US2824194A - Switch structures - Google Patents
Switch structures Download PDFInfo
- Publication number
- US2824194A US2824194A US601501A US60150156A US2824194A US 2824194 A US2824194 A US 2824194A US 601501 A US601501 A US 601501A US 60150156 A US60150156 A US 60150156A US 2824194 A US2824194 A US 2824194A
- Authority
- US
- United States
- Prior art keywords
- contacts
- contact member
- bridging
- spaced
- electrical
- 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
Links
Images
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
- H01H37/00—Thermally-actuated switches
- H01H37/02—Details
- H01H37/32—Thermally-sensitive members
- H01H37/52—Thermally-sensitive members actuated due to deflection of bimetallic element
- H01H37/54—Thermally-sensitive members actuated due to deflection of bimetallic element wherein the bimetallic element is inherently snap acting
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
- H01H1/00—Contacts
- H01H1/12—Contacts characterised by the manner in which co-operating contacts engage
- H01H1/14—Contacts characterised by the manner in which co-operating contacts engage by abutting
- H01H1/20—Bridging contacts
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
- H01H37/00—Thermally-actuated switches
- H01H37/02—Details
- H01H37/32—Thermally-sensitive members
- H01H37/52—Thermally-sensitive members actuated due to deflection of bimetallic element
- H01H37/54—Thermally-sensitive members actuated due to deflection of bimetallic element wherein the bimetallic element is inherently snap acting
- H01H2037/549—Details of movement transmission between bimetallic snap element and contact
Definitions
- an object of this invention is to provide an improved electrical device and/ or an improved structural member for an electrical device whereby deleterious effects due to electrical arcing are either prevented or substantially lessened.
- Another object of this invention is to provide an improved electrical device by which the intensity of the arcing across its electrical contacts is kept to a minimum.
- A; further object of this invention is to provide an electrical device having spaced contacts and a bridging contact member whereby the pressure exerted by the bridging contact member against each of spaced contacts remains; substantially equal with changes in the effective relative heights of the spaced contacts.
- '-A further object of this invention is to provide an electrical device having spaced contacts and a bridging contact member whereby separation of the bridging contact mem ber from all of the spaced contacts is accomplished simultane'ously.
- Another object of this invention is to provide an improvedcasing or structural member for an electrical device and/or an improved electrical device embodying such a structural member whereby an unintended substantial increasejin the-conductivity along a surfaceof the structuralmember otherwise intendedto be nonconductive is prevented or effectively counteracted.
- a furtherobject of this invention is to provide such a structural member and/orsuch an electrical device whereby certain deleterious and objectionable effects of an elec- Fig. 2 is a sectional view taken along line 2-2 of Fig. 1
- Fig. 3 is a plan view of the cup-shaped member included in Fig. 1 and against one end of which seats a spring for biasing the contacts toward closed position;
- Fig. 4 is a plan view of the bridging contact member included in Figs. 1 and 2;
- Fig. 5 is a perspective view of the transfer member included in Figs. 1 and 2;
- Fig. 6 is a view similar to Fig. l but showing the con tacts of the device in open position;
- Fig. 7 is a sectional view taken along line 77 in Fig. l;
- Fig. 8 is a view similar to Fig. 7 but showing the contacts of the device in open position.
- Electrical switch 10 includes structural means in the form or" a casing 12 formed of electrically insulating material such as one of the customary molded plastics.
- a pair of terminals 13, 14 are supported by easing member 12 in any suitable manner.
- casing member 12 may be molded about these terminals.
- Each of terminals 13, 14 leads to the exterior of the casing member whereby it may be connected to one side of a source of electrical current.
- Terminals 13 and 14 provide contacts or contact-forming portions 15 and 16, respectively.
- Contacts 15 and 16 may be provided with layers or portions 17 and 18, respectively, which are formed of a material having a high electrical conductivity such as silver and which arev suitably bonded to the remainder of these respective contacts.
- Terminals 13 and 14, except for layers or portions 17 and 18, may be formed of a suitably electrically conductive material such as brass, Monel or copper.
- a bridging contact member 20 made of, for example, brass, Monel or copper, is disposed adjacent contacts 15 and 16.
- the contact-forming surface of contact member 20 which cooperates with the adjacent surface of contacts 15 and 16 is formed by a layer or portion 21 of silver or other contact alloy which is suitably bonded to the remainder of contact member 20.
- Fig. 1 is a sectional view of an electrical device embodying this invention and showing the contactsof this device in. closed position;
- convexly curved surface 25 which is associated with a convexly curved surface 25 provided by the bottom of a generally cupshaped member 26. At each end of concavely curved surface 24 is located a corner 27, 27. As is apparent from Figs. 1 and 3 convexly curved surface 25 is formed on a greater radius of curvature than depression 24 with the result that surface 25 engages bridging contact member 20 at corners 27, 27. 7
- a compression spring 30 is seated in cupshaped member 26 and the other end thereof is seated in a socket 31 provided by casing member 12. Accordingly, spring 30 resiliently biases contact or contact member 20 against contacts 15 and 16. It will be noted that spring 30 is confined only at its ends, and that it is laterally displaceable in socket 31 whereby it is free to seek an adjusted position if so constrained due to lateral displacement of bridging member 20. Also it will be noted that each end of spring 30 is formed so that the respective end turns of the coil lie substantially perpendicular to the opposite directions of flexure of the spring during operation of the switch 10. Since the portion of cup-shaped member 26 against which spring 30 seats is flat, it is clear that member 26 is resiliently biased by this spring against pivotal movement.
- the open end of casing member 12 may be closed by a metallic, electrically conductive, cup member 35 which may be spun or otherwise turned in about its periphery at 36 to. secure it to casing member 12
- a thermally responsive, snap-acting element or disc 33 Disposed within cup 35 and adjacent the open end of casing member 12 is a thermally responsive, snap-acting element or disc 33.
- This disc ma, be of the bimetallic type shown and described in. United States Patent No. 1,448,240 to J. A. Spencer, issued March 13', 1923 Disc 38 is shown in Figs. 1 and 7 in a downwardly bowed condition. In response to an ambient temperature change this disc is effective to snap to the upwardly bowed condition or shape shown in Figs. 2 and 8.
- One end 42 of transfer slide 40 is disposed in abutment with a central portion of disc 38, and the other end thereof provides, a flat surface 43 disposed adjacent bridging contact memberlf).
- contact member 20 provides opposed recesses 45, 45 with which-transfer member 40 interfits.
- Bridging contact member 24 further provides a convexly curved surface 44 for cooperation with end surface 43. of transfer member 40.
- End surface 43 of transfer member 40 is engageable with convexly curved surface 44 substantially midway between spaced contacts 15 and 16.
- Surface 44. is convexly curved along a plane intersecting bridging contact member 20 and spaced contacts 15, 16. It will be apparent from Figs. 1 and 6 that corners 27, 27 engage convexly curved surface 25 one at each side of and adjacent to a vertical plane passing through the center or asis of curvature of surface 25 and through the mutually engaged portions of surfaces 43 and 44.
- convexly curved surface 44 lies closely adjacent a plane which engages the surfaces of bridging contact member 20 that respectively engage contacts 15 and'16, and which plane lies normal to the opposite directions of movement of transfer member 40.
- corners 27, 27 and'convexly curved surface 44 provides a number of the features of thisinvention. Ifthe surface of oneof the contacts Her 16 should build-up more than the other or if the effective height of either of these contact surfaces should change relative to the other for any other reason, corners 27, 27 in association with surface 44 would permit bridging contact member 20 to pivot relative to cup-shaped member 26 during movement of'member 20 to the position shown in Figs. 1 and 7. That is, as bridging member 20 is moved downwardly to the position shown in Figs.
- bridging member 20 presses with equal force against each of spaced contacts 15, 16 is that within the practical limits to which bridging member 29 is likely to pivot relative to cup-shaped member 26, both of corners 27, 27 will always engage convexly curved surface 25 closely. adjacent to and one on each side of the above-mentioned verticalplane which passes. through the axis or center of curvature of surface 25 and through the mutually engaged portions of surfaces 43 and 44. It follows that, thereby, the total pressing force exerted by bridging contact member 20 willbe equally divided between spaced contacts 15, 16- regardless of pivotal movement of contact member 20.
- cup shapedzmember 26 is resiliently biased against pivotalmovement: by, spring Y30 and secondly because spring: 30,-- due tothedisclosed exemplary arrangementwhereby'it is laterally displaceable in'socket 31 and is unconfinedbetweenits ends, permits this cup-shaped member to be laterally-displaced without a tendency which would othen wise result toward pivotal movement of member-zflwhenf disengaged; from spaced contacts 15, 16; Obviously, if
- pivotal movement of bridging contact member 201 will: result whereby equal contact pressures and simultaneous COD-e" tact separation will continue to be maintained.
- the arcing may extend into the region immediately adjacent and surrounding -the-coacting surfaces of electrical contacts; in the case of the exemplary embodiment shown in the drawings, adjacent and surrounding the coacting surfaces of-contact member 20 and contacts 15 and 16.
- a comparatively high heat is developed by theatre, which heat may be effective to vaporize'the material of which the contacts are formed.
- the contact material vapon'zes, it emanates from the region immediately adjacent and surrounding the coacting surfaces of the contacts. The particles of this emanation travel along a substantially rectilinear path and are deposited on the structure of the device adjacent and exposed to this region.
- an unintended electrically conductive path might be set up leading from any one of contacts 15, 16 or 20, along the interior surface of casing member 12 to cup 35 which would otherwise be electrically insulated from each of these contacts.
- the internal surface of casing member 12 provides two portions indicated generally by reference numerals 46 and 47, respectively.
- Each of surface portions 46 and 47 in this embodiment is continuous about the inner periphery of casing member 12 and is exposed to the above-mentioned region immediately adjacent and surrounding the coacting surfaces of the contacts.
- the surface portion of casing 12 which is intermediate surface portions 46 and 47 is configured to provide a projection 48. Adjacent projection 48 this intermediate surface portion provides a recess 49 whereby projection 48 lies between recess 49 and the above-mentioned region.
- contact as used throughout this specification is intended to encompass any means which is cooperative with another means to provide an electrically conductive path from one to the other and between and/ v first surface convexly curved along a plane intersecting said bridging contact member and said spaced contacts,
- a transfer member having a flat surface movable against said convexly curved surface substantially midway between said spaced contacts to move said bridging contact member away from said spaced contacts in one of said opposite directions, an additional member providing a third surface convexly curved about an axis, said axis and the mutually engaged portions of said first and flat surfaces lying in a common plane, means resiliently biasing said additional member against pivotal movement and in the other of said opposite directions, and said bridging contact member providing two spaced corners engaging said third surface, one at each side of and adjacent to said common plane, whereby said bridging contact member presses with substantially equal force on each of said spaced contacts when engaged therewith and is prevented from pivotal movement relative to said third surface only when separated from said spaced contacts.
- a pair of spaced electrical contacts a bridging, electrical contact member movable in opposite directions into and out of engagement with said spaced contacts, said bridging contact member having a first surface convexly curved along a plane intersect ing said bridging contact member and said spaced con tacts, a transfer member having 'a flat surface movable against said convexly curved surface substantially midway between said spaced contacts to move said bridging contact member away from said spaced contacts in one of said opposite directions, an additional member providing a third surface convexly curved about an axis, said axis and the mutually engaged portions of said first and flat surfaces lying in a common plane, means permitting lateral displacement of said bridging contact member and resiliently biasing said additional member in the other of said opposite directions, and said bridging contact member providing two spaced corners engaging said third surface, one at each side of and adjacent to said common plane, whereby said bridging contact member presses with substantially equal force on each of said spaced contacts when engaged therewith and
- a pair of electrical contacts cooperable with each other to make and break an electrical circuit
- a hollow casing member formed of electrically insulating material and surrounding said contacts; the interior surface of said casing being continuous about its periphery and, in cross-section, leading from a point adjacent the region immediately surrounding said contacts along a first length exposed to said region, then leading in a generally reverse direction behind the adjacent part of said first length from said region, and then leading in another generally reverse direction to extend along a second length and in substantially the same direction as said first length; and at least a portion of said second length being exposed to said region; whereby a peripherally continuous, interior surface area of said casing is shielded from said region.
Landscapes
- Physics & Mathematics (AREA)
- Thermal Sciences (AREA)
- Manufacture Of Switches (AREA)
- Switch Cases, Indication, And Locking (AREA)
- Arc-Extinguishing Devices That Are Switches (AREA)
- Thermally Actuated Switches (AREA)
- Contacts (AREA)
Priority Applications (5)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US601501A US2824194A (en) | 1956-08-01 | 1956-08-01 | Switch structures |
GB16163/57A GB866597A (en) | 1956-08-01 | 1957-05-21 | Improvements in or relating to electrical switches |
FR1175864D FR1175864A (fr) | 1956-08-01 | 1957-05-31 | Interrupteur |
DEM34788A DE1088131B (de) | 1956-08-01 | 1957-07-16 | Elektrischer Schalter mit zwei stationaeren Kontaktstuecken |
DEM34789A DE1160528B (de) | 1956-08-01 | 1957-07-16 | Elektrischer Schalter mit Kriechstromschutz |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US601501A US2824194A (en) | 1956-08-01 | 1956-08-01 | Switch structures |
Publications (1)
Publication Number | Publication Date |
---|---|
US2824194A true US2824194A (en) | 1958-02-18 |
Family
ID=24407725
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US601501A Expired - Lifetime US2824194A (en) | 1956-08-01 | 1956-08-01 | Switch structures |
Country Status (4)
Country | Link |
---|---|
US (1) | US2824194A (de) |
DE (2) | DE1160528B (de) |
FR (1) | FR1175864A (de) |
GB (1) | GB866597A (de) |
Cited By (15)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2907851A (en) * | 1958-05-21 | 1959-10-06 | Texas Instruments Inc | Electrical switch structures |
US3038040A (en) * | 1957-10-14 | 1962-06-05 | Int Register Co | Timing mechanism |
US3059080A (en) * | 1959-09-17 | 1962-10-16 | Penn Controls | Flame detector |
US3091121A (en) * | 1958-10-27 | 1963-05-28 | Texas Instruments Inc | Thermostatic controls |
US3164701A (en) * | 1961-05-29 | 1965-01-05 | Texas Instruments Inc | Method of assembling thermostatic switches |
US3258567A (en) * | 1964-05-29 | 1966-06-28 | Elmwood Sensors | Thermostat and reset therefor |
US3268700A (en) * | 1964-06-18 | 1966-08-23 | Illinois Tool Works | Snap acting trigger switch |
US3283097A (en) * | 1962-06-06 | 1966-11-01 | White Sales Corp Graham | Thermo-electric timer |
US3852697A (en) * | 1973-07-11 | 1974-12-03 | Therm O Disc Inc | Bimetal snap disc |
US4317100A (en) * | 1980-10-29 | 1982-02-23 | Texas Instruments Incorporated | Readily mountable thermostat |
US4365228A (en) * | 1981-04-03 | 1982-12-21 | Robertshaw Controls Company | Thermostat construction having a one piece plunger with a wing-like section and method of making the same |
US4696579A (en) * | 1984-10-24 | 1987-09-29 | Texas Instruments Incorporated | Thermostat |
DE3740873A1 (de) * | 1986-12-18 | 1988-06-30 | Electrovac | Verfahren zur justierung eines thermischen schalters |
US4827096A (en) * | 1985-11-05 | 1989-05-02 | Bruno Martinetti | Universal switch with integral contact tabs |
US5629506A (en) * | 1994-06-15 | 1997-05-13 | General Electric Company | Low voltage AC contactor including high recovery voltage gas system |
Families Citing this family (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
AT349794B (de) * | 1976-06-25 | 1979-04-25 | Electrovac | Thermischer schalter |
Citations (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US1988369A (en) * | 1931-11-12 | 1935-01-15 | Locke Insulator Corp | Radio interferenceproof insulator |
US2094199A (en) * | 1934-07-25 | 1937-09-28 | Gen Motors Corp | Switch |
US2392342A (en) * | 1943-01-18 | 1946-01-08 | Line Material Co | Combined spark gap and insulator |
US2570610A (en) * | 1947-08-23 | 1951-10-09 | Allis Chalmers Mfg Co | Gas blast circuit breaker with trap for products of arcing |
US2650971A (en) * | 1950-06-08 | 1953-09-01 | Allen Bradley Co | Electrical switch |
US2714643A (en) * | 1952-12-27 | 1955-08-02 | Charles W Mitchell | Fire detecting unit |
US2740869A (en) * | 1953-07-20 | 1956-04-03 | Jennings Radio Mfg Corp | Vacuum switch |
US2753422A (en) * | 1953-03-11 | 1956-07-03 | Stevens Mfg Co Inc | Thermostatic switch |
Family Cites Families (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US1261456A (en) * | 1917-06-22 | 1918-04-02 | Hart & Hegeman Mfg Co | Switch. |
AT105577B (de) * | 1925-01-16 | 1927-02-10 | Aeg Union Elek Wien | Schaltapparate. |
DE576319C (de) * | 1927-10-22 | 1933-05-10 | Siemens Schuckertwerke Akt Ges | Schalter mit Loeschung des Lichtbogens durch Druckluft |
DE596573C (de) * | 1928-08-01 | 1934-05-05 | Siemens Schuckertwerke Akt Ges | Druckluftschalter mit Mehrfachunterbrechung |
DE555830C (de) * | 1928-09-20 | 1932-08-01 | Sigwart Ruppel Dipl Ing | Schalter mit Lichtbogenloeschung durch stroemendes Druckgas |
US1992923A (en) * | 1933-05-22 | 1935-02-26 | Abraham S Pinkus | Switch |
DE670720C (de) * | 1934-09-06 | 1939-01-25 | Frida Strauss Geb Ruppel | Gasschalter |
US2712580A (en) * | 1952-04-26 | 1955-07-05 | Gen Electric | Contact making and breaking device |
DE1700883U (de) * | 1952-06-28 | 1955-06-23 | Kloeckner Moeller Elektrizit | Kontaktanordnung fuer leistungsschalter. |
-
1956
- 1956-08-01 US US601501A patent/US2824194A/en not_active Expired - Lifetime
-
1957
- 1957-05-21 GB GB16163/57A patent/GB866597A/en not_active Expired
- 1957-05-31 FR FR1175864D patent/FR1175864A/fr not_active Expired
- 1957-07-16 DE DEM34789A patent/DE1160528B/de active Pending
- 1957-07-16 DE DEM34788A patent/DE1088131B/de active Pending
Patent Citations (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US1988369A (en) * | 1931-11-12 | 1935-01-15 | Locke Insulator Corp | Radio interferenceproof insulator |
US2094199A (en) * | 1934-07-25 | 1937-09-28 | Gen Motors Corp | Switch |
US2392342A (en) * | 1943-01-18 | 1946-01-08 | Line Material Co | Combined spark gap and insulator |
US2570610A (en) * | 1947-08-23 | 1951-10-09 | Allis Chalmers Mfg Co | Gas blast circuit breaker with trap for products of arcing |
US2650971A (en) * | 1950-06-08 | 1953-09-01 | Allen Bradley Co | Electrical switch |
US2714643A (en) * | 1952-12-27 | 1955-08-02 | Charles W Mitchell | Fire detecting unit |
US2753422A (en) * | 1953-03-11 | 1956-07-03 | Stevens Mfg Co Inc | Thermostatic switch |
US2740869A (en) * | 1953-07-20 | 1956-04-03 | Jennings Radio Mfg Corp | Vacuum switch |
Cited By (17)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3038040A (en) * | 1957-10-14 | 1962-06-05 | Int Register Co | Timing mechanism |
US2907851A (en) * | 1958-05-21 | 1959-10-06 | Texas Instruments Inc | Electrical switch structures |
US3091121A (en) * | 1958-10-27 | 1963-05-28 | Texas Instruments Inc | Thermostatic controls |
US3059080A (en) * | 1959-09-17 | 1962-10-16 | Penn Controls | Flame detector |
DE1490739B1 (de) * | 1961-05-29 | 1970-08-20 | Texas Instruments Inc | Verfahren zum Einstellen der Betaetigungsbewegung eines Thermoschnappgliedes |
US3164701A (en) * | 1961-05-29 | 1965-01-05 | Texas Instruments Inc | Method of assembling thermostatic switches |
US3283097A (en) * | 1962-06-06 | 1966-11-01 | White Sales Corp Graham | Thermo-electric timer |
US3258567A (en) * | 1964-05-29 | 1966-06-28 | Elmwood Sensors | Thermostat and reset therefor |
US3268700A (en) * | 1964-06-18 | 1966-08-23 | Illinois Tool Works | Snap acting trigger switch |
US3852697A (en) * | 1973-07-11 | 1974-12-03 | Therm O Disc Inc | Bimetal snap disc |
US4317100A (en) * | 1980-10-29 | 1982-02-23 | Texas Instruments Incorporated | Readily mountable thermostat |
US4365228A (en) * | 1981-04-03 | 1982-12-21 | Robertshaw Controls Company | Thermostat construction having a one piece plunger with a wing-like section and method of making the same |
US4696579A (en) * | 1984-10-24 | 1987-09-29 | Texas Instruments Incorporated | Thermostat |
US4827096A (en) * | 1985-11-05 | 1989-05-02 | Bruno Martinetti | Universal switch with integral contact tabs |
DE3740873A1 (de) * | 1986-12-18 | 1988-06-30 | Electrovac | Verfahren zur justierung eines thermischen schalters |
DE3740873C2 (de) * | 1986-12-18 | 1999-10-07 | Electrovac | Verfahren zur Justierung eines thermischen Schalters |
US5629506A (en) * | 1994-06-15 | 1997-05-13 | General Electric Company | Low voltage AC contactor including high recovery voltage gas system |
Also Published As
Publication number | Publication date |
---|---|
GB866597A (en) | 1961-04-26 |
FR1175864A (fr) | 1959-04-02 |
DE1160528B (de) | 1964-01-02 |
DE1088131B (de) | 1960-09-01 |
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