JPH025147Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a gear for transmitting rotational force, particularly a synthetic resin gear suitable for use in a motor actuator that moves a damper or the like of an automobile air conditioner.

As this kind of gear, for example, Utility Model No. 56-131053
As shown in the publication, a gear body and a support shaft integrally made of synthetic resin are known, and this known conventional example is applied to the output gear of a motor actuator. is shown in FIG.

In FIG. 1, boss parts 10, 10 are provided on the upper and lower surfaces of the gear body 9, and the upper part of the support shaft 11 is formed integrally with the gear body 9 and the boss part 10 from synthetic resin on the upper boss part 10. has been done. Also,
A support shaft 11 is provided with a metal member inserted into a shaft fitting groove 20 so that the lower part of the support shaft 11 projects from the boss portion 10 on the lower surface.

The upper and lower parts of the support shaft 11 are supported by bearings 12 and 12 of the upper case 1a and the lower case 1b, respectively, and a lever coupling part 17 is provided at the upper end of the support shaft 11 integrally with the support shaft 11. The lever coupling portion 17 protrudes to the outside of the upper case 1a. Then, another gear 21 meshes with the output gear 8, and a lever (not shown) of the link device is attached to the lever coupling portion 17, so that the rotation from the other gear 21 is decelerated and transmitted to the link device. is configured to be

However, the gear with the above configuration has a support shaft 11
Since the upper part of the support shaft 11 is made of synthetic resin, if the transmission system after the output gear is locked, there is a risk that the support shaft 11 will be deformed by receiving large torque.

Therefore, the object of this invention is to provide a synthetic resin gear whose rotating shaft does not deform even when subjected to large torque. In a synthetic resin gear made of synthetic resin, the support shaft passing through the gear body is covered with a metal pipe, and the metal pipe, the gear body, and the support shaft are integrally formed. The synthetic resin gear is characterized in that the metal pipe is held between the gear body and the support shaft. Therefore, when a torque is applied, since the support shaft on which the largest torsional moment acts is covered with a metal pipe, it can sufficiently withstand a large torque, and therefore the above object can be achieved.

Examples of this invention will be described below with reference to the drawings.

In FIG. 2, a motor actuator is shown, and a case 1 of the motor actuator is constructed by combining an upper case 1a and a lower case 1b, and the outside of the upper case 1a is covered with a cover 1c. A motor housing chamber 2 and a gear train housing chamber 3 are formed within this case 1.

A motor 4, which is a DC electric motor, is installed in an upper case 1a and a lower case 1b in a motor storage chamber 2 of a case 1.
The rotating shaft 4a thereof protrudes toward the gear train storage chamber 3.

The gear train 5 is housed in the gear train storage chamber 3, a worm 6 is fixed to the rotating shaft 4a of the motor 4, and an intermediate gear 7 is meshed with the worm 6.

The intermediate gear 7 includes a worm wheel portion 7a that meshes with the worm 6, and a worm wheel portion 7a that meshes with the worm 6.
a and a worm part 7b formed integrally with the worm part 7b,
An output gear 8 meshes with this worm portion 7b, and this invention is applied to this output gear 8.

The output gear 8, which is a gear made of synthetic resin, has boss portions 1 on the upper and lower surfaces of the gear body 9, as shown in FIG.
0 and 10 are provided, and a support shaft 11 that supports the gear body 9 is provided protruding from the boss portions 10 and 10.

The upper and lower parts of the support shaft 11 are a bearing part 1 formed to face the upper case 1a and the lower case 1b.
The support shaft 11 is supported by shaft support holes 13 and 14 of No. 2 and 12, and the periphery of the support shaft 11 is covered with a metal pipe 15.

Therefore, this metal pipe 15 is connected to the shaft support hole 1.
3 and the shaft support hole 14.

In this embodiment, the metal pipe 15 is
A through hole 16 is formed that passes through the gear body 9 and communicates between the gear body 9 and the support shaft 11, and the gear body 9 and the support shaft 11 are of the same type through the through hole 16 by insert molding. It is composed of synthetic resin.

Further, a lever coupling part 17 is provided at the upper end of the support shaft 11 integrally with the support shaft 11, and the lever coupling part 17 protrudes to the outside of the case 1, and a lever (not shown) of the link device is attached to the lever coupling part 17. There is.

In the above configuration, when the motor 4 rotates, the worm 6, the intermediate gear 7, and the output gear 8 rotate in order, and the support shaft 11 is rotated. It is output from 17. Therefore, although torque always acts on the support shaft 11, since the support shaft 11, on which the maximum torsional moment acts, is covered with a metal pipe, it will not deform even after long-term use. Further, when the output transmission system after the support shaft 11 is locked, a large torque acts on the support shaft 11, but it does not deform for the same reason as mentioned above.

In FIG. 4, another embodiment of the invention is shown, in which, compared to the previous embodiment, a metal pipe 15 is not provided with a through hole.
The difference is that the gear body 9, the boss parts 10, 10, and the support shaft 11 are each made of a different type of synthetic resin depending on the function of the member, as described below. That is, the gear body 9 and the boss portion 1
0 and 10 are made of, for example, nylon resin, which has low frictional resistance and good durability and lubricity, and the support shaft 11 is made of, for example, acetal resin, which has high mechanical strength.

The other configurations are the same as those of the embodiment described above, so explanations thereof will be omitted, but this embodiment also provides the same functions and effects as those of the embodiment described above. Furthermore, in this embodiment, the gear main body 9 and the support shaft 11 are made of synthetic resin according to their functions, with the metal pipe 15 as a boundary, so that a gear with excellent durability and strength can be provided. It is something.

As described above, according to this invention, since the support shaft is surrounded by a metal pipe, it can sufficiently withstand large torques without deformation.

In addition, since the support shaft is surrounded by a metal pipe, the parting line formed on the surface of the support shaft is covered by the metal pipe, and the metal pipe comes into contact with the bearing, allowing the support shaft and bearing to This has the effect of reducing frictional resistance.

Furthermore, in the past, the support shaft was made thick to increase the strength of the support shaft, so there was a risk of warping, but with this invention,
Since it is reinforced with a metal pipe, there is no need to make the support shaft thick, so there is no risk of warping, and the weight is also reduced.

[Brief explanation of the drawing]

Figure 1 is a sectional view of a conventional synthetic resin gear; Figure 2 is a sectional view of a motor actuator in which the synthetic resin gear of this invention is applied to the output shaft;
The figure is a sectional view of the above-mentioned synthetic resin gear, and FIG. 4 is a sectional view of the synthetic resin gear showing another embodiment. 9...Gear body, 11...Support shaft, 15...Metal pipe, 16...Through hole.

Claims (1)

[Claims for Utility Model Registration] 1. A synthetic resin gear in which a gear body and a support shaft supporting the gear body are made of synthetic resin, in which the periphery of the support shaft passing through the gear body is made of metal. A synthetic resin gear covered with a pipe, the metal pipe, the gear body, and the support shaft being integrally formed, and the metal pipe being held between the gear body and the support shaft. 2. Utility model registration in which the metal pipe is formed with a through hole that communicates between the gear body and the support shaft, and the gear body and the support shaft are made of the same type of synthetic resin through the through hole. A synthetic resin gear according to claim 1. 3. The synthetic resin gear according to item 1 or 2, wherein the metal pipe separates the gear body and the support shaft, and the gear body and the support shaft are made of different types of synthetic resin.