GB2128922A - Wiring implements - Google Patents

Abstract

A wiring implement for conductively connecting an insulated wire (W) to an insulation displacement (ID) connector (10) comprises a pair of arms (56, 58) spaced from one another at a tip of the implement and capable of cooperating with one another to push the wire into an ID slot (26) of the connector (10) to effect the connection. One arm (56) is fixed with respect to a body of the implement. The other arm (58) is movable into and out of the body of the implement so as to adopt, in a rest condition, a position in which its free end is disposed further from the body than that of the fixed arm (56). The movable arm (58) is provided with wire guide means (64) for guiding the wire (W) to extend towards the fixed arm from a position beyond the free end of the fixed arm (56) when the movable arm is in the rest condition, whereby the movable arm (58) can be moved into a position in which the wire is positioned at the mouth of the ID slot (26) and subsequent movement of the implement towards the connector (ID) will then cause retraction of the movable arm (58) so that the free end of the fixed arm (56) contacts the wire (W) and pushes it into the slot (26). <IMAGE>

Description

SPECIFICATION Wiring implements This invention relates to wiring implements for conductively connecting insulated wires to insulation displacement (ID) connectors. As used herein, the expression "ID connector" means a connector having at least one ID slot into which at least one insulated wire can be pushed, the slot being such as to displace the wire insulation as the wire is pushed therein so as to establish- a conductive connection with the wire.

ID connectors are well known in the art.

They are typically designed so as to be receivable in boards, for instance printedcircuit boards, and enable a highly convenient form of point-to-point wiring to be effected on the boards. Like wire-wrapping, the use of ID connectors has the advantage that solder is not required to satisfactorily fix wires in place.

However, the insulation displacement technique is superior to wire-wrapping in that it is relatively simple to effect, it generally enables more wires to be attached to a single connector and, possibly most importantly, the wires can generally be removed from and re-secured to the connector with a minimum of trouble and damage, typically at least up to about fifty times. An ID connector typically comprises two or more tines defining an ID slot or slots into which a wire can be forced, the edges of the slot or slots piercing or displacing the insulation to establish conductive communication with the core or conductor of the wire, the wire at the same time being releasably secured to the connector by becoming compressed and retained in the slot or slots.

The ID connector typically comprises a portion capable of being secured in a hole in a board, for instance a circuit board, to enable wires to be connected to the board. The portion engageable with the board may simply function to mechanically fasten the connector to the board, in which case the connector functions as a wiring terminal, or it may be capable also of removably receiving a pin, for instance a pin of an electrical component such as an integrated circuit (IC) or reed relay, whereby the IC or other component can be removably secured to the board and conductively connected via such an ID connector or connectors, acting in this case as an ID socket or sockets, to a wire or wires connected to the socket or sockets.

Wires may be connected to ID connectors automatically or manually. Manual wiring is generally employed for "bread-boarding" or for low or moderate scale production. Manual wiring is generally performed with a wiring implement or tool generally known as a "wiring pen" because it has a body of generally similar dimensions to a pen and is held in a manner generally similar to holding a pen.

A variety of wiring pens are commercially available. Most or all of them comprise a pair of arms spaced from one another at a tip of the implement and capable of cooperating with one another to push an insulated wire into an ID slot of the connector to effect the desired connection. In use, the wire is typically guided to as to extend between the free ends of the two arms, being for example located in grooves in the free ends. The pen is then moved downwardly towards the connector to offer the wire up to the slot with the arms of the pen disposed on opposite sides of a portion of the connector bearing the slot.

The pen is then pushed towards the connector, still axially of the slot, so that the wire is pushed into and along the slot. When the wire is in place, the pen is removed by moving it in the opposite direction. The need to position the pen above and in alignment with the slot, and thereafter to move it towards and away from the slot in a direction axially of the slot, can be somewhat awkward.

The vertical up and down movement required to offer up and connect the wire to a connector is not a natural one to a hand used to using a pen. Furthermore, bearing in mind that the connectors are very small, the pen tends to obscure the user's view of the connector, which makes it difficult to offer up the wire properly to the slot.

According to the invention there is provided a wiring implement for conductively connecting an insulated wire to an ID connector, the implement comprising a pair of arms spaced from one another at a tip of the implement and capable of cooperating with one another to push an insulated wire into an ID slot of the connector to effect the connection, wherein one arm is fixed with respect to a body of the implement, the other arm is movable into and out of the body of the implement and is resiliently biassed out of the body of the implement so as to adopt, in a rest condition, a position in which its free end is disposed further from the body than that of the fixed arm, and the movable arm is provided with wire guide means guiding the wire to extend towards the fixed arm from a position beyond the free end of the fixed arm when the movable arm is in the rest condition, whereby the movable arm can be moved into a position in which the wire is positioned at the mouth of an ID slot and subsequent movement of the implement towards the connector will then cause retraction of the movable arm so that the free end of the fixed arm contacts the wire and pushes it into the slot.

With an implement in accordance with the invention, there is no need to move the implement axially of the slot to offer the wire up to the slot. Instead, the user can offer the wire up to the slot by means of a variety of different movements, for example in a more natural sideways or "writing" form of move ment. Possibly more importantly, due to the fact that, in the rest position, the free end of the fixed arm is spaced considerably above the free end of the movable arm, the user can readily observe the wire and mouth of the slot as they approach one another and is therefore readily able to visually monitor and control the operation of offering the wire up to the slot.

Further, if the resilient biassing is employed to allow the movable arm thereafter to move back to its rest position, the implement can be moved away from the connector in a variety of different convenient directions.

The wire guide means preferably comprises an aperture or hole formed in the movable arm. In this way, the wire extends in use out of a face of the movable arm adjacent to the fixed arm and the free end or "tail" of the wire can readily be positioned adjacent a slot of a connector. This process is simplified if, as is preferred, the aperture or hole is inclined in the sense that the end of the aperture on the face of the movable arm nearer the fixed arm is further from the body of the implement than the other end of the aperture.The use of wire guide means in the form of an aperture or hole in the movable arm offers excellent wire guidance in that the wire will readily and naturally tend to position itself where the user requires it, in marked contrast to some known wiring implements where it can be difficult to ensure that the wire is always correctly positioned.

The free end of the fixed arm is preferably configured in some manner as to assist in its trapping the wire as the free end of the fixed arm approaches the free end of the movable arm as the movable arm is extended into the body of the implement during the insertion process. Preferably, the free end of the fixed arm is of a generally triangular or like configuration having an apex in which the wire tends to remain during the above-described process.

The implement is preferably in the form of a "wiring pen", that is to say it has dimensions generally resembling those of a pen and can be held in the hand in a manner similar to a pen. However, it is believed that the invention may have more general applicability to other forms of hand-usable implement and may in fact apply more broadly to automatically operable implements.

If the implement is, as in the preferred embodiment described below, in the form of a wiring pen, the wire may be guided to the wire guide means along the body of the implement. The body may for example comprise an outer sleeve that fits over a barrel having a groove extending along it, the wire extending in the groove and being covered by the sleeve. The wire preferably emerges via an aperture or opening in the sleeve at or adjacent the end of the sleeve nearer the tip of the implement, from which it is fed to the wire guide means. The exposed portion of the wire between such aperture or opening and the wire guide means enables free travel of the wire to be controlled in that such portion of the wire can be contacted by the index finger and variation of the pressure of the index finger will vary the resistance to withdrawal of the wire.This can, for example, prevent loops or tangles caused by excessive wire withdrawal, which can cause problems in some prior implements.

The invention will now be further described, by way of illustrative and non-limiting example, with reference to the accompanying drawings, in which: Figure 1 is a perspective view of an ID socket; Figure 2 is a sectional side view of the socket of Fig. 1 taken along the line ll-ll in Fig. 1, and showing schematically a method of connecting a wire to the socket by means of a known form of wiring pen; Figure 3 is a partial perspective view of a wiring pen embodying the present invention, various internal components being shown in full for the sake of clarity; Figure 4 is a side view of the implement of Fig. 3, taken from the reverse side in Fig. 3; and Figures 5 and 6 are partial side views of the ID socket of Fig. 1 in the process of having a wire connected thereto by means of the implement of Figs. 3 and 4.

Fig. 1 of the drawings shows an insulation displacement (ID) socket 10 secured in place in a circuit board 12. The socket 10 comprises a wire receiving portion 14 to which one or more wires W may be connected on one face 1 6 of the board and a pin-receiving portion 1 8 into which a pin (not shown) of an electronic component, for instance an integrated circuit (IC), may be inserted from the other face 20 of the board.

The entire socket 10 is formed integrally from sheet beryllium-copper or phosphorbronze. A plurality of the sockets 10 may in fact be supplied still secured to a strip or bandolier (not shown) of such material by necks (not shown) which can be broken or cut, as required, to remove the sockets from the strip or bandolier for use. Such removal may be effected for instance by an automatic insertion machine operative to insert the sockets automatically into the board 1 2.

The wire-receiving portion 14 comprises a pair of tines 22, 24 defining a longitudinally extending slot 26 having a tapered outer end or mouth 28. In use, when the socket 10 is in place in the board 12, and in a manner described in detail hereinbelow, one or more insulated wires W can be inserted into the slot 26 so that the edges of the slot displace or pierce the insulation 27 of the wire and effect conductive communication with the core or conductor 29 thereof, the jamming of the wire into the slot 26 also serving to removably secure the wire in place.

The pin-receiving portion 1 8 is of generally cylindrical form and has a slot 30 extending along its entire length whereby its diameter can be altered by deforming it. The nominal diameter of the board 18 is slightly larger than that of a hole or aperture in the board 1 2 into which it is pushed from the face 1 6 of the board, whereby the resilient deformation of the portion 1 8 effected when it is pushed into the hole tends to hold it in place. To assist in holding it in place, protrusions (not shown) formed in the portion 1 8 penetrate the material of the board 1 2 during insertion and anchor the socket therein.Furthermore, stops 36 are formed in the portion 1 8 to ensure that the socket is pushed into the board to precisely the desired position. Resilient fingers (not shown) within the portion 1 8 resiliently and conductively engage the component pin when it is pushed therein.

The way in which a wire W can be inserted in the slot 26 by means of a known form of wiring implement or "wiring pen" will now be described with reference to Fig. 2. The implement comprises a generally pen-like body (not shown) having a pair of arms 40, 42 at its tip. The arms 40, 42 are spaced from one another with a gap 44 between them. With the aid of wire guide means (not shown), the wire W is arranged between the free ends thereof as shown in dotted lines in Fig. 2.

(The free ends of the arms 40, 42 are desirably provided with grooves (not shown) to accomodate the wire in the correct position).

The implement is then offered up to the connector, by moving it in a direction perpendicular to and towards the board 12, such that the wire W is positioned at the mouth 28 of the slot 26, the arms 40, 42 are on opposite sides thereof, and the arms 40, 42 (and thus the gap 44 between them) are aligned parallel with the axes of the tines 22, 24. (Bearing in mind that the socket 10 and the arms 40, 42 are very small and in particular considerably smaller than the diameter of the body of the wiring pen, this may be rather a difficult operation, bearing in mind in particular that the user may often be an occasional rather than a skilled user).The pen is then forced downwardly, keeping it aligned perpendicularly to the board 12, to push the wire W down into the slot 26. (The positions of the free ends of the arms 40, 42 and the wire W at an intermediate stage of this process are shown in dotted lines in Fig. 2). When the wire is pushed sufficiently home, the wiring pen is removed from the socket in the opposite direction and care must be taken to keep the direction of movement substantially perpendicular to the board 1 2 until the free ends of the arms 40, 42 clear the mouth 28 of the slot 26.The wiring pen is then moved horizontally to another conductor 10 on the board 1 2 and the same offering-up process, wire insertion movement and pen removal movement are effected; this sequence of operations being repeated to effect point-to-point wiring between conductors 10 on the board 1 2.

Figs. 3 and 4 show a wiring pen embodying the present invention. The wiring pen is, in a manner known per se, of a generally penlike form. It includes a body comprising a barrel 50 on which a sleeve 52 is slidably received. The barrel 50 has an end cap 54 that is externally knurled to simplify gripping with the fingertips. A pair of arms 56, 58 protrude from the tip of the pen. The arms 56 and 58 extend parallel to one another and are spaced apart by a distance thicker than the tines 22, 24 of the connector 10. The arm 56 is fixed with respect to the body of the pen.

The arm 58 is movable into and out of the body of the pen and is resiliently biassed out of the body of the pen by a spring 59 so as to adopt, in a rest condition, the position illustrated in Fig. 3, in which its free end is disposed further from the body than the free end of the fixed arm 56.

The free end of the movable arm 58 is provided with a cut out portion defining a pair of legs 60, the cut out portion providing a clearance around the socket 10 in a manner described below with reference to Fig. 6.

The free end of the fixed arm 56 is provided with a cut-out 62 of a generally triangular configuration whereby it acts as an anvil.

A hole 64 extending through the movable arm 58 acts as a wire guide means. A wire W is fed to the hole 64 to extend (as can best be seen in Figs. 5 and 6) outwardly from that face 66 of the arm 58 that is nearer the fixed arm 56. The hole 64 is preferably inclined in the sense shown, such that its end opening to the face 66 is nearer the free end of the arm 58 than its other end. The end of the hole 64 opening to the face 66 is so disposed as to be beyond the free end of the fixed arm 56 when the movable arm 58 is in its rest position. The other end of the hole 64 is preferably widened out as shown to simplify insertion of the wire W.

The wire W is fed to the hole 64 via a groove 68 (Fig. 4) extending along the barrel 50, the wire being laid in the groove 68 and emerging via a hole 70 in the barrel 52 where it extends (externally of the body of the pen) to the hole 54. The wire is fed to the end of the groove 68 remote from the tip of the implement from a reel (not shown). In a manner known in the art, the reel may be fitted to the end of the pen remote from the tip. However, this tends to make the pen rather unwieldy, whereby it is preferred that the reel not be mounted on the pen.

The index finger of the user can be positioned to rest on the exposed portion of the wire W between the holes 64 to 70 to control free travel of the wire by pessure thereon, so enabling wire withdrawal to be controlled, especially so as to prevent excessive withdrawal.

The manner of use of the pen of Figs. 3 to 6 will now be described. The pen is moved so that the "tail" of the wire W emerging from the end of the hole 64 at the face 66 of the movable arm 58 is offered up to the mouth 28 of the slot 26. Note that, because the free end of the arm 56 is well out of the way, there is no need for such movement to be effected in a direction perpendicular to the board 1 2. The pen can in fact be oriented in the correct position simply by moving it generally transversely of the tines 22, 24 until the face 66 abuts the tines. The user can thus make use of a reasonably natural movement in offering up the wire to the slot 26 andsince the fixed arm 56 is out of the way-can readily see that it is in fact correctly offered up.The user then presses the pen down towards the board 1 2. This tends to push the wire W into the slot 26. However, the force resisting such insertion will overcome the force provided by the spring 59 whereby the wire W will not in fact enter the slot 26 and the movable arm 58 will thus be pushed into the end cap 54. The net effect, from the point of view of the socket 10, is that the movable arm 58 and the wire W stay still and the fixed arm 56 moves downwardly towards the "tail" of the wire W. This process continues until, as shown in dotted lines in Fig. 5, the tail of the wire is caught by the triangular configuration 62 on the free end of the fixed arm 56 and is moved up it until it is positioned at the apex of the configuration.The free end of the fixed arm 56 then acts as an anvil and pushes the wire W down into the slot 26 to mechanically secure it in the slot and electrically connect it to the connector 10 in a manner known per se. Insertion of the wire W into the slot 26 stops when the free ends of the legs 60 on the movable arm 58 contact the face 1 6 of the board 1 2 on either side of the socket 10 and the movable arm 58 cannot be pushed further into the end cap 54: see Fig. 6. If the hand pressure on the wiring pen is then relaxed the body thereof will then spring up under the influence of the spring 59 and the fixed arm 56 will therefore automatically be spaced clear of the tines 22, 24 whereby the pen can then be moved away from the socket 10 again, if desired, generally transversely of the tines 22, 24.Thus, reliable and (if desired) removable point-to-point wiring can be effected between a plurality of the ID sockets 10 with great ease. The operation of the device is in fact so simple that someone with no prior experience and little or no specialist ability can learn to use it in a matter of minutes.

The hole 64 positions the free end or tail of the wire W as required, thereby minimising the possibility of the wire wandering away from its desired position.

The wiring pen described above can be used for wiring between other ID connectors than the ID socket 10 described above by way of example. For example, it can be used for wiring to an ID terminal which is generally similar to the socket 10 except that the portion 1 8 does not serve as a pin-receiving portion but simply serves to stake it in a board or to fix it to some other surface. Further, with any attendant minor changes in the geometry of the pen, the pen can be used for wiring to a variety of other types of ID connectors having a variety of numbers of tines and slots, connectors of such different types being known in the art.

Claims (9)

1. A wiring implement for conductively connecting an insulated wire to an insulation displacement (ID) connector, the implement comprising a pair of arms spaced from one another at a tip of the implement and capable of cooperating with one another to push an insulated wire into an ID slot of the connector to effect the connection, wherein one arm is fixed with respect to a body of the implement, the other arm is movable into and out of the body of the implement and is resiliently biassed out of the body of the implement so as to adopt, in a rest condition, a position in which its free end is disposed further from the body than that of the fixed arm, and the movable arm is provided with wire guide means for guiding the wire to extend towards the fixed arm from a position beyond the free end of the fixed arm when the movable arm is in the rest condition, whereby the movable arm can be moved into a position in which the wire is positioned at the mouth of an ID slot and subsequent movement of the implement towards the connector will then cause retraction of the movable arm so that the free end of the fixed arm contacts the wire and pushes it into the slot.

2. A wiring implement according to claim 1, wherein the wire guide means comprises an aperture or hole formed in the movable arm.

3. A wiring implement according to claim 2, wherein the aperture or hole is inclined in the sense that an end of the aperture or hole on a face of the movable arm proximate the fixed arm is further from the body of the implement than the other end of the aperture or hole.

4. A wiring implement according to claim 1, claim 2 or claim 3, wherein the free end of the fixed arm is configured so as to assist in its trapping the wire as the free end of the fixed arm approaches the free end of the movable arm as the movable arm is extended into the body of the implement during the wire insertion process.

5. A wiring implement according to claim 4, wherein the free end of the fixed arm is of a generally triangular or other configuration having an apex in which the wire tends to remain during the wire insertion process.

6. A wiring implement according to any one of the preceding claims, wherein the implement in the form of a wiring pen and the body of the implement is provided with means for guiding the wire to the wire guide means along the body of the implement.

7. A wiring implement according to claim 6, wherein the body of the implement comprises a sleeve that fits over a barrel having a groove extending along it, whereby the wire can extend along the groove and be covered by the sleeve.

8. A wiring implement according to claim 7, including an aperture or opening in the sleeve at or adjacent an end of the sleeve nearer the tip of the implement, through which aperture or opening the wire can be fed from the groove to the wire guide means.

9. A wiring implement substantially as herein described with reference to Figs. 3 to 6 of the accompanying drawings.