JPS5926346A - Gear support mechanism in motor unit case - Google Patents

Abstract

PURPOSE:To keep the proper engagement of a rack and a pinion through simple constitution and assembly, by providing a rack holder with tongues as plate springs and using the flexural elasticity of the tongues to urge the rack to te pinion. CONSTITUTION:A receiving gear 4 is rotated by a motor 2 through a speed reduction gear mechanism 3 so that a rack 7 provided on a cam follower 6 is moved back and forth by a crank means comprising the cam follower and an eccentric cam 5 attached to the receiving gear. A pinion 9 fitted on a wiper shaft 8 is turned back and forth by the rack 7. A rack holder 10 is provided with a through hole 10a in which the wiper shaft 8 is movably fitted. A part of the rack holder 10 is bent as U at 10b to hold the rack 7 around it. Notches are provided at both the ends of the bottom of the bent portion 10b so that tongues 10d are formed as plate springs. The rack 4 is urged to the pinion 9 by the flexural elasticity of the tongues 10d.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a gear holding mechanism within a motor unit case.

Wipers used for automobile windows, mirrors, headlamps, etc. generally have a structure in which a wiper shaft supporting a wiper blade is rotated back and forth. Therefore, the wiper drive device uses a gear mechanism to reduce the rotational output of the motor. A structure is often used in which a rank is reciprocated via a crank means, a pinion fitted on a wiper shaft is engaged with a rack, and the pinion is driven to reciprocate and rotate.

A rack holder is provided to guide the above-mentioned rack in its proper meshing state with the binoculars, but the tooth surfaces of the pinion and rack, or the sliding contact surface between the rack and the rack holder, When it wears out, the bank rack increases, and the wiper shaft is unable to rotate smoothly back and forth, resulting in a 7-stroke cycle. Further, since one end of the rack is connected to and driven by a crank means, the rack does not perform pure linear parallel reciprocating motion.
That is, the free end of the rack makes a linear reciprocating motion, and the other end of the rack makes a circular motion driven by the crank means.

Therefore, the rack as a whole performs a so-called connecting rod motion, which is a combination of linear reciprocating motion and rotational reciprocating motion. For this reason, the rack holder not only guides the rank linearly, but also has to allow for its reciprocating rotational movement, requiring a complex 9 structure. There is a risk that uneven wear may occur.

The present invention has been made in view of the above-mentioned circumstances ((), and is designed to guide the reciprocating movement of the rank while smoothly adapting to the rotation of the rank without causing excessive vano crush between the rank and the pinion. It is an object of the present invention to provide a gear holding mechanism in a motor unit case, which has a knock guide means with a simple structure and easy assembly, which can maintain a normal meshing relationship with a pinion.

In order to achieve the above object, the gear holding mechanism of the present invention includes:
A gear holder AN K # that engages a rank with a binion fitted on the wiper shaft, and causes the rank to reciprocate by means of a crank means C to reciprocate and drive the wiper shaft.
6, a bearing hole for fitting the wiper shaft is formed in a plate-like member having spring elasticity, and a U-shaped portion for holding the rank is formed to constitute a rank holder, and the rank holder is configured to hold a rank. It is characterized in that a pie-shaped tongue piece 2 is formed at a location opposite to the back side of the plate, and the elasticity of this tongue piece is intended to bias the rank toward the pinion.

Next, one embodiment of the present invention will be described with reference to the accompanying drawings.

FIG. 1 shows an example of the gear holding mechanism of the present invention with the lid of the motor unit 2-1 removed. Reference numeral 2 denotes a driving motor, the rotational driving force of which is reduced by a reduction gear mechanism 3 to rotate the final stage entertainment wheel 4. The center cam 5 attached to this receiving gear 4 and the cam follower 6 constitute a crank means, which reciprocates a rank 7 integrally molded with the cam follower 6, and is fitted onto the wiper shaft 8 by this rack 7. The present invention, which reciprocates and rotates the pinion 9, is based on elasticity. A rack holder is constructed by molding a J-shaped part that holds a rank with a plate-like member having the above-mentioned structure. An enlarged detailed view of the area around rank 7 is shown in FIG. 1o shown in this figure is a rank holder configured to hold the rack 7 and guide the reciprocating movement of the rack while maintaining the meshing relationship between the rank and the binion 9.

The rank holder 10 of this embodiment has a plate thickness of 0.6 bar to 1 bar.
．． It is constructed as shown in FIG. 3 using a 0m++ spring steel plate. Figure 4 shows the rank holder 10 in the direction of arrow C in Figure 3.
5 is a developed view, and the chain line in FIG. 5 indicates a line to be bent at a right angle. As shown in the side view (FIG. 4), the U-shaped bent portion 10b is a part that holds the rack 7, and its parallel 2
The face width dimension t is set to have an appropriate clearance with respect to the width dimension of the rack 7. The U-shaped bottom surface becomes a portion that supports the back surface of the rack 7, as will be described later. Appropriate cuts 10 are made on both sides of this U-shaped bottom part E (Fig. 5).
c is provided to form a plate spring-like tongue piece 10d.

When carrying out the present invention, the material constituting the rack holder is not limited to a spring steel plate as in this embodiment, but at least the tongue piece 10d is made of a material having spring elasticity.

FIG. 6 is a sectional view taken in the direction of arrow F shown in FIG. Through hole 10a of rank holder 10 configured as described above
is fitted onto the wiper shaft 8 and assembled, and the rack 7 is slidably held by the folded folded part fob. 11) 1 casing (C integrally molded boss part, 12 C bearing sleeve fitted to the above boss part, 13 casing lid, 14
is a bearing sleeve fitted into the above-mentioned canong lid.

As mentioned above, the rank holder 10 is fitted onto the wiper shaft 8, and the rank 7 is held by the rank holder 10, so that the rack 7 is prevented from meshing with the binion 9 fitted on the wiper l111]8. Retained. Then, as shown in FIG. 2, fold up the tongue piece 10d formed on the rank holder lO, and slide the leaf spring-like tongue piece 10d on the back of the rank 7, and its elasticity will cause the rack 7 to be attached to the pinion 9. Toward (to move toward)

In this embodiment, as described above, a through hole 10a is formed in the spring steel plate Q' having elasticity to fit into the wiper shaft 8, and a U-shaped portion 10b for holding the rack 7 is formed. A plate spring-like tongue piece i0d is formed at a location where the rank holder io faces the rear surface of the rack 7, and the bending elasticity of this tongue piece 10d allows the rack 7 to be attached to the binion 9. energize towards.

The rank holder 10 is extremely easy to assemble because it is simply connected to the wiper shaft 8 and fitted with the through hole 10a.
Since the rank holder 10 is not restrained with respect to the rotation direction with respect to the wiper shaft 8, it does not interfere with the rotation of the wiper shaft 80, and the rank holder 10 itself does not interfere with the wiper shaft 80.
It can be freely rotated around.

However, the rack 7 holder 1o holds the rack 7 by the fold-back shaped part lob, and its posture in the direction of rotation is restricted by the rack 7, and when the rack 7 rotates back and forth, it also rotates back and forth. do.

Since the holding mechanism in the motor unit case of this embodiment is configured as described above, the rack 74 is held by the rank holder 10 and meshed directly with the pinion 9, and is displaced in the direction of the tooth width. There is no damage. Moreover, since the tongue piece 10d in the form of a leaf spring is biased toward the pinion 9, even if the tooth surface or other sliding surface is abraded, the pinion will not cause a large crush at the gear meshing part. 9 for smooth transmission operation.

As described in detail above, when the present invention is applied, there is no risk of excessive cracking between the rank and the binion, and the rank can move back and forth while smoothly responding to the rotation of the rank. An excellent gear holding mechanism in a motor unit case equipped with a 12-rank guide means that is easy to assemble and has a simple structure that can guide the movement and maintain a normal one-coupling relationship with the pinion. produce an effect.

[Brief explanation of drawings]

Figures 1 to 6 show the implementation of the gear holding mechanism in the motor unit case according to the present invention, Figure 1 is a plan view of the deaf with the lid of the motor unit case removed, and Figure 2 is a rank Figure 3 is a front view of the rank holder, Figure 4 is a side view of the same, Figure 5 is a developed view of the same, Figure 6 is an arrow F shown in Figure 1. FIG. 1...Motor unit case, 2...Motor, 3
...Reduction gear mechanism, 4...Final stage receiving gear, 5...
・Eccentric cam, 6...cam follower, 7...rank,
8... Wiper shaft, 9... Binion, 10... Rank holder, 10a... Through hole drilled in rank holder, l
Ob...Fold-shaped part of the rank holder, loc...notch of the rack boulder, lod...plate spring-like tongue piece formed on the rank holder, 11...boss part, 12, 14...
...Bearing sleeve, 13...Housing lid. Patent applicant Honda Motor Co., Ltd. Ichikoh Industries Co., Ltd. Agent Patent attorney Tadashi Akimoto Figure 1 q Figure 3 Figure 4 Figure 5 Figure 6

Claims (1)

[Claims] In a gear mechanism in a motor unit case that engages a rack with a pinion fitted to a wiper shaft and causes the above-mentioned rank to reciprocate by a crank means to drive the wiper shaft in reciprocating rotation, a plate-like member having elasticity is used. In addition to forming a U-shaped part that holds the rank, a transparent hole that fits with the shaft is formed to form the rank holder, and a plate/plate is provided at the location where the rank holder faces the back of the rack.
A gear holding mechanism in a motor unit case, characterized in that a shin-like tongue piece is formed, and the rack is biased toward a pinion by the bending elasticity of the tongue piece.