A contact for an electrical connector

Abstract

 This invention relates to an electrical connector that has insertable and removable contacts (20) retained and sealed against moisture by a one piece molded rubber insert (30). The invention is characterized by a contact (20) having two annular grooves (24, 25) formed by acutely angled flat surfaces (26, 27) that are adapted to mate with a complimentary shaped bore (31) in a molded rubber insert (30).

Description

[0001] This invention relates to an electrical connector and more particularly to an electrical contact mounted within the connector.

[0002] Electrical connectors generally include a plug and receptacle, each of which has an insert of dielectric material provided with multiple openings within which electrical contacts are retained. The insert is introduced into the rear end of a metal shell or housing of the connector where it is held in place by some means, such as a nut. Some connectors provide for rearward insertion and front or rear release of electrical contacts, while other connectors provide for front insertion and front or rear release of electrical contacts. These feature are desirable and facilitate the assembly and servicing of the connector. Examples of a prior art electrical connector having insertable and removable contacts may be found in U.S. Patents 3,165;369 entitled "Retention System for Electrical Contacts" issued July 12, 1966; and 3,221,292 entitled "Electrical Connector" issued November 30, 1965. In the foregoing patents, the contacts are retained within the connector housing by a retention mechanism and the contacts are sealed from moisture by a separate rubber grommet which fits tightly around the incoming wires to prevent moisture from entering into the area between the contacts. Generally, where removable contacts and a moisture seal is required three or more parts were sandwiched together to accomplish these functions.

Disclosure of the Invention

[0003] This invention provides an electrical connector that has insertable and removable contacts retained and sealed against moisture by a one piece molded rubber insert. The invention is characterized by a contact having two annular grooves formed by acutely angled flat surfaces that are adapted to mate with a complementary shaped bore in a rubber insert.

[0004] Accordingly, it is an advantage of this invention to provide an insert for an electrical connector that combines the contact retaining functions and moisture sealing functions into a single integral part.

[0005] It is also an advantage of this invention to eliminate the need to sandwich two or more parts together to accomplish the retention and moisture sealing of a contact with an electrical connector.

[0006] It is another advantage of this invention to decrease the cost of assembling an electrical connector.

[0007] It is another advantage of this invention to eliminate the need for adhesives to seal the multiple parts that made up a prior art connector insert.

Detailed Description of the Invention

[0008] FIGURE 1 illustrates an electrical contact.

[0009] FIGURE 2 is a diagrammatic view of an electrical connector incorporating the principles of the invention.

[0010] Referring now to the drawing, FIGURE 1 illustrates a pin-type electrical contact 20 having a central axis A, a forward mating portion 21, an intermediate portion 22 and a rear wire receiving portion 23. The intermediate portion 22 includes two grooves 24 and 25.. Each groove 24, 25 includes acutely angled flat surfaces 26, 27. The forward angled surface 26 is at an angle of about 30 degrees from the central axis of the contact. The surface 27 rearward of the forward surface 26 is at an angle of about 15 degrees from the central axis of the contact 20. A rearwardly facing shoulder 28 is located between the intermediate portion 22 and end portion 23. The angle of the surfaces 26, 27 are designed in this embodiment to require a lower removal force from the insert 30 than insertion force. The angles could be reversed if a reverse result is desired, i.e., higher removal force.

[0011] FIGURE 2 is a diagrammatic view of an electrical connector incorporating the principles of the invention. The electrical connector includes a metal housing 10 and a dielectric insert 30 having mounted therein a male pin-type contact 20 or a female socket-type contact 20. Each insert 30 includes a bore 31 having mounted therein a respective contact 20. Each of the bores 31 in the insert 30 includes two radially inwardly projecting portions or restrictions that mate with the annular grooves 24, 25 in the contact 20. Each bore 31 has an inner diameter that is slightly less than the outside diameter of the contact 20 so as to provide a pressure tight seal around the contact. The angle of the surfaces 26, 27 of each of the grooves 24, 25 determine the retention strength of the contact when it is inserted into the insert 30. By changing the angle of the surfaces 26, 27 the force required to insert and remove the contact 20 from the insert 30 can be changed. To prevent further rearward movement of a contact 20 mounted in the connector insert 30 a plate 40, comprised of a hard dielectric material, is fixedly mounted within the housing 10. The rear shoulder 28 of the contact 20 abuts against a forwardly facing shoulder 23 on the plate 40 to prevent further rearward movement of the contact 20 in the insert 30. The plate 40 acts as a positive stop when a contact 20 is inserted into the bore 31 of the insert 30 from the front of the connector housing 10. The insert 30 is comprised of an elastomer such as rubber and preferably has a durometer of about 65.

[0012] While a preferred embodiment of the invention has been disclosed, it will be apparent to those skilled in the art that changes may be made to the invention as set forth in the appended claims and, in some instances, certain features of the invention may be used to advantage without corresponding use of other features. For instance, there could be one groove instead of two grooves in each contact 20 and the angle of the surfaces 26, 27 could be the same. Accordingly, it is intended that the illustrative and descriptive materials herein be used to limit the principles of the invention and not to limit the scope thereof.

Claims

1. A contact for electrical connector of the type having: a housing (10) having a forward portion (11) and a rearward portion (12); a plurality of elongated contacts (20) each having a forward mating portion (21), an intermediate portion (22) and a rear wire receiving portion (23); and means for mounting said contacts in said housing including an insert (30) having a plurality of bores (31) therein, each bore (31) having a portion of a respective contact (20) therein, the invention characterized by:

each of said contacts (20) having in the intermediate portion (22) at least one annular groove (24, 25) therein having two surfaces (26, 27), each of said surfaces (26, 27) acutely angled from the central axis (A) of said contact (20); and wherein

each bore (31) in said insert (30) has at least one radially inwardly projecting portion (31, 32) that mates with a respective annular groove (24, 25) in said contact.

2. The electrical connector combination as recited in Claim 1 wherein, the angle of said first surface (26), foward of said second surface (27), is about 30 degrees from the central axis (A) of said contact (20) and the angle of said second surface (27) is about 15 degrees from the central axis (A) of said contact (20).

3. The combination as recited in Claim 1 wherein the angle of the first surface is greater than the angle of the second surface whereby the contact requires a lower removal force than insertion force.

4. The combination as recited in Claim 1 wherein the angle of the first surface is smaller than the angle of the second surface whereby the contact requires a higher removal force than insertion force.

5. The contact as recited in Claim 2 wherein the contact includes a rearwardly facing shoulder (28).

6. The combination as recited in Claims 1, 2, 3 or 4 wherein there are two grooves (24, 25) in each of said contacts (20) and two radially inwardly projecting portions in each bore (31) of said insert (30).

7. The combination as recited in Claims 1, 2, 3 or 4 wherein the insert is comprised of a rubber having a durometer of about 65.

Drawing