Hydraulic controls, such as hydraulic control units or the like for transmissions, are generally known from vehicle technology. The hydraulic control device includes a housing lower side and a housing upper side, which are separated from each other by an intermediate plate. Both the housing lower side and the housing upper side feature a plural number of hydraulic supply or flow channels, which are connected through the intermediate plate by means of an allocated aperture or the like. The apertures feature a small diameter, and are therefore provided with a filter sieve to protect the apertures from contamination. Thereby, for example, flat or cylindrical filters can be installed in front of the apertures. So-called “cartridge-solutions” are also known, with which a structural unit made of an aperture and a sieve are pressed into the housing. However, such solutions cannot be installed in the intermediate plate.
It has been shown that the use of separate filter elements as aperture protection in the hydraulic control device not only involve complicated assembly, but are also cost-intensive. Furthermore, maintenance costs are high and the replacement of filters is labor-intensive.