JPH0116001Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a rotation angle control mechanism for an actuator for an air conditioner, and particularly to a variable resistance device whose resistance value changes in accordance with rotation of an output gear.

Conventionally, as shown in FIG. 1, an actuator for an air conditioner has a printed circuit board 2 disposed on the surface side of a lower case 1, and a resistor piece 4 arranged approximately in a circle on the surface of the printed circuit board 2 that faces the output gear 3. A brush 5 provided in an arc shape and in contact with the resistance piece 4, a brush 7 in contact with a conductive piece 6 provided along the resistance piece 4 on the front side of the printed circuit board 2, and an output gear 3.
The brushes 5 and 7 are brought into contact with the resistive piece 4 and the conductive piece 6, so that the resistance value obtained between the resistive piece 4 and the conductive piece 6 changes based on the rotation of the output gear 3. By detecting this change in resistance, the rotation angle of the output gear 3 is automatically detected. Note that a connector, a motor holding plate 9, and the like are arranged on the upper side of the lower case 1.

However, according to the above configuration, since the resistor piece 4 is made of a material that is relatively easily worn, mainly carbon, etc., the brush 5 slides on the resistor piece 4 for a long period of time, so that the surface side of the resistor piece 4 is damaged. As a result of this wear, the resistance change characteristics of the resistor piece 4 change, making it impossible to detect a normal rotation angle. For this reason, it has become impossible to accurately control air control doors, such as an inside/outside air switching door, an air mix door, a mode switching door, etc., which are driven by the output gear 3 via a link (not shown). Further, due to the abrasion of the resistor piece, the abraded powder adheres to other parts and deteriorates these parts.

The purpose of this invention is to derive a plurality of conductor patterns from a resistor piece constituting a variable resistance device, and to eliminate the above-mentioned drawbacks by sliding a brush for resistance value detection provided on an output gear against the conductor patterns. This will be explained in detail below using examples.

FIGS. 2 to 5 show an embodiment of the rotation angle control mechanism for an actuator for an air conditioner according to the present invention, and in the figure, reference numeral 10 indicates a resistance value that changes depending on the rotation angle of the output gear. It is a variable resistance device. This consists of a resistor 12 printed linearly on the surface side of a printed circuit board 11 installed on the case side that houses the motor, intermediate gear, output gear, etc. that constitute the actuator for the air conditioner, and this resistor piece 12. One end is equally distributed and drawn out in a straight line and printed, and each tip side is extended in the direction of a hole 22 that holds the output shaft of an output gear (not shown), and is printed along a circumference centered on this hole 22. A conductor pattern 13 forming a brush contact portion 13a to be arranged, and a contact portion 13 of this conductor pattern 13.
a conductive piece 20 provided along the inside circumference of a;
The brush 14 is provided on the output gear and connected to each other, and includes a brush 14 that contacts the contact portion 13a and a brush 21 that contacts the conductive piece 20. Above conductor pattern 1
3 is printed in the same process as the resistor piece 12 is printed on the printed circuit board 11, and the material used is copper foil or the like. Above contact part 1
The width of 3a is gradually wider at both ends than at the center. As the brushes 14 and 21 move in the circumferential direction, the resistance value obtained between the terminals 23 and 25 or between the terminals 25 and 24 changes. According to this embodiment, as shown in FIG. 4, the link 27 is moved by the rotation of the lever 26 provided on the output shaft of the output gear, thereby controlling the air as a control object in the vehicle air conditioner. Control door 28 and the like can be controlled. Also, due to the rotation of the output gear, the contact portion 13a, which is the tip portion of the conductor pattern 13 of the brush 14,
The contact position changes. That is, Figure 5a
As shown in FIG. 2, when the link 27 and the lever 26 are at a right angle, that is, in a range where the motor input is small and the rotation angle is small, the brush 14 comes into contact with the contact portion 13a at a location corresponding to approximately the center of the resistance piece 12. However, as the lever 26 gradually rotates from this position and the rotation angle becomes larger, the brush 14 gradually becomes wider at the abutting portion 13a on the end side.
It will come into contact with. In this manner, as the contact portion 13a is brought into contact with a wider width, the amount of change in the resistance signal obtained from the variable resistance device 10 gradually becomes smaller, as shown by characteristic l. Therefore, in the present application, when the output gear is controlled based on the resistance signal obtained from such a variable resistance device 10,
The movement stroke of the link 27 is determined by the characteristic n in Fig. 5b.
It can be controlled linearly as shown in . The reason is as follows. That is, normally, when controlling the air control door 28, the control unit 30 controls the motor input so that the resistance value (resistance signal) corresponding to the rotation angle of the output gear obtained from the variable resistance device matches the target value. to control the motor rotation speed. In this case, conventionally, the resistance signal changes linearly based on the characteristic m shown in Fig. 5a in response to motor input control, so the change in the moving stroke of the link in response to such a resistance signal is as shown in Figs. 5a and b. Characteristic o
The curve changes as shown in the figure. Therefore, in the present application, in order to linearize the moving stroke of the link with respect to the resistance signal as shown in the characteristic n of FIG. 5b, the conventional relationship ΔW between the characteristic o and the characteristic m is always proportional to the rotation angle θ. In order to show the relationship, the change in the resistance signal with respect to the motor input is made into a curve by making a correction in advance as shown in the characteristic 1. Due to this characteristic 1, a proportional relationship is obtained between the characteristics 1 and n, and the result is linearity can be obtained. When linearity is given to the travel stroke of the link 27, the air control door 2
8 can be controlled accurately and precise air conditioning control can be performed.
Further, when the conductor pattern 13 is formed from copper foil or the like, the copper foil does not wear out as easily as compared to the resistor, so there is no possibility that worn powder will adhere to other parts and cause the parts to deteriorate. In this embodiment, the control of the air control door 28 has been described, but the present invention can also be applied to control objects that are linked via other links.

As explained above, according to the rotation angle control mechanism for an actuator for an air conditioner of the present invention, the brush for resistance value detection that moves along the circumferential direction in conjunction with the output gear is provided, and the brush is arranged in a straight line. The brush has a plurality of conductor patterns, one end of which is equally distributed on a resistive piece printed on the resistive piece, the other end of which is led out from the resistive piece, and the contact portion of the other end is arranged along the movement direction of the brush. abut against the above contact part,
A change in the resistance value of the resistor piece due to a change in the rotation angle of the output gear is detected through this conductor pattern, and the contact portion of the conductor pattern is gradually wider toward both ends than toward the center. The change in the width of the abutting part changes in such a way that the movement stroke of the link shows almost linearity with respect to the resistance signal, so it is possible to give almost linearity to the movement of the link. Objects to be controlled can be precisely controlled via the Further, the parts will not deteriorate due to wear powder.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing an example of a conventional rotation angle control mechanism for an actuator for an air conditioner, and FIGS. 2 to 5 a and b show a rotation angle control mechanism for an actuator for an air conditioner according to the present invention. FIG. 1 is a perspective view, a circuit diagram, a plan view, and a characteristic diagram showing one embodiment. 10... Resistance variable device, 11... Printed circuit board, 13... Conductor pattern, 14... Brush, 1
5, 16... Branch part, 13a... Contact part, 2
6... Lever, 27... Link, 28... Air control door (object to be controlled).

Claims (1)

[Scope of utility model registration request] Control is performed by decelerating the rotational force of the motor to rotate the output gear 3, moving the link 27 connected to the tip side of the lever 26 that rotates in conjunction with the output gear 3, and interlocking with the link 27. A rotation angle control mechanism for an actuator for an air conditioner that controls the rotation angle of an object includes a brush for detecting a resistance value that moves along the circumferential direction in conjunction with the output gear 3, and a linear brush. A plurality of conductor patterns 13 are provided, one end of which is equally distributed on a resistor piece printed on the resistor piece, the other end of which is led out from the resistor piece, and the contact portion 13a of the other end is arranged along the movement direction of the brush, The brush is brought into contact with the contact portion 13a, and a change in the resistance value of the resistor piece due to a change in the rotation angle of the output gear 3 is detected via the conductor pattern 13. The contact portion 13a is set to be gradually wider toward both ends than toward the center, and changes in the width of the contact portion 13a are such that the movement stroke of the link 27 exhibits approximately linearity with respect to the resistance signal. A rotation angle control mechanism for an actuator for an air conditioner, which is characterized by changing the rotation angle.