US3255334A - Contact spring set with self-retaining contact elements - Google Patents

Contact spring set with self-retaining contact elements Download PDF

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US3255334A
US3255334A US303092A US30309263A US3255334A US 3255334 A US3255334 A US 3255334A US 303092 A US303092 A US 303092A US 30309263 A US30309263 A US 30309263A US 3255334 A US3255334 A US 3255334A
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Prior art keywords
contact
contact element
insulating body
spring set
elements
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Expired - Lifetime
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US303092A
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Fischer Josef
Krautwald Herbert
Moller Helmut
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Siemens and Halske AG
Siemens AG
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Siemens AG
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    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01HELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
    • H01H50/00Details of electromagnetic relays
    • H01H50/54Contact arrangements
    • H01H50/56Contact spring sets

Definitions

  • CONTACT SPRING SET WITH SELF-RETAINING CONTACT ELEMENTS Filed Aug. 19, 1963
  • the invention disclosed herein is concerned with a contact spring set, especially for relays, which can be produced by simple mechanical operations, comprising at least one contact unit having a plurality of contact springs, forming a compact structural assembly. It is for rational fabrication important that such a contact spring set requires -for its construction only few individual parts and that the assembly of such parts can be efiected substantially without the use of any particular tools and adjusting devices. p
  • a contact spring set having at least one contact unit including a group of contacts forming a compact structural assembly or component, said contact unit comprising an insulating body which is preferably produced by diecasting or the like, channels being formed in said insulating body and extending longitudinally .therethrough, a contact element for insertion into each channel, the respective contact elements having a transversely arched port-ion and having an arm forming a locking ear and/or stamping provided thereon, whereby the respective contact element is after insertion thereof into the corresponding channel, locked in position therein.
  • Each contact unit merely comprises a single insulating-member into which the contact elements can be manually inserted without the use of any particular tool or auxiliary assembly means.
  • the transverse arching and the locking means and stamping provided on the respective contact element hold such element in its inserted position in the insulating body without requiring any corrective adjustment.
  • the diecast or molded insulating bodies and the contact elements can be made so accurate, in a mechanized promay be in known manner actuated by hand or, in the case of a relay, directly or with the aid of intermediate members, for displacement in a direction perpendicularly to the actuating springs.
  • the slide may for the guidance of its contact-actuating motion, extend with one end thereof through the lowermost contact element of a contact unit and with its other end through a protective bracket disposed on top of the contact arrangement. Rectangularly shaped members are advantageously provided for securing the slide against angular rotation.
  • the outer contact elements with their contact points are disposed stationary while the centrally posi- V tioned contact spring is by spot welding or the like fastened to a contact element disposed between the outer contact 1 elements.
  • FIG; 2 illustrates in side elevational view a contact set comprising three contact units such as shown in FIG. 1, and a common slide member serving for the operative actuation of the contacts of all three units;
  • the invention does not only provide savings with respect to individual parts, but also further savings in labor which was heretofore required for the customary corrective adjustments.
  • the contact elements may be made from a metal strip and separated therefrom after providing thereon the required contact points.
  • FIG. 3a indicates in part sectional representation and on a larger scale, a side view of the contact unit shown in FIG. 1;
  • FIG. 3b indicates, likewise in part sectional representation, a top view of the contact unit shown in FIG. 3a.
  • Contact elements 2, 3 and 4 are respectively inserted in the channels 1a. These contact elements are transversely arched along a portion longitudinally thereof as indicated at 10, which is not visible in the drawing, and are after insention inthe respective channels 1a, securely held in position within the insulating body, by locking means and stampings provided thereon.
  • the locking means provided on the contact element 2 is indicated in FIG. 3b at 2a and the stampings are indicated at 2b. Accordingly, the transverse arching of the contact element which produces a spring action provides, jointly with the stamping, a sufficiently firm and secure seating of the contact element in the insulating body, while the locking means provides protection against inadvertent removal or the respective contact element.
  • the contact elements 2 and 4 are provided with contact points indicated respectively at 20 and 40, while the actuating spring 3d, which is provided with contact points 3c,
  • terminals are fastened to the contact element 3.
  • the opposite ends of the contact elements 2, 3 and 4 form terminals respectively indicated at 2e, 3e and 4e. These terminals may be in the form of plugs or soldering tabs.
  • FIG. 2 shows a contact spring set comprising three contact units such as shown in FIGS. 1, 3a and 3b.
  • a protective bracket 8 At the top of the assembly is provided a protective bracket 8. These parts are held together by means of screws 5 extending through holes 1b (FIGS; 1 and 3b) of the respective insulating bodies 1, and cooperating with a threaded plate 7.
  • Numeral 6 indicates a slide which is common to the three contact units, for actuating the break-make springs 3d thereof, such springs engaging into notches 6a formed in the slide.
  • the slide 6 extends through openings 6b in the springs 2 and 4, illustrated in FIG. 1, with its opposite ends extending through the lowermost contact element 4 and through the bracket 8, respectively.
  • a rectangularly shaped guide is provided in the bracket 8 so as to hold the slide 6 against angular rotation.
  • the direction of motion of the slide 6, for actuating the contact springs of the set, is indicated by the arrow.
  • the motion of the slide may be effected by hand as well as directly or in-- directly by the armature of a relay of which the contact spring set forms a part.
  • FIGS. 3a and 3b show the contact unit on a larger scale than it appears in FIGS. 1 and 2.
  • FIG. 3a shows the insulating body 1 partially in section.
  • the contact elements 2, 3 and 4 form at the right ends thereof the terminals 2e, 3e, 42 while the left ends of the contact elements 2 and 4 are provided with the contact points 2c and 4c, respectively.
  • the substantially rigid end of the contact element 4 serves, as already mentioned in conneetion with FIG. 2, as a guide for the slide 6.
  • the actuating spring 30! which is at its outer end provided with contact points 3c, is at its inner end fastened to the centrally disposed contact element 3.
  • the contact points 2c, 30 and 40 form the break-make contact combination which is operatively afiected by the action of the spring 3d responsive to motion of the slide 6 in the direction of the arrow.
  • FIG. 3b shows in part sectional view the arrangement according to FIG. 3a (also FIG. 1) as seen from the top thereof.
  • the section is taken approximately along a line extending along the upper side of the contact element 2,
  • Numeral 111 indicates the holes in the insulating body 1, similarly referenced in FIG. 1, through which screws such as (FIG. 2) extend for securing a contact unit or a set comprising a plurality of contact units.
  • a contact spring set comprising at least one contact unit including a group of contacts, having at least one movable contact, forming a compact structural assembly, said contact unit comprising an insulating body having longitudinally extending channels formed therein for the reception of elongated contact elements respectively inserted in said channels with the opposite ends thereof extending from the corresponding channel, each contact element having an initially arched portion which extends, in inserted position of the corresponding contact element, within the respective channel so as to hold such contact element in pressure engagement with the walls of the channel, and preformed means on each contact element, operative upon insertion thereof within the respective channel, to interlock with said insulating body for additionally retaining such contact element in place in inserted.
  • a contact spring set according to claim 1, wherein said preformed means comprises a part having stampings formed thereon for holding such element in inserted position, and a resilient member which, upon insertion of the contact element in the insulating body, is snapped into interlocking relation therewith for locking the corresponding element against inadvertent displacement from its inserted position.
  • a contact spring set according to claim 1, wherein said contact unit comprises first and second contact elements having relatively stationary portions which extend from said insulating body, said stationary portions being provided with contact points at the free ends thereof, a third contact element secured within a channel of said insulating body and having a movable contact spring secured thereto which spring extends between said relatively stationary portions of said first and second contact elements, said spring being at its free end provided with contact points for cooperation with the contact points carried by said stationary portions and forming a breakmake contact combination the with.
  • a contact set according to claim 6, comprising means forming an arm extending in parallel with each contact element and forming a part thereof for securing the corresponding contact element in its inserted position in said insulating body.

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  • Physics & Mathematics (AREA)
  • Electromagnetism (AREA)
  • Slide Switches (AREA)
  • Manufacture Of Switches (AREA)
  • Contacts (AREA)
  • Push-Button Switches (AREA)

Description

June 7, 1966 J, FISCHER ETAL 3,255,334
CONTACT SPRING SET WITH SELF-RETAINING CONTACT ELEMENTS Filed Aug. 19, 1963 2 Sheets-Sheet l 4 June 7, 1966 J. FISCHER ETAL 3,255,334
CONTACT SPRING SET WITH SELF-RETAINING CONTACT ELEMENTS Filed Aug. 19, 1963 2 Sheets-Sheet 2 United States Patent 3,255,334 CONTACT SPRING SET WITH SELF-RETAINING CONTACT ELEMENTS Josef Fischer, Herbert Krautwald, and Helmnt Moller, Munich, Germany, assignors to Siemens & Halske Aktiengesellschaft, Berlin and Munich, Germany, a corporation of Germany Filed Aug. 19, 1963, Ser. No. 303,092 Claims priority, application Germany, Aug. 20, 1962, S 80,999 8 Claims. (Cl. 200-166) The invention disclosed herein is concerned with a contact spring set, especially for relays, which can be produced by simple mechanical operations, comprising at least one contact unit having a plurality of contact springs, forming a compact structural assembly. It is for rational fabrication important that such a contact spring set requires -for its construction only few individual parts and that the assembly of such parts can be efiected substantially without the use of any particular tools and adjusting devices. p
The invention satisfies the above noted requirements by the provision of a contact spring set having at least one contact unit including a group of contacts forming a compact structural assembly or component, said contact unit comprising an insulating body which is preferably produced by diecasting or the like, channels being formed in said insulating body and extending longitudinally .therethrough, a contact element for insertion into each channel, the respective contact elements having a transversely arched port-ion and having an arm forming a locking ear and/or stamping provided thereon, whereby the respective contact element is after insertion thereof into the corresponding channel, locked in position therein.
Accordingly, the structure provided by the invention.
eliminates the customarily required stacking of contact springs which must be assembled with supportingand insulating plates. Each contact unit merely comprises a single insulating-member into which the contact elements can be manually inserted without the use of any particular tool or auxiliary assembly means. The transverse arching and the locking means and stamping provided on the respective contact element .hold such element in its inserted position in the insulating body without requiring any corrective adjustment.
The diecast or molded insulating bodies and the contact elements can be made so accurate, in a mechanized promay be in known manner actuated by hand or, in the case of a relay, directly or with the aid of intermediate members, for displacement in a direction perpendicularly to the actuating springs. The slide may for the guidance of its contact-actuating motion, extend with one end thereof through the lowermost contact element of a contact unit and with its other end through a protective bracket disposed on top of the contact arrangement. Rectangularly shaped members are advantageously provided for securing the slide against angular rotation.
In the case of a switch-over or break-make contact combination, the outer contact elements with their contact points, are disposed stationary while the centrally posi- V tioned contact spring is by spot welding or the like fastened to a contact element disposed between the outer contact 1 elements.
I contact combination;
FIG; 2 illustrates in side elevational view a contact set comprising three contact units such as shown in FIG. 1, and a common slide member serving for the operative actuation of the contacts of all three units;
duction process, that accurately determined contact forces will be obtained upon assembly of each contact unit. Accordingly, the invention does not only provide savings with respect to individual parts, but also further savings in labor which was heretofore required for the customary corrective adjustments.
The contact elements may be made from a metal strip and separated therefrom after providing thereon the required contact points.
A plurality of contact units may be assembled to form a contact set comprising more individual contacts than can be furnished by one such unit. The assembly may be effected by screw means in cooperation with a threaded plate. The fact that each contact unit, considered by itself, is free of necessity for adjustment, being, as it were, inherently adjusted by .the assembly of its parts, makes it possible to provide a contact set having a plurality of contact units, which contact set is likewise inherently adjusted, since the outer dimensions of the respective insulating bodies can be made with close tolerances.
An advantageous embodiment of the invention provides, for the operative actuation of the contacts of a contact set, a slide which has notches formed therein for receiving the actuating springs of the respective contact units. 'I he slide FIG. 3a indicates in part sectional representation and on a larger scale, a side view of the contact unit shown in FIG. 1; and
FIG. 3b indicates, likewise in part sectional representation, a top view of the contact unit shown in FIG. 3a.
Identical parts areidentically referenced throughout the various figures of the drawings.
The contact set shown in FIG. 1 comprises, so far as its spring equipment is concerned, the smallest contact unit forming a break-make contact combination. The unit comprises the insulating body 1 provided with longitudinal channels In formed therein. 'This insulating body is produced by diecastingor pressure molding, thus reliably securing highly accurate dimensions and eliminating any corrective machining or the like.
Contact elements 2, 3 and 4 are respectively inserted in the channels 1a. These contact elements are transversely arched along a portion longitudinally thereof as indicated at 10, which is not visible in the drawing, and are after insention inthe respective channels 1a, securely held in position within the insulating body, by locking means and stampings provided thereon. The locking means provided on the contact element 2 is indicated in FIG. 3b at 2a and the stampings are indicated at 2b. Accordingly, the transverse arching of the contact element which produces a spring action provides, jointly with the stamping, a sufficiently firm and secure seating of the contact element in the insulating body, while the locking means provides protection against inadvertent removal or the respective contact element.
The contact elements 2 and 4 are provided with contact points indicated respectively at 20 and 40, while the actuating spring 3d, which is provided with contact points 3c,
is fastened to the contact element 3. The opposite ends of the contact elements 2, 3 and 4 form terminals respectively indicated at 2e, 3e and 4e. These terminals may be in the form of plugs or soldering tabs.
FIG. 2 shows a contact spring set comprising three contact units such as shown in FIGS. 1, 3a and 3b. At the top of the assembly is provided a protective bracket 8. These parts are held together by means of screws 5 extending through holes 1b (FIGS; 1 and 3b) of the respective insulating bodies 1, and cooperating with a threaded plate 7. Numeral 6 indicates a slide which is common to the three contact units, for actuating the break-make springs 3d thereof, such springs engaging into notches 6a formed in the slide.
The slide 6 extends through openings 6b in the springs 2 and 4, illustrated in FIG. 1, with its opposite ends extending through the lowermost contact element 4 and through the bracket 8, respectively. A rectangularly shaped guide is provided in the bracket 8 so as to hold the slide 6 against angular rotation. The direction of motion of the slide 6, for actuating the contact springs of the set, is indicated by the arrow. The motion of the slide may be effected by hand as well as directly or in-- directly by the armature of a relay of which the contact spring set forms a part.
As noted before, FIGS. 3a and 3b show the contact unit on a larger scale than it appears in FIGS. 1 and 2. FIG. 3a shows the insulating body 1 partially in section. The contact elements 2, 3 and 4 form at the right ends thereof the terminals 2e, 3e, 42 while the left ends of the contact elements 2 and 4 are provided with the contact points 2c and 4c, respectively. The substantially rigid end of the contact element 4 serves, as already mentioned in conneetion with FIG. 2, as a guide for the slide 6. The actuating spring 30!, which is at its outer end provided with contact points 3c, is at its inner end fastened to the centrally disposed contact element 3. The contact points 2c, 30 and 40 form the break-make contact combination which is operatively afiected by the action of the spring 3d responsive to motion of the slide 6 in the direction of the arrow.
FIG. 3b shows in part sectional view the arrangement according to FIG. 3a (also FIG. 1) as seen from the top thereof. The section is taken approximately along a line extending along the upper side of the contact element 2,
so as to indicate the locking means 2a and the stampings 2b provided on the arm of the element 2 which extends parallel thereto. Only the upper part 2c of the contact point at the left end of the contact element 2 is visible in this figure. Numeral 111 indicates the holes in the insulating body 1, similarly referenced in FIG. 1, through which screws such as (FIG. 2) extend for securing a contact unit or a set comprising a plurality of contact units.
Changes may be made within the scope and spirit of the appended claims which define what is believed to be new and desired to have protected by Letters Patent.
We claim:
1. A contact spring set comprising at least one contact unit including a group of contacts, having at least one movable contact, forming a compact structural assembly, said contact unit comprising an insulating body having longitudinally extending channels formed therein for the reception of elongated contact elements respectively inserted in said channels with the opposite ends thereof extending from the corresponding channel, each contact element having an initially arched portion which extends, in inserted position of the corresponding contact element, within the respective channel so as to hold such contact element in pressure engagement with the walls of the channel, and preformed means on each contact element, operative upon insertion thereof within the respective channel, to interlock with said insulating body for additionally retaining such contact element in place in inserted.
position.
2. A contact spring set according to claim 1, wherein said preformed means comprises a resilient member which, upon insertion of the contact element in said insulating body, is snapped into interlocking relation therewith, for locking the corresponding contact element against inadvertent displacement from its inserted position.
10 3. A contact spring set according to claim 1, wherein said preformed means comprises a part having stampings formed thereon for fimly holding such element in inserted position.
4. A contact spring set according to claim 1, wherein said preformed means comprises a part having stampings formed thereon for holding such element in inserted position, and a resilient member which, upon insertion of the contact element in the insulating body, is snapped into interlocking relation therewith for locking the corresponding element against inadvertent displacement from its inserted position.
5. A contact spring set according to claim 1, comprising a slidable member connected with said movable contact for operatively actuating the contacts formed by said contact unit.
6. A contact spring set according to claim 1, wherein said contact unit comprises first and second contact elements having relatively stationary portions which extend from said insulating body, said stationary portions being provided with contact points at the free ends thereof, a third contact element secured within a channel of said insulating body and having a movable contact spring secured thereto which spring extends between said relatively stationary portions of said first and second contact elements, said spring being at its free end provided with contact points for cooperation with the contact points carried by said stationary portions and forming a breakmake contact combination the with.
7. A contact set according to claim 6, comprising means forming an arm extending in parallel with each contact element and forming a part thereof for securing the corresponding contact element in its inserted position in said insulating body.
7 8. A contact set according to claim 6, wherein said movable contact spring is secured to said third contact element by welding.
References Cited by the Examiner UNITED STATES PATENTS H FOREIGN PATENTS 424,634 8/1947 Italy.
ROBERT S. MACON, Acting Primary Examiner.
ROBERT K. SCI-IAEFER, KATHLEEN H. CLAFFY,
Examiners.
H. O. JONES, Assistant Examiner.

Claims (1)

1. A CONTACT SPRING SET COMPRISING AT LEAST ONE CONTACT UNIT INCLUDING A GROUP OF CONTAITS, HAVING AT LEAST ONE MOVABLE CONTACT, FORMING A COMPACT STRUCTURAL ASSEMBLY, SAID CONTACT UNIT COMPRISING AN INSULATING BODY HAVING LONGITUDINALLY EXTENDING CHANNELS FORMED THEREIN FOR THE RECEPTION OF ELONGATED CONTACT ELEMENTS RESPECTIVELY INSERTED IN SAID CHANNELS WITH THE OPPOSITE ENDS THEREOF EXTENDING FROM THE CORRESPONDING CHANNEL, EACH CONTACT ELEMENT HAVING AN INITIALLY ARCHED PORTION WHICH EXTENDS, IN INSERTED POSITION OF THE CORRESPONDING CONTACT ELEMENT, WITHIN THE RESPECTIVE CHANNEL SO AS TO HOLD SUCH CONTACT ELEMENT IN PRESSURE ENGAGEMENT WITH THE WALLS OF THE CHANNEL, AND PERFORMED MENS ON EACH CONTACT ELEMENT, OPERATIVE UPON INSERTION THEREOF WITHIN THE RESPECTIVE CHANNEL, TO INTERLOCK WITH SAID INSULATING BODY FOR ADDITIONALLY RETAINING SUCH CONTACT ELEMENT IN PLACE IN INSERTED POSITION.
US303092A 1962-08-20 1963-08-19 Contact spring set with self-retaining contact elements Expired - Lifetime US3255334A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
DES80999A DE1185742B (en) 1962-08-20 1962-08-20 Contact spring set

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US3255334A true US3255334A (en) 1966-06-07

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CH (1) CH414014A (en)
DE (1) DE1185742B (en)
DK (1) DK107566C (en)
GB (1) GB1027144A (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3449701A (en) * 1966-03-11 1969-06-10 Ericsson Telefon Ab L M Spring assembly fastening device
US3727015A (en) * 1971-04-12 1973-04-10 Mallory & Co Inc P R Cam operated program timer assembly with replaceable leaf spring contact structure
US4794216A (en) * 1984-12-19 1988-12-27 Gunter Seeger Contact spring for a bistable relay for the switching of high current

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1283390B (en) * 1965-05-05 1968-11-21 Siemens Ag Electromagnetic relay with multiple contact spring set
US3555228A (en) * 1968-04-13 1971-01-12 Nippon Musical Instruments Mfg Contact spring synchronizing switch assembly
DE102006022912A1 (en) * 2006-05-15 2007-11-22 Gruner Ag Relay with contact force reinforcement

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2543036A (en) * 1946-02-27 1951-02-27 Int Standard Electric Corp Electrical contact spring assembly
US2591684A (en) * 1948-12-23 1952-04-08 Int Standard Electric Corp Electrical contact
US2995617A (en) * 1958-11-03 1961-08-08 Malco Mfg Co Self-locking terminal

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2543036A (en) * 1946-02-27 1951-02-27 Int Standard Electric Corp Electrical contact spring assembly
US2591684A (en) * 1948-12-23 1952-04-08 Int Standard Electric Corp Electrical contact
US2995617A (en) * 1958-11-03 1961-08-08 Malco Mfg Co Self-locking terminal

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3449701A (en) * 1966-03-11 1969-06-10 Ericsson Telefon Ab L M Spring assembly fastening device
US3727015A (en) * 1971-04-12 1973-04-10 Mallory & Co Inc P R Cam operated program timer assembly with replaceable leaf spring contact structure
US4794216A (en) * 1984-12-19 1988-12-27 Gunter Seeger Contact spring for a bistable relay for the switching of high current

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Publication number Publication date
DK107566C (en) 1967-06-12
GB1027144A (en) 1966-04-27
DE1185742B (en) 1965-01-21
CH414014A (en) 1966-05-31

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