BRIEF DESCRIPTION OF THE DRAWINGS
The seal according to the invention and its use in an electrical control unit for a hydraulic machine will be explained in greater detail in the text which follows by way of example with reference to figures, in which:
FIG. 1 shows a plan view of the seal according to the invention;
FIG. 2 shows a section through the seal according to the invention along line A-A from FIG. 1;
FIG. 3 shows a front view of an electrical control unit having a seal according to the invention;
FIG. 4 shows a section through the electrical control unit from FIG. 3 along line B-B;
FIGS. 5 and 6 each show a magnification of a detail Z from FIG. 4;
FIG. 7 shows a perspective view of a housing lower part of the electrical control unit; and
FIG. 8 shows a perspective view of a hydraulic machine having an electrical unit in which a seal according to the invention is used.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 shows a seal 1 with an edge profile 2 which surrounds a diaphragm 3. As can be seen in FIG. 2 from the section along line A-A from FIG. 1, the seal 1 has a pot-like shape. In this case, the pot base is formed by a diaphragm 3 and the edge profile 2 is formed by pot inner faces 4, pot edge faces 5 and pot outer faces 6. In order to allow contact pins 12 to pass through the seal 1, the seal 1 has openings 9 which, in other embodiments, can also be closed, and has predetermined breaking points 9 at those points at which the contact pins 12 should pass through.
As shown in FIG. 2, the pot inner faces 4 are arched towards the pot interior and are elastically deformed when a cylindrical or cuboidal plug 16, whose plug circumferential faces 16b are substantially perpendicular to the diaphragm, is inserted. On account of the elastic deformation of the pot inner faces 4 together with the first sealing faces 4a, which are arranged on the said pot inner faces, the pot outer faces 6 together with the second sealing faces 6a, which are arranged on the said pot outer faces, arch outwards. However, if the seal is used in a pot-like opening 13 in a housing 8, no arching can occur and pressure is exerted on at least one inner circumferential face 14 of the pot-like opening 13. In other words, the insertion of a plug 16 into a seal 1 without the presence of an outer surrounding receptacle increases the outer circumference of the seal 1. This can be utilized when the seal is inserted into a corresponding receptacle to provide sealing with respect to the receptacle.
For example, the seal 1 in an electrical control unit 7, as is illustrated in FIG. 3, can be inserted into a pot-like opening 13. The control unit illustrated in FIG. 3 has a housing upper part 8a and a housing lower part 8b which together form a housing 8 of the electrical control unit 7. FIG. 3 also shows, by way of example, that the pot-like openings 13 are formed in the housing lower part 8b and plug receptacles 13a are inserted into the pot-like openings 13.
A plug 16 for electrical connection to, for example, a hydraulic machine is inserted into the middle plug receptacle 13a. The arrangement of the electronic components, in particular a printed circuit board 11, is illustrated in FIG. 4 which shows a section along line B-B from FIG. 3. The printed circuit board 11 together with the electronic components located on the said printed circuit board are arranged substantially parallel to a base surface 15 of the pot-like opening 13. In this case, the contact pins 12 which are formed on the printed circuit board 11 protrude in a substantially parallel manner through housing apertures 18 and into the pot-like opening 13. In the mounted position, the seal 1 is arranged in such a way that the diaphragm 3 touches the base surface 15. At least one inner circumferential face 14 of the pot-like opening 13 is designed specifically such that the pot outer faces 6 just touch the at least one inner circumferential face 14 of the pot-like opening 13. The position of the seal 1 is fixed in the direction of the contact pins 12 by a plug receptacle 13a. FIG. 4 illustrates a plug 16 which has not yet been inserted into the plug receptacle 13a and whose outer circumferential faces 16b are substantially parallel to the inner circumferential face 14. If the plug 16 is inserted into the plug receptacle 13a such that the end faces 16a of the plug 16 elastically deform the diaphragm 3, the seal 1 or its edge profile 2 is also elastically deformed, as a result of which the first sealing faces 4a provide sealing with respect to the plug outer faces 1Gb and the second sealing faces 6b provide sealing with respect to the inner circumferential face 14.
FIG. 4 also shows that the plug receptacle 13a, in its end position, pushes the seal 1 or the edge profile 2 so far in the direction of the printed circuit board 11 that the edge profile is clamped between a seal receptacle 17 and the plug receptacle 13a.
As can further be seen from FIG. 5, the end faces of the plug receptacle 13a are perpendicular to the inner circumferential face 14, rest against the edge profile 2 and are a negative image of the abutment faces 5a and pot edge faces 5 which are formed at the seal 1. In this case, the corresponding faces of the plug receptacles 13a, like the faces of the seal which point in the direction of the seal receptacle 17, are formed in such a way that the edge profile 2 is deformed under pressure of the plug receptacle 13a in the direction of the printed circuit board 11 such that the first sealing faces 4a which are arranged on the pot inner faces 4 are arched over to a more pronounced extent in the direction of the pot interior. This increased overarching can later, when a plug 16 is inserted, increase the sealing force of the seal 1 both with respect to the plug 16 and also with respect to the pot-like opening 13 or the inner circumferential face 14.
FIG. 6 illustrates a further exemplary embodiment of the seal 1 according to the invention. In this case, the seal 1 has a material reinforcement for better sealing off of the contact pins 12 at those points at which the contact pins 12 protrude through the diaphragm.
The lower housing part 8b which is illustrated in FIG. 7 has, on its lower face, pot-like openings 13 which have housing apertures 18 in the direction of the housing inner side. A seal 10 is arranged in the housing lower part 8b in such a way that the individual regions which are provided for various groups of contact pins are separated. In this case, each contact pin group forms the mating piece for contact bushings of a plug 16 which can be inserted into the housing lower part at a later time.
The housing seal 10 serves to ensure that no encapsulation means runs into the regions between the individual contact pin groups and the printed circuit board 11 rests elastically on this housing seal 10 during encapsulation, for example of the printed circuit board 11. The edge regions of the housing seal 10 serve to ensure that no encapsulation means flows around the printed circuit board 11 (not illustrated) and comes into contact with the electronic components which are mounted on that side of the printed circuit board 11 which is opposite the contact pin groups or faces away from the housing apertures 18. FIG. 7 illustrates the housing seal 10 in a comb-like manner, with the result that encapsulation material chambers are formed for each plug region when the printed circuit board 11 is borne. The intermediate webs of the housing seal 10 are not required given suitable design of the housing or given suitable accommodation of the printed circuit board 11.
If, as illustrated in FIG. 7, a lower housing part 8b according to FIG. 4 is fitted with components, in particular with the seal 1 according to the invention, with the electronic components and with the plug receptacle 13a, without a housing upper part 8a being placed on the housing lower part 8b, and instead the electrical control unit 7 without a housing upper part, that is to say only with a housing lower part 8b, is placed onto a hollow space of a housing 20 of a drive control unit in such a way that the two elements, the hollow space and the housing lower part 8b, form a closed hollow space, a highly compact construction of a hydraulic machine is achieved, as is illustrated in FIG. 8. However, as has already been described in great detail above, the control unit 7 can also be fitted to a hydraulic machine as an individual module, that is to say with a housing upper part Ba and a housing lower part 8b.
Patent Application
20080079224
