GB2230649A

GB2230649A - Guide tray for circuit boards

Info

Publication number: GB2230649A
Application number: GB8927261A
Authority: GB
Inventors: Rafael Rodriguez Prados
Original assignee: Telefonica de Espana SA; Telefonica Nacional de Espana SA
Current assignee: Telefonica SA
Priority date: 1989-04-21
Filing date: 1989-12-01
Publication date: 1990-10-24
Anticipated expiration: 2009-12-01
Also published as: PT8095Y; CN2053837U; FR2646314A3; NO894868D0; BE1003895A3; NO894868L; CA1320593C; MA21604A1; GB8927261D0; TNSN89141A1; ES1010281U; NL8903184A; PT8095U; ES1010281Y; IT8921515V0; FR2646314B3; IT216794Z2; GB2230649B; JPH02137087U; LU87637A1

Abstract

A guide tray for receiving the edges of printed circuit boards comprises a generally rectangular sheet member with a plurality of apertures (6) therein. The apertures are rectangular but with one sloped side (2) towards the lateral edge of the tray. The apertures are separated by guide channels (1) of trapezoidal cross-section, and a rib (3) extending along the longitudinal axis of symmetry of the tray, the apertures being disposed to each side of the rib. The sloped sides of the apertures form flared or converging mouths to the guide channels (1), which serve to guide circuit boards into the channels. The lateral edges of the tray have stepped flanges (4) with protrusions (5) for reception in slots in a support frame. The symmetry of the tray means that it can be used interchangeably at either side of the boards. <IMAGE>

Description

Guide Tray for Circuit Boards This invention relates to a guide tray for printed circuit boards, provided to enable to insertion of circuit boards into their respective installed positions of use.

This is of particular application in telecommunications or other electronic fields where circuits include large numbers of identical or similar components which need to be inspected and replaced with ease.

There are already known several devices for guiding printed circuit boards or plates to ease their insertion into their respective positions of use and for connection into the circuit.

Nevertheless, they do not have, in any of the various versions, the features required to facilitate the initial insertion of the printed circuit board into the guide itself or for ease of assembly and economy.

Furthermore, in presently known devices of this kind, it is not possible to effect good ventilation of the printed circuit boards, thus hinering dissipation of the heat generated by the circuits.

An object of this invention is to provide a circuit board guide tray with all the features needed to ease initial introduction of the boards to the guide, which is easy to assemble, and is economical, which is designed so that it may be used in alternative orientations for opposite edges of the boards. It should also be provided with the features which can enable it to provide good ventilation.

The present invention accordingly provides a guide tray for printed circuit boards, comprising a generally rectangular thin web, characterised in that the web has a plurality of apertures in the shape of rectangles with one sloped end, the apertures being arranged in two rows which are symmetrical with regard to the longitudinal axis of the tray, a series of channels between the apertures constituting guide means, and a further channel forming a reinforcement for the tray.

The channels forming guide means for the edges of printed circuit boards may be of trapezoidal cross-section, e.g. with the walls of the channel diverging upwardly, to ease entry of the board edges into the guide channels.

The perforations preferrably form the greater part of area of the tray, and constitute a ventilation means for the circuit boards when installed.

The symmetrical arrangement of the apertures in the tray allows it to be used in alternative orientations, for receiving either the upper or lower edges of the boards.

The edges of the tray may be formed as or provided with a Z-sectioned flange, which enables the tray to be slid into a supporting frame with a suitable slot or slots. The flanges may be provided with a plurality of protrusions, in the form for example of dimples or mounds, which allow adjustment of t the tray to a receiving slot with a slight pressure.

A preferred embodiment of guide tray for circuit boards according to the invention will now be described by way of example, with referrence to the accompanying drawings, wherein: Fig. 1 is a plan view of a guide tray according to the invention; Fig. 2 is an end view of the tray from below in Fig. 1: Fig. 3 is an enlarged sectional view on the line A-A of Fig. 1; Fig. 4 is an enlarged sectional view on the line B-B of Fig. 1; and Fig. 5 is an enlarged sectional view of an edge of the tray, received in a slot in a frame member.

As shown in the drawings, a guide tray for the edges of printed circuit boards, according to the present invention, comprises a generally rectangular member of thin sheet material, which has been e.g. stamped and drawn, or otherwise worked to provide the required features.

The tray has aplurality of elongate substantially rectangular apertures 6, with sloped ends to form trapezoidal cut outs. The apertures 6 are arranged in two symmetrical rows, one to each side of a cental longitudinal dividing rib 3, which as in Fig. 4, is a channel sectioned member of trapezoidal, or diverging trough shape, cross-section. This rib marks the longitudinal axis of symmetry of the tray.

The apertures 6 not only considerably reduce the weight of the tray (the occupy much more than half of the surface area of the tray), but also provide means by which ventillation air may be circulated between the circuit boards when the latter are in position and being used. Air passing through the apertures will flow over the surfaces of the boards, thus helping to dissipate heat generated by the circuits.

The strips 1 separating adjacent apertures are formed as trapezoidal, or divering trough shaped channels, and these provide the actual guide channels to receive the board edges, as is shown in Fig. 3. The apertures 6 are surrounded by fences, which define the channels 1 and 3, and the sloped ends of the apertures provide flared or convergent inlets for the guide channels 1, presented towards the latteral sides of the tray, which guide the leading corners of boards, inexactly presented for insertion, towards and into the respective guide channels 1, without need for manual guidance to the slot, so that the insertion operation becomes easier and quicker.

The central rib 3 also acts as a reinforcement to the structure of the tray.

The latteral edges, 4, of the tray, which are symmetrical with regard to the longitudinal axis of the tray, are each provided with a flange, which may be regarded as stepped, Zsectioned, or providing two opposed rightangles. This flange can be received in a slot in a frame member 7. The flanges are each also provided with a plurality of bumps, dimples or protrusions 5, which provide a reslient tight fit of the flange in the slot, which avoid motion or vibration during operation and use of the equipment.

The symmetry of the apertures 6 with regard to the longitudinal axis defined by rib 3, enables the tray to be equally useful for retaining the top edges or bottom edges of the circuit boards, i.e. it is not necessary to provide a mirror image tray for use at the other side.

The tray may be made from any suitable material, such as synthetic plastics, or metal such as aliminium.

Variations may be made to the dimensions, material, and shape of the tray according to the invention, within the scope of the appended Claims, to suit different types of circuit boards and apparatus.

Claims

1. A guide tray for printed circuit boards, comprising a generally rectangular thin web, characterised in that the web has a plurality of apertures in the shape of rectangles each with one sloped end, the apertures being arranged in two rows which are symmetrical with regard to the longitudinal axis of the tray, a series of channels between the apertures constituting guide means, and a further channel forming a reinforcement for the tray.

2. A guide tray according to Claim 1, wherein the channels for guiding the board edges have a trapezoidal cross-section, in which the board edges are slid, the sloped ends of the apertures providing flared or converging mouths for the channels such that the leading corner of a board, inexactly presented, will be guided into the channel without manipulation

3. A guide tray according to Claim 1 or 2, wherein the aperture occupy most of the surface area of the tray, and serve to enable ventilation air to pass between the boards.

4. A guide tray according to Claim 1, 2 or 3, wherein the symmetrical arrangement of the tray is such that it can be used interchangeably at either side of the boards.

5. A guide tray according to any preceding Claim, wherein the latteral sides of the tray are provided with stepped or Z sectioned flanges which may be inserted into slotes in a support frame.

6. A guide frame according to Claim 5, wherein the flanges each have a plurality of protrusions which allow a reslient fit of the flane in the slot.

7. Guide tray as described herein and exemplified with reference to the drawings.