US3781501A - Single pole electric switch with contacts convertible from normally open to normally closed and vice versa - Google Patents

Single pole electric switch with contacts convertible from normally open to normally closed and vice versa Download PDF

Info

Publication number
US3781501A
US3781501A US00313844A US3781501DA US3781501A US 3781501 A US3781501 A US 3781501A US 00313844 A US00313844 A US 00313844A US 3781501D A US3781501D A US 3781501DA US 3781501 A US3781501 A US 3781501A
Authority
US
United States
Prior art keywords
bar
contacts
switch
positions
lid member
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
US00313844A
Other languages
English (en)
Inventor
G Borghetti
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.)
Telemeccanica Elettrica
Original Assignee
Telemeccanica Elettrica
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 Telemeccanica Elettrica filed Critical Telemeccanica Elettrica
Application granted granted Critical
Publication of US3781501A publication Critical patent/US3781501A/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
    • H01H50/00—Details of electromagnetic relays
    • H01H50/54—Contact arrangements
    • H01H50/546—Contact arrangements for contactors having bridging contacts
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
    • H01H11/00—Apparatus or processes specially adapted for the manufacture of electric switches
    • H01H11/0006—Apparatus or processes specially adapted for the manufacture of electric switches for converting electric switches
    • H01H11/0012—Apparatus or processes specially adapted for the manufacture of electric switches for converting electric switches for converting normally open to normally closed switches and vice versa
    • 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
    • H01H1/2008—Facilitate mounting or replacing contact bridge and pressure spring on carrier

Definitions

  • ABSTRACT [21] 313844 An electric switch having fixed contacts on a housing and having an invertible bar slidable therein, the bar [30] F i Application priority Data carrying a contact bridging arm with contacts engage- D e c 22 1971 Italy 32766 A /71 able with the fixed contacts, a contact pressure applying spring acting between the bar and the arm and a [52] CL U zoo/166 BC ZOO/165 return spring acting between the bar and an abutting [51] Int. Cl. 1101b l/34 element mounted off-center on an invertible and [58] Field of Search [6 BC movable lid for the housing.
  • the contacts are normally open and in the inverted position thereof, the contacts are normally [56] References Cited closed, the contact position being indicated by sym- UNITED STATES PATENTS bols alternately exposed depending on the lid position.
  • Switches of the type to which the invention relates are often demanded by the users both because the associated circuit can be modified by converting its own electric condition and because it is convenient, for example, to have a stored stock of switches which can be used as required, as normally open or normally closed contact switches.
  • the stored stock comprises switches of the type in which the contacts are always normally closed and others of the type in which the contacts are always normally open, double inventory problems are involved.
  • the stock of one of the two types of switches may be depleted in the course of time, and the switches of the other type cannot be used to supply the demand. In the latter event, the user is then compelled to await, after a further order, the receipt of a new stock, with a consequent loss of time and, usually, he cannot utilize switches of the other type.
  • switches of the convertible contact type are available in the stock, the user can, if necessary, convert the switch to the type suitable for the required use, and at the same time, he can be sure to utilize the whole stored stock.
  • Switches of the above described type are already known in the art. In general, they comprise an operating bar or plunger slidable on guides, either by manual actuation or by the action of a machine part with which the switch is associated, a bridging arm carrying movable contact members and being secured to the operating bar and two cylindrical or helical springs, the first of which will be hereinafter called overrun spring and the second return spring.”
  • the second, or return, spring opposes the movement imparted to the operating bar
  • the first, or overrun, spring has a double function, namely that of ensuring, when the movable contact members engage the fixed contact members, a pressure sufficient to establish a good electric contact, and when the device is normally closed, prevention of the opening of the contact members for accidental causes, such as, for example, vibrations which may cause small movements of the operating bar.
  • the conversion from one condition of the contact members to the other is carried out in various ways. By way of example, reference is made to the switch described in the British Pat. No. 784,777.
  • the present invention has as one object the providing of a switch which is reliable in any working conditions and which is constructed so that difficult assembling and disassembling operations are avoided in the conversion of the condition of the contacts from normally open to normally closed or vice versa.
  • the object of the present invention is to provide a single pole, electric switch of the type which can be converted from normally open to normally closed contacts by rotating a movable assembly through 180 with respect to a fixed assembly, said fixed assembly comprising a housing, a lid, and fixed contact members, and said movable assembly comprising an operating bar slidable in said housing, said operating bar carrying a bridging arm with movable contact members, a first over-run spring and a second return spring for moving said bar.
  • the switch of the invention is characterized by an abutting element which is fixed in position with respect to the housing when the switch is in operating condition and which can be arranged in two different positions, depending on whether the contacts are normally open or normally closed. The second, or return, spring is compressed between said abutting element and said movable assembly.
  • FIG. 1 is an end, exterior view of the switch with the contacts normally open;
  • FIG. 2 is a front elevation, cross sectional view of the embodiment in FIG. 1 and is taken along the line lIII indicated in FIG. 1;
  • FIG. 3 is a longitudinal, sectional view of the embodiment in FIG. 2and is taken along the line IIIIII indicated in FIG. 2;
  • FIG. 4 is a fragmentary, longitudinal sectional view of the embodiment in FIG. 2 and is taken along the line IVIV indicated in FIG. 2;
  • FIG. 5 is a front elevation, cross sectional view, similar to FIG. 2, but showing the parts in their positions when the contacts are normally closed.
  • the electric switch of the present invention is provided with a single pole contact which can be normally open or normally closed.
  • the switch comprises a fixed assembly and a movable assembly. The latter must be rotated through 180 to carry out the change from one condition of the contacts to the other.
  • the fixed assembly comprises a housing 1, a lid 2, and fixed contact members 3, 4 having double-faced, fixed contacts.
  • Both thehousing 1 and the lid 2 may be of a thermoplastic material, such as, for example, a polycarbonate.
  • The'movable assembly comprises an operating bar 4, a bridging arm 6 carrying movable contact members 6a and 6b, a first spring 7 called an over-run spring, a second spring 8 called a return spring, and an abutting element 9 (see FIGS. 1, 2 and 3).
  • the abutting element 9 is stationary and can be arranged in two different positions, depending on whether the contacts are normally open or normally closed, FIGS. 2-4 showing the position when the contacts are normally open and FIG. 5, showing its position when the contacts are normally closed.
  • the abutting element 9 in each of said two positions, engages an end of the return spring 8.
  • the abutting element 9 is secured to and extends from the lid 2 (see FIG. 4) and is changed in position with the lid 2 when the latter is rotated by 180 in the changing from the condition of normally open contacts to that of normally closed contacts or vice versa.
  • the abutting element 9 be movable with the lid 2
  • the abutting element 9 need not be secured to the lid 2 and may, instead, be mounted on another part of the switch and be movable between the two positions described.
  • said element 9 will not be described as a part of the lid 2 but as an abutting element 9.
  • the operating bar 5 is slidable in the housing 1, in the manner described hereinafter, and is provided with two windows 10 and 11 (FIG. 3).
  • the window 10 is provided with two centering seats 12 and 13 for the ends of the return spring 8, and the window 11 is provided with one centering seat 14 for the over-run spring 7.
  • the latter in the case of normally open contacts(see FIG. 2), has one end engaging the bridging arm 6 which carries the movable contact members 6a and 6b and the arm 6 is pressed against a surface 15 at one end of the window 11.
  • the operating bar 5 also has seats or guides 35 and 36 in the form of cut-outs for assuring the correct insertion of the lid 2 in the housing 1 (see FIG. 3).
  • the housing 1 besides being provided with the seats or apertures 16 and 17 intended to receive the means for securing the lid 2 (hereinafter described), has cavities 18 and 19 for the fixed contact members 3 and 4, which extend into openings 20 and 21 to allow the necessary connections, e.g., with electric wires.
  • the housing 1 is provided with portions forming guides 22, 23 for guiding the sliding of the operating bar 5 and with a stop surface 24 (see FIG. 3.).
  • the operating bar 5 has at one end a protuberance 25 and a supporting or stop engaging surface 27 and, at the other end, a protuberance 26 and a supporting or stop engaging surface 28.
  • each of said means 29 and 30 is of elastic type.
  • Each of said means 29 and 30 is provided with two teeth, such as the teeth 31 and 32 shaped in a particular manner.
  • the teeth 31 and 32 are kept in close proximity to each other.
  • the teeth 31 and 32 flare out, causing the securing of the lid 2 to the housing 1.
  • the lid 2 is provided with a positioning tooth 37 (see FIG. 3) which will be received in the positioning cut-out 35 when the switch is in the condition of normally open contacts or will be received in the positioning cut-out 36'when the switch is in the condition of normally closed contacts.
  • the operation of the switch will now be considered with reference at first to the embodiment illustrated in FIGS. 1-4, namely, to a switch having normally open contacts.
  • the operating bar 5 (see FIG. 3) has its supporting surface 27 in contact with the stop surface 24 of the housing 1 because the return spring 8 is compressed between the abutting element 9 and the end surface of window 10, the spring 8, at one end, surrounding the centering seat 13.
  • the actuation of the switch and closing of the contacts occurs when an operator or a machine part modifies this rest condition by exerting a force on the protuberance 26 of the operating bar 5, which is pushed upward and guided by the guides 22 and 23.
  • the return spring 8 is compressed, one of its ends surrounding the centering seat 13 situated on the operating bar 5 now being moved and the other end pressing against the abutting element 9, which is stationary.
  • the overrun spring 7 remains in its initial condition until the operating bar 5, on account of its motion, brings the contacts 6a and 6 b of the bridging arm 6 into contact with the fixed contact members 3 and 4.
  • the over-run spring 7 behaves like the return spring 8, the spring 7 having one end surrounding the centering seat 14 situated on the operating bar 5 and the other end engaging the bridging arm 6 carrying the movable contact members 6a and 6b which now engage the fixed contact members 3 and 4.
  • the surface of the window 11 moves away from the bridging arm 6 which carries the movable contacts members 6a and 6b.
  • the return spring 8 and the over-run spring 7 expand, but the contact members 6a, 6b, 3 and 4 do not separate immediately because, owing to the return movement of the operating bar 5, the surface 15 of the window 1 1 does not come into immediate contact with the bridging arm 6.
  • the over-run spring 7 is already in its fully extended position, whereas the return spring 8, expanding further, brings the operating bar 5 into the position shown in FIG. 2 which corresponds to that of a switch with normally open contacts.
  • the positioning tooth 37 is always contained inside the positioning seat 35 of the operating bar itself.
  • the lid 2 is removed, if necessary with the aid of the slit 34 (see FIG. 1) between the lid 2 and the housing 1, and the operating bar 5 is removed from between the guides 22 and 23.
  • This operation is feasible since the abutting element 9 which, as stated above, serves to push the operating bar 5 against the stop surface 24 of the housing, is no longer present.
  • the operating bar 5 is rotated end-toend through l80 with respect to the position it had in the housing 1 (FIG. 2), thus causing the inversion of the springs 7 and 8 and of the bridging arm 6 carrying the movable contact members 6a and 6b.
  • the operatingbar 5 is introduced into the housing 1 in such a way that the protuberance 25 passes between the walls of the guide 23 and the protuberance 26 passes between the walls of the guide 22 of said housing.
  • the lid 2 is then rotated end-to-end through 180 with respect to the position illustrated in FIG. 2 and is connected to the housing. 1 with the securing means 21 and 30, respectively on seats 16 and I7, and the positioning tooth 37 is inserted in the positioning seat 36 of the operating bar 5.
  • the abutting element 9 is located off-center with respect to the center of the lid 2, so that, when the lid 2 is inverted, the element 9 occupies a position different from that which it had when the contact members were normally open. In particular, when the lid 2 is inverted, the element 9 engages the opposite end of the return spring 8, which, in turn, transmits the received thrust to the operating bar 5 to thereby bring the supporting surface 28 into engagement with the stop surface 24 of the housing 1.
  • the over-run spring 7 extends progressively, since one of its ends is in contact with the bridging arm 6 carrying the movable contact members 6a and 6b, which remains stationary, whereas the other end of the spring 7 is around the centering seat 14 on the operating bar 5 which is in motion.
  • the opening of the contact members takes place only when, in consequence of the movement of the operating bar 5, the surface 15 of the window 11 comes into contact with the bridging arm 6 thereby causing separation of the contacts 6a and 6b from the fixed contact members 3 and 4.
  • the return spring 8 again brings the switch to its initial position (FIG. 5), compressing the over-run spring 7 and establishing thereby a good electric contact.
  • the positioning tooth 37 of the lid 2 is always situated inside the positioning seat 36 of the operating bar 5 itself.
  • the electric condition of the switch shown in FIG. 5 is visible on the end of the housing 1 by a normally closed contact symbol not shown but which is under the portion 35 of the lid 2 (FIG. 1).
  • the normally open contact symbol appearing in zone 33 of the housing 1 will be concealed by a lid portion similar to the portion 35, and the symbol for normally closed contacts will be exposed.
  • abutting element 9 permits the separation of the return spring 8 from the over-run spring 7, which ensures that, in the event of a small displacement of the operating bar 5, the movable contact members 6a and 6b remain pressed on the fixed contact members 3 and 4.
  • Another advantage of the invention is that it is easy to change from one condition of the contacts to the other, both because the various elements constituting the movable assembly are all mounted on the bar 5 and are held thereon, and because it is unnecessary to rotate the fixed contact members 3 and 4 thereby permitting the conversion by means of simple steps which do not require a long time.
  • a further advantage lies in the fact that it is not possible to insert the lid 2 in the housing 1 in an incorrect manner.
  • the position of the normally open contacts it can be noted that the position of the lid 2 cannot be different from that illustrated.
  • the positioning tooth 37 would come into contact with the edge 38 of the operating bar 5, preventing in this way the closure of the lid 2 on the housing 1. It is, therefore, ensured that the electric condition visible from the symbol appearing on the end of the housing 1 (in the example, that of zone 33 of FIG. 1) corresponds to the actual electrical condition of the contact members situated inside the housing and which are not visible.
  • An electric switch convertible from normally closed to normally open contacts and vice versa, said switch comprising a housing member having an opening permitting access to the interior thereof, a lid member for covering said opening, means for holding said members together, a pair of fixed contacts mounted in spaced relation on said housing member, a switch operating bar movably and detachably mounted on one of said members for movement between a normal position and an operated position, an abutting element mounted on one of said members, first spring means acting between said bar and said abutting element to urge said bar into its normal position, a bridging arm having contacts thereon and mounted on said bar for movement therewith and for movement with respect thereto from a first position to a second position, and second spring means acting between said bridging arm and said bar to urge said bridging arm into its first position, said abutting element and said bar being changeable from first positions in which the contacts on said bridging arm engage said fixed contacts in said normal position of said bar and are separated from said fixed contacts in said operated position of said bar to second positions in which the contacts on
  • said means for holding said members together comprises an elastic, releasable hooking means secured to one of said members and a hooking means receiving and engaging seat forming part of the other of said members.

Landscapes

  • Engineering & Computer Science (AREA)
  • Manufacturing & Machinery (AREA)
  • Physics & Mathematics (AREA)
  • Electromagnetism (AREA)
  • Push-Button Switches (AREA)
US00313844A 1971-12-22 1972-12-11 Single pole electric switch with contacts convertible from normally open to normally closed and vice versa Expired - Lifetime US3781501A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
IT32766/71A IT940796B (it) 1971-12-22 1971-12-22 Dispositivo elettrico a contatto unipolare trasformabile da contat to mormalmente chiuso a contatto normalmente aperto o viceversa

Publications (1)

Publication Number Publication Date
US3781501A true US3781501A (en) 1973-12-25

Family

ID=11235622

Family Applications (1)

Application Number Title Priority Date Filing Date
US00313844A Expired - Lifetime US3781501A (en) 1971-12-22 1972-12-11 Single pole electric switch with contacts convertible from normally open to normally closed and vice versa

Country Status (3)

Country Link
US (1) US3781501A (fr)
FR (1) FR2164592B1 (fr)
IT (1) IT940796B (fr)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0007551A1 (fr) * 1978-07-31 1980-02-06 Siemens Aktiengesellschaft Dispositif de contacts pontants
EP0011133A1 (fr) * 1978-11-06 1980-05-28 Metzenauer & Jung GmbH Interrupteur à contacts pouvant assurer au choix une fonction d'ouverture ou de fermeture
US6653582B2 (en) * 2001-11-15 2003-11-25 Matsushita Electric Industrial Co., Ltd. Stop lamp switch and method for attaching the same

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2287099A1 (fr) * 1974-10-03 1976-04-30 Telemecanique Electrique Contact a mercure inversible
FR2506508A1 (fr) * 1981-05-20 1982-11-26 Alsthom Cgee Element modulaire de contact et commutateur a commande rotative comportant un tel element
DE19856678C2 (de) * 1998-12-04 2002-01-24 Moeller Gmbh Elektrische Schaltvorrichtung
US6822173B1 (en) 2000-06-07 2004-11-23 Moeller Gmbh Contact element

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2811617A (en) * 1955-09-19 1957-10-29 Gen Electric Electric switch
GB1021255A (en) * 1961-08-11 1966-03-02 Donovan Electric Company Ltd Improvements relating to electrical switches

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0007551A1 (fr) * 1978-07-31 1980-02-06 Siemens Aktiengesellschaft Dispositif de contacts pontants
EP0011133A1 (fr) * 1978-11-06 1980-05-28 Metzenauer & Jung GmbH Interrupteur à contacts pouvant assurer au choix une fonction d'ouverture ou de fermeture
US6653582B2 (en) * 2001-11-15 2003-11-25 Matsushita Electric Industrial Co., Ltd. Stop lamp switch and method for attaching the same

Also Published As

Publication number Publication date
FR2164592B1 (fr) 1975-11-07
IT940796B (it) 1973-02-20
FR2164592A1 (fr) 1973-08-03

Similar Documents

Publication Publication Date Title
US4112277A (en) Push-button switch units
US3781501A (en) Single pole electric switch with contacts convertible from normally open to normally closed and vice versa
US3253092A (en) Double pole switch with reversible contact structure
US2811617A (en) Electric switch
GB1339196A (en) Panel mounted switch
US2897327A (en) Control-station
US3392598A (en) Pushbutton adapter for electrical switch assembly with latched and momentary pushbuttons
US4451720A (en) Device for mounting an electric device, in particular a cam switch on a mounting plate
US2896034A (en) Mounting and operating means for electric switch mechanisms
US2753413A (en) Quick break electric switches
CN210467615U (zh) 一种防误触按钮开关
US4190754A (en) Slide switch actuating apparatus
DE3644956A1 (de) Drucktastenschaltvorrichtung eines melde- und gegebenenfalls behelfsgeraets fuer den frontplatteneinbau
US3045092A (en) Electric switch
US4121076A (en) Convertible switch
AU543979B2 (en) Switching device
US2669616A (en) Electric switch
US3322927A (en) Pushbutton adapter for electrical switch assembly having multiple pushbutton operators
US2096503A (en) Door pusher and light switch
US3172985A (en) Push button assembly
US2153396A (en) Slow break switch
US3294942A (en) Push button switch
GB2042267A (en) An apparatus comprising switch actuating means
BE1011438A3 (fr) Symboles palpables pour recouvrements d'appareils d'installation.
US3121777A (en) Positive feel actuator