JPH0436735A - Motor-driven diaphragm device - Google Patents

Abstract

PURPOSE:To reduce the cost of producing a motor by making a printed wiring board function as a bearing. CONSTITUTION:The motor is constituted of a magnetic rotor 3 fixed on a rotor shaft 4, bobbins 2a and 2b arranged on the outer peripheral part of the rotor 3 and a fixed yoke 6. The rotor shaft 4 is turnably axially supported by the bearing 1a of a bottom board 1 and the printed wiring board 5. As to the printed wiring board, a pattern is applied on its surface and a bearing hole is formed in its center part. A pattern copper foil is applied to the outer peripheral part of the bearing hole and through hole plating is performed to a circumferential surface. Since the plating is performed to the bearing hole, durability and sliding ability are improved.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to an electric aperture device in which aperture blades are driven by rotation of a rotor shaft.

[Prior Art] A conventional electric diaphragm device of this type is generally constructed as shown in FIG. That is, the pair of aperture blades 16.1
7 is housed between the base plate 1 and the lid 19 so as to be movable in the axial direction. This movement is driven by the swinging of the drive arm 14. The motor is composed of a rotor 3, a stator 6, an insulating tape, etc., and one of the rotor shafts 4 is supported by a bearing 1a on a base plate, and the other is supported by a shaft hole 12a formed in a cap 12. .

Therefore, when the rotor shaft 4 of the motor rotates, the drive arm 14 swings against the return spring 15, and the aperture blades 16.1 move appropriately in the axial direction to narrow the aperture by a predetermined amount.

[Problems to be Solved by the Invention] Since the rotor shaft of an electric throttle device is generally supported by a bearing as described above, there are various problems with this bearing part.

That is, since a cap is required as a bearing and its manufacturing cost is high, there is a drawback that the cost of the entire electric diaphragm device increases. In addition, the cap increases the overall height and weight of the motor, and since the cap is made of a molded product, shaft friction and torque loss are large in high or low temperature environments, and the power supply is small. Motors also have the problem of having an adverse effect on blade operation ripple and the like.

Therefore, an object of the present invention is to provide an electric diaphragm device that can be manufactured at low cost and compactly. Another object of the present invention is to provide an electric diaphragm device that is lightweight and can be driven even by a motor with a small drive torque, that is, a small capacity.

[Means for Solving the Problems] In order to achieve the above object, the present invention provides that at least one shaft of a rotor shaft that drives the aperture blades is supported by a shaft hole formed in a printed wiring board, and the shaft is The holes are through-hole plated.

[Function] Since the rotor shaft of the motor according to the present invention is also supported, it rotates in the same manner as the conventional motor and drives the aperture blades appropriately.

By the way, according to the present invention, the printed wiring board is also used as a bearing material, and there is no need for a cap or other dedicated member as a rotor support member, so the number of assembly and manufacturing steps can be greatly reduced compared to conventional electric diaphragms. can be reduced.

In addition, it is possible to make the electric throttle device smaller and lighter at the same time as the motor is smaller and lighter, and manufacturing costs can also be significantly reduced. Further, by reducing the shaft friction loss torque, it is possible to suppress the occurrence of operational ripples.

[Embodiment] Hereinafter, one embodiment of the present invention will be described with reference to FIGS. 1 to 3. The motor is composed of a magnet rotor 3 fixed to a rotor shaft 4, bobbins 2a and 2b arranged around its outer circumference, a fixed yoke 6, and the like. The rotor shaft 4 is rotatably supported by a bearing 1a of the base plate 1 and a printed wiring board 5.

As shown in FIG. 3, the printed wiring board has a pattern 7 on its surface and a bearing hole 8 formed in the center. A patterned copper foil 9 is applied to the outer periphery of the bearing hole 8, and through-hole plating 11 is applied to the circumferential surface. Since the bearing hole is plated in this way, durability and slidability are improved.

The rotor shaft 4, which is supported as described above, drives the aperture blades via a drive arm or the like, as described with reference to FIG.

[Effects of the Invention] As explained above, by providing the printed wiring board with a bearing function, the height can be lowered and more compact than the conventional electric diaphragm meter, and the weight can also be reduced by the amount of the cap. can. Furthermore, since there is no cap, both the man-hours and manufacturing cost for manufacturing the motor can be significantly reduced compared to conventional products.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing one embodiment of the present invention, and is a sectional view taken along arrow A-A in FIG. 2, and FIG. 2 is a plan view thereof.
FIG. 3(a) is a plan view showing an embodiment of the printed wiring board, FIG. 3(b) is a sectional view taken along arrow B-B in FIG. 3(a), and FIG. 4 is an exploded perspective view showing a conventional example. It is a diagram. 4... Rotor shaft 5... Printed wiring board 8.
...Shaft hole 11...Through hole plating (part) and 4 others Fig.

Claims (1)

[Claims] 1. In an electric diaphragm device in which aperture blades are driven by rotation of a rotor shaft, at least one of the rotor shafts is supported in a shaft hole formed in a printed wiring board, and the shaft hole is An electric diaphragm device characterized by through-hole plating.