JP2007298055A - Apparatus for controlling hydraulic actuator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an apparatus for controlling a hydraulic actuator to be used in switching-over two hydraulic pumps to a combined flow state and a non-combined flow state, the apparatus which prevents the generation of shocks due to the switching. <P>SOLUTION: The apparatus for controlling the hydraulic actuator outputs a switching-over signal so as to switch a combined flow valve 10 to a connected state when the switching-over signal from an intercepted state to a connected state of the combined flow valve 10 is inputted, and after that, outputs a control operation signal corresponding to an operation signal from an operation means 21 to a control valve 8 by gradually changing the control operation signal from a first operation characteristic to a second operation characteristic, and also outputs a discharge oil volume control signal to a first variable displacement type hydraulic pump 2 and a second variable displacement type hydraulic pump 3 by gradually changing the discharge oil volume control signal from the first operation characteristic to the second operation characteristic. In addition, when the switching-over signal from the connected state to the intercepted state of the combined flow valve is inputted, the apparatus for controlling the hydraulic actuator outputs the discharge oil volume control signal to the first variable displacement type hydraulic pump 2 and the second variable displacement type hydraulic pump 3 by gradually changing the discharge oil volume control signal from the first operation characteristic to the second operation characteristic, and after the change into the first operation characteristic is finished, the switching-over signal is outputted so as to switch the combined valve 10 to the intercepted state. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a control device for a hydraulic actuator in a hydraulic working machine in which two hydraulic pumps are used by switching between merging and non-merging, and the speed of the hydraulic actuator is controlled by the discharge amount of the hydraulic pump. .

  An example of this type of hydraulic actuator control device is disclosed in Patent Document 1.

  The one disclosed in Patent Document 1 is controlled by two working hydraulic pumps, an electric operation lever, and an electromagnetic proportional pressure reducing valve for driving the spool of the control valve in response to an operation signal from the operation lever. A controller for outputting a signal and a switching valve for switching the two hydraulic pumps between a merging state and a non-merging state are provided to drive a plurality of hydraulic actuators.

Japanese Patent Publication No. 07-90290.

  By the way, in what was shown by this patent document 1, when this is considered as the circuit structure which each hydraulic pump drives one hydraulic actuator, respectively, and the rotation speed of a hydraulic pump is constant, for example, The control valve is set so as to be able to take in the maximum discharge oil amount when each hydraulic pump is in the merged state. For example, when each hydraulic pump is in the non-merged state, one hydraulic pressure is set. In the pump, the amount of discharged oil does not reach the maximum required flow rate (maximum intake flow rate) of the control valve. Therefore, if the control valve is switched between merging and non-merging in the latter half of the control valve spool stroke, the hydraulic actuator will The inflow rate of the water changes suddenly and a shock occurs.

  In addition, when the hydraulic pumps are joined, the pump outlet pressure and the load pressure signal necessary for the hydraulic pump capacity control are shared by the hydraulic pumps. Therefore, the capacity control of these two hydraulic pumps is performed. Therefore, if switching between merging and non-merging is performed during operation, the capacity of each hydraulic pump changes suddenly and a shock occurs.

  That is, a shock is generated both at the time of switching from a state where each hydraulic pump is not merged to a merged state and at the time of switching from a state where each hydraulic pump is merged to a non-merged state. There was a problem.

  Therefore, in the present invention, two hydraulic pumps are used to switch between merging and non-merging, and as a result, shocks at the time of switching between merging and non-merging are prevented as much as possible to improve operability. The object of the present invention is to provide a control device for a hydraulic actuator that can be realized.

  In the present invention, the following configuration is adopted as a specific means for solving such a problem.

  In the first invention of the present application, a first variable displacement hydraulic pump, a hydraulic actuator disposed corresponding to the first variable displacement hydraulic pump, the first variable displacement hydraulic pump, and the first hydraulic actuator. A control valve disposed between the control valve for driving and controlling the hydraulic actuator by supplying and discharging hydraulic pressure to the hydraulic actuator, an operation means for outputting an operation signal for operating the control valve, a second variable displacement hydraulic pump, , Disposed between a supply oil passage connecting the first variable displacement hydraulic pump and the control valve and a discharge oil passage of the second variable displacement hydraulic pump, and connecting the supply oil passage and the discharge oil passage or And a switching means for outputting a switching signal for switching the joining valve between a connected state and a shut-off state, and the control valve supplies an amount of oil supplied from the first variable displacement hydraulic pump. The total amount of oil supplied from the second variable displacement hydraulic pump is configured to be supplied to the hydraulic actuator, and the operation characteristics of the control operation of the hydraulic actuator by the control valve are as follows: The first operation characteristic in which the control operation is performed with the amount of oil supplied from the first variable displacement hydraulic pump, and the control operation is performed with the first variable displacement hydraulic pump and the second under the connected state of the switching means. And a second operating characteristic performed by the total amount of oil supplied from the variable displacement hydraulic pump, and when receiving a switching signal from the switching means to the shutoff state of the merging valve, based on the operation of the operating means A required oil amount required for driving the hydraulic actuator is calculated from the first operating characteristic, and a supply oil amount corresponding to the required oil amount is calculated as the first variable capacity. A discharge oil amount control signal is output to the first variable displacement hydraulic pump to be supplied from the hydraulic pump, and a control operation signal is output to the control valve to supply the required oil amount to the hydraulic actuator. When the switching signal to the connection state of the merging valve is received from the means, the required oil amount required to drive the hydraulic actuator based on the operation of the operating means is calculated from the second operating characteristic, Discharge oil to the first variable displacement hydraulic pump and the second variable displacement hydraulic pump to supply the supply oil amount corresponding to the required oil amount from the first variable displacement hydraulic pump and the second variable displacement hydraulic pump. A hydraulic actuator control device including a controller that outputs a volume control signal and outputs a control operation signal to the control valve to supply the required oil amount to the hydraulic actuator; In the first operating characteristic, the controller calculates the maximum amount of oil supplied from the first variable displacement hydraulic pump as the required oil amount during the maximum operation of the operating means, and in the second operating characteristic, The maximum total supply oil amount from the first variable displacement hydraulic pump and the second variable displacement hydraulic pump is calculated as a required oil amount during the maximum operation of the operation means. When a switching signal from the shut-off state to the connected state is received, a switching signal is output to bring the merging valve into the connected state, and then a control operation signal corresponding to the operation signal from the operating means is transmitted from the first operating characteristic to the above-mentioned While gradually changing to the second operating characteristic and outputting it to the control valve, the discharge oil amount control signal corresponding to the operating signal from the operating means is changed from the first operating characteristic to the second operating characteristic. The characteristics are gradually changed and output to the first variable displacement hydraulic pump and the second variable displacement hydraulic pump, and when the switching means receives a switching signal from the connection state of the junction valve to the cutoff state, The control operation signal corresponding to the operation signal from the operation means is gradually changed from the second operation characteristic to the first operation characteristic and output to the control valve, and the discharge oil corresponding to the operation signal from the operation means The amount control signal is gradually changed from the second operation characteristic to the first operation characteristic and output to the first variable displacement hydraulic pump and the second variable displacement hydraulic pump, and after the change to the first operation characteristic is completed. It is characterized in that a switching signal is output so as to put the merging valve in a shut-off state.

  In a second invention of the present application, a first variable displacement hydraulic pump, a first hydraulic actuator disposed corresponding to the first variable displacement hydraulic pump, the first variable displacement hydraulic pump, and the first A first control valve disposed between the hydraulic actuators for driving and controlling the first hydraulic actuator by supplying and discharging hydraulic pressure to the first hydraulic actuator, and a first signal for operating the first control valve. An operating means, a second variable displacement hydraulic pump, a second hydraulic actuator disposed corresponding to the second variable displacement hydraulic pump, and between the second variable displacement hydraulic pump and the second hydraulic actuator. And a second control valve that drives and controls the second hydraulic actuator by supplying and discharging hydraulic pressure to and from the second hydraulic actuator, and outputs an operation signal that operates the second control valve. Operated by the differential pressure between the operating means and the downstream hydraulic pressure which is arranged downstream of the first control valve and flows out of the first control valve and the pilot hydraulic pressure generated by slightly reducing the downstream hydraulic pressure. A first pressure compensation valve that controls the amount of oil supplied to the first hydraulic actuator, a downstream hydraulic pressure that is disposed downstream of the second control valve and flows out of the second control valve, and a slight amount of the downstream hydraulic pressure And a second pressure compensation valve that operates by a differential pressure with the pilot hydraulic pressure generated by reducing the pressure to the second hydraulic actuator to control the amount of oil supplied from the second control valve to the second hydraulic actuator. When the pilot oil passage and the pilot oil passage of the second pressure compensation valve are connected, the pilot pressure on the high pressure side is loaded on both the first pressure compensation valve and the second pressure compensation valve. Upstream of the first control valve; The differential pressure between the flow side and the differential pressure between the upstream side and the downstream side of the second control valve are made equal, and the flow rate ratio between the first control valve and the second control valve is set to the first operating means and the second operating means. Pressure compensation means corresponding to the required oil amount ratio set by the first variable displacement hydraulic pump, the first supply oil passage connecting the first variable displacement hydraulic pump and the first control valve, the second variable displacement hydraulic pump, and the above The first supply oil passage, the second supply oil passage, the pilot oil passage on the first pressure compensation valve side, and the second pressure compensation valve, which are arranged between the second supply oil passages connecting the second control valves. And a switching means for outputting a switching signal for switching the joining valve between a connected state and a shut-off state, wherein the first control valve is the first variable valve. The amount of oil supplied from the displacement hydraulic pump and the second variable displacement hydraulic pump The total oil amount of the supply oil amount can be supplied to the first hydraulic actuator, and the second control valve can supply the oil amount supplied from the first variable displacement hydraulic pump and the second variable displacement hydraulic pump. The total amount of oil supplied from the first hydraulic actuator can be supplied to the second hydraulic actuator, and the first control valve and the second control valve are operated in the control operation of the first hydraulic actuator and the second hydraulic actuator. As a characteristic, the control operation of the first hydraulic actuator by the first control valve is controlled by the amount of oil supplied from the first variable displacement hydraulic pump and the second control valve by the second control valve under the shutoff state of the merging valve. A first operating characteristic for performing a control operation of the hydraulic actuator with an amount of oil supplied from the second variable displacement hydraulic pump, and the first operating characteristic under the connection state of the merging valve. The control operation of the first hydraulic actuator by the control valve and the control operation of the second hydraulic actuator by the second control valve are supplied in total from the first variable displacement hydraulic pump and the second variable displacement hydraulic pump, respectively. In order to drive the first hydraulic actuator based on the operation of the first operating means when receiving a switching signal from the switching means to the shut-off state of the merging valve. Required oil amount is calculated from the first operating characteristic, and discharged oil is supplied to the first variable displacement hydraulic pump so that the supply oil amount corresponding to the required oil amount is supplied from the first variable displacement hydraulic pump. While outputting the amount control signal, the required amount of oil required to drive the second hydraulic actuator based on the operation of the second operating means is set to the first operating characteristic. A discharge oil amount control signal is output to the second variable displacement hydraulic pump so that the supply oil amount calculated from the second variable displacement hydraulic pump is supplied from the second variable displacement hydraulic pump. A control operation signal is output to the first control valve and the second control valve to be supplied to the first hydraulic actuator and the second hydraulic actuator, and a switching signal to the connection state of the merging valve is received from the switching means. Sometimes the required oil amount required to drive the first hydraulic actuator based on the operation of the first operating means and the second hydraulic actuator to be driven based on the operation of the second operating means The required required oil amount is calculated from the second operating characteristic, and the supply oil amount corresponding to the total required oil amount is supplied from the first variable displacement hydraulic pump and the second variable displacement hydraulic pump. In order to achieve this, a discharge oil amount control signal is output to the first variable displacement hydraulic pump and the second variable displacement hydraulic pump, and the required oil amount is supplied to the first hydraulic actuator and the second hydraulic actuator. In the hydraulic actuator control device including a controller that outputs a control signal to the first control valve and the second control valve, the controller has the first variable capacity during the maximum operation of the first operation means in the first operation characteristic. The maximum amount of oil supplied from the hydraulic pump is calculated as a required oil amount, and the maximum amount of oil supplied from the second variable displacement hydraulic pump is calculated as the required oil amount when the second operating means is operated maximum. In the second operating characteristic, the maximum total amount of oil supplied from the first variable displacement hydraulic pump and the second variable displacement hydraulic pump when the first operating means is maximum operated. The oil supply amount is calculated, and the maximum oil supply amount from the first variable displacement hydraulic pump and the second variable displacement hydraulic pump is calculated as the required oil amount at the maximum operation of the second operation means, When a switching signal from the shut-off state of the merging valve to the connected state is received from the switching means, a switching signal is output to bring the merging valve into a connected state, and then from the first operating means and the second operating means. A control operation signal corresponding to the operation signal is gradually changed from the first operation characteristic to the second operation characteristic and is output to the first control valve and the second control valve, and the first operation means and the second operation valve are output. The discharge oil amount control signal corresponding to the operation signal from the two operation means is gradually changed from the first operation characteristic to the second operation characteristic to thereby change the first variable displacement hydraulic pump and the second variable displacement hydraulic pressure. It to the pump And outputs a control operation signal corresponding to an operation signal from the first operation means and the second operation means when receiving a switching signal from the connection state to the cutoff state of the junction valve from the switching means. The discharge oil corresponding to the operation signals from the first operation means and the second operation means is outputted to the first control valve and the second control valve by gradually changing from the operation characteristics to the first operation characteristics. The amount control signal is gradually changed from the second operation characteristic to the first operation characteristic and is output to the first variable displacement hydraulic pump and the second variable displacement hydraulic pump, and the change to the first operation characteristic is completed. It is characterized in that a switching signal is outputted later to put the junction valve in a shut-off state.

  According to a third invention of the present application, in the hydraulic actuator control device according to the second invention, when the merging valve is in a connected state, it corresponds to an operation signal from the first operating means and the second operating means. The first variable displacement hydraulic pump and the second variable displacement hydraulic pump respectively bear approximately half of the total required oil amount of the first control valve and the second control valve as the supply oil amount. The discharge oil amount control signal is output to the first variable displacement hydraulic pump and the second variable displacement hydraulic pump.

  In the present invention, the following effects can be obtained.

(A) Hydraulic actuator control device according to the first invention of the present application (a-1) When a switching signal from the shutoff state of the junction valve to the connected state is received from the switching means, the junction valve is first set to the connected state. Therefore, after outputting the switching signal to the merging valve, the control operation signal corresponding to the operation signal from the operation means is gradually changed from the first operation characteristic to the second operation characteristic and is output to the control valve. The discharge oil amount control signal corresponding to the operation signal from the operation means is gradually changed from the first operation characteristic to the second operation characteristic to thereby change the first variable displacement hydraulic pump and the second variable displacement hydraulic pressure. Since the output to the pump is configured, the merging valve is connected, and the second variable displacement hydraulic pump is connected to the hydraulic actuator in addition to the amount of oil supplied from the first variable displacement hydraulic pump. Then, the operation characteristic of the control valve is gradually changed from the first operation characteristic to the second operation characteristic, and the first variable displacement hydraulic pump is The supply oil amount of the second variable displacement hydraulic pump is gradually changed from the supply oil amount corresponding to the first operation characteristic to the supply oil amount corresponding to the second operation characteristic. As a result, a sudden change in the amount of oil supplied to the hydraulic actuator is avoided, and the hydraulic actuator continues to operate smoothly with almost no shock.

  (A-2) When receiving a switching signal from the connection state of the junction valve to the cutoff state from the switching means, the control operation signal corresponding to the operation signal from the operation means is changed from the second operation characteristic to the first operation characteristic. And gradually changing the discharge oil amount control signal corresponding to the operation signal from the operation means from the second operation characteristic to the first operation characteristic. 1 and the second variable displacement hydraulic pump, and after the change to the first operating characteristic is completed, a switching signal is output to shut off the merging valve. Is gradually changed from the second operation characteristic to the first operation characteristic, and the supply oil amount of the first variable displacement hydraulic pump is changed from the supply oil amount corresponding to the second operation characteristic to the first operation characteristic. Oil supply corresponding to The gradual change is made, and then the merging valve is shut off. As a result, the difference in the amount of oil supplied to the hydraulic actuator before and after the switching of the merging valve state is eliminated as much as possible. The hydraulic actuator continues to operate smoothly with almost no shock.

  As described above, according to the control device for a hydraulic actuator according to the present invention, the occurrence of a shock at the time of switching the merging valve is prevented as much as possible, and its operability and operational reliability are improved.

(B) a hydraulic actuator control apparatus according to the second invention of the present application;
(B-1) When the switching signal from the shutoff state of the junction valve to the connected state is received from the first switching means, first, a switching signal is output to the junction valve so that the junction valve is in the connected state, and then the first A control operation signal corresponding to an operation signal from the operation means and the second operation means is gradually changed from the first operation characteristic to the second operation characteristic and output to the first control valve and the second control valve, and The discharge oil amount control signal corresponding to the operation signals from the first operation means and the second operation means is gradually changed from the first operation characteristic to the second operation characteristic to change the first variable displacement hydraulic pump. Since it is configured to output to the second variable displacement hydraulic pump, the merging valve is connected, and the first variable displacement hydraulic pump and the first hydraulic pump are connected to the first hydraulic actuator and the second hydraulic actuator. 2 variable volume After entering the state in which hydraulic pressure can be supplied from both of the quantity type hydraulic pumps, the operation characteristics of the first control valve and the second control valve are gradually changed from the first operation characteristic to the second operation characteristic. The supply oil amount of the first variable displacement hydraulic pump and the second variable displacement hydraulic pump is gradually changed from the supply oil amount corresponding to the first operation characteristic to the supply oil amount corresponding to the second operation characteristic. Will be. As a result, sudden changes in the amount of oil supplied to the first hydraulic actuator and the second hydraulic actuator are avoided, and the first hydraulic actuator and the second hydraulic actuator continue to operate smoothly with almost no shock. .

  (B-2) When a switching signal from the connection state of the junction valve to the cutoff state is received from the switching means, a control operation signal corresponding to the operation signals from the first operation means and the second operation means is sent to the second operation means. The discharge oil amount corresponding to the operation signals from the first operation means and the second operation means while gradually changing from the operation characteristics to the first operation characteristics and outputting them to the first control valve and the second control valve. The control signal is gradually changed from the second operation characteristic to the first operation characteristic and output to the first variable displacement hydraulic pump and the second variable displacement hydraulic pump, and after the change to the first operation characteristic is completed, the control signal is output. Since the switching signal is output so that the junction valve is shut off, first, the operating characteristics of the first and second control valves are gradually changed from the second operating characteristics to the first operating characteristics. And the first variable volume The supply oil amount of the hydraulic pump and the second variable displacement hydraulic pump is gradually changed from the supply oil amount corresponding to the second operation characteristic to the supply oil amount corresponding to the first operation characteristic, and then the merging The valve is shut off. As a result, the difference in the amount of oil supplied to the first hydraulic actuator and the second hydraulic actuator before and after the switching of the state of the merging valve disappears as much as possible, and the first hydraulic actuator and the second hydraulic actuator are almost shocked. The operation will continue smoothly without occurring.

  Thus, according to the control device for a hydraulic actuator according to the second aspect of the present invention, the occurrence of a shock at the time of switching the merging valve is prevented as much as possible, and its operability and operational reliability are improved. It is.

  (C) According to the hydraulic actuator control device of the third invention of the present application, in addition to the effect described in the above (b), the following specific effect can be obtained. That is, according to the present invention, when the merging valve is in the connected state, the sum of the first control valve and the second control valve corresponding to the operation signals from the first operation means and the second operation means. The first variable displacement hydraulic pump and the second variable displacement type are arranged so that approximately half of the required oil amount is borne by the first variable displacement hydraulic pump and the second variable displacement hydraulic pump, respectively. Since the discharge oil amount control signal is output to the hydraulic pump, for example, the first variable displacement hydraulic pump and the above corresponding to the operation signals from the first operating means and the second operating means. Compared with the configuration for controlling the discharge oil amount of the second variable displacement hydraulic pump, the pump displacement control in the controller is extremely simple, and the cost can be reduced by simplifying the control system.

  Further, for example, when the first operating characteristic is set to ½ of the second operating characteristic, the merging is performed under the condition that only one hydraulic actuator is operated in the first invention and the second invention. It is only necessary to change the pump characteristics of the variable displacement hydraulic pump on the incoming side, and the operation characteristics can be easily changed.

  Hereinafter, the present invention will be specifically described based on preferred embodiments.

  FIG. 1 shows a hydraulic circuit of a hydraulic working machine according to an embodiment of the present invention and a control system thereof, and FIGS. 2 and 3 show enlarged main parts of FIG. Reference numeral 5 denotes a first hydraulic actuator composed of a hydraulic motor for rotationally driving the winch 7, and reference numeral 6 denotes a second hydraulic actuator composed of a hydraulic cylinder. The first hydraulic actuator 5 and the second hydraulic actuator 6 are connected to this hydraulic actuator. It becomes the main subject of the hydraulic working machine. In order to control the operation of the first hydraulic actuator 5 and the second hydraulic actuator 6, the hydraulic pressure supply unit X described below and the hydraulic actuators 5, 6 receive hydraulic pressure from the hydraulic pressure supply unit X. And a control unit Z that controls the hydraulic pressure supply unit X and the operation control unit Y in response to an operator's operation.

I: Hydraulic supply part X
As shown in FIGS. 1 and 2, the hydraulic pressure supply unit X includes an engine 1 as a driving source, a first variable displacement hydraulic pump 2 and a second variable displacement hydraulic pump for work driven by the engine 1. 3 and a hydraulic pump 4 for generating pilot pressure.

  Both the first variable displacement hydraulic pump 2 and the second variable displacement hydraulic pump 3 receive the discharge amount control signal from the controller 20 of the control unit Z described later (that is, the first control valve 8 and the later described). The amount of oil supplied to the second control valve 9 side is controlled to increase or decrease. This displacement control will be described below for the first variable displacement hydraulic pump 2 side.

  That is, a control cylinder 25 is attached to the first variable displacement hydraulic pump 2, and a control spool 27 is attached to the rod end of the control cylinder 25 via a compression spring 44. Further, the control spool 27 is provided with a control piston 29, and the control spool 27 is driven by the spring 45 in the direction of compressing the spring 44 via the control piston 29. Yes. A pilot pressure is applied to the reduction side of the control piston 29 via an electromagnetic proportional pressure reducing valve 18 that operates in response to a discharge amount control signal from the controller 20.

  Further, on the extension side of the control cylinder 25, the discharge pressure of the first variable displacement hydraulic pump 2 and the pilot pressure from the hydraulic pump 4 are selected by the shuttle valve 46 via the control spool 27. The pilot pressure on the high pressure side is introduced, while the discharge pressure of the first variable displacement hydraulic pump 2 is introduced as the pilot pressure on the reduction side.

  Here, the displacement control of the first variable displacement hydraulic pump 2 will be specifically described.

  When no discharge amount control signal is input to the electromagnetic proportional pressure reducing valve 18, pilot pressure does not act on the control piston 29, so that the control piston 29 is fully extended by the spring 45 and receives it. The control spool 27 is set to the first valve position 27A, the pilot pressure from the shuttle valve 46 is introduced to the extension side of the control cylinder 25 through the control spool 27, and the control cylinder 25 is fully The capacity of the first variable displacement hydraulic pump 2 is set to “0”.

  On the other hand, when a discharge amount control signal is input to the electromagnetic proportional pressure reducing valve 18, the pilot pressure of the control piston 29 acts, and the control piston 29 is pulled back to a position corresponding to the pilot pressure. Then, the control spool 27 is pushed back from the first valve position 27A to the second valve position 27B by the spring 44, the pilot pressure is released from the extending side of the control cylinder 25, and the control cylinder 25 is contracted.

  At this time, one end side of the control spool 27 is biased from the control cylinder 25 side via the spring 44, and the other end side is proportional to the spring force by the spring 45 and the proportional valve via the control piston 29. The control spool 27 is biased by the difference in the pullback force of the control piston 29 due to the pilot pressure from 18, so that the control spool 27 stops at a position where both pilot pressures are balanced during the switching, thereby the first The capacity of the variable displacement hydraulic pump 2 is determined. That is, the capacity of the first variable displacement hydraulic pump 2 is increased or decreased in response to the discharge amount control signal input to the electromagnetic proportional pressure reducing valve 18.

  In addition, about the said 2nd variable displacement hydraulic pump 3 side, the said description about the said 1st variable displacement hydraulic pump 2 side is used.

II: Operation control unit Y
The operation control unit Y includes a first control valve 8, a second control valve 9, and a merging valve 10 described below.

II-1: Configuration of the First Control Valve 8 The first control valve 8 is configured by a 7-port 3-position pilot type switching valve, and the first hydraulic actuator 5 is supplied and discharged to and from the first hydraulic actuator 5. The first port 8a is connected to the first supply oil passage 31 extending from the discharge port of the first variable displacement hydraulic pump 2, and the second port 8b and the second port 8b are connected to the first port 8a. The three ports 8c are connected to the first hydraulic actuator 5 via an oil passage 33 and an oil passage 34, respectively.

  The fourth port 8d of the first control valve 8 is connected to a first port 11a of the first pressure compensation valve 11 described later, and the fourth port 8e and the fifth port 8f are both third ports of the first pressure compensation valve 11. It is connected to the port 11c. The first port 8a and the fourth port 8d are connected via the opening area of the spool at both the first valve position 8A and the second valve position 8B of the first control valve 8.

  A pilot pressure is applied to both ends of the spool of the first control valve 8 via an electromagnetic proportional pressure reducing valve 13 and an electromagnetic proportional pressure reducing valve 14, respectively. The spool is displaced, and the first supply oil passage 31 is selectively connected to the oil passage 33 and the oil passage 34, whereby the hydraulic pressure is supplied to and discharged from the first hydraulic actuator 5, and the spool The amount of oil supplied to the first hydraulic actuator 5 side is increased or decreased by changing the oil passage area corresponding to the stroke change, and the operating speed of the first hydraulic actuator 5 is thereby controlled.

  The first pressure compensating valve 11 is a three-port three-position pilot type switching valve, the first port 11a is connected to the fourth port 8d of the first control valve 8, and the second port 11b is a pilot oil passage. The third port 11c is connected to the fourth port 8e and the fifth port 8f of the first control valve 8. The first port 11a and the third port 11c of the first pressure compensation valve 11 are connected in a throttled state, and the first port 11a and the second port are connected at the second valve position 11B. 11b is connected through a diaphragm. Further, the hydraulic pressure from the fourth port 8d of the first control valve 8 is directly used as a pilot pressure at one end of the spool of the first pressure compensation valve 11, and the fourth port 8d of the first control valve 8 is provided at the other end. The oil pressure from the engine is slightly reduced to act as the pilot pressure.

  The electromagnetic proportional pressure reducing valve 13 and the electromagnetic proportional pressure reducing valve 14 are controlled by a control operation signal from a controller 20 described later.

II-2: Configuration of second control valve 9 and the like The second control valve 9 is a second control valve configured by a 7-port three-position pilot type switching valve, similar to the first control valve 8, The operation of the second hydraulic actuator 6 is controlled by supplying and discharging the hydraulic pressure to the second hydraulic actuator 6. The second port extending from the discharge port of the second variable displacement hydraulic pump 3 to the first port 9a. The supply oil passage 32 is connected, and the second port 9b and the third port 9c are connected to the second hydraulic actuator 6 through an oil passage 35 and an oil passage 36, respectively.

  The fourth port 9d of the second control valve 9 is connected to a first port 12a of a second pressure compensation valve 12, which will be described later, and the fourth port 9e and the fifth port 9f are both the third port of the second pressure compensation valve 12. It is connected to the port 12c. The first port 9a and the fourth port 9d are connected via a spool opening area in both the first valve position 9A and the second valve position 9B of the second control valve 9.

  A pilot pressure is applied to both ends of the spool of the second control valve 9 via an electromagnetic proportional pressure reducing valve 15 and an electromagnetic proportional pressure reducing valve 16, respectively. The spool is displaced, and the second supply oil passage 32 is selectively connected to the oil passage 35 and the oil passage 36, whereby the hydraulic pressure is supplied to and discharged from the second hydraulic actuator 6, and the spool As the oil passage area changes in response to the change in stroke, the amount of oil supplied to the second hydraulic actuator 6 is increased or decreased, and the operating speed of the second hydraulic actuator 6 is controlled.

  The second pressure compensation valve 12 is a three-port three-position pilot type switching valve, the first port 12a is connected to the fourth port 9d of the second control valve 9, and the second port 12b is a pilot oil passage. The third port 12c is connected to the fourth port 9e and the fifth port 9f of the second control valve 9. The first pressure position 12A of the second pressure compensation valve 12 is connected in a state where the first port 12a and the third port 12c are throttled, and the first port 12a and the second port are connected at the second valve position 12B. 12b is connected through a diaphragm. Further, the hydraulic pressure from the fourth port 9d of the second control valve 9 is directly used as a pilot pressure at one end of the spool of the second pressure compensation valve 12, and the fourth port 9d of the second control valve 9 is provided at the other end. The oil pressure from the engine is slightly reduced to act as the pilot pressure.

  The electromagnetic proportional pressure reducing valve 15 and the electromagnetic proportional pressure reducing valve 16 are controlled to operate according to a control operation signal from a controller 20 described later.

II-3: Configuration of Merge Valve 10 The merge valve 10 includes an intermediate position of a connection oil passage 37 connecting the first supply oil passage 31 and the second supply oil passage 32, and the first pressure compensation valve 11. And the intermediate position of the pilot oil passage 38 connecting the second pressure compensation valve 12, and the connection oil passage 37 and the pilot oil passage 38 are simultaneously switched between a connected state and a shut-off state.

  This merging valve 10 is constituted by a four-port two-position switching valve, and is switched when a pilot pressure supplied from the hydraulic pump 4 is loaded by the electromagnetic switching valve 17, and the connection is made at the first valve position 10A. The oil passage 37 and the pilot oil passage 38 are both shut off, and the connection oil passage 37 and the pilot oil passage 38 are connected together at the second valve position 10B. The electromagnetic switching valve 17 is controlled by a switching signal from a controller 20 described later.

II-4: Functions of the first pressure compensation valve 11 and the second pressure compensation valve 12 The first pressure compensation valve 11 and the second pressure compensation valve 12 (both of which constitute the “pressure compensation means” in the claims) Are combined to form a flow dividing function according to the ratio of the opening areas of the first control valve 8 and the second control valve 9 under the connected state of the merging valve 10.

  That is, when both the first control valve 8 and the second control valve 9 are operated in a state where the connection oil passage 37 and the pilot oil passage 38 are connected together by the merging valve 10, the first pressure On the compensation valve 11 side, the first hydraulic pressure of the first pressure compensation valve 11 is changed with the combined hydraulic pressure of the first variable displacement hydraulic pump 2 and the second variable displacement hydraulic pump 3 through the first control valve 8. It acts as a pilot pressure on the spool end on the two-valve position 11B side. Further, a hydraulic pressure obtained by further reducing the pilot pressure acts as a pilot pressure on the spool end of the first pressure compensation valve 11 on the first valve position 11A side. When the hydraulic pressure flows from the first control valve 8 to the first pressure compensation valve 11 side, the pilot pressure acting on the second valve position 11B side is applied to the first pressure compensation valve 11 so that the pilot pressure acts on the first valve position 11A. Since the pressure is higher than the pilot pressure acting on the side, the second valve position 11B is set by the differential pressure between the two pilot pressures, and the hydraulic pressure from the first control valve 8 is the second pressure of the first pressure compensation valve 11. The gas is again supplied from the 3 port 11c through the first control valve 8 to the first hydraulic actuator 5 side. Such an operation is the same on the second pressure compensation valve 12 side, and the explanation here is omitted by using the explanation on the first pressure compensation valve 11 side.

  Here, if there is no difference between the operating load of the first hydraulic actuator 5 and the operating load of the second hydraulic actuator 6, the pilot pressure acting on the first valve position 11A side of the first pressure compensating valve 11 The pilot pressure acting on the first valve position 12A side of the second pressure compensating valve 12 becomes the same, and the differential pressure between the upstream side and the downstream side of the first control valve 8 and the upstream side of the second control valve 9 are the same. The differential pressure between the side and the downstream side is also the same, and each of these control valves 8 and 9 supplies a hydraulic pressure corresponding to each valve stroke (ie, required oil amount). That is, since the flow rate ratio between the first control valve 8 and the second control valve 9 matches the required oil amount ratio between the first control valve 8 and the second control valve 9, no problem occurs.

  However, if a difference occurs between the operating load of the first hydraulic actuator 5 and the operating load of the second hydraulic actuator 6, normally, the hydraulic pressure is preferentially supplied to the side where the load is small, and the side where the load is large Insufficient oil amount occurs. That is, there is a difference between the correspondence relationship between the flow rate ratio and the required oil amount ratio in the first control valve 8 and the correspondence relationship between the flow rate ratio and the required oil amount ratio in the second control valve 9.

  However, according to this embodiment, when there is a difference between the operation load of the first hydraulic actuator 5 and the operation load of the second hydraulic actuator 6, the difference between the loads is the first pressure compensation valve 11. Between the pilot pressure acting on the first valve position 11A side and the pilot pressure acting on the first valve position 12A side of the second pressure compensating valve 12, and in this case, the first pressure compensating valve 11 Since the pilot pressure path on the side and the pilot pressure path on the second pressure compensation valve 12 side are connected via the pilot oil path 38, the pilot pressure on the high pressure side of these pilot pressures is the first pressure. It acts on both the compensation valve 11 and the second pressure compensation valve 12. For example, when it is assumed that the operating load on the first control valve 8 side is lower than that on the second control valve 9 side, the first pressure compensation valve 11 side acts on the first valve position 11A side. The spool is pushed back by the increase of the pilot pressure and moves from the second valve position 11B side to the first valve position 11A side. By the throttle action at the first valve position 11A, the upstream side and the downstream side on the first control valve 8 side. The differential pressure between the two sides and the differential pressure between the upstream side and the downstream side on the second control valve 9 side are equalized. As a result, even if a difference occurs in the operating load between the hydraulic actuators 5 and 6, the relationship between the flow rate ratio and the required oil amount ratio in the first control valve 8 is not affected by this. The correspondence relationship between the flow rate ratio and the required oil amount ratio in the second control valve 9 is matched, and the oil amount is distributed to the first hydraulic actuator 5 and the second hydraulic actuator 6 at a ratio corresponding to each required oil amount ratio. Is something that can be done.

II-5: Operation characteristics of the first control valve 8 and the second control valve 9 As described above, the first control valve 8 and the second control valve 9 are each provided with a pair of electromagnetic proportional pressure reducing valves 13, 14, 15 and 16 are actuated by receiving a control operation signal from the controller 20, and are switched by applying a required pilot pressure to the spool, and the opening corresponding to the magnitude of the control operation signal. The area is controlled. In this embodiment, as described above, the first supply oil passage 31 on the first variable displacement hydraulic pump 2 side and the second supply oil passage on the second variable displacement hydraulic pump 3 side by the merging valve 10 as described above. 32 is switched between a cut-off state and a connection state.

  That is, in the shut-off state by the merging valve 10, the first hydraulic actuator 5 is the amount of oil supplied from the first variable displacement hydraulic pump 2, and the second hydraulic actuator 6 is the second variable displacement hydraulic pump 3. The amount of oil supplied from each is individually operated. On the other hand, in the connected state by the merging valve 10, both the first hydraulic actuator 5 and the second hydraulic actuator 6 are connected to the first variable displacement hydraulic pump 2 and the second variable displacement hydraulic pump 3. Is operated by the total oil supply from

  Therefore, in the connected state, the first control valve 8 and the second control valve 9 include the first control valve 8 that supplies the amount of oil supplied from the first variable displacement hydraulic pump 2 and the second variable displacement type. Since there is a possibility that the total amount of oil supplied from the hydraulic pump 3 may flow, the first control valve 8 is supplied with the amount of oil supplied from the first variable displacement hydraulic pump 2 and the second variable displacement hydraulic pump. The second control valve 9 is configured so that the total amount of oil supplied from 3 can be supplied to the first hydraulic actuator 5, and the second control valve 9 supplies the amount of oil supplied from the first variable displacement hydraulic pump 2 and the second variable displacement type. The total amount of oil supplied from the hydraulic pump 3 is set so that it can be supplied to the second hydraulic actuator 6. That is, in FIG. 4, when the valve stroke is 100%, the supply oil amount from the first variable displacement hydraulic pump 2 and the maximum total supply oil amount “Qa1” from the second variable displacement hydraulic pump 3 are received. Be able to.

  On the other hand, in the shut-off state, it is sufficient that the first control valve 8 can accept the maximum amount of oil supplied from the first variable displacement hydraulic pump 2, and the second control valve 9 is sufficient for the second variable displacement. It is sufficient to be able to accept the maximum amount of oil supplied from the hydraulic pump 3. That is, in FIG. 4, it is sufficient if [Qa1 / 2] = “Qa2” can be accepted.

  Therefore, in this embodiment, the valve strokes of the first control valve 8 and the second control valve 9 are within the range of 0 to 100% opening area (required oil amount) in the connected state, and the shut-off state. Then, it is set in the range of 0 to 50% opening area (required oil amount).

FIG. 5 shows this setting in relation to the operation amount of the operation lever and the required valve flow rate in each of the connection state and the cutoff state of the merging valve 10. That is, in the figure, the curve L1 indicates the characteristic in the connected state, and the curve L2 indicates the characteristic in the cutoff state. In the connected state, the required flow rate of “Qb1 (= Qa1)” can be obtained when the operating lever is operated 100%, but in the disconnected state, even if the operating lever is operated 100%, “Qb2 (= Qa2 =“ Only the required flow rate of Qb1 "/ 2)" is obtained.
III: Control unit Z
As shown in FIG. 1, the control unit Z includes a controller 20, a first operation unit 21 and a second operation unit 22 that output an operation signal to the controller 20.

  The first operating means 21 includes an operating lever 40 that is operated by an operator to operate the first hydraulic actuator 5 through the operation of the first control valve 8. The second operation means 22 includes an operation lever 41 that is operated by an operator so as to operate the second hydraulic actuator 6 through operation of the second control valve 9. The first operation means 21 and the second operation means 22 output an operation signal having a magnitude corresponding to the operation amount of the operation lever 40 and the operation lever 41 to the controller 20.

  The controller 20 receives operation signals from the first operation means 21 and the second operation means 22, and the electromagnetic proportional pressure reducing valve 13 and the electromagnetic proportional pressure reducing valve 14 attached to the first control valve 8, and the above A setting operation signal is output to the electromagnetic proportional pressure reducing valve 15 and the electromagnetic proportional pressure reducing valve 16 attached to the second control valve 9 to control the operations of the first control valve 8 and the second control valve 9. The controller 20 receives operation signals from the first operation means 21 and the second operation means 22 and outputs a discharge amount control signal to each of the electromagnetic proportional pressure reducing valves 18 and 19 of the hydraulic pressure supply unit X. Thus, the displacement (supply oil amount) of the first variable displacement hydraulic pump 2 and the second variable displacement hydraulic pump 3 is controlled, and a switching signal from the switching means 24 is sent to the merging valve 10. Output to the switching valve 17 to connect or shut off the merging valve 10. In this embodiment, the switching means 24 is configured to be manually operated by an operator.

  The controller 20 has an operation characteristic 23 in the control operation of the hydraulic actuators 5 and 6 by the control valves 8 and 9. That is, in this embodiment, the following first operation characteristic and second operation characteristic are set as the operation characteristics.

  The first operating characteristic is an operating characteristic when the merging valve 10 is set in a shut-off state, and the control operation of the first hydraulic actuator 5 by the first control valve 8 is controlled by the first variable displacement hydraulic pump 2. The operation characteristic is that the control operation of the second hydraulic actuator 6 by the second control valve 9 is performed by the amount of oil supplied from the second variable displacement hydraulic pump 3.

  The second operating characteristic is an operating characteristic when the merging valve 10 is set to a connected state, and is a control operation of the first hydraulic actuator 5 by the first control valve 8 and the second operation characteristic by the second control valve 9. 2 is an operation characteristic in which the control operation of the hydraulic actuator 6 is performed with the total amount of oil supplied from the first variable displacement hydraulic pump 2 and the second variable displacement hydraulic pump 3, respectively.

  The controller 20 receives the operation signals from the operation means 21 and 22 and receives the operation signals from the operation means 21 and 22 so as to select either the first operation characteristic or the second operation characteristic. Control operation signals are output to the valves 13 and 14 and the electromagnetic proportional pressure reducing valves 15 and 16 on the second control valve 9 side.

  Here, the contents of each control in relation to the operation characteristics in the controller 20 will be specifically described.

  First, the amount of oil supplied to each of the variable displacement hydraulic pumps 2 and 3 is calculated. In this embodiment, the present invention is applied as follows.

  (A-1) In the first operating characteristic, the maximum amount of oil supplied from the first variable displacement hydraulic pump 2 is calculated as the required oil amount when the first operating means 21 is operated maximum. The maximum amount of oil supplied from the second variable displacement hydraulic pump 3 is calculated as the required oil amount when the two operating means 22 are operated maximum.

  (A-2) In the second operation characteristic, the maximum total supply oil amount from the first variable displacement hydraulic pump 2 and the second variable displacement hydraulic pump 3 is requested at the maximum operation of the first operation means 21. The amount of oil is calculated, and the maximum amount of oil supplied from the first variable displacement hydraulic pump 2 and the second variable displacement hydraulic pump 3 is calculated as the required oil amount when the second operation means 22 is operated maximum.

Next, the operation control of the control valves 8 and 9 and the variable displacement hydraulic pumps 2 and 3 corresponding to the switching state of the merging valve 10 will be described.
(B-1) When a switching signal from the shut-off state of the merging valve 10 to the connected state is received In this case, first, a switching signal is output to bring the merging valve 10 into the connected state, and the 10 is connected. State. Thereafter, the control operation signal corresponding to the operation signals from the first operation means 21 and the second operation means 22 is gradually changed from the first operation characteristic to the second operation characteristic, and the first control valve and While being output to the second control valve, the discharge oil amount control signal corresponding to the operation signals from the first operation means and the second operation means is gradually changed from the first operation characteristic to the second operation characteristic. And output to the first variable displacement hydraulic pump 2 and the second variable displacement hydraulic pump 3, respectively.

(B-2) When a switching signal from the connected state of the merging valve 10 to the shut-off state is received In this case, first, it corresponds to the operation signals from the first operating means 21 and the second operating means 22. The control operation signal is gradually changed from the second operation characteristic to the first operation characteristic and output to the first control valve 8 and the second control valve 9, and the first operation means and 21 and the second operation characteristic are output. By gradually changing the discharge oil amount control signal corresponding to the operation signal from the means 22 from the second operation characteristic to the first operation characteristic, the first variable displacement hydraulic pump 2 and the second variable displacement hydraulic pressure are changed. Output to pump 3. Then, after the change to the first operating characteristic is completed, a switching signal is outputted to put the merging valve 10 in a shut-off state, and this is put into a shut-off state.

IV: Explanation of an operation example IV-1: At the time of the operation | work which sets the said merging valve 10 to the interruption | blocking state In this case, the control corresponding to the operation signal from the said 1st operation means 21 and the said 2nd operation means In response to the operation signals, the first control valve 8 and the second control valve 9 are operated, and the hydraulic pressure is supplied to and discharged from the first hydraulic actuator 5 and the second hydraulic actuator 6.

  That is, the control operations of the first hydraulic actuator 5 and the second hydraulic actuator 6 by the first control valve 8 and the second control valve 9 are both performed under the first operating characteristic, and the first hydraulic actuator 5 Is supplied with the amount of oil supplied from the first variable displacement hydraulic pump 2, and the second hydraulic actuator 6 is supplied with the amount of oil supplied from the second variable displacement hydraulic pump 3. The first variable displacement hydraulic pump 2 receives the discharge oil amount control signal corresponding to the operation signal from the first operation means 21 from the controller 20 to the electromagnetic proportional pressure reducing valve 18. The oil amount corresponding to the discharge oil amount control signal is discharged. The second variable displacement hydraulic pump 3 receives the discharge oil amount control signal corresponding to the operation signal from the second operation means 22 from the controller 20 to the electromagnetic proportional pressure reducing valve 19. The oil amount corresponding to the discharge oil amount control signal is discharged.

  In the first operating characteristic, when the first operating means 21 is operated to the maximum on the first operating means 21 side, the maximum supply oil amount is calculated as the required oil amount by the first variable displacement hydraulic pump 2. On the second operation means 22 side, when the second operation means 22 is operated to the maximum, the second variable displacement hydraulic pump 3 calculates the maximum supply oil amount as the required oil amount.

  Accordingly, the required oil amount corresponding to the operation signal from the first operation means 21 always corresponds to the amount of oil supplied from the first variable displacement hydraulic pump 5, and the operation signal from the second operation means 22. And the amount of oil supplied from the second variable displacement hydraulic pump 6 correspond to each other. For example, the first operating means 21 and the second operating means 22 are in the maximum operating state (100% operation), respectively. The maximum amount of oil supplied from the first variable displacement hydraulic pump 2 and the second variable displacement hydraulic pump 3 to the first hydraulic actuator 5 and the second hydraulic actuator 6, respectively. When the first operating means 21 and the second operating means 22 are in a half-operating state (50% operating state), respectively, the first hydraulic actuator 5 and the second hydraulic actuator 6 Then, an oil amount that is half of the maximum oil supply amount is supplied to the first hydraulic actuator 5 and the second hydraulic actuator 6, and in each of the first control valve 8 and the second control valve 9, the entire range of valve strokes is obtained. The hydraulic supply without excess or deficiency is realized.

IV-2: During work with the merging valve 10 set to the connected state In this case, the control operation signals corresponding to the operation signals from the first operation means 21 and the second operation means 22 are received respectively. The first control valve 8 and the second control valve 9 are actuated, and the hydraulic pressure is supplied to and discharged from the first hydraulic actuator 5 and the second hydraulic actuator 6. That is, the control operations of the first hydraulic actuator 5 and the second hydraulic actuator 6 by the first control valve 8 and the second control valve 9 are both under the second operating characteristic, and the first hydraulic actuator 5 and the second hydraulic actuator 6 are controlled. This is performed by supplying the total amount of oil supplied from the first variable displacement hydraulic pump 2 and the second variable displacement hydraulic pump 3 to the two hydraulic actuator 6. The first variable displacement hydraulic pump 2 and the second variable displacement hydraulic pump 3 have discharge oil amount control signals corresponding to the operation signals from the first operation means 21 and the second operation means 22, respectively. When the controller 20 inputs the electromagnetic proportional pressure reducing valve 18 and the electromagnetic proportional pressure reducing valve 19 respectively, the oil amount corresponding to each discharge oil amount control signal is discharged, and each of these variable displacement hydraulic pumps 2 is discharged. , 3 is supplied to the first hydraulic actuator 5 and the second hydraulic actuator 6.

  In the second operation characteristic, the maximum total supply oil amount from the first variable displacement hydraulic pump 2 and the second variable displacement hydraulic pump 3 when the first operation means 21 is maximum operated is used as the required oil amount. The maximum total supply oil amount from the first variable displacement hydraulic pump 2 and the second variable displacement hydraulic pump 3 is calculated as the required oil amount when the second operation means 22 is operated maximum. .

  Accordingly, the required amount of oil corresponding to the operation signals from the first operation means 21 and the second operation means 22 is always the sum from the first variable displacement hydraulic pump 2 and the second variable displacement hydraulic pump 3. For example, when the first control means 21 is in a maximum operation state (100% operation state), the maximum amount of oil supplied from the first variable displacement hydraulic pump 2 and the second variable displacement hydraulic pump 3 is When the total supply oil amount is supplied as it is and the first control means 21 is in a half operation state (50% operation state), the first variable displacement hydraulic pump 2 and the second variable displacement hydraulic pump 3 An oil amount that is half of the maximum total supply oil amount is supplied, and hydraulic supply without excess or deficiency is realized in the entire operation region of the first control means 21.

  Similarly, when the second control means 22 is in the maximum operation state (100% operation state), the maximum total supply oil amount from the first variable displacement hydraulic pump 2 and the second variable displacement hydraulic pump 3. Is supplied as it is, and when the second control means 22 is in a half-operation state (50% operation state), the maximum total supply from the first variable displacement hydraulic pump 2 and the second variable displacement hydraulic pump 3 The oil amount that is half of the oil amount is supplied, and the hydraulic pressure supply without excess or deficiency is realized in the entire operation region of the second control means.

  In this way, when the first operating means 21 and the second operating means 22 are individually operated, the first pressure compensating valve 11 and the second pressure compensating valve 12 do not exhibit any effective function. In addition, there may be a state in which only one of the first operating means 21 and the second operating means 22 is operated and the other is not operated, but the control in such a state is related to claim 1 of the present application. It falls under the invention. Therefore, description of embodiment of the invention which concerns on Claim 1 uses this description, and description here is abbreviate | omitted.

  On the other hand, when the first operating means 21 and the second control means 22 are operated simultaneously, the first pressure compensating valve 11 and the second pressure compensating valve 12 function effectively.

  That is, when the first operating means 21 and the second control means 22 are operated simultaneously, for example, when both are in the maximum operating state (100% operating state), the first variable displacement hydraulic pump 2 and the second variable displacement type are operated. The maximum total supply oil amount is supplied from the hydraulic pump 3, but under the second operating characteristic, the first variable displacement hydraulic pump 2 and the second variable displacement type when the first operating means 21 is operated maximum. The maximum total supply oil amount from the hydraulic pump 3 is calculated as the required oil amount, and the maximum from the first variable displacement hydraulic pump 2 and the second variable displacement hydraulic pump 3 when the second operation means 22 is maximum operated. Since the total amount of supplied oil is calculated as the required amount of oil, the amount of supplied oil is insufficient, and normally, it is conceivable that hydraulic pressure is preferentially supplied to the hydraulic actuator side with a small operating load.

  However, in this case, in this embodiment, the flow rate ratio between the first control valve 8 and the second control valve 9 is the first operation by the cooperation of the first pressure compensation valve 11 and the second pressure compensation valve 12. This corresponds to the required oil amount ratio set by the means 21 and the second operating means 22, and in the above example, since both the first operating means 21 and the second control means 22 are in the maximum operating state, the total supplied oil quantity Half of each is supplied to the first hydraulic actuator 5 and the second hydraulic actuator 6.

  Also, for example, when the first operating means 21 is in an 80% operating state and the second control means 22 is in a 20% operating state, that is, the first variable displacement hydraulic pump 2 and the second variable displacement hydraulic pressure. The total amount of oil supplied from the pump 3 matches the total required oil amount on the control valves 8 and 9 side. Therefore, although the supply oil amount is not excessive or insufficient, the required oil amount of the first control valve 8 and the above When there is a difference in the required oil amount of the second control valve 9, the total supplied oil amount is distributed to the ratio of the required oil amounts of the control valves 8 and 9, and the first hydraulic actuator 5 80% of the supplied oil amount is supplied to the second hydraulic actuator 6 and 20% of the total supplied oil amount is supplied.

  Further, for example, when the first operating means 21 is in the 80% operating state and the second control means 22 is in the 50% operating state, that is, the first variable displacement hydraulic pump 2 and the second variable displacement hydraulic pressure. If the total amount of oil supplied from the pump 3 is insufficient relative to the total required amount of oil on the control valves 8 and 9 side, it is not possible to increase the amount of oil supplied to compensate for the shortage. The shortage of the total supply oil amount is distributed as it is to the ratio of the required oil amounts of the control valves 8 and 9, and the first hydraulic actuator has “80/130” of the total supply oil amount, The second hydraulic actuator is supplied with “50/130” of the total supply oil amount. Therefore, although the operating speed is reduced on the side of the hydraulic actuators 5 and 6 due to insufficient oil amount, the operating speed ratio between the hydraulic actuators 5 and 6 is the operation signal from the operating means 21 and 22. It corresponds to the ratio of.

  The first variable displacement hydraulic pump 2 and the second variable displacement hydraulic pump 3 always bear half of the total required oil amount as the supply oil amount.

IV-3: When switching the merging valve 10 from the shut-off state to the connected state When the merging valve 10 is switched from the shut-off state to the connected state, in the shut-off state, the first variable is performed under the first operating characteristic. An oil amount corresponding to an operation signal from the first operating means 21 is supplied from the displacement hydraulic pump 2 to the first hydraulic actuator 5 via the first control valve 8, and the second variable displacement hydraulic pump. 3, the oil amount corresponding to the operation signal from the second operation means 22 has been supplied to the second hydraulic actuator 6 via the second control valve 9. The amount of oil corresponding to the operation signal from the first operation means 21 from both the first variable displacement hydraulic pump 5 and the second variable displacement hydraulic pump 6 is transferred via the first control valve 8. 1st hydraulic actuator The oil amount corresponding to the operation signal from the second operating means 22 is supplied to the second hydraulic actuator 6 via the second control valve 9. At the time of switching 10, the first operating characteristic is in each state, so there is no excess or deficiency in the pump discharge oil amount relative to the control valve required oil amount, and a change in the inflow oil amount to each hydraulic actuator 5, 6 occurs do not do.

  Here, the operator usually maintains the current operation state regardless of the switching to the merging valve 10. Therefore, the fact that the merging valve 10 is switched from the shut-off state to the connected state means that the required oil amount based on the operator's intention has been changed from the first operation characteristic to the second operation characteristic. The first control valve 8 side secures the required oil amount by the amount of oil supplied from the first variable displacement hydraulic pump 5, and the second control valve 9 side secures the required oil amount to the second variable amount. From the state in which the amount of oil supplied from the displacement hydraulic pump 6 is secured, the required oil amount on the first control valve 8 side and the required oil amount on the second control valve side are set to the first variable displacement hydraulic pump 2. And the second variable displacement hydraulic pump 3 are shifted to a state secured by the total amount of oil supplied from both the first variable displacement hydraulic pump 2 and the second variable displacement hydraulic pump 2. The amount of oil supplied to the hydraulic pump 3 Shows that from the supply amount of oil before switching 0 need to control the increasing direction.

  Therefore, for example, when the switching of the merging valve 10 and the change of the operating characteristics are executed simultaneously, the amount of oil supplied to the first variable displacement hydraulic pump 5 and the second variable displacement hydraulic pump 6 is immediately after that. It is conceivable that the operation switching to the increase side is instantaneously performed, the amount of oil supplied to the first hydraulic actuator 5 and the second hydraulic actuator 6 increases rapidly, and a shock occurs due to sudden acceleration.

  However, in this embodiment, when the switching means 24 receives a switching signal from the shutoff state of the merging valve to the connected state, the switching signal is first sent to the merging valve 10 side so as to place the merging valve 10 in the connected state. Thereafter, the control operation signal corresponding to the operation signals from the first operation means 21 and the second operation means 22 is gradually changed from the first operation characteristic to the second operation characteristic, and the first control is performed. While outputting to the valve 8 and the second control valve 9, the discharge oil amount control signal corresponding to the operation signals from the first operation means 21 and the second operation means 22 is changed from the first operation characteristic to the second operation characteristic. Is gradually changed to output to the first variable displacement hydraulic pump 2 and the second variable displacement hydraulic pump 3.

  For this reason, first, the merging valve 10 is connected, and both the first variable displacement hydraulic pump 2 and the second variable displacement hydraulic pump 3 are connected to the first hydraulic actuator 5 and the second hydraulic actuator 6. After the hydraulic pressure can be supplied, the operation characteristics of the first control valve 8 and the second control valve 9 are gradually changed from the first operation characteristic to the second operation characteristic, and the first variable The supply oil amount of the displacement hydraulic pump 2 and the second variable displacement hydraulic pump 3 is gradually increased from the supply oil amount corresponding to the first operation characteristic to the supply oil amount corresponding to the second operation characteristic. It becomes. As a result, sudden changes in the amount of oil supplied to the first hydraulic actuator 5 and the second hydraulic actuator 6 are avoided, and the first hydraulic actuator 5 and the second hydraulic actuator 6 continue to operate smoothly with almost no shock. Will do.

IV-4: At the time of switching from the connected state of the merging valve 10 to the cut-off state When the merging valve 10 is switched from the connected state to the cut-off state, in the connected state, the first variable is performed under the second operating characteristic. The total supply oil amount from the displacement type hydraulic pump 5 and the second variable displacement type hydraulic pump 6 is the oil amount corresponding to the operation signal from the first operation means 21 in the first hydraulic actuator. 8 and an oil amount corresponding to an operation signal from the second operating means 22 is supplied to the second hydraulic actuator via the second control valve 9, the connected state is cut off. In accordance with the switching to, an oil amount corresponding to an operation signal from the first operating means 21 from the first variable displacement hydraulic pump 2 causes the first control valve 8 to move under the first operating characteristic. Via the first hydraulic actuator An oil amount corresponding to an operation signal from the second operation means 22 is supplied from the second variable displacement hydraulic pump 6 to the second hydraulic actuator 6 through the second control valve 9. It will move to the state to be done.

  Here, the operator usually maintains the current operation state regardless of the switching to the merging valve 10. Therefore, the fact that the merging valve 10 is switched from the connected state to the shut-off state means that the required oil amount based on the operator's intention has been changed from the first operating characteristic to the second operating characteristic. Is the sum of the required oil amount on the first control valve 8 side and the required oil amount on the second control valve 9 side from both the first variable displacement hydraulic pump 2 and the second variable displacement hydraulic pump 3. From the state of securing the supply oil amount oil, the required oil amount is ensured by the amount of oil supplied from the first variable displacement hydraulic pump 2 on the first control valve 8 side, and the above-mentioned on the second control valve 9 side. It means that the required oil amount is secured by the amount of oil supplied from the second variable displacement hydraulic pump 6, which means that the first variable displacement hydraulic pump 2 and the second variable displacement hydraulic pressure. The amount of oil supplied to the pump 3 is It indicates that it is necessary to control the reduction side from the supply amount of oil before switching valve.

  Therefore, for example, when the switching of the merging valve 10 and the change of the operating characteristics are executed simultaneously, the amount of oil supplied to the first variable displacement hydraulic pump 2 and the second variable displacement hydraulic pump 3 is immediately after that. The operation switching to the decrease side is instantaneously performed, the amount of oil supplied to the first hydraulic actuator 5 and the second hydraulic actuator 6 is suddenly reduced, and a shock is generated by sudden deceleration.

  However, in this embodiment, when the switching signal from the connection state of the merging valve 10 to the cutoff state is received from the switching means 24, the operation signals from the first operating means 21 and the second operating means 22 are displayed. The corresponding control operation signal is gradually changed from the second operation characteristic to the first operation characteristic and output to the control valve, and the operation signal corresponding to the operation signal from the first operation means 21 and the second operation means 22 is output. The discharge oil amount control signal is gradually changed from the second operation characteristic to the first operation characteristic and is output to the first variable displacement hydraulic pump 2 and the second variable displacement hydraulic pump 3, and the first operation characteristic is output. After the change is completed, a switching signal is output so that the merging valve 10 is shut off.

  Therefore, first, the operation characteristics of the first control valve 8 and the second control valve 9 are gradually changed from the second operation characteristic to the first operation characteristic, and the first variable displacement hydraulic pump 2 and The supply oil amount of the second variable displacement hydraulic pump 3 is gradually decreased from the supply oil amount corresponding to the second operation characteristic to the supply oil amount corresponding to the first operation characteristic, and then the merging valve 10 is It will be cut off. As a result, the difference in the amount of oil supplied to the first hydraulic actuator 5 and the second hydraulic actuator 6 before and after the state switching of the merging valve 10 disappears as much as possible, and the first hydraulic actuator 5 and the second hydraulic actuator No. 6 will continue to operate smoothly with almost no shock.

V: Others (1) In the above embodiment, the first pressure compensation valve 11 and the second pressure compensation valve 12 in which the pressure compensation means is disposed on the downstream side of the first control valve 8 and the second control valve 9, respectively. In addition to such a configuration as the pressure compensation means, for example, a flow control valve is arranged on the upstream side of the first control valve 8 and the second control valve 9 respectively. You can also However, in such a configuration, since there is no proportional distribution function when the supply flow rate becomes insufficient, the total required oil amount of the first control valve 8 and the second control valve 9 in the merged state is the total pump discharge oil amount. It is necessary to correct the command values to the first control valve 8 and the second control valve 9 by the controller 20 so as to be as follows.

It is a hydraulic circuit diagram in the control apparatus of the hydraulic actuator which concerns on embodiment of this invention. It is a principal part enlarged view of the action | operation control part in FIG. It is a principal part enlarged view of the hydraulic pressure supply part in FIG. It is an operation characteristic explanatory view of a control valve. It is an operation characteristic figure of the operation means at the time of a connection state and a cutoff state.

Explanation of symbols

1 .. Engine 2 .. 1st variable displacement hydraulic pump 3 .. 2nd variable displacement hydraulic pump 4 .. Hydraulic pump 5 .. 1st hydraulic actuator 6 .. 2nd hydraulic actuator 7. First control valve 9 ·· Second control valve 10 ·· Merge valve 11 ·· First pressure compensation valve 12 ·· Second pressure compensation valve 13 ·· Electromagnetic proportional pressure reducing valve 14 ·· Electromagnetic proportional pressure reducing valve 15 ·· Electromagnetic Proportional pressure reducing valve 16 ·· Electromagnetic proportional pressure reducing valve 17 ·· Electromagnetic switching valve 18 ·· Electromagnetic proportional pressure reducing valve 19 ·· Electromagnetic proportional pressure reducing valve 20 ·· Controller 21 ·· First operating means 22 ·· Second operating means 23 · · Operation characteristics 24 · · Switching means 25 · · Control cylinder 27 · · Control spool 29 · · Control piston 31 · · First supply oil passage 32 · · Second supply oil passage 33 · · Oil passage 34 · · Oil Road 35 - oil passage 36 ... oil passage 37 .. connecting oil channel 40 ... lever 41 ... lever 44 ... compression spring 45 ... spring 46 ... shuttle valve

Claims (3)

A first variable displacement hydraulic pump;
A hydraulic actuator disposed corresponding to the first variable displacement hydraulic pump;
A control valve disposed between the first variable displacement hydraulic pump and the first hydraulic actuator to drive and control the hydraulic actuator by supplying and discharging hydraulic pressure to the hydraulic actuator;
Operating means for outputting an operation signal for operating the control valve;
A second variable displacement hydraulic pump;
It is arranged between the supply oil passage connecting the first variable displacement hydraulic pump and the control valve and the discharge oil passage of the second variable displacement hydraulic pump, and the supply oil passage and the discharge oil passage are connected or cut off. A merging valve to be in a state;
Switching means for outputting a switching signal for switching the junction valve between a connected state and a shut-off state,
The control valve is configured to be able to supply a total oil amount of the supply oil amount from the first variable displacement hydraulic pump and the supply oil amount from the second variable displacement hydraulic pump to the hydraulic actuator,
As the operation characteristic in the control operation of the hydraulic actuator by the control valve, the first operation characteristic in which the control operation is performed with the amount of oil supplied from the first variable displacement hydraulic pump under the shutoff state of the merging valve, and the switching And a second operating characteristic for performing the control operation with the total amount of oil supplied from the first variable displacement hydraulic pump and the second variable displacement hydraulic pump under the connected state of the means,
When receiving a switching signal from the switching means to the shutoff state of the merging valve, the required oil amount required to drive the hydraulic actuator based on the operation of the operating means is calculated by the first operating characteristic. Then, a discharge oil amount control signal is output to the first variable displacement hydraulic pump to supply the supply oil amount corresponding to the required oil amount from the first variable displacement hydraulic pump, and the required oil amount is output to the hydraulic pressure. While outputting a control operation signal to the control valve to supply to the actuator,
When receiving a switching signal from the switching means to the connection state of the merging valve, the required oil amount required to drive the hydraulic actuator based on the operation of the operating means is calculated from the second operating characteristic. Then, the first variable displacement hydraulic pump and the second variable displacement hydraulic pump are supplied to the first variable displacement hydraulic pump and the second variable displacement hydraulic pump so that the supply oil amount corresponding to the required oil amount is supplied from the first variable displacement hydraulic pump and the second variable displacement hydraulic pump. In a hydraulic actuator control device comprising a controller that outputs a discharge oil amount control signal and outputs a control operation signal to the control valve to supply the required oil amount to the hydraulic actuator;
In the first operating characteristic, the controller calculates the maximum amount of oil supplied from the first variable displacement hydraulic pump as the required oil amount when the operating means is operated maximum, and in the second operating characteristic, the operating means The maximum total supply oil amount from the first variable displacement hydraulic pump and the second variable displacement hydraulic pump is calculated as the required oil amount during the maximum operation of
When a switching signal from the shut-off state of the junction valve to the connection state is received from the switching means, a control operation signal corresponding to the operation signal from the operation means is output after the switching signal is output to bring the junction valve into the connection state Is gradually changed from the first operation characteristic to the second operation characteristic and output to the control valve, and the discharge oil amount control signal corresponding to the operation signal from the operation means is changed from the first operation characteristic to the above-mentioned control valve. Gradually change to the second operating characteristic and output to the first variable displacement hydraulic pump and the second variable displacement hydraulic pump,
When the switching means receives a switching signal from the connection state to the cutoff state of the junction valve, the control operation signal corresponding to the operation signal from the operation means is gradually changed from the second operation characteristic to the first operation characteristic. The discharge oil amount control signal corresponding to the operation signal from the operation means is gradually changed from the second operation characteristic to the first operation characteristic to output the first variable displacement hydraulic pressure. A hydraulic actuator control device characterized in that a switch signal is outputted to output to the pump and the second variable displacement hydraulic pump, and after the change to the first operating characteristic is completed, the switching valve is put into a shut-off state. A first variable displacement hydraulic pump;
A first hydraulic actuator disposed corresponding to the first variable displacement hydraulic pump;
A first control valve disposed between the first variable displacement hydraulic pump and the first hydraulic actuator to drive and control the first hydraulic actuator by supplying and discharging hydraulic pressure to and from the first hydraulic actuator;
First operating means for outputting an operation signal for operating the first control valve;
A second variable displacement hydraulic pump;
A second hydraulic actuator disposed corresponding to the second variable displacement hydraulic pump;
A second control valve disposed between the second variable displacement hydraulic pump and the second hydraulic actuator to drive and control the second hydraulic actuator by supplying and discharging hydraulic pressure to and from the second hydraulic actuator;
Second operating means for outputting an operation signal for operating the second control valve;
The first hydraulic pressure is operated by a differential pressure between a downstream hydraulic pressure that is arranged downstream of the first control valve and flows out of the first control valve, and a pilot hydraulic pressure that is generated by slightly reducing the downstream hydraulic pressure. A first pressure compensation valve that controls the amount of oil supplied to the actuator, a downstream hydraulic pressure that is arranged downstream of the second control valve and flows out of the second control valve, and slightly reduces the downstream hydraulic pressure. A second pressure compensation valve that operates by a differential pressure with the generated pilot hydraulic pressure and controls the amount of oil supplied from the second control valve to the second hydraulic actuator, and the pilot oil passage of the first pressure compensation valve And the pilot oil passage of the second pressure compensation valve are connected to each other, the high pressure side pilot hydraulic pressure is applied to both the first pressure compensation valve and the second pressure compensation valve. Differential pressure between upstream and downstream of valve The required oil amount set by the first operating means and the second operating means with the same differential pressure between the upstream side and the downstream side of the second control valve and the flow rate ratio between the first control valve and the second control valve A pressure compensation means corresponding to the ratio;
Between a first supply oil passage connecting the first variable displacement hydraulic pump and the first control valve, and a second supply oil passage connecting the second variable displacement hydraulic pump and the second control valve. A merging valve arranged to connect or shut off the first supply oil passage and the second supply oil passage, and the pilot oil passage on the first pressure compensation valve side and the pilot oil passage on the second pressure compensation valve side. When,
Switching means for outputting a switching signal for switching the junction valve between a connected state and a shut-off state;
The first control valve is configured to be able to supply a total oil amount of a supply oil amount from the first variable displacement hydraulic pump and a supply oil amount from the second variable displacement hydraulic pump to the first hydraulic actuator,
The second control valve is configured to be able to supply the total amount of oil supplied from the first variable displacement hydraulic pump and the amount of oil supplied from the second variable displacement hydraulic pump to the second hydraulic actuator. ,
As an operation characteristic in the control operation of the first hydraulic actuator and the second hydraulic actuator by the first control valve and the second control valve, the operation of the first hydraulic actuator by the first control valve under the shutoff state of the merging valve. The control operation is performed with the amount of oil supplied from the first variable displacement hydraulic pump, and the control operation of the second hydraulic actuator with the second control valve is performed with the amount of oil supplied from the second variable displacement hydraulic pump. 1 operation characteristic, and the control operation of the first hydraulic actuator by the first control valve and the control operation of the second hydraulic actuator by the second control valve in the connected state of the merging valve, respectively. A second operating characteristic performed by the total amount of oil supplied from the hydraulic pump and the second variable displacement hydraulic pump;
When receiving a switching signal from the switching means to the shut-off state of the merging valve, the required amount of oil required to drive the first hydraulic actuator based on the operation of the first operating means is set to the first A discharge oil amount control signal is output to the first variable displacement hydraulic pump so that the supply oil amount calculated from the operation characteristics and corresponding to the required oil amount is supplied from the first variable displacement hydraulic pump. Based on the operation of the operating means, the required oil amount required for driving the second hydraulic actuator is calculated from the first operating characteristic, and the supply oil amount corresponding to the required oil amount is calculated as the second variable displacement hydraulic pressure. A discharge oil amount control signal is output to the second variable displacement hydraulic pump to be supplied from the pump, and the required oil amount is supplied to the first hydraulic actuator and the second hydraulic actuator. While outputting the control operation signal to the control valve and the second control valve,
When receiving a switching signal from the switching means to the connection state of the merging valve, the required oil amount required to drive the first hydraulic actuator based on the operation of the first operating means, and the first The required oil amount required to drive the second hydraulic actuator based on the operation of the two operating means is calculated from the second operation characteristic, and the supply oil amount corresponding to the total required oil amount is calculated as the first required oil amount. A discharge oil amount control signal is output to the first variable displacement hydraulic pump and the second variable displacement hydraulic pump so as to be supplied from the first variable displacement hydraulic pump and the second variable displacement hydraulic pump. In a hydraulic actuator control device comprising a controller for outputting a control signal to the first control valve and the second control valve to be supplied to the first hydraulic actuator and the second hydraulic actuator
The controller calculates, as the required oil amount, the maximum amount of oil supplied from the first variable displacement hydraulic pump during the maximum operation of the first operation means in the first operation characteristic, and the maximum of the second operation means. The maximum oil supply amount from the second variable displacement hydraulic pump is calculated as a required oil amount during operation, and the first variable displacement hydraulic pump is operated when the first operation means is operated maximum in the second operation characteristic. And the maximum total supply oil amount from the second variable displacement hydraulic pump is calculated as a required oil amount, and the maximum oil supply amount from the first variable displacement hydraulic pump and the second variable displacement hydraulic pump when the second operation means is maximum operated. The maximum oil supply amount is calculated as the required oil amount,
When a switching signal from the shut-off state of the merging valve to the connected state is received from the switching means, a switching signal is output to bring the merging valve into a connected state, and then from the first operating means and the second operating means. A control operation signal corresponding to the operation signal is gradually changed from the first operation characteristic to the second operation characteristic and is output to the first control valve and the second control valve, and the first operation means and the second operation valve are output. The discharge oil amount control signal corresponding to the operation signal from the two operation means is gradually changed from the first operation characteristic to the second operation characteristic to thereby change the first variable displacement hydraulic pump and the second variable displacement hydraulic pressure. Each output to the pump,
When a switching signal from the connected state of the junction valve to the shut-off state is received from the switching means, the control operation signal corresponding to the operation signal from the first operating means and the second operating means is changed from the second operating characteristic to the second operating characteristic. Gradually change to one operation characteristic and output to the first control valve and the second control valve, and the discharge oil amount control signal corresponding to the operation signal from the first operation means and the second operation means Gradually change from the second operating characteristic to the first operating characteristic and output to the first variable displacement hydraulic pump and the second variable displacement hydraulic pump, and the merging valve after the change to the first operating characteristic is completed A hydraulic actuator control device, characterized in that a switching signal is output so as to put the motor in a shut-off state. In claim 2,
When the merging valve is in the connected state, approximately half of the total required oil amount of the first control valve and the second control valve corresponding to the operation signals from the first operation means and the second operation means is reduced. The first variable displacement hydraulic pump and the second variable displacement hydraulic pump bear the supply oil amount, respectively, and the discharge oil amount control is performed on the first variable displacement hydraulic pump and the second variable displacement hydraulic pump. A hydraulic actuator control device characterized in that a signal is output.

Images