JPS61138423A - 3-action type pressure switch - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a so-called three-operation type pressure switch that operates at low pressure, medium pressure, and high pressure, which is used, for example, in a safety control system for a car cooler.

(Prior art) Conventionally, as a combination type or three-action type pressure switch, there are disclosed Utility Model Application Publications No. 58-13642 and Utility Model Application No. 58-169.
The ones disclosed in Japanese Unexamined Patent Publication No. 636 or Japanese Utility Model Application Publication No. 59-82936 are known.

However, in the pressure switches disclosed in these publications, (a) the microswitch is made to perform a snap action operation, so there is a possibility that chattering may occur at the contacts.口) The contact plate may be deformed more than necessary due to the overstroke after the reversal plate is reversed, and the durability of the contact plate and contacts may be impaired. c) Some of the terminals may move during operation, resulting in poor characteristics in long and simple applications. 2) Problems have been pointed out in the case where two reversing plate holders are used, such as the shape becomes large, and it cannot be said that the result is necessarily satisfactory.

(Problems to be Solved by the Invention) The present invention has been made by focusing on the above-mentioned problems of the conventional composite pressure switch.
Even when a switch that utilizes the reversal of the reversing plate is operated, no excessive overstroke occurs on the contact plate, resulting in excellent durability.In particular, the structure of the reversing plate holder has been streamlined to make the entire switch compact. The purpose of the present invention is to provide a three-action pressure switch.

(Means for Solving the Problems) The present invention will be explained below based on the attached drawings showing embodiments.

A is a switch body, and a joint B having a pressure introduction hole 1 is fixed to the lower surface of the switch body through a seal ring 2 made of rubber or the like, and a seal made of polyimide or the like is placed between the peripheral edge of the switch body A and the joint B. A diaphragm 3 made of resin is clamped at its periphery.

The inside of the switch body A is substantially divided into a pressure receiving chamber A1 on the side of the joint B and a contact chamber A2 located above the pressure receiving chamber A1 via a reversing plate pusher 4. A reversing plate holder 5 is provided in the pressure receiving chamber A1 so as to be slidable within the receiving chamber A+ by a certain distance with respect to the reversing plate pusher 4. A pressure reversing plate 6 is reversibly held in contact with the diaphragm 3 by a concave end surface 5a formed on the diaphragm 3 side of the reversing plate receiver 5, and the pressure reversing plate 6 is held on the pressure introduction hole 1 side of the joint B except during high pressure operation. The bulge is inverted.

Further, an annular groove 5c is formed in the reversing plate receiver 5 from a concave end surface 5b formed on the reversing plate pushing tool 4 side of the reversing plate receiver 5, and a spring 7 is loosely inserted into the groove 5C. Further groove 5
The reversing plate 8 is held between the end surface of the spring 7 protruding from 0 and the reversing plate pushing tool 4, and the reversing plate pushing tool 4 is pushed by the spring 7 to the inner wall step Aa of the switch body A via the reversing plate 8. It is assigned.

Further, the reversing plate 8 is formed to be reversible using a protrusion 4a formed on the surface of the reversing plate pusher 4 that corresponds approximately to the spring 7 as a support point, and when operated under low pressure, the reversing plate 8 bulges toward the reversing plate presser 4 side. The part is reversed.

Further, a protrusion 5e is formed in the contact chamber A2 from the center of the end surface 5b of the reversal plate holder 5 through the central hole of the reversal plate 8 and the reversal plate pusher 4. A cylindrical rod 9 is loosely fitted onto the upper surface of the cylindrical rod 8, leaving the upper part of the protrusion 5e.

Further, a shaft hole 5f is provided through the center of the reversing plate receiver 5 including the protruding portion 5e, and a long rod 10 is loosely inserted into the shaft hole 5f. The lower end of this long rod 10 is in contact with the pressure reversal plate 6, and the upper end is in contact with the protrusion 5.
It further protrudes from the upper end of e.

Next, in the contact chamber A2, a switch S1 and a switch S2, which move toward and away from the fixed contact 11a in conjunction with the cylindrical rod 9, and a switch S2, which moves toward and away from the long rod 10 and the protrusion 5e of the reversing plate holder 5.
is accommodated.

Switch S1 has terminal 1 crimped and fixed to switch body A.
1, a terminal 12 crimped to the switch body A, and a movable contact 12a provided to the free end of a contact plate 12b crimped to the other end of the terminal 12. The movable contact 12a is connected to the fixed contact 1 by the middle part of the contact plate 12b coming into contact with and separating from the upper surface of the cylindrical rod 9.
It is configured to be in contact with and separate from 1a.

Further, the switch S2 has a terminal 13 crimped and fixed to the switch body A and a contact plate 13 crimped to the other end of the terminal 13.
A movable contact 13a provided at the free end of b, a terminal 14 swaged to the switch body A, and a movable contact 14a provided at the free end of the contact plate 14b swaged to the other end of the terminal 14. The contact plate 14b is held in a fixed position by a stopper 15 connected to the base plate of the terminal 14 against elasticity in the mounting direction.

On the other hand, the middle part of the contact plate 13b is always in elastic contact with the upper surface 5g of the protruding part 5e, and the movable contact 13a is in contact with the upper surface 5g of the protruding part 5e.
The movable contact 14a is configured to come into contact with and separate from the movable contact 14a in response to the vertical movement of the pressure reversing plate 6, and the movable contact 14a comes into contact with and leaves the movable contact 13a when the long rod 10 comes into contact with and leaves the contact plate 14b as the pressure reversal plate 6 is reversed. Ru.

(Function) Next, the operation of the three-action pressure switch of the present invention having the above structure will be explained based on FIGS. 1 to 4.

FIG. 1 shows the operating state when the internal pressure of the pressure introduction hole 1 of the joint B is Okg/cJ, and the switches S] and S2 are both in the open state.

From this state, (as shown in FIG. 2, when the internal pressure of the Al pressure introduction hole 1 becomes a low working pressure, the reversing plate receiver 5, together with the pressure reversing plate 6, resists the biasing pressure of the spring 7 due to the pressure acting on the diaphragm 3. and slides upward, and the contact plate 13b of the switch S2 is pushed by the upper surface 5g of the protrusion 5e.
Contact 13a and contact 14.2 come into contact and switch S2 is closed. In this state, the reversing plate 8 contacts the end surface 5b of the reversing plate receiver 5 at its end edge. In addition, in this low-pressure operating state, the contact plate 12b of the switch S1 is held by the cylinder rod 9, and the switch S1 is open.

QII) Next, when the inside of the pressure introduction hole 1 rises from the low working pressure of (al) to the medium working pressure, the reversing plate 8
is pushed by the reversing plate receiver 5 at its end edge, and its bulging portion is reversed using the projection 4a of the reversing plate pusher 4 as a support point. Then, the cylindrical rod 9 moves downward as the reversing plate 8 is reversed, and the contact plate 12b, which was held against the upper surface of the cylindrical rod 9 against elasticity, separates from the upper surface of the cylindrical rod 9, and the contact 12a becomes a fixed contact. 1
1a, and the switch S1 is also closed. In this state, the upper edge 5d of the reversing plate holder 5 is pressed against the reversing plate pushing tool 4.
be in contact with Note that when the medium-pressure operating state shown in FIG. 3 returns to the low-pressure operating state, the reversing plate 8 is reversed by the spring force of the reversing plate 8, and the switch S1 is opened as shown in FIG. 2.

(C) Next, when the internal pressure of the pressure introduction hole 1 rises from the medium working pressure to the high working pressure in (b), the bulge of the pressure reversing plate 6 is reversed as shown in FIG. Push the long rod 10 that is in contact with 6 upward. Then, the upper end of the long rod 10 pushes up the contact plate 14b to separate the contact 14a from the contact 13a, opening the switch S2. In this state, the bulging portion of the pressure reversal plate 6 contacts the center portion of the lower end surface 5a of the reversal plate receiver 5. Note that when the high pressure operating state shown in FIG. 4 returns to the intermediate pressure operating state, the pressure reversing plate 6 is reversed and the contact 13a is
, 14a are in contact, and the switch S2 is in the closed state as shown in FIG.

(Application Example) Next, an application example will be described in which the pressure gas isolator of the present invention is used, for example, in a car cooler safety control system.

That is, the joint B of the pressure switch of the present invention is connected to the high-pressure gas side pressure introduction hole of the car cooler, and the switch S2 of the pressure switch is connected to the compressor circuit of the car cooler as shown in FIG. Furthermore, if a switch S1 is connected to the fan motor circuit for cooling the condenser, when the gas pressure flowing through the compressor becomes 0 due to a gas leak, the switch S2 will be opened as shown in Figure 1, and the high pressure side of the car cooler will be opened. If the gas pressure in the piping rises to abnormally high pressure,
The high pressure operates in the direction of the arrow in FIG. 5, and the switch S2 opens as shown in FIG. 4 to disconnect the magnetic clutch of the compressor circuit, thereby preventing danger.

In addition, when the gas pressure in the high-pressure side pipe of the car cooler exceeds a predetermined pressure, it operates in the direction of the intermediate pressure arrow in Figure 5, and the switch S1 closes as shown in Figure 3, causing the condenser cooling Fan motor operates. On the other hand, when the gas pressure in the high-pressure side piping of the car cooler falls below a predetermined pressure, the switch S1 in FIG. 5 is opened to stop the fan motor and control the operation to a normal state.

(Effects of the Invention) The pressure switch of the present invention has the configuration and operation described in detail above, and has two sets of switches for low pressure, medium pressure, and high pressure.
Since the structure is such that two reversing plates for operation are placed on both ends of one reversing plate holder, the entire switch can be integrated into a compact unit, and the reversing plate is used for the actuating part of the switch. Since it uses a snap action, there is no chattering at the contact points. moreover,
Both the medium-pressure operating switch S1 and the low- and high-pressure operating switches S2 are formed in a structure that does not cause excessive overstroke on the contact plate, so the durability of the contact plate and contacts is significantly improved. Benefits can be obtained.

[Brief explanation of drawings]

Figures 1 to 4 are longitudinal cross-sectional views of the three-operation type pressure switch of the present invention, where Figure 1 shows the operating state at internal pressure Okg/csl, Figure 2 shows the state after low pressure operation, and Figure 3 shows the state at medium pressure. Figure 4 shows the state after high pressure operation. FIG. 5 shows an operational block diagram when the pressure cage inch of the present invention is applied to a car cooler. A...Switch body, B...Joint, 1...Pressure introduction hole, 3...Diaphragm, 4...Reversing plate pusher,
5... Reversing plate holder, 6... Pressure reversing plate, 7... Spring, 8... Inverting plate, 9... Cylindrical rod, 10...
Long rod, 11, 12, 13.14...terminal, Ila, 1
2a, 13a, 14a... Contact, 12b, 13b, 1
4b... Contact plate, 15... Stopper.

Claims (1)

[Claims] A diaphragm is narrowly attached between the switch body and a joint having a pressure introduction hole, the inside of the switch body is almost divided into a pressure receiving chamber and a contact chamber by a reversing plate pusher, and a reversing plate holder is inserted into the pressure receiving chamber by the reversing plate. A pressure reversing plate is provided on the end face of the reversing plate on the diaphragm side, and a spring is loosely inserted into the reversing plate receptacle from the end face of the reversing plate on the pushing tool side. A reversing plate is provided between each of the reversing plate pushers, and a long rod that interlocks with the reversal of the pressure reversing plate is inserted into the shaft hole of the reversing plate holder, and further protrudes from the end surface of the reversing plate holder into the contact chamber. A cylindrical rod that is interlocked with the reversal of the reversing plate is inserted into the protrusion, and a switch that moves toward and away from the fixed contact in conjunction with the cylindrical rod is inserted into the contact chamber, and a switch that is interlocked with the long rod and the protrusion. A three-action pressure switch characterized by having a switch that connects and disconnects.