US2574869A - Switch - Google Patents

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Publication number
US2574869A
US2574869A US64305A US6430548A US2574869A US 2574869 A US2574869 A US 2574869A US 64305 A US64305 A US 64305A US 6430548 A US6430548 A US 6430548A US 2574869 A US2574869 A US 2574869A
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US
United States
Prior art keywords
strip
bearing
point
switch
temperature
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
US64305A
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English (en)
Inventor
Green John Dudley Francis
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.)
Pye Electronic Products Ltd
Original Assignee
Pye Ltd
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 Pye Ltd filed Critical Pye Ltd
Application granted granted Critical
Publication of US2574869A publication Critical patent/US2574869A/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
    • H01H37/00—Thermally-actuated switches
    • H01H37/02—Details
    • H01H37/10—Compensation for variation of ambient temperature or pressure
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
    • H01H37/00—Thermally-actuated switches
    • H01H37/02—Details
    • H01H37/60—Means for producing snap action
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T74/00—Machine element or mechanism
    • Y10T74/18—Mechanical movements
    • Y10T74/18856—Oscillating to oscillating
    • Y10T74/18864—Snap action

Definitions

  • An object of the invention is to provide a snap-action time-delay switch which is useful for controlling the high tension supply to thermionic tubes as well as for other purposes. Another object is to provide a thermal timedelay switch which is compensated for by changes in ambient temperature. Another object is to achieve the foregoing objects with a switch mechanism which is simple and economical to construct and manufacture and is reliable and durable in service.
  • FIG. 1 and 2 are diagrams illustrating the principle of operation of the switch.
  • Fig. 3 is a schematic side view of one embodiment of a thermal time-delay switch according to the invention.
  • a spring strip ID of bowed cross-section is held fast at one end by fixture to a suitable anchorage i I, and if a bearing or stop represented by arrow i2 is positioned to engage the convex side of the strip ID at a point spaced from the anchorage il, then the application to the concave side of the stri of a force represented by arrow i3 and applied at some point along the portion M of the strip between the point of application of the bearing i2 and the free end of the strip, will have the portion M of the strip longitudinally about the bearing I!
  • the bending force l3 may be applied at any point along the portion id, but the nearer the point of application is to the bearing II, the smaller will be the displacement of the point of application of the force I3 needed to flex the strip.
  • thermal switch embodying the invention will now be described with reference to Fig. 3.
  • a time-delay switch for automatically connecting the high tension supply to such tubes only after the lapse of a predetermined time interval from switching on the apparatus, which is sufficient to allow the filaments or heaters of the tubes to attain their working temperature.
  • the thermal time-delay switch schematically depicted in Fig. 3 may be employed for this purpose, as well as for other purposes.
  • the switch comprises an insulating base plate on which is mounted an insulating block or pillar ii to which one end of a spring strip 62 of bowed cross-section is rigidly fixed with its convex side facing the base plate 60, the free end of the strip carrying a contact 63.
  • a bi-metallic strip element 64 in the form of a bridge having one end portion is clamped on to the fixed end of the strip 62 by means of a fixing bolt 66 which passes through the portion ll of the bi-metallic strip, through the strip 62 and the block GI and secures that assembly'to the base plate 60.
  • the bi-metallic strip 64 has an intermediate portion 6!
  • Another strip 69 also of bridge form, has one end portion 10 secured to the block Si by means of the bolt 66 against the convex side of the strip 62, an intermediate portion ll spaced from the strip 62 and a free end portion 12 which bears against the convex side of the strip 62 at a point intermediate the block II and end 68 of strip 64.
  • a stationary contact I! spaced from contact 63 is carried on the free end of a further strip 14 which is fixed at its other end to the base plate 60.
  • the bi-metallic strip 64 is provided with a heater winding II, c.
  • the heater circuit is completed through the strips 64, 62 and bolt 66 to a terminal 11 on the base plate 60.
  • the fixed end of the strip 14 is connected to another terminal 18 on the base plate 60.
  • the circuit to be controlled by the switch is connected to theterminals l1 and 18, thereby connecting the contacts 63 and '13 in such circuit.
  • the terminals 16 and I! are connected to a circuit for supplying heating current to the winding 15.
  • the time delay between the closing of the heater circuit and the closing of the switch may be adjusted by adjustment of the initial pressure of the bearing 12 on, or its spacing from, the strip 62, and the spacin of the stationary contact 13 from the contact 63.
  • adjusting screws 79 and 80 are threaded through the base plate 60 and bear against the strips 69 and 14 respectively, these strips being made resilient so that they maintain engagement with their screws.
  • both the strips- 69 and 14 are constituted by bi-metallic strips of the same thermal characteristics as the main bi-metallic strip 64 so that any change in ambient temperature affects the three strips equally and causes them to move in the same direction by the same amount.
  • the strip 69 bends and moves the bearing 12 away from the contact-carrying strip 62 by the same amount as the bi-metallic strip 84 bends and moves its end 68 towards the strip 62, so that such movement of the end 68 cannot abruptly flex the strip 62, and consequently the time required to heat the main bi-metallic strip 64 by means of the heater winding 15 sufflciently to cause it to efiect the abrupt flexing of the strip will remain constant.
  • a thermal switch device comprising a base member, a bowed-section spring strip, means for rigidly supporting one point of said strip relative to said base member, two bearing members in contact with said strip at points spaced from each other and from said one point longitudinally of said strip, said bearing members being so arranged as to be capable in conjunction with said means to produce a moment tending to bend said strip transversely and oppositely to its bowed section, two thermo-expansion means each interposed between one of said bearing members and said base member for causing said bearing members to increase and decrease the bending force on said strip upon a rise in temperature, said thermo-expansion means being so dimensioned in relation to each other that the increase in said moment produced by one thermo-expansion means under any variation of temperature is substantially compensated for by the decrease in said moment produced by the other thermo-expansion means under the same variation of temperature, and means for producing a difference in temperature between the two thermo-expansion means whereby to cause the strip to suddenly change its curvature.
  • An electrical switch device comprising a base member, a bowed-section spring strip, means for rigidly supporting one point of said strip relative to said base member, two bearing members in contact with said strip at points spaced from each other and from said one point longitudinally of said strip, said bearing members being so ar-- ranged as to be capable in conjunction with said means to produce a moment tending to bend said strip transversely and oppositely to its bowed section, two thermo-expansion means each interposed between one of said bearing members and said base member for causing said bearing members to increase and decrease the bending force on said strip upon a rise in temperature, said thermo-expansion means being so dimensioned in relation to each other that the increase in said moment produced by one thermo-expansion means under any variation of temperature is substantially compensated for by the decrease in said moment produced by the other thermo-expansion means under the same variation of temperature, means for producing a difference in temperature between the two thermo-expansion means whereby to cause the strip to suddenly change its curvature, a movable switch contact carried
  • a thermal switch device comprising a base member. a bowed-cross-section spring strip fixed to said base member at one point, a first bearing constructed to act on said strip at a bearing point spaced from said one point to urge the strip outwardly of its curvature and substantially normally to the central tangential plane thereof, a second bearing constructed to act upon the convex side of the strip at a second bearing point intermediate said one point and said first bearing point in a direction substantially opposite to the action of said first bearing, first thermo-expansion means for moving said first bearing in its direction of action in response to variations of temperature, second thermo-expansion means for moving said second bearing in the same direction in response to similar variations in temperature, said two thermo-expansion means being so dimensioned that the relative alignment of said three points is substantially unaffected by any common variation of the temperatures of said two thermo-expansion means, and means for producing a temperature difference between said two thermo-expansion means and thereby causing the strip to flex suddenly adjacent said second bearing.
  • a thermal switch device comprising a base member, a bowed-cross-section spring strip fixed to said base member at one point, a first bearing constructed to act on said strip at a bearing point spaced from said one point to urge the strip outwardly of its curvature and substantially normally to the central tangential plane thereof, a second bearing constructed to act upon the convex side of the strip at a second bearing point intermediate said one point and said first bearing point in a direction substantially opposite to the action of said first bearing, first thermo-expansion means for moving said first bearing in its direction of action in response to variations of temperature, second thermo-expansion means for moving said second bearing in the same direction in response to similar variations in temperature, said two thermo-expansion means being so dimensioned that the relative alignment of said three points is substantially unaffected by any common variation oi the temperatures of said two thermo-expansion means, and electric heating means associated with one of said thermoexpansion means for producing a temperature difierence between said two thermo-expansion means and thereby causing the strip to
  • a thermal switch device comprising a base member, a bowed-cross-section spring strip fixed to said base member at one point, a first bearing constructed to act on said strip at a bearing point spaced from said one point to urge the strip outwardly of its curvature and substantially normally to the central tangential plane thereof.
  • a second bearing constructed to act upon the convex side of the strip at a second bearing point intermediate said one point and said first bearing point in a direction substantially opposite to the action of said first bearing, a bimetallic element for moving said first bearing in its direction of action in response to variations of temperature, a second bimetallic element for moving said second bearing in the same direction in response to similar variations in temperature, said two bimetallic elements being so dimensioned that the relative I alignment of said three points is substantially unafiected by any common variation of the temperatures or said two bimetallic elements and an electric heating resistance associated with one of said bimetallic elements for producing a temperature diil'erence between said two bimetallic elements and thereby causing the strip to suddenly change its curvature adjacent said second bearing at predetermined values or the temperature difi'erence between said two bimetallic elements.
  • a time switch device comprising a base membet, a bowed-cross-section spring strip fixed to ,said base member at one point, a first bearing constructed to act on said strip at a bearing point spaced from said one point to urge the strip outwardly of its curvature and substantially normally to the central tangential plane thereof, a second bearing constructed to act upon the convex side of the strip at a second bearing point intermediate said one point and said first bearing P int in a direction substantially opposite to the action of said first bearing, a first bimetallic strip for resiliently moving said first bearing in its direction of action in response to variations of temperature, a second bimetallic strip for moving said second bearing in the same direction in response to similar variations in temperature, said two bimetallic strips being so dimensioned that the relative alignment of said three points is substantially unaiiected by any common variation of the temperatures of said two bimetallic strips and electric heating means associated with said first bimetallic strip for individually heating said first bimetallic strip and thereby causing the bowedsection strip to flex
  • An electrical switch device comprising a base member, a bowed-cross-section spring strip fixed to said base member at one point, a first bearing constructed to act on said strip at a bearing point spaced from said one point to urge the strip outwardly of its curvature and substantially normally to the central tangential plane thereof, a second bearing constructed to act upon the convex side of the strip at a second bearing point intermediate said one point and said first bearing point in a direction substantially opposite to the action of said first bearing, a first bimetallic strip for resiliently moving said first bearing in its direction of action in response to variations of temperature, a second bimetallic strip for moving said second bearing in the same direction in response to similar variations in temperature, said two bimetallic strips being so dimensioned that the relative alignment of saidthree points is substantially unaffected by any common variation of the temperatures of said two bimetallic strips, electric heating means associated with said first bimetallic strip for individually heating said I first bimetallic strip and thereby causing the bowed-section strip to fiex suddenly adjacent said second bearing after a
  • An electrical switch device comprising a base member, a bowed-cross-section spring strip fixed to said base member at one point, a first bearing constructed to act on said strip at a bearing point spaced from said one point to urge the strip outwardly of its curvature and substantially normally to the central tangential plane thereof, a second bearing constructed to act upon the convex side of the strip at a second bearing point intermediate said one point and said first bearing point in a direction substantially opposite to the action of said first bearing, first thermo-expansion means for moving said first bearing in its direction of action in response to variations of temperature, a second thermo-expansion means for moving said second bearing in the same direction in response to variations in temperature, said two thermo-expansion means being so dimensioned that the relative alignment of said three points is substantially unaffected by any common variation of the temperatures of said 7 ing a temperature diflerence between said two file of this patent:
  • thermo-expansion means and thereby causing the strip to suddenly change its curvature adjacent said second bearing, a movable switch contact operatively connected to said strip for operation by the sudden change of curvature of the strip, a second switch contact for co-cperation with said movable contact, and thermo-expansive means interposed between said base and said second contact and so dimensioned as to cause said second contact to substantially follow the movements of said movable contact due to the simultaneous movement of said first and second bearings under variations of ambient temperature.

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  • Thermally Actuated Switches (AREA)
US64305A 1947-12-10 1948-12-09 Switch Expired - Lifetime US2574869A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB32538/47A GB647653A (en) 1947-12-10 1947-12-10 Improvements in snap-action thermal switches

Publications (1)

Publication Number Publication Date
US2574869A true US2574869A (en) 1951-11-13

Family

ID=10340132

Family Applications (1)

Application Number Title Priority Date Filing Date
US64305A Expired - Lifetime US2574869A (en) 1947-12-10 1948-12-09 Switch

Country Status (5)

Country Link
US (1) US2574869A (it)
BE (1) BE486218A (it)
FR (2) FR976357A (it)
GB (1) GB647653A (it)
NL (1) NL143732B (it)

Cited By (26)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2649520A (en) * 1951-05-24 1953-08-18 Jack & Heintz Prec Ind Inc Electrical switch
US2664481A (en) * 1951-11-14 1953-12-29 Harry A Pearl Thermal relay and constant gap spacer
US2697152A (en) * 1952-07-21 1954-12-14 Vernard Soper Thermal interrupter
DE959837C (de) * 1952-06-12 1957-03-14 Ellenberger & Poensgen Anwendung eines Bimetallschalters als Zeitrelais
US2845274A (en) * 1955-09-01 1958-07-29 Hardinge Brothers Inc Feed chucks
US2846547A (en) * 1955-09-01 1958-08-05 Telephone Mfg Co Ltd Electric control making devices
US2859306A (en) * 1957-01-10 1958-11-04 Curtiss Wright Corp Thermal time delay relay
US2866648A (en) * 1955-10-25 1958-12-30 Hardinge Brothers Inc Springs for feed chucks
DE971628C (de) * 1953-04-22 1959-03-05 Mechanical Products Inc Elektrischer Selbstschalter
US2990566A (en) * 1958-07-10 1961-07-04 New Castle Products Inc Trolley cushioning and holding means for suspended closures
US3016433A (en) * 1960-01-22 1962-01-09 Burroughs Corp Snap action device
US3052780A (en) * 1960-10-28 1962-09-04 Tung Sol Electric Inc Snap action device
US3067301A (en) * 1960-02-26 1962-12-04 Yamamoto Mititaka Tumbler switches
US3174017A (en) * 1961-08-02 1965-03-16 American Thermostat Corp Adjustable thermostat with overriding control
US3256406A (en) * 1963-04-25 1966-06-14 Ideal Corp Single-curved vane-type thermally actuated switch
US3289158A (en) * 1963-05-10 1966-11-29 Clarence S Olson Turn signal warning device
US3533039A (en) * 1969-04-14 1970-10-06 Hold Heet Products Corp Thermostatic switch and safety circuit therefor
US3568120A (en) * 1969-09-15 1971-03-02 Robertshaw Controls Co Heatmotor operator
US3600537A (en) * 1969-04-15 1971-08-17 Mechanical Enterprises Inc Switch
US3624579A (en) * 1970-09-23 1971-11-30 Honeywell Inc Anticipating thermostat
US3962664A (en) * 1975-08-25 1976-06-08 Texas Instruments Incorporated Current protector
US4090163A (en) * 1974-08-06 1978-05-16 Robertshaw Controls Company Elongated snap-acting bimetal element
US4346272A (en) * 1980-04-18 1982-08-24 General Electric Company Control device and method of operating
US20050128043A1 (en) * 2001-07-10 2005-06-16 Jeffrey Ying Controllable electronic switch
US20050207081A1 (en) * 2001-07-10 2005-09-22 Jeffrey Ying System for remotely controlling energy distribution at local sites
US20100102918A1 (en) * 2007-02-01 2010-04-29 Siemens Aktiengesellschaft Electromechanical swithcing device for protecting electrical wires and/or consumers and use of a thermal coupling in an electromechanical switching device

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1581124A (en) * 1924-08-22 1926-04-20 Herbert S Humphrey Thermostat
US1900647A (en) * 1931-08-17 1933-03-07 Ernest A Hoopes Electric switch
US2054558A (en) * 1934-05-11 1936-09-15 Emerson Electric Mfg Co Thermostat
US2208432A (en) * 1935-12-10 1940-07-16 Seaboard Commercial Corp Electric flatiron
US2399123A (en) * 1943-09-15 1946-04-23 Dominion Electrical Mfg Inc Quick-action mechanism

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1581124A (en) * 1924-08-22 1926-04-20 Herbert S Humphrey Thermostat
US1900647A (en) * 1931-08-17 1933-03-07 Ernest A Hoopes Electric switch
US2054558A (en) * 1934-05-11 1936-09-15 Emerson Electric Mfg Co Thermostat
US2208432A (en) * 1935-12-10 1940-07-16 Seaboard Commercial Corp Electric flatiron
US2399123A (en) * 1943-09-15 1946-04-23 Dominion Electrical Mfg Inc Quick-action mechanism

Cited By (39)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2649520A (en) * 1951-05-24 1953-08-18 Jack & Heintz Prec Ind Inc Electrical switch
US2664481A (en) * 1951-11-14 1953-12-29 Harry A Pearl Thermal relay and constant gap spacer
DE959837C (de) * 1952-06-12 1957-03-14 Ellenberger & Poensgen Anwendung eines Bimetallschalters als Zeitrelais
US2697152A (en) * 1952-07-21 1954-12-14 Vernard Soper Thermal interrupter
DE971628C (de) * 1953-04-22 1959-03-05 Mechanical Products Inc Elektrischer Selbstschalter
US2845274A (en) * 1955-09-01 1958-07-29 Hardinge Brothers Inc Feed chucks
US2846547A (en) * 1955-09-01 1958-08-05 Telephone Mfg Co Ltd Electric control making devices
US2866648A (en) * 1955-10-25 1958-12-30 Hardinge Brothers Inc Springs for feed chucks
US2859306A (en) * 1957-01-10 1958-11-04 Curtiss Wright Corp Thermal time delay relay
US2990566A (en) * 1958-07-10 1961-07-04 New Castle Products Inc Trolley cushioning and holding means for suspended closures
US3016433A (en) * 1960-01-22 1962-01-09 Burroughs Corp Snap action device
US3067301A (en) * 1960-02-26 1962-12-04 Yamamoto Mititaka Tumbler switches
US3052780A (en) * 1960-10-28 1962-09-04 Tung Sol Electric Inc Snap action device
US3174017A (en) * 1961-08-02 1965-03-16 American Thermostat Corp Adjustable thermostat with overriding control
US3256406A (en) * 1963-04-25 1966-06-14 Ideal Corp Single-curved vane-type thermally actuated switch
US3289158A (en) * 1963-05-10 1966-11-29 Clarence S Olson Turn signal warning device
US3533039A (en) * 1969-04-14 1970-10-06 Hold Heet Products Corp Thermostatic switch and safety circuit therefor
US3600537A (en) * 1969-04-15 1971-08-17 Mechanical Enterprises Inc Switch
US3568120A (en) * 1969-09-15 1971-03-02 Robertshaw Controls Co Heatmotor operator
US3624579A (en) * 1970-09-23 1971-11-30 Honeywell Inc Anticipating thermostat
US4090163A (en) * 1974-08-06 1978-05-16 Robertshaw Controls Company Elongated snap-acting bimetal element
US3962664A (en) * 1975-08-25 1976-06-08 Texas Instruments Incorporated Current protector
US4346272A (en) * 1980-04-18 1982-08-24 General Electric Company Control device and method of operating
US20080186126A1 (en) * 2001-07-10 2008-08-07 Yingco Electronic Inc. Controllable Electronic Switch
US7688175B2 (en) 2001-07-10 2010-03-30 I/O Controls Corporation Controllable electronic switch
US20060064205A1 (en) * 2001-07-10 2006-03-23 Jeffrey Ying Remotely controllable wireless energy control unit
US7265652B2 (en) * 2001-07-10 2007-09-04 Yingco Electronic Inc. Controllable electronic switch
US7324876B2 (en) 2001-07-10 2008-01-29 Yingco Electronic Inc. System for remotely controlling energy distribution at local sites
US20050128043A1 (en) * 2001-07-10 2005-06-16 Jeffrey Ying Controllable electronic switch
US20100013592A1 (en) * 2001-07-10 2010-01-21 Yingco Electronic Inc. Controllable electronic switch
US20050207081A1 (en) * 2001-07-10 2005-09-22 Jeffrey Ying System for remotely controlling energy distribution at local sites
US7693610B2 (en) 2001-07-10 2010-04-06 Yingco Electronic Inc. Remotely controllable wireless energy control unit
US10074498B2 (en) 2001-07-10 2018-09-11 I/O Controls Corporation Controllable electronic switch
US7925388B2 (en) 2001-07-10 2011-04-12 Yingco Electronics, Inc. Remotely controllable wireless energy control unit
US7961073B2 (en) 2001-07-10 2011-06-14 Yingco Electronic Inc. Controllable electronic switch
US20120092122A1 (en) * 2001-07-10 2012-04-19 Yingco Electronic Inc. Controllable electronic switch
US8981891B2 (en) * 2001-07-10 2015-03-17 I/O Controls Corporation Controllable electronic switch
US20150255238A1 (en) * 2001-07-10 2015-09-10 I/O Controls Corporation Controllable electronic switch
US20100102918A1 (en) * 2007-02-01 2010-04-29 Siemens Aktiengesellschaft Electromechanical swithcing device for protecting electrical wires and/or consumers and use of a thermal coupling in an electromechanical switching device

Also Published As

Publication number Publication date
BE486218A (it)
GB647653A (en) 1950-12-20
NL143732B (nl)
FR976357A (fr) 1951-03-16
FR276357A (it)

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