seat switch device

Abstract

A seating switch device is a switch mechanism comprising a magnet (23) and a reed contact switch (24), wherein the magnet performs switching operation through deformation of a diaphragm 20. The switch mechanism enables the magnet (23) to be fixed to the diaphragm (20) facing one side of a pressure chamber (21). The reed contact switch (24) keeps parallel to or substantially parallel to the magnet (23) along the length to be opposite to the magnet. The relative space between the magnet (23) and the reed contact switch (24) is changed on the basis of deformation of the diaphragm (20), so that the switch mechanism can perform switching operation.

Description

technical field [0001] The invention relates to a seat switch device for detecting the pressure difference of a pair of pressure chambers divided by membrane components such as diaphragms. Background technique [0002] As such a switch device, the structure described in Patent Document 1 is conventionally known, and in Figure 4 The outline of this conventional switchgear is shown in . [0003] Figure 4 In the shown conventional switching device, a diaphragm 2 is provided in a housing 1 , which divides the interior of the housing 1 into a pair of pressure chambers 3 , 4 . The diaphragm 2 is provided with folds 2 a on its outer side so as to be deformable according to the pressure difference between the pressure chambers 3 and 4 . [0004] In addition, reference numeral 5 in the figure is a pressure introduction port for introducing pressure into one pressure chamber 3 , and 6 is a pressure introduction port for introducing pressure into another pressure chamber 4 . [000...

AI Technical Summary

Problems solved by technology

[0015] First, if the pleats 2a are large, the response of the diaphragm 2 to repeated deformation becomes poor, and the diaphragm 2 cannot be deformed sufficiently with a small pressure.

[0016] In addition, in order to enlarge the pleats 2a, it is necessary to increase the thickness of the convoluted portion 2a, but the increase in thickness inevitably impairs the ease of deformation, and the response when repeated deformations in the above-mentioned manner deteriorates.

[0017] For this reason, in the conventional switchgear in which the pleated portion 2a must be enlarged, there is a problem that the pressure difference detection sensitivity is not high.

[0018] In addition, although the seat switch device of the present invention requires high-precision pressure difference detection, sufficient accuracy is not required in the above-mentioned conventional switch device, so there is a problem that it cannot be used as a seat switch device.

[0019] In addition, if the thickness of the pleats 2a is increased as described above, the pressure difference operating pressure will also increase, and if the pressure difference operating pressure increases, for example, when the ambient temperature changes, the detection error will also increase.

This is because, when the temperature changes, the elastic coefficient of the diaphragm will change, and the operating pressure of the pressure difference will also change. Big

[0020] In addition, the fluid pressure from the supply source is not necessarily constant. If the sensitivity of the pressure difference detection is poor as described above during its large variation, the distance between the detection nozzle and the object close to it is taken as one axis, In a two-dimensional graph that uses the pressure difference between the two pressure chambers as the other axis, the gain of the characteristic curve will change significantly due to changes in the supply pressure

If the gain of the characteristic curve is changed, there will be a problem that the detection accuracy of the pressure difference will be worse

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