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US2479234A - Electric connector of the puller type - Google Patents

Electric connector of the puller type Download PDF

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Publication number
US2479234A
US2479234A US765698A US76569847A US2479234A US 2479234 A US2479234 A US 2479234A US 765698 A US765698 A US 765698A US 76569847 A US76569847 A US 76569847A US 2479234 A US2479234 A US 2479234A
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United States
Prior art keywords
plug
recess
contact
contacts
blades
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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
US765698A
Inventor
Herman J Hammerly
Rynold A Salomone
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.)
Trumbull Electric Manufacturing Co
Original Assignee
Trumbull Electric Manufacturing Co
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 Trumbull Electric Manufacturing Co filed Critical Trumbull Electric Manufacturing Co
Priority to US765698A priority Critical patent/US2479234A/en
Application granted granted Critical
Publication of US2479234A publication Critical patent/US2479234A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01RELECTRICALLY-CONDUCTIVE CONNECTIONS; STRUCTURAL ASSOCIATIONS OF A PLURALITY OF MUTUALLY-INSULATED ELECTRICAL CONNECTING ELEMENTS; COUPLING DEVICES; CURRENT COLLECTORS
    • H01R24/00Two-part coupling devices, or either of their cooperating parts, characterised by their overall structure
    • H01R24/28Coupling parts carrying pins, blades or analogous contacts and secured only to wire or cable
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01RELECTRICALLY-CONDUCTIVE CONNECTIONS; STRUCTURAL ASSOCIATIONS OF A PLURALITY OF MUTUALLY-INSULATED ELECTRICAL CONNECTING ELEMENTS; COUPLING DEVICES; CURRENT COLLECTORS
    • H01R13/00Details of coupling devices of the kinds covered by groups H01R12/70 or H01R24/00 - H01R33/00
    • H01R13/66Structural association with built-in electrical component
    • H01R13/70Structural association with built-in electrical component with built-in switch
    • H01R13/713Structural association with built-in electrical component with built-in switch the switch being a safety switch
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01RELECTRICALLY-CONDUCTIVE CONNECTIONS; STRUCTURAL ASSOCIATIONS OF A PLURALITY OF MUTUALLY-INSULATED ELECTRICAL CONNECTING ELEMENTS; COUPLING DEVICES; CURRENT COLLECTORS
    • H01R2103/00Two poles

Definitions

  • stationary contacts are mounted at the bottom of a recess in an insulating receptacle or base and the contact blades or stabs are carried by an insulating body or plug and adapted to frictionally engage the contacts in the base when the carrier is inserted.
  • the contacts and stabs frequently become burred or burned due to the arcing which takes place at the points of contact which makes operation diificult or irregular or in fact impossible. In fact, welding of the contacts sometimes takes place which completely disables the device.
  • One object is to provide a connector wherein incidental pitting or barring of the contact due to arcing will not interfere with the workabilityof the connector.
  • contact is effected by asnap action as the plug is inserted into the receptacle.
  • Fig. 1 is a front view and partial section showing a device embodying one form of the inventlon.
  • Fig. 2' is an end view and partial section of the same, the plug being fully inserted into the receptacle and full contact effected.
  • Fig. 3 is a fragmentary section showing the plug partially inserted into the receptacle and before contact is effected. It also shows a contact blade in the position it takes when the plug is partially withdrawn.
  • Fig. 4 is a similar view after contact is effected but before the plug is fully inserted.
  • Fig. 5 is a perspective view of one blade or stab embodying our invention.
  • Figs. 6 and '7 are longitudinal sectional views showing a simplified form of plug and'receptacle embodying another form of our invention.
  • the base or receptacle 1 and the insertable plug body 8 are each preferably formed of suitable insulating material. Each side of the base has two stationary contacts 9 rounded over at their inner ends to receive corresponding contact stabs or blades l8 carried by the plug.
  • the base has a wall ll surrounding a recess [2 which is adapted to receive the plug 8.
  • Each contact 9 has a clip I3 for receiving a circuit wire (not shown).
  • the bottom M of the base has an opening i 5 at each corner of the recess I2 to allow for the passage of a'plug blade to engage the contact beneath.
  • Each contact and a fuse clip IS the plug body by a bolt or rivet l1.
  • each opening l5' is a guide surface is secured to form of plug 5 Claims. (Cl. 17%328) l8 formed on the inner wall of the recess to direct the'outer 'endof a contact blade.
  • This guide surface may be bounded bya rib side and is inclined inwardly.
  • each stab or blade l0 has a projection 21: adapted to slide along a guide surface l8 as the plug is inserted" into the recess of the receptacle.
  • This projection 21 is not at the end of the blade but is spaced from it so as to leave the tip free to engage the adjacent contact 9, whenthe plug is fully inserted into the recess of the base or receptacle.
  • The'bumps or projections It may beformed by stampingthem out of the blades themselves. In view of v the co truction of the contacts it is unnecessary to round the tip of the plug blades as was customary.
  • the plug blades are secured to the plug body and project at substantially right angles to its plane.
  • the con-- tact blades are all parallel and arranged in pairs so that they are biased laterally toward each other as the plug is inserted in the recess of the receptacle.
  • the edges of the projections should be smooth so as to permit the blades to slide smoothly along the guideways l8 as the plug is inserted.
  • the upper edges of the projections should be rounded oil or inclined slightly so as to a slide smoothly over the edges of the shoulders 20 and automatically retract the blades as the plug is withdrawn.
  • the friction of the parts of the plug-in member and its blades when inserted into the stationary member to en so much force to start the movement that theblades are disengaged quickly from the contacts in a direction normal to their contact surfaces and the danger of sticking or burring is minimized.
  • the -upper edges of the projections should be rounded or bevelled oil so as to have a cam-like action against the shoulders when the plug-in member is withdrawn.
  • the lower edges of the shoulders may also be somewhat rounded or bevelled oil? to coact with the projections in the withdrawing action.
  • the shape of the lower edge of the projection is immaterial except that it should be designed to avoid cutting into or scratching the guide surfaces.
  • Figs. 6 and 7 show; a simplified form of connector in which the insulating base 1 andv the insulating body 8' are in the form of an attachment socket and plug.
  • the stationary contacts 9 and 9" in the body are connected to conventional screw shell and center terminals l3 and I3" respectively.
  • the body has inclined guide surfaces l8 leading to the shoulders 20 just above the contacts 9 and 9".
  • the plug 8 has two resilient contact blades each of which has a cam-like projection 2
  • An electric connector switch comprising a base having a recess, a carrier insertable into said recess, contacts carried by said base, the inner side walls of the recess having guiding surfaces inclined toward each other and having shoulders at the inner ends of said surfaces spaced away from the respective contacts, and resilient contact blades carried by said carrier adapted to engage the respective contacts when the carrier is fully inserted into said recess, each blade having a projection spaced from its tip for sliding along one of said guiding surfaces as the carrier is inserted into said recess and biasing said blade way from the adjacent contact until the projection passes the adjacent shoulder, said shoulder serving to engage the projection as the carrier is withdrawn from the recess and disengage the tip of the blade from the contact by a movement at right angles to the plane of the blade.
  • An electric connector switch comprising an insulating base having a recess, an insulating carrier insertable into said recess, contacts carried by said base, the inner side walls of the recess having guiding surfaces leading toward said contacts and having shoulders spaced away from the respective contacts, and resilient contact blades carried by said carrier adapted to engage the respective contacts when the carrier is fully inserted into said recess each blade having a projection spaced from its end for sliding along one of said guiding surfaces as the carrier is inserted into said recess and bending said blade away from the adjacent contact until the projection passes the adjacent shoulder, whereupon the blade snaps into engagement with the adjacent contact, said shoulder serving to engage the projection as the carrier is withdrawn from the recess and disengage the end of the blade from its contact by a movement at right angles to the planeof the blade.
  • An electric connector switch comprising an insulating base having a recess, an insulating carrier insertable into said recess, contacts carried by said base, the inner side walls of the recess having guiding surfaces inclined toward each other and having shoulders spaced away from the respective contacts, and parallel contact blades carried by said carrier adapted to engage the respective contacts when the carrier is fully inserted into said recess, each blade having a projection near its end for sliding along one of said guiding surfaces as the carrier isinserted into said recess and biasing sad blade awa from the adjacent contact until the projection passes the adjacent shoulder, whereupon the end of the blade engages with the adjacent contact, said shoulder serving to engage the projection as the carrier is withdrawn from the recess and'disengage the blade from its contact by a movement normal to the plane of the blade.
  • An electric connector comprising an insulating member having a recess, oppositely disposed contacts carried by said member adjacent the bottom of said recess, said member having guiding surfaces converging toward each other and, at least one of which terminates at a shoulder spaced away from one of said contacts, and a plug-in member having resilient contact blades insertable into the recess in said insulating memher to engage said contacts, at least one of saidblades being fixed at one of its ends and free to move at itsother end and havinga projection slidable along one of said guiding surfaces when said plug-in member is inserted into the recess of said insulating member and serving to prevent the movable end of said blade from engaging the contact until said projection passes said shoulder, said latter blade being spring loaded as the plugin member is inserted into said recess and snaps into engagement with its contact as said projection passes said shoulder, said shoulder serving to be engaged by said projection and move the blade which has the projection away from its contact in a direction normal to the active surface of its contact when the plug-in member is
  • An electric connector comprising an insulating member having a recess, oppositely disposed contacts carried thereby, said member having guiding surfaces converging toward each other and adjacent said contacts and terminating at shoulders spaced away from said contacts, and a plug-in member having contact blades each secured to said plug-in member at one end of such blade and free to move at its other end, insertableinto the recess in said insulating member to engage said contacts, each of said blades having a projection slidable along one of said guiding surfaces when said plug-in member is inserted into said insulating member and serving to move the blades toward each other and prevent said blades from engaging said contacts until said projections pass said shoulders, said blades being resilient and spring loaded as they are pressed toward each other by their coaction with the converging guiding surfaces of the insulating members as the plug-in member is inserted into said recess and snap into engagement with the respective contacts as the projections pass said shoulders, said shoulders serving to be engaged by said projections and move said blades away from said contacts in

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  • Connector Housings Or Holding Contact Members (AREA)

Description

Aug. 16, 1949. H. .1. HAMMERLY ETAL 2,479,234
ELECTRIC CONNECTOR OF THE FULLER TYPE Filed Aug. 2, 194? 23 25 ,&
- INVENTOR. HERMAN J HAMMERLY 3y NOLD ALSALOMONE Patented Aug. 16, 1949 ELECTRIC CONNECTOR or'rnp. PULLER' TYRE.
Herman I. Hammerly and Rynold'A. Salomone,
Piainville, Conn,
Electric Manufacturing Gompany,
'assignors to The Trumbull Plainville,
Conn,- a corporation of Connecticut Application August 2, 1947, Serial No. 765,698
1 In switches of this type stationary contacts are mounted at the bottom of a recess in an insulating receptacle or base and the contact blades or stabs are carried by an insulating body or plug and adapted to frictionally engage the contacts in the base when the carrier is inserted. In such devices the contacts and stabsfrequently become burred or burned due to the arcing which takes place at the points of contact which makes operation diificult or irregular or in fact impossible. In fact, welding of the contacts sometimes takes place which completely disables the device.
One object is to provide a connector wherein incidental pitting or barring of the contact due to arcing will not interfere with the workabilityof the connector.
The accompanying specification and draw-- ings disclose the invention as applied to switches of the type of Letters Patent 2,289,358.
According to our invention contact is effected by asnap action as the plug is inserted into the receptacle.
Fig. 1 is a front view and partial section showing a device embodying one form of the inventlon.
' Fig. 2' is an end view and partial section of the same, the plug being fully inserted into the receptacle and full contact effected. g
Fig. 3 is a fragmentary section showing the plug partially inserted into the receptacle and before contact is effected. It also shows a contact blade in the position it takes when the plug is partially withdrawn.
Fig. 4 is a similar view after contact is effected but before the plug is fully inserted.
Fig. 5 is a perspective view of one blade or stab embodying our invention. I
Figs. 6 and '7 are longitudinal sectional views showing a simplified form of plug and'receptacle embodying another form of our invention.
The base or receptacle 1 and the insertable plug body 8 are each preferably formed of suitable insulating material. Each side of the base has two stationary contacts 9 rounded over at their inner ends to receive corresponding contact stabs or blades l8 carried by the plug. The base has a wall ll surrounding a recess [2 which is adapted to receive the plug 8.
Each contact 9 has a clip I3 for receiving a circuit wire (not shown). .The bottom M of the base has an opening i 5 at each corner of the recess I2 to allow for the passage of a'plug blade to engage the contact beneath.
Each contact and a fuse clip IS the plug body by a bolt or rivet l1.
In line with each opening l5'is a guide surface is secured to form of plug 5 Claims. (Cl. 17%328) l8 formed on the inner wall of the recess to direct the'outer 'endof a contact blade. This guide surface may be bounded bya rib side and is inclined inwardly.
The lower end of the wall H terminates in a shoulder 20 spaced apart above each contact 9 and each stab or blade l0 has a projection 21: adapted to slide along a guide surface l8 as the plug is inserted" into the recess of the receptacle. This projection 21 is not at the end of the blade but is spaced from it so as to leave the tip free to engage the adjacent contact 9, whenthe plug is fully inserted into the recess of the base or receptacle.
The'bumps or projections It may beformed by stampingthem out of the blades themselves. In view of v the co truction of the contacts it is unnecessary to round the tip of the plug blades as was customary.
The plug blades are secured to the plug body and project at substantially right angles to its plane.
I9 on each As the plug is inserted'in to the receptacle. the blades are biased inwardly as they slide down .the inclined surfaces 18, (8 until the projections 2 i slip below the shoulders 20 and the tips of the blades snap into engagement with the contacts. 9 as shown in Fig. 4. On further insertionof the plug; the'blades slide across the ends of the contacts thus providing a Wiping action. There is thus no tendency for the blade to ride ou as has been previously noted with the plug blades of previous devices. As the plug is Withdrawn the blade I0 slides along contact 9. The bump or projection 2 I then strikes the shoulder 20 which bends the blade [0 away from the contact 9 at i right angles to the plane of the blade.
In the preferred form of the invention the con-- tact blades are all parallel and arranged in pairs so that they are biased laterally toward each other as the plug is inserted in the recess of the receptacle. The edges of the projections should be smooth so as to permit the blades to slide smoothly along the guideways l8 as the plug is inserted. The upper edges of the projections should be rounded oil or inclined slightly so as to a slide smoothly over the edges of the shoulders 20 and automatically retract the blades as the plug is withdrawn.
In switches of this type as set forth in the Hanny Patent 2,289,358 it is customary to have corners 22 and 23 in the receptacle and corners 24 and-'25 on the plug to enable the plug to be inserted in the proper position but prevent insertion in an improper position.
In such a switch the friction of the parts of the plug-in member and its blades when inserted into the stationary member to en so much force to start the movement that theblades are disengaged quickly from the contacts in a direction normal to their contact surfaces and the danger of sticking or burring is minimized. For most favorable action the -upper edges of the projections should be rounded or bevelled oil so as to have a cam-like action against the shoulders when the plug-in member is withdrawn. The lower edges of the shoulders may also be somewhat rounded or bevelled oil? to coact with the projections in the withdrawing action. The shape of the lower edge of the projection is immaterial except that it should be designed to avoid cutting into or scratching the guide surfaces.
Figs. 6 and 7 show; a simplified form of connector in which the insulating base 1 andv the insulating body 8' are in the form of an attachment socket and plug. The stationary contacts 9 and 9" in the body are connected to conventional screw shell and center terminals l3 and I3" respectively. The body has inclined guide surfaces l8 leading to the shoulders 20 just above the contacts 9 and 9".
The plug 8 has two resilient contact blades each of which has a cam-like projection 2| adapted to engage an inclined wall [8 as the blades are inserted into the body. This bends the ends of the blades toward each other until the projections 2| pass the shoulders 20 whereupon and engage,
the ends of the blades move outwardly the stationary contacts 9' and 9".
When the plug is withdrawn the blades slide along the contacts until the projections 2| reach the shoulders 20. Continued withdrawal of the plug forces the blades outwardly and thus breaks the contact connection in a direction normal to the plane of the contacts.
We claim:
1. An electric connector switch comprising a base having a recess, a carrier insertable into said recess, contacts carried by said base, the inner side walls of the recess having guiding surfaces inclined toward each other and having shoulders at the inner ends of said surfaces spaced away from the respective contacts, and resilient contact blades carried by said carrier adapted to engage the respective contacts when the carrier is fully inserted into said recess, each blade having a projection spaced from its tip for sliding along one of said guiding surfaces as the carrier is inserted into said recess and biasing said blade way from the adjacent contact until the projection passes the adjacent shoulder, said shoulder serving to engage the projection as the carrier is withdrawn from the recess and disengage the tip of the blade from the contact by a movement at right angles to the plane of the blade. I
2. An electric connector switch comprising an insulating base having a recess, an insulating carrier insertable into said recess, contacts carried by said base, the inner side walls of the recess having guiding surfaces leading toward said contacts and having shoulders spaced away from the respective contacts, and resilient contact blades carried by said carrier adapted to engage the respective contacts when the carrier is fully inserted into said recess each blade having a projection spaced from its end for sliding along one of said guiding surfaces as the carrier is inserted into said recess and bending said blade away from the adjacent contact until the projection passes the adjacent shoulder, whereupon the blade snaps into engagement with the adjacent contact, said shoulder serving to engage the projection as the carrier is withdrawn from the recess and disengage the end of the blade from its contact by a movement at right angles to the planeof the blade.
3. An electric connector switch comprising an insulating base having a recess, an insulating carrier insertable into said recess, contacts carried by said base, the inner side walls of the recess having guiding surfaces inclined toward each other and having shoulders spaced away from the respective contacts, and parallel contact blades carried by said carrier adapted to engage the respective contacts when the carrier is fully inserted into said recess, each blade having a projection near its end for sliding along one of said guiding surfaces as the carrier isinserted into said recess and biasing sad blade awa from the adjacent contact until the projection passes the adjacent shoulder, whereupon the end of the blade engages with the adjacent contact, said shoulder serving to engage the projection as the carrier is withdrawn from the recess and'disengage the blade from its contact by a movement normal to the plane of the blade.
4. An electric connector comprising an insulating member having a recess, oppositely disposed contacts carried by said member adjacent the bottom of said recess, said member having guiding surfaces converging toward each other and, at least one of which terminates at a shoulder spaced away from one of said contacts, and a plug-in member having resilient contact blades insertable into the recess in said insulating memher to engage said contacts, at least one of saidblades being fixed at one of its ends and free to move at itsother end and havinga projection slidable along one of said guiding surfaces when said plug-in member is inserted into the recess of said insulating member and serving to prevent the movable end of said blade from engaging the contact until said projection passes said shoulder, said latter blade being spring loaded as the plugin member is inserted into said recess and snaps into engagement with its contact as said projection passes said shoulder, said shoulder serving to be engaged by said projection and move the blade which has the projection away from its contact in a direction normal to the active surface of its contact when the plug-in member is with-' drawn from said insulating member.
5. An electric connector comprising an insulating member having a recess, oppositely disposed contacts carried thereby, said member having guiding surfaces converging toward each other and adjacent said contacts and terminating at shoulders spaced away from said contacts, and a plug-in member having contact blades each secured to said plug-in member at one end of such blade and free to move at its other end, insertableinto the recess in said insulating member to engage said contacts, each of said blades having a projection slidable along one of said guiding surfaces when said plug-in member is inserted into said insulating member and serving to move the blades toward each other and prevent said blades from engaging said contacts until said projections pass said shoulders, said blades being resilient and spring loaded as they are pressed toward each other by their coaction with the converging guiding surfaces of the insulating members as the plug-in member is inserted into said recess and snap into engagement with the respective contacts as the projections pass said shoulders, said shoulders serving to be engaged by said projections and move said blades away from said contacts in a direction normal to the active surfaces of said contacts when the plug-in member is withdrawn from said insulating member.
HERMAN J. HAMMERLY.
RYNOLD A. SALOMONE REFERENCES CITED The following references are of record in the file of this patent:
UNITED STATES PATENTS Number Name Date 1,956,949 Good May 1, 1934 1,970,587 Werner Aug. 21, 1934 58 Hanny July 14, 1942
US765698A 1947-08-02 1947-08-02 Electric connector of the puller type Expired - Lifetime US2479234A (en)

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Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3126240A (en) * 1964-03-24 Plug-in bus duct
US3272947A (en) * 1964-05-11 1966-09-13 Murray Mfg Corp Switch contact arrangement
US6254924B1 (en) 1996-01-04 2001-07-03 General Cable Technologies Corporation Paired electrical cable having improved transmission properties and method for making same
US7179110B1 (en) * 2006-06-07 2007-02-20 Chia-Hung Huang Stably fastened safety plug

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1956949A (en) * 1931-07-04 1934-05-01 Charles A Good Electric circuit extension connecter
US1970587A (en) * 1932-02-13 1934-08-21 Garfield Mfg Company Electrical connecter
US2289358A (en) * 1940-06-22 1942-07-14 Trumbull Electric Mfg Co Electric switch

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1956949A (en) * 1931-07-04 1934-05-01 Charles A Good Electric circuit extension connecter
US1970587A (en) * 1932-02-13 1934-08-21 Garfield Mfg Company Electrical connecter
US2289358A (en) * 1940-06-22 1942-07-14 Trumbull Electric Mfg Co Electric switch

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3126240A (en) * 1964-03-24 Plug-in bus duct
US3272947A (en) * 1964-05-11 1966-09-13 Murray Mfg Corp Switch contact arrangement
US6254924B1 (en) 1996-01-04 2001-07-03 General Cable Technologies Corporation Paired electrical cable having improved transmission properties and method for making same
US7179110B1 (en) * 2006-06-07 2007-02-20 Chia-Hung Huang Stably fastened safety plug

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