JPH0521809Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention relates to a pressure switch, and in particular, an object of the invention is to provide a pressure switch that can improve durability.

[Prior art and problems to be solved]

Generally, for pressure switches, the fifth
It is constructed as shown in FIGS.

That is, the device has an inlet case 22 having a pressure inlet 21 on the underside thereof, which is connected to a hydraulic line, and a main body case 23 located above the inlet case 22, the lower part of which is fitted into the upper part of the inlet case 22 to form an integrated unit. A diaphragm 24 is located inside the inlet case 22, and the diaphragm 24 is connected to the main body case 23.
A cylinder 25 is disposed between the upper surface of the main body case 23 and the upper surface of the main body case 23.
A piston 26 is disposed inside the main body case 23 in a hole 23a at the closed lower end thereof so as to be movable up and down.

The upper surface of the piston 26 contacts the lower surface of the connecting rod 29, which is biased downward by a spring 28 whose biasing force is stored by a stopper 27 inside the main body case 23, and The diaphragm 24 is disposed such that its lower surface is located within a recess 24a provided on the upper surface of the diaphragm 24.

The connecting rod 29 has a lower part with a larger diameter, an upper part that can slide inside a hole 27a provided in the center of the stopper 27, and an upper surface that is arranged inside the main body case 23. It is in contact with the actuating part 31 of the micro switch 30 disposed at the top.

In the conventional pressure switch configured as described above, when pressure fluid is introduced into the pressure introduction port 21, this pressure is transmitted to the diaphragm 24, which allows it to slide inside the cylinder 25. The piston 26 is slid upward and the connecting rod 29 is connected to the spring 28 via the piston 26.
The upper surface of the connecting rod 29 presses the operating portion 31 of the micro switch 30 to operate the micro switch 30.

Therefore, it is essential that the piston 26 is slidably disposed within the hole 25a of the cylinder 25, and for this purpose, as shown in FIGS. A gap B is provided between the piston 26 and the piston 26.

For this reason, the part A of the diaphragm 24 that is under pressure enters the gap B and is pinched, resulting in a problem that the diaphragm 24 is damaged in a short period of time.

The time it takes for this damage to occur is determined by the fact that the higher the pressure introduced into the pressure introduction port 21, the deeper the position A of the diaphragm 24 goes into the gap B. The effects of this are significant, requiring control of high dimensional accuracy during processing, making control during processing difficult.

For this reason, in the past, for example, the operating pressure
If the pressure exceeds 100 kgf/ ^cm2 , the material cannot be used as is.

This idea solves the above-mentioned problems of the conventional ones, and allows the diaphragm to separate from the cylinder and piston when high pressure is applied, without increasing dimensional control when manufacturing the cylinder and piston. To provide a pressure switch which can prevent damage to a diaphragm and thereby improve overall durability.

[Means to solve the problem]

In order to achieve the above problems, this invention disposes a connecting rod for operating the switch in a downwardly biased state inside the main body case, which has a hole bored in the closed lower end. , a piston whose upper surface abuts the connecting rod is disposed in the hole of the main body case, a cylinder and a resin ring having an annular hanging portion are sequentially inserted into the piston, and the lower surface of the piston is inserted into the piston. In addition to disposing a diaphragm that comes into contact with the body case, an inlet case having a pressure introduction hole is disposed in the main body case so that when fluid is introduced into the pressure introduction hole, the pressure of the fluid flows through the diaphragm. A means is adopted in which the hanging portion of the resin ring is pressed to bring it into close contact with the piston.

[Effect]

By adopting the above-mentioned means, this idea
When pressure fluid is introduced and the piston slides in the bore of the cylinder via the diaphragm, the resin ring reliably prevents a part of the diaphragm from entering between the cylinder and the piston. Become.

〔Example〕

Embodiments of this invention shown in the drawings will be explained below. FIGS. 1 to 4 show a pressure switch according to this invention, and like the conventional one, the pressure switch is connected to a hydraulic line. It has an inlet case 2 with an inlet 1 provided on the lower surface, and a main body case 3 located above the inlet case 2 and whose lower part fits into the upper part of the inlet case 2 and is integrated with the inlet case 2. A diaphragm 4 is located inside, and a cylinder 5 is disposed between the upper surface of the diaphragm 4 and the main body case 3. Inside the hole 5a of the cylinder 5, the main body case 3 A piston 6 provided inside the hole 3a at the closed lower end is arranged to be movable up and down.

The upper surface of the piston 6 abuts against the lower surface of the connecting rod 9 which is biased downward by a spring 8 whose biasing force is stored by a stopper 7 inside the main body case 3; Further, a recess 4 whose lower surface is provided on the upper surface of the diaphragm 4
It is placed inside a.

Furthermore, a step groove 4b concentric with the recess 4a is formed on the upper surface of the diaphragm 4, and a center hole 1 is formed in the step groove 4b to form an annular shape.
A flexible resin ring 12 with an annular hanging portion 12b integrally formed on the lower edge of the resin ring 2a is disposed, and the lower end of the piston 6 is located inside the center hole 12a of the resin ring 12. insert, and
The lower end is located within the recess 4a of the diaphragm 4.

Further, the connecting rod 9 has a lower part with a large diameter, an upper part that can slide in a hole 7a provided in the center of the stopper 7, and an upper surface that is connected to the main body case 3. The actuating portion 11 of the micro switch 10 is disposed in the upper part of the inside of the switch.

Next, the operation of the above will be explained.

First, when pressure fluid is introduced into the pressure introduction port 1, this pressure is transmitted to the diaphragm 4 and moves the piston 6 slidably disposed in the hole 5a of the cylinder 5 upward. The connecting rod 9 is raised through the piston 6 against the biasing force of the spring 8, and the upper surface of the connecting rod 9 presses the actuating portion 11 of the micro switch 10 to operate the micro switch 10. I'm starting to let them do it.

During the above operation, when fluid is introduced into the pressure introduction port 1, the diaphragm 4 is displaced by the pressure and presses the cylinder 5 and the piston 6 with substantially the same pressure.

A resin ring 12 is disposed within the step groove 4b of the diaphragm 4, and a hanging portion 12b is formed in a portion of the resin ring 12 surrounding the piston 6, so that the pressure fluid is transferred to the diaphragm 4. When pressed, the diaphragm 4 presses the resin ring 12 and presses it against the cylinder 5 and piston 6. In particular, the resin ring 1
Since the hanging part 12b provided on the cylinder 2 is easily deformable, its upper surface is pressed against the cylinder 5, and
The hanging portion 12b is deformed and pressed against the piston 6.

Therefore, even when the piston 6 slides in the hole 5a of the cylinder 5 and moves up and down in response to fluctuations in the introduced pressure, the hanging portion 1 of the resin ring 12
2b comes into close contact with the piston 6, and as a result, the gap between the hole 5a of the cylinder 5 and the piston 6 is
It is possible to reliably prevent a portion of the diaphragm 4 from getting into the gap B and causing damage.

[Effect of idea]

By configuring this idea as described above,
During operation when pressure fluid is introduced, it is possible to reliably prevent a part of the diaphragm from getting caught between the cylinder and the piston, thereby significantly improving durability. This can be achieved without increasing processing accuracy, making manufacturing management easy and
This has excellent effects such as being able to reduce the overall cost.

[Brief explanation of the drawing]

Figures 1 to 4 show the pressure switch according to this invention, with Figure 1 being a schematic cross-sectional view of the whole, Figure 2 being an enlarged view showing the relationship between the cylinder, piston, resin ring, and diaphragm, and Figure 3 is a schematic diagram showing the disassembled state of the one in Figure 2, Figure 4 is a schematic diagram showing the main parts, Figures 5 to 8 show a conventional pressure switch, and Figure 5 is an overall schematic diagram. 6 is an enlarged view showing the relationship between the cylinder, piston, and diaphragm, FIG. 7 is a schematic diagram showing the exploded state of the one in FIG. 6, and FIG. 8 is a schematic diagram showing the main parts. . 1, 21... Pressure introduction port, 2, 22... Inlet case, 3, 23... Main body case, 4, 24... Diaphragm, 4a, 24a... Recess, 4b... Step groove, 5, 25... Cylinder, 3a, 5a, 7a,
23a, 25a, 27a... Hole, 7, 27... Stopper, 8, 28... Spring, 9, 29... Connecting rod, 10, 30... Micro switch, 11, 31... Operating part, 12 ...resin ring, 12a...center hole, 12b...hanging part, A...
...Part of the diaphragm, between B...〓.

Claims (1)

[Scope of utility model registration request] The switch 1 is inserted into the main body case 3, which has a hole 3a formed in the closed lower end, in a downwardly biased state.
A connecting rod 9 for the operation of 0 is arranged,
A piston 6 whose upper surface abuts the connecting rod 9 is disposed in the hole 3a of the main body case 3, and a cylinder 5 and a resin ring 12 having an annular hanging portion 12b are sequentially attached to the piston 6. A diaphragm 4 is inserted through the main body case 3 and comes into contact with the lower surface thereof, and an inlet case 2 having a pressure introduction hole 1 is disposed in the main body case 3 so as to be integrated.
When fluid is introduced into the pressure introduction hole 1, the pressure of the fluid causes the resin ring 1 to flow through the diaphragm 4.
2. A pressure switch characterized in that a hanging portion 12a of the pressure switch 2 is pressed and comes into close contact with the piston 6.