Abstract:
A valve arrangement includes an operating valve arrangement in the form of a relay valve and a control valve arrangement. The control valve arrangement includes a controlled inlet valve and a controlled outlet valve. Solenoid valves are provided for selectively routing pressure medium. A first control piston and a second control piston, which can be subjected to pressure by a pressure medium via operation of the solenoid valves, control actuation of the inlet valve and the outlet valve of the control valve arrangement. The control valve arrangement is installed directly on the housing of the operating valve arrangement to achieve a compact structural unit and to reduce the amount of pressure medium channels and pressure medium connections required. The operating valve arrangement and the control valve arrangement are designed such that parts of the control valve arrangement are located in, or constituted by, the operating valve arrangement. The pressure medium outlet of the control valve arrangement is connected to the pressure medium outlet of the operating valve arrangement, thereby permitting use of a single noise suppressor for the valve arrangement to suppress the exhaust noise.

Description:
BACKGROUND OF THE INVENTION 
     The present invention relates to a valve arrangement of the type including an operating valve arrangement provided in the form of a relay valve and a control valve arrangement, used, for example, for regulating supply of a pressure medium in a vehicle braking system equipped with an anti-lock braking (ABS) system. 
     A valve arrangement of this type, which consists generally of a relay valve and a control valve arrangement, is known, for example, from the valve design embodied as instrument number 472 500 100 0 of the company WABCO GmbH. Such valve arrangement can be used with a vehicle braking system equipped with an anti-lock braking (ABS) system. Insofar as the control valve arrangement is actuated by the ABS electronic system, use of this valve arrangement permits the brake cylinders of the vehicle brake system to be aerated or vented independently of the pressure controlled by the motor vehicle brake valve. When in a passive state, the valve arrangement functions as a relay valve used for rapid aeration and venting of the brake cylinders. 
     In the aforementioned valve arrangements, it is advantageous for the relay valve and the control valve arrangement to be mounted as close together as possible in order to keep the paths of the pressure medium as short as possible. This has been accomplished, for example, by attaching the relay valve and the control valve arrangement on a common support, or connecting them to each other by means of bridging elements. The pressure medium connections between the relay valve and the control valve arrangement are then established by means of pressure medium lines that are advantageously as short as possible. 
     It is the object of the present invention to provide a valve arrangement of the type mentioned above in which placement of the valves of the valve arrangement relative to each other and the nature of pressure medium connections of the valve arrangement can be improved. 
     SUMMARY OF THE INVENTION 
     In accordance with these and other objects of the invention, there is provided a valve arrangement which includes an operating valve and a control valve arrangement. The operating valve includes a housing defining a pressure medium input chamber, a pressure medium output chamber and a pressure medium outlet leading to a pressure medium sink. The operating valve also includes an inlet and outlet valve arrangement via which the pressure medium output chamber may be selectively connected to the pressure medium input chamber or to the pressure medium outlet, or can be closed off from both. The control valve arrangement is installed directly on the housing or in a recess formed in the housing of the operating valve arrangement, and includes a pressure medium input chamber, a pressure medium output chamber and a pressure medium outlet. The control valve arrangement further includes a controlled valve arrangement via which the pressure medium output chamber can be selectively connected to the pressure medium input chamber or to the pressure medium outlet of the control valve arrangement. The pressure medium outlet of the control valve arrangement is connected to the pressure medium outlet of the operating valve arrangement. The operating valve arrangement and the control valve arrangement are advantageously designed and connected to each other in such manner that at least a portion of the control valve arrangement is located in, or constituted by, the operating valve arrangement. 
     The invention offers, in particular, the advantage of maintaining a valve arrangement comprising an operating valve arrangement and a control valve arrangement combined into one compact component of simple structure. 
     By combining the operating valve arrangement and the control valve arrangement into one compact component, the paths of the pressure medium are shortened, such that a better response behavior of the valve arrangement is achieved. In addition, such design obviates the use of bridging elements and reduces the expense otherwise required for external pressure medium lines and screw connections. 
     By connecting the pressure medium outlet of the control valve arrangement to the pressure medium outlet of the operating valve arrangement, only one noise suppressor is required for proper function. 
     According to a further embodiment of the invention, part of the control valve arrangement is located in, or constituted by part of, the operating valve arrangement. 
     According to advantageous further developments of the invention, a valve seat or a receptacle for the valve seat of a solenoid valve of the control valve arrangement is installed in or at the operating valve arrangement, or is formed by part of the operating valve arrangement. The seat of the a control piston of the control valve arrangement is formed by facing sides of an area portion of the operating valve arrangement and an area portion of the control valve arrangement. 
     By virtue of the above-mentioned measures, the invention provides the advantage that the controllable valve arrangement of the control valve arrangement and the solenoid valves can be assembled and disassembled easily. Due to the fact that the above-mentioned valves and the control piston are located in areas of the operating valve arrangement and of the control valve arrangement which border each other, repair work or the replacement of components merely requires that the housing of the control valve arrangement be removed from the housing of the operating valve arrangement. 
     In accordance with an advantageous embodiment of the invention, the control valve arrangement is located laterally on the upper part of the housing of the operating valve arrangement. This arrangement has the advantage that the electrical system which serves to process electrical signals and to actuate the valve arrangement electrically can also be mounted on the valve arrangement. 
     The above, and other objects, features and advantages of the present invention will become apparent from the following description read in conjunction with the accompanying drawings, in which like reference numerals designate the same elements. 
    
    
     BRIEF DESCRIPTION OF THE FIGURES 
     FIG. 1 is a cross-sectional view of a valve arrangement consisting of an operating valve arrangement and a control valve arrangement in accordance with an embodiment of the invention in which the control valve arrangement is located laterally of the operating valve arrangement on the lower part of the housing; and 
     FIG. 2 is a cross-sectional view of a valve arrangement in accordance with another embodiment of the invention substantially identical to the valve arrangement shown in FIG. 1, in which the control valve arrangement is provided in the form of a lid located laterally of the operating valve arrangement on the upper part of the housing. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring now to the figures, and in particular FIG. 1, a valve arrangement in accordance with an embodiment of the invention includes an operating valve arrangement  66  and a control valve arrangement  65  combined into one component. 
     The operating valve arrangement  66  is provided in the form of a relay valve in which a piston serving as a relay piston  2  is movably installed in a housing  4 ,  1  comprised of a lower housing part  4  and an upper housing part  1 . One side of the relay piston  2  forms the boundary of a control chamber  6 , and the other side thereof, located away from the control chamber  6 , similarly delimits a pressure medium output chamber  10 . 
     The pressure medium output chamber  10  can be selectively connected via an inlet and outlet valve arrangement  13 ,  12 ,  11  to a pressure medium input chamber  16  or a pressure medium outlet  20  of the housing  4 ,  1 , or can be closed off from both. The inlet valve  13 ,  12  of the inlet and outlet valve arrangement  13 ,  12 ,  11  is comprised of a ring-shaped inlet seat  13  and a valve closing element  12  which is movable relative thereto. The valve closing element  12  is biased against the inlet seat  13 , by a spring  18 . The outlet valve  11 ,  12  is formed by the free end of a tubular extension of the relay piston  2  configured as an output seat  11 , and the valve closing element  12 . The end of the pressure medium outlet  20  lets out into a chamber  8  in which noise-suppressing means  22  are provided. The wall surrounding the above-mentioned chamber  8  is provided with passage openings  23  for the pressure medium. The chamber  8 , and the noise-suppressing means  22 , which may be made of a knit plastic material, constitute components of a noise suppressor which is preferably connected in a removable manner to the housing  4 ,  1 . 
     The control chamber  6  is connected to a control input  7  of the housing  4 ,  1 , which, in turn, can be selectively connected to a source of control pressure or to a pressure medium sink via a valve (not shown), in the form of, for example, a motor vehicle braking valve. The pressure medium input chamber  16  is connected to a pressure medium input  15  of the housing  4 ,  1 , which, in turn, is connected to a source of pressure medium. A pressure medium output  9  of the housing  4 ,  1  is connected to the pressure medium output chamber  10 . 
     The control valve arrangement  65  includes a housing  63  which is laterally attached to the lower housing part  4  of the operating valve arrangement  66  by means of suitable fasteners, for example, screws. The housing  63  of the control valve arrangement  5  is provided with a pressure medium input chamber  59 , a pressure medium output chamber  57  and a pressure medium outlet  21 . The pressure medium input chamber  59  is connected to a pressure medium input  64  of the housing  63 . The control valve arrangement  65  and the operating valve arrangement  66  are positioned relative to one another in such a manner that the pressure medium input  64  of the control valve arrangement  65  is directly aligned with the pressure medium output  9  of the operating valve arrangement  66 . The pressure medium output chamber  57  is connected to a pressure medium output  55  of the housing  63 . A consumer (not shown), provided, for example, in the form of a brake cylinder, is connected to the pressure medium output  55  via a suitable pressure medium channel. 
     The pressure medium input chamber  59  and the pressure medium output chamber  57  of the control valve arrangement  65  can be selectively connected to each other or closed off from one another via a first controlled valve serving as an inlet valve  58 ,  56 . A first control piston  53  is provided to permit actuation of the inlet valve  58 ,  56 . The first control piston  53  is formed by a membrane, an outer edge of which is disposed between facing sides presented by an area portion  61  of the operating valve arrangement  66  and an area portion  60  of the control valve arrangement  65 , and is held in place, for example, by clamped engagement between these two area portions  61  and  60 . The area portions  51  and  60  thus serve as seats for the first control piston  53 . The inlet valve  58 ,  56  is comprised of an inlet seat  58  which is integral to the housing and a valve closing element  56  which is formed by a reinforced area of the membrane. The valve closing element  56  is biased against the inlet seat  58  by a spring  54 . One end of the spring  54  is supported by the housing  4 ,  1  of the operating valve arrangement  66 , and an opposite end thereof biases the valve closing element  56  in the direction of the inlet seat  58 . 
     The pressure medium output chamber  57  of the control valve arrangement  65  can be selectively connected to or closed off from the pressure medium outlet  21  of the control valve arrangement  65  via a second controlled valve serving as an outlet valve  52 ,  51 . The pressure medium outlet  21  of the control valve arrangement  65  lets out into a pressure medium channel  19  provided in the form of a housing channel located in the housing  4 ,  1  of the operating valve arrangement  66 . The end of the pressure medium channel  19  distant from the pressure medium outlet  21  of the control valve arrangement  65  in turn lets out into the pressure medium outlet  20  of the operating valve arrangement  66 . Thus, the pressure medium outlet  21  of the control valve arrangement  65  is connected directly to the pressure medium outlet  20  of the operating valve arrangement  66 , rather than being connected to the pressure medium outlet  20  via the pressure medium output chamber  10  of the operating valve arrangement  66 . By virtue of such design, a common pressure medium outlet provided in the valve arrangement  66 ,  65  is alone sufficient to permit a venting of the consumer in a manner independent of a venting of the pressure medium output chamber  10  of the operating valve arrangement  66 . 
     The inlet valve  58 ,  56  and the outlet valve  52 ,  51  together form a controlled valve arrangement  58 ,  56 ,  52 ,  51  by means of which the pressure medium output chamber  57  of the control valve arrangement  65  can be selectively connected, as mentioned above, to the pressure medium input chamber  59  or to the pressure medium outlet  21  of the control valve arrangement  65 . 
     A second control piston  49  permits actuation of the outlet valve  52 ,  51 . The second control piston  49  is also formed by a membrane, an outer edge of which is attached in a seat of the control piston  49  located in the housing  63  of the control valve arrangement  65 . The outlet valve  52 ,  51  comprises an outlet seat  52  integral with the housing  63 , and a closing element  51  which is formed by a reinforced area of the membrane. The closing element  51  is held in biased contact against the outlet seat  52  by a spring  50 . 
     One side of the first control piston  53  delimits the pressure medium input chamber  59  located in the housing  63  of the control valve arrangement  65 , and the other side of the first control piston bounds a first control chamber  62 , located within the housing  4 ,  1  of the operating valve arrangement  66  or constituted by a recess in the wall of the housing  4 ,  1  of the operating valve arrangement  66 . As depicted, the recess constituting the first control chamber  62  is located in the side of the wall of the housing  4 ,  1  adjoining the control valve arrangement  65 . One side of the second control piston  49  delimits the pressure medium output chamber  57 , and the other side bounds a second control chamber  48  of the control valve arrangement  65  located in the housing  63  of the control valve arrangement  65 . 
     The first control chamber  62  is connected to a pressure medium output  27  of a first solenoid valve  28 ,  29 ,  34 ,  35  via a pressure medium channel  5  located in the housing  4 ,  1  of the operating valve arrangement  66  and provided in the form of a housing channel. The first solenoid valve  28 ,  29 ,  34 ,  35 , which is in the form of a 3/2 way valve, is provided with an inlet valve  28 ,  29  and an outlet valve  34 ,  35 . A pressure medium input  26  of the first solenoid valve  28 ,  29 ,  34 ,  35  is constituted by a pressure medium channel provided in the form of a housing channel located in the housing  4 ,  1  of the operating valve arrangement  66 . The pressure medium input  26  is followed by an additional pressure medium channel  24  located in the housing  4 ,  1  of the operating valve arrangement  66 , and which is also provided in the form of a housing channel, which connects the pressure medium input  26  directly to the pressure medium output chamber  10  of the operating valve arrangement  66 . The inlet valve  28 ,  29  has an inlet seat  28  and a valve closing element  29 , wherein the inlet seat  28  is formed by a ring-shaped projection of the housing  4 ,  1  of the operating valve arrangement  66  surrounding the pressure medium input  26  on a side thereof directed towards the valve closing element  29   
     The valve closing element  29  of the inlet valve  28 ,  29  is biased by the force of a spring  30  against the inlet seat  28 . The outlet valve  34 ,  35  comprises an outlet seat  34  and a valve closing element  35 . The valve closing elements  29  and  35  are constituted by the ends of an armature  32  which acts together with a coil  33 . A pressure medium outlet  36  of the first solenoid valve  28 ,  29 ,  34 ,  35  is connected to the pressure medium outlet  21  of the control valve arrangement  65  via a pressure medium channel  45 , provided in the form of a housing channel located in the housing  63  of the control valve arrangement  65 . 
     The first solenoid valve  28 ,  29 ,  34 ,  35  permits selective connection of the first control chamber  62  of the control valve arrangement  65  to the pressure medium output chamber  10  of the operating valve arrangement  66  or to the pressure medium outlet  21  of the control valve arrangement  65 . The inlet seat  28 , the pressure medium output  27  and the spring  30  of the first solenoid valve  28 ,  29 ,  34 ,  35  are located in a recess  3  of the housing  4 ,  1  of the operating valve arrangement  66 , said recess  3  being located in the side of the wall of the housing  4 ,  1  of the operating valve arrangement  66  adjoining the housing  63  of the control valve arrangement  65 . The recess  3  into which the armature  32  with the valve closing element  29  also extends, thus serves as a seat for part of the first solenoid valve  28 ,  29 ,  34 ,  35 . The coil  33  and the outlet seat  34  of the first solenoid valve  28 ,  29 ,  34 ,  35  are located in a recess  37  in the housing  63  adjoining the housing  4 ,  1  of the operating valve arrangement  66 . 
     A second solenoid valve  38 ,  39 ,  42 ,  41  is located in the recess  37  of the housing  63  of the control valve arrangement  65 , which is also designed as a 3/2 way valve and including an inlet valve  38 ,  39  and an outlet valve  42 ,  41 . The second solenoid valve  38 ,  39 ,  42 ,  41  permits the selective connection of the second control chamber  48  of the control valve arrangement  65  to the pressure medium output chamber  10  of the operating valve arrangement  66  or to the pressure medium outlet  21  of the control valve arrangement  65 . The second solenoid valve  38 ,  39 ,  42 ,  41  is provided with a inlet valve  38 ,  39  comprising an inlet seat  38  and a valve closing element  39 , and with an outlet valve  42 ,  41  comprising an outlet seat  42  and a valve closing element  41 . The valve closing element  41  of the outlet valve  42 ,  41  is biased against the outlet seat  42  by the force of a spring  43 , The valve closing elements  39  and  41  are formed by the ends of an armature  47  which acts together with a coil  46 . A pressure medium input  25  of the second solenoid valve  38 ,  39 ,  42 ,  41  is connected to the pressure medium channel  24  located in the housing  4 ,  1  of the operating valve arrangement  66  via a pressure medium channel provided in the form of a housing channel located in the housing  4 ,  1  of the operating valve arrangement  66 . The pressure medium input  25  of the second solenoid valve  38 ,  39 ,  42 ,  41  is thus also directly connected to the pressure medium output chamber  10  of the operating valve arrangement  66 . A pressure medium output of the second solenoid valve  38 ,  39 ,  42 ,  41  is connected to the second control chamber  48  via a pressure medium channel  44  provided in the form of a housing channel. A pressure medium outlet  40  of the second solenoid valve  38 ,  39 ,  42 ,  41  is connected to the pressure medium outlet  21  of the control valve arrangement  65  via the pressure medium channel  45 . 
     Sealing rings are installed between the sides of the operating valve arrangement  66  facing each other and the control valve arrangement  65  in such manner that they enclose, in the manner of an o-ring seal, the transitional zones from the pressure medium channels of the operating valve arrangement  66  to the pressure medium channels of the control valve arrangement  65 . 
     The functions of the above-described valve arrangements are explained in fiber detail below. 
     When control pressure is fed into the control chamber  6  of the operating valve arrangement  66 , the operating valve arrangement  66  delivers a pressure which is dependent upon the level of the control pressure. The delivered pressure opens the inlet valve  58 ,  56  of the control valve arrangement  65 . The delivered pressure then travels through the control valve arrangement  65  and out of the pressure medium output  55  of the control valve arrangement  65  to the consumer. During this process, the output pressure of the operating valve arrangement  66  flows through the open inlet valve  38 ,  39  of the second solenoid valve  38 ,  39 ,  42 ,  41  and into the second control chamber  48  of the control valve arrangement  65 , thereby maintaining the outlet valve  52 ,  51  in its closed position. 
     If further increase of pressure in the consumer is to be prevented despite further pressure increase in the control chamber  6  and in the pressure medium output chamber  10  of the operating valve arrangement  66 , the first solenoid valve  28 ,  29 ,  34 ,  35  is actuated in such manner that the outlet valve  34 ,  35  thereof is moved into a closed position and the inlet valve  28 ,  29  thereof into an open position. The compressed air then flows into the first control chamber  62  assigned to the inlet valve  58 ,  56  of the control valve arrangement  65  via the first solenoid valve  28 ,  29 ,  34 ,  35 . The inlet valve  58 ,  56  is resultantly moved to a closed position. 
     If the pressure in the consumer is to be lowered without lowering the pressure in the control chamber  6  of the operating valve arrangement  66 , the solenoid valve  38 ,  39 ,  42 ,  41  assigned to the second control chamber  48  of the control valve arrangement  67  is actuated in such manner that the inlet valve  38 ,  39  thereof closes and the outlet valve  42 ,  41  thereof opens. The second control chamber  48  is then vented via the pressure medium outlet  21  of the control valve arrangement  65  and the pressure medium outlet  20  of the operating valve arrangement  66  in communication therewith. The pressure in the consumer is lowered via the outlet valve  52 ,  51  of the control valve arrangement  65  which is then moved to its open position and via the pressure medium outlet  21  of the control valve arrangement  65  and the pressure medium outlet  20  of the operating valve arrangement  66 . 
     If the pressure in the consumer is to be lowered by reduction of the pressure in the control chamber  6  of the operating valve arrangement  66 , the first solenoid valve  28 ,  29 ,  34 ,  35  is also actuated in such manner that the inlet valve  28 ,  29  thereof is moved into its closed position and the outlet valve  34 ,  35  thereof into its open position. As a result, the first control chamber  62  assigned to inlet valve  58 ,  56  of the control valve arrangement  65  is vented via the pressure medium outlet  21  of the control valve arrangement  65  and the pressure medium outlet  20  of the operating valve arrangement  66 . The pressure in the consumer is then lowered via the inlet valve  58 ,  56  of the control valve arrangement  65  which is moved into its open position and via the pressure medium output chamber  10  and the pressure medium outlet  20  of the operating valve arrangement  66 . 
     Turning now to FIG. 2, a valve arrangement is depicted which comprises an operating valve arrangement and a control valve arrangement, and which employs essentially the same design as the valve arrangement shown in FIG.  1 . In the embodiment of FIG. 2, however, the control valve arrangement is not located laterally on the lower housing part  4 , but rather, is provided laterally, in the form of a lid, on the upper housing part  1  of the operating valve arrangement  66 . As such, the disclosure given below is essentially directed only to the differences in arrangement of the control valve arrangement on the operating valve arrangement from that of the valve arrangement according to FIG. 1, and to the partially modified arrangement of the housing channels serving as pressure medium channels. For the sake of greater clarity, the components which are identical to the components shown in FIG. 1 are given the same reference numbers. 
     As mentioned above, the housing  4 ,  1  of the operating valve arrangement  66  comprises a lower housing part  4  and an upper housing part  1  serving as a lid of the housing  4 ,  1 . In the embodiment of FIG. 2, the control valve arrangement  65  is installed on one side of the upper housing part  1 . The control valve arrangement  65  is connected to the operating valve arrangement  66  by means of suitable fasteners, for example, screws. The lower housing part  4  and the upper housing part  1  are designed so that they define the boundary of a step-shaped recess which serves as a seat for the control valve arrangement  65 . 
     The first control piston  53  of the inlet valve  58 ,  56  of the control valve arrangement  65  is formed by a membrane, an outer edge of which is installed between the sides facing each other of an area portion  61  of the upper housing part  1  of the operating valve arrangement  66  and of an area portion  60  of the control valve arrangement  65 , and which is held in place by clamped engagement between these area portions  61  and  60 . The inlet seat  28  of the first solenoid valve  28 ,  29 ,  34 ,  35  is formed by a ring-shaped extension of the upper housing part  1  of the operating valve arrangement  66  which surrounds the pressure medium input  26  on a side thereof directed towards the valve closing element  29 . The pressure medium input  26  of the first solenoid valve  28 ,  29 ,  34 ,  35  and the pressure medium input  25  of the second solenoid valve  38 ,  39 ,  32 ,  41  are connected via a common pressure medium channel  17  to the pressure medium output  9  of the operating valve arrangement  66 . The pressure medium input  64  of the control valve arrangement  65  is connected to the pressure medium output  9  of the operating valve arrangement  66  and the pressure medium outlet  21  of the control valve arrangement  65  is connected via a channel-pressure medium channel  14  directly to the chamber  8  assigned to the pressure medium outlet  20  of the operating valve arrangement  66 . The above-mentioned pressure medium channel  17  is formed by a housing channel provided in the upper housing part  1  and the channel-pressure medium channel  14  is formed by a housing channel of the operating valve arrangement  66  located in the lower housing part  4 . 
     Between the sides of the housing  4 ,  1  of the operating valve arrangement  66  and the housing  63  of the control valve arrangement  65  which face one another, the passages from the pressure medium channels of the operating valve arrangement  66  to the pressure medium channels of the control valve arrangement  65 , as well as the passage from the pressure medium output  9  of the operating valve arrangement  66  to the pressure medium input  64  of the control valve arrangement  65 , are provided with enclosing sealing elements, conveniently in the form of o-rings. 
     The channel-pressure medium channel  14  located in the housing  4 ,  1  of the operating valve arrangement  66  following the pressure medium outlet  21  of the control valve arrangement  65  lets out in the same chamber  8  in which the pressure medium outlet  20  of the operating valve arrangement  66  also lets out. The chamber  8  may be a chamber on the inlet side of a noise suppressor, as described with reference to the figures, or may alternatively be a chamber delimited by a connection piece for the noise suppressor of the operating valve arrangement or any other chamber included as part of the operating valve arrangement  66  connecting the pressure medium outlet  20  to the channel-pressure medium channel  14 . In any event, the pressure medium outlet  21  of the control valve arrangement  65  is connected to the pressure medium outlet  20  of the operating valve arrangement  66 . In all instances, only one noise suppressor is required for the operating valve arrangement  66  and for the control valve arrangement  65 . 
     The solenoid valves  28 ,  29 ,  34 ,  35  and  38 ,  39 ,  42 ,  41  are installed in the recess  37  of the control valve arrangement  65  in such manner that the electrical contact elements of the plug-in device  31  extend essentially at a perpendicular to the upper housing part  1  of the valve arrangement  66 ,  65 . The plug-in device  31  is thus located on the upper part of the valve arrangement  66 ,  65 . 
     Since, as can be clearly seen in both examples of embodiments of the invention, the control chamber  62  for the inlet valve  58 ,  56  of the control valve arrangement  65 , the pressure medium input  26 , the inlet seat  28  and the pressure medium output  27  of the first solenoid valve  28 ,  29 ,  34 ,  35  of the control valve arrangement  65  and also the control chamber  62  of the inlet valve  58 ,  56  of the control valve arrangement  65  are installed with the pressure medium channel  5  connecting the pressure medium output  27  of the first solenoid valve  28 ,  29 ,  34 ,  35  within housing  4 ,  1  of the operating valve arrangement  66 , and since, furthermore, part of the seat of the first control piston  53  is constituted by a area portion  61  of the operating valve arrangement  66 , part of the control valve arrangement  65  is located in the operating valve arrangement  66  or part of the control valve arrangement  65  is constituted by the operating valve arrangement  66 . 
     In accordance with the invention, the complete control valve arrangement  65 , in which the above-mentioned control chamber  62 , the seat for the one control piston  53  and the above-mentioned parts of a solenoid valve  28 ,  29 ,  34 ,  35  are located in the housing  63  of the control valve arrangement  65 , can be installed directly on the operating valve arrangement  66  or in a recess of the operating valve arrangement  66 . Also, in an embodiment of the invention designed in this manner, the pressure medium outlet  21  of the control valve arrangement  65  is connected to the pressure medium outlet  20  of the operating valve arrangement  66 . 
     According to the invention it is also possible to connect the pressure medium outlet  36  of the first solenoid valve  28 ,  29 ,  34 ,  35  and the pressure medium outlet  40  of the second solenoid valve  38 ,  39 ,  42 ,  41  directly to the pressure medium outlet  20  of the operating valve arrangement  66  or to the chamber  8  by means of a pressure medium channel provided in the form of a housing channel. 
     According to the invention, the recess for the control pistons  53  and  49  of the two controlled valves  58 ,  56  and  52 ,  51  can also be formed by area portions of the sides of the operating valve arrangement  66  and the control valve arrangement  65  which face each other. 
     The pressure of the pressure medium output chamber  10  of the operating valve arrangement  66 , as well as the pressure of any other pressure medium source, for example, supply pressure, can be used as control pressure for the two controlled valves  58 ,  56  and  52 ,  51 . 
     The valve arrangement according to the invention can be used in a pneumatic as well as in a hydraulic system, wherein the system may be a motor vehicle braking system or any other installation finctioning with a pressure medium. 
     Having described preferred embodiments of the invention with reference to the accompanying drawing, it is to be understood that the invention is not limited to those precise embodiments, and that various changes and modifications may be effected therein by one skilled in the art without departing from the scope or spirit of the invention as defined in the appended claims.