AU609212B2 - Printed circuit housing for severe environments - Google Patents

Description

OPI DATE 01/06/89 APPLN* ID 25505 88

PCT

WELTO

T AOJP DATE 06/07/89 PCT NUMBER PCT/CH88/00201 INTERNATIONALE ANMELDI..

INTERNATIONALE ZUSAMMENAKLEIT A L l t bthNS (PC1) (51) Internationale Patentklassifikation 4: INntatihi e V TV ffentkhunf mmer: WO 89/ 04559 H02B X, H02G X, H05K X Al (43) Internationales Vertiffentlichungsdatum: 18. Mai 1989 (18.05.89) (21) Internationales Aktenzeichen: PCT/CH88/00201 (81) Bestimmungsstaaten: AT (europtiisches Patent), AU, BE (europiisches Patent), CH (europaisches Patent), (22) Internationales Anmeldedatum: DE (europdisches Patent), FR (europiisches Patent), 2. November 1988 (02.11.88) GB (europaisches Patent), IT (europaisches Patent), LU (europiisches Patent), NL (europiisches Patent), SE (europdisches Patent), US.

(31) PrioritAitsaktenzeichen: 4419/87-1 (32) Priorititsdatum: 12. November 1987 (12.11.87) Verifffentlicht Mit internationalem Recherchenbericht.

(33) PrioritAtsland: CH (71) Anmelder (fir alle Bestimninungsstaaten ausser US): AS- COM HASLER AG [CH/CH]; Belpstrasse 23, CH- 3000 Bern 14 (CH).

(72) Erfinder; und Erfinder/Anmelder (nurfar US) JUZA, Augustin [CH/ CH]; Schwalmernstrasse 16, CH-3600 Thun (CH).

(74) Gemeinsamer Vertreter: ASCOM HASLER AG; Belpstrasse 23, CH-3000 Bern 14 This document contains the amendments made tnder Section 49 and is correct for printing.

(54) Title: ELECTRONIC HOUSING FOR SEVERE ENVIRONMENTAL CONDITIONS (54) Bezeichnung: ELEKTRONIKGEHAUSE FOR RAUHE UMGEB3UNGSBEDINGUNGEN (57) Abstract An electronic housing (10) comprises a tubular central piece a flat front plate (25) and a double-vaulted rear wall The central piece (11) is made of extruded aluminum and the rear wall is diecast. A printed circuit board (68) with first multiple contact strips (67) is arranged in one vault (32) of the rear wall Second multiple contact strips to which the outgoing (36) cables are connected, project from the other vault Support plates (51) for electronic components (52) are inserted in the housing (10) and are held laterally by guide grooves integrally mounted on the central piece On the front face, they make contact via their connector strips (61, 62) with the multiple contact strips (35, 67) and are retained by grooves in a stiffening rib A stirrup (75) with three bearing points for damping mechanical vibrations is screwed to each support plate The support plates (51) can be interchanged individually by means of extraction levers (69, (57) Zusammenfassung 36 68 32 67 i 62 57 61 ,,73 7 \52 I 69 S2 25 51 Das Elektronikgehiuse (10) umfasst ein rohrf6rmiges MittelstOck eine ,.ebene Frontplatte (25) und eine zweifach gew6lbte Riickwand wobei das Mittelstfick (11) aus Aluminium stranggepresst und die Rilckwand druckgegossen ist. In der einen W61bung (32) der Rflckwand (31) ist eine Verdrahtungsleiterplatte (68) mit ersten Federleisten (67) angeordnet. Durch die andere W6lbung (33) greifen von aussen her zweite Federleisten an die abgehende Kabel (36) angeschlossen sind. In das Gehiuse (10) eingeschoben sind Trilgerplatten (51) fir elektronische Baugruppen die seitlich durch am Mittelstick (11) integrierend angebrachte Fihrungsnuten gehalten sind. An der Stirnseite kontaktieren sie mit ihren Steckerleisten (61, 62) die Federleisten (35, 67) und werden durch Nuten in einer Versteifungsrippe (41) gehalten. Aufjeder Triigerplatte (51) ist zur Dumpfung von mnechanischen Schwingungen ein Biigel (75) mit drei Auflagepunkten aufgeschraubt. Jede Trigerplatte (51) kann einzeln ausgewechselt werden. Hierzu sind Auszugshebel (69, 70) hilfreich.

LI 2 The present invention relates to a housing for electronic severe components suitable for use inhes-tile environments, to such housing with connectors for the electronic components and to such housing with electronic components mounted therein.

Housings and switch boxes of various embodiments suitable for accommodating electronic circuits are known. Known in particular from patent EP 0 078 405 is a built-in plastic housing, whereby a cover and a floor portion are secured by special means to one or more annular middle sections. This 10. method permits the size of the housing to be increased or o co decreased in stages.

ooo• S. Also generally known are service elements such as S. connecting elements sockets or male plugs) which, being installed on the front and/or rear walls of such housings, enable the attachment of mating elements for the purpose of electrically connecting the housing to its environment. Such sockets and/or male plugs are connected through suitable wiring j arrangements to normally parallel-arranged circuit boards comprising the electronic components of the overall electronic *o* system.

An object of the present invention is to provide a stable too*.: and cost-effective housing for small electronic circuitry se Vcrc arrangements that is capable of operating in A/-ti-e environments while permitting an adequate transfer to the outside of heat generated by the electronic components. The proposed housing should be connected to its environment through a plurality of male plugs, sockets or female plugs.

In keeping with this object there is provided in accordance P A4/ with one aspect of the present invention, a housing suitable psspe0l6/ascom 90 7 31 Li. -L i II i i 3 for use in hes~tle- environments and serving to mechanically secure and electrically connect a plurality of plug-in type circuit boards that bear integrated electronic circuits and that are arranged parallel to one another, said housing comprising a tubular rectangular in shape rigid middle section, a front panel and a rear wall, said front panel and rear wall being detachably secured to said middle section covering respectively opposite open ends thereof; said rear wall comprising a rigid die-cast section having two domes separated one from the other by a reinforcing rib having therein a plurality of spaced apart guide notches, said guide notches Sserving to laterally or frontally secure circuit boards which can be located within said housing, one of said domes on said rear wall being adapted to accommodate a printed circuit board that bears a plurality of first plugs/sockets facing the interior of the housing; a plurality of one part of second plugs/sockets detachably secured to the housing and projecting through the other of said domes of said rear wall and into the housing, a cable of conductors extending from said second plugs/sockets; guide grooves opposite one another in the interior of the middle section for slidably receiving opposite c oo edges of respective ones of a plurality of plug-in type circuit boards that bear integrated electronic circuits and are arranged in spaced apart parallel relationship said circuit boards having another part of plugs/sockets for direct electrical contact with the corresponding first and/or second plugs/sockets upon insertion into the housing.

The invention is illustrated by way of example in the accompanying drawings wherein: 1111T4_ psspeOl6/ascom 90 7 31 Li -1 i-ir- 71 4 Figure 1 is an end view of a middle section of the proposed housing; Figure 2 is a front end view of an assembled housing of the present invention; Figure 3 is a top plan view of the assembled housing of the present invention; Figure 4 is a sectional view through the rear wall only of the housing taken essentially along the line A-A of Figure 3; and Figure 5 is a cross-sectional view of the assembled housing.

S..In Figure 1 there is illustrated a frontal end view of a middle section 11 of the housing 10 of the present invention.

The midsection 11 is an open ended tube like structure having opposite lateral walls 12, 13, a floor wall 14 and an upper side or top wall 15. The housing midsection 11 is an extruded, 0000 preferably metal, unitary section that is generally rectangular *000 S in cross-section. Arranged on the inside of each wall 12, 13, 14 and 15 of the housing are guide grooves 19, on the outer surfaces screw fastening grooves 21 and at the corner grooves 23. The grooves are defined effectively by closely adjacent eele, I ribs and thus may be considered as raised from the wall. Each of such grooves runs parallel to and along the length of the middle section 11 from one end to the other.

Figure 2 is a frontal view of a fully assembled electronics housing 10 featuring a rectangular, flat front panel 25 which, although comprising no service or display elements, is securely anchored to the front end of middle section 11 by means of a ,i/ikR, plurality e.g. ten self-tapping screws 28 that screw into the psspe0l6/ascom 90 7 31 Li. i ~z 5 grooves 21 on middle section 11. Sealing between the end of the midsection and the frontal panel 25 can be improved by the installation of a sealing component e.g. an annular sealing strip or gasket between the components and if desired located in a groove in one of the components.

Figure 3 is a plan view of the housing 10. Flat front panel 25 is fastened as described above to the front open end of the middle section 11 by screws 28 that thread into grooves 21. A rear wall 31 is likewise fastened, closing the open rear opposite end of the midsection 11, by means of self-tapping screws 28 which are threaded into grooves 21. A sealing strip Sor gasket can, as at the other end, be inserted between the o. wall and middle section 11. In place of self tapping screws S long bolts, if desired, can be used extending from one cover to the other so as to fasten both end covers 25 and 31 at the same time and clamp the midsection 11 therebetween.

lj Rear wall 31 features, on one half of its surface, a dome S 32. Detachably secured to the other half of cover 31 is a support 33, which in turn, has a plurality of multi-sockets (only the uppermost one of which is visible) detachably secured thereto. A cable 36 of conductors extends from each socket oe e Figure 4 is a section through rear wall 31 along line A-A of Figure 3. Arranged on the inside of the dome 32 are pins to which can be attached (by screws for example) a (not illustrated) circuit board. Provided on the inner face is reinforcement rib 41 which in turn has a plurality of guide notches 42. The rear wall 31 as seen from Figure 4, has eye holes 43 for receiving the fastening screws 28.

R4X Figure 5 is a cut-away plan view of the interior of housing psspe0l6/ascom 90 7 31 I i. -L -6 wherein are arranged horizontally disposed, vertically spaced apart parallel to one another, a plurality e.g. five circuit boards 51 containing electronic integrated circuits 52.

Circuit boards (printed circuit boards) 51 have their opposite edges 54, 55 fitting into guide grooves, which can be either the grooves 19 as previously described forming part of casing 11, or grooves arranged in separate guide panels 64, 65. The frontal edges 57 of circuit boards 51 are situated in the guide notches 42 of reinforcement rib 41. Arranged on frontal L0.. borders 57 are two multi-pin plugs 61, 62 of which one, 61, connects directly by its pins to multi-sockets 35 which are, as i. .o already described, detachably secured onto housing 10, while 0. the other, 62, connects to further multi-sockets 67, which are arranged on a wiring board 68. The wiring board 68 is securely fastened (with the aid of pins 40, of Figure 4) inside dome 32, and set orthogonally to circuit boards 51, and acts S essentially to interconnect circuit boards 51.

When front panel 25 is removed, circuit boards 51 can be removed individually from housing 10. For this purpose, circuit boards 51 feature two swing or pivoted arms 69, which lying against the housing walls, serve to exert outwardpulling leverage on circuit boards 51. Each female plug can, for testing or trial purposes, be individually removed or exchanged.

This arrangement, which addresses the requirements set out at the beginning, is quite compact and eliminates unnecessary wiring. Middle section 11 is designed preferably as a section of an extrusion-molded aluminium tube. Rear wall 31 and i support 33 are of die-cast aluminium. This assembly forms, .7 psspe016/ascom 90 7 31 fO V. J 7 together with the flat front panel 25, a stable, costeffective, fully metal housing that permits the effective transfer of heat from the electronic components to the outside while being suitable for employment in severe environments such as that for example inside railway locomotives where extremes of temperature, dust, oil, moisture, magnetic and electric fields make the environment generally unsuitable.

The dimension of middle section II should ideally be such e* that circuit boards 51 of the double European standard size can oooo be used in the horizontal direction while circuit boards of the standard European format can be used in the vertical direction.

S The corner grooves 23 can accommodate any desired number of

S..

screws for the purpose of screwing housing 10 to not illustrated support elements. To this end, sliding or pushing nuts can be slid into such grooves 23. The finished assembly 5.55.5 S can be attached by the front panel to e.g. a 19" frame, provided that front panel 25 is larger than the cross section of middle section 11 and possesses screw holes suitable for accommodating the 19" standard frame.

In another version, a strip 73, which is provided with notches, is screwed or otherwise secured onto front panel The notches of strip 73, together with the guide notches 42 of reinforcement 41 of rear wall 31, act to guide circuit board 51 along its from 57 and outer edges. An E-shaped strip 75 screwed onto circuit boards 51 to extend from strip 73 to reinforcement 41, acts to sharply reduce vibrations in boards 51, which can be caused, for example, by mechanical shocks to housing psspeOl9/ascom i L. I I 1_~

Claims (12)

1. 2. A housing in accordance with claim 1, wherein said middle portion, rear wall and front panel are metal.
2. 3. A housing according to claim 2 wherein said metal is aluminium.
3. 4. A housing in accordance with claim 1, wherein said plurality of said second plugs/sockets are secured to said second dome in such a way that said rlugs/sockets can, when said housing is closed, be removed individually from outside the housing.
4. 5. A housing in accordance with claim 3, wherein said plurality of one part of said second plugs/sockets are fastened by means of screws.
5. 6. A housing in accordance with claim 1, wherein said front panel includes a strip on its inside surface having grooves in which each circuit board is secured additionally on its fourth edge. o 0 7. A housing in accordance with claim 6, wherein each circuit board bears an E-shaped strip serving to reduce mechanical vibrations, and extending, on a fully-assembled circuit board, essentially between said strip on the inside surface of said front panel and said reinforcing rib.
6. 8. A housing in accordance with claim 1, wherein arranged on the outside of said middle section and, as an integral part of said middle section, are corner grooves into which nuts can be slid for the purpose of fastening said housing to support elements by means of screws.
7. 9. A housing suitable for use in severe environments psspe01l9/ascom and including plug-in type cirruit boards mounted therein, said housing serving to mechanically secure and removably receive a plurality of plug-in type circuit boards that bear integrated electronic circuits and that are arranged parallel to one another, said housing comprising an open ended tubular-shaped rigid middle section, a front panel detachably secured to said middle section and covering one open end thereof and a rear wall detachably secured to the middle section and covering the S opposite open end thereof; said middle section being an *006 extrusion-formed generally rectangular in cross-section rigid oo00 o member having grooves in the walls thereof, means anchorable in selected ones of said grooves detachably to secure said front panel and rear wall to said middle section; a plurality of plug-in type circuit boards slidably fitted into guide grooves in the interior of said housing, said rear wall comprising a ooeee S metallic die-cast section having two domes separated one from 0050 the other by a reinforcement rib having guide notches serving to receive a frontal edge of the respective circuit boards, a printed circuit board arranged on the inside of one of said 2 domes of said rear wall and having a first plurality of female sockets; a second plurality of female sockets projecting through said second dome of said rear wall, a cable extending from said second female plug to outside the housing; each said circuit board being mechanically secured along three of its edges by said guide grooves located opposite one another in said housing and a said guide notch in said rear wall, said circuit boards having plugs making electrical contact with the i<-~pp psspeOl9/ascom i 1 ,i; 11 corresponding first and/or second female sockets through one or more first and/or second male plugs arranged upon said circuit boards. An electronic assembly comprising a housing that includes a unitary tubular middle section open at opposite ends thereof and having grooves on the inner walls thereof extending from one to the other of said open ends, a flat plate like Sfront panel detachably secured to said middle section and S."0 covering one of the open ends thereof; a double-domed rear wall Qo.: detachably secured to said middle section and covering the other of the open ends thereof; a printed circuit board with o first female sockets arranged in one of said domes of said rear wall; second female sockets, to which outwardly-leading cables are attached fitting through said second dome from the outside thereof and a plurality of circuit boards slidably mounted in oooeo the grooves of opposite walls interiorly of the housing's middle section, said circuit boards further having their respective frontal edges projecting into notches in a reinforcement rib on said rear wall, said circuit boards having 2oJ male plugs at their frontal edge mating with selected ones of said sockets.
8. 11. An electronic assembly as defined in claim further including a strip having three contact points, secured to each said circuit board for the purpose of reducing mechanical vibration.
9. 12. An electronic assembly as defined in claim wherein said housing middle portion, rear wall and front panel psspe0l9/ascom R3 (-DI R A r h0, g ;r r 12 S 0 Sn. *4 45 0 5* S comprise aluminium.
10. 13. An electronic assembly as defined in claim including a strip on said front panel having grooves, in which each circuit board is secured additionally on its fourth edge.
11. 14. An electronic assembly as defined in claim including grooves on the outer surfaces of said middle section extending from one to the other of said open ends.
12. 15. A housing substantially as hereinbefore described with reference to the accompanying drawings. DATED this 17 January, 1991 SMITH SHELSTON BEADLE Fellows Institute of Patent Attorneys of Australia Patent Attorneys for the Applicant: ASCOM HASLER AG S. *SS** S psspeOl9/ascom r ;1 c-