CN104752096A - Pressure switch - Google Patents

Abstract

The invention provides a pressure switch, of which the pressure tolerance is enhanced without increase of cost and avoids upsizing with the enhanced pressure tolerance. In a diaphragm assembly of the pressure switch (20), a diaphragm group (20B) of the outer peripheral edge is on the board (20A) and a lower plate (20C) sandwiched, and the diaphragm group (20B) of part of the side, closer to the center than the outer peripheral edge, is supported on the O-ring.

Description

Pressure switch

Technical field

The present invention relates to pressure switch.

Background technology

In aircondition etc., in general, in pipe arrangement, possess the pressure for detecting in pipe arrangement cold-producing medium, carbon dioxide etc. and send the pressure switch detecting and export.As shown in patent documentation 1 and patent documentation 2, pressure switch be configured to comprise the body shell that the one end via junction block is connected with coolant channel, the compression chamber be separated out in body shell diaphragm group, can according to the displacement of diaphragm group make to be configured in travelling contact in body shell and fixed contact close to or far away from action pin.

This diaphragm group is formed as pressure according to coolant channel and multiple diaphragms overlapped.The outer peripheral edges of diaphragm group are clamped between the circumference of body shell and limiting component, to form the compression chamber in body shell.Along with the use pressure of coolant channel becomes high pressure, require the resistance to pressure between the circumference of body shell and limiting component.

Patent documentation 1: Japanese Unexamined Patent Publication 2004-121140 publication

Patent documentation 2: Japanese Unexamined Patent Publication 2002-279875 publication

Summary of the invention

When requiring the resistance to pressure between the circumference of body shell and limiting component, the clamp pressure produced between the circumference of body shell and limiting component should be increased, consider the thickness increasing body shell and limiting component, improve press pressure required when the riveting part as the connecting member circumference of body shell and limiting component linked is riveted simultaneously.Or, as shown in patent documentation 2, propose and make diaphragm keep the canopy face of container structure body to be inclined plane.

But the size that there is pressure switch becomes large and that manufacturing cost increases along with the machining of parts worry.

Consider above problem points, the object of the invention is to, a kind of pressure switch is provided, resistance to pressure and can not manufacturing cost uprises with the machining of parts can be improved, and, the maximization of pressure switch strengthened along with resistance to pressure can be avoided.

In order to realize above-mentioned object, the feature of pressure switch of the present invention is to possess: shell, and it has multiple splicing ears of at least one pair of travelling contact and fixed contact in inner side storage; Diaphragm unit, itself and shell link, and have with supply operating pressure pipeline be connected and produce at least one diaphragm of displacement according to this operating pressure; And opening/closing unit, it makes travelling contact and the fixed contact opening and closing of splicing ear according to the displacement of the diaphragm of diaphragm unit, the peripheral part of the diaphragm of diaphragm unit is fixed, and is supported by the elastomeric element of ring-type than the part of peripheral part closer to the central side of diaphragm.

According to pressure switch of the present invention, the peripheral part of the diaphragm of diaphragm unit is fixed, and supported (part opposed with the periphery of the open end of pipeline is supported by the elastomeric element of ring-type) by the elastomeric element of ring-type than the part of peripheral part closer to the central side of diaphragm, thus the maximum stress of diaphragm can be reduced, so do not increase manufacturing cost just can improve resistance to pressure, further, the maximization of the pressure switch strengthened with resistance to pressure can be avoided.

Accompanying drawing explanation

Fig. 1 is the cutaway view of the major part of the example representing pressure switch of the present invention.

Fig. 2 is the cutaway view of the diaphragm unit used in other example of pressure switch of the present invention.

Fig. 3 (A) and Fig. 3 (B) is the partial sectional view of the action of an example for illustration of past case and pressure switch of the present invention respectively.

Fig. 4 is the bending figure of the diaphragm group for illustration of past case.

Fig. 5 is the bending figure of the diaphragm group used in an example for illustration of pressure switch of the present invention.

Fig. 6 is the performance plot of the change of the flexibility factor represented corresponding to internal diameter radius ratio.

Fig. 7 is the performance plot of the change of the stress coefficient represented corresponding to internal diameter radius ratio.

In figure: 12,14-splicing ear, 12a-fixed contact, 14a-travelling contact, 20,30-diaphragm unit, 20A, 30A-upper plate, 20B, 30B-diaphragm group, 20bi, 30bi-diaphragm, 20C, 30C-lower plate, 24,34-O type ring, 36-support ring.

Embodiment

Fig. 1 represents the major part of an example of pressure switch of the present invention.

Pressure switch is such as installed on the pipe arrangement omitting illustrated hydraulic means or air supply, cold-producing medium, water etc. via jointing 28.

As shown in Figure 1, pressure switch is closed type switch, is configured to comprise as main key element: the diaphragm unit 20 be combined with one end of jointing 28, to link and the housing 10 of built-in a pair splicing ear described later 12 and 14, be configured in housing 10 and make the fixed contact 12a of a pair splicing ear 12 and axle 16P of travelling contact 14a opening and closing of splicing ear 14 and the axle guide member 16 of leading axle 16P according to the displacement of diaphragm group 20B described later with diaphragm unit 20.

Housing 10 as shell is such as shaped by resin material, has the recess of storage as the fixed contact 12a of a pair splicing ear 12 of multiple splicing ear and the movable plate 14b of splicing ear 14 and travelling contact 14a in inner side.The external connecting of splicing ear 12 is externally given prominence to by the slit of housing 10.The external connecting of splicing ear 14 is externally given prominence to by the slit of housing 10 in the mode almost parallel with the external connecting of splicing ear 12.The external connecting of splicing ear 12 and 14 is such as connected with the illustrated control circuit of omission respectively.Thus, as shown in Figure 1, splicing ear 12 and 14, when fixed contact 12a and travelling contact 14a abuts, will represent that the signal of opening supplies to control circuit via external connecting.In addition, splicing ear 12 and 14 when fixed contact 12a and travelling contact 14a mutually away from, will represent that the signal of closed condition is supplied to external connecting.

In addition, in above-mentioned example, splicing ear 12 and 14 is single-pole single-throw formula, but is not limited to this example, such as, also can be the switch forming single-pole double-throw formula, DPST formula, DPDT formula, TPST formula, triple-pole double throw formula.

Axle guide member 16 has axle 16P with can the through hole that inserts of the mode of movement at central portion.The outer peripheral edges of axle guide member 16 are embedded in the open end be communicated with the recess of housing 10.Across be formed at axle guide member 16 outer peripheral edges ring-type groove and be formed at housing 10 open end groove and be configured with O type ring 18.

As shown in Figure 1, the interval of one end by the through hole of axle guide member 16 across regulation of axle 16P is opposed with the jut of the movable plate 14b of splicing ear 14.The other end of axle 16P, is abutted with the substantially central portion of the end face of diaphragm group 20B by the through hole 20a of the upper plate 20A of diaphragm unit 20.Thus, axle 16P one end according to result from the fluid supplied by runner 28a in jointing 28 operating pressure diaphragm group 20B end face substantially central portion displacement and towards the movable plate 14b of splicing ear 14 jut close to or far away from.Therefore, the fixed contact 12a in splicing ear 12 and 14 and travelling contact 14a is opened and closed by the moving of one end of the axle 16P corresponding with the operating pressure supplying the fluid come via the runner 28a in jointing 28.

Diaphragm unit 20 be configured to using the lower plate 20C be connected with one end of jointing 28 with the upper plate 20A that the open end periphery and O type ring 18 of housing 10 abut, be clamped in diaphragm group 20B between mutually opposing upper plate 20A and lower plate 20C and as the O type ring 24 of the elastomeric element of ring-type for staple.

Upper plate 20A by drawing, cut, die casting, forging etc., such as, is shaped by metal material and forms, across the gap of regulation opposite with the end face of axle guide member 16 configure.Upper plate 20A has for the through through hole 20a of the other end of axle 16P at central portion.

Lower plate 20C by drawing, cut, die casting, forging etc., such as, is shaped by metal material and forms, have for chimeric hole, the end of jointing 28.Periphery in the hole of lower plate 20C is concentrically formed with the groove of the ring-type inserted for O type ring 24.O type ring 24 as elastomeric element is formed by the material forming with thermal endurance.The internal diameter 2b of O type ring 24 is set as less than the external diameter 2a of the multiple diaphragm 20bi (i=1 ~ n, n are positive integer) forming diaphragm group 20B.Now, the outer peripheral edges of diaphragm group 20B are clamped in upper plate 20A and lower plate 20C each other.In addition, the ratio outer peripheral edges of diaphragm group 20B are supported by O type ring 24 closer to the part of its central side.

Between mutually opposing lower plate 20C and diaphragm group 20B, form compression chamber by the inner peripheral portion of the surface of diaphragm 20bi, the end face of lower plate 20C and O type ring 24.

Form multiple diaphragm 20bi of diaphragm group 20B, such as, supply by for by the runner 28a in jointing 28 material forming that the fluid come has corrosion resistance.In addition, the number forming multiple diaphragm 20bi of diaphragm group 20B is suitably selected according to the specification of pressure switch.

By welding, the outer peripheral edges of upper plate 20A and lower plate 20C are engaged with the state being clamped with diaphragm group 20B, thus become to be integrated, obtain diaphragm unit 20.Thus, fusing department 20D is formed at the peripheral part of upper plate 20A and lower plate 20C.And the diaphragm unit 20 obtained and above-mentioned housing 10 combine by linking metal parts 26.

Known compared with the structure of the diaphragm unit in the past shown in above-mentioned diaphragm unit 20 with such as patent documentation 1 and patent documentation 2, due to reason described later, in relatively high pressure specification, even if reduce the compression area of diaphragm group 20B, also the accuracy error of operating pressure can be suppressed, further, the bending minimizing of diaphragm group 20B can be suppressed within the limits prescribed, the structure of the maximum stress in bend value acting on diaphragm group 20B can be reduced.This improves the resistance to pressure of pressure switch.

When the structure of the diaphragm unit in the past shown in such as patent documentation 1 and patent documentation 2, as shown in Fig. 3 (A) and Fig. 4, the outer peripheral edges of diaphragm group 20 ˊ B are clamped as beam with both ends built-in by upper plate 20 ˊ A and lower plate 20 ˊ C.In this case, bending ω, the radius stress σ of diaphragm group 20 ˊ B is obtained based on following formula (1) ~ (3) _r, hoop stress σ _θ.

Mathematical expression (1)

$\mathrm{\ω}=\frac{{\mathrm{pa}}^4}{64D}{(1-\frac{r^2}{a^2})}^2.....\left(1\right)$

Mathematical expression (2)

${\mathrm{\σ}}_r=\stackrel{-}{+}\frac{3{\mathrm{pa}}^2}{{8h}^2}\{(1+v)-(3+v)\frac{r^2}{a^2}\}.....\left(2\right)$

Mathematical expression (3)

${\mathrm{\σ}}_{\mathrm{\θ}}=\stackrel{-}{+}\frac{3{\mathrm{pa}}^2}{{8h}^2}\{(1+v)-(1+3v)\frac{r^2}{a^2}\}.....\left(3\right)$

Wherein, p, a, D, r, ν, h are the aggregate thickness of the load of unit are, the radius in face met with stresses, flexural rigidity, distance apart from center, Poisson's ratio, overlapping multiple diaphragm 20bi respectively.In addition, flexural rigidity D such as mathematical expression (4) represents.Wherein, E is vertical coefficient of elasticity.

Mathematical expression (4)

$D=\frac{{\mathrm{Eh}}^3}{12\left({1-v}^2\right)}.....\left(4\right)$

Maximum deflection ω _maxbased on mathematical expression (1), mathematical expression (4) by following mathematical expression (5), (5 ') and obtain.

Mathematical expression (5)

${\mathrm{\ω}}_{\max }={\left(\mathrm{\ω}\right)}_{r=0}=\frac{{\mathrm{pa}}^4}{64D}=\frac{3(1-v^2)}{16}\·\frac{{\mathrm{pa}}^4}{{\mathrm{Eh}}^3}.....\left(5\right)$

Mathematical expression (5 ')

${\mathrm{\ω}}_{\max }=0.171\frac{{\mathrm{pa}}^4}{{\mathrm{Eh}}^3}.....\left(5^{,}\right)$

When ∵ ν=0.3,

Maximum radius stress σ _maxobtained by mathematical expression (6) based on mathematical expression (2) (r=a).

Mathematical expression (6)

${\mathrm{\σ}}_{\max }={\left({\mathrm{\σ}}_r\right)}_{r=a}=\stackrel{-}{+}\frac{{3\mathrm{pa}}^2}{{8h}^2}((1+v)-(3+v))=\±\frac{3}{4}\·\frac{{\mathrm{pa}}^2}{h^2}=\±0.75\frac{{\mathrm{pa}}^2}{h^2}.....\left(6\right)$

On the other hand, in an example of pressure switch of the present invention, as shown in Fig. 3 (B) and Fig. 5, the outer peripheral edges of diaphragm group 20B are clamped as beam with both ends built-in by upper plate 20A and lower plate 20C, and when the ratio outer peripheral edges of diaphragm group 20B are supported on O type ring 24 closer to the part of its central side, obtain bending ω, the radius stress σ of diaphragm group 20B based on following mathematical expression (7) ~ (9) _r, hoop stress σ _θ.Wherein, p, a, D, r, ν, h, b be the load of unit are respectively, the radius in face met with stresses, flexural rigidity, distance apart from center, Poisson's ratio, the aggregate thickness of overlapping multiple diaphragm 20bi, the radius in face that meets with stresses.In addition, flexural rigidity D mathematical expression described above (4) represents.

During (i) 0≤r≤b

Mathematical expression (7)

$\mathrm{\ω}=\frac{{\mathrm{pb}}^4}{16D}\{\frac{r^4}{{4b}^4}-\frac{r^2}{{2a}^2}+\frac{a^2}{b^2}-(1+\frac{{2r}^2}{b^2})1n\frac{a}{b}-\frac{3}{4}\}.....\left(7\right)$

Mathematical expression (8)

${\mathrm{\σ}}_r=\stackrel{-}{+}\frac{{3\mathrm{pb}}^2}{{8h}^2}\{(1+v)(\frac{b^2}{a^2}+41n\frac{a}{b})-(3+v)\frac{r^2}{b^2}\}.....\left(8\right)$

Mathematical expression (9)

(ii) during b≤r≤a

${\mathrm{\σ}}_{\mathrm{\θ}}=\stackrel{-}{+}\frac{{3\mathrm{pb}}^2}{{8h}^2}\{(1+v)(\frac{b^2}{a^2}+41n\frac{a}{b})-(1+3v)\frac{r^2}{b^2}\}.....\left(9\right)$

Mathematical expression (7 ')

$\mathrm{\ω}=\frac{{\mathrm{\π\β}}^4}{16D}\{(1-\frac{{\mathrm{\ρ}}^2}{{\mathrm{\α}}^2})\frac{{\mathrm{\α}}^2}{{\mathrm{\β}}^2}-\frac{{\mathrm{\ρ}}^2}{2{\mathrm{\α}}^2}-(1+\frac{{2\mathrm{\ρ}}^2}{{\mathrm{\β}}^2})1\mathrm{\ν}\frac{\mathrm{\α}}{\mathrm{\ρ}}+\frac{1}{2}\}.....\left(7^{,}\right)$

Mathematical expression (8 ')

${\mathrm{\σ}}_r=\stackrel{-}{+}\frac{{3\mathrm{pb}}^2}{8h^2}\{(1+v)(41n\frac{a}{r}+\frac{b^2}{a^2})+(1-v)\frac{b^2}{r^2}-4\}.....\left(8^{,}\right)$

Mathematical expression (9 ')

${\mathrm{\σ}}_{\mathrm{\θ}}=\stackrel{-}{+}\frac{{3\mathrm{pb}}^2}{{8h}^2}\{(1+v)(41n\frac{a}{r}+\frac{b^2}{a^2})+(1-v)\frac{b^2}{r^2}-4v\}.....\left(9^{,}\right)$

Maximum defluxion ω _maxobtained (r=0) by the mathematical expression (10) obtained in mathematical expression (7) substitution mathematical expression (4).

Mathematical expression (10)

${\mathrm{\ω}}_{\max }={\left(\mathrm{\ω}\right)}_{r=0}=\frac{{\mathrm{pb}}^4}{16D}\{{\left(\frac{a}{b}\right)}^2-1n\frac{a}{b}-\frac{3}{4}\}=\frac{3(1-v^2)}{4}\{{\left(\frac{a}{b}\right)}^2-1n\frac{a}{b}-\frac{3}{4}\}\·\frac{{\mathrm{pb}}^4}{{\mathrm{Eh}}^3}..\left(10\right)$

Mathematical expression (10 ')

${\mathrm{\ω}}_{\max }=\frac{3(1-v^2)}{4}\·{\left(\frac{b}{a}\right)}^4\{{\left(\frac{a}{b}\right)}^2-1n\frac{a}{b}-\frac{3}{4}\}\·\frac{{\mathrm{pa}}^4}{{\mathrm{Eh}}^3}.....\left(10^{,}\right)$

Maximum stress in bend σ _maxwhen b/a < 0.569 (when stress concentrates on center)

${\mathrm{\&sigma;}}_{\max }={\left({\mathrm{\&sigma;}}_r\right)}_{r=0}={\left({\mathrm{\&sigma;}}_{\mathrm{\&theta;}}\right)}_{r=0}=\stackrel{-}{+}\frac{{3\mathrm{pb}}^2}{{8h}^2}\left\{(1+v)({\left(\frac{b}{a}\right)}^2+41n\frac{a}{b})\right\}$

Mathematical expression (11)

${\mathrm{\&sigma;}}_{\max }=\stackrel{-}{+}\frac{3}{8}\&CenterDot;{\left(\frac{b}{a}\right)}^2\{(1+v)\&CenterDot;({\left(\frac{b}{a}\right)}^2+41\mathrm{na}\frac{a}{b})\}\frac{{\mathrm{pa}}^2}{h^2}......\left(11\right)$

In addition, bending stress becomes the maximum position width hour at the stress applied, and stress concentrates on central authorities, is the core of plectane, i.e. r=0 place, when the width of stress application is large, stress at the standing part of plectane, i.e. r=a place.Switching point is greater than or is less than value INF (=0.569) (Fig. 7 reference) with internal diameter radius ratio b/a to be changed.

During b/a > 0.569 (plectane on a large scale stress application time)

${\mathrm{\&sigma;}}_{\max }={\left({\mathrm{\&sigma;}}_r\right)}_{r=a}=\stackrel{-}{+}\frac{{3\mathrm{pb}}^2}{{8h}^2}\{(1+v)\&CenterDot;{\left(\frac{b}{a}\right)}^2+(1-v)\&CenterDot;{\left(\frac{b}{a}\right)}^2-4\}$

Mathematical expression (12)

${\mathrm{\&sigma;}}_{\max }=\&PlusMinus;\frac{3}{8}\&CenterDot;{\left(\frac{b}{a}\right)}^2\{4-2\&CenterDot;{\left(\frac{b}{a}\right)}^2\}\&CenterDot;\frac{{\mathrm{pa}}^2}{h^2}=\&PlusMinus;\frac{3}{4}\&CenterDot;{\left(\frac{b}{a}\right)}^2\{2-{\left(\frac{b}{a}\right)}^2\}\&CenterDot;\frac{{\mathrm{pa}}^2}{h^2}.....\left(12\right)$

Below, the following part of mathematical expression (10 ') is called flexibility factor α ₆, the following part of mathematical expression (11) and mathematical expression (12) is called stress coefficient β ₆, β ₆'.

Mathematical expression (13)

${\mathrm{\&alpha;}}_6=\frac{3(1-v^2)}{4}\&CenterDot;{\left(\frac{b}{a}\right)}^4\{{\left(\frac{a}{b}\right)}^2-1n\frac{a}{b}-\frac{3}{4}\}.....\left(13\right)$

During b/a < 0.569

Mathematical expression (14)

${\mathrm{\&beta;}}_6=\frac{3}{8}\&CenterDot;{\left(\frac{b}{a}\right)}^2\{(1+v)\&CenterDot;({\left(\frac{b}{a}\right)}^2+41n\frac{a}{b})\}.....\left(14\right)$

During b/a > 0.569

Mathematical expression (15)

${{\mathrm{\&beta;}}_6}^{\&prime;}\frac{3}{4}\&CenterDot;{\left(\frac{b}{a}\right)}^2\{2-{\left(\frac{b}{a}\right)}^2\}.....\left(15\right)$

When Poisson's ratio ν is 0.3, flexibility factor α ₆, stress coefficient β ₆, β ₆' change as Fig. 6 and Fig. 7 according to the change of the value of internal diameter radius ratio b/a.From Fig. 6 and Fig. 7 clearly, when internal diameter radius ratio b/a becomes 1, flexibility factor α ₆consistent with mathematical expression (5 '), stress coefficient β ₆' consistent with mathematical expression (6).

Such as, when 2a=φ 20,2b=φ 12, b/a=0.6.In addition, when Poisson's ratio is 0.3, is suitable for mathematical expression (13) and mathematical expression (15), as shown in Fig. 6 and Fig. 7, obtains α ₆=0.134, β ₆'=0.443.

Thus, maximum defluxion ω is calculated _maxvariable quantity and maximum stress in bend σ _maxvariable quantity when, maximum defluxion ω _maxvariable quantity be 21.6% (=(0.171-0.134)/0.171 × 100), maximum stress in bend σ _maxvariable quantity be 40.9% (=(0.75-0.443)/0.75 × 100).That is, the change of " amount of deflection " relevant to the pressure characteristic of diaphragm group 20B can be made to suppress for reduce about 21.6%, " the maximum stress in bend σ of diaphragm group 20B _maxvalue " reduce about 40.9%.

Fig. 2 represents the major part of other example of pressure switch of the present invention.

In addition, pressure switch is also closed type switch as shown in Figure 1 in the example shown in Fig. 2, is configured to comprise as staple: the diaphragm unit 30 be combined with one end of jointing 28, to link and the housing 10 of built-in a pair splicing ear 12 and 14, be configured in housing 10 and make the fixed contact 12a of a pair splicing ear 12 and axle 16P of travelling contact 14a opening and closing of splicing ear 14 and the axle guide member 16 of leading axle 16P according to the displacement of diaphragm group 30B described later with diaphragm unit 30.

Diaphragm unit 30 be configured to using the lower plate 30C be connected with one end of jointing 28 with the upper plate 30A that the open end periphery and O type ring 18 of housing 10 abut, be held on diaphragm group 30B between mutually opposing upper plate 30A and lower plate 30C, as the O type ring 34 of the elastomeric element of ring-type, support ring 36 be main key element.

Upper plate 30A by drawing, cut, die casting, forging etc., such as, is shaped by metal material and forms, across the gap of regulation opposite with the end face of axle guide member 16 configure.Upper plate 30A has for the through through hole 30a of the other end of axle 16P at central portion.

Lower plate 30C by drawing, cut, die casting, forging etc., such as, is shaped by metal material and forms, have for chimeric hole, the end of jointing 28.Periphery in the hole of lower plate 30C is concentrically formed with the groove of the ring-type inserted for O type ring 24, support ring 36.Formed by the material forming with thermal endurance as the O type ring 34 of elastomeric element, support ring 36.The internal diameter 2b of O type ring 34 is set as less than the external diameter 2a of the multiple diaphragm 30bi (i=1 ~ n, n are positive integer) forming diaphragm group 30B.Now, the outer peripheral edges of diaphragm group 30B are clamped in upper plate 30A and lower plate 30C each other.In addition, the ratio outer peripheral edges of diaphragm group 30B are more supported on support ring 36 and O type ring 34 by the part of its central side.

Between mutually opposing lower plate 30C and diaphragm group 30B, be formed with compression chamber by the inner peripheral portion of the surface of diaphragm 30bi, the end face of lower plate 30C and O type ring 34.

The multiple diaphragm 30bi forming diaphragm group 30B are such as formed by the material forming fluid come by the runner 28a supply in jointing 28 to corrosion resistance.In addition, the number forming multiple diaphragm 30bi of diaphragm group 30B is suitably selected according to the specification of pressure switch.

Engage by welding with the outer peripheral edges of the state upper plate 30A and lower plate 30C that clamp diaphragm group 30B, thus become to be integrated, obtain diaphragm unit 30.Thus, fusing department 30D is formed at the peripheral part of upper plate 30A and lower plate 30C.And the diaphragm unit 30 obtained and above-mentioned housing 10 combine by linking metal parts 26.

In such example, the bending minimizing of diaphragm group 30B also can be made to suppress within the limits prescribed, and the maximum stress in bend value acting on diaphragm group 30B can be reduced.

In addition, in an example of the present invention, be applicable to closed type switch, O type ring 24 and 34 is employed as elastomeric element, but be not limited to such example, such as, also go for open type switch, also can use as elastomeric element and there is flexible V-shaped ring, dihedral ring, there is flexible seal member, there is flexible bonding agent or encapsulant.

Claims (3)

1. a pressure switch, is characterized in that, possesses:

Shell, it has multiple splicing ears of at least one pair of travelling contact and fixed contact in inner side storage;

Diaphragm unit, itself and above-mentioned shell link, and have with supply operating pressure pipeline be connected and produce at least one diaphragm of displacement according to this operating pressure; And

Opening/closing unit, it makes travelling contact and the fixed contact opening and closing of above-mentioned splicing ear according to the displacement of the above-mentioned diaphragm of above-mentioned diaphragm unit,

The peripheral part of the diaphragm of above-mentioned diaphragm unit is fixed, and is supported by the elastomeric element of ring-type than the part of above-mentioned peripheral part closer to the central side of above-mentioned diaphragm.

2. pressure switch according to claim 1, is characterized in that,

The elastomeric element of above-mentioned ring-type and support ring are adjacent to configure.

3. pressure switch according to claim 1, is characterized in that,

The elastomeric element of above-mentioned ring-type has the diameter less than the diameter of the diaphragm of above-mentioned diaphragm unit.