GB2047481A

GB2047481A - Terminal strip for a circuit board and housing for receiving same

Info

Publication number: GB2047481A
Application number: GB8008400A
Authority: GB
Original assignee: Luetze Elektro Friedrich GmbH; LUETZE FRIEDRICH ELEKTRO
Current assignee: Luetze Elektro Friedrich GmbH; LUETZE FRIEDRICH ELEKTRO
Priority date: 1979-03-17
Filing date: 1980-03-12
Publication date: 1980-11-26
Also published as: IT8020632A1; DE2910619C2; IT1149911B; GB2047481B; FR2452184A1; IT8020632A0; DE2910619A1; FR2452184B1; CH653511A5

Abstract

A terminal strip (1) for a printed circuit board (6) comprises an insulating body (2) moulded around a set of coplanarly disposed terminals (3). Each terminal has an L-shaped connecting wire (8, 9) extending therefrom in that plane (5) to project from a flat side wall (11) of the body (2). The side wall (11) is perpendicular to the plane (5) and abuts the circuit board (6) to which the projecting ends (10) of the connecting wires (8, 9) are soldered. Each terminal (3) has an aperture (13) therethrough for receiving a connecting lead (14) from either side, and a U-shaped plate (15-17) retained on the lead-retaining screw (4) projects into the aperture (13) to protect the lead (14) from wear by the screw (4). An injection moulded synthetic material housing (21, 22) is provided in which at least one terminal strip (1) is mounted. The housing base (21) and cover (22) comprise mutually perpendicular walls (23-27), from plate (30) and internal webs (33, 34, 41, 42) providing location for the terminal strips (1) and/or dummy aperture covers (40). The terminal strips (1) are inserted in the housing (21, 22) through apertures (36-39) through which the lead retaining screws (4) are accessible. <IMAGE>

Description

SPECIFICATION Terminal strip for a circuit board and housing for receiving same The invention relates to a terminal strip for a board supporting a printed circuit, which terminal strip, in a common insulating housing, contains a plurality of metal terminals located side-by-side in a row, each with one of several terminal screws, whereof the axes are located in a common plane and each with a connecting wire extending at least approximately parallel to this plane, for the individual terminals, which wire projects by its free soldered end from the insulating member and to a housing for receiving the circuit board and the terminal strip.

Housings for receiving mounting boards supporting printed circuits are already known, in which terminals are arranged in a cover part which can be fitted on a lower part of the housing, which cover part must be connected to the mounting board subsequently. In these known embodiments, it is seen as an essential drawback that the mounting board constructed as a printed circuit board and the electronic parts to be attached to the latter have to be fitted individually in the housing, in which case the connection of these parts to each other and to the terminal strip must be carried out by means of wires to be fitted individually or of a second printed circuit board, which is at right angles to the aforementioned printed circuit board and must be connected to the latter by soldering.If two such circuit boards arranged at right angles to each other are used, then the latter are connected to each other solely to be electrically conducting, but less mechanically stable. In order to achieve adequate stability for the two circuit boards arranged at an angle with respect to each other, special mechanical stabilising devices must be provided, which make installation in the housing and mutual connection of the individual electrical or electronic components substantially more expensive.

The object of the invention is to provide a simple and inexpensive construction of a terminal strip and housing which is designed constructionally for this terminal strip, which makes it possible to solder a flat printed circuit board already connected to its electronic components and the terminal strip, as a whole, mechanically, in a single operation, and then to insert the latter in the housing as a complete finished intermediate product, without any subsequent work.A secondary objective is that the housing should be designed so that it can be easily constructed with different housing depths according to the number of electronic components used and adapted to the number of necessary terminals and that in addition, with high stability, the housing is able to withstand all mechanical stresses occuring at the time of assembly, such as, for example, torsional forces at the time of tightening the terminal screws as well as compressive and lateral forces.

The invention provides a terminal strip for a board provided with a printed circuit, which strip comprises an insulating member containing a plurality of metal terminals arranged in side-by-side disposition whereof their axes lie in a common plane, each terminal having a respective terminal screw and each having a connecting wire extending therefrom in a direction substantially parallel to this plane, which wire projects from the insulating member, characterised in that within the insulating member each connecting wire comprises two sections disposed substantially at right angles to each other.The necessary stability of the housing and the simplified installation of the terminal strips constructed according to the invention may be achieved by having the bent sections of the connecting wires emerging on a narrow side of the insulating member, which side extends at right angles to the common plane, and projecting by their soldered ends at this point.

Particularly advantageous details of the invention will become apparent from the features described hereinafter in conjunction with the embodiments of a terminal strip according to the invention and of matching housings serving to receive the latter. These embodiments are illustrated in the drawings in which:: Figure 1 shows a terminal strip in longitudinal section; Figure 2 is an end elevational view of the strip of Fig. 1; Figure 3 shows the terminal strip in crosssection on line Ill-Ill of Fig. 1 and installed in a a housing shown in a cutaway view; Figure 4 shows the housing with three terminal strips according to Figs. 1 to 3 inserted in a longitudinal section on line IV-IV of Fig. 5; Figure 5 shows the housing in plan view looking towards its front plate; Figure 6 is a cross-section on line VI-VI of Fig. 4; Figure 7 is an elevational view from the side, with the cover part removed from the base part of the housing and the circuit board with terminal strips attached thereto partly removed from the base part; Figure 8 shows another housing, the depth of which is increased to receive a 5-pole terminal according to the invention;; Figure 9 shows the right hand half of the cover part on a greatly increased scale; and Figure 10 is a vertical section on the broken line X-X of Fig. 9.

The terminal strip 1 according to the invention illustrated on an enlarged scale in Figs. 1 to 3 comprises an insulating member 2 moulded from thermosetting synthetic material, in which a plurality of metal terminals 3, arranged side-by-side in a row, are embedded so that the axes of rotation of their terminal screws 4 lie in a common plane designated by the reference numeral 5 in Figs. 2 and 3.

The terminal strip 1 is intended for attachment to a board supporting a printed circuit (not shown), designated by the reference numeral 6 in Figs. 1 and 6, on which board the terminal strip can be mounted so that the aforementioned common plane 5 of the axes of the terminal screws 4 projects at right angles from the upper side 7 of the board. For this, the connecting wires 8 connected to the terminals 3 are bent at right angles in the manner shown in Fig. 1 and are embedded in the insulating member so that their bent end sections project by their soldered ends 10 beyond the long narrow end face 11 of the insulating housing 2, in which case they have a mutual spacing which corresponds to the grid size selected for the printed circuit provided on the board 6.

The terminals 3 respectively have a continuous insertion opening 13, which is accessible from both sides, for a connecting wire 14, as illustrated in Fig. 3. In order that the thin wires cannot be damaged when the terminal screws 4 are tightened, a wire-protecting plate 15 bent in the form of a yoke is provided, which penetrates the insertion opening 13 with its lower side 16 and penetrating the side 17 of which, extending outside the terminal 3, is the associated terminal screw 4.

As shown clearly in Fig. 2, the insulating member 2 of the terminal strip is constructed to be symmetrical with respect to the common plane 5 containing the connecting wires 8 and their bent end sections 9. In detail, at its upper part containing the terminals 3, the insulating member is wider than at its lower part 18 containing the connecting wires, which lower part 18 is defined with respect to the upper part by lateral shoulders 19. This provides a favourable support for the terminal strip when the terminal screws 4 are tightened, whereby this tightening torque is simultaneously introduced to the subsequently described housing serving to receive the aforementioned terminal screws.There is thus no load on the soldered ends 10 soldered to the conducting paths provided at this point, which ends project from the rear side of the board 6, whereby simultaneously, the insulating member is constructed to be flat on the end face 11 containing the soldered ends 10 and the end face 11 extends at right agles to the longitudinal direction of the insulating member. In this way, possible twisting moments produced when the terminal screws are tightened can be transmitted to the board 6 over a large surface area, without any fear of damage to the board.

The housing constructed according to the invention and illustrated in detail in Figs. 3 to 10 can receive up to four of the above described terminal strips 1 and is injection moulded for example from a thermoplastic or thermosetting synthetic material. In detail, it consists of a deeper base part 21 and shallower cover part 22. Both parts have corresponding and registering main walls 23, 24, which extend parallel to each other in the closed state illustrated in Figs. 5 and 6 and when secured with respect to each other bring about attachment of the board 6 supporting the plug strip or strips.

The base part 21 of the housing comprises enclosing walls connected in one piece to the main wall 23 and projecting at right angles from the latter, namely two side walls 25 and 26 which are parallel to each other and a bottom wall 27 disposed at right angles to these side walls. The cover part 22 illustrated on an enlarged scale in Figs. 9 and 10 can be fixed with respect to the free end faces of these enclosing walls, as will be described hereafter in detail. As shown in Fig. 4, two claw-like projections 28 and 29 are provided on the bottom wall 27, which projections are concealed by the associated main wall 23 of the base part, but from the other side facilitate the fitting of the housing on a quickattachment base.

In the preferred position of use of the housing, as shown in Fig. 7, the two main walls 23 and 24 are vertical. In this position, the housing can be closed off on its upper side by a front plate 30, on which not only markings or indications or attachment members such as flat plugs or operating members, for example potentiometer spindles can be located, but also connecting means for the attachment of a second housing of the type constructed according to the invention. In the embodiment illustrated, the front plate 30 is inserted in two lateral guide grooves 31 and 32.The latter are provided on the facing inner sides of two web-like walls 33 and 34, which extend at right angles to the lower bottom wall 27 from the upper edge 35 of the main wall 23 parallel to the side walls 25 and 26 and opposite these side walls provide four apertures 36, 37 and 38 and 39 in all, whereof in the arrangement illustrated in Fig.

4, only the apertures 37 to 39 are occupied respectively by a terminal strip 1, whereas the right-hand upper aperture 36 is closed by a dummy strip 40. Provided between the aforementioned two web-like walls 33 and 34, which are flush with the main wall 23 at the upper edge 35, and the two side walls 25 are two further web-like walls 41 and 42, which are provided at their upper and lower end respectively with an enlarged extension 43, 44, which contain an insertion groove 45 for a dummy strip 40 of the aforementioned type.

In a corresponding manner, enlarged extensions 46 are provided at the lower end of the web-like walls 33 and 34, which extensions respectively contain an insertion groove 47 for a dummy strip 40 as well as a bore 48, in which a tightening screw (not shown in the drawing) for attaching the cover 22 to the base part 21 can be screwed.

An enlarged extension at the upper end of the two side walls 25 and 26 is located opposite the enlarged extensions 44 located at the lower end of the web-like walls 41 and 42, which extensions 44 also comprise a bore 49 for receiving a securing screw (not shown) for the cover.

In the arrangement illustrated in Fig. 4, a terminal strip of the above described type constructed according to the invention is inserted between the two enlarged extensions 43 and 46 on the two web-like walls 41, 33 and between the extensions 44 and 50. The extensions 44, 50 and respectively 43, 46 are located with slight clearance opposite the lower parts 18 of the terminal strips 1 directed towards the bottom wall 27 and therefore in the manner aforedescribed are able to withstand in a simple manner the torque exerted when wires are secured.

As shown clearly by Fig. 4, the two intermediate walls 41 and 42 are staggered with respect to the web-like walls 33, 34 and the side walls 25, 26 so that they cover the internal insertion openings 13 of the terminals 3 with respect to the interior of the base part 21. The connecting leads of the type illustrated at 14 in Fig. 3 and introduced into the terminals 3 are thus prevented from coming into contact with each other or from causing short-circuiting.

The cover part 22 illustrated in Figs. 9 and 10 has peripheral enclosing walls 51, which may meet the end faces of the side walls 25 and 26 and bottom wall 27 at an obtuse angle. In this case, they surround the board 6 at their edges. The necessary clamping pressure for retaining the board is provided by four extensions 52 in the form of eyelets on the inner side of the cover part 52. These extensions respectively contain a bore 53 for receiving securing screws (not shown), which can be screwed into the bores 48, 49 in the web-like walls 33, 34 and into the extensions 44 of the intermediate walls 41 and 42.

In order to prevent lateral displacement of the cover part, the two side walls 25 and 26 are provided with two edge strips 54 projecting beyond their end faces, which strips engage in matching recesses 55 when the cover part 22 is fitted. Furthermore, each of the web-like walls 33 and 34 is provided with a raised extension 56, which engages in a recess 57 on the upper edge of the cover.

Finally, located below the extensions 43 at the upper end of the intermediate walls 41 and 42 is a cylindrical peg 58, which engages in a sleeve-like extension 59 on the inner side of the cover part, when the cover part 22 is fitted.

The modified embodiment according to Fig.

8 shows that whilst using the same cover 22, the depth of the base part 61 can be increased so that even terminal strips with five or more poles can be used. Fig. 8 shows 5pole terminal strips of this type designated by the reference numeral 62. For 5-pole terminal strips of this type, the lower part of the insulating member 2 of the terminal strip, as indicated by broken lines in Fig. 3, can be provided with an extension 63, in which the connecting leads 64 and 65 necessary for the two additional terminals can be located.

The particular advantage of the invention consists in that a simple and economical construction of a terminal strip and of a housing intended for this terminal strip is provided, which provides the possibility that before its mounting, a flat board can be equipped with the electronic components provided and can be provided with the terminal strip and that the board so equipped can be soldered as a whole, mechanically, in a single operation, and then fitted as a complete finished unit without any subsequent work in the housing constructed according to the invention. Furthermore, the housing is constructed so that all mechanical forces occuring at the time of mounting, in particular screwing forces produced when tightening the terminal screws, as well as compressive and lateral forces, can be absorbed by the housing, with high stability. A further advantage consists in that the depth of the housing can be changed without substantial modifications to the injection moulds provided for its use, if necessary it can be adapted to the greater height of components provided on the board.

As a result of their symmetrical construction, the wire-protecting pates 15, 16 of the terminal strip can be inserted in the terminal from both sides so that one and the same terminal is suitable for left-handed or righthanded installation in the housing.

Claims

1. A terminal strip for a board provided with a printed circuit, which strip comprises an insulating member containing a plurality of metal terminals arranged in side-by-side disposition whereof their axes lie in a common plane, each terminal having a respective terminal screw, and each having a connecting wire extending therefrom in a direction substantially parallel to this plane, which wire projects from the insulating member, characterised in that within the insulating member, each connecting wire comprises two sections disposed substantially at right angles to each other.

2. A terminal strip according to claim 1, characterised in that one of the sections of each connecting wire emerges on a side of the insulating member, which extends at right angles to the common plane, and projects therefrom by a free end at this point.

3. A terminal strip according to claim 2, characterised in that both of the sections of each connecting wire are located in the common plane.

4. A terminal strip according to claim 1 or claim 3, characterised in that the free ends are separated from each other by intervals adapted to the grid size of the board to which said terminal is to be attached.

5. A terminal strip according to any one of claims 1 to 4, characterised in that the insulating member is of a synthetic material and is injection moulded around the terminals together with their connecting wires.

6. A terminal strip according to any one of claims 1 to 5, characterised in that each of said terminals has an insertion opening there-through for a connecting lead, which opening is accessible from both sides of said terminal.

7. A terminal strip according to claim 6, characterised in that projecting into the insertion opening is a lead-projecting plate, the end section of which can be held against an inserted connecting lead by the terminal screw of the terminal.

8. A terminal strip according to claim 7, characterised in that the lead-projecting plate is bent in a U-shape and that the terminal screw passes through said plate on a side thereof located outside the insertion opening.

9. A terminal strip according to any one of claims 1 to 8 characterised in that the insulating member is constructed to be symmetrical with respect to the common plane.

10. A terminal strip according to claim 9, characterised in that at an upper part containing the terminals the insulating member has a greater width than at a lower part thereof containing the connecting wires, which lower part is defined with respect to the upper part by lateral extending shoulders.

11. A terminal strip according to claim 10, characterised in that the end face of the insulating member from which project the soldered ends, is constructed to be flat, and substantially at right angles to the longitudinal direction of the insulating member.

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12. A housing containing at least one terminal strip according to any one of claims 1 to 11, characterised in that the housing is moulded from synthetic material, and consists of a base part and a cover part which is shallow relative to said base part.

13. A housing according to claim 12, characterised in that the base part and cover part have corresponding registering main walls which walls extend parallel to each other when the housing is closed and in use are retained in said position, and comprise means for the attachment of a board supporting the terminal strip.

14. A housing according to claims 12 or 13, characterised in that at least the base part of the housing has mutually perpendicular enclosing walls connected to its main wall against free end faces of which walls the cover part in use is fixed.

15. A housing according to claim 14, characterised in that the enclosing walls of the base part comprise two parallel side walls and a bottom wall located at right angles to the latter, and a front plate located opposite to and spaced from the bottom wall.

16. A housing according to claim 15, characterised in that located between the front plate and at least one of the side walls is an aperture in which is received said terminal strip, through which aperture the terminals and terminal screws of the terminal strip inserted therein are accessible.

17. A housing according to claim 16 characterised in that an aperture is respectively located between the front plate and each of the two side walls.

18. A housing according to claim 17, characterised in that projecting from the main wall of the base part are two web-like walls each defining one of the apertures which walls extend parallel to the side walls.

19. A housing according to claim 18, characterised in that the two web-like walls are connected to said front plate.

20. A housing according to claim 19 characterised in that at their ends remote from the upper edge of the main wall the web-like walls have extensions projecting towards the adjacent side wall.

21. A housing according to claim 20, characterised in that the extensions each have guides adapted to receive a dummy cover for the aperture when no terminal strip is inserted in any one of said apertures.

22. A housing according to any one of claims 18 to 21, characterised in that located substantially centrally between each of the web-like walls and its adjacent side wall is an intermediate wall which extends parallel to the side wall.

23. A housing according to claim 22, characterised in that relative to a web-like wall the respective intermediate wall is offset in its longitudinal direction at least by an amount equal to the height of the upper part of the terminal strip in the direction of the bottom wall.

24. A housing according to claim 22 or 23, characterised in that at at least one end of each intermediate wall there is a projecting extension which extension is adapted to guide the lower part of the terminal strip.

25. A housing according to claim 24, characterised in that provided in each of the extensions is a guide groove adapted to receive a dummy cover, which groove extends at right angles to the longitudinal direction of the intermediate wall and at right angles to the main wall of the base part.

26. A housing according to any one of claims 22 to 25, characterised in that the web-like walls and/or the intermediate walls contain recesses adapted to receive screws serving for the attachment of the cover part.

27. A housing according to any one of claims 22 to 26, characterised in that provided on the intermediate walls are pegs which fit in matched counter-recesses provided in the cover part and in the terminal board.

28. A housing according to any one of claims 22 to 27, characterised in that the web-like walls and/or the intermediate walls serve as a rear wall for the terminals and prevent penetration thereof by a connecting wire.

29. A housing according to any one of claims 22 to 28, characterised in that the web-like walls and/or the intermediate walls provide location of the terminal strip or strips.

30. A housing according to any one of claims 18 to 29, characterised in that provided on the end faces of the side walls are projecting strips adapted to engage in matching recesses on the side walls of the cover part.

31. A housing according to any one of claims 18 to 30, characterised in that located on the outer side of the bottom wall of the base part are guides, adapted to slidably receive a base.

32. A terminal strip according to claim 7, characterised in that each terminal is adapted to receive the lead-projecting plate from either of opposed sides thereof for left-handed or right-handed mounting of said terminal in a housing.

33. A terminal strip substantially as hereinbefore described with reference to and as illustrated in Figs. 1 to 8 of the accompanying drawings.

34. A housing, containing at least one terminal strip, substantially as hereinbefore described with reference to and as illustrated in Figs. 3 to 10 of the accompanying drawings.