

Fig. 4 is a schematic structural view of the automatic reset control device of the wiper motor of the present invention.

Fig. 5 is an enlarged schematic view at C of fig. 4.

Fig. 6 is a schematic structural view of the return plate of the present invention.

Fig. 7 is a schematic view of the return disc structure of the present invention.

Fig. 8 is a schematic view of the structure of the gear and the gear shaft of the present invention.

Detailed Description

The invention is further described below with reference to the drawings and detailed description.

Referring to fig. 4 to 8, there is shown a wiper motor automatic reset control apparatus including a reduction gearbox 10, a reduction gearbox cover plate 20 covering the reduction gearbox 10, a gear 30 rotatably disposed in the reduction gearbox 10, and a reset plate 40 sleeved on an upper end of a gear shaft 31 of the gear 30.

The inner diameter D1 of the return plate 40 is in clearance fit with the outer diameter D3 of the gear shaft 31, and the return plate 40 can axially float on the gear shaft 31; the mode of the gear shaft 31 driving the return plate 40 to rotate is not different from the prior art, namely, a salient point 31a is arranged on the outer diameter D3 of the gear shaft 31 or a circular groove with a central angle smaller than 360 degrees is arranged on the outer diameter D3 of the gear shaft 31 (in the specific embodiment, the salient point 31a is arranged on the inner diameter D1 of the return plate 40, a circular groove 41 with a central angle smaller than 360 degrees is arranged on the inner diameter D1 of the return plate 40) at the same time, the salient point 31a is embedded into the circular groove 41 with a central angle smaller than 360 degrees, so that in the automatic return process, the gear shaft 31 drives the return plate to return through the cooperation of the salient point 31a and the wall of the circular groove 41 with a central angle smaller than 360 degrees, and if the scraping arm approaches to a return position (in the initial installation position) in the automatic return process under the condition of collision resistance such as the front windshield, the scraping arm can not return to the initial installation position because the scraping arm can not return to the initial position, and when the gear 30 rotates under the counter acting force, the salient point 31a leaves the wall with a central angle smaller than 360 degrees, the circular groove 41 is embedded into the circular groove 41, thus the return plate 40 is not driven to be damaged by the moment, and the return stroke of the return plate 40 is not repeatedly and the return stroke of the gear is not generated.

The gear shaft 31 is provided with a step surface 31b at a position for sleeving the outer diameter 41 of the return plate 40, and the step surface 31b limits the axial lower limit position of the return plate 40. By limiting the stepped surface 31b in this way, the protruding point 31a can be inserted into the intermediate position of the ring groove 41 having the central angle smaller than 360 ° and can not be in frictional contact with the upper and lower groove surfaces of the ring groove 41.

A metal reset plate 42 is arranged on the reset plate 40, and a plurality of reset elastic reeds 21 are arranged on the cover plate 20 of the reduction gearbox. The reset spring reed 21 contacts with different positions of the metal reset plate 42 on one hand so as to achieve the purpose of controlling the reset of the motor; on the other hand, a downward pressure is also applied to the return plate 40.

The invention aims to solve the problem of ensuring that the return plate 40 rotates circumferentially (around the gear axis) with friction by adopting a simpler structure, the return plate 40 can only rotate under a given rotation moment, and the invention has the advantages of simpler structure and lower cost. Based on the inventive thought, the technical scheme adopted by the invention is as follows:

the speed reduction box body 10 further comprises a return disc 50, wherein the outer diameter 51 of the return disc 50 is fastened in the speed reduction box body 10, and one specific method is as follows: a concave ring groove 11 is provided in the reduction gearbox 10, an outer diameter 51 of the return disc 50 is fitted in the concave ring groove 11 and is tightly fitted with the concave ring groove 11, and a bottom groove wall 11a of the concave ring groove 11 defines an axial lower limit position of the return disc 50.

A first friction surface 52 is provided on the inner diameter D2 of the return disc 50, the first friction surface 52 being planar or beveled. A second friction surface 43a is arranged on the surface 43 of the return plate 40 facing the gear 30, and the second friction surface 43a is also a flat surface or an inclined surface adapted to the first friction surface 52.

Under the downward pressure applied by the plurality of return spring reeds 21 to the return plate 40, the second friction surface 43a on the return plate 40 is in friction contact with the first friction surface 52 on the return plate 50, so that circumferential rotation (around the gear axis) of the return plate 40 is ensured, the return plate 40 cannot rotate in a free state, and only under a given rotation moment, the return plate 40 can rotate.

Claims

1. The automatic reset control device for the wiper motor comprises a reduction box body, a reduction box cover plate, a gear and a return plate, wherein the reduction box cover plate covers the reduction box body, the gear is rotatably arranged in the reduction box body, the return plate is sleeved at the upper end of a gear shaft of the gear, the inner diameter of the return plate is in clearance fit with the outer diameter of the gear shaft, and the return plate can float on the upper axis of the gear shaft; the outer diameter of the gear shaft is provided with a salient point or an annular groove with a central angle smaller than 360 degrees, and meanwhile, the inner diameter of the return plate is provided with an annular groove with a central angle smaller than 360 degrees or the inner diameter of the return plate is provided with a salient point, and the salient point is embedded into the annular groove with the central angle smaller than 360 degrees; the metal reset plate is arranged on the reset plate, and a plurality of reset elastic reeds are arranged on the cover plate of the reduction gearbox, and the reduction gearbox is characterized by further comprising a reset disc, wherein the outer diameter of the reset disc is fastened in the reduction gearbox; a first friction surface is arranged on the inner diameter of the return disc; a second friction surface is arranged on the surface of the return plate opposite to the gear; under the action of downward pressure applied by the plurality of elastic return reeds to the return plate, a second friction surface on the return plate is in friction contact with a first friction surface on the return plate, so that circumferential rotation (around a gear axis) of the return plate is guaranteed to have friction force, the return plate cannot rotate in a free state, and the return plate can only rotate under a given rotation moment.

2. The automatic reset control device for a wiper motor according to claim 1, wherein the first friction surface and the second friction surface are both flat surfaces or inclined surfaces.

3. The automatic reset control device for a wiper motor according to claim 1, wherein a concave ring groove is provided in the reduction gearbox, and the outer diameter of the reset disc is fitted in the concave ring groove and is tightly fitted with the concave ring groove.

4. A wiper motor automatic reset control apparatus according to claim 3, wherein the bottom groove wall of the concave ring groove defines the axial lower limit position of the return disc.

5. The automatic reset control device for a wiper motor according to claim 1, wherein a stepped surface is provided at a portion of the gear shaft for housing the return plate, the stepped surface defining a lower limit position in an axial direction of the return plate.