JP7370854B2 - Actuator control device - Google Patents

Description

The present disclosure relates to an actuator control device that controls the operation of an actuator.

Actuators driven by working fluids are used in various machines such as construction machines. The actuator driven by the working fluid is, for example, a hydraulic cylinder such as a hydraulic cylinder. As hydraulic cylinders included in construction machines, there are a boom cylinder that drives a boom, an arm cylinder that drives an arm, and a bucket cylinder that drives a bucket.

A conventional actuator control device for controlling the operation of an actuator includes a control valve provided between the actuator and a source and tank of working fluid. The control valve includes a single axially movable spool. Meter-in/meter-out control is performed to adjust the flow rate of working fluid supplied to the hydraulic cylinder and the flow rate of working fluid discharged from the hydraulic cylinder depending on the position of the spool in the axial direction. A conventional actuator control device that performs meter-in/meter-out control using a control valve having a single spool is disclosed in, for example, Japanese Patent Laid-Open No. 2003-269411.

In order to appropriately perform meter-in/meter-out control using a single spool, it is necessary to provide grooves (also called "throttles") extending in the circumferential direction around the shaft at appropriate positions on the outer surface of the spool. The position and size of the aperture on the spool are adjusted using test data obtained by actually operating the actuator to be controlled on a prototype spool. Prototype production typically requires multiple iterations.

As described above, an actuator control device that performs meter-in/meter-out control using a single spool has a problem in that it is difficult to provide an appropriate throttle to the spool. Therefore, an IMV (Independent Metering Valve) type actuator control device that performs meter-in control and meter-out control by independently controlling the positions of a plurality of spools has been proposed. A conventional IMV type actuator control device is disclosed in Japanese Patent Laid-Open No. 2001-003905.

JP2003-269411A Japanese Patent Application Publication No. 2001-003905

Conventional actuator control devices that use IMV have two spools for meter-in control, two spools for meter-out control, and the positions of these four spools can be controlled independently. It is equipped with four electromagnetic proportional valves. In other words, the conventional IMV type actuator control device has four spools and four electromagnetic proportional valves.

It is an objective of the present disclosure to alleviate or solve at least some of the conventional problems mentioned above. One of the specific objectives of the present disclosure is to realize an actuator control device that performs meter-in/meter-out control with a simpler configuration. Other objects of the present disclosure will become apparent throughout the description.

An actuator control device according to an embodiment of the present invention includes a meter-out valve that discharges working fluid from a first fluid pressure chamber of an actuator to a tank using a first pilot pressure or a second pilot pressure; a meter-in valve that outputs the working fluid from the working fluid source to a second fluid pressure chamber of the actuator using a second pilot pressure; and a switching mechanism configured to output one of the pressure and the second pilot pressure to the meter-out valve and output the other to the meter-in valve.

In one embodiment of the invention, the switching mechanism is switched by movement of the meter-out valve.

In one embodiment of the present invention, the switching mechanism is configured to have a first position that outputs the first pilot pressure to the meter-out valve or a second position that outputs the first pilot pressure to the meter-in valve. It has a selector valve and a second selector valve that can be switched to a third position where the second pilot pressure is output to the meter-in valve or a fourth position where the second pilot pressure is output to the meter-out valve.

In one embodiment of the present invention, the switching mechanism switches the first selector valve to the first position in response to receiving the first pilot pressure when the second pilot pressure is not supplied. switching the second selector valve to the third position;

In one embodiment of the present invention, the switching mechanism switches the first selector valve to the second position in response to receiving the second pilot pressure when the first pilot pressure is not supplied. switching the second selector valve to the fourth position;

In one embodiment of the present invention, the meter-in valve outputs the working fluid to the actuator according to the first pilot pressure or the second pilot pressure.

In one embodiment of the invention, the meter-out valve discharges the working fluid from the actuator in response to the first pilot pressure or the second pilot pressure.

In one embodiment of the invention, the meter-in valve is provided between the actuator and a first working fluid source and a second working fluid source.

In one embodiment of the present invention, the meter-in valve has a position where the working fluid is output to the actuator from either one of the first working fluid source and the second working fluid source, and the first working fluid source and the second working fluid source. and a position for outputting said working fluid to said actuator from both other sources of working fluid.

According to the embodiments of the present invention, an actuator control device that performs meter-in control and meter-out control using a plurality of spools can be realized with a simpler configuration.

1 is a diagram schematically showing an actuator control device according to an embodiment of the present invention. FIG. 2 is a diagram illustrating an operation of contracting an actuator in the actuator control device of FIG. 1. FIG. In FIG. 2a, the meter-out valve 6 is in communication with the first fluid pressure chamber 8a of the actuator 8. In FIG. FIG. 2 is a diagram illustrating an operation of contracting an actuator in the actuator control device of FIG. 1. FIG. In FIG. 2b, the meter-out valve 6 communicates with the first fluid pressure chamber 8a of the actuator 8, and the meter-in valve 5 communicates with the second fluid pressure chamber 8b of the actuator 8. FIG. 2 is a diagram illustrating an operation of extending an actuator in the actuator control device of FIG. 1. FIG. 2 is a diagram schematically showing the actuator control device of FIG. 1. FIG. In FIG. 3a, the meter-out valve 6 is in communication with the second fluid pressure chamber 8b of the actuator 8. In FIG. FIG. 2 is a diagram illustrating an operation of extending an actuator in the actuator control device of FIG. 1. FIG. In FIG. 3b, the meter-out valve 6 communicates with the second fluid pressure chamber 8b of the actuator 8, and the meter-in valve 5 communicates with the first fluid pressure chamber 8a of the actuator 8. FIG. 6 is a diagram schematically showing an actuator control device according to another embodiment of the present invention.

Hereinafter, various embodiments of the present invention will be described with reference to the drawings as appropriate. Note that common constituent elements in the plurality of drawings are given the same reference numerals throughout the plurality of drawings. It should be noted that the drawings are not necessarily drawn to scale for illustrative purposes. In each drawing, some components may be omitted for convenience of explanation.

The present invention can be applied to an actuator control device that controls the operation of a fluid pressure actuator partitioned into at least two fluid pressure chambers. With reference to FIG. 1, an actuator control device according to one embodiment of the present invention will be described.

FIG. 1 is a diagram schematically showing an actuator control device 1 according to an embodiment of the present invention. The actuator control device 1 drives the member to be driven by operating the actuator 8 . The members driven by the actuator 8 are, for example, a boom, an arm, a bucket of a construction machine, and other movable members of the construction machine. The actuator control device 1 can be applied to various machines other than construction machines.

In the illustrated embodiment, the actuator control device 1 includes a working fluid source 2 that supplies working fluid to the actuator 8, a tank 3 that stores the working fluid discharged from the actuator 8, a check valve 4, and a meter-in valve 5. , a meter-out valve 6, a controller 10, a switching mechanism 20, a first electromagnetic proportional valve 31, and a second electromagnetic proportional valve 32.

The working fluid source 2 discharges working fluid. The working fluid discharged from the working fluid source 2 is output to the actuator 8 via the meter-in valve 5. The working fluid source 2 is, for example, a variable displacement pump that can adjust the amount of working fluid to be discharged. A check valve 4 for maintaining negative pressure is provided between the working fluid source 2 and the meter-in valve 5.

The actuator 8 is, for example, a hydraulic actuator driven by a working fluid. The actuator 8 may be a hydraulic actuator driven by hydraulic oil. The actuator 8 may be a pneumatic actuator operated by compressed air or any hydraulic actuator operated by a working fluid other than these. The actuator control device 1 may include a plurality of actuators.

The actuator 8 is partitioned into a first fluid pressure chamber 8a and a second fluid pressure chamber 8b by a piston 8c provided in a hollow cylinder. The cylinder of the actuator 8 is configured such that one longitudinal end thereof is open and the other is closed. A piston rod 8d is connected to the piston 8c. A portion of the piston rod 8d protrudes outside the cylinder. The tip of the piston rod 8d is connected to a movable member such as a boom, arm, or bucket. The actuator 8 may include a position sensor that detects the position of the piston 8c. This position sensor is, for example, a linear variable differential transformer (LVDT).

The controller 10 includes a processor that performs various calculation processes, a memory that stores various programs and data, and a device interface that connects to various sensors and other devices. The controller 10 can adjust the flow rate of the pilot pressure output from the electromagnetic proportional valves 31 and 32 by outputting control pulses to the electromagnetic proportional valves 31 and 32. When the actuator control device 1 is installed in a construction machine, the controller 10 receives a control signal related to the operation of the control lever of the construction machine, and controls the electromagnetic proportional valve 31 and the electromagnetic proportional valve 32 according to the control signal. can be controlled.

The first proportional electromagnetic valve 31 and the second proportional electromagnetic valve 32 are connected to a pilot pressure source (not shown). The first proportional electromagnetic valve 31 is connected to the switching mechanism 20 through a flow path 13a, and the second proportional electromagnetic valve 32 is connected to the switching mechanism 20 through a flow path 13d. The first electromagnetic proportional valve 31 includes a solenoid coil, a drive rod that is driven by the solenoid coil and moves in the axial direction, and a pilot spool that moves in the axial direction by the thrust received from the drive rod. The first proportional electromagnetic valve 31 itself and the second proportional electromagnetic valve 32 themselves may be known proportional electromagnetic valves. The current applied to the solenoid coil is determined according to control pulses from the controller 10. The first electromagnetic proportional valve 31 is provided with a flow path that communicates the pilot pressure source with the flow path 13a. The opening area of this flow path changes depending on the axial position of the pilot spool. The first electromagnetic proportional valve 31 can output pilot fluid from the pilot pressure source to the flow path 13a at a flow rate that corresponds to an opening area that changes depending on the axial position of the pilot spool. The second electromagnetic proportional valve 32 includes the same components as the first electromagnetic proportional valve 31. The second electromagnetic proportional valve 32 can supply pilot fluid from the pilot pressure source to the flow path 13d at a flow rate that corresponds to the opening area that changes depending on the axial position of the pilot spool. In this specification, the pilot fluid or pilot pressure output from the first electromagnetic proportional valve 31 is referred to as a first pilot pressure, and the pilot fluid or pilot pressure output from the second electromagnetic proportional valve 32 is referred to as a second pilot pressure. I may call you.

The meter-in valve 5 is provided between the actuator 8 and the working fluid source 2. The first fluid pressure chamber 8a of the actuator 8 is connected to the meter-in valve 5 through a first port P1, a flow path 11a, and a flow path 11b. The second fluid pressure chamber 8b of the actuator 8 is connected to the meter-in valve 5 through a port P2, a flow path 11d, and a flow path 11e. The meter-in valve 5 is also connected to a switching mechanism 20 to receive pilot pressure. Specifically, the meter-in valve 5 is connected to the switching mechanism 20 through a flow path 13b and a flow path 13e. The meter-in valve 5 has at least one pilot pressure receiving chamber. Pilot pressure is output from the first electromagnetic proportional valve 31 or the second electromagnetic proportional valve 32 to the at least one pilot pressure receiving chamber of the meter-in valve 5 in response to switching of the switching mechanism 20.

The meter-in valve 5 has a spool housed in the interior space of the manifold. The spool of the meter-in valve 5 is sometimes called a meter-in valve spool. The meter-in valve 5 can switch the flow path connecting the meter-in valve 5 and the actuator 8 by displacing the meter-in valve spool in the axial direction using pilot pressure from the electromagnetic proportional valve 31 or the second electromagnetic proportional valve 32. It is configured as follows. Specifically, the meter-in valve 5 has a first communication position 5X that outputs the working fluid from the working fluid source 2 to the first fluid pressure chamber 8a through the flow path 11b, the flow path 11a, and the first port P1; A shutoff position 5Y that cuts off the output of the working fluid to each fluid pressure chamber 8a, 8b, and works fluid from the working fluid source 2 to the second fluid pressure through the flow path 11e, the flow path 11d, and the second port P2. It is switched to one of the second communication positions 5Z that outputs to the chamber 8b. In the illustrated embodiment, the meter-in valve 5 is switched to the first communication position 5X by pilot pressure from the first proportional electromagnetic valve 31 and switched to the second communication position 5Z by pilot pressure from the second proportional electromagnetic valve 32. .

The meter-in valve 5 is provided with a flow path that connects the flow path 12a connected to the working fluid source 2 and the flow path 11b or 11e. When the meter-in valve 5 is switched to the first communication position 5X, the flow path of the meter-in valve 5 is connected to the flow path 11b, and the flow path from the working fluid source 2 to the first fluid pressure chamber 8a is opened. Working fluid is output to the first fluid pressure chamber 8a through the flow path. When the meter-in valve 5 is switched to the second communication position 5Z, the flow path of the meter-in valve 5 is connected to the flow path 11e, and the flow path from the working fluid source 2 to the second fluid pressure chamber 8b is opened. The working fluid is output to the second fluid pressure chamber 8b through the flow path. The opening area of the flow path through which the working fluid in the meter-in valve 5 passes changes depending on the axial position of the meter-in valve spool. The axial position of the meter-in valve spool is adjusted by the first pilot pressure or the second pilot pressure output to the pilot pressure receiving chamber of the meter-in valve 5. In this way, the meter-in valve 5 transfers the working fluid from the fluid pressure source 2 to the first fluid at a flow rate corresponding to the opening area of the flow path in the meter-in valve 5, which changes according to the axial position of the meter-in valve spool. It can be selectively output to the pressure chamber 8a or the second fluid pressure chamber 8b. The opening area of the flow path through which the working fluid in the meter-in valve 5 passes is adjusted by adjusting the first pilot pressure or the second pilot pressure and displacing the axial position of the meter-in valve spool. In this way, the meter-in valve 5 can output the working fluid to the actuator 8 at a flow rate depending on the first pilot pressure or the second pilot pressure.

A meter-out valve 6 is provided between the actuator 8 and the tank 3. The first fluid pressure chamber 8a of the actuator 8 is connected to the meter-out valve 6 through a first port P1, a flow path 11a, and a flow path 11c. The second fluid pressure chamber 8b of the actuator 8 is connected to the meter-out valve 6 through a second port P2, a flow path 11d, and a flow path 11f. Further, the meter-out valve 6 is also connected to the switching mechanism 20 in order to receive pilot pressure supply. Specifically, the meter-out valve 6 is connected to the switching mechanism 20 through a flow path 13c and a flow path 13f. The meter-out valve 6 has at least one pilot pressure receiving chamber. Pilot pressure is output from the first electromagnetic proportional valve 31 or the second electromagnetic proportional valve 32 to the at least one pilot pressure receiving chamber of the meter-out valve 6 in response to switching of the switching mechanism 20.

The meter-out valve 6, like the meter-in valve 5, has a spool housed in the internal space of the manifold. The spool of the meter-out valve 6 is sometimes called a meter-out valve spool. The meter-out valve 6 switches the flow path connecting the meter-out valve 6 and the actuator 8 by displacing the meter-out valve spool in the axial direction using pilot pressure from the electromagnetic proportional valve 31 or the second electromagnetic proportional valve 32. It is configured so that it can be done. Specifically, the meter-out valve 6 is located at a first discharge position 6X where the working fluid in the first fluid pressure chamber 8a is discharged into the tank 3 via the first port P1, the flow path 11a, the flow path 11c, and the flow path 12b. , a blocking position 6Y that blocks the discharge of the working fluid from each fluid pressure chamber 8a, 8b, and a blocking position 6Y that blocks the discharge of the working fluid from each fluid pressure chamber 8a, 8b, and the working fluid in the second fluid pressure chamber 8b is passed through the second port P2, the flow path 11d, the flow path 11f, and the flow path 12b. The second discharge position 6Z is switched to one of the second discharge positions 6Z for discharging the liquid to the tank 3. In the illustrated embodiment, the meter-out valve 6 is switched to the first discharge position 6X by pilot pressure from the first proportional solenoid valve 31 and to the second discharge position 6Z by pilot pressure from the second proportional solenoid valve 32. It will be done.

The meter-out valve 6 is provided with a flow path that connects the flow path 12b connected to the tank 3 and the flow path 11c or 11f. When the meter-out valve 6 is switched to the first discharge position 6X, the flow path of the meter-out valve 6 is connected to the flow path 11c, and the flow path from the first fluid pressure chamber 8a to the tank 3 is opened. Working fluid is discharged from the first fluid pressure chamber 8a through the flow path. When the meter-in valve 6 is switched to the second discharge position 6Z, the flow path of the meter-out valve 6 is connected to the flow path 11f, and the flow path from the second fluid pressure chamber 8b to the tank 3 is opened. Working fluid is discharged from the second fluid pressure chamber 8b through the passage. The opening area of the flow path through which the working fluid passes within the meter-out valve 6 changes depending on the axial position of the meter-out valve spool. The axial position of the meter-out valve spool is adjusted by the first pilot pressure or the second pilot pressure output to the pilot pressure receiving chamber of the meter-out valve 6. In this way, the meter-out valve 6 receives the working fluid from the fluid pressure source 2 at a flow rate that corresponds to the opening area of the flow path within the meter-out valve 5, which varies according to the axial position of the meter-out valve spool. Can be selectively discharged. The opening area of the flow path through which the working fluid passes within the meter-out valve 6 is adjusted by adjusting the first pilot pressure or the second pilot pressure and displacing the axial position of the meter-in valve spool. In this way, the meter-out valve 6 can discharge the working fluid from the actuator 8 at a flow rate depending on the first pilot pressure or the second pilot pressure.

The switching mechanism 20 switches the flow path between the first proportional electromagnetic valve 31 and the second proportional electromagnetic valve 32 and the meter-in valve 5 and the meter-out valve 6, so that one of the meter-in valve 5 and the meter-out valve 6 is switched between the meter-in valve 5 and the meter-out valve 6. The first pilot pressure from the first proportional electromagnetic valve 31 is outputted to the first proportional electromagnetic valve 31, and the second pilot pressure from the second proportional electromagnetic valve 32 is outputted to the other of the meter-in valve 5 and the meter-out valve 6. Specifically, when outputting the first pilot pressure from the first electromagnetic proportional valve 31 to the meter-in valve 5, the switching mechanism 20 outputs the second pilot pressure from the second electromagnetic proportional valve 32 to the meter-out valve 6. Output to. On the contrary, when outputting the first pilot pressure from the first electromagnetic proportional valve 31 to the meter-out valve 6, the switching mechanism 20 outputs the second pilot pressure from the second electromagnetic proportional valve 32 to the meter-in valve. Output to 5. The switching mechanism 20 switches the flow path based on at least one of the first pilot pressure, the second pilot pressure, and the movement of the meter-out valve 6 (the position of the meter-out valve 6), as will be explained in detail below. It is done on the basis of

The switching mechanism 20 includes a first selector valve 21 and a second selector valve 22. The first selector valve 21 is connected to the first electromagnetic proportional valve 31 through a flow path 13a, connected to the meter-in valve 5 through a flow path 13b, and connected to the meter-out valve 6 through a flow path 13c. The first selector valve 21 has a first position 21X that outputs the first pilot pressure from the first electromagnetic proportional valve 31 to the meter-out valve 6, and a first position 21X that outputs the first pilot pressure from the first electromagnetic proportional valve 31 to the meter-in valve 5. The second position 21Y outputs the output signal. The first selector valve 21 itself and the second selector valve 22 themselves may be known selector valves.

The second selector valve 22 is connected to the second electromagnetic proportional valve 32 through a flow path 13d, to the meter-in valve 5 through a flow path 13e, and to the meter-out valve 6 through a flow path 13f. The second selector valve 22 has a third position 22X that outputs the second pilot pressure from the second electromagnetic proportional valve 32 to the meter-in valve 5, and a third position 22X that outputs the second pilot pressure from the second electromagnetic proportional valve 32 to the meter-out valve 6. The fourth position 22Y outputs the output signal.

When the first proportional solenoid valve 31 is energized while the second proportional solenoid valve 32 is not energized, the first selector valve 21 receives the first pilot pressure from the first proportional solenoid valve 31 and moves to the first position. Can be switched to 21X. When the second proportional electromagnetic valve 32 is not excited, the second pilot pressure is not output from the second proportional electromagnetic valve 32 to the switching mechanism 20. In other words, when the first pilot pressure is output from the first proportional electromagnetic valve 31 while the second pilot pressure is not output from the second proportional electromagnetic valve 32, the first selector valve 21 is moved to the first position 21X. Can be switched. The first selector valve 21 has a push pin 21a connected to the meter-out valve 6. The push pin 21a is pushed into the inside of the first selector valve 21 when the meter-out valve 6 is switched to the second discharge position 6Z while the first pilot pressure is not being output to the first selector valve 21. When the push pin 21a is pushed inside the first selector valve 21, the first selector valve 21 is switched to the second position 21Y. Even if the second pilot pressure is outputted from the second electromagnetic proportional valve 32 to the switching mechanism 20 while the first pilot pressure is outputted to the first selector valve 21, the first selector valve 21 is moved to the first position 21X. The second selector valve 22 remains at the third position 22X. That is, the first pilot pressure from the first electromagnetic proportional valve 31 locks the first selector valve 21 at the first position 21X and the second selector valve 22 at the third position 22X.

When the second selector valve 22 is energized while the first proportional solenoid valve 31 is not energized, the second selector valve 22 receives the second pilot pressure from the second proportional solenoid valve 31 and moves to the fourth position. It can be switched to 22Y. When the first proportional electromagnetic valve 32 is not excited, the first pilot pressure is not output from the first proportional electromagnetic valve 31 to the switching mechanism 20. In other words, when the first pilot pressure is output from the second electromagnetic proportional valve 32 while the first pilot pressure is not output from the first electromagnetic proportional valve 31, the second selector valve 22 moves to the fourth position 22Y. Can be switched. The second selector valve 22 has a push pin 22a connected to the meter-out valve 6. The push pin 22a is pushed into the second selector valve 22 when the meter-out valve 6 is switched to the first discharge position 6X while the second pilot pressure is not being output to the second selector valve 22. When the push pin 22a is pushed into the second selector valve 22, the second selector valve 22 is switched to the third position 22X. Even if the first pilot pressure is output from the first electromagnetic proportional valve 31 to the switching mechanism 20 while the second pilot pressure is being output to the second selector valve 22, the second selector valve 22 is moved to the fourth position 22Y. The first selector valve 21 remains at the second position 21Y. That is, the second pilot pressure from the second electromagnetic proportional valve 32 locks the second selector valve 22 at the fourth position 22Y, and the first selector valve 21 is locked at the second position 21Y.

Next, the operation of the actuator control device 1 will be described with further reference to FIGS. 2a, 2b, 3a, and 3b. At the start of operation, both the first proportional electromagnetic valve 31 and the second proportional electromagnetic valve 32 are not excited, so that pilot pressure is not output from either the first proportional electromagnetic valve 31 or the second proportional electromagnetic valve 32. Assume that you have not. In this case, as shown in FIG. 1, the meter-in valve 5 is in the cutoff position 5Y, and the meter-out valve 6 is in the cutoff position 6Y. Further, the first selector valve 21 and the second selector valve 22 are not locked.

The operation of contracting the actuator 8 will be described with reference to FIGS. 2a and 2b. When contracting the actuator 8, the controller 10 excites the first electromagnetic proportional valve 31. As a result, the first proportional electromagnetic valve 31 opens, and the first pilot pressure is outputted from the first proportional electromagnetic valve 31 to the first selector valve 21 of the switching mechanism 20 . This first pilot pressure causes the first selector valve 21 to be switched to the first position 21X.

By switching the first selector valve 21 to the first position 21X, the first pilot pressure is output to the meter-out valve 6. This first pilot pressure causes the meter-out valve 6 to be switched to the first discharge position 6X, as shown in Figure 2a. As a result, the flow path from the first fluid pressure chamber 8a of the actuator 8 to the tank 3 via the flow path 11a, the flow path 11c, and the flow path 12b is opened. Furthermore, by switching the meter-out valve 6 to the first discharge position 6X, the push pin 22a is pushed into the second selector valve 22, thereby switching the second selector valve 22 to the third position 22X.

Next, the controller 10 energizes the second proportional electromagnetic valve 32 while energizing the first proportional electromagnetic valve 31 to open the second proportional electromagnetic valve 32 . Since the second selector valve 22 has been switched to the third position 22X, the second pilot pressure from the second electromagnetic proportional valve 32 is output to the meter-in valve 5. The second pilot pressure from the second electromagnetic proportional valve 32 switches the meter-in valve 5 to the second communication position 5Z, as shown in FIG. 2b. As a result, the flow path from the working fluid source 2 to the second fluid pressure chamber 8b of the actuator 8 via the flow path 12a, the flow path 11e, and the flow path 11d is opened.

In this way, the working fluid is supplied to the second fluid pressure chamber 8b of the actuator 8 and the working fluid is discharged from the first fluid pressure chamber 8a, so that the actuator 8 can be contracted.

Next, the operation of extending the actuator 8 will be described with reference to FIGS. 3a and 3b. When the actuator 8 is extended when both the first solenoid proportional valve 31 and the second solenoid proportional valve 32 are energized as shown in FIG. 2b, the controller 10 controls the first solenoid proportional valve 31 Then, the excitation of the second electromagnetic proportional valve 32 is stopped, and the locks of the first selector valve 21 and the second selector valve 22 are released. The controller 10 then excites the second proportional electromagnetic valve 32 to open the second proportional electromagnetic valve 32. As a result, the second pilot pressure is outputted from the second electromagnetic proportional valve 32 to the second selector valve 22 of the switching mechanism 20 . This second pilot pressure causes the second selector valve 22 to be switched to the fourth position 22Y.

By switching the second selector valve 22 to the fourth position 22Y, the second pilot pressure is output to the meter-out valve 6. This second pilot pressure switches the meter-out valve 6 to the second discharge position 6Z, as shown in Figure 3a. As a result, the flow path from the second fluid pressure chamber 8b of the actuator 8 to the tank 3 via the flow path 11d, the flow path 11f, and the flow path 12b is opened. Further, by switching the meter-out valve 6 to the second discharge position 6Z, the push pin 21a is pushed into the first selector valve 21, thereby switching the first selector valve 21 to the second position 21Y.

Next, the controller 10 energizes the first proportional electromagnetic valve 31 while energizing the second proportional electromagnetic valve 32 to open the first proportional electromagnetic valve 31 . Since the first selector valve 21 has been switched to the second position 21Y, the first pilot pressure from the first electromagnetic proportional valve 31 is output to the meter-in valve 5. The first pilot pressure from the first electromagnetic proportional valve 31 switches the meter-in valve 5 to the first communication position 5X, as shown in FIG. 3b. As a result, the flow path from the working fluid source 2 to the first fluid pressure chamber 8a of the actuator 8 via the flow path 12a, the flow path 11b, and the flow path 11a is opened.

In this way, the working fluid is supplied to the first fluid pressure chamber 8a of the actuator 8 and the working fluid is discharged from the second fluid pressure chamber 8b, so that the actuator 8 can be extended.

The moving speed of the piston 8c when the actuator 8 contracts and extends is controlled by the opening area of the working fluid flow path in the meter-in valve 5 and the opening area of the working fluid flow path in the meter-out valve 6. As mentioned above, these opening areas can be adjusted by the first pilot pressure and the second pilot pressure. In this way, by adjusting the opening area of the working fluid flow path in the meter-in valve 5 and the opening area of the working fluid flow path in the meter-out valve 6 by controlling the first pilot pressure and the second pilot pressure, Meter-in control that adjusts the flow rate of the working fluid output from the working fluid source 2 to the actuator 8 via the meter-in valve 5 when the actuator 8 is operated, and working fluid discharged from the actuator 8 to the tank 3 via the meter-out valve 6. Meter-out control is performed to adjust the flow rate.

Next, with reference to FIG. 4, an actuator control device 101 according to another embodiment of the present invention will be described. An actuator control device 101 according to another embodiment of the present invention differs from the actuator control device 1 in that it has two working fluid sources and the supply of working fluid from the two working fluid sources is controlled by a meter-in valve 105. It's different. Among the components of the actuator control device 101 shown in FIG. 4, those that are the same or similar to the components of the actuator control device 1 shown in FIG. 1 are given the same or similar reference numerals as in FIG. , detailed description of these components will be omitted.

As shown, the actuator control device 101 includes a working fluid source 102 in addition to the working fluid source 2 . The working fluid source 102 is connected to the meter-in valve 105 by a flow path 112a. A check valve 104 for maintaining negative pressure is provided in the flow path 112a.

The meter-in valve 105 is provided between the actuator 8 and the working fluid source 2 and 102 . The working fluid source 2 and the working fluid source 102 are arranged in parallel to the meter-in valve 105.

The meter-in valve 105 has a meter-in valve spool, and by displacing the meter-in valve spool by pilot pressure from the electromagnetic proportional valve 31 or the second electromagnetic proportional valve 32, the meter-in valve 105 and the actuator 8 are connected. The fluid path is configured to be switchable. Specifically, the meter-in valve 105 has a first communication position 105X that outputs the working fluid from the working fluid source 2 to the first fluid pressure chamber 8a through the flow path 11b, the flow path 11a, and the first port P1; A cutoff position 105Y that cuts off the output of the working fluid to each fluid pressure chamber 8a, 8b, and at least one of the working fluid from the working fluid source 2 and the working fluid source 102 is connected to the flow path 11e, the flow path 11d, and the second port. It is switched to one of the second communication positions 105Z for outputting to the second fluid pressure chamber 8b via P2. In the illustrated embodiment, the meter-in valve 105 is switched to the first communicating position 105X by the first pilot pressure from the first proportional electromagnetic valve 31 and to the second communicating position 105X by the second pilot pressure from the second proportional electromagnetic valve 32. Can be switched to 105Z. The second communication position 105Z is a second single communication position 105Z1 that outputs the working fluid of only the working fluid source 2 out of the working fluid sources 2 and 102 arranged in parallel to the second fluid pressure chamber 8b, and the working fluid and a second multiple communication position 105Z2 that outputs the working fluid from both the source 2 and the working fluid source 102 to the second fluid pressure chamber 8b. The meter-in valve 105 is switched to the second single communication position 105Z1 when the second pilot pressure is lower than a predetermined reference pressure, and is switched to the second double communication position 105Z2 when the second pilot pressure is higher than the predetermined reference pressure. may be switched to

In the illustrated embodiment, the meter-in valve 105 may be configured to output working fluid from both the working fluid source 2 and the working fluid source 102 to the first fluid pressure chamber 8a. For example, the first communication position 105X is a first single communication position and an operation position where the working fluid of only the working fluid source 2 out of the working fluid sources 2 and 102 arranged in parallel is output to the first fluid pressure chamber 8a. and a first multiple communication position where working fluid from both the fluid source 2 and the working fluid source 102 is output to the first fluid pressure chamber 8a. The meter-in valve 105 is switched to the first single communication position 105 when the first pilot pressure is lower than a predetermined reference pressure, and to the first double communication position when the first pilot pressure is higher than the predetermined reference pressure. May be switched.

The actuator control device 101 operates generally in the same manner as the actuator control device 1. When switching the meter-in valve 5 to the third communication position 105Z2, the controller 10 excites the second electromagnetic proportional valve 32 so that the second pilot pressure becomes equal to or higher than a predetermined reference value.

Next, the effects of the above embodiment will be explained. In the actuator control devices 1 and 101 according to the above embodiments, the switching mechanism 20 selectively controls the first pilot pressure output from the first electromagnetic proportional valve 31 and the second pilot pressure output from the second electromagnetic proportional valve 32. The flow path between the actuator 8 and the meter-in valve 5 and meter-out valve 6 can be switched by outputting to the meter-in valve 5 and meter-out valve 6. Thereby, according to the actuator control device 1, meter-in control and meter-out control of the actuator 8 can be realized by controlling the two pilot pressures, the first pilot pressure and the second pilot pressure. More specifically, in the above embodiment, the meter-in control of the actuator 8 is performed by two spools (the meter-in valve spool of the meter-in valve 5 and the meter-out valve spool of the meter-out valve 6) and the two electromagnetic pilot valves 31 and 32. and meter-out control can be realized. Therefore, according to the actuator control devices 1 and 101 according to the above embodiments, the conventional actuator control devices 1 and 101 perform meter-in control and meter-out control using four spools (two meter-in valve spools and two meter-out valve spools) and four electromagnetic proportional valves. Compared to the IMV type actuator control device, meter-in control and meter-out control can be performed with a simpler configuration.

According to the above embodiment, the switching mechanism 20 can be realized by the first selector valve 21 and the second selector valve 22. Both the first selector valve 21 and the second selector valve 22 can be two-position valves having a simple configuration that can be switched between two positions. Therefore, according to the above embodiment, the switching mechanism 20 for the actuator control device can be realized with a simple configuration.

According to the above embodiment, when the second pilot pressure is not output from the second electromagnetic proportional valve 32 to the switching mechanism 20, the first electromagnetic proportional valve 31 is controlled to supply the first pilot pressure to the switching mechanism 20. By outputting the output, the first selector valve 21 is switched to the first position 21X, and the second selector valve 22 is switched to the second position 22X. Thereby, switching in the switching mechanism 20 can be performed through control of the first electromagnetic proportional valve 31.

According to the above embodiment, when the first pilot pressure is not outputted from the first electromagnetic proportional valve 31 to the switching mechanism 20, the second electromagnetic proportional valve 32 is controlled to supply the second pilot pressure to the switching mechanism 20. By outputting the output, the first selector valve 21 is switched to the second position 21Y, and the second selector valve 22 is switched to the fourth position 22Y. Thereby, switching in the switching mechanism 20 can be executed through control of the second electromagnetic proportional valve 31.

According to the above embodiment, the working fluid can be outputted to the actuator 8 at a flow rate according to the first pilot pressure or the second pilot pressure, so that the first electromagnetic proportional valve 31 and the second electromagnetic proportional valve 32 Meter-in control can be performed through control of the two electromagnetic proportional valves.

According to the above embodiment, the working fluid can be discharged from the actuator 8 at a flow rate depending on the first pilot pressure or the second pilot pressure, so that the first solenoid proportional valve 31 and the second solenoid proportional valve 32 Meter-out control can be performed through control of two electromagnetic proportional valves.

According to one embodiment described above, the working fluid from the two working fluid sources 2, 102 can be utilized independently to drive the actuator 8.

The dimensions, materials, and arrangement of each component described herein are not limited to those explicitly described in the embodiments, and each component may be any number that may fall within the scope of the present invention. dimensions, materials, and arrangements. Further, components not explicitly described in this specification can be added to the described embodiments, or some of the components described in each embodiment can be omitted.

The meter-in valve 5, the meter-out valve 6, the first selector valve 21, the second selector valve 22, the first electromagnetic proportional valve 31, and the second electromagnetic proportional valve 32 are provided in a single manifold (or valve body). It may also be provided dispersedly in a plurality of manifolds. When these valves are distributed and provided in a plurality of manifolds, the actuator control device 1, 101 is produced by assembling the plurality of manifolds.

1, 101 Actuator control device 2, 102 Working fluid source 3 Tank 4, 104 Check valve 5, 105 Meter-in valve 6 Meter-out valve 8 Actuator 8a First fluid pressure chamber 8b Second fluid pressure chamber 10 Controller 20 Switching mechanism 21 First Selector valve 22 Second selector valve 31 First electromagnetic proportional valve 32 Second electromagnetic proportional valve

Claims (10)

a meter-out valve that discharges working fluid from one fluid pressure chamber of the actuator to a tank using a first pilot pressure or a second pilot pressure;
a meter-in valve that outputs the working fluid from the working fluid source to the other fluid pressure chamber of the actuator using the first pilot pressure or the second pilot pressure;
Switching to output one of the first pilot pressure and the second pilot pressure to the meter-out valve and the other to the meter-in valve based on at least one of the first pilot pressure and the second pilot pressure. a switching mechanism,
An actuator control device comprising: The switching mechanism is switched by movement of the meter-out valve.
The actuator control device according to claim 1. The switching mechanism includes a first selector valve that can be switched to a first position where the first pilot pressure is output to the meter-out valve or a second position where the first pilot pressure is output to the meter-in valve; and the second pilot valve. a second selector valve that can be switched to a third position that outputs the pressure to the meter-in valve or a fourth position that outputs the second pilot pressure to the meter-out valve;
The actuator control device according to claim 1 or 2. The switching mechanism switches the first selector valve to the first position in response to receiving the first pilot pressure when the second pilot pressure is not supplied. Switch to 3 positions,
The actuator control device according to claim 3. The switching mechanism switches the first selector valve to the second position in response to receiving the second pilot pressure when the first pilot pressure is not supplied. Switch to 4 positions,
The actuator control device according to claim 3. The meter-in valve outputs the working fluid to the actuator according to the first pilot pressure or the second pilot pressure.
The actuator according to any one of claims 1 to 5. the meter-out valve discharges the working fluid from the actuator in response to the first pilot pressure or the second pilot pressure;
The actuator according to any one of claims 1 to 6. The meter-in valve is provided between the actuator and a first working fluid source and a second working fluid source.
The actuator control device according to any one of claims 1 to 7. The meter-in valve has a position where the working fluid is output to the actuator from either one of the first working fluid source and the second working fluid source, and a position where the working fluid is output from both the first working fluid source and the second working fluid source. switchable between a position where the working fluid is output to the actuator;
The actuator control device according to claim 8. a first electromagnetic proportional valve;
a second electromagnetic proportional valve;
A first pilot pressure outputted from the first electromagnetic proportional valve switches the actuator to a first discharge position in which working fluid is discharged from one fluid pressure chamber to a tank, and a second pilot pressure outputted from the second electromagnetic proportional valve a meter-out valve that is switched by pilot pressure to a second discharge position for discharging working fluid from the other fluid pressure chamber of the actuator to a tank;
The first pilot pressure switches the working fluid from the working fluid source to the first fluid pressure chamber of the actuator, and the second pilot pressure switches the working fluid from the working fluid source to the other fluid pressure chamber of the actuator. a meter-in valve that is switched to a second communication position for supplying fluid to the fluid pressure chamber;
a first selector valve that is switched to a first position for supplying the first pilot pressure to the meter-out valve or a second position for supplying the first pilot pressure to the meter-in valve; and a first selector valve that supplies the second pilot pressure to the meter-in valve. a second selector valve that can be switched to a third position for supplying the second pilot pressure or a fourth position for supplying the second pilot pressure to the meter-out valve, the first selector valve being switched from the first position to the first position by movement of the meter-out valve; a switching mechanism that switches the second selector valve to the second position or switches the second selector valve from the fourth position to the third position;
An actuator control device comprising: