EP1691083A2 - Hydraulic control device - Google Patents

Abstract

Hydraulic control arrangement (1) comprises an emergency operating valve (8) actuated by hand arranged in a control oil flow path. A directional control valve can be adjusted by the emergency operating valve to a position to actuate the consumer when the pilot valve arrangement (47) is in the base position. An independent claim is also included for a rotary disk valve for the above hydraulic control arrangement. Preferred Features: The emergency control valve shuts off the connection to a pressure reducing valve (30) in its switched positions (a, b). The emergency control valve is a rotary disk valve. The pilot valve arrangement has a pressure limiting valve (32) for limiting the pressure in the control oil flow path.

Description

The invention relates to a hydraulic control arrangement for controlling a consumer according to the preamble of patent claim 1 and a rotary slide valve for a hydraulic control arrangement according to the preamble of patent claim 9.

Such hydraulic control arrangements are used for example in loading cranes and other mobile equipment for controlling hydraulic consumers, such as hydraulic cylinders or hydraulic motors.

DE 199 48 232 A1, for example, shows a hydraulic control arrangement in which connections of a hydraulic cylinder can be connected via a 4/3-way valve to a variable displacement pump or a tank. The directional control valve is actuated by means of electrohydraulic pilot valves and is spring-centered in a middle position in which its pump connection, tank connection and the two working connections of the hydraulic cylinder are shut off from each other. The hydraulic control arrangement fulfills an emergency stop function, since after the failure of the electrical and / or hydraulic supply, the directional control valve assumes its central position by the spring preload and thus an unwanted consumer movement is excluded.

A disadvantage of such hydraulic control arrangements is that after the failure of the electrical and / or hydraulic supply is no longer possible to actuate the directional control valve and thus the

To move consumers, such as a crane, in a safe position, or to ensure emergency operation.

In contrast, the present invention seeks to provide a hydraulic control arrangement and a rotary valve for a hydraulic control arrangement, which allow emergency operation of the consumer.

This object is achieved with regard to the hydraulic control arrangement by the features of patent claim 1 and with respect to the rotary valve by the features of claim 9.

The hydraulic control arrangement according to the invention for controlling a consumer, in particular a mobile working device, has a directional control valve which can be connected by means of a pilot valve arrangement and can be connected to a pump or pressure medium sink (tank). The pilot valve assembly is associated with at least one pressure reducing valve for adjusting a control pressure in a control oil flow path connected to a control space of the directional control valve upon switching the pilot valve assembly from a home position to operate the consumer. According to the invention, the hydraulic control arrangement in the control oil flow path has a manually operable emergency actuation valve, via which the directional control valve in the basic position of the pilot valve arrangement is adjustable to a position to actuate the consumer. About the emergency valve, the directional control valve can be operated even in case of failure of the electrical and / or hydraulic supply. This makes it possible for the consumer, for example a loading crane to move to a safe position, or to ensure emergency operation.

In a preferred embodiment of the invention, the pilot valve assembly has two pilot valves whose output are each connected via a control channel and a pilot line to a control chamber of the directional control valve, wherein the emergency valve opens the connection between the pilot valves to the control chambers in a basic position and shuts off in its switching positions and one of the pilot control lines connects to a pressure medium source.

In its switching positions, the emergency actuation valve preferably blocks the connection to the pressure reducing valve, so that a pressure medium loss during emergency operation of the control arrangement is prevented.

According to the invention, it is preferred to design the emergency actuation valve as a 6/3-way valve, in particular as a rotary slide valve. As a result, the valve by hand and in an emergency in a very short time adjustable without much effort.

In principle, the control arrangement according to the invention is independent of the type of pump. To limit the pressure in the control oil flow path, the pilot control valve arrangement may preferably have at least one pressure relief valve.

As a pressure source is preferably a constant pump at bypass pressure balance use.

In case of failure of the electrical and hydraulic supply, a manually operable auxiliary pump can be connected as a pressure source. About the auxiliary pump is it is possible to generate the hydraulic pressure required for the actuation of the consumers and thereby to enable an emergency operation.

The rotary valve of the invention has a plurality of terminals and switching positions, wherein on a guided in a valve housing rotary valve grooves are formed in each of which a plurality of circumferential portions formed on longitudinal pockets, which can be brought by twisting the rotary valve with different connections in coverage to depending on the switching position on the annular grooves and longitudinal pockets to establish a pressure medium connection between the annular grooves and connections. According to the invention, the angular spacing of the longitudinal pockets arranged on a circumferential section is at least 90 °. As a result, a large sealing surface between the adjacent longitudinal pockets and thus a maximum sealing effect is made possible in order to reduce the leakage losses.

In a preferred embodiment of the invention, the rotary valve has a valve housing with a pressure port, two control input ports, two control output ports and a control pressure port. In a basic position of the rotary valve, the pressure port is connected to the control pressure port and a control input port is connected to a control output port. The control pressure port and the control input port are locked in a first switching position, and the pressure port is connected to the control output port and the control input port is connected to the control output port. In a second switching position, the control pressure port and the control input port are blocked and the pressure port is blocked with the Control output terminal and the control input terminal connected to the control output terminal. One port opens at the end face and the other ports on the circumference into a valve bore receiving the rotary valve. This makes it possible to supply both control chambers of the directional control valve with pressure medium, to adjust this to its switching positions and to move the connected implements and the like in a safe position, or to ensure emergency operation.

The rotary valve valve preferably has two annular grooves defining two annular channels with the valve bore, wherein a first control input port opens into a first annular channel and a first control input port opens in the other second annular channel and the other peripherally opening ports open into the valve bore at an axial distance from the annular channels and in dependence can be connected to the annular channels of the actuating position of the rotary valve on the arranged along the circumference of the rotary valve longitudinal pockets.

The second control input connection opens as an axial connection in an adjacent to the second annular channel rear, bounded by an end face of the rotary valve end portion of the valve bore and the other terminals are preferably formed as radial connections. A first control output connection opens in the region between the annular channels, the second control output connection and the control pressure connection offset by 90 ° open into a front end section adjacent to the first annular channel.

Preferably, in the end face of the rotary valve opens an axial channel, the two perpendicular to each other extending radial bores in the periphery of the front end portion of the rotary valve opens. The radial bores are hydraulically connected to the second control output port in the home position and in a first control position.

In an advantageous embodiment of the invention, two longitudinal pockets extend from the first annular groove into the front end section. A first longitudinal pocket is hydraulically connected in the basic position with the control pressure port and the second longitudinal pocket in a second actuating position with the second control pressure output port. From the first annular groove to the second annular groove, a third longitudinal pocket extends, which in the first setting position is connected to the first control output connection. A fourth and a fifth longitudinal pocket extend from the second annular groove to the first annular groove. The fourth longitudinal pocket is connected in the basic position and the fifth longitudinal pocket in the second switching position to the first control output terminal.

Preferably, the first longitudinal pocket and the second longitudinal pocket by 180 °, the third longitudinal pocket and the fourth longitudinal pocket by 90 ° and the fourth and fifth longitudinal pocket offset by 90 ° to each other, wherein the first longitudinal pocket and the third longitudinal pocket are coaxial. According to the invention, the angular spacing of the longitudinal pockets arranged on a circumferential section is at least 90 °. As a result, a large sealing surface between the adjacent longitudinal pockets and thus a maximum sealing effect is made possible in order to reduce the leakage losses.

The rotary valve preferably has a safety device, which is an adjustment of the Rotary slide from the home position indicates. As a result, the first-time operation of the emergency valve is signaled warned other users of the hydraulic control and the maintenance personnel made aware of the present error of the control arrangement.

It has proved to be particularly advantageous if the safety device has a shear pin which is sheared off during the adjustment of the rotary valve.

At the front end portion of the rotary valve is preferably formed a circumferential groove for receiving a sealing element, in particular a sealing ring in order to reduce the leakage losses.

Preferably, the rear end face of the rotary valve defines a void with an adjacent end face of the valve bore.

Other advantageous developments of the invention are the subject of further subclaims.

• Figur 1 einen Schaltplan einer Ventilscheibe zur Druckmittelversorgung eines ersten und eines zweiten Verbraucheranschlusses;
• Figur 2 eine räumliche Darstellung eines konkreten Ausführungsbeispiels eines erfindungsgemäßen Drehschieberventils und
• Figur 3 eine Schnittdarstellung einer Betätigungsvorrichtung des Drehschieberventils aus Figur 2.

In the following, a preferred embodiment of the invention is explained in more detail with reference to schematic drawings. Show it:

• 1 shows a circuit diagram of a valve disc for pressure medium supply of a first and a second consumer port;
• Figure 2 is a perspective view of a concrete embodiment of a rotary valve according to the invention and
• FIG. 3 shows a sectional illustration of an actuating device of the rotary slide valve from FIG. 2.

FIG. 1 shows a schematic circuit diagram of a control arrangement designed as valve disk 1 for supplying pressure medium to a first consumer port C and a second consumer port D. This essentially consists of a 4/3-way valve 6 actuated via two pilot valves 2, 4 and one as 6/3. Way rotary valve 8 trained emergency valve.

The pressure medium supply of the valve disc 1 takes place in the illustrated embodiment via a pump port P which is connected to a pump, not shown, is conveyed via the pressure medium in a pump line 10. From the pump line 10 branches a bypass line 12 to a tank channel 13, which opens into a tank connection T. In the bypass line 12 a continuously operable inlet pressure compensator 14 is arranged, which is acted upon in the opening direction by the pressure in the pump line 10 and in the closing direction of the highest load pressure of all connected to the load terminals C, D consumers and a spring 16. The highest load pressure is tapped in a known manner via a shuttle valve cascade 18 of all consumers of the system and is connected via a load indicator line 20 to the inlet pressure compensator 14. That is, the control device 1 is designed as a LS (Load Sensing) system, in which the highest load pressure of the driven load via the load reporting line 20 and a LS port LS reported to a pump, not shown, and this is controlled so that in the pump line 10th a certain pressure difference .DELTA.p is above the load pressure lying pump pressure, wherein the Pressure difference Ap of the force of the spring 16 corresponds. From the pump line 10 branches off a further bypass line 22 to the tank channel 13 and the tank port T, in which a primary pressure relief valve 24 is arranged, via which the maximum pressure in the pump line 10 is limited. The pump can be designed as a fixed displacement pump with speed-controlled drive or as a variable displacement pump.

From the pump line 10 further branches a control pressure line 26 for supplying a control pressure source 28 consisting of a pressure reducing valve 30 and a pressure relief valve 32 from. A control output line 34 of the pressure reducing valve 30 is connected to a Steurdruckversorgungsleitung 36 for Redudierung of pending in the control pressure line 26 pump pressure to the maximum control pressure. The control pressure limiting valve 32 is connected to the control pressure supply line 36 and a control pressure relief line 38 to limit the maximum pressure in the control pressure supply line 36. For the control pressure relief line 38, a connection Y is present on the valve disc 1. A connection X to the external control oil supply of the valve disc 1 is closed.

About the 4/3-way valve 6, the pressure medium supply to the load terminals C, D is controlled. This has a pressure port P and two working ports A, B, which in the illustrated spring-biased basic position (0) via a respective drainage restrictor 40 with a tank port T of the directional control valve 6 and connected via the tank line 64 to the tank channel 13 and the tank port T of the valve disc 1 are. The pressure port P of the valve disk 1 is connected to the input port P of Directional valve connected via the pump line 10. In the control positions of the directional control valve 6 identified by (a), a further outflow measuring throttle 40 between the working connection A and the tank connection T of the directional control valve 6 is opened via a control edge. At the control positions indicated by (b), the drainage measuring throttle 40 is located between the working connection B and the tank connection T. The working connections A, B are connected to the consumer connections C and D via two working channels 42, 44. To simplify the explanation, it is assumed that the upper working channel 42 provided with a damping throttle 46 in FIG. 1 is the flow channel, while the lower working channel 44 connected to the consumer port D is the drainage channel. With appropriate switching of the directional control valve 6 then the flow channel to the drainage channel and vice versa.

The control of the 4/3-way valve 6 via the two pilot valves 2, 4, which are designed as electro-hydraulically operated 3/2-way valves and form a pilot valve assembly 47. These are connected to a pressure input P via a bypass line 48 to the control pressure supply line 36, with a tank outlet T via a bypass line 50 with the control pressure relief line 38 and with a control output R via a respective control channel 52, 54 and a pilot line 56, 58, each with a control room 60, 62 of the directional control valve 6 connectable.

According to the invention is in the control oil flow path, that is arranged between the pilot valves 2, 4 and the directional control valve 6, the manually actuable Notbetätigungsventil 8 over which the directional control valve 6 in the illustrated basic position (0) of the pilot valves 2, 4 is adjustable to a position Supplying consumer connections C, D with pressure medium. About the emergency control valve 8, the directional control valve 6 can be operated even in case of failure of the electrical and / or hydraulic supply. This makes it possible to supply the consumer ports C, D with pressure medium and to move connected implements and the like in a safe position, or to ensure emergency operation.

For this purpose, the emergency actuation valve 8 as a 6/3-way rotary valve with a pressure port P two control input terminals X1, X2, two control output terminals Y1, Y2 and a control pressure port Z is executed. The control input terminals X1, X2 are connected via the control channel 52 to the pilot valve 2 and via the control channel 54 to the pilot valve 4. The control output connections Y1, Y2 are connected via the pilot control lines 56, 58 to one of the two control chambers 60, 62 of the directional control valve 6, the pressure connection P to the pump line 10 and the control pressure connection Z to the control pressure line 26.

In the illustrated basic position (O) of the emergency operating valve 8, the control input terminals X1, X2 are respectively connected to the control output terminals Y1, Y2 and the pressure port P is connected to the control pressure port Z. As a result, a control of the directional control valve 6 via the pilot valves 2 and 4 and a pressure medium supply of the control pressure shaft 28 is possible in normal operation of the hydraulic control arrangement.

In case of failure of the pilot valves 2, 4, the directional control valve 6 is due to the spring bias in the illustrated basic position (0), wherein the working channels 42, 44 are connected via a tank line 64 and the tank channel 13 to the tank port T of the control arrangement 1.

This prevents a consumer operation and achieves an emergency stop function.

In order to move the consumer, for example, a crane even in case of failure of the pilot valves 2, 4 in a safe position, or to ensure emergency operation, the directional control valve 6 can be operated even in the event of failure of the electrical and / or hydraulic supply via the emergency control valve 8 , In the event of a failure of the pressure medium source, the pressure required to actuate the consumer can be applied by means of an auxiliary pump (not shown) which can be connected to the pump line 10 or the pressure connection P.

For emergency operation of the directional control valve 6, in a first switching position (a) of the emergency operating valve 8, the control pressure port Z and the control input port X1 are blocked and the pressure port P is connected to the control output port Y1 and the control input port X2 is connected to the control output port Y2. As a result, the control chamber 62 is acted upon by the pump pressure, the directional control valve 6 is adjusted to its switching position (b) and the consumer port D is supplied with pressure medium. In the second switching position indicated by (b), the control pressure port Z and the control input port X2 are disabled, and the pressure port P is connected to the control output port Y2 and the control input port X1 is connected to the control output port Y1. In this switching position of the emergency control valve 8, the control chamber 60 of the directional control valve 6 is acted upon by the pump pressure, the directional control valve 6 in its switching position (a) adjusted and the consumer port C supplied with pressure medium. This makes it possible both Supply consumer connections C, D with pressure medium and to move connected implements and the like in a safe position, or to ensure emergency operation.

The essential difference of the above-described solution to the prior art is thus that the directional control valve 6 can be adjusted even in the event of failure of the pilot valves 2, 4 via the manually operated emergency valve 8.

FIG. 2 shows a concrete exemplary embodiment of a rotary slide valve 8 according to the invention. This has a valve housing 66 with a valve bore 68 and an approximately cylindrical rotary slide 70 guided therein. This has a circumferential groove 74 at a front end section 72 for receiving a sealing ring 76 (see FIG ) and merges into a likewise cylindrical handling section 78 with a smaller diameter. The rotary valve 8 has the pressure port P, two control input ports X1, X2 and two control output ports Y1, Y2 and a control pressure port Z, wherein the control input port X2 frontally into the rotary valve 70 receiving valve bore 68 and the control input terminal X1, the control output terminals Y1, Y2, the Pressure port P and the control pressure port Z circumferentially open in the valve bore 68. A rear end face 80 of the rotary valve 70 defines an empty space 84 with an adjacent end face 82 of the valve bore 68.

On the rotary valve 70, two annular grooves 86, 88 are formed, which define two annular channels 90, 92 with the valve bore 68, wherein in the first annular channel 90 of the pressure port P and in the other second annular channel 92nd a first control input terminal X1 opens and the other peripherally opening ports Y1, Y2, Z open at an axial distance from the annular channels 90, 92 in the valve bore 68.

The second control output terminal X2 opens as an axial connection in an adjacent to the second annular channel 92 rear end of the end face 80 of the rotary valve 70 limited end portion 94 of the valve bore 68. The first control control output port Y1 opens in the area between the annular channels 90, 92 of the second Steuerausgangsanschuss Y2 and the by 90 ° offset control pressure port Z in the first annular channel 90 adjacent the front end portion 72 of the rotary valve 70 a.

In the end face 80 of the rotary valve 70, an axial channel 96 is formed, which opens via two mutually perpendicular radial bores 98, 100 in the periphery of the front end portion 72 of the rotary valve 70. The radial bores 98, 100 are hydraulically connected to the second control output port Y2 in the home position (0) and in a first control position (a) of the rotary valve 70.

Starting from the first annular groove 86, two longitudinal pockets 102, 104 extend into the front end portion 72 of the rotary valve 70. In the basic position (0) of the rotary valve 70, the first longitudinal pocket 102 is hydraulically connected to the control pressure port Z and the second longitudinal pocket 104 is hydraulically connected to the second control pressure output port Y2 in a second actuating position (b). From the first annular groove 86 to the second annular groove 88, a third longitudinal pocket 106 extends, which in the first setting position (a) is connected to the first control output connection Y1. A fourth Longitudinal pocket 108 and a fifth longitudinal pocket 110 extend from the second annular groove 88 toward the first annular groove 86, wherein the fourth longitudinal pocket 108 in the basic position (0) and the fifth longitudinal pocket 110 in the second switching position (b) is connected to the first control output terminal Y1 , The longitudinal pockets 102 to 110 extend along the rotary valve surface and have an approximately rectangular basic shape, which is rounded in the region of the terminals in each case arcuately.

The first longitudinal pocket 102 and the second longitudinal pocket 104 are arranged by 180 °, the third longitudinal pocket 106 and the fourth longitudinal pocket 108 by 90 ° and the fourth longitudinal pocket 108 and fifth longitudinal pocket 110 offset by 90 ° to each other. The first longitudinal pocket 102 and the third longitudinal pocket 106 are coaxial with each other. That the angular distance of the arranged on a peripheral portion longitudinal pockets is at least 90 °. As a result, a large sealing surface between the adjacent longitudinal pockets and thus a maximum sealing effect is made possible in order to reduce the leakage losses.

In principle, the connections and the longitudinal pockets can also be arranged at other angular intervals in the valve housing or in the rotary valve.

In the illustrated basic position (O) of the emergency operating valve 8 (0 ° position), the control input terminals X1, X2 are respectively connected to the control output terminals Y1, Y2 and the pressure port P is connected to the control pressure port Z. Thus, in normal operation of the hydraulic control arrangement 1, a control of the directional control valve 6 via the pilot valves 2, 4 and a pressure medium supply of the control pressure source 28 is possible (see Figure 1).

For emergency operation of the directional control valve 6, the control pressure port Z and the control input port X1 are locked and the pressure port P is connected to the control output port Y1 and the control input port X2 is connected to the control output port Y2 in a first shift position (a) of the emergency operating valve 8 (-90 ° position). As a result, the control chamber 62 is acted upon by the pump pressure, the directional control valve 6 is adjusted to its switching position (b) and the consumer port D is supplied with pressure medium (see FIG. 1). At the second switching position of the emergency operating valve 8 (90 ° position) indicated by (b), the control pressure port Z and the control input port X2 are blocked and the pressure port P is connected to the control output port Y2 and the control input port X1 is connected to the control output port Y1. In this switching position of the emergency control valve 8, the control chamber 60 is acted upon by the pump pressure, the directional control valve 6 in its switching position (a) adjusted and the consumer port C supplied with pressure medium. That in the switching positions (a), (b) of the rotary valve 8, it is possible to supply the consumer ports C, D with pressure medium and to move connected implements and the like in a safe position, or to ensure emergency operation.

According to Figure 3, which shows a sectional view of an actuator 114 of the rotary valve 8, this has an operating handle 116 with an approximately hollow cylindrical body 118 which forms a holding portion 124 of reduced diameter on a housing cover 120 of the valve housing 66 facing end portion 122. The holding portion 124 has at its inner periphery 126 a front side annular projection 128 which engages behind a mushroom-shaped projection 130 of the housing cover 120 and rotatably defines the operating handle 116 on the housing cover 120. The housing cover 120 is rotatably screwed to the valve housing 66 and the operating handle 116 rotatably connected to the cylindrical handling portion 78 of the rotary valve 70.

At the front end portion 72 of the rotary valve 70, a circumferential groove 74 for receiving the sealing ring 76 is formed to prevent leakage from the limited by the housing cover 120 and the rotary valve 70 annular space 132 to the outside.

The rotary valve 70 is fixed in the illustrated basic position (0) by a spring 136 loaded ball 138, which is inserted into a radial blind hole 140 of the housing cover 120. The spring-loaded ball 138 exits from the blind hole 140 sections and gangs in a recess 142 of the rotary valve 70 a.

In the handling portion 78, a radially projecting stop pin 144 is inserted, which extends in a non-circumferential groove 146 of the housing cover 120 and limits the adjustment of the rotary valve 70 to + 90 ° to -90 °. As a result, the two rotated switching positions of the rotary valve 70 are defined.

Disclosed is a hydraulic control arrangement 1 for controlling a consumer, in particular a mobile working device, which can be connected via a pre-pilot valve arrangement 47 piloted directional control valve 6 with a pump or a Druckmittelsenke (tank), wherein the pilot valve assembly 47th at least one pressure reducing valve 30 for adjusting a control pressure in a control oil flow path, which is connected to a control chamber 60, 62 of the directional control valve when switching the pilot valve assembly 47 from a home position (0) to actuate the consumer. According to the invention, a manually actuable emergency actuation valve 8 is arranged in the control oil flow path, via which the directional control valve 6 in the basic position (0) of the pilot valve arrangement 47 can be adjusted to a position in order to actuate the consumer.

LIST OF REFERENCE NUMBERS

1

control arrangement

2

pilot valve

4

pilot valve

6

way valve

8th

Rotary valve

10

pump line

12

bypass line

13

tank channel

14

Inlet pressure

16

feather

18

Cascade of shuttle valves

20

Load-sensing line

22

bypass line

24

Primary pressure relief valve

26

Control pressure line

28

Control pressure source

30

Pressure reducing valve

31

Return line

32

Pressure relief valve

33

control spring

34

Control output line

36

Control pressure supply line

38

Control pressure relief line

40

orifice

42

working channel

44

working channel

46

damping throttle

47

Pilot valve arrangement

48

Steuerölzuführleitung

50

Pilot oil tank line

52

control channel

54

control channel

56

pilot line

58

pilot line

60

control room

62

control room

64

tank line

66

valve housing

68

valve bore

70

rotary vane

72

front end section

74

circumferential groove

76

sealing ring

78

handling section

80

back face

82

front

84

whitespace

86

first ring groove

88

second annular groove

90

annular channel

92

annular channel

94

rear end section

96

axial

98

radial bore

100

radial bore

102

first longitudinal pocket

104

second longitudinal pocket

106

third long pocket

108

fourth longitudinal pocket

110

fifth long pocket

112

peripheral portion

114

actuator

116

operating handle

118

body

120

housing cover

122

end

124

maintenance section

126

inner circumference

128

head Start

130

head Start

132

annulus

134

vent hole

136

feather

138

Bullet

140

Blind hole

142

recess

144

shear pin

146

groove

Claims (18)

Hydraulic control arrangement (1) for controlling a consumer, in particular a mobile working device, which is connectable via a by means of a pilot control valve arrangement (47) directional control valve (6) with a pump or a Druckmittelsenke (tank), wherein the pilot valve assembly (47) at least one pressure reducing valve (30) for setting a control pressure in a control oil flow path that is connected to the switching of the pilot valve assembly (47) from a basic position (0) with a control chamber (60, 62) of the directional valve (6), in order to operate the consumer, characterized in that in that a manually operable emergency actuation valve (8) is arranged in the control oil flow path, by means of which the directional control valve (6) in the basic position (0) of the pilot valve arrangement (47) can be adjusted to a position in order to actuate the consumer. Control arrangement according to claim 1, wherein the pilot control valve arrangement (47) has two pilot valves (2, 4) whose outlet (R) is in each case controlled via a control channel (52, 54) and a pilot control line (56, 58) having a control chamber (60, 62). the directional control valve (6) are connected, wherein the Notbetätigungsventil (8) in a basic position (0) opens the connection between the pilot valves (2, 4) to the control chambers (60, 62) and in its switching positions (a, b) shuts off and one of the pilot control lines (56, 58) connects to a pressure medium source. Control arrangement according to claim 1 or 2, wherein the emergency actuation valve (8) in its switching positions (a, b) shuts off the connection to the pressure reducing valve (30). Control arrangement according to one of the preceding claims, wherein the emergency actuation valve (8) is a 6/3-way valve. Control arrangement according to one of the preceding claims, wherein the emergency actuation valve (8) is a rotary slide valve. A control arrangement as claimed in any one of the preceding claims, wherein the pilot valve assembly (47) has at least one pressure relief valve (32) for limiting the pressure in the control oil flow path. Control arrangement according to one of the preceding claims, wherein the pressure source is a fixed displacement pump with inlet pressure compensator. Control arrangement according to one of the preceding claims, wherein a manually operable auxiliary pump can be connected as a pressure source. Rotary slide valve (8), in particular for a hydraulic control arrangement (1) according to one of the preceding claims, having a multiplicity of connections (X1, X2, Y1, Y2, Z, P) and switching positions (a, 0, b), wherein on one In a valve housing (66) guided rotary valve (70) annular grooves (86, 88) are formed, in each of which a plurality of circumferential portions formed on longitudinal pockets (102 to 110) open, by turning the rotary valve (70) with different terminals (Y1 , Y2, Z) can be brought into overlap to a pressure medium connection between the annular grooves (86, 88) and terminals (Y1 , Y2, Z) nerstellt, characterized in that the angular distance of the arranged on a peripheral portion longitudinal pockets (102 to 110) is at least 90 °. Rotary slide valve according to claim 9, comprising a valve housing (66) with a pressure port (P), two control input ports (X1, X2) and two control output ports (Y1, Y2) and a control pressure port (Z), wherein in a basic position (0) the pressure port (P) P) is connected to the control pressure port (Z) and in each case a control input port (X1, X2) to a control output port (Y1, Y2) and in a first switching position (a), the control pressure port (Z) and the control input port (X1) are locked and the pressure port (P) is connected to the control output port (Y1) and the control input port (X2) is connected to the control output port (Y2), and in a second switching position (b) the control pressure port (Z) and the control input port (X2) are disabled and the pressure port (P) to the control output terminal (Y2) and the control input terminal (X1) are connected to the control output terminal (Y1), the terminal (X2) frontal tig and the other connections (X1, Y1, Y2, P, Z) circumferentially in a rotary valve (70) receiving the valve bore (68) open. Rotary slide valve according to claim 10, having two annular grooves (86, 88) which delimit two annular channels (90, 92) with the valve bore (68), wherein in one first annular channel (90) the pressure port (P) and in the other second annular channel ( 92), a first control input terminal (X1) opens and the other peripherally opening connections (X1, Y1, Y2, P, Z) at an axial distance to the annular channels (90, 92) open into the valve bore (68) and in dependence on the setting position ( a, 0, b) of the Rotary slide (70) via the at the periphery of the rotary valve (70) arranged longitudinal pockets (102 to 110) with the annular channels (90, 92) are connectable. Rotary slide valve according to claim 11, wherein the second control input connection (X2) as axial connection (96) in a second annular channel (92) adjacent the rear, of an end face (80) of the rotary valve (70) limited end portion (94) of the valve bore (68) opens and the other terminals are formed as radial terminals (X1, Y1, Y2, P, Z), wherein a first control output terminal (Y1) in the area between the ring channels (90, 92), the second control output terminal (Y2) and by 90 ° offset control pressure port (Z) in a first annular channel (90) adjacent the front end portion (72) open. Rotary slide valve according to claim 12, wherein in the end face (80) of the rotary valve (70) an axial channel (96) opens, which via two mutually perpendicular radial bores (98, 100) in the periphery of the front end portion (72) of the rotary valve (70) opens wherein these are hydraulically connected to the second control output terminal (Y2) in the home position (0) and in a first parking position (a). Rotary slide valve according to claim 13, wherein two longitudinal pockets (102, 104) extend from the first annular groove (86) into the front end section (72), a first longitudinal pocket (102) in the basic position (0) being connected to the control pressure port (Z). and the second elongate pocket (104) is hydraulically connected to the second control pressure output port (Y2) in a second parking position (b), and wherein a third longitudinal pocket extends from the first annular groove (86) to the second annular groove (88) (106) connected to the first control output terminal (Y1) in the first setting position (a), and fourth and fifth longitudinal pockets (108; 110) extending from the second annular groove (88) toward the first annular groove (86). extend, wherein the fourth longitudinal pocket (108) in the basic position (0) and the fifth longitudinal pocket (110) in the second switching position (b) with the first control output terminal (Y1) are connected. A rotary valve valve according to claim 14, wherein the first longitudinal pocket (102) and the second longitudinal pocket (104) extend through 180 °, the third longitudinal pocket (106) and the fourth longitudinal pocket (108) through 90 ° and the fourth and fifth longitudinal pockets (108; 110). offset by 90 ° to each other, wherein the first longitudinal pocket (102) and the third longitudinal pocket (106) extend coaxially with each other. Rotary slide valve according to one of the claims 9 to 15, wherein the rotary valve (70) at the front end portion (72) has a circumferential groove (74) for receiving a sealing element (76), in particular a sealing ring. Rotary slide valve according to one of the claims 9 to 16, wherein the rear end face (80) of the rotary valve (70) defines an empty space (84) with an adjacent end face (82) of the valve bore (68). Rotary slide valve according to one of the claims 9 to 17, wherein a positioning element (138), preferably a spring-loaded ball, fixed in the basic position (0) of the rotary valve (70).

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