JPS6332419Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) This invention relates to a motor actuator used mainly to move an air mix door, an inside/outside air switching door, and other doors of an automobile air conditioner.

(Prior Art) A motor actuator transmits rotation of a motor in one direction or in forward and reverse directions to an output shaft via a gear device, and is known per se from, for example, Japanese Utility Model Application Publication No. 57-146765. Conventional examples thereof are shown in FIGS. 1 and 2.

In FIGS. 1 and 2, the intermediate gear 6 constituting the gear device has a worm wheel portion 6a that meshes with the worm 5 on the input side, and a worm portion 6b that meshes with the gear on the output side (not shown). It is formed. The support shafts 8, 8 on both sides of the intermediate gear 6 are covered with cap-shaped bearings 9, 9, and the bearings 9, 9 are attached to the bearing portions 10, 10 of the case 1.
The intermediate gear 6 is supported by the case 1,
It is designed to rotate smoothly.

(Problem to be Solved by the Invention) However, in the past, there was a problem that abnormal noise was generated from the vicinity of the intermediate gear 6. The reason for this is the intermediate gear 6 due to manufacturing technology and cost.
Support shafts 8, 8, bearings 9, 9 and bearing part 1
Since a certain error is allowed for each dimensional accuracy of 0 and 10, a gap of, for example, about 0.5 to 1 mm exists between each member, and the bearings 9 move freely within this gap. This is due to the fact that the intermediate gear 6 and the bearings 9, 9 move in response to the various external forces described below. That is, first, the bearings 9, 9 receive the operation of a motor (not shown in FIG. 1) via the worm 5 and the intermediate gear 6, and vibrate while being rotated by the intermediate gear 6. Second
The intermediate gear 6 meshes with the worm 5 on the input side through the worm wheel portion 6a, and the gear on the output side through the worm portion 6b, so that the action on the input side and the reaction on the output side are transferred to the intermediate gear. 6 is received in the axial direction, and moves in the axial direction due to fluctuations in input and load, so the bearings 9, 9 also move in the axial direction,
The motor resonates to increase the amplitude of vibration. Thirdly, in the case of a type in which the motor rotates in forward and reverse directions, the worm part 6b of the intermediate gear 6 has a lead angle of angle θ, and if the rotation direction of the intermediate gear 6 changes, the intermediate gear Since one of the support shafts 8, 8 of the gear 6 moves upward and the other moves downward, the meshing state between the intermediate gear 6 and the gear on the output side changes and abnormal noise is generated.

Therefore, the object of this invention is to prevent the generation of abnormal noise caused by the movement of the intermediate gear and the bearing as described above.

(Means for solving the problem) This invention is equipped with a gear device that transmits the rotation of the motor to the output shaft, and the worm wheel portion in which the worm on the input side meshes with this gear device and the gear on the output side mesh with the gear device. In a motor actuator having an intermediate gear integrally formed with a worm part, a cap-shaped bearing is mounted on at least one support shaft of the intermediate gear, and this bearing is received by a bearing part of a case. , the bottom surface of the bearing is formed to be inclined, and the end surface of the bearing portion of the case is formed to be inclined in accordance with the bottom surface of the bearing,
A pressing structure in which a spring is interposed between a fixing means formed by fitting the bottom surface of the bearing into the end surface of the bearing portion, the support shaft of the intermediate gear and the bearing, and the spring presses the bearing against the end surface of the case. It is characterized by.

(Function) Therefore, when rotation is transmitted to the intermediate gear,
The support shaft of the intermediate gear rotates within the bearing while receiving the downward reaction force of the spring from the end face of the bearing, but the bearing does not rotate because its bottom face is inclined and fits with the end face of the case. Also, since the bearing is pressed by a spring, it hardly vibrates due to vibrations of the motor or the like.

(Example) Hereinafter, an example of this invention will be described with reference to the drawings.

An embodiment of this invention is shown in FIGS. 3 to 7, and the case 1 is constructed by adhesively fixing an upper case 1a and a lower case 1b at their dividing surfaces.

The case 1 houses a motor 2 and a gear device 4 that transmits the rotation of the motor 2 to an output shaft 3.

The gear device 4 includes a worm 5 fixed to the rotating shaft 2a of the motor 2, an intermediate gear 6 that meshes with the worm 5, and an output gear 7 that meshes with the intermediate gear 6. The output shaft 3 is fixed to the center of the shaft.

The intermediate gear 6 is integrally formed with a worm wheel portion 6a in which the worm 5 on the input side meshes with a worm portion 6b in which the output gear 7 on the output side meshes, and at least one support shaft 8 of the intermediate gear 6 is formed.
A cap-shaped bearing 9 is mounted on the case 1, and the bearing 9 is received by a bearing portion 10 of the case 1, which will be described below.

In addition, in this embodiment, the support shafts 8 on both sides,
8 is covered with bearings 9, 9.

The bearing parts 10, 10 of the case 1 are connected to the lower case 1b.
At the upper ends of the vertical parts 11, 11 provided opposite to the
A groove 12 having a back wall is formed, the upper surface of the groove 12 is closed by the upper case 1a, and a bearing 9 is inserted into the groove 12.
The bearing 9 is fixed to the case 1 by means of a fixing means 13.
is fixed.

As shown in FIGS. 6 and 7, the fixing means 13 is formed so that the bottom surface of the bearing 9 is inclined from above to below, and the upper case of the bearing part 10 is formed so as to correspond to the bottom surface of the bearing 9. The end face of the bearing portion 1a is formed to be inclined, and the bottom face of the bearing 9 is fitted to the end face of the bearing portion 10.

Further, the fixing means 13 is a support shaft 8 of the intermediate gear 6.
A recess 18 is formed in the end face of the support shaft 8.
A pressing member 20 of a spring 19 is interposed between the bearing 8 and the bearing 9, and has a pressing structure in which the spring 19 presses the bearing 9 against the end surface of the upper case 1a.

In the above configuration, when rotation is transmitted to the intermediate gear 6, the support shaft 8 of the intermediate gear 6 rotates within the bearing 9 while receiving a downward reaction force of the spring 19 from the end surface of the bearing 9. does not rotate because its bottom surface is inclined and fits with the end surface of the case 1, and the spring 19
Since the bearing 9 is pressed by the motor 2, the bearing 9 hardly vibrates due to the vibration of the motor 2 or the like.

Further, when a large load is applied to the output side of the intermediate gear 6 and an axial force acts on the intermediate gear 6, and the intermediate gear 6 attempts to displace in that direction, the spring 1 resists the displacement.
The elastic force 9 acts to prevent the intermediate gear 6 from being displaced in the axial direction, and the vibrations of the intermediate gear 6 do not resonate with the vibrations of the motor 2 and generate abnormal noise.

Furthermore, when the rotation of the intermediate gear 6 is reversed, as in the previous embodiment, the support shaft 8 of the intermediate gear 6 is subjected to a force in a different radial direction and attempts to displace, but is not displaced because it receives a reaction force from the spring 19 in the downward direction, and the meshing state between the intermediate gear 6 and the other gears remains unchanged.

According to this embodiment, since the bearing 9 is pressed against the end face of the case 1 by the spring 19, the intermediate gear 6 receives spring force from both sides due to the reaction, so that the intermediate gear 6 does not oscillate in the axial direction. In addition, even if a large torque is applied to the output side, it is possible to move in the axial direction against the spring force, so that the impact caused by the large torque can be alleviated and the startability is benign. Further, since the spring 19 is interposed between the support shaft 8 of the intermediate gear 6 and the bearing 9, there is also an effect that some backlash in the thrust direction during manufacturing can be absorbed.

(Effects of the invention) Since the bottom surface of the bearing fits into the inclined end surface of the bearing part, and a spring is also interposed between the support shaft and the bearing, it is possible to suppress vibration and prevent the generation of abnormal noise, and it is possible to suppress vibrations in the thrust direction. can absorb the looseness of

[Brief explanation of the drawing]

Figures 1 and 2 show conventional embodiments;
The figure shows a sectional view of the motor actuator, FIG. 2 shows a sectional view of the bearing part of the intermediate gear, FIGS. 3 to 7 show embodiments of this invention, and FIG. 4 is a vertical sectional view of the motor actuator, FIG. 5 is an exploded perspective view of the bearing portion of the intermediate gear, and FIG. 6 is a sectional view of the bearing portion of the intermediate gear showing another embodiment. Figure 7 is A of Figure 6.
-A cross-sectional view. 1... Case, 2... Motor, 4... Gear device, 5... Worm, 6... Intermediate gear, 6a...
Worm wheel part, 6b... Worm part, 8...
...Support shaft, 9...Bearing, 9a...Cylindrical side surface of bearing, 10...Bearing portion, 19...Spring.

Claims (1)

[Scope of utility model registration request] The gear device is equipped with a gear device that transmits the rotation of the motor to the output shaft, and the gear device has an intermediate gear in which a worm wheel portion that meshes with the worm on the input side and a worm portion that meshes with the gear on the output side are integrally formed. In a motor actuator in which a cap-shaped bearing is mounted on at least one support shaft of the intermediate gear, and this bearing is received by a bearing part of the case, the bottom surface of the bearing is formed to be inclined, and this A fixing means is formed by forming an end face of a bearing part of the case to be inclined corresponding to a bottom face of the bearing, and fitting the bottom face of the bearing to the end face of the bearing part, and a support shaft of the intermediate gear and the bearing. A motor actuator characterized in that it has a pressing structure in which a spring is interposed, and the spring presses the bearing against the end surface of the case.