US3729605A - Pressure-responsive electric switch - Google Patents

Pressure-responsive electric switch Download PDF

Info

Publication number
US3729605A
US3729605A US00215489A US3729605DA US3729605A US 3729605 A US3729605 A US 3729605A US 00215489 A US00215489 A US 00215489A US 3729605D A US3729605D A US 3729605DA US 3729605 A US3729605 A US 3729605A
Authority
US
United States
Prior art keywords
lever
spring
frame
snap
pressure
Prior art date
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
US00215489A
Other languages
English (en)
Inventor
J Andresen
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.)
Danfoss AS
Original Assignee
Danfoss AS
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 Danfoss AS filed Critical Danfoss AS
Application granted granted Critical
Publication of US3729605A publication Critical patent/US3729605A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • 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

Definitions

  • ABSTRACT The invention relates to a snap action electric switch Jan 12, l9' 7l Germany ..P2l 0] 196.1 assembly having fluid pressure operated means for biasing the lever means in the direction opposite the 1 [52] Cl "200/83 200/83 200/67 D biasing force of the snap action spring in response to Int. Cl. pressurized being directed to h chamber.
  • the invention relates to a pressure-responsive elec tric switch with an operating element which acts on a two-part'snap-action system, consisting of a lever and a snap-action spring, and against which element a spring force acts, the switch also having a casing.
  • An electric thermostat switch in which an operating element, subjected to the pressure of saturated steam, and a cylindrical rated-value spring, arranged coaxially with said element, act on'a rod which in turn engages a rigid lever of the snap-action system.
  • the arrnagement isaccommodated in a sheet-metal casing to which is riveted a sheet-metal strip which acts as a bearing for the snap-action spring. This arrangement is complicated, large and expensive.
  • bimetal switch in which the bimetal, firmly clamped at one end, together with a bent snapaction spring constitutes the snap-action system.
  • An extension connected to the snap-action spring acts upon the movable contact, which in the at-rest position is pressed against the fixed contact by its own spring force.
  • the object of the invention is to provide a pressureresponsive electric switch of the initially described kind, for example a thermostat or a pressostat, which may be of very small design and very cheap to produce.
  • this object is achieved by the lever itself taking the form of a spring and being secured at one end to the side walls of the casing, by the snap-action spring being mounted on a bearing formed on an end face of the casing, and by the operating element, designed as a pressure element, being secured to the base of the casing and connected to the lever by way of a plunger.
  • the casing is constituted by a sheet-metal part bent to the shape of a U and has only one end wall. This results in an extremely inexpensive component.
  • a set of central contacts may be fitted between the lever and the bottom of the casing, the moving contact being connected to the lever through an actuating element. In this way, the free space required in the casing on account of the length of the lever is economically utilized.
  • the vasin g may perform further functions.
  • one of the stops for the snap-action system may be formed on the side wall of the casing. Both stops may of course also be formed there.
  • Biasing is expediently achieved by bending the lever forward in the direction of the operating element at that end of thelever whereby it is secured.
  • the casing contains inclined slots each with a stepped locking portion for securing to tabs on the lever, the slots being closed up after the lever has been fitted therein.
  • FIG. 1 is a schematic section through a switch in accordance with the invention.
  • FIG. 2 is an end view of the switch of FIG. 1, as seen at the side where the set of contacts is located.
  • a casing l which has a base 2, side walls 3 and 4 and an end wall 5.
  • a port 6 Provided at the base is a port 6, with a pressure element 7 which comprises a diaphragm 8.
  • a passage 9 leads to the cavity 10 of the pressure element.
  • a plunger 11 extends through an opening 12 into the interior of the casing.
  • a snap-action system consists of a lever 13, which takes the form of a spring, and of a snap-action spring 14 having the shape of the Greek letter omega. The latter is mounted between the free end 15 of the lever 13 and a tab 16 which is formed on the end wall 5 of the casing.
  • the lever 13 has a rear end 15 which is clamped in the casing and is bent forward from the rest of the lever in the direction of the pressure element 10, to an extent depending upon the required rated-value.
  • the lever 13 has two lateral tabs 18 and 19 which are inserted in inclined slots 20. Each of the inclined slots merges with a stepped locking portion 21.
  • a contact insert 23 is fitted into the space between the lever 13 and the base 2.0fthe casing.
  • This insert contains an insulating block 24 in which are secured on the one hand a carrier 25 for a fixed contact 26 and on the other a contact spring 27 with a movable contact 28, the insulating block also carrying the associated connector 29.
  • An actuating element 30 having a collar 31 extends through an opening in the lever 13, an opening in the insert 23 and an opening in the contact spring 27.
  • stops 32 are formed on the side walls 3 and 4, these stops limiting the upward movement of the snap-action system.
  • the bias of the resilient lever 13 preponderates, and the downwardly directed force component of the snap-action spring 14 overcomes the force applied by the pressure element 7.
  • the actuating element 30 is consequently pressed into its lower end position in which the collar 31 bears on the insert 23 and movable contact 28 is separated from the fixed contact 26. If the pressure in the pressure unit now rises to a lever that exceeds the force component of the rated-value spring 14, then the system snaps suddenly over into the upper end position in which the lever 13 bears against the stops 32. Before the upper end position has, been reached, the mass of the snap-action system becomes separated from the contact spring 27 and the movable contact 28, so that only the small mass of this contact strikes the fixed contact 26.
  • the system snaps back into the initial position as illustrated when a predetermined pressure-difference has been passed through, and the movable contact 28 is only separated from the fixed contact 26 after the actuating element 30 has travelled a certain distance, so that sudden separation of the contacts takes place.
  • the pressure-difference can be adjusted by bending the tab 16.
  • the rated-value can be adjusted by bending the lever 13.
  • a simple covering or the like of plastics material may be fitted over the casing to meet particular assembly requirements.
  • a snap action electric switch assembly comprising, a frame, spaced apart abutment support means on said frame, a lever and a snap action spring between said.
  • said lever having a movable free end engaging said snap action spring, said snap action spring biasing said lever in one direction, fixed contact means mounted on said frame, a leaf spring attached to said frame and carrying a movable contact which is engageable with said fixed contact, an actuator element connected to said lever and to the free end of said leaf spring, fluid pressure chamber means connected to said frame, plunger means between said fluid pressure chamber means and said free end of said lever for biasing said lever in the direction opposite from said one direction in'response to said chamber means being pressurized.

Landscapes

  • Physics & Mathematics (AREA)
  • Fluid Mechanics (AREA)
  • Switches Operated By Changes In Physical Conditions (AREA)
  • Thermally Actuated Switches (AREA)
US00215489A 1971-01-12 1972-01-05 Pressure-responsive electric switch Expired - Lifetime US3729605A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
DE19712101196 DE2101196B2 (de) 1971-01-12 1971-01-12 Druckabhaengig gesteuerter elektrischer schalter

Publications (1)

Publication Number Publication Date
US3729605A true US3729605A (en) 1973-04-24

Family

ID=5795652

Family Applications (1)

Application Number Title Priority Date Filing Date
US00215489A Expired - Lifetime US3729605A (en) 1971-01-12 1972-01-05 Pressure-responsive electric switch

Country Status (7)

Country Link
US (1) US3729605A (enExample)
JP (1) JPS5126620B1 (enExample)
CH (1) CH534956A (enExample)
DE (1) DE2101196B2 (enExample)
FR (1) FR2121795B1 (enExample)
GB (1) GB1381043A (enExample)
IT (1) IT943226B (enExample)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0822567A3 (en) * 1996-07-30 1998-10-14 Firt S.r.l. Control thermostat for apparatus operating by thermal cycles
EP0907196A1 (en) * 1997-10-01 1999-04-07 PRODIGY ITALIANA S.r.l. Highly reliable thermostat for adjusting temperature in electric apparatus

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4266104A (en) * 1979-02-12 1981-05-05 Johnson Controls, Inc. Switch mechanism with independent toggle actuators

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2738397A (en) * 1954-10-29 1956-03-13 Gen Electric Temperature responsive control device
US3609270A (en) * 1969-02-14 1971-09-28 Danfoss As Electric reversing switch

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2738397A (en) * 1954-10-29 1956-03-13 Gen Electric Temperature responsive control device
US3609270A (en) * 1969-02-14 1971-09-28 Danfoss As Electric reversing switch

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0822567A3 (en) * 1996-07-30 1998-10-14 Firt S.r.l. Control thermostat for apparatus operating by thermal cycles
EP0907196A1 (en) * 1997-10-01 1999-04-07 PRODIGY ITALIANA S.r.l. Highly reliable thermostat for adjusting temperature in electric apparatus

Also Published As

Publication number Publication date
CH534956A (de) 1973-03-15
FR2121795A1 (enExample) 1972-08-25
FR2121795B1 (enExample) 1974-12-20
DE2101196B2 (de) 1972-03-09
GB1381043A (en) 1975-01-22
JPS5126620B1 (enExample) 1976-08-07
IT943226B (it) 1973-04-02
DE2101196A1 (enExample) 1972-03-09

Similar Documents

Publication Publication Date Title
US3302269A (en) Methods of making condition responsive devices
US5172114A (en) Tactile effect switch and keyboard using such a switch
US2487374A (en) Electric switch
US3609270A (en) Electric reversing switch
US2460087A (en) Snap-action electric switch
GB1233400A (enExample)
US2425159A (en) Electric snap switch
US2814686A (en) Warp switch
US3729605A (en) Pressure-responsive electric switch
US2854536A (en) Snap-action electric switches
US3735069A (en) Snap-action electric switch
US3335242A (en) Condition responsive devices
US3735080A (en) Snap-action electric switch
US2466458A (en) Electric snap switch
US2769048A (en) Electrical apparatus
US4052581A (en) Switch with movable and fixed contacts
US3673535A (en) Electrical switch having a snap blade means and method of calibrating the same or the like
US3238337A (en) Thermostatic switch having press fit motion translator member
US3236963A (en) Pressure switch
US2824933A (en) Miniature switch
US3995245A (en) Thermostat construction and method of making the same
US3472980A (en) Disk spring motion converter
US3365557A (en) Pressure responsive diaphragm operated device
US3304385A (en) Pneumatic actuator with folded diaphragm
US3958091A (en) Snap-action electric switch, and contact blade structure therefor