GB2190801A - Electrical wiring apparatus - Google Patents

Abstract

Electrical wiring apparatus comprises a board (10) through which project terminals (12) each surrounded by a resilient sleeve (14, 26). The terminals (12) are positioned to enable the legs (16) of an integrated circuit chip (18) to be inserted between corresponding sleeves (14) and terminals (12), each sleeve (14) resiliently holding the corresponding chip leg in electrical contact against the respective terminal (12). Connecting wires (20) can be inserted between selected sleeves and terminals, or connected directly to terminals (Fig. 3), so that wiring between components and chips can be carried out from the same side of the board (10). Alternatively a strip (26) instead of separate sleeves (14) is used. <IMAGE>

Description

SPECIFICATION Electrical wiring apparatus Field of the Invention This invention relates to electrical wiring apparatus.

Background to the Invention When making eletrical circuits for prototype or educational purposes, components such as integrated circuit chips are mounted on one side of a board (eg a printed circuit board) and electrical wiring is connected (eg by wrapping or soldering) to appropriate terminals on the other side of the board. Each integrated circuit chip has a number of projecting pins or legs which are electrically connected to individual terminals on one side of the board. Successful wiring requires that the same terminals projecting through the other side of the board are correctly identified and correlated with the terminals to which the chip legs are connected, so that the appropriate electrical connections are made to the correct legs of the integrated circuit chip.This need to identify particular terminals on the reverse side of the board from that carrying the integrated circuit chip represents a problem which the present invention aims to overcome.

Summary of the Invention According to the invention electrical wiring apparatus comprises a board, a plurality of metal terminals projecting from one side of the board in at least two parallel rows so as to register with the projecting legs of an integrated circuit chip, and retention means which engage the metal terminals and which are operative resiliently and detachably to hold the chip legs in electrical contact against the respective terminals to which electrical connecting wires can be detachably connected from said one side of the board.

The board may be a printed circuit board providing circuit paths electrically interconnecting certain pins, or the board may be a perforated board through which the terminals are inserted.

The retention means may be individual resilient sleeves which surround the metal terminals, which are conveniently in the form of cylindrical metal studs or alternatively the retention means for each row of terminals may be an integrally moulded block or strip of plastics material with formations for receiving or embracing the terminals. The formations may be a plurality of spaced through bores at positions corresponding to the terminals in a row thereof to enable the block or strip to be located on the terminals with each terminal projecting into a corresponding bore. Alternatively, the formations may be in the form of pairs of resilient tabs, each pair embracing respective sides of a corresponding terminal so that the legs of a chip can be resiliently and detachably held between the tab and the terminal.

Each terminal may project proud of the retention means to provide a projecting terminal end around which the electrical connecting wires can be wrapped to provide the necessary electrical connections. Alternatively, the retention means may be operative not only to hold the chip legs in electrical contact with the respective terminals but also resiliently and detachably to hold the electrical connecting wires against selected terminals, with the wires in electrical contact with the selected terminals.

The invention will now be further described by way of example with reference to the accompanying drawings in which: Figure 1 is a perspective view showing how an integrated circuit chip is connected by resilient sleeves to terminals carried by a board, in accordance with the invention, Figure 2 is a sectional view through a chip mounted in position on a board, and showing additional electrical connecting wires, Figure 3 is a view similar to that of Figure 2 but showing a modified construction, Figure 4 is a fragmentary perspective view showing an alternative to the sleeves of Figures 1 to 3, and Figure 5 is a sectional view showing an assembly using the modification of Figure 4.

Referring to Figure 1, part of a printed circuit board 10 has two rows of metal pins or cylindrical studs forming terminals 12 projecting from one side of the board 10. Each of the terminals 12 is surrounded by a short length of plastics sleeving 14 which is resilient and electrically insulating. The sleeves 14 are preferably made of silicone rubber. The terminals 12 are arranged in two parallel rows so as to register with the projecting legs 16 of an integrated circuit chip 18.

Figure 2 shows how the chip 18 is mounted on the printed circuit board 10, with each leg 16 being inserted between a corresponding terminal 12 and the associated sleeve 14. The resilience of the sleeve 14 holds the leg 16 against the terminal 12, not only to hold the chip 18 in position, but also to provide effective electrical interconnection between each leg 16 and the corresponding terminal 12.

To wire the chip 18 into an electrical circuit constructed on the board 10, electrical connecting wires such as those indicated at 20 in Figure 2 have their stripped ends inserted between selected terminals 12 and the corresponding sleeves 14, in each case the wire 20 being pushed into the sleeve at a location on the opposite side of the terminal 12 from the leg 16. Figure 2 shows an electrical component such as a capacitor or resistor 22 connected to one of the wires 20.

It will be appreciated that a circuit board having a large number of terminals 12 may be used to support several chips such as chip 18, the chip legs being appropriately intercon nected with one another and with other electrical circuit components by means of wires 20.

In the modification of Figure 3, the chip legs 16 are again inserted between the sleeves 14 and the terminals 12, but in this case each terminal 12 projects upwardly beyond the sleeve 14 to provide a projecting end 24 around which the connecting wires 20 are wrapped, so as to provide electrical intercon nection between the wires 20 and the legs 16 of the chip 18.

Figure 4 shows a fragmentary view of a moulded strip 26 of plastics material which may be used as an alternative to the sleeves 14 previously described. The strip 26 has a grid-like frame 28 from which project pairs of tabs 30. The tabs are positioned such that when the strip 26 is placed over a row of terminals 12 each pair of tabs 30 resiliently engages a corresponding terminal 12, with the latter projecting through one of the rectangular apertures 32 in the grid-like frame 28, as shown in Figure 5. It will be appreciated that one strip 26 is provided for each row of terminals 12.

The legs 16 of the chip 18 are inserted between the tabs 30 and the terminals 12, the tabs 30 resiliently holding the legs 16 against the terminals 12. Connecting wires such as 20 can be inserted between selected terminals 12 and the opposite tab 30, as illustrated in Figure 5, both the legs 16 and the wires 20 extending through the rectangular apertures 32 in the grid-like frame 28.

Instead of being circular in cross-section, the terminals 12 may be square or rectangular in cross-section shape, the corners of which tend to assist retention of wrapped wire.

In all of the embodiments the chip legs 16 are resiliently and detachably held against the terminals 12, as are also the wires 20. Hence, circuits can be made and altered using the same components, a facility which is most useful for making prototype circuits or for making circuits for educational purposes. Also, it will be noted that all assembly of circuit components is carried out from the same side of the board 10, making it easy to check that the wires 20 are connected to the correct chip legs 16.

Claims (10)

1. Electrical wiring apparatus comprising a board, a plurality of metal terminals projecting from one side of the board in at least two parallel rows so as to register with the projecting legs of an integrated circuit chip, and retention means which engage the metal terminals and which are operative resiliently and detachably to hold the chip legs in electrical contact against the respective terminals to which electrical connecting wires can be detachably connected from said one side of the board.

2. Apparatus according to claim 1, wherein the board is a printed circuit board providing circuit paths electrically interconnecting certain terminals.

3. Apparatus according to claim 1, wherein the board is a perforated board through which the terminals are inserted.

4. Apparatus according to any of the preceding claims, wherein the retention means are individual resilient sleeves which surround the metal terminals.

5. Apparatus according to any of claims 1 to 3, wherein the retention means for each row of terminals is an integrally moulded block or strip of plastics material with formations for receiving or embracing the terminals.

6. Apparatus according to claim 5, wherein the formations are a plurality of spaced through bores at positions corresponding to the terminals in a row thereof to enable the block or strip to be located on the terminals with each terminal projecting into a corresponding bore.

7. Apparatus according to claim 5, wherein the formations are in the form of pairs of resilient tabs, each pair embracing respective sides of a corresponding terminal so that the legs of a chip can be resiliently and detachably held between the tab and the terminal.

8. Apparatus according to any of the preceding claims, wherein each terminal projects proud of the retention means to provide a projecting terminal end around which the electrical connecting wires can be wrapped to provide electrical connections.

9. Apparatus according to any of claims 1 to 7, wherein the retention means are operative not only to hold the chip legs in electrical contact with the respective terminals but also resiliently and detachably to hold the electrical connecting wires against selected terminals, with the wires in electrical contact with the selected terminals.

10. Electrical wiring apparatus constructed and arranged substantially as herein particularly described with reference to the accompanying drawings.