DE3139635A1 - Hydraulic control device with at least two directional control valves for controlling hydraulic consumption units - Google Patents

Description

3. 17389

25.9.1931 My /? I

λΟΒΞΞ? 305CH C-M3H, 7000 Stuttgart 1

Hydraulic control device with at least two directional control valves for controlling hydraulic consumers

State of the art

The invention is based on a hydraulic control device with at least two directional control valves hydraulic consumer. Ss is already such a control device from DE-OS 27 22 238 "known" in which several Directional valves for controlling the hydraulic consumers of a Kubstackler are switched in a neutral circulation and supplied with pressure medium via a multi-way flow regulator. With this control device there is one thing Lifting function assigned directional control valve downstream of the directional control valves assigned to the constant flow in neutral circulation, its pump connection except with the neutral circulation is connected to the current regulator via a long residual current channel. This control device has the Disadvantage that, in addition to the IT-neutral circulation, they have a the entire control device pulling through the residual flow channel required, which is both the design and the size of the Control device adversely affected. Due to the position of the one that controls the total current and is intended for the lifting function Directional control valve downstream of the other

valves in the neutral circulation is suitable, this control device not for larger input currents, as the upstream constant-flow directional control valves are used in such a case Neutral circulation would cause too great a resistance. Above all, this control device has the disadvantage that it "Unsatisfactory for certain movements on the forklift functions. Are z. B. in the required for forklifts parallel actuation of the tilt function and the Lifting function a directional valve assigned to the constant flow and a directional valve assigned to the residual flow are actuated at the same time and the constant current consumer moves against the stop (tilt cylinder y against the stop, so there is no constant current more pulled over the 'current regulator and this interrupts also the residual current. All of the pressure medium delivered by the pump must now be passed through the pressure relief valve Drain the tank. This not only leads to a sudden stop in the lifting function, but also to energy losses. The forklift operator then moves the tilting function in the usual way Directional valve returns to its central position, so the entire amount of pressure medium can be transferred via the Ueutralumlauf the directional control valve controlling the lifting function flow to the cylinder, causing another sudden movement the load leads. Furthermore, this control device also has the disadvantage that it is difficult to expand for processing additional pressure medium flows.

Furthermore, DE-OS 2 939 327 discloses a control device known, which represents a further development of the aforementioned control device and with which an increased pressure medium flow can be controlled to a constant current consumer. The disadvantage here is that instead of one standard 6/3-way valve a specially designed directional valve must be used, which in the working position a throttled connection between the neutral circulation

Has conclusion and the consumer connection. Furthermore this control device has essentially the same disadvantages as the aforementioned device.

Advantages of the invention

The control device according to the invention with the characterizing Features of the main claim has the advantage that a constant flow sweeping valve penetrating Residual flow channel is omitted. The control device can thus be built in a simpler and more compact manner. Furthermore, from The advantage that when the directional control valve assigned to the total flow is actuated, the total flow does not pass through the neutral circulation is performed with the constant flow directional control valves located therein. Especially when two functions are operated in parallel is this beneficial. Furthermore, this control device can be expanded particularly easily to the effect that that it can process additional pressure medium flows. In addition, it is also suitable for processing increased inlet pressure medium flows. In addition, the control device is suitable for better and low-impact control the functional processes, as they are in particular with forklifts appear. For example, with parallel operation of a constant current consumer and a residual current consumer with subsequent Interruption of the total current consumption, which is the residual current controlling directional valve continue to be supplied with pressure medium. Furthermore, in the control device arrange further block valves for additional functions without changing the position of the connections for inlet and return changes.

By the measures listed in the subclaims Advantageous developments and improvements of the control device specified in the main claim are possible. A training according to the requirements is particularly advantageous

Proverbs 6 to 7, whereby the control device can be expanded in a simple manner so that it has an additional Can process pressure medium flow, this being done in a particularly energy-saving manner. According to claim 10 leaves A particularly simple and compact design of the control device can be achieved. Other, particularly advantageous Refinements result from the remaining claims of the description and the drawing.

drawing

Embodiments of the invention are shown in the drawing and explained in more detail in the description below. 1 shows a simplified representation of a first control device, FIG. 2 shows part of a second control device for processing an additional pressure medium flow when supplied by a single pressure medium pump, FIG. 3 shows a longitudinal section through the control device according to FIG. 2 and FIG. H shows part of a third control device with ' a pressure medium supply with two pumps.

Description of the exemplary embodiments

FIG. 1 shows a control device 10 which has a first (11), a second (12), a third (13) and a fourth directional valve (1 ¹ O. The first and second directional valves 11, 12 are in a common housing 15 summarized, while the third and fourth directional control valve 13 and Ik are designed as separate block valves which are flanged between the housing 15 and an end plate 16. In the housing 15s cLas also accommodates a flow regulator 17, an inlet 19 connected to a pump 18 and an outlet 22 connected to a tank 21. The control device 10 is used to control the hydraulic consumers in a forklift truck.

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"or residual flow assigned first directional valve 1 1 controls the Hetenfunction, while the second directional valve 12 controls a tilting function. The third and fourth directional valve 13 j " \ h can be used for additional functions, such as. B. Clamping and pivoting. The second to fourth directional valves 12, 13, 1 k are identical to one another and are designed as 6/3 directional valves. The second and third directional control valve 12, 13 are used to control a constant flow, while the fourth directional control valve lh is arranged in a blocking circuit to control an increased pressure medium flow. While the directional control valves 12, 13 and 1U are intended to control double-acting functions, the first directional control valve 11 is only used to control a single-acting function.

The first directional valve 11 assigned to the lifting function has an inlet connection 23 which is connected to the inlet 19 via a load-securing check valve 2k and an inlet channel 25. A return connection 26 is connected to the outlet 22 via a return channel 27. To control the single-acting function, the directional control valve 11 has only a single consumer connection 28. Furthermore, the first directional control valve 11 has a first (29) and a second circulation connection 31 with which it is connected to a neutral circulation channel 32 which is led from the pump 18 via all directional control valves 11 to 1U and the end plate 16 to the tank 21. Furthermore, the first directional control valve 11 has a first (33) and a second switching connection 3 ^, of which the first (33) is connected via a residual flow channel 35 to a residual flow outlet 36 of the flow regulator 17. From the second switching connection 3 ^ a drain channel 37 leads to the outlet 22. Furthermore, a first (38) and a second control connection (39) are formed on the directional control valve 11, of which the latter (39) via a control line Μ to the neutral circulation channel 32 in the area between the second (12) and the third directional control valve 13 is relieved. A control slide k2 assigned to the directional valve 11 has a central position k3 in which it is the

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Consumer connection 28 from the inlet connection 23 and the return connection 26 separates, while he separates the respective circulation connections 29, 31 »the switching connections 33, 31 * and the control connections 38, 39 each connects to one another. In a first working position It-Ii- of the control slide associated with lifting 1 + 2 is the consumer connection 28 with the inlet connection 23 connected, while all other connections are blok-1: are marked. In a second working position 59 of the control slide 1 * 2 associated with lowering, the consumer connection 28 to the return connection 26 relieved, the inlet connection 23 blocked, while the other connections are connected to each other as in the middle position 1 * 3.

The flow regulator 17 has one in addition to the residual flow outlet 36 Constant current outlet 1 * 5, to which via a supply line Ö6 the second (12) and third directional control valve 13 with their inlet connections 23 are connected in parallel. Those assigned to the Stromregier3i7S2, its control element 1 * 7 with its pressure difference loading choke 1 * 8 is in a first ■ supply channel 1 * 9, which is a first input 51 of the current regulator 17 connects to the neutral circulation channel 32 and thus to the inlet 19. A second input 52 of the current regulator 17 is connected to the inlet channel via a second supply channel 53 25 and thus with the inlet 19 in connection. The inlet 19 is for maximum pressure limitation via a first Pressure relief valve 5I * secured. For pressure protection the intrinsic function at a lower pressure level, a second pressure relief valve 55 is provided, which can pre-control the control element 1 * 7 of the current regulator 17 and its outlet 56 with the first control connection 38 of the first directional control valve 11 is connected.

In contrast to the first directional valve 11, the directional valves 12, 13 and 11 * are used to control a double-acting function provided and designed accordingly in each case with a second consumer connection 57. Otherwise are appropriate Connections and working positions as in the

Most sweeping valve 11 is also provided with the same reference numerals.

The fourth directional valve 1 ^ is switched to the blocking circuit, for which purpose the supply line U-6 is interrupted by a plug 58 -will. At the same time, the inlet to the connection 23 and the associated neutral circulation channel 32 connected to one another at connection point 59.

The mode of operation of the control device 10 is explained as follows:

If all directional control valves 11 to 1 h are in their respective middle positions ^ 3, the pressure medium delivered by the pump 18 into the inlet 19 flows via the neutral circulation channel 32 and the end plate 16 back to the tank 21. Via the flow regulator throttle ij-8 flows no pressure medium flow, so that the control member kj of the flow regulator 17 is held by the force of a spring in the initial position shown, in which the connection to the residual flow channel 35 is blocked. In any case , the supply line h6 is hydraulically blocked by the control slide of the directional control valves 12, 13, lh and by the plug 58.

If now one of the actuated the constant current associated directional control valves "12 or 13, so the neutral circulation channel 32 is interrupted. The current regulator 17 with its externally of the control member lj-7 arranged throttle UQ now leads a constant current in the supply line k6, while the excessive Eeststrom leads into the residual flow channel 35. With the constant flow, the second directional valve 12 can now control the tilting function alone or a clamping function can be exercised with the third directional valve 13. The two functions figuring and clamping can, however, also be carried out simultaneously Directional control valve

12 controlled, the pressure reduction is carried out by the second pressure limiting valve 55, which precontrols the control element kj of the flow regulator 17 and thus leads to a precontrolled pressure limiting function. The control oil outflow from the second pressure relief valve 55 takes place from its outlet 56 via the control connections 38, 39, which are open in the middle position k.3 of the first directional valve 11, to the control line ^ 1 and further via the neutral circulation channel 32 to the tank 21. The pressure reduction for the D function takes place on one significantly lower pressure level and is therefore only effective if the second directional control valve .12 is operated alone. When the control slide 1 + 2 of the first directional control valve 11 is not actuated, the residual current conducted by the flow regulator 17 into the residual flow channel 35 flows back to the tank 21 via its switching connections 33, 3k and the drainage channel 37. If the constant current carried by the flow regulator into the supply line ^ 6 The second pressure relief valve 55 is ineffective because its outlet 56 is pressurized by the pressure in the neutral circulation channel 32 via the control line kl and the first directional valve 11 in the middle position k3. The maximum pressure limit for the consumer of the third directional valve 13 thus takes over the first pressure relief valve 5 ^ _s is set to over the second pressure relief valve 55 significantly higher value.

If the fourth directional control valve 1 k is operated by itself for the pivoting function, it controls the total pressure medium flow arriving via the neutral circulation channel 32 and conveyed by the pump 18 to the associated consumer Section of the neutral circulation channel 32 is connected to the inlet connection 23, while the associated supply line k6 of the valve Ik through the

173 8

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Plug 58 is blocked. Due to the blocking circuit of the fourth directional valve 1U, additional directional valve blocks can be added for additional functions between the end plate and the directional valve 1U, these valves also being operated in parallel and with the total current. In this case, the pressure relief via the first pressure-limiting valve 5 ^ ·· carried A certain parallel operation of the fourth directional control valve 1 k with the other directional control valves 11 to 13 is possible as long as the Keutralumlaufkanal 32 is not fully closed, as shown in the fine control range of the case. By appropriately positioning the directional valve Ik realizing the blocking circuit and the plug 58, the number of directional valves that are supplied with the constant current of the current regulator 17 can be increased or decreased as required.

If, when the first directional control valve 11 is actuated individually, its control slide k-2 is deflected into its first working position j, the neutral circulation channel 32 is interrupted and the entire pressure medium conveyed by the pump 18 flows via the inlet channel 25 and the control slide h-2 to the consumer connection 28 There is no flow of pressure medium flowing through the flow regulator 17. If, however, ^ brought to a lowering of the lifting cylinder connected to the control slider * 2 in its second operating position 50, the Heutralumlaufkanal 32 is not interrupted and downstream paths valves 12 to 1 h can be actuated independently of parallel.

Are now in the usual parallel operation of the lifting and tilting functions in the forklift truck, the first directional control valve 11 and If the second directional control valve 12 is actuated at the same time, the current regulator 17 leads the constant current via the second directional control valve 12 to the e-cylinder, while the residual flow via the inlet channel 25 to the consumer connection 28 on the first directional valve 11

is guided 'and is available for lifting the lifting cylinder. In this parallel operation of the directional control valves 11 and 11, the pressure limiting valve 5 ^ is effective for maximum pressure protection, while the second pressure limiting valve 55 is ineffective for the tilting function. If the constant flow from flow regulator 17 to second directional control valve 12 is interrupted in this parallel operation, for example because the connected tilt cylinder moves against a stop, the pressure difference across flow regulator throttle kQ is omitted, causing control element kj in flow regulator to move into the initial position shown by spring force is moved. The total, delivered by the pump 18 pressure fluid flow thus flows through the inlet duct 25 and the control slide k2 of the first directional valve 11 to the consumer port 28. This ensures _s that upon interruption of the constant current decrease through the second directional control valve 12 controlled by the first directional control valve 11 lifting function does not is interrupted. Instead of the original residual current, only the total current flows from the pump 18 to the connected lifting cylinder. The full flow of pressure medium via the first directional valve 11 to the consumer connection 28 for the lifting function is also maintained when the operator of the forklift recognizes the tilting cylinder that has hit the stop and then returns the second directional valve 12 to its central position ^ 3. It is thus ensured that the load carried by the forklift truck is not moved abruptly, regardless of the respective functional sequences, which can lead to the risk of accidents. The arrangement of the first directional control valve 11 assigned to the lifting function in the neutral circulation channel 32 upstream of the directional control valves 12, 13 assigned to the constant-current consumer enables safe and low-vibration control of the hydraulic consumers of the forklift truck. In addition, this control device 10 works with fewer energy losses and can also be implemented in a relatively simple and compact manner. In addition, it does not require a residual flow channel that goes through all the constant flow valves and emanates from the flow regulator. In addition, can

this control device can also be designed for large input currents and for different applications "in particular can be easily adjusted.

FIG. 2 shows part of a second control device TO which is suitable for processing a second constant current, the pressure medium being supplied by a single pump. The second control device 70 according to FIG. 2 differs from the control device according to FIG. 1 essentially as follows, the same reference characters being used for the same components. In the neutral circulation channel 32, an additional throttle 71 is connected between the inlet 19 and the circulation connection 29 of the first directional control valve 11, which is in series with the flow regulator throttle kQ . Furthermore, a return connection 72 is formed on the flow regulator 17, which is relieved directly to the tank 21 and, when the control member 1 * 7 is maximally deflected, counter to the. Has spring force with the second input 52 connection.

FIG. 3 now shows a longitudinal section through a structurally designed, second control device 70 according to FIG. 2. The same components as in FIG. 2 are also named in FIG. 3 with the same reference numerals. As Figure 3 clearly shows, the first directional control valve 11 and the second directional control valve 12 and the flow regulator 17 are combined in the housing. , The control slide ^ 2 of the first directional valve 11 is tight and slidably guided in a longitudinal bore 73 in which the nine connections of the first directional control valve T1 formed by ring-shaped extensions, also nine chambers are. These chambers are provided with the same reference numbers corresponding to the connections, but with the index Apostrophe. In the longitudinal bore 73 is thus next to an inlet chamber 23 ', a consumer chamber 28' and next to it the Return chamber 26 'arranged. On the other side of the inlet chamber 23 'accordingly borders a first switching

chamber 33 'and on it a z-wide switching chamber 3 ^'. Adjacent the latter (3 ^ ') is followed by a first circulation chamber 29'j a second circulation chamber 31 'and a first 38' and a second control chamber 39 '

The control slide k2 of the second directional valve 12 slides in a corresponding manner in a second longitudinal "bore 7 ^ in which the pump chamber 23 ', the consumer chamber 28' and the return chamber 26 'are formed in a manner corresponding to that of the first directional valve. As a result of the double-acting function the second directional valve 12 is further comprising a second load chamber 57 'next to the second return chamber 26' is provided. adjacent to the latter, the first and second circulation chamber 29V ₅ 31 'is formed. further, as Figure 3 shows in greater detail, the second switching chamber 3h' on Drain channel 37 is connected to the return chamber 26 'of the second directional valve 12. Furthermore, the switching chambers 29', 31 'of both directional valves 11, -12 are located in the neutral circulation channel 32. Furthermore, the control line Ut leads from the second control chamber 39' in the first directional valve 11 to the neutral circulation channel 32 downstream of the second directional control valve 12.

Furthermore, the control member ^ 7 of the current regulator 17 is guided in a third longitudinal bore 75 in the housing 15. In this case, the additional throttle 71 formed in the neutral circulation channel 32 is implemented by an externally adjustable screw 76. The current regulator throttle k8 is formed by an annular collar 77 on the control member U7 in connection with the longitudinal bore 75. The pressure medium flow downstream of the flow regulator throttle U8 and thus in the inlet 51 is guided via a throttle bore 78 arranged in the control member! +7 into a pressure chamber 81 which accommodates a spring 79. The pressure medium flow to the constant flow outlet U5 is throttled with the aid of first control edges 82, while at the other end of the same piston section on the control member

kj for throttling the residual flow Steierkanten 83 are provided. Furthermore, an additional control surface 81 is provided on the same piston section of the control member h-7 in the area between the two control edges 82, 83, which is necessary for the operation of the control member hj as a pilot-operated pressure relief valve. Via the control surface 8 ^ the control element ^ 7 can relieve the residual flow outlet 36 and thus at the same time also the opened second input 52 directly to the return connection 72 with a correspondingly strong deflection against the force of the spring 79. For the aforementioned pilot-operated pressure-limiting function, the pressure chamber receiving the spring is secured by the second pressure-limiting valve 55, the outlet 56 of which is connected to the first control chamber 38 'of the first directional control valve 11. In addition, the same pressure chamber 81 can be relieved towards the outlet 22 through the first pressure limiting valve 5 ^. Instead of the directly controlled pressure limiting function according to FIG. 2, the maximum pressure limiting is shown here in a pilot-controlled manner in FIG.

The mode of operation of the control device 70 according to FIG. 2 is explained as follows, it being assumed that a third and fourth directional control valve 13, 1h and the end plate 16 are flanged to the control device 70 as in FIG. The mode of operation of the second control device 70 differs from that of the first control device 10 mainly in that when the directional control valves 11 to Ik are not actuated, the entire pressure medium flow conveyed by the pump 18 no longer flows through the neutral circulation channel 32, but rather a flow from the additional throttle 71 determined second constant current. That. The pressure drop caused by the additional throttle 71 counteracts the force of the spring 79 on the control element kj of the flow regulator 17 and deflects it so far that the excess residual flow via the second supply channel 53 and the flow regulator 17 in

the residual flow channel 35 and via the first directional control valve 11 into the drainage channel 37 is controlled. If the flow rate of the pump 18 is very high, the control element "^ T can open even further and finally relieve the second input 52 directly to the return connection 72. The second constant flow determined by the additional throttle 71 is therefore smaller than the flow rate of the pump 18 in terms of its size , but still greater than the first constant current that the current regulator 17 leads to the priority-supplied constant-current directional control valves 12 and 13 ″ when required. The size of this first constant current is now determined by the cumulative effect of the additional throttle 71 and the current regulator throttle kQ . The size of both constant currents can be set with the aid of the adjustable additional throttle 71. This second, large constant current can be used to supply the fourth directional valve lh, whose associated consumer, such as the slewing gear, has an increased pressure medium flow requirement The lifting function controlled by the first directional valve 11 work with the entire delivery flow of the pump 18, which can now be designed to be very large since it does not have to flow via the neutral circulation channel 32 under any circumstances are primarily supplied with pressure medium as in Figure 1. The second control device 70 can thus process two constant flows of different sizes and an increased pump delivery flow, with different pressure levels being possible as with the first control device.

As FIG. 3 shows in more detail, the first directional control valve can be used 11 the switching chambers 33 ', 3 ^' necessary to control the residual current in an advantageous manner between the pump chamber 23 'and the circulation chambers 29', 31 '. Since the first directional control valve 11 is only for a single-acting function, the second directional control valve 12 for

double-acting function must be designed, the first directional valve 11 is not much longer and can be accommodated with the second directional valve 12 in the same housing without further ado. The arrangement shown of the switching chambers '33', 3h ^r 'between the supply chamber 23' and the circulation chambers 29 ' , 31' also results in a relatively simple arrangement of the flow regulator 17 in the housing 15.

FIG. K shows part of a third control device 90 to which, as in FIG. 1, the remaining directional control valves 12 to 1 ^ with the end plate 16 are connected. The third control device 90, like the second control device 70 according to FIG. 2, should be able to process an increased input current to the directional control valve for the lifting function. The third control device 90 therefore differs from the first control device 10 according to FIG. 1 as follows, the same reference numerals being used for the same parts.

For the pressure medium supply is in addition to the first pump 18 a second pump 91 is provided, the output of which on the one hand via a third supply channel 92 with a pump safety check valve 93 with the inlet I9 connection and the other hand via a fourth supply channel 9 ^ · with the residual flow channel 35 between the flow regulator -and the first directional valve 11 is in connection.

The mode of operation of the third control device 90 differs from that of the first control device 10 essentially as follows: When the directional control valves 11 to 1 k are not actuated, the pressure medium flow, which is pumped depending on the speed, flows via the neutral circulation channel 32 back into the tank 21 from the second pump 91 conveyed pressure medium via the fourth

Supply channel 9U and the first directional control valve TI in its

Middle position ^ -3 to the drain channel 37 and also back to the tank 21. If the first directional control valve 11 is brought to the first working position kk for lifting, the second pump 91 conveys pressure medium via the third supply channel with the check valve 93 into the inlet 19 and the Common "delivery flow of both pumps 18, 91 flows through the inlet channel 25 to the consumer connection 28. For the lifting function a ^ veryrgrcSeörDruckmittelstrom is available. When a directional control valve 12 or 13 assigned to the constant flow is actuated, the flow regulator 17 leads the constant pressure medium flow into the supply line h6 " While the excess residual flow passes through the residual flow channel 35 and the non-actuated first directional valve 11 into the drainage channel 37 and on to the tank 21. If the first directional valve 11 is actuated simultaneously while the second directional valve 12 is actuated, the lifting function stands for the Residual flow of the first pump 18 as well as the too additional pressure medium flow of the second pumps 91 available. The fourth directional valve lh controls the entire amount of pressure medium of the first pump 18 when the associated rotating mechanism is actuated. In addition, with the third control device 90, the advantages of the first control device 1 can also be achieved.

Changes to the exemplary embodiments shown are of course also possible possible without deviating from the concept of the invention. Other compilations of the Directional control valves can be chosen to control devices without the advantageous arrangement of one of the overall or Directional valve assigned to residual current consumer spatially in front of a directional valve assigned to the constant current consumer to renounce. Standard directional control valves can also advantageously be used for supplementary functions be used. The constant current range of action in the control device can also be set in a simple manner

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change and adapt to the respective requirements. Of course, a boost inductor in the neutral circulation channel, also in the third control device according to FIG k be provided 32 to 18 to reach when needed independently of the speed of the "first pump a constant flow of pressure medium in Ueutralumlaufkanal 32nd Also, in the control apparatus of Figure 3 the current controller shown with the control member in full spool design readily be formed as a hollow spool. particularly advantageously, the specific type of pressure relief of the Weigenfunktion at a lower pressure level, which becomes effective only upon actuation of the second directional control valve 12 and also hj the control member is of the current controller 17 as Main control stage used for pressure limitation This type of secondary pressure limitation can also be used independently of the special requirements for the forklift valves shown in other applications.

Claims (1)

9/28/1981 My / Pi ROBERT BOSCH GMBH, 7000 Stuttgart 1 Expectations 1.) Hydraulic control device with at least two > ■ - • Directional control valves for controlling hydraulic consumers, in particular for a forklift truck, with one of one Pressure medium source guided via both directional control valves to the tank, in the middle position of the associated control slide open neutral circulation channel as well as with a current regulator connected in parallel to the neutral circulation channel, the constant flow of which is fed to the one directional control valve for the constant flow and its residual flow outlet is in connection with the other directional valve for the residual or total flow, characterized in that that the other directional control valve (11) for the total flow upstream is switched from a directional valve (12) for the constant current in the neutral circulation channel (32) that the residual _{flow line (35 S} 3T) is routed in a manner that is separate from and parallel to the neutral circulation channel (32) via the other directional valve (11) in a manner controllable by its control slide C4-2) and immediately after the other directional valve (11) to the tank (21 ) leads, and that the other directional control valve (11) has an inlet connection (23) connected to the pressure medium source (18) parallel to the neutral circulation channel (32). 2. Control device according to claim 1, characterized in that the current regulator (17) is a U-way current regulator, the constant current outlet (U5) with the one directional control valve (12, 13), the residual flow outlet (35) with the other directional control valve (11), whose first input (51) supplied via the flow regulator throttle (k8) with the pressure medium source (18) and its second input (52) parallel to the flow regulator throttle (hQ) with the pressure medium source (-18) are connected. 3. Control device according to claim 2, characterized in that the control member (lj-7) of the current regulator (17) of a spring (79) is loaded in the direction of an initial position in which there is the constant current passage (5.1 9 173 a opens and blocks the residual flow passage (52, 36), "with deflection from this position both passages (51, ^ -5; 52, 36) throttles and finally controls the latter in the opposite way in the end position. k " Control device according to one of claims 1 to 3, characterized in that the control element (^ T) of the flow regulator (17) serves as the main stage for a pilot-controlling pressure relief valve (5 ^ ₅ 55). (Figure 3). 5. Control device according to one of claims 1 to k, characterized in that the Druckmittelq.uelle consists of a single pump (18) "and in the neutral circulation channel (32) upstream of the branch (U9) to the flow controller (I7) and downstream of the branch (25) to the inlet connection (23) of the other directional control valve (11) is connected to an additional throttle (71) which controls the neutral circulation flow and whose pressure gradient can be effective at the control element (h "j) of the flow regulator (17) (Figure 2). 6. Control device according to one of claims 1 to 5, characterized in that the pressure medium source from there are two pumps (18, 91), of which the first (18) conveys into the neutral circulation channel (32) and the second * * ■ t - s. Pump (91) via a check valve that opens towards this (93) with the neutral circulation channel (32) and in parallel for this purpose in connection with the residual flow line (35 »37) between the flow regulator (17) and the other directional valve (11) stands. 7. Control device according to one of claims 1 to 6, characterized in that in the Ueutralumlaufkanal (32) downstream of one (12) and the other directional control valve (11) an additional directional control valve (1 h ) is connected, the inlet connection (23 ) is connected to the upstream section of the ITeutralumlauf s (32) to form a blocking circuit. 8. Control device according to one of claims 1 to J _3, characterized in that a directional control valve (12) associated with the second pressure relief valve (55) is provided, which pre-controls the control member (hj) of the flow regulator (17) and its outlet (56 ) a control line (hl) can be influenced via the control slide (^ 2) of the other directional control valve (11) and downstream of a directional control valve (12) in the neutral circulation channel (32). 9. Control device according to one of claims 7 and 8, characterized in that in the additional directional control valve (1 k ) a leading in the flange surface of the onward flow channel (46) is arranged, which is connected to the upstream portion of the neutral circulation channel (32). 10. Control device according to one of claims 1 to 9, characterized in that the other directional valve (11) is designed at least as a 7-way valve and corresponding to seven chambers (23 ', 26', 28 ' _s 33', 3 ¹ J- ' , 29 ', 31'), of which only one serves as a consumer chamber (28 ') and that the switching chambers (33', 3h ') assigned to the residual flow between the inlet chamber (23') and the circulation chambers (29 ^F , 31 ') ) are arranged. 11. Control device according to claim 10, characterized in that the control slide (^ 2) in addition to a central position (43) and a second working position (50), in each of which the Heutralumlaufkanal (32), the residual flow passage (33, 3 * 0 and in particular the control line (38, 39) are open, have a first working position (hk) in which the neutral circulation channel (32), the residual flow passage (33, 3 * 0 and in particular the control line (38, 39) are interrupted.