Valve control device

2.1. Existing valve control devices are set up in housings that feature a cover and a frame in which the valve spools are embedded. Between the cover and the frame, there is the circuit carrier with the electronic components. With the new valve control device, there is no longer to be any need for a housing, and the manufacturing process is to be simplified. 2.2. In order to save the housing, the valve control device is embedded together with the circuit carrier. The compound itself provides the housing of the valve control device. In the manufacturing process, following the mechanical and electrical connection of spools and circuit carrier, the spools are positioned in the embedding tool, and the complete arrangement is then embedded preferably with epoxy resin. 2.3. Due to their high reliability such valve control devices are suitable for antilock braking systems, anti-slip control systems, electronic brake servos, and electronic stabilizing programs in motor vehicles.

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows an embedded valve control device without metal plate with the outline of a valve unit 12 . In the compound 8 , there is the circuit carrier 1 , in particular a printed circuit board populated with the electronic components 2 . The electronic components 2 may either be encapsulated in a housing or be mounted on the printed circuit board 1 as a blank chip which can also be protected by the compound 8 . At the same time spools 5 are mounted on the circuit carrier 1 via the compound. The protective cover consisting of compound features different thicknesses and solidity in different places. The spacing between two spools 5 is completely filled in with compound 8 . The remaining spool area that is the top side of the spool, its bottom and external side are only covered by a thin coating of compound 8 . The circuit carrier 1 is covered by a somewhat thicker compound layer 8 . In this figure, boundary layers between the individual embedded components are indicated. This is to suggest that the compound 8 may also consist of different materials whichmay again feature different properties. Within the spool area the compound 8 can be soft and elastic, and in the circuit carrier area it may be hard and rigid. In the area between the spools 5 and the circuit carrier 1 the compound 8 may only have low elastic properties. In order to simplify the further description of the application examples, it is assumed that the compound is homogeneous and features in all places the same properties, does not have any boundary areas, and becomes hard and rigid after processing. The spools surrounded by the compound, also designated as valve spools, consist of spool body 3 and windings 4 and represent the electric magnets by means of which the valves of valve unit 12 are operated via the valve domes 11 . The electric spool connections 7 , mounted on the side of the spool body 3 , protrude into the printed circuit board 1 . In this figure, two spools are shown that are facing each other so that their side-mounted spool connections 7 are located next to one another. This setup is particularly space-saving. The spools and the circuit carrier 1 are completely embedded, excluding the inside of the spool. In the inside of the spool, the spool body 3 is visible. The external surfaces of the spool body 3 and the spool windings 4 are positively covered by the compound 8 . This embedded arrangement protects all components, in particular the electronic components 2 , against unfavorable environmental conditions such as e.g. water, humidity, and dust. In this case, the compound 8 consists of epoxy resin. The compound 8 will become rigid when the arrangement has hardened. The embedded components such as spools 5 , circuit carrier 1 , electronic components 2 are fixed in position by the compound. With this setup, there is no longer any need for a housing. The compound 8 itself provides the housing. In the area between the spools 5 and the circuit carrier 1 , recesses are provided into which the yoke 6 can be fitted after embedding. In comparison to the electronic components 2 , yoke 6 is insensitive against any environmental influences and therefore is not embedded in this application example but subsequently fitted to the embedded arrangement. The yoke 6 , which is pushed sideways over the spool, is designed as a C-shaped yoke and features a bead 10 on its top and bottom sides. Here, within the spool body 3 , the beads 10 of the yoke 6 are positioned centrally above the cavity, into which the valve dome 11 is later introduced. Furthermore, in addition to the valve control device, this figure also shows the hydraulic assembly 12 , in particular the valve unit, whose valve domes 11 protrude into the spool body 3 . In order to produce such an embedded valve control device, it makes sense to set up the embedding tool such that it also forms domes that are introduced into the spool body and on which the spools are fixed during the embedding process. Before embedding the spool bodies 3 have been connected with the circuit carrier 1 . Here, the connection pins 7 of the spool bodies 3 do not only provide the electrical but also the mechanical connection, by means of which the circuit carrier 1 is at least partially positioned within the embedding tool. FIG. 2 shows the spool arrangement with the circuit carrier before embedding. The two spools 5 shown here each consist of a spool body 3 , on which the spool windings 4 are mounted. The connections 7 of the spools 5 have not been fitted symmetrically with regard to the spool axis but mounted on one side. The spool connections 7 are inserted through the boreholes of the circuit carrier 1 , in particular the printed circuit board, and are then fixed in position by means of pressing forces or soldering. They form a fixed unit and can be embedded together. Furthermore, there is a free space between the spools 5 and the printed circuit board 1 . The side-mounted connections and the free space are used to create mounting space for the yoke which is not shown in this figure and which is pushed sideways over the spools after embedding. The FIGS. 3 a and 3 b show the spool body. In FIG. 3 a as a side view, and in FIG. 3 b as a front view. Here, the connections 7 are fed out to one side of the spool body 3 . The connections 7 do not only have the task to provide an electrical contact between the circuit carrier and the spool but also support the printed circuit board—as shown in FIG. 2 —during the embedding process. For this reason the connections 7 must be dimensioned such that they are sufficiently stable to be able to withstand the press-fitting or soldering processes, and to support the circuit carrier. Moreover, they must be arranged such that they do not obstruct the yoke. The diameter of the cavity in the inside of the spool body must be selected to be sufficiently large so that the permissible tolerances, coming from the arrangement of the valve domes in the valve unit, can be compensated for. This takes account of the fact that the embedded spool bodies with windings will later be arranged in a fixed and immovable position in the compound. The spool body consists of synthetic material. The FIGS. 4 a and 4 b show the yoke in different perspectives. In FIG. 4 a as a side view, and in FIG. 4 b as a front view. As can be seen from the figures, the yoke 6 is designed as a C-shaped yoke and features a bead 10 on its top and bottom sides, into which the valve dome is later inserted. The yoke 6 is pushed over the spool body as shown in FIGS. 3 a and 3 b . As the yoke 6 which consists of sheet metal can only be mounted after embedding, this may also be located movably so that the interior diameter of the beads 10 does not need to compensate for all tolerances coming from the arrangement of the valve domes in the valve unit. Tolerance compensation is effected by means of the movability of yoke 3 . FIG. 5 shows an embedded valve control device with metal plate 13 and with the outline of a valve unit 12 . In the compound 8 , there is the circuit carrier 1 , in particular a printed circuit board populated with the electronic components 2 . The electronic components 2 may either be encapsulated in a housing or be mounted on the circuit carrier 1 as a blank chip. At the same time spools are mounted on the circuit carrier 1 , which feature a spool body 3 and windings 4 . Between the circuit carrier 1 and the spools, a metal plate 13 is located. The metal plate 13 features insets 14 on to which the spool body 3 is pushed. The metal plate 13 , in this embodiment, has two functions. Mainly, it is used as a component part of the yoke, and, on the other hand, it also serves as a metal body to dissipate the heat from the power components mounted on the circuit carrier 1 . The spool bodies 3 and the windings 4 , connected with the metal plate 13 —hereinafter also designated as yoke plate 13 —and the circuit carrier 1 represent the electric magnets by means of which the valves of valve unit 12 are operated via the valve domes 11 . The electric spool connections 7 , mounted on the side of the spool body 3 , protrude into the printed circuit board 1 . In this figure, two spools are shown that are facing each other so that their side-mounted spool connections 7 are located next to one another. This setup is particularly space-saving. The spools and the circuit carrier 1 are completely embedded, excluding the inside of the spool. In the inside of the spool, the interior spool body 3 is visible. The external surfaces of the spool body 3 and the spool windings 4 are positively covered by the compound 8 . This embedded arrangement protects all components, in particular the electronic components 2 , against unfavorable environmental conditions such as e.g. water, humidity, and dust. In this case, the compound 8 consists of epoxy resin. The compound 8 will become rigid when the arrangement has hardened. The embedded components such as spools, circuit carrier 1 , yoke plate 13 , and electronic components 2 are fixed in position by the compound. With this setup, there is no longer any need for a housing. The compound 8 itself provides the housing. In the area between the individual spools, recesses are provided into which the yoke bell 15 can be fitted after embedding. In comparison to the electronic components 2 , yoke bell 15 is insensitive against any environmental influences and therefore is not embedded in this application example but subsequently fitted to the embedded arrangement. The yoke bell 15 , which is pushed either from above or below over the spool, is designed as a bell-shaped yoke and features a bead 10 to one side. On the opposite side, this bead is shown by the inset 14 of the yoke plate 13 . Here, within the spool body 3 , the bead 10 and the inset 14 of the yoke plate 13 are positioned centrally on the cavity, into which the valve dome 11 is later introduced. Instead of the yoke bell 15 , which completely encapsulates the spool winding 4 , it is also possible to use a U-shaped yoke that does not cover the embedded spool winding on two sides. Furthermore, in addition to the valve control device, this figure also shows the hydraulic assembly 12 , in particular the valve unit, whose valve domes 11 protrude into the spool body 5 . In order to produce such an embedded valve control device, it makes sense to set up the embedding tool such that it also forms domes that are introduced into the valve body and on which the spools are fixed during the embedding process. Before embedding the spool bodies 5 have been connected with the circuit carrier 1 and the metal plate 13 . Here, the connection pins 7 of the spool bodies 3 do not only provide the electrical but also the mechanical connection, by means of which the circuit carrier 1 is at least partially positioned within the embedding tool. The positive connection between the valve body 3 and the inset 14 of the metal plate 13 also provides a mechanical fixing during the embedding process. FIG. 6 shows the spool arrangement with the circuit carrier and the yoke plate before embedding. The two spools 5 shown here each consist of a spool body 3 , on which the spool windings 4 are mounted. The connections 7 of the spools 5 have not been fitted symmetrically with regard to the spool axis but mounted on one side. The spool connections 7 are inserted through apertures 17 of the yoke plate 13 into the boreholes of the circuit carrier 1 , in particular the printed circuit board, and are then fixed in position by means of pressing forces or soldering. The yoke plate 13 is fixed in position by positively introducing the insets 14 of the yoke plate 13 into the spool body 3 . Spool body 3 , circuit carrier 1 , and metal plate 13 form a fixed unit and can be embedded together. Furthermore, there is a free space between the individual spools. The free space is used to create mounting space for the yoke bell which is not shown in this figure and which is pushed either from above or below over the spools after embedding. The FIGS. 7 a and 7 b show the spool body. In FIG. 7 a as a side view, and in FIG. 7 b as a front view. Here, the connections 7 are fed out to one side of the spool body 3 . The connections 7 do not only have the task to provide an electrical contact between the circuit carrier and the spool but also support the printed circuit board—as shown in FIG. 6 —during the embedding process. For this reason the connections 7 must be dimensioned such that they are sufficiently stable to be able to withstand the press-fitting or soldering processes, and to support the circuit carrier. Moreover, they must be arranged such that they do not obstruct the yoke bell. The cavity on the inside of the spool body features different diameters. The smaller diameter on the one side of the cavity in the inside of the spool body must be selected to be sufficiently large so that the permissible tolerances, coming from the arrangement of the valve domes in the valve unit, can be compensated for. This takes account of the fact that the embedded spool bodies with windings will later be arranged in a fixed and immovable position in the compound. The larger diameter on the other side, together with the sheet thickness of the yoke plate insets, must again yield the smaller diameter. The spool body consists of synthetic material. The FIGS. 8 a and 8 b show the yoke bell in different perspectives. In FIG. 8 a as a side view, and in FIG. 8 b as a front view. As can be seen from the figures, the yoke bell 15 is designed as a pot-shaped yoke and features a bead 10 on one side, into which the valve dome is later inserted. The yoke bell 15 is pushed over the spool body as shown in FIGS. 7 a and 7 b . As the yoke bell 15 which consists of sheet metal can only be mounted after embedding, this may also be located movably so that the interior diameter of the bead 10 does not need to compensate for all tolerances coming from the arrangement of the valve domes in the valve unit. Tolerance compensation is effected by means of the movability of yoke bell 3 . Instead of a yoke bell, the FIGS. 9 a and 9 b show a U-shaped yoke 16 in different perspectives. In FIG. 9 a as a side view, and in FIG. 9 b as a front view. As shown in the figures, yoke 16 is U-shaped that is, it does not completely encapsulate the spool in the same way as the bell-shaped yoke but is open on two sides. This setup also features a bead 10 on one side, into which the valve dome is later inserted. The U-shaped yoke 16 is pushed over the spool body as shown in FIGS. 7 a and 7 b . As the U-shaped yoke 16 which consists of sheet metal can only be mounted after embedding, this may also be located movably so that the interior diameter of the bead 10 does not need to compensate for all tolerances coming from the arrangement of the valve domes in the valve unit. Tolerance compensation is effected by means of the movability of the U-shaped yoke 16 . FIG. 10 a shows the yoke plate 13 from below before assembly together with the other components and before embedding. The valve spools are pushed onto the circular insets 14 . Next to the insets 14 there are apertures 17 to provide for the later feeding of the spool connections through the yoke plate to the circuit carrier. In oder to illustrate more clearly the later setup, this figure also shows the plan view of the yoke bell 15 and the U-shaped yoke 16 , which, respectively, together with the yoke plate form the yoke for a spool. FIG. 10 b shows the cross-section view through the yoke plate. The metal yoke plate 13 features insets 14 which protrude from the yoke plate level. They are later introduced into the inside of the spool. The apertures 17 in the yoke plate 13 provide for the later making of the spool connections, which represent the electrical and mechanical connection to the circuit carrier. For the embodiments shown it would seem obvious that the positively applied compound does not need to be homogeneous but may consist of different materials, and that the different materials can also be fitted in stages. In addition, the yoke components 6 , 15 , 16 , that, in the embodiments are not located underneath the compound, can also be embedded positively together with the other components, thus saving a further assembly process step.