EP0139786A1

EP0139786A1 - Press fit connector insulator and contact

Info

Publication number: EP0139786A1
Application number: EP83112603A
Authority: EP
Inventors: J. Preston Ammon; Jerry A. Kendall; John D. Martens
Original assignee: Elfab Corp
Current assignee: Elfab Corp
Priority date: 1983-08-05
Filing date: 1983-12-15
Publication date: 1985-05-08
Also published as: DE3376604D1; EP0139786B1; JPS6044983A

Abstract

An insulator body (11) for a press fit connector is configured to have a plurality of identical compartments (14) or sleeves for receiving contacts. Each sleeve has offset shoulders (47a,48a) which mate with projections (44) on the terminals whereby the terminals may be press fitted into a printed circuit board using the insulator body (11) as the press fittool.

Description

FIELD OF THE INVENTION

This invention relates to connectors and more particularly to press fit connectors and terminals therefore for mounting into printed circuit boards.

DESCRIPTION OF THE PRIOR ART

Press fit connectors may utilize several methods of press fitting the contact terminals into a printed circuit board. The terminal may be pressed into the printed circuit board and then the insulator or connector body positioned over the terminals. In another embodiment, the terminals are loaded into the insulator and then a tool presses on the tops of the terminals to press the terminals into the printed circuit board and secure the insulator. In a third method, the terminals are positioned in the insulator by inserting them into the insulator from the bottom side of the insulator and then using the insulator to press the terminals into the printed circuit board.
The first mentioned method is described in U.S. Patent 4,077,694. In this patent the terminals are first either soldered or press fitted into the printed circuit board and then the insulator is positioned over the contacts. The method of press fitting the contacts is not described.
In U.S. Patent 4,127,935 the terminals are placed in the insulator body and a tool is used to press the contacts into the printed circuit board. This method is not suitable for contact terminals that are used in female connectors, connectors that are to be used for card connectors and similar connectors since there is not part of the contact suitable for applying the pressing force.
In U.S. Patent 4,220,393, the insulator is used to press the contact into the printed circuit board by providing long tabs at each side of the terminal and forming the tabs into a circular or "C" configuration. This procedure has a disadvantage in that the long tabs are stamped from the same material as the terminals and formed as a part thereof so that terminals with very close spacing between the terminals cannot be formed. A second method is disclosed wherein a pressing collar is used. However, this adds to the cost of the terminal since it has to be made separately and assembled with the terminal prior to press fitting the terminal.
In order to press fit terminals with the insulator body of the connector, there should be an area as-large as possible for pressing to reduce the strain on the insulator and minimize the pressing force required to seat a large number of connectors. The large pressing area on the terminal should be achieved in a manner to permit the stamping of contact terminals with any desired spacing between the terminals, and the pressing areas should be made with the terminal using one stamping process.

SUMMARY OF THE INVENTION

The invention is to a connector insulator body that is used to press fit contact terminals into a printed circuit board. The insulator is molded with a plurality of shoulders that are used to press against several extensions, protrusions or punched out tabs on the contact terminal. An important feature of the invention is to provide sufficient shoulder area on the insulator and sufficient press points on the terminal to minimize the force required to press the terminal into the printed circuit board without damaging the insulator and/or terminal. DESCRIPTION OF THE DRAWINGS

Figure 1 illustrates a card edge connector utilizing the present invention;
Figures 2a and 2b illustrate a contact used with the card edge connector of Figure 1;
Figure 3 is an end view in section of the connector of Figure 1;
Figure 4 is a partial view in section along the length of the connector of Figure 1,
Figure 5 is the same as Figure 3 with the terminal removed;
Figure 6 is a partial bottom view of the insulator of Figure 1 with the terminals removed;
Figure 7 is a second embodiment of the invention illustrating another style of connector;
Figures 8a and 8b illustrate a contact terminal which may be used with the connector of Figure 7;
Figure 9 is a cross sectional view of the connector of Figure 7;
Figure 10 is a partial sectional side view of the connector of Figure 7;
Figure 11 is a cross sectional view of the connector of Figure 7 with the terminals removed;
Figure 12 is a partial bottom view of the connector of Figure 7;
Figures 13a and 13b illustrate a contact terminal having straight contact pins on both ends; and
Figures 14a and 14b illustrate a contact terminal as in figures 8a and 8b including additional press areas.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Illustrated in Figure 1 is one embodiment of the invention. A card edge connector insulator 10 has a plurality of contact terminals 12 extending from the bottom thereof. These terminals are of the type that are press fitted into a printed circuit board (not illustrated). The insulator is used to press the terminals into the printed circuit board as hereinafter described. The insulator 10 has two parallel side walls 11 that are connected by transverse walls, one part of which is represented by the numeral 19. A slot 18 extends through the central part of the insulator and along its entire length. The slot 18 has two parallel side walls 15 and a plurality of equally spaced openings 17 in the side walls 15 that extend the length of the insulator. Each side wall 11 has a beveled inside edge 16 for guiding a card into the connector, and the tops of the side walls have openings 14 which are the same in number and are aligned with the openings 17. As hereinafter illustrated, each of the openings (14, 17) houses or is identified with a single contact terminal. The end walls 13 of the insulator are such that several connectors may be placed end-to-end to accommodate long printed circuit boards or the ends 13 may be adapted to receive end caps as described and claimed in copending application Serial No.
, filed , and entitled MODULAR CONNECTOR. Figures 2a and 2b illustrate one embodiment of a contact terminal that may be used with the insulator of Figure 1 to provide a press fit connector. Terminal 12 is made of several regions. End 34 is a contact end which is pressed through a printed circuit board and may be soldered to or connected to by a wire wrap tool. A compliant region 33 is the part of the terminal that is press fitted into the printed circuit board. A compliant region is a part of the terminal that will deform upon being press fitted into a printed circuit board and retain the terminal in the circuit board without extreme deformation of the hole and the board surrounding the hole into which the terminal is press fitted. Flat region 30 is designed to have a punched out tab 32. Tab 32 has a flat surface 32a which is used to press the terminal into a printed circuit board. The flat region 30 also has two flat topped shoulders 31 which are also used in press fitting the terminal into a printed circuit board. It is the combined areas 32a and 31 which provide a sufficiently large surface in order to press the terminal into a printed circuit board without damaging the insulator and/or terminal.
Terminal 12 has a curved spring end 35, terminating in end 35a, which is used to contact a card edge connector.
Figure 3 is a cross sectional view of the insulator of Figure 1 showing the terminal 12 in place. The terminal is inserted from the bottom of the insulator so that the curved end 35 extends out opening 17. End 35a is positioned behind inside part of inner wall 15 to hold the terminal in position. The terminal is limited in its upward movement by a vertical rib 36. Shoulder 31 of terminal 12 abutts against a bottom surface 36a of rib 36 to limit the upward movement of the terminal. In similar manner, it is, in part, the pressing downwardly of surface 36a against shoulder 31 that press fits the terminal into a printed circuit board. Side wall 11 has an offset region 37 with a flat top area 37a. The area 37a is also used in press fitting a terminal into a printed circuit board. The flat surface 37a presses downwardly against the flat area 32a of tab 32.
Figures 4, 5 and 6 illustrate the various parts used in applying the downward force to press fit the terminal. In Figure 4 it may be observed that each terminal resides between two transverse walls 19. Each wall 19 has a rib 36 with a pressing end 36a, providing two points of pressure on each side of the terminal, by pressing against the two shoulders 31. The third pressure point is against the tab surface 32a. This is best illustrated in Figure 3.
Figure 5 illustrates the cross sectional view of the insulator without the terminal in place. Figure 6 is a partial bottom view of the insulator which illustrates the three pressing surfaces, the two 36a surfaces, one in each transverse walls, enclosing the terminal compartment, and one in the side wall of the insulator.
A second embodiment of the invention is illustrated in Figure 7. Illustrated is a multicontact connector that may be press fitted into a printed circuit board. The connector 20 has contact terminals 22 extending from the under side. The insulator has a plurality of sleeves or compartments into each of which a single contact is placed. The compartments are separated in the direction transverse to the length of the connector by walls 24 which extend from the top to the bottom of the insulator. The compartments are separated along the length of the insulator by walls 24a which also extend from the top to the bottom of the connector. Each compartment has a beveled lip around its top opening to guide a mating terminal into the compartment and into electrical connection with the terminal 22 therein.
Each insulator may be terminated at each end with a mounting platform 25 and may have a hole 25a therein through which a screw or rivet may be placed to secure the insulator to a printed circuit board.
Figure 7 illustrates a three row connector. However, there may be one or more rows, depending upon the number of desired contacts in the connector.
Figures 8a and 8b illustrate one embodiment of a contact terminal that may be used with the insulator of Figure 7. The terminal is an elongated metal terminal with one end 46 suitable as either a solder terminal or a wire wrap terminal. A compliant section 45 is press fitted into a printed circuit board to make contact with circuit patterns on the board and to hold the connector on the printed circuit board. The terminal has a flat central region 42 which has two punched out tabs 43 and 44. These tabs have flat regions 43a and 44a, respectively, and are used in press fitting the terminal into a printed circuit board.
Figures 13a and 13b illustrate a second embodiment of a contact terminal. The terminal is similar to the terminal of Figures 8a and 8b except that both ends 51 and 52 are straight pin contacts. A compliant region 53 is adjacent to contact 52 and a flat region 54 is between compliant region 53 and contact 51. The flat region has two press shoulders 55 and 56, and a punched out tab 57. The end 58 of tab 57 is also used in press fitting the terminal into a printed circuit board using the connector insulator body.
Figures 14a and 14b illustrate another embodiment of a contact terminal. The terminal has a straight pin contact 63 and a wishbone type contact 61, 62 on the other end. In the central part of the terminal is compliant region 64 and a flat region 65 including press shoulders 66 and 67 and press tab 68, 69.
Each of the terminals in Figures 8a, 8b, 17a, 13b, 14a, and 14c may be used in the insulator of the present invention and variations thereof. Each terminal is a press fit terminal in respect of the fact that the insulator is used to press fit the terminal into a printed circuit board.
Figures 9 and 11 are cross sectional views of the insulator of Figure 7. Figure 11 is the same as Figure 9 with the terminals removed. As illustrated the sleeves 23 are separated by walls 24. Each wall 24 has two offset regions 47, 48 formed therein. One offset region 47 is on one side of a wall and the other offset region 48 is on the other side. In this manner there is an offset region 47 and an offset region 48 associated with each sleeve 23. When a terminal 20 is inserted into a sleeve 23 tab 44 resides in offset region 48 and tab 43 resides in offset region 47. To press fit the terminals into a printed circuit board, a downward force is asserted on the top of the insulator. Shoulder 47a presses downward on tab surface 43a and shoulder 48a presses downward on tab surface 44a thereby press fitting the terminals into the printed circuit board (not illustrated).
Figure 10 is a partial cross sectional view of the side of the insulator illustrated in Figure 7. It should be noted that sleeve 23 is tapered, being larger at the bottom and smaller at the top, and when terminal 20 is inserted into sleeve 23, the edge 50 of terminal 20 comes into frictional contact with the side walls of the sleeves. It is the frictional forces between the two that holds the terminal in the sleeve until the insulator and the contacts are press fitted into the printed circuit board.
Figure 12 is a partial bottom view of the insulator illustrating the location of the shoulders 47a and 48a which are used in the press fitting of the terminals 20.
Although specific embodiments of insulators and terminals have been illustrated, other embodiments and modifications will be suggested to those skilled in the art and such other embodiments and modifications are deem to fall within the scope of the invention as herein described and claimed.

Claims

1. A press fit insulator for a connector adapted to receive and be used as the means for press fitting a plurality of contact terminals into a printed circuit board, said insulator characterized by a block of insulating material (11) formed with a plurality of identical compartments (14, 23) along its length formed by walls, each compartment having a plurality of offset shoulders (37a, 47a) associated therewith formed in one or more walls of each compartment, each shoulder mating with matching projections (31., 32a, 43a, 44a) on a contact terminal such that the insulator is utilized to press fit the contact terminal into a printed circuit board.

2. The insulator according to Claim 1 wherein two ends (13) of the insulator are formed with an end wall such that two or more insulators may be placed end-to-end to form a connector of a desired length.

3. The insulator according to Claim 1 wherein the insulator may be cut adjacent to one of the walls to make a connector of a shorter length.

4. The insulator according to Claim 1 wherein the offset shoulders (47a, 48a) in the walls for each compartment are vertically displaced from each other..

5. The insulator according to Claim 1 wherein the offset shoulders for adjacent compartments in the same wall are vertically displaced from each other.

6. A contact terminal for use with the press fit connector according to claim 1 where the connector insulator is used as the press fit means, characterized by a first contact end, a second contact end, and first and second intermediate regions, said first intermediate region adjacent said first contact end and comprising a compliant region (45) for press fitting into a printed circuit board, said second intermediate region (50) between the second contact end and said first intermediate region comprising a flat region (42) having at least one punched out tab (43, 44) for mating with said connector insulator so as to use the connector insulator to press fit the connector terminal into the printed circuit board.

7. The terminal according to Claim 8 characterized in that the flat region has two parallel faces and two punched out tabs (43, 44), one punched tab extends out one face of the flat region and the other tab extends out the other face of the flat region.

8. The terminal according to claim 9 characterized in that said two punched out tabs are vertically aligned.

9. The terminal according to Claim 9 characterized in that the flat region includes two shoulders (31) which may be used to press fit the terminal into a printed circuit board.

10. The terminal according to claim 8 characterized in that the second contact end (46) is a straight pin contact.

11. The terminal according to claim 8 characterized in that said first contact end is a flow solder contact.

12. The press fit insulator, according to claim 1 characterized in that each compartment having offset shoulders associated therewith, at least one shoulder formed in each of two opposite walls, each of said shoulders spaced to mate with matching projections on a contact terminal, such that the insulator is utilized to press fit the contact terminal into a printed circuit board.