JPH0226113Y2 - - Google Patents

Description

[Detailed description of the invention] The present invention applies to various parts of automobiles, scooters, etc., such as retractable headlamp drive parts, rearview mirror wiper drive parts, windshield wiper drive parts,
The present invention relates to a contact structure of a motor drive device installed in a headlamp wiper drive unit, a rear window wiper drive unit, etc.

This type of motor drive device generally includes a reduction gear mechanism that is rotationally driven by a motor, a mechanism that converts rotational motion into reciprocating motion, a printed circuit board that constitutes a control circuit for the motor, and starting and stopping of the motor. A contact mechanism that controls A structure is used in which contact terminals are fixedly supported by a housing and these contact terminals are soldered to a printed circuit board via a harness.

FIG. 1 is a plan view of a wiper drive device as an example of a motor drive device, with the lid of the housing 1 removed.

The rotation of the motor 2 is transmitted to a final reduction gear 6 via a worm gear 3, a worm wheel 4, and a secondary gear 5. This final reduction gear 6 reciprocates a rack 8 via an eccentric cam 7, and a pinion 9.
The wiper shaft 10 fixed to is rotated back and forth.

Reference numeral 11 denotes a printed circuit board constituting a control circuit for the motor, on which electrical components such as a relay 12 and a diode 13 are mounted.

A contact mechanism for controlling the motor 11 to stop at a predetermined position is provided as described below.

The contact mechanism is hidden in Figure 1. 14 represented by a hidden line is a contact terminal in the form of a leaf spring.
A contact plate that slides into electrical contact with the contact terminal 14 and is electrically connected is fixed to the back surface of the final reduction gear 6.

FIG. 2 is a back view of the final reduction gear 6, in which a plate 15 (drawn with hatching for ease of reading) on which a conductive contact pattern is formed is fixed to the plate 15. The tip of the leaf spring-shaped contact terminal 14 is in sliding contact.

In the contact mechanism for driving the motor as described above, it is quite difficult to incorporate a plurality of contact terminals 14 into the narrow space between the final reduction gear and the housing.
Moreover, it is difficult to reduce the size and weight of the entire device by reducing the diameter of the plate 15.

As a mounting member for the above contact terminal 14,
Generally, as shown in Fig. 3, a structure is used in which machine screws 18 are used and soldered to a harness 20 via a washer-like terminal plate 19 to provide electrical continuity to the printed circuit board 11, but (i) the number of component parts is large. Therefore, the number of assembly steps is large, and process management is not easy. (ii) There is a limit to reducing the width of the contact terminal.
(iii) Due to the complicated structure, it is impossible to make the device smaller and lighter, resulting in higher costs.

The present invention was created in view of the above circumstances, and it is possible to significantly reduce the width of the leaf spring-shaped contact terminal and make it linear, and to create a contact structure that is easy to assemble and easy to control the process during production. The purpose is to provide. Due to the reduction in the width of the contact terminal,
It is possible to increase the number of contact terminals installed, shorten the installation pitch of contact terminals, and downsize contact plates and other parts. As a result, it is naturally expected that the entire device will be smaller, lighter, and cost lower. .

In order to achieve the above object, the contact structure of the motor drive device of the present invention comprises a reduction gear mechanism that is rotationally driven by the motor, a mechanism that converts rotational motion into reciprocating motion, and a motor control circuit. In a motor drive device in which a printed circuit board and a contact mechanism for controlling the start and stop of the motor are housed in a housing, a plate on which a contact pattern is formed is fixed to the back surface of the final reduction gear, and a plate separate from the housing is used. A contact terminal supporting block is provided on the body, and a plurality of contact terminals having spring elasticity are fitted into grooves formed in this block to form a subassembly of the contact terminal, and the above block is positioned through a positioning means. The contact terminal is brought into contact with the housing, and the printed circuit board is used to press the contact terminal against the block, and the block is pressed against the housing to fix the block to the housing, and the elastic restoring force of the contact terminal causes one end of the contact terminal to be pressed against the block. The contact terminal is characterized in that it is brought into contact with and electrically connected to the plate on which the contact pattern is formed, and the other end of the contact terminal is brought into contact with and electrically connected to the conductive portion of the substrate.

Next, one embodiment of the present invention will be described with reference to FIGS. 4 to 9. In FIG. 4, 1 is a housing, 15 is a plate fixed to the back surface of the final reduction gear 6, 11 is a printed circuit board, and 11a is a conductive portion of the printed circuit board.

Reference numeral 16 designates a spring rod-shaped contact terminal, which corresponds to the contact terminal 14 in the conventional device, but its width has been reduced compared to the conventional device, and the shape is closer to a wire spring than to a plate spring shape. be.

The above contact terminal 16 has one end 16a
The other end 16b is formed into a shape suitable for contact and conduction with the conductive portion 11a of the printed circuit board 11.

A block 17 supports the contact terminal 16, and grooves 17a and 17b are formed into which the contact terminal 16 is fitted. In order to position this block 17 with respect to the housing 1, a pin 1a is attached to the bottom of the housing 1.
A hole 17c is provided in the block 17 to fit the two parts together.

FIG. 5 is an external view of the block 17 in which the grooves 17a and 17b are formed as described above, as viewed in the direction of arrow A. FIG. 6 is an external view of the block 17 into which the contact terminal 16 is fitted, as seen in the direction of arrow B.

FIG. 7 is a partial sectional view similarly viewed in the direction of arrow C, in which the aforementioned pin 1a and hole 17c appear in the cross section.

FIG. 8 is a cutaway perspective view of the block 17, and FIG. 9 shows a contact terminal 16 fitted into one of the plurality of grooves 17a, 17b provided in the block 17. It is a perspective view depicting the combined parts.

Four contact terminals 16 are fitted into this block 17 as shown in FIGS. 6 and 7 to form a subassembly, and this subassembly is connected to a positioning means (in this example, a pin is used as shown in FIG. 4). 1a and hole 17c), the block 17 is pressed against the printed circuit board 11, and the printed circuit board 11 is fixed to the housing 1 by fixing means (not shown).
Fixed to. As a result, the block 17 is positioned and fixed relative to the housing 1. At the same time, the contact terminal 16 is pressed toward the block 17 and elastically deformed, and due to its elastic restoring force, one end 16a of the contact terminal is pressed against the plate 15 on which the contact pattern is formed, and the other end 16b is pressed against the conductive part of the printed circuit board 11. 11a, and are brought into contact with each other.

In this embodiment, the subassemblies shown in FIGS. 6 and 7 can be assembled in advance and assembled into the housing 1, so that process management and materials management in the assembly line can be carried out. It is easy to use and convenient for managing spare parts. When the block 17 and the contact terminal 16 are handled as a subassembly in this way, in order to prevent the fitted contact terminal 16 from slipping out of the grooves 17a and 17b, in this embodiment, a stopper protrusion 17d is provided on the side surface of the groove 17b. It is provided.

In addition, as an embodiment different from the above, the block 17 is made of thermoplastic synthetic resin, the protrusion 17d is omitted, and after the contact terminal 16 is fitted, a soldering iron is applied to the side surface of the groove 17b to connect the contact. The terminal 16 may be lightly caulked.

The contact structure configured as described above does not require any parts such as machine screws or washers, so there are fewer components, and reliable conduction can be obtained without soldering the contact terminals, so the number of assembly steps is reduced. It's over.

Furthermore, since there is no need to provide a screw hole for mounting, the contact terminal 16 can be configured as a thin spring rod in the shape of a wire spring, and the installation pitch dimension P can be reduced. Therefore, by reducing the diameters of the plate 15 and the final reduction gear 6, the entire device can be made smaller and lighter.

As described in detail above, according to the present invention, the width of the contact terminal and its installation pitch can be significantly reduced, and furthermore, it can be easily and quickly assembled in a narrow space. It is technically easier to make the entire device smaller and lighter. Furthermore, the number of man-hours required for assembly is small and process control is easy, which greatly contributes to cost reduction.

[Brief explanation of drawings]

FIG. 1 is a plan view of the motor drive device, FIG. 2 is a back view of an example of a contact portion of the motor drive device, and FIG. 3 is a side sectional view of the same. 4 to 9 show one embodiment of the present invention, FIG. 4 is a side sectional view,
Fig. 5 is an external view of the block as seen in the direction of arrow A, Fig. 6 is an external view of the subassembly of the block and contact terminal as seen in the direction of arrow B, and Fig. 7 is an external view of the subassembly of the block and contact terminal as seen in the direction of arrow C. FIG. FIG. 8 is a cutaway perspective view of the block, and FIG. 9 is a cutaway perspective view of the block with contact terminals fitted therein. DESCRIPTION OF SYMBOLS 1... Housing, 1a... Pin as positioning means, 2... Motor, 3... Worm gear, 4... Worm foil, 5... Secondary gear, 6... Final reduction gear, 7... Eccentric cam, 8...
... rack, 9 ... pinion, 10 ... wiper shaft, 11 ... printed circuit board, 11a ... conduction part,
12... Relay, 13... Diode, 14...
Contact terminal, 15... Plate with contact pattern formed, 16... Contact terminal, 17...
Blocks, 17a, 17b...grooves, 17c...holes as positioning means, 17d...protrusions for stoppers.

Claims (1)

[Scope of utility model registration request] A reduction gear mechanism that is rotationally driven by the motor, a mechanism that converts rotational motion into reciprocating motion, a printed circuit board that constitutes the motor control circuit, and a contact mechanism that controls starting and stopping of the motor are housed in the housing. In the motor drive device that is housed, a plate 15 on which a contact pattern is formed is fixed to the back surface of the final reduction gear 6, and a block 17 for supporting a contact terminal is provided separately from the housing, and a contact terminal support block 17 is formed on this block. A plurality of contact terminals 16 having spring elasticity are fitted into the grooves to constitute a contact terminal subassembly, and the block 17 is brought into contact with the housing 1 via a positioning means, and the printed circuit board 1
1, the contact terminal 16 is pressed against the block 17, and the block 17 is pushed into the housing 1.
The elastic restoring force of the contact terminal 16 brings one end 16a of the contact terminal into contact with the plate 15 on which the contact pattern is formed, making it conductive. A contact structure for a motor drive device, characterized in that the other end 16b is brought into contact with a conductive portion 11a of a printed circuit board 11 for conduction.