US3764954A

US3764954A - Mounting for circuit boards

Info

Publication number: US3764954A
Application number: US00248039A
Authority: US
Inventors: D Saunders
Original assignee: APW Electronics Ltd
Current assignee: APW Electronics Ltd
Priority date: 1971-04-28
Filing date: 1972-04-27
Publication date: 1973-10-09
Anticipated expiration: 1990-10-09
Also published as: GB1332565A; DE2221144A1

Abstract

Apparatus for mounting circuit boards comprising an edge connector having a plurality of cavities containing contacts to mate with plug-in contacts on the end of a circuit board and a pair of opposed guide channels for receiving the edges of the circuit board, each guide channel extending at right angles to the edge connector and having at its end a tongue fitted into and located both vertically and horizontally by vacant contact cavities in the edge connector.

Description

. England Filed:

UnitedSta'tes Patent 1 1 I 1111 1 3,764,954

Saunders 1 51 Oct. 9, 1973 [5 MOUNTING FOR CIRCUIT BOARDS 3,008,113 11/1961 Johnson aw/171.114

[751' Inventor ver'eksaundemwimbome, 223132? 31322 22:12:11;;;;;...........;;;;;212m

England [73] Assignee: Vero Electronics Limited, Eastleigh, Primary Examiner joseph H McGlynn Attorney-Watson et al.

[22] Apr. 27, 1972 [21] Appl. No.: 248,039 [57] ABSTRACT [30] Foreign Application Priority Data Apparatus for mounting circuit boards cornprising an A 28 1971 G t 11 851/71 edge connector having a plurality of cavities containtea n am ing contacts to mate with plug-in contacts on the end of a circuit board and a pair of opposed guide chan- 339/65 nels for receiving the edges of the circuit board, each [58] d 65 66 176 guide channel extending atright angles to the edge connector and having at its end a tongue fitted into and located both vertically and horizontally by vacant I UNITE r E S :;qrENTS contact cavities in the edge connector. 3,193,791 7/1965 Beck et al 339/65 Claims, Drawing Figures 1 5 I 26' 12 1 5214 I 2] .-;.B

10 2 Z :s 22:: "2 :2 2:22: 2 1 1 a 19 88 32333 8 1: 38 88332 a: a o a: 22:: z: a 1 as 55 a an 2% a 19 4 22 21 26' I g 11 10 12 25 I5 PATENTEU OCT 9 I975 sum 1 UF 3 0 0 0 O O 0 O O 0 O 0 0 O O 0 O 0 0 0 0 0 0 MOUNTING FOR CIRCUIT BOARDS This invention relates to apparatus for mounting circuit boards of the type comprising at least one pair of opposed guide channels, for receiving the opposite side edges of a circuit board, and an edge connector disposed at right angles to the guide channels and having a plurality of cavities containing contacts for cooperation with plug-in contacts on the end of the circuit board slid endwise into the guide channels. Normally such apparatus includes a number of spaced pairs of opposed guide channels and a corresponding number of edge connectors associated with them.

Such edge connectors are mass produced either in continuous strip form, from which individual connectors can be cut to suit the requirements of a particular installation, or as individual units having at their ends ears for attachment to a frame intended for accommodation of the circuit boards, the edge connectors containing contacts in all cavities or only in those in which contacts are required by a customer.

Hitherto the practice has been to attach the edge connectors and the guide channelsindependently to the frame of the apparatus. Since various tolerances must be allowed in the interests of manufacture of the frame at an acceptable price, this can lead to inaccurate location of the contacts on the circuit boards with respect to the contacts in the cavities of the edge connectors. The object of this invention is to ensure accurate alignment in both the horizontal and the vertical plane of one or each circuit board and the associated edge connector.

The invention accordingly provides apparatus for mounting circuit boards comprising an edge connector having a plurality of cavities containing contacts to mate with plug-in contacts on the end of a circuit board and a pair of opposed guide channels for receiving the edges of the circuit board, each guide channel extending at right angles to the edge connector and having at its end a tongue fitted intoand located both vertically and horizontally by vacant contact cavities in the edge connector.

' In its preferred form the apparatus comprises a series of spaced parallel edge connectors, each having a plurality of cavities containing contacts to mate with plugin contacts on the end of a circuit board, and a series of pairs of opposed guide channels for receiving the side edges of circuit boards to be slid endwise into engagement with the edge connectors, each pair of guide channels extending at right angles to an edge connector with tongues on the ends'of the guide channels fitted into and located by vacant contact cavities in the edge connector.

Since the inner ends of the guide channels are precisely located by the cavities in the edge connectors into which they are fitted, correct plug-in connection of the circuit boards to the edge connectors is assured. The outer ends of the guide channels can be connected to the frame of the apparatus in any convenient way since minor errors in alignment of these outer ends is immaterial.

The edge connectors have contact tails projecting from them at the side remote from the circuit boards and it is often desired to mount the edge connectors on alarge single or multiple layer circuit board. Such a large circuit board is commonly known as a mother board and performs the function, in one or a multiplicbe mounted on the mother board independently from the frame of the apparatus and the invention enables the mechanical alignment problems to be simply and easily resolved. A further advantage is that the mother board with the edge connectors fitted can be soldered and any additional wiring can be carried out before the assembly is mounted in the frame.

The invention therefore, in addition to ensuring correct location of the inner ends of the guide channels with respect to the edge connectors, has the advantage that all operations involved in connecting the contact tails of a number of edge connectors to a mother board and establishing the necessary electrical connections can be carried out prior to assembly of the edge connectors in the apparatus, including the guide channels, of which they are to form part.

Certain embodiments of the invention will now be described in detail, by way of example with reference to the accompanying drawings, in which:

FIG. '1 is a vertical section through an assembled framework for the reception of circuit boards,

FIG. 2 is a section on the line II-II in FIG. 1,

FIG. 3 is a section on the line llI--III in FIG. 1,

FIG. 4 is a verticalsection through the rear part of a modified. framework,

FIG. 5 is a similar view showinganother modified construction,

FIGS. 6 and 7 are perspective views looking in different directions and showing a guide channel,

FIG. 8 is a. perspective view showing partof a modified guide channel,

FIG. 9 is a similar view illustrating a further modification, and

FIG. 10 is a view illustrating the front end of a double guide channel.

In the construction illustrated in FIGS. ll.3, the

1 framework includes a pair of end plates 10,- one only of which is illustrated, joined by opposed pairs of front and rear

longitudinal members

11 and 12 respectively.

The members 12 carry a series of spaced parallel edge connectors 13, which are held in position by clamping strips 14 attached by bolts 15 to the members 12. Each edge connector 13 has rearwardly extending contact tails 16, to which circuit connections are established by wiring, by attachment. of the tails to a mother board as described above or in any other convenient way. The edge connector has equally spaced contact cavities 17 (FIG. 3), some of which contain female spring contacts 18 for cooperation with male contacts 19 (FIG. 1) on the edge of a circuit board 20, are slid endwise into a pair of opposed guide channels 21.

As shown most clearly in FIGS. 6 and 7, each guide channel 21 has a base 22 and two integral sides 23 forming a groove 24 for the accommodation of the side edge of a circuit board. At one end the base 22 is extended to form a tongue 25, which is fitted into a vacant contact cavity 17 in an edge connector 23, as shown most clearly in FIG. 3, to locate the guide channel with respectto the edge connector. At its other end the guide channel 21 has a forked projection 26 which, after the tongue 25 has been located in an edge connector cavity 17, is snapped into a hole in a frontmember 11 to connect the guide channel to the frame as shown in FIG. 1.

The guide channels 21 are thus located in opposed pairs, with their grooves 24 facing inwardly to receive the edges of circuit boards 20 and with their rear ends accurately located with respect to the edge connectors 13. Accordingly a circuit board may be slid endwise into a pair of guide channels to ensure effective contact of its contacts 19 with the contacts 18 in the cavities 17 of an edge connector. Since one end of each guide channel is located in the edge connector, accurate alignment of the terminals 19 on the circuit board and the contacts 18 in the connector is ensured. Owing to accurate alignment only sufficient force to overcome the combined force of the contacts 18 in the edge connector on the contacts 19 on the plug-in circuit board has to be used on insertion of the plug-in circuit board into the edge connector.

While in FIG. 1 the edge connectors 13 are shown attached to the frame by the clamping strips 14 and the bolts 15, such connection is not essential. In suitable cases the edge connectors may be held merely by the tongues 25 on the guide channels.

In cases when the edge connectors 13 are supplied with contacts 18 in all cavities 17, these contacts are of course removed from the cavities which are to receive the tongues 25.

FIGS. 4 and 8 show a modified form of guide channel 121 of I-I-sectio'n and having grooves 24 at both sides. This form of guide channel can be used when it is desired to subdivide the depth of the frame so that it may accommodate upper and lower rows of narrower circuit boards. As shown in FIG. 4, the tongue.25 of the double guide channel 121 is again fitted into a vacant contact cavity in an edge connector 13. The circuit boards in the upper row are introduced between the upper guide channel 21 and the double guide channel 121 and the circuit boards of the lower row are introduced between the double guide channel 121 and the lower guide channel 21.

In the further modification shown in FIGS. 5 and 9, a double guide channel 221 has two tongues 225 which are fitted into vacant contact cavities in two aligned edge connectors 13 to provide two tier accommodation for circuit boards. To increase flexibility, the guide channel 221 has at each side a longitudinal slot 30 at its rear end.

The front end of each

double guide channel

121, 221 shown in FIGS. 4 and 5 is attached to a frame member 31 (FIG. 10) by a stud 32 passed through holes in the frame member and in a lug 33 on the guide channel.

What I claim as my invention and desire to secure by Letters Patent is 1. Apparatus for mounting circuit boards comprising a frame, a series of spaced parallel edge connectors attached at opposite ends to said frame and each having a plurality of identical cavities containing removable contacts to mate with plug-in contacts on the end of a circuit board, and a series of pairs of opposed guide channels having in one face only grooves for receiving the side edges of circuit boards to be slid endwise into engagement with the edge connectors, each pair of guide channels extending at right angles to an edge connector, a tongue at one end fitted into and located by a vacant contact cavity in an edge connector and being attached at its other end to the frame, the tongues on each pair of guide channels being fitted into vacant cavities in the same edge connector.

2. Apparatus as claimed in claim 1, in which each guide channel comprises a base carrying the tongue and integral sides defining the groove for reception of the edge of a circuit board.

3. Apparatus as claimed in claim 2, in which each said guide channel has at the end remote from the tongue a projection engaging a hole in said frame.

4. Apparatus as claimed in claim 1, which includes guide channels of H-section and has grooves at both sides for accommodating the edges of circuit boards.

5. Apparatus as claimed in claim 4, in which each said guide channel of an H-section has two tongues for location in vacant contact cavities in aligned edge con-

Claims

1. Apparatus for mounting circuit boards comprising a frame, a series of spaced parallel edge connectors attached at opposite ends to said frame and each having a plurality of identical cavities containing removable contacts to mate with plug-in contacts on the end of a circuit board, and a series of pairs of opposed guide channels having in one face only grooves for receiving the side edges of circuit boards to be slid endwise into engagement with the edge connectors, each pair of guide channels extending at right angles to an edge connector, a tongue at one end fitted into and located by a vacant contact cavity in an edge connector and being attached at its other end to the frame, the tongues on each pair of guide channels being fitted into vacant cavities in the same edge connector.

5. Apparatus as claimed in claim 4, in which each said guide channel of an H-section has two tongues for location in vacant contact cavities in aligned edge connectors.