Screwless type electrical terminal block

• US 4,759,726 A
• Filed: 08/12/1987
• Issued: 07/26/1988
• Est. Priority Date: 08/13/1985
• Status: Expired due to Term

• Current Assignee: Thomas & Betts International Incorporated (ABB Limited)
• Original Assignee: Reed Devices, Inc.
• Inventors: Gross, Deanna L., Smith, Gregory J., Naylor, Herbert C.
• Primary Examiner(s): McGlynn, Joseph H.
• Application Number:
  US07/085,280
• Time in Patent Office: 349 Days
• Field of Search: 439/725, 439/726, 439/727, 439/728, 439/729, 439/347, 439/436-441, 439/789, 439/806, 439/78
• US Class Current: 439/441
• CPC Class Codes: H01R 12/515 Terminal blocks providing connections to wires or cables
• CPC Class Codes: H01R 4/2412 actuated by insulated cams or wedges
• CPC Class Codes: H01R 4/5008 using rotatable cam

Abstract

A cam-operated screwless electrical terminal block is provided having a generally box-shaped housing with an open top and an aperture in its front side and containing a generally C-shaped electrical terminal having vertically disposed opposing gripping elements the ends of which are adjacent the front aperture of the housing. The top opening carries a cam-lever pivotally mounted such that when the lever arm of the cam-lever is raised the electrical terminal ends are separated, and when the lever arm of the cam-lever is depressed the upper gripping element of the electrical terminal is depressed toward the lower gripping element so that a wire inserted in the front aperture of the housing between the ends of the gripping elements of the electrical terminal is securely held. The electrical terminal within the housing is adapted to make electrical contact with a circuit board and the terminal block is configured in such a way that a wide range of wire sizes may be conveniently and securely held. The cam-lever is provided with a flattened area on the portion of its face which contacts the upper gripping element of the electrical contact when the cam-lever arm is in the depressed position, and the housing and cam-lever arm possess respectively latching detents so that the cam-lever arm is securely maintained in its depressed position after an electrical connection has been made.

Claims

1. A screwless-type terminal block, comprising:

a housing having a base, a passage through the base, an open top constituting a first opening, and a front possessing a second opening, said housing being adapted to receive and hold a cam-lever in said first opening;

an integral and generally C-shaped electrical terminal within said housing, said terminal including top and bottom portions which constitute respectively first and second gripping elements, said first gripping element being moveable toward said second gripping element in response to an applied force, said first gripping element having a first gripping end, said second gripping element having a second gripping end, said first and second gripping ends being generally opposed and projecting toward one another and formed to clamp a wire therebetween when said first gripping element is moved toward said second gripping element, said second gripping element being electrically conducting and having means for connection to a circuit board, said connection means being disposed to cooperate with the passage through the base of said housing to establish electrical connection between said second gripping element and the circuit board; and

a cam-lever having a cam face, said cam-lever being mounted in said first opening such that said cam face contacts the electrical terminal first gripping element, and being operative to move said first gripping element toward said second gripping element, causing said gripping elements to clamp the wire inserted therebetween, to make an electrical connection.

2. The terminal block of claim 1 wherein said connection means is a conductive pin integral with said second gripping element.

3. The terminal block of claim 1 wherein said connection means is an expandable slot, and said passage through the base of said housing is adjacent to said expandable slot, permitting an electrically conducting pin connected to an external header to be inserted into said housing and into clamping contact with said second gripping element.

4. The terminal block of claim 1 wherein said housing possesses a rear as well as two opposing sides having inner surface, each of the opposing sides of said housing possessing on its inner surface a cylindrical boss located on the upper portion thereof toward the front of said housing and opposite the boss on the opposing housing side, each of the opposing sides of said housing also possessing on its inner surface a latching detent located on the upper portion thereof toward the rear of said housing.

5. The terminal block of claim 4 wherein said second gripping element is supported by the base of said housing.

6. The terminal block of claim 4 wherein said cam-lever possesses a body portion, an integral lever arm, and two opposing sides, each of said cam-lever sides possessing a cavity located in said body portion of said cam lever, each of said cavities being located opposite the cavity on the opposing cam-lever side, said cavities permitting mating of said cam-lever with the respective bosses on the two opposing sides of said housing, each of said cam-lever sides also possessing a detent near the end of said lever arm and so located as to mate with the respective latching detents on the two opposing sides of said housing.

7. The terminal block of claim 6 wherein said cam face possesses a flattened spot on the portion of said cam face which is in contact with the first gripping element when said lever arm is in the down position, to discourage accidental lifting of said lever arm.

8. A screwless-type electrical terminal block comprising:

a housing having a base, a passage through the base, a rear, two opposing sides with inner surfaces, an open top constituting a first opening, and a front possessing a second opening, each of the opposing sides of said housing possessing on its inner surface a cylindrical boss located on the upper portion thereof toward the front of said housing and opposite the boss on the opposing housing side, each of the opposing sides of said housing also possessing on its inner surface a latching detent located on the upper portion thereof toward the rear of said housing;

an integral electrical terminal within said housing, said terminal being made of electrically conductive metal, said terminal being generally C-shaped and possessing top and bottom portions, said top and bottom portions constituting respectively upper and lower gripping elements, said lower gripping element being supported by said housing base and having means for connection to a circuit board, said connection means being disposed to cooperate with the passage through the base of said housing, to establish electrical connection between said second gripping element and the circuit board, said upper gripping element being moveable toward said lower gripping element in response to an applied force;

said upper gripping element having an upper gripping end, said lower gripping element having a lower gripping end, said upper and lower gripping ends being generally opposed and projecting toward one another and formed to clamp a wire therebetween when said upper gripping element is moved toward said lower gripping element; and

a cam-lever having a body portion, an integral lever arm, a cam face, and two opposing sides, each of said cam-lever sides possessing a cavity located in said body portion of said cam-lever, each of said cavities being located opposite the cavity on the opposing cam-lever side, said cavities permitting mating of said cam-lever with the respective bosses on the opposing sides of said housing, each of said cam-lever sides also possessing a detent near the end of said lever arm and so located as to mate with the respective latching detents on the housing sides, said cam face contacting said electrical terminal upper gripping element and depressing said upper gripping element toward said lower gripping element when said lever arm is depressed and locked into said detents, causing said gripping elements to clamp the wire inserted therebetween, making an electrical connection.

9. The terminal block of claim 8 wherein said connection means is a conductive pin integral with said lower gripping element.

10. The terminal block of claim 8 wherein said connection means is an expandable slot, and said passage through the base of said housing is adjacent to said expandable slot, permitting an electrically conducting pin connected to an external header to be inserted into said housing and into clamping contact with said lower gripping element.

11. A screwless-type electrical terminal block, comprising:

a housing of electrically insulative material and having a base adapted for mounting on a circuit board, the base having a passage therethrough to permit electrical connection with the circuit board, and the housing further having an interior cavity communicating with an open top and a front opening;

an integral and generally C-shaped electrical terminal supported in the cavity of the housing and having upper and lower gripping elements in normally spaced apart position confronting the front opening, said upper gripping element having a first gripping end, said lower gripping element having a second gripping end, said first and second gripping ends being generally opposed and projecting toward one another and formed to clamp a wire therebetween, said lower gripping element having means for connection to a circuit board, said connection means being disposed to cooperate with the passage through said housing base;

manually operable cam means including a cam-lever and cam body having a camming surface;

means for supporting the cam means on the housing for rotation of the cam body in the cavity of the housing in engagement with the upper gripping element, by rotation of the cam-lever disposed in the open top of the housing;

the cam means being operative with the cam-lever in a raised position to permit the gripping elements to remain apart for insertion of the wire therebetween via the front opening of the housing, and being operative with the cam-lever in a lowered position to cause the gripping elements to close to clamp the wire therebetween.

12. The terminal block of claim 11 wherein said connection means is a conductive pin integral with said lower gripping element.

13. The terminal block of claim 11 wherein said connection means is an expandable slot, and said passage through the base of said housing is adjacent to said expandable slot, permitting an electrically conducting pin connected to an external header to be inserted into said housing and into clamping contact with said lower gripping element.

14. A screwless-type electrical terminal block for connecting a wire to a circuit board, comprising:

a housing of electrically insulative material including;

a base having a connecting passage to the circuit board;

a top having a top opening; and

a front having a front opening to receive the wire;

an integral, generally C-shaped terminal disposed within said housing including;

an upper gripping element;

a lower gripping element supported on said base;

a first end extending from said upper gripping element proximal said front of said housing and projecting generally toward said lower gripping element;

a second end extending from said lower gripping element proximal said front of said housing and projecting generally toward said upper gripping element and generally opposing said first end; and

means for connection to the circuit board, disposed on the lower gripping element cooperate with said connecting passage in said base; and

a cam means for moving said upper gripping element toward said lower gripping element to grip the wire inserted through said front opening between said first end and said second end, said cam means being rotatably mounted in said top opening and including;

a cam lever; and

a cam surface engageable with said upper gripping element upon rotation of said cam means to move said upper gripping element toward said lower gripping element.

15. The terminal block of claim 14 wherein said means for connection to the circuit board comprises a conductive pin integrally formed on said lower gripping element and projecting through said connecting passage in said base to contact the circuit board.

16. The terminal block of claim 14 wherein said first end projecting from said upper gripping element is angled inwardly and away from said front opening;

and

said second end projecting from said lower gripping element is angled inwardly and away from said front opening.

17. The terminal block of claim 14 wherein said base includes standoffs for supporting said housing on the circuit board.

18. The terminal block of claim 14 wherein said cam means includes latching means to retain said cam means in engagement with said upper gripping element when said upper gripping element is moved toward said lower gripping element;

whereby the wire inserted in said front opening is gripped and retained between said first end and said second end.

19. The terminal block of claim 18 wherein said latching means includes a latching detent;

and

said housing includes a cooperative detent projecting inwardly into said top opening for engaging said latching detent;

whereby said latching detent is held by said cooperative detent when said cam means is rotated to cause said upper gripping element to move toward said lower gripping element.

20. The terminal block of claim 14 wherein said means for connection to the circuit board comprises a slot formed in said lower gripping element, to receive a conductive pin projecting from the circuit board and extending through said connecting passage in said base.

21. The terminal block of claim 20 wherein said slot extends into said upper gripping element.

22. A screwless-type electrical terminal block for connecting a wire to a circuit board, comprising:

a housing of electrically insulative material including;

a base having a connecting passage to the circuit board;

a top having a top opening; and

a front having a front opening to receive the wire;

an integral, generally C-shaped terminal disposed within said housing including;

an upper gripping element;

a lower gripping element supported on said base;

a first end extending from said upper gripping element proximal said front of said housing and projecting generally toward said lower gripping element;

a second end extending from said lower gripping element proximal said front of said housing and projecting generally toward said upper gripping element and generally opposing said first end; and

means for connection to the circuit board comprising a tongue cut from said lower gripping element said tongue having a substantially rectangular shape and being bent to project from said lower gripping element through said connecting passage to contact the circuit board; and

a cam means for moving said upper gripping element toward said lower gripping element to grip the wire inserted through said front opening between said first end and said second end, said cam means being rotatably mounted in said top opening and including;

a cam lever; and

a cam surface engageable with said upper gripping element upon rotation of said cam means to move said upper gripping element toward said lower gripping element.

23. A screwless-type electrical terminal block for connecting a wire to a circuit board, comprising:

a housing of electrically insulative material including;

a base having a connecting passage to the circuit board;

a top having a top opening; and

a front having a front opening to receive the wire;

an integral, generally C-shaped terminal disposed within said housing including;

an upper gripping element;

a lower gripping element supported on said base;

a first end extending from said upper gripping element proximal said front of said housing and projecting generally toward said lower gripping element;

a second end extending from said lower gripping element proximal said front of said housing and projecting generally toward said upper gripping element;

means integral with said lower gripping element cooperative via said connecting passage in said base for connection with connecting means of the circuit board; and

a cam means for moving said upper gripping element toward said lower gripping element to grip the wire inserted through said front opening between said first end and said second end, said cam means being rotatably mounted in said top opening and including;

a cam lever; and

a cam surface engageable with said upper gripping element to move said upper gripping element toward said lower gripping element upon rotation of said cam means.

24. The terminal block of claim 23 wherein said uppon gripping element first end projects generally toward said lower gripping element and said lower gripping element second end projects generally toward said upper gripping element first end.