JPH09190906A - Rotation throttle position sensor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent deformation of a sash by providing a rotation stoppage part which forms a flat plane on a part of a cylindrical rotor whose bottom telescope a guide part of a case bottom by thickness, and providing a thin part on both sides of the rotation stoppage part, so that rotor breakage is prevented when assembling into a rotational throttle shaft. SOLUTION: A guide part 21 consisting of a cylindrical protruding part is provided on the center of the inner bottom part of a cylindrical case 20 with bottom which is molded from synthetic resin, superior in heat resistance and machine force, into which glass fiber is mixed. And, a cylindrical rotor 33 consisting of the synthetic resin into which glass fiber is mixed is assemble into the case 20, and a protruding part 34 is provided toward the outside on the intermediate part of the outer periphery of the rotor 33, and on the inside facing the part provided with the protruding part 34, a rotation stoppage part 36 on which a flat surface formed by thickness is formed. And further, a thin part 39 is formed on both sides of the thick rotation stoppage part 36, and when a rotational throttle shaft 41 which is so cut as to have a flat surface part 40 on a surface is pressed in, the rotation stoppage part 36 is bent outside.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotary throttle position sensor used for detecting the position of a rotary throttle shaft of an internal combustion engine.

[0002]

2. Description of the Related Art An internal combustion engine such as a vehicle uses a throttle valve to control the amount of air flowing into the engine. When the throttle valve is opened, a large amount of air is sucked in, and when the throttle valve is closed, a small amount of air is sucked in. The speed of the engine is controlled. The throttle valve is connected to an accelerator pedal and is opened / closed by depressing the accelerator pedal.

A conventional rotary throttle position sensor of this kind has been constructed as shown in FIGS. That is, the inner circumference of a bottomed cylindrical case 4 having a built-in connector terminal 1, a part of which is provided with a connector portion 2 protruding outward and a mounting portion 3 on the opposite side. A film resistor 7 having a resistance pattern 5 printed on its surface and a connection portion 6 to the connector terminal 1 provided at one end is housed, and the connection portion 6 of the film resistor 7 is connected to the connector terminal 1
A comb-shaped presser spring 8 bent into a U-shape for elastically pressing the inner surface of the case 4 is incorporated, and a projecting portion 9 on the outer periphery is attached to the center of the case 4.
The rotor 11 having the comb-shaped brush 10 attached to the resistance pattern 5 of the film resistor 7 is incorporated in the above, and the rotary throttle shaft is inserted in the center of the upper surface of the case 4,
It is constructed by incorporating a cover 13 having a central hole 12 so that it can be coupled with the rotor 11.

This rotating throttle shaft is used for the rotor 1.
1 has a shape having a flat part in a part to be fitted with 1. The rotor 11 fitted and coupled to the rotary throttle shaft has a circular shape on the insertion port side of the rotary throttle shaft and is slightly downward. When the rotary throttle shaft is inserted, a thin-walled portion 16 is provided at a boundary between the flat-walled portion 15 and the flat portion 14, and the thin-walled portion 16 has a substantially uniform and thin-walled fitting portion 15 having a flat portion 14. The thin portion 16 extends so that the fitting cylinder portion 15 is closely attached to the rotary throttle shaft.

[0005]

In the above-mentioned conventional structure, the rotor 11 can be flexibly fitted to the rotary throttle shaft and can be lightened, while the uniform and thin fitting tubular portion 15 is used. Since it is configured, the fitting cylinder portion 15 of the rotor 11 is damaged when the dimensional error between the rotary throttle shaft and the rotor 11 is large and the rotor 11 is forcedly fitted, and the rotor 11 is entirely entrusted in the direction of the rotary throttle shaft, that is, the rotation. Since it is assembled so as to be supported only by the throttle shaft, if the angle of the center of the case 4 and the angle of the rotating throttle shaft are misaligned during assembly, excessive stress may be applied to the brush 10 attached to the rotor 11. If the end of the rotor 11 is caught inside the case 4 and receives large stress, the rotor 11 itself may be damaged. There has been a Tsu was a problem.

An object of the present invention is to eliminate the above-mentioned conventional drawbacks and provide a highly reliable rotary throttle position sensor.

[0007]

In order to solve the above problems, the rotary throttle position sensor of the present invention has a resistor provided on the inner peripheral wall of a cylindrical case having a bottom and is connected to the end of the resistor. A rotor is provided with a connector terminal, a rotor on which a brush that abuts and slides on the resistor is attached to a part of the peripheral surface of the case, and a rotary throttle that is fitted and coupled to the rotor at the center of the opening of the case A cover having an opening through which the shaft is inserted is attached, and a fitting hole having a cylindrical rotation stop portion having a flat surface with a partially thick portion is formed from the insertion opening side of the rotary throttle shaft to the lower middle portion. The rotation stop portion is provided with thin portions on both sides thereof to absorb a dimensional difference from the rotary throttle shaft.

According to the present invention, a highly reliable rotary throttle position sensor can be obtained.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION According to the first aspect of the present invention, a resistor is provided on an inner peripheral wall of a bottomed cylindrical case, and a connector terminal connected to an end of the resistor is provided.
In this case, a rotor having a brush that abuts and slides on the resistor is attached to a part of the peripheral surface, and an opening through which a rotary throttle shaft fitted and connected to the rotor is inserted in the center of the opening surface of the case. The rotor is cylindrical and has a fitting hole having a rotation stopping portion having a flat surface partially due to the thickness from the insertion opening side of the rotary throttle shaft to the lower middle portion. A thin portion that absorbs a dimensional difference from the rotary throttle shaft is provided on both sides of the portion, which has an effect that the rotor is not damaged when the rotor is coupled with the rotary throttle shaft.

According to the second aspect of the present invention, a guide portion for guiding the lower end portion of the rotor is provided inside the case. With this configuration, the rotor and the case are assembled with each other when assembled on the rotary throttle shaft. Since it is positioned, the rotor will not be tilted with respect to the case, excessive stress will be applied to the brush, and the lower end of the rotor will not be caught by something in the case and damaged, improving reliability. Become.

An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is an exploded perspective view of an embodiment of a rotary throttle position sensor of the present invention, and FIG. 2 is a top view of the same.
FIG. 3 is a sectional view showing a state in which the rotary throttle shaft is connected.

In FIG. 1 to FIG. 3, reference numeral 20 denotes a bottomed cylindrical case molded from a synthetic resin having excellent heat resistance and mechanical strength, such as polybutylene terephthalate mixed with glass fiber. At the center of the bottom portion, a guide portion 21 composed of a cylindrical protrusion is provided.
In addition, several connector terminals 22 are incorporated in the case 20 by insert molding.
One end of the case 2 is exposed inside the case 20, and the other end is the case 2
A part of the outer peripheral surface of 0 protrudes into the connector portion 23 provided so as to protrude outward.

A ring-shaped flange 24 is formed on the outer peripheral surface of the case 20, and a mounting portion 26 having a mounting hole 25 is provided at a part of the flange 24 facing each other. Further, a step portion 27 is provided in the middle portion of the inner peripheral wall of the case 20.

In such a case 20, several resistance patterns 29 are provided on one surface of a resin film 28 such as a polyimide film, and the other end of the resistance pattern 29 is brought into contact with the connector terminal 22 to electrically conduct. A resistor 31 in which a connecting portion 30 for forming the connection is formed by printing is incorporated. That is, the resistor 31 is incorporated along the inner peripheral wall of the case 20 so that the vertical position of the resistor 31 is regulated by the step 27 so that the resistance pattern 29 comes inside. One end of the resistor 31 is inside the case 20 of the connector terminal 22. It is installed so that it is located at the part exposed.

The connecting portion 30 of the resistor 31 is connected to the connector terminal 22 by a U-shaped bent metal plate having elasticity such as stainless steel. One side is a flat plate and the other side is a pressing spring. By incorporating 32, the connecting portion 30
Is pressed against the exposed portion of the connector terminal 22.

A cylindrical rotor 33 made of synthetic resin such as polybutylene terephthalate mixed with glass fiber is incorporated in the case 20. This rotor 33
Is provided with an outward protruding portion 34 at the middle portion of the outer peripheral surface, and the resistance pattern 29 of the resistor 31 is provided at the tip of the protruding portion 34.
The brush 3 that comes into contact with the brush 33 and slides by the rotation of the rotor 33
5 are attached.

A rotation stopper 36 having a flat surface is formed on the inner side of the side facing the portion where the protrusion 34 is provided. That is, the fitting hole 37 that is formed by cutting a part of a circle is formed in the center of the rotor 33. Further, the rotation stopping portion 36 is formed from the upper end to the lower portion of the intermediate portion, and the portion below that is fitted into the guide portion 21 of the case 20 and is supported by the perfect circular center hole 38.
Are formed.

Further, thin portions 39 are formed on both sides of the thick rotation stopping portion 36, and when the rotary throttle shaft 41 cut so as to have the flat portion 40 on one surface is press-fitted, the rotation stopping portion 36 is pressed. Is configured to flex outward, that is, to absorb the dimensional difference between the rotary throttle shaft 41 and the fitting hole 37.

A cover 42 made of the same material as the case 20 is attached to the opening of the case 20 in which the resistor 31, the pressing spring 32, and the rotor 33 are incorporated. An opening 43 through which the rotary throttle shaft 41 is inserted is provided at the center of the cover 42.

The rotary throttle position sensor thus constructed is preassembled, and is press-fitted into the rotary throttle shaft 41 near the internal combustion engine while aligning it, and the rotor 33 is attached to the rotary throttle shaft 41.
The mounting portion 26 of the case 20 in a state in which the
The case 20 is fixed to the throttle main body 44 by using, and the assembling is completed.

That is, with the flat portion 40 of the rotary throttle shaft 41 and the rotation stop portion 36 of the rotor 33 aligned, the rotary throttle shaft 41 together with the case 20.
Rotating throttle shaft 4 by pushing it to the side
The rotor 33 is fitted to the tip of the casing 1 and is coupled in the rotating direction.
Using the mounting part 26 of the
0 is fixed.

As a result, the rotary throttle shaft 41 rotates by stepping on the accelerator or by freeing it, the rotor 33 rotates in synchronization with the rotation, and the brush 35 attached to the rotor 33 causes the resistance pattern of the resistor 31. The contact position with 29 is changed, and the connector terminal 2
The voltage corresponding to the contact position is obtained in FIG. 2, and the amount of fuel injected into the engine can be controlled by using the fluctuation of the voltage as a signal.

When assembled as described above, the rotor 33 has the case 2
Since the center hole 38 of a perfect circle is fitted into the guide portion 21 for positioning with respect to 0, and the rotor 33 itself has strength with the thick rotation stopping portion 36 and the protruding portion 34, On the other hand, if the central axes do not match, press-fit connection cannot be achieved, and correct assembly can be performed, the rotor 33 may be damaged when it is assembled, or the rotor 33 may be inclined with respect to the case 20 and the brush 35 may cause the brush 31 to come into contact with the resistor 31 of the case 20. It will be possible to prevent deformation by applying excessive pressure to the.

In the above embodiment, the case 2 is used.
Although the guide portion 21 composed of a cylindrical protrusion is described as an example in FIG. 0, if the bottom of the case 20 has a large thickness, a circular concave portion is provided and the lower end portion of the rotor 33 is fitted into the concave portion for positioning. May be.

Further, the resin film 2 is used as the resistor 31.
Although the case where the resistance pattern 29 is formed on No. 8 has been described, it goes without saying that the resistance pattern 29 may be directly formed on the inner wall surface of the case 20.

[0026]

Since the rotary throttle position sensor of the present invention is configured as described above, the rotor is not damaged or the brush attached to the rotor is not deformed when it is installed in the rotary throttle shaft. Highly responsive,
Moreover, the yield can be made excellent, and the industrial value is great.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view showing an embodiment of a rotary throttle position sensor of the present invention.

FIG. 2 is a top view with the cover removed.

FIG. 3 is a sectional view showing a state in which the rotary throttle shaft is assembled.

FIG. 4 is an exploded perspective view showing a conventional rotary throttle position sensor.

FIG. 5 is a sectional view of a rotor of the sensor.

FIG. 6 is a top view of the rotor.

[Explanation of symbols]

 20 Case 21 Guide part 22 Connector terminal 23 Connector part 24 Flange 25 Mounting hole 26 Mounting part 27 Step part 28 Resin film 29 Resistance pattern 30 Connection part 31 Resistor 32 Presser spring 33 Rotor 34 Projection part 35 Brush 36 Rotation stop part 37 Fitting Joint hole 38 Center hole of perfect circle 39 Thin portion 40 Flat portion 41 Rotating throttle shaft 42 Cover 43 Opening 44 Throttle body

Claims (2)

[Claims] 1. A bottomed tubular case is provided with a resistor on an inner peripheral wall thereof, and a connector terminal connected to an end of the resistor is provided. A rotor having a brush that touches and slides is arranged, and a cover having an opening through which a rotary throttle shaft fitted and coupled to the rotor is inserted is attached to the center of the opening surface of the case.
The rotor has a cylindrical shape and has a fitting hole having a rotation stopping portion which partially forms a flat surface from the insertion opening side of the rotation throttle shaft to a lower middle portion, and the rotation throttle shaft is provided on both sides of the rotation stopping portion. A rotary throttle position sensor provided with a thin portion that absorbs the dimensional difference between 2. The rotary throttle position sensor according to claim 1, wherein a guide portion for guiding a lower end portion of the rotor is provided on an inner bottom portion of the case.