US3352983A - Pressure switch and electrical switch therefor - Google Patents

Pressure switch and electrical switch therefor Download PDF

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Publication number
US3352983A
US3352983A US474201A US47420165A US3352983A US 3352983 A US3352983 A US 3352983A US 474201 A US474201 A US 474201A US 47420165 A US47420165 A US 47420165A US 3352983 A US3352983 A US 3352983A
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US
United States
Prior art keywords
spring
force
switch
actuating
point
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Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US474201A
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English (en)
Inventor
Johannus J Cools
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Controls Company of America
Original Assignee
Controls Company of America
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Controls Company of America filed Critical Controls Company of America
Priority to US474201A priority Critical patent/US3352983A/en
Priority to GB48528/65A priority patent/GB1120355A/en
Priority to DE19651515595 priority patent/DE1515595C3/de
Priority to NL656517224A priority patent/NL150605B/xx
Priority to FR66736A priority patent/FR1484448A/fr
Application granted granted Critical
Publication of US3352983A publication Critical patent/US3352983A/en
Priority to AU31038/67A priority patent/AU417238B2/en
Priority claimed from AU31038/67A external-priority patent/AU417238B2/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
    • H01H5/00—Snap-action arrangements, i.e. in which during a single opening operation or a single closing operation energy is first stored and then released to produce or assist the contact movement
    • H01H5/04—Energy stored by deformation of elastic members
    • H01H5/06—Energy stored by deformation of elastic members by compression or extension of coil springs
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
    • H01H35/00—Switches operated by change of a physical condition
    • H01H35/24—Switches operated by change of fluid pressure, by fluid pressure waves, or by change of fluid flow
    • H01H35/26—Details
    • H01H35/2607—Means for adjustment of "ON" or "OFF" operating pressure
    • H01H35/2614—Means for adjustment of "ON" or "OFF" operating pressure by varying the bias on the pressure sensitive element
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
    • H01H35/00—Switches operated by change of a physical condition
    • H01H35/24—Switches operated by change of fluid pressure, by fluid pressure waves, or by change of fluid flow
    • H01H35/26—Details
    • H01H35/2657—Details with different switches operated at substantially different pressures

Definitions

  • a general object of this invention is to provide an improved pressure switch.
  • Another object of this invention is to provide a pressure switch which exhibits improved electrical characteristics.
  • Another object of this invention is to provide a pressure switch construction which alfords improved maximum and minimum trip and reset differentials at both low and high trip pressures.
  • a further object of this invention is to improve the electrical characteristics of an electrical snap-action switch.
  • a more specific object of this invention is to provide a pressure switch and/or an electrical toggle-type switch wherein switching from one position to another starts from a condition where the movable contact is held in engagement with a fixed contact with adequate contact pressure to carry a substantial electrical load.
  • Another object of this invention is to provide a multiple level pressure switch which affords improved maximum and minimum diflierentials between the trip levels and the reset levels of the switch assemblies of the pressure switch.
  • a still further object of this invention is to provide for independent adjustment of each of the switch assem blies of a multiple level pressure switch.
  • this invention contemplates a toggle-type switch construction wherein a spring, in addition to the toggle spring, is arranged to oppose an actuating force acting to move the movable contact from one position to another, for example the force exerted through the diaphragm of a pressure switch.
  • This spring and the toggle spring are selected so that switching starts before the force component of the toggle spring holding the movable contact on a stationary contact is reduced to zero.
  • the spring rate of the toggle spring is negative in this arrangement and it and the spring rate of the additional spring, commonly referred to as the calibrating spring, are selected such that the spring rate of the calibrating spring is exceeded by the negative spring rate of the toggle spring at a point before the toggle spring is moved to its overcenter position.
  • switch construction has general application wherever a snap action switch is used it finds particular application in pressure switches and in multiple level as well as single level pressure switches.
  • switch assemblies be operatively isolated to permit independent adjustment. This is preferably achieved by providing stops which limit switch travel toward both trip and reset positions.
  • FIG. 1 is a sectional view through a dual level pressure switch taken generally along line 11 of FIG. 2 and illustrating one of the switch assemblies thereof in a reset position;
  • FIG. 2 is a 2-2 of FIG. 1
  • FIG. 3 is a sectional view taken generally along line 33 of FIG. 2 and illustrating the other switch assembly in a trip position;
  • FIG. 4 is a schematic illustration of the dual level pressure switch illustrating one switch assembly in a condition just prior to trip and the other switch assembly in a reset condition;
  • FIG. 5 is a plotting of diaphragm actuating force against diaphragm movement illustrating both trip and reset curves
  • FIG. 6 is a plotting of contact pressure against diaphragm movement again illustrating both trip and reset curves.
  • pressure switch 10 includes housing 12 and metal cap 14 rolled onto flange 16 with diaphragm 18 clamped between the sectional view taken generally alone line provide for connecting the pressure switch to an external source the pressure of which used as a basis for actuating the invention is preferably embodied ponents of switch assembly 26 which are identical to those of switch 24.
  • Switch assembly 24 is a toggle-type switch having a selectively establish a circuit through
  • a toggle spring is compressed between web 52 and tongue 44 to cooperate in providing overcenter switchbarrel spring 56 but other forms of toggle springs can be used without departing from the scope of this invention.
  • Movement of switch blade 38 between the reset and correspondingly the angle of the barrel spring with the rails decreases.
  • a force is applied to the switch assembly in a given direction to move the rails, tongue and spring to a point of coincidence whereupon further movement in that direction switches the movable contact from one contact to the other with a snap action.
  • movement from the reset to trip position is effected by an increase in pressure in chamber 29 with the resultantdiaphragm movement being toward the switch assembly whereas movement from the trip to the reset position occurs as a result of a reduction in pressure in chamber with the resultant diaphragm movement being away from the switch assembly.
  • the pressure switch also includes a calibrating spring system which exerts a force in opposition to the actuating force exerted through the diaphragm in accordance with the pressure in chamber 20.
  • switch assembly 24 is connected to diaphragm 18 through block 58 and bridge member 60.
  • Block 58 includes a flange 62 and tongue 44 of the switch assembly is clamped between flange 62 and shoulder 64 of block 58 to provide a connection between the tongue and diaphragm and establish an actuating point A through which the actuating force on the diaphragm acts on the switch assembly.
  • Bridge 66 engages block 58 through pin 66 and the connection between bridge 60 and diaphragm 18 is completed through pivot arm 68 which is formed from backing plate 70 connected to the diaphragm and with pivot arm 68 extending into a notch 72 in the lower side of bridge 60.
  • the above mentioned calibrating spring system includes springs 74 and 76 which are arranged to oppose movement of the diaphragm, and correspondingly switch assembly 24, in response to an increase in pressure in chamber 20 and also, when switch assembly 24 is in its trip position, to move the switch assembly toward a reset position in response to a decrease in pressure in chamber 20.
  • the force necessary to displace the switch tongue sufficiently to achieve switching is determined by the barrel spring, which has both a vertical and horizontal force component at the actuating point and, in the just-discussed prior art constructions, to a greater extent by the calibraing spring system.
  • this invention makes use of an arrangement whereby switching starts while the barrel spring still has a vertical force component. From this point switching proceeds dynamically and the movable contact is moved instantaneously through the Zero contact pressure point. Accordingly, there is no dwell at or near zero contact pressure so that the switch can carry greater electrical loads.
  • the barrel spring has an effective vertical spring rate which is a negative spring rate in that the force necessary for movement of the actuating point in opposition to the barrel spring forces decreases as the overcenter position is approached.
  • This 4- negative vertical rate of the barrel spring becomes more negative as the overcenter position is approached.
  • the spring system and diaphragm force Prior to switching to the reset position the spring system and diaphragm force are stable at any given point but when the reduction in the vertical component of the barrel spring for a given increment of movement becomes more negative than the positive spring rate of the calibrating spring the system becomes unstable with the calibrating spring overcoming the actuating force and dynamic switching occurs from a point before the overcenter position is reached.
  • Portion BD of the trip curve is representative of the characteristics of a switch including a single calibrating spring influencing switch operation, and the reset curve with a single calibrating spring would be the inverse of portion BD as is indicated by the reset curve in FIG. 5, the significance of the reset curve being segmented will become apparent as this description proceeds.
  • the spring force decreases until the switching or trip point is reached, at which time the barrel spring would go overcenter and contributes its force to switch movement rather than oppose it. Comparing FIGS. and 6, for the same dia phragm movement, or movement of the actuating point, it will be seen that switching starts, on both trip and reset, at a point where contact pressure is still maintained. In other words, the contact pressure curves also rise to a peak and then fall off but the fall-off after switching starts is not gradual since the switch is into dynamic motion and the travel is substantial, rapid and with a snap action.
  • the calibrating spring was considered as acting directly above the actuating point.
  • This arrangement places a severe limitation on the maximum available trip force while maintaining dynamic switching and in order to stay within the realm of feasibility a variation of this arrangement is preferred.
  • Maximum available trip pressure is determined by the buckling or collapsing force of the spring which, in turn, is related to the spring rate. With a light spring rate the collapsing force or, put another way, the maximum loading before the spring is collapsed is too low for practical use in connection with, for example, pressure switching as used in appliances. If the calibrating spring is moved toward the anchor point of the switch blade the spring rate of the spring itself can be increased without affecting dynamic switching.
  • the spring rate can be increased four times without changing the effective spring rate acting at the actuating point.
  • Increasing the spring rate four times multiplies the buckling force of the spring by four times resulting in doubling the effective buckling force (maximum available trip pressure) or actuating force at the actuating point, so that by moving the calibrating spring half way between the anchor point and actuating point the maximum available trip force is doubled without changing the effective spring rate opposing the actuating force and without losing the benefit of dynamic switching.
  • other positions between the actuating and anchor points with corresponding increases in spring rate over that which could be used at the actuating point are possible.
  • both springs are opposing the actuating force and the two springs must be selected so that their combined effective spring rate falls within the parameters previously discussed, that is they must not be so great that at some time prior to the toggle spring going overcenter the numerical negative rate of the toggle spring cannot become greater than the combined positive rate of the two springs.
  • the spring rates of springs 74 and 76 must be sufficiently light to permit the negative spring rate of the toggle spring to exceed the combined spring rate of springs 74 and 76 before the switch goes physically overcenter. With this arrangement both springs 74 and 76 can be separately adjusted and preloaded to effect both the desired trip and reset pressures.
  • FIGS. 5 and 6 In operation and with reference to FIGS. 1 and 4 and the curves of FIGS. 5 and 6, as the pressure in chamber 20 increases diaphragm 18, block 58 and switch tongue 44 move upwardly. This upward movement continues as the pressure on the diaphragm increases and FIG. 5 plots actuating force against diaphragm movement and FIG. 6 plots contact pressure against diaphragm movement for both trip and reset operation, with FIG. 6 including an indication of contact pressure at trip and reset. Because of the lost motion connection between block 58 and pin 90, only spring 74 and the vertical force component of the toggle spring oppose the actuating force during initial movement and the trip curves proceed as illustrated in FIGS. 5 and 6.
  • switch assembly 24 is illustrated in a position just prior to trip or in a condition corresponding to point E on the trip curve. From point E the actuating force increases with virtually no diaphragm movement as illustrated by the straight vertical line portion of the trip curve.
  • a relatively constant contact pressure is maintained until the requisite actuating force is reached at trip point F whereupon dynamic switching occurs and starts at a sufficient contact pressure I (FIG. 6) to permit a relatively high electrical load to be carried.
  • the actuating force falls off after switching starts because the vertical component of the toggle continues to decrease to the overcenter position after which it is reversed in direction and acts in the same direction as the actuating force.
  • switch assembly 24 assumes trip position as illustrated in FIG. 3 in connection with switch assembly 26.
  • the reset operaton of the switch assembly will now be described and in connection with switch assembly 26.
  • pressure in chamber 20 decreases the actuating force through the diaphragm decreases and springs 74 and 76' force block 58 and tongue 44 downwardly.
  • springs 74' and 76' expand and the vertical force component of the toggle spring is opposing springs 74 and 76' but has a negative spring rate.
  • the actuating force decreases the diaphragm and switch tongue 44' move downwardly with the contact pressure falling off and the vertical force component of the toggle spring decreasing at a progressively greater rate.
  • Point I on the reset curve indicates that reset starts from a point of substantial contact pressure.
  • the vertical portions of the trip and reset curves in FIG. 5 have been offset for better illustration but it will be appreciated that in practice they are virtually coincident.
  • springs 74 and 74 establish the reset pressures whereas the trip pressure is established by the combination of springs 74, 74 and 76, 76'.
  • the stop in one direction is provided by faces 94 and 96 of housing 12 and in the other direction by carriers 32 and 32.
  • the trip and reset pressures of switch assembly 24 will be greater than those of switch assembly 26 and, with the provision of the limits on travel of the switch lever, adjustment of one switch blade will not affect the other switch blade so long as this relationship between the respective trip and reset pressures is maintained and the differentials between the two do not fall below a prescribed minimum pressure, for example three to seven tenths of an inch of water volume pressure for a typical pressure installation.
  • terminal plates 34 and 34' are made of resilient material and are anchored at one end to body 12 by rivets 36 and 36 and have their other end free and engaged by adjusting screws 98 and 98'. The adjusting screws work against terminal plates 34 and 34' to increase the contact gap and, to reduce the contact gap, release the terminal plates for movement due to their resiliency.
  • a fixed contact gap is set by manipulation of screws 93 and 98 and spring 74, 74 and 76, 76 are adjusted by manipulating seats 78, 78 and 88, 88' to vary the reset and trip levels respectively.
  • a pressure switch comprising,in combination,
  • a switch assembly including a contact supporting member, an actuated member, and a toggle spring acting between said contact supporting member and said actuated member and mounted for overcenter operation to produce movement of the contact supporting member to either one of two positions, said toggle spring acting to hold said contact supporting member in either of said positions and passing overcenter as the contact supporting member moves from one position to the other,
  • the characteristics of said spring means and toggle spring being such that in movement from either of said positions to the other the combined spring rates of said spring means and toggle spring become negative before the toggle spring passes overcenter to thereby initiate switching before said toggle spring force component reverses in direction and dynamically switches said contact carrying member from one position to another.
  • a multiple level pressure switch comprising, in combination,
  • first and second switch assemblies each comprising a contact supporting member, an actuated member and a toggle spring connected between said actuated member and said contact supporting member to produce overcenter action of said contact supporting member to either one of two positions,
  • lever means interposed between each of said spring means and said actuated members and connected to and movable with said actuated members
  • said spring means connected to each of said lever means and exerting a force on said actuated members through said lever means in opposition to the force of said diaphragm means
  • a pressure switch including a toggle-type switch assembly movable overcenter to trip and reset positions and including a toggle spring having a force component in both of said trip and reset positions actuating to hold said switch assembly in said trip and reset positions respectively,
  • said spring means having a predetermined spring rate and said force component of said toggle spring diminishing as said switch assembly moves from both said trip and reset positions toward the other at a rate which exceeds the spring rate of said spring means before said toggle spring is moved physically to its overcenter position so that switching from one of said trip and reset positions to the other occurs before the force component acting in said trip and reset directions reverses or reduces to zero.
  • the pressure switch of claim 5 including means mounting said spring means at a point removed from said actuatmg point so that the spring rate and force of said spring means can be greater than the spring rate and force thereof applied at said actuating point.
  • a switch comprising, in combination,
  • the spring rate of said spring means being such that in movement from both said first and second positions to the other position the reduction in the force component of said toggle spring acting in the direction of said spring means and said actuating force exceeds the spring rate of said spring means before said toggle spring reaches its overcenter position.
  • a pressure switch comprising, in combination,
  • a switch assembly including a contact supporting member, an actuated member, a toggle spring acting between said contact supporting member and said actuacted member and mounted for overcenter operation to produce movement of the contact supporting member to either one of two positions for engagement with either one of said first and second contacts, said toggle spring acting to hold said contact supporting member in either of said positions and passing overcenter as said contact supporting member moves from one position to the other,
  • said toggle spring exerting a force component on said actuating member and said actuating point parallel to the force direction of said spring means and diaphragm means
  • first and second contacts comprise a fixed trip contact and a reset contact and including means supporting said reset contact for movement relative to said trip contact to adjust the reset point of said pressure switch.
  • a multiple level pressure switch comprising, in
  • first and second switch assemblies each comprising first and second relatively spaced contacts, a contact supporting member, an actuated member and a toggle spring connected between said actuated member and said contact supporting member to produce overcenter action of said contact supporting member to either one of two positions in engagement with either one of said first and second contacts,
  • toggle springs exert a force on said actuating members at said actuating point parallel to the force direction of said spring means and diaphragm means'and the characteristics of said spring means and toggle spring .are such that their combined spring rates become negative before the toggle springs pass overcenter to thereby initiate switching before said force component of said toggle springs reverse in direction and dynamically switch said contact supporting members from one position to another.
  • first and second contacts of each of said switch assemblies comprise a fixed trip contact and a reset contact, and including means supporting said reset contacts for movement relative to said trip contact to adjust the reset points of said pressure switch.
  • a snap switch including a contact supporting member and an actuated member having a toggle spring acting therebetween and mounted for overcenter action to produce movement of the contact supporting member from one position to another position, the toggle spring acting to hold the contact supporting member in either position and passing overcenter as the contact supporting member moves from one position to the other,
  • said contact supporting member and the actuated member mounted for pivotal movement and said spring means exerting a force on the actuated member and being physically positioned between the actuating point and the pivot point of the actuated memher,
  • the characteristics of the spring means and the toggle spring being selected so that their combined spring rates become negative before the toggle spring passes overcenter to thereby initiate switching action
  • a snap switch including a contact supporting member and an actuated member having a toggle spring acting .therebetween and mounted for overcenter action to produce movement of the contact supporting member from one position to another position, the toggle spring acting to hold "the contact supporting member in either position and passing overcenter as the contact supporting member moves from one position to the other,
  • a pressure switch comprising, in combination,
  • a switch assembly including a contact supporting member, an actuated member, and a toggle spring acting between said contact supporting member and said actuated member and mounted for overcenter operation to produce movement of the contact supporting member to either one of two positions, said toggle spring acting to hold said contact supporting member in either of said positions and passing overcenter as the contact supporting member moves from one position to the other,
  • said contact supporting member and said actuated member mounted for pivotal movement and said spring means being physically positioned between said-actuating point and the pivot point of said actuated member
  • said toggle spring exerting a force component on said actuated member at said actuating point parallel to the force direction of said spring means and diaphragm means
  • a pressure switch comprising, in combination,
  • a switch assembly including a contact supporting member, an actuated member, and a toggle spring acting between said contact supporting member and said actuated member and mounted for overcenter-operation to produce movement of the contact supporting member to either one of two positions, said toggle spring acting to hold said contact supporting member in either of said positions and passing overcenter as the contact supporting member moves from one position to the other,
  • a multiple level pressure switch comprising, in
  • first and second switch assemblies each comprising a contact supporting member, an actuated member and a toggle spring connected between said actuated member and said contact supporting member to produce overcenter action of said contact supporting member to either one of two positions,
  • a bridge member connecting said diaphragm means to each of said actuated members and defining an actuating point at each switch assembly through which the actuating force of said diaphragm is applied to said actuated members, said bridge member also connecting said first and second switch assemblies to each other,
  • lever means interposed between each of said spring means and said actuated members and connected to and movable with said actuated members
  • said toggle springs exerting a force component on said actuated members at said actuating point parallel to the force direction of said spring means and diaphragm means and the characteristics of said spring means and toggle springs being such that their combined spring rates become negative before the toggle springs pass overcenter to thereby initiate switching before said force component of said toggle springs reverse in direction and dynamically switch said contact members from one position to another.
  • a multiple level pressure switch comprising, in combination,
  • first and second switch assemblies each comprising a contact supporting member, an actuated member and a toggle spring connected between said actuated member and said contact supporting member to produce overcenter action of said contact supporting member to either one of two positions, diaphragm means, means connecting said diaphragm means to each of said actuated members and defining an actuating point at each switch assembly through which the actuating force of said diaphragm is applied to said actuated members, spring means, lever means interposed between each of said spring means and said actuated members and connected to and movable with said actuated members, said spring means connected to each of said lever means and exerting a force on said actuated members through said lever means in opposition to the force of said diaphragm means, means for adjusting the force with which said spring means oppose the force of said diaphragm means, means defining limit stops in the path of movement of each of said switch assemblies and arranged for engagement with and to limit movement of said lever means toward both of the positions of said switch assemblies, and second spring means associated

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  • Physics & Mathematics (AREA)
  • Fluid Mechanics (AREA)
  • Switches Operated By Changes In Physical Conditions (AREA)
US474201A 1965-06-29 1965-06-29 Pressure switch and electrical switch therefor Expired - Lifetime US3352983A (en)

Priority Applications (6)

Application Number Priority Date Filing Date Title
US474201A US3352983A (en) 1965-06-29 1965-06-29 Pressure switch and electrical switch therefor
GB48528/65A GB1120355A (en) 1965-06-29 1965-11-16 Improvements in snap-action switches
DE19651515595 DE1515595C3 (de) 1965-06-29 1965-11-19 Elektrischer Sprungschalter
NL656517224A NL150605B (nl) 1965-06-29 1965-12-31 Momentschakelaar met op een zijde van een schakeltong aangrijpend bedieningsonderdeel en op de tegenovergestelde zijde daarvan aangrijpende terugstelveer.
FR66736A FR1484448A (fr) 1965-06-29 1966-06-23 Commutateur rapide
AU31038/67A AU417238B2 (en) 1967-12-11 Snap action switches

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US474201A US3352983A (en) 1965-06-29 1965-06-29 Pressure switch and electrical switch therefor
AU31038/67A AU417238B2 (en) 1967-12-11 Snap action switches

Publications (1)

Publication Number Publication Date
US3352983A true US3352983A (en) 1967-11-14

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Application Number Title Priority Date Filing Date
US474201A Expired - Lifetime US3352983A (en) 1965-06-29 1965-06-29 Pressure switch and electrical switch therefor

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US (1) US3352983A (OSRAM)
GB (1) GB1120355A (OSRAM)
NL (1) NL150605B (OSRAM)

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3594521A (en) * 1968-06-18 1971-07-20 Patinvest Ag Electric snap switch with fluid-actuated toggle mechanism
US3617665A (en) * 1968-12-13 1971-11-02 Controls Co Of America Snap-action pressure-sensitive switch with safety feature responsive to contact welding
DE3007305A1 (de) * 1980-02-27 1981-09-03 Behr-Thomson Dehnstoffregler Gmbh, 7014 Kornwestheim Thermoschalter mit einem von einem dehnstoffelement betaetigten schnappschalter
US4464551A (en) * 1982-05-14 1984-08-07 General Electric Company Electric circuit controlling device and method of operating same
EP0325705A3 (de) * 1988-01-23 1990-12-27 Rafi GmbH & Co Elektrotechnische Spezialfabrik Verstellwegmesseinrichtung
US4990728A (en) * 1989-05-12 1991-02-05 Eaton Corporation Pressure switch and sub-assembly therefor
US20150109079A1 (en) * 2013-10-18 2015-04-23 Technology Power International Limited Rapid tri-state bidirectional switching device
CN110391110A (zh) * 2019-09-04 2019-10-29 济南迈克阀门科技有限公司 一种消防用双输出式可调压压力开关

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
IT8653186V0 (it) * 1986-03-25 1986-03-25 Greg Di S Greganti E C S A S Dispositivo sensore di pressione per pneumatici di autoveicoli

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2175721A (en) * 1938-02-09 1939-10-10 Honeywell Regulator Co Snap-acting thermostatic switch
US2318734A (en) * 1939-12-07 1943-05-11 Honeywell Regulator Co Snap action switch
US3160725A (en) * 1960-06-27 1964-12-08 Danfoss Ved Ing M Clausen Thermostat with adjustable temperature range and combined semi-automatic operator
US3187136A (en) * 1961-10-16 1965-06-01 Robertshaw Controls Co Multiple pressure switch construction
US3233056A (en) * 1962-07-30 1966-02-01 Walter Beck K G Kontroll Und F Adjustable condition-responsive plunger-operated snap-action electrical switch
US3249710A (en) * 1960-05-23 1966-05-03 Maxson Electronics Corp Snap action electrical switch with contact flutter attenuation means

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2175721A (en) * 1938-02-09 1939-10-10 Honeywell Regulator Co Snap-acting thermostatic switch
US2318734A (en) * 1939-12-07 1943-05-11 Honeywell Regulator Co Snap action switch
US3249710A (en) * 1960-05-23 1966-05-03 Maxson Electronics Corp Snap action electrical switch with contact flutter attenuation means
US3160725A (en) * 1960-06-27 1964-12-08 Danfoss Ved Ing M Clausen Thermostat with adjustable temperature range and combined semi-automatic operator
US3187136A (en) * 1961-10-16 1965-06-01 Robertshaw Controls Co Multiple pressure switch construction
US3233056A (en) * 1962-07-30 1966-02-01 Walter Beck K G Kontroll Und F Adjustable condition-responsive plunger-operated snap-action electrical switch

Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3594521A (en) * 1968-06-18 1971-07-20 Patinvest Ag Electric snap switch with fluid-actuated toggle mechanism
US3617665A (en) * 1968-12-13 1971-11-02 Controls Co Of America Snap-action pressure-sensitive switch with safety feature responsive to contact welding
DE3007305A1 (de) * 1980-02-27 1981-09-03 Behr-Thomson Dehnstoffregler Gmbh, 7014 Kornwestheim Thermoschalter mit einem von einem dehnstoffelement betaetigten schnappschalter
US4464551A (en) * 1982-05-14 1984-08-07 General Electric Company Electric circuit controlling device and method of operating same
EP0325705A3 (de) * 1988-01-23 1990-12-27 Rafi GmbH & Co Elektrotechnische Spezialfabrik Verstellwegmesseinrichtung
US4990728A (en) * 1989-05-12 1991-02-05 Eaton Corporation Pressure switch and sub-assembly therefor
US20150109079A1 (en) * 2013-10-18 2015-04-23 Technology Power International Limited Rapid tri-state bidirectional switching device
US9184010B2 (en) * 2013-10-18 2015-11-10 Technology Power International Limited Rapid tri-state bidirectional switching device
CN110391110A (zh) * 2019-09-04 2019-10-29 济南迈克阀门科技有限公司 一种消防用双输出式可调压压力开关
CN110391110B (zh) * 2019-09-04 2024-04-26 济南迈克阀门科技有限公司 一种消防用双输出式可调压压力开关

Also Published As

Publication number Publication date
DE1515595A1 (de) 1969-08-14
NL6517224A (OSRAM) 1966-12-30
GB1120355A (en) 1968-07-17
DE1515595B2 (de) 1975-09-25
NL150605B (nl) 1976-08-16
AU417238A (en) 1971-09-21

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