DE9321190U1 - Component set for a housing made of plastic for receiving electrical components - Google Patents

Description

25.11.1993 TW/Be

DODUCO GMBH + Co. Dr. Eugen Dürrwächter, D-75181 Pforzheim

Component kit for a plastic housing for accommodating electrical components

Description :

The invention is based on a set of components with the features specified in the preamble of claim 1. Such a set of components is known from WO 92/20 096 and consists of a frame in which electrical conductors are embedded, which lead through the frame from the inside to the outside and in particular belong to a lead frame. The frame is supplemented to form a housing by a base plate with a raised edge and by a cover. To form the housing, the frame, the base plate and the cover are glued or welded together.

It is usual to adapt the shape and structure of the housing to the components to be accommodated and the intended use. The disadvantage of this is that you have a variety of different housings for a variety of different products. It is also known to use predefined housings for different products and, for this purpose, to adapt the carrier for the electrical components, sensors or circuits to be accommodated to the predefined housing. However, such an approach has the disadvantage of being not very flexible, since the adaptation of the component carrier is strictly limited by the need to accommodate a predetermined type and number of components.

The present invention is based on the object of creating a versatile housing.

This object is achieved by a set of components with the features specified in claim 1. Advantageous further developments of the invention are the subject of the dependent claims.

The invention does not take the approach of shaping a housing to suit the intended use and the components to be accommodated, nor does the invention take the approach of taking a standard housing and arranging the components

elements, circuits and their supports, rather the invention proposes assembling different housings from a few identical basic elements, namely a base, a frame and a cover, whereby the frame, in contrast to the prior art, is designed in a special way so that its underside and its top are profiled in a complementary manner in such a way that two identical frames with a bottom and top can be joined together without play. In its simplest embodiment, the housing therefore consists of a base, a frame and a cover as in the prior art, but unlike the prior art, the housing can be enlarged by inserting one or more frames that are identical to one another without difficulty and with minimal effort and can then accommodate further components or circuits.

When we talk about frames that are identical to one another, we mean the plastic body. The conductors, which are embedded in these during injection molding and are therefore placed in the injection mold before injection molding, can be present in different numbers and shapes depending on the application. It is advisable to use lead frames or punched grids for this purpose, in which the required conductors can be formed in the number and shape required for the application and which - with the same external dimensions of the punched grid or lead-

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frames - even with different conductor track configurations, can be easily inserted into one and the same injection mold.

The base, frame and cover can be connected to one another in a known manner, e.g. by gluing or welding, in particular by friction welding or ultrasonic welding. A seal can also be provided all around to improve the tightness of the housing.

Electrical conductors can be embedded not only in the frame, but also in the base and the lid if required, which opens up the possibility of attaching additional components to them, for example a conductor track on the base to form a ground contact, which can lead to a mounting hole on the outside of the housing through the base.

The electrical conductors leading through the frame into the housing are expediently stamped and bent parts, with which a plug can be formed as an interface on the outside of the housing by the injection molding process, in particular in such a way that an outwardly extending projection is formed on the frame, which has a blind hole in which the

Ladder ends,

If the cover is not intended to provide space for additional components, a flat plate can also be used as the cover. In an advantageous development of the invention, such a plate can serve not only as the cover of the housing, but also as a partition between two housing sections. It is particularly advantageous to provide the cover plate with a circumferential predetermined breaking point for this purpose and to form a matching, internal shoulder on the top of the frame; if you want to use the cover plate as a cover, you use it in its full size and connect it to the upper edge of the frame; if you want to use the cover plate as a partition, you break off the edge of the cover plate along the predetermined breaking point and fasten it.

the reduced plate on the lower ledge of the frame.

A particular advantage of the cover plate with a circumferential predetermined breaking point is that it allows a subsequent expansion of the range of functions of the circuit housed in the housing: For this purpose, you can simply place a cover with a complementary profile on the underside of the frame with a circuit carrier plate containing the extension onto the existing cover plate and press it in without having to remove it. If necessary, you can of course also insert one or more additional frames with additional circuit carrier plates inserted in the manner described.

If the interior of a frame is extended by a second frame or a cover designed as a hood, then the components located in the extended space can be contacted using electrical conductors that pass through the cover or the second frame. However, in order to avoid a second interface, the components located there can also be contacted using conductors.

which lead through the first frame. For this purpose, the conductor tracks are preferably bent inside so that one part of the conductors points towards the floor and another part of the conductors points towards the cover, with these two groups of conductors preferably being led through the frame in separate planes. Such an arrangement is still possible even if a plate is placed between two adjacent frames or between the frame and the cover as a partition, if there are point-shaped debit book points in this plate at the predetermined locations where the angled ends of the conductors are located, which can be penetrated by the conductors.

If the conductors only lead to the circuit board from one side, then the electrical conductors alone cannot hold the circuit board. In this case, support is required on the opposite edge, e.g. through a groove formed in the frame or through pins injected into the frame, which, like the electrical conductors, can be contacted with the circuit board using a press-fit technique.

Embodiments of the invention are illustrated in the accompanying drawings.

Figure 1 shows a construction kit made up of the basic elements of the invention.

Housing in an exploded view in longitudinal section,

Figure 2 shows a longitudinal section of a simple housing formed from it,

Figure 3 shows a comparison to the illustration in

Figure 2 Housing closed by a hood-shaped cover, 15

Figure 4 shows a housing extended by an additional frame compared to Figure 2,

Figure 5 shows a housing which, compared to the housing shown in Figure 4, is provided with a

hood-like cover is closed, and the

Figures 6 to 11 show different possibilities

the seal at the joint between two housing parts.

Figure 1 shows, as an element of the component set according to the invention, a frame made of injection-molded plastic as the basic element of the housing. This frame is open on its underside 2 and on its top 3. On its underside, a shoulder 4 is formed, from which a projection 5 projects downwards, the external dimension of which corresponds to the internal dimension d in the upper area of the frame, so that a similar frame 1 - as shown in Figure 4 - can be inserted with its extension 5 into the upper section of the other frame 1 without play. The top 3 and the bottom 4 thus have a complementary profile that enables them to be inserted together without play.

On one of the side surfaces of the frame, a projection 0 6 is formed with an outwardly open recess 7 in which the ends 8 of conductors 9 and 10 end, which form a connector strip and pass through the wall of the frame 1, in which they are embedded by injection molding. The conductors 9 and 10 are preferably made from a punched grid and are punched and bent parts that are bent at right angles, so that their

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Ends 11 and 12 point in opposite directions, namely downwards and upwards. On the wall of the frame 1 opposite the conductors 9 and 10, a projection facing the conductors 9 and 10 is formed, in which contact pins 14 are embedded, which, depending on the application, have a connection with conductors 9, 10 in the attachment 6 or not; in the latter case, they only serve as holding elements for a circuit carrier plate 15 on which electrical components 16 are located. For this purpose, the circuit carrier plate has holes 17 which are covered by spring clips 18, into which the pins 11, 12 and 14 can be pressed through the circuit carrier plate 15.

The frame 1 is closed at the bottom by a base 20, which has a projection 21 all around facing the frame 1, the inner dimension of which corresponds to the outer dimension of the projection 5 of the frame.

1. Outside the projection 21 there are fastening holes 22 with which the base plate and with it the housing can be fastened at the place of use. If desired, a plate-shaped heat sink 23 can be located in a recess in the base plate in order to absorb heat loss from components 16 and dissipate it to the outside. The heat sink 23 can be injected into the base plate 20 from the outset.

The frame 1 can be closed at the top by a cover 30 in the form of a relatively thin plate, which is expediently made of a hard plastic, but can also be made of another insulating material, e.g. ceramic. To accommodate the cover 30, a circumferential inner shoulder 19 is provided on the top 3 of the frame 1, which holds the cover 30 without play. The cover has a predetermined breaking point 31 all around, along which the edge 32 of the cover can be broken off. The width of the edge 32 corresponds to the width of the shoulder 19 (see Figure 2 ), so that the cover 30 can be pressed down over the shoulder 19 while breaking off the edge 32, whereby the edge 32 can remain on the shoulder 19. In order for the cover 30 to slide over the pins 12 and 13, it has point-shaped predetermined breaking points 33 at the corresponding locations, which can be pushed through by the pins 12 and 14. If this is done, the cover 30 takes the position shown in Figure 3.

The fourth element of the component set is a cover 40, which, in contrast to the cover 30, is not flat on the underside, but is profiled in a similar way to the underside of the frame 1 and can therefore be joined to the frame 1 from above in a form-fitting manner, whereby the

the shoulders 41 provided on the underside of the cover can serve to fix a further circuit carrier plate 15a between the cover 40 and the frame 1, preferably with the thin cover 30 interposed, which in this case fulfils the function of an intermediate wall (see Figure 3).

The basic structure of the housing shown in Figure 2 can be easily expanded by placing one or more additional frames 1 on the frame 1, whereby the cover 30 is preferably pressed down first, breaking off its edge 32. A housing expanded by a second frame is shown in Figure 4. Instead of closing the housing according to Figure 4 with a thin cover 30, it can also be closed with the profiled cover 40, as in Figure 3, and thereby create a third level, in which a third circuit carrier plate 15b can be fixed (see Figure 5).

It is an advantage of the invention that a housing as shown in Figure 2 or Figure 4 can also be subsequently expanded with additional units.

For example, the housing shown in Figure 2 can be opened by pressing in the cover plate 30 without having to remove it in order to create a cover 40 with an inserted

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Expand the circuit board 15a and then arrive at the structure shown in Figure 3. In a corresponding way, one arrives from the housing structure shown in Figure 4 to that shown in Figure 5. 5

The housing parts can be welded or glued together in a known manner (see e.g. Figure 11). However, if you want to retain the possibility of access to the inside of the housing, then the housing parts must be clamped together, e.g. by means of clamping screws running from top to bottom. In this case, a circumferential seal is expediently provided at the joints, various examples of which are shown in Figures 6 to 10: in Figure 6 an external seal, in Figure 7 an internal seal, in Figure 8 an internal O-ring seal and in Figures 9 and 10 (Figure 10 shows an enlarged detail from Figure 9) a pressed toothing, whereby the two surfaces to be pressed together are toothed and the toothings are slightly offset from one another, so that a flank pressing results.

Claims (12)

- 14 - Claims: 1. Component set for a plastic housing for accommodating electrical components, sensors and/or circuits, with a frame (1) in which electrical conductors (9, 10) are embedded, which lead from the inside to the outside through the frame (1), with a base (20) to be attached to the frame (1) on its underside (2), and with a cover (30, 40) to be attached to the frame (1) on its upper side (3), characterized in that the underside (2) and the upper side (3) of the frame (1) are profiled to complement one another in such a way that two identical frames (1) with underside (2) and upper side (3) can be joined together without any play. 2. Component set according to claim 1, characterized in that it contains a seal (Fig. 6-8) and that the bottom (2) and top (3) of the frame (1) are profiled so that between two adjacent There is a gap all around the assembled frame (1) to accommodate the seal (Fig. 6-8). 3. Component set according to claim 1 or 2, characterized in that electrical conductors are embedded in the base (20) and lead through the base (20) from the inside to the outside. 4. Component set according to one of the preceding claims, characterized in that electrical conductors are embedded in the cover (40) and lead through the cover from the inside to the outside. 5. Component set according to one of the preceding claims, characterized in that the conductors (9, 10) are stamped and bent parts. 6.. Component set according to one of the preceding claims, characterized in that the ends (8) of the conductors (9, 10) projecting outward from the frame (1) are located in a housing extension (6) to form a plug. 7. Component set according to one of the preceding claims, characterized in that the conductors (9, 10) have angled sections (11, 12, 14) in the interior of the frame (1) transverse to the frame plane. - 16 - 8. Component set according to claim 7, characterized in that two rows of conductors (9, 10) traverse the frame (1) in mutually parallel planes and are angled in opposite directions in the interior. 9. Component set according to claim 7 or 8, characterized in that the cover (30) is flat and point-shaped predetermined breaking points (33) for forming openings for the passage of the angled ends (12, 14) of the conductors. 10. Component set according to one of the preceding claims, characterized in that the cover (30) has a circumferential predetermined breaking point (31) and the frame (1) has a matching inner shoulder (19) on its upper side (3). 11. Component set according to one of claims 1 to 8, characterized in that the cover (40) has on its underside a profile matching the upper side of the frame (1). 12. Component set according to claim 11, characterized in that the cover (40) has space for receiving a circuit carrier plate (15a).