GB2213419A

GB2213419A - Tool for inserting wire wrap contact pins into circuit boards

Info

Publication number: GB2213419A
Application number: GB8820137A
Authority: GB
Inventors: Howard Lawrence; Andrew John Horsfield
Original assignee: BICC PLC
Current assignee: Balfour Beatty PLC
Priority date: 1987-12-10
Filing date: 1988-08-24
Publication date: 1989-08-16
Anticipated expiration: 2008-08-24
Also published as: GB8820137D0; GB2213419B; GB8728858D0

Abstract

A simple and inexpensive tool for facilitating insertion into a hole of a perforated circuit board of a wire wrap contact pin having, at its trailing end and extending laterally relative to its axis, an integral arm which, when the pin is engaged in said hole, bears against a major surface of the circuit board, comprises a rigid elongate member 1 having at one end a pair of spaced apart laterally extending shoulders 3 which define a channel 4 therebetween. Each shoulder 3 has a thickness which is less than the distance between the lateral arms when the pins are so positioned in holes in a circuit board that their lateral arms overlie holes in adjacent rows or columns of the board. The channel 4 has a width slightly greater than the thickness of the lateral arm and a depth less than the height of the arm. The shoulders 3 may be formed at the free end of a head that is detachably secured to member 1 and spring loaded relative thereto. The member 1 includes an integral or detachable handle 5. <IMAGE>

Description

TOOL FOR INSERTING WIRE WRAP CONTACT PINS INTO CIRCUIT BOARDS A known kind of circuit board comprises a substantially rigid board of which at least the major surfaces are of electrically insulating material, which carries on one or each of its major surfaces a pattern of strips and/or pads of metal or metal alloy of high electrical conductivity, usually but not necessarily copper, and which has, extending through the board and underlying the electrically conductive metal strips and/or pads, a multiplicity of mutually spaced holes.

Circuit boards of this kind will hereinafter, for convenience, be referred to as circuit boards of the kind described".

It is the current practice to effect electrical connection between the leads of a surface mounted component and appropriate electrically conductive strips and/or pads of a circuit board of the kind described by means of an adaptor having pins which are appropriately spaced for electrical connection in holes in the circuit board and having an array of contacts, generally referred to as "footprints", of metal or metal alloy of high electrical conductivity which are electrically connected to said pins by electrically conductive tracks on the surface of the adaptor and which are so mutually spaced apart that the leads of a surface mounted component can be soldered or otherwise electrically connected thereto.

In the specification of our co-pending British Patent Application No: 88/ filed on the same day as the present application there is described, for use with a circuit board of the kind described, a kit of parts for the assembly of an adaptor for effecting electrical connection between the leads of a surface mounted component and electrically conductive strips and/or pads of the circuit board, which kit of parts can be used to assemble any one of a plurality of adaptors with arrays of footprint, differing from one another.The kit of parts comprises a multiplicity of wire wrap contact pins each suitable for insertion in, and for effecting electrical contact with, an electrically conductive strip or pad of a circuit board of the kind described and each having, integral with the trailing end of the pin and extending laterally with respect to its axis, an arm which, when the pin is engaged in a hole in the circuit board, bears against a major surface of the board and is adapted to constitute a footprint of an adaptor, said multiplicity of wire wrap pins comprising at least two groups of wire wrap pins, the lateral arms of the pins of each group being identical with one another and the lateral arms of the pins of one group differing from the lateral arms of the pins of the or each other group, the lateral arms of the pins of said groups being of such shapes that an adaptor for any one of a plurality of surface mounted components having arrays of leads differing from one another can be assembled on a circuit board of the kind described by selecting from said groups wire wrap pins having appropriate lateral arms, and by inserting the selected wire wrap pins in holes in the circuit board and positioning the lateral arms of the selected wire wrap pins on a major surface of the board in accordance with a predetermined pattern.

With a view to facilitating positioning of the lateral arm of a wire wrap pin in accordance with a predetermined pattern when the pin is inserted in a hole in a circuit board of the, kind described, preferably the trailing end of each wire wrap pin of at least one of said groups of wire wrap pins is integral with the lateral arm at a position at or near one end of the arm and the lateral arm has, at or near the other end of the arm, an integral supplementary pin which is so spaced from the wire wrap pin that the supplementary pin will engage in another hole in the circuit board (so that in side elevation the pin is approximately of inverted U-shape). The supplementary pin of said wire wrap pin may be of a shorter length than that of the wire wrap pin.In some circumstances, the supplementary pin of said wire wrap pin may be of such a transverse cross-section that it is suitable for use as a supplementary wire wrap pin.

It is an object of the present invention to provide a simple and inexpensive tool for facilitating insertion into a hole of a circuit board of the kind described a wire wrap contact having, integral with the trailing end of the pin and extending laterally with respect to its axis, an arm which, when the pin is engaged in said hole, bears against a major surface of the circuit board.

According to the invention, the pin insertion tool comprises a substantially rigid elongate member having at one end a pair of laterally extending shoulders which extend substantially parallel to one another and which are transversly spaced apart to define a laterally extending channel, each shoulder having a thickness which is less than the distance between the lateral arms of two wire wrap pins when the pins are so positioned in holes in a circuit board of the kind described that the lateral arms of the pins overlie holes in adjacent rows or columns of the board and the channel having a width slightly greater than the thickness of the lateral arm of the wire wrap pin and a depth less than the height of the lateral arm of the wire wrap pin.

The laterally extending shoulders may be formed at the free end of a head which is integral with or detachably secured to one end of the rigid elongate member. Where the head is detachably secured to the rigid elongate member, the head may be so spring-loaded with respect to the elongate member that it is urged axially in a direction away from the member by an associated spring.

The rigid elongate member may have at its end remote from the laterally extending shoulders a handle which is integral with or detachably secured to the member.

When using the pin insertion tool to insert a wire wrap pin into a hole or holes of a circuit board of the kind described, the wire wrap pin, and when present its supplementary pin, is or are partially inserted into a hole or holes of the board. The pin insertion tool is then applied to the pin so that the lateral arm of the pin engages in the channel of the tool and the shoulders depend on opposite sides of the lateral arm and pressure is inserted on the tool to push the pin or pins fully home in the hole or holes until the lateral arm bears against the front face of the board.

The invention is further illustrated by a description, by way of example, of the preferred pin insertion tool with reference to the accompanying drawing, in which: Figure 1 is a side view, drawn on an enlarged scale, of the preferred pin insertion tool, and Figure 2 is an end view, drawn on an enlarged scale, of the preferred pin insertion tool shown in Figure 1.

Referring to the drawing, the pin insertion tool comprises a rigid rod 1 which has upstanding from an end face 2 a pair of laterally extending shoulders 3 which extend parallel to one another and which are transversely spaced apart to define a laterally extending channel 4. Each shoulder 3 has a thickness which is less than the distance between the lateral arms of two wire wrap contact pins when the pins are so positioned in holes of a circuit board of the kind described that the lateral arms of the pins overlie holes in adjacent rows or columns of the board. The channel 4 has a width slightly greater than the thickness of the lateral arm of the wire wrap contact pin and a depth less than the height of the lateral arm of the wire wrap pin. A handle 5 is detachably secured to the end of the rod 1 remote from the shoulders 3.

When using the pin insertion tool to insert a wire wrap pin and its supplementary pin into holes of a circuit board of the kind described, the wire wrap pin and its supplementary pin are partially inserted into holes of the board and the pin insertion tool is then applied to the pin so that the lateral arm of the pin engages in the channel 4 of the tool and the shoulders 3 depend on opposite sides of the lateral arm. Pressure is then inserted on the tool to push the pins fully home in the holes until the lateral arm bears against the front face of the board.

Claims

CLAIMS:

1. A tool for facilitating insertion into a hole of a circuit board of the kind described a wire wrap contact pin having, integral with the trailing end of the pin and extending laterally with respect to its axis, an arm which, when the pin is engaged in said hole, bears against a major surface of the circuit board, which tool comprises a substantially rigid elongate member having at one end a pair of laterally extending shoulders which extend substantially parallel to one another and which are transversely spaced apart to define a laterally extending channel, each shoulder having a thickness which is less than the distance between the lateral arms of two wire wrap pins when the pins are so positioned in holes in a circuit board of the kind described that the lateral arms of the pins overlie holes in adjacent rows or columns of the board and the channel having a width slightly greater than the thickness of the lateral arm of the wire wrap pin and a depth less than the height of the lateral arm of the wire wrap pin.

2. A pin insertion tool as claimed in Claim 1, wherein the laterally extending shoulders are formed at the free end of a head which is integral with one end of the rigid elongate member.

3. A pin insertion tool as claimed in Claim 1, wherein the laterally extending shoulders are formed at the free end of a head which is detachably secured to one end of the rigid elongate member, the head being so spring loaded with respect to the elongate member that it is urged axially in a direction away from the member by an associated spring.

4. A pin insertion tool as claimed in any one of the preceding Claims, wherein the rigid elongate member has at its end remote from the laterally extending shoulders a handle which is integral with or detachably secured to the member.

5. A tool for facilitating insertion into a hole of a circuit board of the kind described a wire wrap contact pin having, integral with the trailing end of the pin and extending laterally with respect to its axis, an arm which, when the pin is engaged in said hole, bears against a major surface of the circuit board, a wire wrap contact pin substantially as hereinbefore described with reference to and as shown in the accompanying drawing.