GB2376802A

GB2376802A - Circuit board assembly

Info

Publication number: GB2376802A
Application number: GB0106093A
Authority: GB
Inventors: Matthew Alyn Harries
Original assignee: Matsushita Electronics Corp
Current assignee: Panasonic Holdings Corp
Priority date: 2001-03-13
Filing date: 2001-03-13
Publication date: 2002-12-24
Also published as: GB0106093D0

Abstract

A circuit board assembly comprises a substantially flat circuit board substrate 10 on which the electrical components are mounted and a peripheral support frame or chassis 11. One side of the chassis 11 is provided with a plurality of sockets 14 each containing a resiliently flexible pawl for captively receiving respective projections 16 disposed along one edge of the substrate 10. The substrate 10 can thus be quickly and easily fitted to the chassis 11 without the need for screws.

Description

CIRCUIT BOARD ASSEMBLY This invention relates to a circuit board assembly. Circuit boards are generally mounted inside housings by means of screws passed through an aperture in the circuit board substrate. A disadvantage of this arrangement is that it is difficult and time consuming to install or remove the circuit board from the housing.

We have now devised a circuit board assembly which alleviates the above-mentioned problem.

In accordance with this invention there is provided a circuit board assembly comprising a substantially flat circuit board substrate on which at least one electrical component is mounted and a support member, the support member comprising a socket arranged to receive an edge of the substrate and means within the socket for engaging the substrate.

In use, the circuit board is mounted to the support member by transposing the substrate laterally of itself such that an edge thereof is engaged within the socket.

In this manner the circuit board can easily and quickly be mounted to the support member.

Preferably a plurality of sockets are provided on the support member for engaging the edge of the substrate.

Preferably the support member comprises a resiliently flexible pawl which is biased into the socket for engaging a formation on the substrate.

Preferably the substrate comprises an aperture which receives a head of the pawl.

Preferably the support member is formed as a one-piece moulding of plastics material.

Preferably the socket comprises an entrance end, through which the projection is inserted, the head of the pawl comprising a front surface which is inclined away from the entrance end and into the socket, a rear surface of the head lying substantially normal to the axis of insertion of the socket.

In use, when the substrate is transposed towards the socket, the outer end of the projection abuts the inclined face of the pawl, thereby deflecting it out of the socket and allowing the projection to enter. The pawl then snap engages with the formation on the substrate, once it has been inserted sufficiently far into the socket.

Preferably the support member comprises a frame to which the circuit board is mounted, said formation (s) being provided along one side of the frame.

Preferably the frame is detachably mounted to a housing portion of the assembly.

The substrate may comprise a projection on said edge which is received by said socket.

Embodiments of this invention will now be described by way of examples only and with reference to the accompanying drawings, in which: FIGURE 1 is a perspective view of an embodiment of printed circuit board assembly in accordance with this invention, showing how the printed circuit board is engaged with the support member ; FIGURE 2 is a plan view of the assembly of Figure 1; FIGURE 3 is a sectional view along the line III-III of Figure 2, once the circuit board and support member are engaged; and FIGURE 4 is a perspective view of a alternative embodiment of printed circuit board assembly in accordance with this invention, showing how the printed circuit board is engaged with the support member Referring to Figures 1 to 3 of the drawings, there is shown a printed circuit board assembly for a television receiver. The assembly comprises a large printed circuit board 10 on which a plurality of electrical and electronic components (not shown) are mounted.

The circuit board 10 is so large and the components thereon are so heavy that the board 10 needs to be mounted to

a support member or so-called chassis 11 in the form of a frame, in order to support the board 10.

The chassis 11 comprises a one-piece moulding of plastics material having parallel side and end members 12 and cross members 13 extending between opposite side and/or end members 12.

Hitherto, printed circuit boards have been mounted to the chassis by passing screws into the chassis through apertures formed around the sides of the printed circuit board.

A disadvantage of this arrangement is that it is difficult and time consuming to fit these screws, particularly if the circuit board is large. Another disadvantage is that some of the screws may be difficult to access once the chassis has been installed within the television receiver.

In accordance with this invention, one end member 12 of the chassis 11 is formed with integral upstanding formations 14, which each define a passageway 15 for receiving a projecting tab 16 formed on one side edge of the printed circuit board 10.

The formations 14 each comprise an elongate top wall 17 lying parallel to, but spaced above, an upper flat surface of the end member 12 of the chassis 11. The elongate top wall 17 extends axially of the end member 12 of the chassis 11. Opposite ends of the top wall 17 are connected to the end member 12 by respective end walls 18. The outer side of the top wall 17 is also connected to the end member 12 by an outer side wall which co-extends with the outer side wall 19 of the end member 12 of the chassis 11. The inner side of the top wall 17 is not connected to the end member 12 of the chassis 11, thereby defining an opening into the passageway 15, which extends under the top wall 17 and between the end walls 18 of the formation 14.

A pair of parallel slots 20 extend transverse the top wall 17 of the formation 14 from the inner side thereof, to define a pawl 21 disposed intermediate opposite ends of the top

wall 17.

The free end of the pawl 21 comprises an enlarged head 22 which projects into the passageway 15. Preferably the bottom wall of the passageway 15 is left open to enable the formation 14 to be moulded using conventional moulding techniques.

An aperture 23 is formed in the tab 16 on the printed circuit board 10, for receiving the head 22 of the pawl 21.

In use, the printed circuit board 10 is fitted to the chassis 11 by transposing the board 10 laterally of itself until the tabs 16 thereon enter the passageways 15 of respective formations 14. The outer edge of each tab 16 abuts the head 22 of the pawl 21 during insertion into the passageway, thereby causing the pawl 21 to deform sufficiently such that the head 22 thereof is removed from the passageway 15 and thus allowing the tab 16 to be inserted further into the passageway 15.

Once the tab 16 has been inserted sufficiently far into the passageway, the head 22 of the pawl 21 enters the aperture 23 under the resilient bias of the pawl 22 and engages the printed circuit board 10.

Referring to Figure 4 of the drawings, there is shown an alternative embodiment of printed circuit board assembly for a television receiver and like parts are given like reference numerals.

In this embodiment, the side walls 18 of the formation and the projection on the printed circuit board 10 are omitted, such the straight edge of the printed circuit board 10 can be inserted into the passageway 15, with the pawl 21 being arranged to engage an aperture 23 formed inwardly of the side edge of the printed circuit board 10.

A printed circuit board assembly in accordance with this invention enables one edge of the printed circuit board to be quickly and easily fitted to the chassis 11 without the need for screws.

Claims

Claims 1. A circuit board assembly comprising a substantially flat circuit board substrate on which at least one electrical component is mounted and a support member, the support member comprising a socket arranged to receive an edge of the substrate and means within the socket for engaging the substrate.
2. A circuit board assembly as claimed in claim 1, in which a plurality of sockets are provided on the support member for engaging the edge of the substrate.
3. A circuit board assembly as claimed in claim 1, in which the substrate engaging means comprises a resiliently flexible pawl which is biased into the socket for engaging a formation on the substrate.
4. A circuit board assembly as claimed in claim 3, in which the substrate comprises an aperture which receives a head of the pawl.
5. A circuit board assembly as claimed in claims 3 or 4, in which the socket comprises an entrance end, through which the projection is inserted, the head of the pawl comprising a front surface which is inclined away from the entrance end and into the socket, a rear surface of the head lying substantially normal to the axis of insertion of the socket.
6. A circuit board assembly as claimed in any preceding claim, in which the support member is formed as a one-piece moulding of plastics material.
7. A circuit board assembly as claimed in any preceding

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claim, in which the support member comprises a frame to which the circuit board is mounted, at least one socket being provided along one side of the frame
8. A circuit board assembly as claimed in claim 7, in which the frame is detachably mounted to a housing portion of the assembly.
9. A circuit board assembly as claimed in claims 7 or 8, in which the substrate comprises a projection on said edge which is received by said socket.
10. A circuit board assembly substantially as herein described with reference to Figures 1 to 3 or Figure 4 of the accompanying drawings.