JPH0136101Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a pressure detection device using a diaphragm.

One type of conventional pressure detector of this type is shown in FIG. That is, a metal diaphragm 4 having an annular unevenness in the diametrical direction and provided with a rubber seal 2 on the peripheral edge of the lower surface is interposed between the lower casing 1 and the pedestal 7. A ring-shaped spacer 14 is formed between the diaphragm 4 and the pedestal 7, and a ring-shaped spacer 14 shown in FIG. A circular plate spring 6 having a spring piece 6' as shown in FIG. 2 in contact with is interposed. Note that the hardness of the material of the diaphragm 4 is set lower than that of the spacer 14. 8 is an operating punch that comes into contact with the center of the upper surface of the diaphragm 4;
This operating punch 8 is connected to a link mechanism 9 mounted on the pedestal 7, and by the vertical movement of this operating punch 8,
A movable contact 11 of a variable resistor 10 is configured to slide on a resistance pattern 13 surface on a resistance plate 12. Incidentally, the peripheral edges of the lower casing 1 and the pedestal 7 are attached to the lower part of the upper casing 3 by a caulking part formed at the lower part thereof. Therefore, when pressure is supplied from the pressure supply port 1' of the lower casing 1, the pressure inside the pressure receiving chamber 5 increases,
Since the diaphragm 4 is pushed up, the link mechanism 9 and the movable contact 11 operate, and pressure is electrically detected based on a change in resistance value.

However, in such a conventional pressure detection device, when the diaphragm 4 is pushed up as shown in FIG.
Corner 1 of the inner peripheral edge of the spacer 14 as shown by the solid line
4a, when the diaphragm 4 returns to its original position, its flat part moves as shown by the broken line.
Since the corner portion 14a of the spacer 14, that is, the structure is such that it returns to its original position by friction while abutting against the inner peripheral edge, the flat portion 4a of the peripheral edge of the diaphragm 4 is abraded by the corner portion 14a of the spacer 14. , there are problems such as a decrease in the mechanical strength of that part and a tendency for cracks to form.

The present invention was developed by focusing on such conventional problems, and the inner peripheral edge of the spacer is positioned in the recess formed in the diaphragm, so that the diaphragm is protected by the peripheral edge of the spacer. It is an object of the present invention to provide a pressure detection device that can prevent damage.

The present invention will be explained in detail below based on the embodiment shown in FIG. A description of the structure will be omitted.

That is, the spacer 14' in this embodiment is formed so that its radial width r is larger than the width of the spacer 14 shown in the conventional example, and its inner peripheral edge 14'a
is an annular recess 4 formed in the diaphragm 4.
By setting the diaphragm 4 to be positioned above b, when the diaphragm 4 moves up and down according to the pressure within the pressure receiving chamber 5, the diaphragm 4 comes into contact with the inner peripheral edge 14'a of the spacer 14'. Since there is no
The diaphragm 4 is not worn or damaged due to contact with the spacer 14', and a durable pressure detection device can be provided.

As described above, the present invention provides a pressure receiving chamber 5 on one side of the diaphragm 4 having a plurality of annular irregularities concentrically, and a signal on the other side corresponding to the displacement of the diaphragm 4 due to pressure changes in the pressure receiving chamber. A displacement transducer 10 is provided, and a plate spring 6 for making the output characteristics of the displacement transducer non-linear is spaced apart from the diaphragm 4 by a ring-shaped spacer 14' at a predetermined interval. This pressure detecting device is characterized in that the inner circumferential edge 14'a of the spacer 14' is positioned corresponding to the annular recess formed in the diaphragm 4. According to this pressure detecting device, , since the inner circumferential edge of the spacer does not come into contact with the moving part of the diaphragm when the diaphragm is displaced, the diaphragm 4 is moved around the edge 14'a of the spacer.
This has the effect of providing a durable pressure detection device that does not suffer from wear and tear due to contact with the pressure sensor.

[Brief explanation of the drawing]

Fig. 1 is a sectional view showing a conventional pressure detection device, Fig. 2 is a plan view of only the leaf spring, Fig. 3 is a plan view of only the spacer, and Fig. 4 is an explanatory diagram showing the operation of the diaphragm. , FIG. 5 is a sectional view showing an embodiment of the pressure detection device according to the present invention. 14'...Spacer, 14'a...Inner peripheral edge, 4
...Diaphragm.

Claims (1)

[Scope of utility model registration request] A pressure receiving chamber 5 is provided on one side of a diaphragm 4 having a plurality of annular irregularities concentrically, and a displacement converter 10 is provided on the other side for emitting a signal in accordance with the displacement of the diaphragm 4 due to pressure changes in the pressure receiving chamber. With,
In a pressure sensing device, a plate spring 6 for making the output characteristics of the displacement transducer non-linear is spaced at a predetermined distance from the diaphragm 4 by a ring-shaped spacer 14'. A pressure detection device characterized in that a peripheral edge 14'a is positioned corresponding to an annular recess formed in the diaphragm 4.