JPH06221944A - Pressure detector - Google Patents

Abstract

PURPOSE:To provide a pressure detector which enable the reducing of the number of parts while facilitating assembling work of parts. CONSTITUTION:A pressure detector slides an energization brush 10 contacting a resistor layer 9 according to the movement of a diaphragm 2 subject to a fluid pressure. A working member 4 is arranged on the diaphragm 2. A torsion coil spring 7 has an intermediate part on the side of a free end thereof abutting the tip part of the working member 4 and the final end thereof is arranged securely on a fixed part. An energization brush 10 is mounted at a free end 7c of the twisting coil spring 7.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pressure detecting device which is applied to a hydraulic pressure detector or the like for detecting the hydraulic pressure of an internal combustion engine or the like and which outputs an electric signal according to the fluid pressure.

[0002]

2. Description of the Related Art For example, as a hydraulic pressure detecting device for an internal combustion engine, conventionally, a diaphragm is arranged at a position where a hydraulic pressure is introduced and applied, and an operating member that moves up and down similarly to the diaphragm is provided on the diaphragm. There is known a pressure detecting device in which a rotating member that rotates in contact with or in connection with is pivotally supported, and an energizing brush that moves in contact with a resistor layer is attached to the tip of the rotating member. (For example, the actual Kaisho 62-7
1539, etc.).

[0003]

However, in this type of pressure detecting device, it is necessary to connect the tension coil spring for returning to the rotating member that rotates in response to the movement of the diaphragm, which leads to a reduction in size. There is a problem that it is very complicated and difficult to mount the tension coil spring in the device which is formed into a very small size according to requirements, and the number of parts is increased.

The present invention has been made in view of the above points, and an object of the present invention is to provide a pressure detecting device which can reduce the number of parts and can easily perform an assembling work of parts.

[0005]

In order to achieve the above object, the pressure detecting device of the present invention detects pressure by sliding a current-carrying brush in contact with a resistor layer in accordance with the movement of a diaphragm which receives fluid pressure. In the device, the actuating member is arranged on the diaphragm, and the torsion coil spring is arranged such that the intermediate portion on the free end side of the torsion coil spring abuts on the distal end portion of the actuating member and the end thereof is fixed to the fixing portion. It is characterized in that a current-carrying brush is attached to the free end.

[0006]

In the pressure detecting device constructed as above, the fluid pressure is applied to the diaphragm, and the diaphragm bends,
When the actuating member moves up and down, the free end side of the torsion coil spring with which the tip of the actuating member abuts swings accordingly. Therefore, the current-carrying brush attached to the free end of the torsion coil spring moves in contact with the resistor layer, the current-carrying brush moves according to the amount of deflection of the diaphragm, and the resistance value changes. The pressure value of the applied fluid pressure is output as an electric signal.

[0007]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a vertical sectional view of a hydraulic pressure detector to which the pressure detecting device of the present invention is applied. Reference numeral 1 is a mounting portion which is mounted on a mounting portion of an internal combustion engine or the like, and a pressure introducing hole 1a is formed in the center thereof.
And is formed of metal. The diaphragm 2 is attached to the upper portion of the attachment portion 1, and the diaphragm 2 is stretched so as to close the internal space of the attachment portion 1 from above.

Further, a cylindrical metal case 3 is fixed on the mounting portion 1 so as to press the peripheral edge portion of the diaphragm 2, and the upper edge portion of the mounting portion 1 is caulked inward to form a case. 3 is attached. Reference numeral 4 denotes an actuating member made of synthetic resin, which is placed on the diaphragm 2 in the case 3, and a rod portion 4a is projectingly provided on the upper portion thereof.

A small diameter portion 4b is formed on the outer peripheral portion of the operating member 4 via a step portion, and a coil spring 5 is externally fitted to the small diameter portion 4b in the case 3, and a substrate 11 is placed on the coil spring 5.
A holder 8 for holding the is provided. Holder 8
Is provided in the center of the bottom of the rod member 4a of the operating member 4.
Is inserted into the hole.

The holder 8 is formed of a synthetic resin in a cylindrical shape, and is inserted from above so as to press the coil spring 5 to a fixed position in the case 3. In that state, the operating member 4 is pressed by a predetermined small load to set. To be done. A substrate 11 having a resistor layer 9 formed on its surface is vertically mounted in the holder 8.

A connector portion 12 made of synthetic resin is arranged on the holder 8 so as to close the upper portion of the case 3,
It is fixed by caulking the top of the case. The connector portion 12 is provided with a plurality of terminals 14 and 15, and the conductive connection portions 16 and 17 of these terminals are provided so as to project to the bottom thereof. The terminal 14 and the resistor layer 9 on the substrate 11 are connected via the conductive connecting portion 16. On the other hand, the conductive connection portion 1
The end 7a of the torsion coil spring 7 is directly fixed to the coil 7 by welding or the like.

The torsion coil spring 7 is arranged along the plane of the substrate 11 in the holder 8, and the intermediate portion of the free end 7c side through the winding portion 7b of the actuating member 4 which is inserted from below is provided. The tip of the rod portion 4a abuts. The energizing brush 10 is attached to the tip of the free end 7c of the torsion coil spring 7 toward the substrate 11, and the tip of the energizing brush 10 contacts the surface of the resistor layer 9. The torsion coil spring 7 is in a state in which its free end 7c side is pressed against the rod portion 4a of the lower operating member 4 by its torsional elastic force.

In the pressure detecting device having the above structure, the torsion coil spring 7 is used as both the return spring and the rotating member.
As in the prior art, complicated and detailed work such as pivotally supporting the rotating member and hooking a small coil spring on the rotating member is unnecessary, and the number of parts can be reduced. Also,
Since the torsion coil spring 7 is used as the current-carrying member, the number of current-carrying brushes and the number of resistor layers can be reduced to one, and the manufacturing cost can be further reduced.

Such a pressure detecting device is attached to a position for detecting the hydraulic pressure of an internal combustion engine or the like, and its connector portion 12 is provided.
The terminals 14 and 15 are connected to a detection circuit (not shown).

When the hydraulic pressure rises and a pressure is applied to the inside of the mounting portion 1 of the pressure detecting device, the diaphragm 2 bends upward and the operating member 4 rises. Rod part 4 of actuating member 4
By the rise of a, the free end 7c side of the torsion coil spring 7 is pushed up, and the current-carrying brush 10 attached to the tip thereof slides on the resistor layer 9 of the substrate 11 to move the operating member 4 up and down. Accordingly, the electric resistance value between the terminals 14 and 15 changes, the voltage value between them changes, and the detection signal is output.

In the above embodiment, the torsion coil spring 7 is used.
Was used as a current-carrying member, but two current-carrying brushes were short-circuited, and one resistor layer or conductor layer was added on the board.
If you configure the energizing brush to slide on each,
The torsion coil spring 7 may be a non-conductive member.

[0018]

As described above, according to the pressure detecting device of the present invention, in the pressure detecting device for sliding the energizing brush in contact with the resistor layer in accordance with the movement of the diaphragm receiving the fluid pressure, the diaphragm The actuating member is arranged on the upper side, and the torsion coil spring is arranged such that the middle portion of the torsion coil spring abuts on the tip end of the actuating member and one end of the torsion coil spring is fixed to the fixed portion. Because I configured
Since the torsion coil spring is used as both the return spring and the rotating member, the complicated and detailed work such as pivotally supporting the rotating member and hooking a small coil spring on the rotating member is required as in the conventional case. It becomes unnecessary and the number of parts can be reduced. Further, if the torsion coil spring is used as the current-carrying member, the number of current-carrying brushes and the number of resistor layers can be reduced to one, and the manufacturing cost can be further reduced.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view of a pressure detection device showing an embodiment of the present invention.

FIG. 2 is a sectional view taken along the line II-II in FIG.

[Explanation of symbols]

 2-diaphragm, 4-actuating member, 7-torsion coil spring, 9-resistor layer, 10-current-carrying brush, 11-substrate.

Claims (2)

[Claims] 1. A pressure detecting device for sliding a current-carrying brush in contact with a resistor layer in response to a movement of a diaphragm receiving fluid pressure, wherein an operating member is disposed on the diaphragm, and a torsion coil spring is free. The end portion side intermediate portion is disposed in contact with the tip end portion of the actuating member and the end thereof is fixed to the fixed portion, and the energizing brush is attached to the tip end of the free end of the torsion coil spring. Pressure detection device. 2. The pressure detecting device according to claim 1, wherein an end of the torsion coil spring is directly fixed to a conductive connecting portion, and the torsion coil spring is used as a current-carrying member.