Board mount type contact-connectors

Abstract: A board-in type contact-connector has an insulating housing with a plurality of contacts (20) separately housed in recesses in the insulating housing. Each contact (20) comprises a prong (23) to connect the contact (20) to a printed circuit board, two pairs of connecting jaws (27, 29) having wire-receiving slots (28, 30) with the jaws of each pair being oppositely directed and the two pairs spaced apart; and a pair of oppositely directed crimpable tabs (25) to crimp a wire received in the wire-receiving slots (28, 30), the crimpable tabs (25) being located between the wire connecting jaws (27, 29).

Description: The invention relates to a board mount type contact-connector for use in connecting a plurality of wires electrically and mechanically to a printed circuit board. Various kinds of board mount contact-connectors have been previously proposed among which is the example disclosed in Japanese Utility Model Publication (examined) 61-3090 and shown in Figure 6 of the accompanying drawings. Referring to Figure 6, a contact-connector has a plurality of contacts 1, each of which includes a pin-like connecting prong 2 insertable in a bore 16 in a printed circuit board 15, and a wire-connecting section 3 having two spaced apart pairs of facing connecting jaws 4 each defining a wire-receiving slot 5. The plurality of contacts 1 are individually mounted in respective recesses 7 of an insulating housing 6 with the connecting prongs 2 projecting from the insulating housing 6. Each recess 7 includes a respective opening 8 extending from the top surface to the rear wall which has a strain relief clamp 9 for maintaining a wire 11. A respective opening 10 is provided through which the connecting prong 2 projects. The wire 11 is inserted into the recess 7 through the opening 8 and forced into the wire-receiving slots 5. As it is forced into the slots 5, insulating covering 12 of the wire 11 is cut by the sides of the slots 5, thereby effecting electrical connection between a conductor core 13 of the wire and the connecting jaws 4. Such a contact-connector has the disadvantage that the part of the insulating covering 12 which is closest to a soldered, brazed or welded joint 17 is likely to be melted by heat generated by making the joint and the conductor 13 can become separated from the connecting jaws 4, thereby causing electrical disconnection. Particularly when the connector has a relatively weak holding strength because of a small pitch, such as 1.5mm, the electrical disconnection is most likely to occur. According to the invention there is provided a board mount type contact-connector comprising: an insulating housing; a plurality of contacts separately housed in the insulating housing with each contact comprising means to connect the contact to a printed circuit board, two pairs of connecting jaws having wire-receiving slots, the jaws of each pair being oppositely directed and the two pairs of jaws being spaced apart, characterised in that each contact comprises a pair of crimpable tabs to crimp a wire received in the wire-receiving slots, the crimpable tabs being located between the pairs of wire connecting jaws, each tab including a first portion adapted to be folded over to crimp the wire extending generally perpendicular to the respective tabs, and a further portion extending generally perpendicular to said first portion to engage the wire extending parallel to the respective further portions. Such a board mount type contact-connector can withstand considerable mechanical load and heat and can maintain mechanical and electrical connection between the wire and the connector over a long period of use. The wire connecting jaws and the crimpable tabs are preferably formed by upwardly bending portions of a bottom plate of the respective contact. The invention is diagrammatically illustrated by way of example in the accompanying drawings, in which:- Figure 1 is a plan view showing a contact of a board-in type contact-connector according to the invention; Figure 2 is a perspective view showing the contact of Figure 1; Figure 3 is a perspective view showing a complete board-in type contact-connector having a plurality of the contacts shown in Figures 1 and 2; Figure 4 is a vertical cross-section showing an assembly of a printed circuit board and the board-in type contact-connector of Figure 3; Figure 5 is a cross-sectional view taken on line 5-5 in Figure 4; and Figure 6 is a longitudinal cross-section through a board-in type contact-connector of previously proposed kind fixed to a printed circuit board. Referring to the drawings and firstly to Figures 1 and 2, a board mount type contact-connector has a contact 20 which is of stamped and formed conductive thin material such as phosphor bronze. The contact 20 includes a bottom plate 21, a prong 23 projecting forwardly from the bottom plate 21 via a raised portion 22, side walls 24 and oppositely directed crimpable tabs 25 at each side of the bottom plate 21. The side walls 24 are bent inwardly at their rearward ends 26 to form a first pair of oppositely directed wire connecting jaws 27 defining a wire-receiving slot 28. Each side wall 24 has a horn 24 a at its forward end, which is engageable with an insulating housing 36 in a manner described below: The bottom plate 21 has a second pair of oppositely directed wire connecting jaws 29 defining a wire-receiving slot 30 at the rearward end. The two wire-receiving slots 28 and 30 are in alignment so as to enable a straight wire to be received therein. As shown in Figures 1 and 2, the crimpable tabs 25 are located between the first wire connecting jaws 27 and the second wire connecting jaws 29. Each tab 25 has a top end 25 a bent inwardly and an ear portion 25 b projecting rearwardly which is designed to maintain the wire crimped by the tabs 25. The first and second wire connecting jaws 27, 29 and the crimpable tabs 25 constitute a wire-connecting section 31. Each of the contacts 20 is, as shown in Figures 3 and 4, accommodated in a respective recess 37 of the insulating housing 36, with its prong 23 extending downwardly. In this way the contacts 20 are housed separately from each other in the insulating housing 36. The insulating housing 36 is made of electrically insulating plastics such as nylon. Each recess 37 has a first opening 38 extending from the top surface of the housing 36 to a rearward wall in which crimpable strain relief clamps 39 are provided, and a second opening 40 in a forward wall through which the prong 23 of each contact 20 projects downwardly. A wire 11 to be connected is inserted through the first opening 38 into the recess 37 and is forced into the wire-receiving slots 28 and 30 of the wire connecting jaws 27 and 29. When it is forced into the slots 28 and 30, the insulating covering 12 is cut to effect electrical connection between the conductor 13 in the wire 11 and the contact 20. As the wire 11 is forced into the slots 28 and 30, the crimpable tabs 25 are crimped over the wire 11 with the top ends 25 a being pressed onto the insulating covering 12 and the ear portions 25 b being kept in abutment with the sides of the wire 11. In this way the wire 11 is secured in the contact 20. The tabs 25 can be bent over without requiring an extra process at the same time as the wire 11 is forced into the wire-receiving slots 28 and 30 for example by a member (not shown) engaged in a transverse groove which is provided in a top face 41 of the insulation housing 36 and has side walls 42. Such board mount type contact-connectors can ensure that the wire 11 is firmly maintained in the contact 20 against any mechanical load because of the disposition of the crimpable tabs 25 between the connecting jaws. The contact-connector of the invention can be particularly advantageous at a small pitch, such as 1.5mm, to hold thin wires.

Claims: A board mount type contact-connector comprising: an insulating housing (36); a plurality of contacts (20) separately housed in the insulating housing (36) with each contact (20) comprising means (23) to connect the contact to a printed circuit board (15), two pairs of connecting jaws (27, 29) having wire-receiving slots (28, 30), the jaws of each pair being oppositely directed and the two pairs of jaws (27, 29) being spaced apart, characterised in that each contact (20) comprises a pair of crimpable tabs (25) to crimp a wire (11) received in the wire-receiving slots (28, 30), the crimpable tabs (25) being located between the pairs of wire connecting jaws (27, 29), each tab including a first portion (25a) adapted to be folded over to crimp the wire (11) extending generally perpendicular to the respective tabs (25), and a further portion (25b) extending generally perpendicular to said first portion (25a) to engage the wire (11) extending parallel to the respective further portions. A board mount type contact-connector according to Claim 1, wherein the crimpable tabs (25) are formed from upwardly bent portions of a bottom plate (21) of the respective contact (20).

Inventors: NAKASHIMA TERUMI, TANAKA TAKESHI, NAKASHIMA, TERUMI, TANAKA, TAKESHI
Applicants: NIPPON ACCHAKUTANSHI SEIZO KK, NIPPON ACCHAKUTANSHI SEIZO KABUSHIKI KAISHA
Application year: 1989
Main classification: H01R4
IPC codes: H01R12, H01R4