CN113048105A

CN113048105A - Actuator control device

Info

Publication number: CN113048105A
Application number: CN202011344243.9A
Authority: CN
Inventors: 岩崎仁
Original assignee: Nabtesco Corp
Current assignee: Nabtesco Corp
Priority date: 2019-12-26
Filing date: 2020-11-26
Publication date: 2021-06-29
Also published as: JP7370854B2; KR20210083162A; JP2021105421A

Abstract

The invention provides an actuator control device. An actuator control device according to an embodiment of the present invention includes: an outlet throttle valve that discharges the working fluid from a 1 st fluid pressure chamber of the actuator to the tank using a 1 st pilot pressure or a 2 nd pilot pressure; an inlet throttle valve that outputs the working fluid from a working fluid source to a 2 nd fluid pressure chamber of the actuator using the 1 st pilot pressure or the 2 nd pilot pressure; and a switching mechanism that switches based on at least one of the 1 st pilot pressure and the 2 nd pilot pressure to output one of the 1 st pilot pressure and the 2 nd pilot pressure to the outlet throttle and output the other of the 1 st pilot pressure and the 2 nd pilot pressure to the inlet throttle.

Description

Actuator control device

Technical Field

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

Background

Actuators driven by a working fluid are used in various machines such as construction machines. The actuator driven by the working fluid is a fluid pressure cylinder such as a hydraulic cylinder. As the fluid pressure cylinders provided in the construction machine, 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 that controls operation of an actuator includes a control valve provided between the actuator and a working fluid source and a tank. The control valve includes a single spool that is movable in the axial direction. An in-port/out-port throttle control is performed that adjusts the flow rate of the working fluid supplied to the fluid pressure cylinder and the flow rate of the working fluid discharged from the fluid pressure cylinder in accordance with the position of the spool in the axial direction. A conventional actuator control device that performs inlet/outlet throttle control using a control valve having a single spool is disclosed in, for example, japanese patent application laid-open No. 2003-269411.

In order to properly perform meter-in/meter-out control using a single spool, it is necessary to provide a groove (also referred to as a "throttle portion") extending in the circumferential direction around the axis at an appropriate position on the outer surface of the spool. The position and size of the throttle portion of the spool are adjusted using test data obtained by actually operating the actuator to be controlled using a test product of the spool. It is often necessary to make multiple trials.

As described above, in an actuator control device that performs meter-in/meter-out control using a single spool, there is a problem in that it is difficult to provide an appropriate throttle portion in the spool. Therefore, an actuator control device of an IMV (Independent Metering Valve) system has been proposed, which performs meter-in control and meter-out control by independently controlling the positions of a plurality of spools. A conventional IMV actuator control device is disclosed in japanese patent application laid-open No. 2001-003905.

Documents of the prior art

Patent document

Patent document 1: japanese patent laid-open publication No. 2003-269411

Patent document 2: japanese patent laid-open No. 2001-003905

Disclosure of Invention

Problems to be solved by the invention

A conventional actuator control device using an IMV includes: two spools for meter-in control, two spools for meter-out control, and 4 solenoid proportional valves for independently controlling the positions of the 4 spools. That is, the conventional IMV actuator control device includes 4 spools and 4 electromagnetic proportional valves.

The present disclosure aims to alleviate or solve at least some of the above-described problems of the related art. Specifically, one of the objects of the present disclosure is to realize an actuator control device that performs meter-in/meter-out control with a simpler structure. Objects of the present disclosure other than those described above will become apparent from all descriptions of the present specification.

Means for solving the problems

An actuator control device according to an aspect of the present invention includes: an outlet throttle valve that discharges the working fluid from a 1 st fluid pressure chamber of the actuator to the tank using a 1 st pilot pressure or a 2 nd pilot pressure; an inlet throttle valve that outputs the working fluid from a working fluid source to a 2 nd fluid pressure chamber of the actuator using the 1 st pilot pressure or the 2 nd pilot pressure; and a switching mechanism that switches based on at least one of the 1 st pilot pressure and the 2 nd pilot pressure to output one of the 1 st pilot pressure and the 2 nd pilot pressure to the outlet throttle and output the other of the 1 st pilot pressure and the 2 nd pilot pressure to the inlet throttle.

In one aspect of the present invention, the switching mechanism switches by movement of the outlet throttle valve.

In one aspect of the present invention, the switching mechanism includes: a 1 st selector valve that can be switched between a 1 st position at which the 1 st pilot pressure is output to the outlet throttle valve and a 2 nd position at which the 1 st pilot pressure is output to the inlet throttle valve; and a 2 nd selector valve that can be switched between a 3 rd position at which the 2 nd pilot pressure is output to the inlet throttle valve and a 4 th position at which the 2 nd pilot pressure is output to the outlet throttle valve.

In one aspect of the present invention, the switching mechanism switches the 1 st selector valve to the 1 st position and the 2 nd selector valve to the 3 rd position in response to the 1 st pilot pressure being received when the 2 nd pilot pressure is not supplied.

In one aspect of the present invention, the switching mechanism switches the 1 st selector valve to the 2 nd position and the 2 nd selector valve to the 4 th position in response to the 2 nd pilot pressure being received when the 1 st pilot pressure is not supplied.

In one aspect of the present invention, the throttle inlet outputs the working fluid to the actuator in accordance with the 1 st pilot pressure or the 2 nd pilot pressure.

In one aspect of the present invention, the outlet throttle discharges the working fluid from the actuator in accordance with the 1 st pilot pressure or the 2 nd pilot pressure.

In one aspect of the present invention, the throttle inlet is disposed between the actuator and the 1 st and 2 nd sources of working fluid.

In one aspect of the present invention, the throttle inlet valve is switched between: a position at which the working fluid is output to the actuator from either of the 1 st and 2 nd sources of working fluid; a position to output the working fluid to the actuator from both the 1 st and 2 nd sources of working fluid.

ADVANTAGEOUS EFFECTS OF INVENTION

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

Drawings

Fig. 1 is a diagram schematically showing an actuator control device according to an embodiment of the present invention.

Fig. 2a is a diagram for explaining an operation of contracting the actuator in the actuator control device of fig. 1. In fig. 2a, the outlet throttle 6 communicates with the 1 st fluid pressure chamber 8a of the actuator 8.

Fig. 2b is a diagram for explaining an operation of contracting the actuator in the actuator control device of fig. 1. In fig. 2b, the outlet throttle 6 is in communication with the 1 st fluid pressure chamber 8a of the actuator 8 and the inlet throttle 5 is in communication with the 2 nd fluid pressure chamber 8b of the actuator 8.

Fig. 3a is a diagram for explaining an operation of extending the actuator with respect to the actuator control device of fig. 1. Is a diagram schematically showing the actuator control device of fig. 1. In fig. 3a, the outlet throttle 6 communicates with the 2 nd fluid pressure chamber 8b of the actuator 8.

Fig. 3b is a diagram for explaining an operation of extending the actuator in the actuator control device of fig. 1. In fig. 3b, the outlet throttle 6 is in communication with the 2 nd fluid pressure chamber 8b of the actuator 8 and the inlet throttle 5 is in communication with the 1 st fluid pressure chamber 8a of the actuator 8.

Fig. 4 is a diagram schematically showing an actuator control device according to another embodiment of the present invention.

Description of the reference numerals

1. 101, an actuator control device; 2. 102, a working fluid source; 3. a tank; 4. 104, a check valve; 5. 105, an inlet throttle valve; 6. an outlet throttle valve; 8. an actuator; 8a, 1 st fluid pressure chamber; 8b, 2 nd fluid pressure chamber; 10. a controller; 20. a switching mechanism; 21. 1 st selector valve; 22. a 2 nd selector valve; 31. 1 st electromagnetic proportional valve; 32. 2 nd electromagnetic proportional valve.

Detailed Description

Hereinafter, various embodiments of the present invention will be described with reference to the drawings as appropriate. In addition, the same reference numerals are given to the constituent elements common to the plurality of drawings. The following is to be noted: for convenience of explanation, the drawings are not necessarily drawn to precise scale. In each drawing, some constituent elements may be omitted for convenience of description.

The present invention can be applied to an actuator control device that controls the operation of a fluid pressure actuator that is divided into at least two fluid pressure chambers. An actuator control device according to an embodiment of the present invention will be described with reference to fig. 1.

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 a member to be driven by operating the actuator 8. The member driven by the actuator 8 is, for example, a boom, an arm, and a bucket of the construction machine, and a movable member of the construction machine other than these. The actuator control device 1 can be applied to various machines other than the construction machine.

In the illustrated embodiment, the actuator control device 1 includes: a working fluid source 2 for supplying working fluid to the actuator 8, a tank 3 for storing working fluid discharged from the actuator 8, a check valve 4, an inlet throttle 5, an outlet throttle 6, a controller 10, a switching mechanism 20, a 1 st electromagnetic proportional valve 31, and a 2 nd electromagnetic proportional valve 32.

The working fluid source 2 ejects the working fluid. The working fluid discharged from the working fluid source 2 is output to the actuator 8 via the inlet throttle 5. The working fluid source 2 is, for example, a variable displacement pump capable of adjusting the amount of the working fluid to be discharged. A check valve 4 for maintaining a negative pressure is provided between the working fluid source 2 and the inlet throttle 5.

The actuator 8 is, for example, a fluid pressure type actuator driven by a working fluid. The actuator 8 may be a hydraulic actuator driven by hydraulic oil. The actuator 8 may be an air pressure type actuator that operates using compressed air or any fluid pressure type actuator that operates using a working fluid other than these. The actuator control device 1 may include a plurality of actuators.

The actuator 8 is divided into a 1 st fluid pressure chamber 8a and a 2 nd fluid pressure chamber 8b by a piston 8c provided inside a hollow cylinder. The cylinder of the actuator 8 is configured such that one side in the longitudinal direction thereof is open and the other side is closed. A piston rod 8d is connected to the piston 8 c. A part of the piston rod 8d protrudes outside the cylinder. The distal end of the piston rod 8d is connected to a movable member such as a boom, an arm, and a bucket. The actuator 8 may be provided with a position sensor for detecting the position of the piston 8 c. The position sensor is, for example, a Linear Variable Differential Transformer (LVDT).

The controller 10 includes: a processor that performs various arithmetic processes; a memory storing various programs and various data; and a device interface for connecting with various sensors and other devices. The controller 10 outputs control pulses to the electromagnetic

proportional valves

31 and 32, and can adjust the flow rates of the pilot pressures output from the electromagnetic

proportional valves

31 and 32. When the actuator control device 1 is mounted on a construction machine, the controller 10 can receive a control signal associated with an operation of an operation lever of the construction machine and control the electromagnetic proportional valve 31 and the electromagnetic proportional valve 32 based on the control signal.

The 1 st and 2 nd electromagnetic

proportional valves

31 and 32 are connected to a pilot pressure source, not shown. The 1 st electromagnetic proportional valve 31 is connected to the switching mechanism 20 through a flow path 13a, and the 2 nd electromagnetic proportional valve 32 is connected to the switching mechanism 20 through a flow path 13 d. The 1 st electromagnetic proportional valve 31 includes a solenoid coil, a drive rod driven by the solenoid coil to move in the axial direction, and a pilot spool moved in the axial direction by thrust received from the drive rod. The 1 st and 2 nd electromagnetic

proportional valves

31 and 32 may be known electromagnetic proportional valves. The input current to the solenoid coil is determined based on the control pulse from the controller 10. The 1 st electromagnetic proportional valve 31 is provided with a flow path that connects the pilot pressure source and the flow path 13 a. The opening area of the flow path changes depending on the position of the pilot spool in the axial direction. The 1 st electromagnetic proportional valve 31 can output the pilot fluid from the pilot pressure source to the flow path 13a at a flow rate according to an opening area that changes according to the position of the pilot spool in the axial direction. The 2 nd electromagnetic proportional valve 32 includes the same components as those of the 1 st electromagnetic proportional valve 31. The 2 nd electromagnetic proportional valve 32 can supply the pilot fluid from the pilot pressure source to the flow path 13d at a flow rate according to an opening area that changes according to the position of the pilot spool in the axial direction. In this specification, the pilot fluid or the pilot pressure output from the 1 st electromagnetic proportional valve 31 may be referred to as a 1 st pilot pressure, and the pilot fluid or the pilot pressure output from the 2 nd electromagnetic proportional valve 32 may be referred to as a 2 nd pilot pressure.

The throttle inlet valve 5 is disposed between the actuator 8 and the working fluid source 2. The 1 st fluid pressure chamber 8a of the actuator 8 is connected to the inlet throttle valve 5 via the 1 st port P1, the flow path 11a, and the flow path 11 b. The 2 nd fluid pressure chamber 8b of the actuator 8 is connected to the inlet throttle valve 5 via a port P2, a flow path 11d, and a flow path 11 e. The inlet throttle 5 is also connected to the switching mechanism 20 to receive the supply of the pilot pressure. Specifically, the inlet throttle valve 5 is connected to the switching mechanism 20 through the

flow paths

13b and 13 e. The inlet throttle 5 has at least one pilot pressure receiving chamber. In accordance with the switching of the switching mechanism 20, the pilot pressure is output from the 1 st or 2 nd electromagnetic

proportional valve

31 or 32 to the at least one pilot pressure receiving chamber of the inlet throttle 5.

The inlet throttle 5 has a spool received into the internal space of the manifold. The spool of the meter-in valve 5 is sometimes referred to as a meter-in spool. The inlet throttle 5 is configured to be able to switch a flow path connecting the inlet throttle 5 and the actuator 8 by axially displacing an inlet throttle spool by a pilot pressure from the electromagnetic proportional valve 31 or the 2 nd electromagnetic proportional valve 32. Specifically, the inlet throttle valve 5 can be switched to any one of the following positions: a 1 st communication position 5X at which the working fluid from the working fluid source 2 is output to the 1 st fluid pressure chamber 8a via the flow path 11b, the flow path 11a, and the 1 st port P1; a blocking position 5Y at which the output of the working fluid to the

fluid pressure chambers

8a and 8b is blocked; and a 2 nd communication position 5Z at which the working fluid from the working fluid source 2 is output to the 2 nd fluid pressure chamber 8b via the flow path 11e, the flow path 11d, and the 2 nd port P2. In the illustrated embodiment, the inlet throttle valve 5 is switched to the 1 st communication position 5X by the pilot pressure from the 1 st electromagnetic proportional valve 31, and is switched to the 2 nd communication position 5Z by the pilot pressure from the 2 nd electromagnetic proportional valve 32.

The inlet throttle valve 5 is provided with a flow path connecting the flow path 12a and the flow path 11b or the flow path 12a and the flow path 11e, and the flow path 12a is connected to the working fluid source 2. When the inlet throttle valve 5 is switched to the 1 st communication position 5X, the flow passage of the inlet throttle valve 5 is connected to the flow passage 11b to open the flow passage from the working fluid source 2 to the 1 st fluid pressure chamber 8a, and the working fluid is output to the 1 st fluid pressure chamber 8a through the flow passage. When the inlet throttle valve 5 is switched to the 2 nd communication position 5Z, the flow passage of the inlet throttle valve 5 is connected to the flow passage 11e to open the flow passage from the working fluid source 2 to the 2 nd fluid pressure chamber 8b, and the working fluid is output to the 2 nd fluid pressure chamber 8b through the flow passage. The opening area of the flow path through which the working fluid in the meter-in valve 5 passes varies depending on the position in the axial direction of the meter-in valve spool. The position of the throttle inlet spool in the axial direction is adjusted by the 1 st pilot pressure or the 2 nd pilot pressure output to the pilot pressure receiving chamber of the throttle inlet 5. In this way, the meter-in valve 5 can selectively output the working fluid from the working fluid source 2 to the 1 st fluid pressure chamber 8a or the 2 nd fluid pressure chamber 8b at a flow rate corresponding to the opening area of the flow passage in the meter-in valve 5, which varies depending on the position of the meter-in spool in the axial direction. The opening area of the flow path through which the working fluid in the inlet throttle 5 passes is adjusted by adjusting the 1 st pilot pressure or the 2 nd pilot pressure to displace the position of the inlet throttle spool in the axial direction. In this way, the inlet throttle 5 can output the working fluid to the actuator 8 at a flow rate corresponding to the 1 st pilot pressure or the 2 nd pilot pressure.

An outlet throttle 6 is provided between the actuator 8 and the tank 3. The 1 st fluid pressure chamber 8a of the actuator 8 is connected to the outlet throttle 6 via the 1 st port P1, the flow path 11a, and the flow path 11 c. The 2 nd fluid pressure chamber 8b of the actuator 8 is connected to the outlet throttle 6 via the 2 nd port P2, the flow path 11d, and the flow path 11 f. The outlet throttle 6 is also connected to the switching mechanism 20 to receive the supply of the pilot pressure. Specifically, the outlet throttle valve 6 is connected to the switching mechanism 20 through the flow path 13c and the flow path 13 f. The outlet throttle 6 has at least one pilot pressure receiving chamber. In accordance with the switching of the switching mechanism 20, the pilot pressure is output from the 1 st or 2 nd electromagnetic

proportional valve

31 or 32 to the at least one pilot pressure receiving chamber of the outlet throttle 6.

The outlet throttle 6 has a spool housed in the internal space of the manifold, similarly to the inlet throttle 5. The spool of the outlet throttle 6 is sometimes referred to as an outlet throttle spool. The outlet throttle 6 is configured to be able to switch a flow path connecting the outlet throttle 6 and the actuator 8 by displacing an outlet throttle spool in the axial direction by a pilot pressure from the electromagnetic proportional valve 31 or the 2 nd electromagnetic proportional valve 32. Specifically, the outlet throttle valve 6 can be switched to any one of the following positions: a 1 st discharge position 6X at which the working fluid in the 1 st fluid pressure chamber 8a is discharged to the tank 3 via the 1 st port P1, the flow path 11a, the flow path 11c, and the flow path 12 b; a blocking position 6Y at which the discharge of the working fluid from the

fluid pressure chambers

8a and 8b is blocked; and a 2 nd discharge position 6Z at which the working fluid in the 2 nd fluid pressure chamber 8b is discharged to the tank 3 via the 2 nd port P2, the flow path 11d, the flow path 11f, and the flow path 12 b. In the illustrated embodiment, the outlet throttle 6 is switched to the 1 st discharge position 6X by the pilot pressure from the 1 st solenoid proportional valve 31, and is switched to the 2 nd discharge position 6Z by the pilot pressure from the 2 nd solenoid proportional valve 32.

The outlet throttle 6 is provided with a flow path connecting the flow path 12b and the flow path 11c or the flow path 12b and the flow path 11f, and the flow path 12b is connected to the tank 3. When the outlet throttle 6 is switched to the 1 st discharge position 6X, the flow path of the outlet throttle 6 is connected to the flow path 11c to open the flow path from the 1 st fluid pressure chamber 8a to the tank 3, and the working fluid is discharged from the 1 st fluid pressure chamber 8a through the flow path. When the outlet throttle 6 is switched to the 2 nd discharge position 6Z, the flow path of the outlet throttle 6 is connected to the flow path 11f to open the flow path from the 2 nd fluid pressure chamber 8b to the tank 3, and the working fluid is discharged from the 2 nd fluid pressure chamber 8b through the flow path. The opening area of the flow path through which the working fluid in the outlet throttle 6 passes varies depending on the position in the axial direction of the outlet throttle spool. The position of the outlet throttle spool in the axial direction is adjusted by the 1 st pilot pressure or the 2 nd pilot pressure output to the pilot pressure receiving chamber of the outlet throttle 6. In this way, the outlet throttle 6 can selectively discharge the working fluid from the working fluid source 2 at a flow rate corresponding to the opening area of the flow passage in the outlet throttle 6 that varies depending on the position of the outlet throttle spool in the axial direction. The opening area of the flow path through which the working fluid in the outlet throttle 6 passes is adjusted by adjusting the 1 st pilot pressure or the 2 nd pilot pressure to displace the position of the outlet throttle spool in the axial direction. In this manner, the outlet throttle 6 can discharge the working fluid from the actuator 8 at a flow rate corresponding to the 1 st pilot pressure or the 2 nd pilot pressure.

The switching mechanism 20 is configured to switch the flow paths between the 1 st and 2 nd electromagnetic

proportional valves

31 and 32 and the inlet throttle 5 and the outlet throttle 6, thereby outputting the 1 st pilot pressure from the 1 st electromagnetic proportional valve 31 to one of the inlet throttle 5 and the outlet throttle 6, and outputting the 2 nd pilot pressure from the 2 nd electromagnetic proportional valve 32 to the other of the inlet throttle 5 and the outlet throttle 6. Specifically, when the 1 st pilot pressure from the 1 st electromagnetic proportional valve 31 is output to the inlet throttle 5, the 2 nd pilot pressure from the 2 nd electromagnetic proportional valve 32 is output to the outlet throttle 6. On the contrary, when the 1 st pilot pressure from the 1 st electromagnetic proportional valve 31 is output to the outlet throttle 6, the 2 nd pilot pressure from the 2 nd electromagnetic proportional valve 32 is output to the inlet throttle 5, and the switching mechanism 20 controls the output throttle 6 to be higher than the first pilot pressure. As described in detail below, the flow path is switched by the switching mechanism 20 based on at least one of the 1 st pilot pressure, the 2 nd pilot pressure, and the movement of the outlet throttle 6 (the position of the outlet throttle 6).

The switching mechanism 20 includes a 1 st selector valve 21 and a 2 nd selector valve 22. The 1 st selector valve 21 is connected to the 1 st electromagnetic proportional valve 31 through a flow path 13a, connected to the inlet throttle valve 5 through a flow path 13b, and connected to the outlet throttle valve 6 through a flow path 13 c. The 1 st selector valve 21 is switched between either the 1 st position 21X, at which the 1 st pilot pressure from the 1 st electromagnetic proportional valve 31 is output to the outlet throttle 6, or the 2 nd position 21Y, at which the 1 st pilot pressure from the 1 st electromagnetic proportional valve 31 is output to the inlet throttle 5. The 1 st selector valve 21 itself and the 2 nd selector valve 22 themselves may also be known selector valves.

The 2 nd selector valve 22 is connected to the 2 nd electromagnetic proportional valve 32 through a flow path 13d, to the inlet throttle valve 5 through a flow path 13e, and to the outlet throttle valve 6 through a flow path 13 f. The 2 nd selector valve 22 is switched to either the 3 rd position 22X, at which the 2 nd pilot pressure from the 2 nd electromagnetic proportional valve 32 is output to the inlet throttle 5, or the 4 th position 22Y, at which the 2 nd pilot pressure from the 2 nd electromagnetic proportional valve 32 is output to the outlet throttle 6.

When the 1 st solenoid proportional valve 31 is excited while the 2 nd solenoid proportional valve 32 is not excited, the 1 st selector valve 21 receives the 1 st pilot pressure from the 1 st solenoid proportional valve 31 and is switched to the 1 st position 21X. When the 2 nd electromagnetic proportional valve 32 is not excited, the 2 nd pilot pressure is not output from the 2 nd electromagnetic proportional valve 32 to the switching mechanism 20. That is, when the 1 st pilot pressure is output from the 1 st solenoid proportional valve 31 while the 2 nd pilot pressure is not output from the 2 nd solenoid proportional valve 32, the 1 st selector valve 21 is switched to the 1 st position 21X. The 1 st selector valve 21 has a push pin 21a connected to the outlet throttle valve 6. When the outlet throttle 6 is switched to the 2 nd discharge position 6Z while the 1 st pilot pressure is not being output to the 1 st selector valve 21, the push pin 21a is pushed into the 1 st selector valve 21. When the push pin 21a is pushed inward of the 1 st selector valve 21, the 1 st selector valve 21 is switched to the 2 nd position 21Y. Even if the 2 nd pilot pressure is output from the 2 nd electromagnetic proportional valve 32 to the switching mechanism 20 while the 1 st pilot pressure is output to the 1 st selector valve 21, the 1 st selector valve 21 is in the 1 st position 21X and the 2 nd selector valve 22 is in the 3 rd position 22X. That is, the 1 st selector valve 21 is locked in the 1 st position 21X and the 2 nd selector valve 22 is locked in the 3 rd position 22X by the 1 st pilot pressure from the 1 st electromagnetic proportional valve 31.

When the 1 st electromagnetic proportional valve 31 is not excited and the 2 nd electromagnetic proportional valve 32 is excited, the 2 nd selector valve 22 receives the 2 nd pilot pressure from the 2 nd electromagnetic proportional valve 32 and is switched to the 4 th position 22Y. When the 1 st electromagnetic proportional valve 31 is not excited, the 1 st pilot pressure is not output from the 1 st electromagnetic proportional valve 31 to the switching mechanism 20. That is, when the 1 st pilot pressure is not output from the 1 st electromagnetic proportional valve 31 and the 2 nd pilot pressure is output from the 2 nd electromagnetic proportional valve 32, the 2 nd selector valve 22 is switched to the 4 th position 22Y. The 2 nd selector valve 22 has a push pin 22a connected to the outlet throttle valve 6. When the outlet throttle 6 is switched to the 1 st discharge position 6X while the 2 nd pilot pressure is not being output to the 2 nd selector valve 22, the push pin 22a is pushed into the inside of the 2 nd selector valve 22. When the push pin 22a is pushed inward of the 2 nd selector valve 22, the 2 nd selector valve 22 is switched to the 3 rd position 22X. Even if the 1 st pilot pressure is output from the 1 st electromagnetic proportional valve 31 to the switching mechanism 20 while the 2 nd pilot pressure is output to the 2 nd selector valve 22, the 2 nd selector valve 22 is in the 4 th position 22Y and the 1 st selector valve 21 is in the 2 nd position 21Y. That is, the 2 nd selector valve 22 is locked in the 4 th position 22Y and the 1 st selector valve 21 is locked in the 2 nd position 21Y by the 2 nd pilot pressure from the 2 nd electromagnetic proportional valve 32.

Next, the operation of the actuator control device 1 will be described with reference to fig. 2a, 2b, 3a, and 3 b. Imagine that: at the start of operation, since neither the 1 st nor the 2 nd electromagnetic

proportional valves

31, 32 are excited, the pilot pressure is not output from either the 1 st or the 2 nd electromagnetic

proportional valves

31, 32. In this case, as shown in fig. 1, the inlet throttle 5 is located at the blocking position 5Y, and the outlet throttle 6 is located at the blocking position 6Y. In addition, the 1 st selector valve 21 and the 2 nd selector valve 22 are not locked.

The operation of contracting the actuator 8 will be described with reference to fig. 2a and 2 b. When contracting the actuator 8, the controller 10 excites the 1 st electromagnetic proportional valve 31. As a result, the 1 st electromagnetic proportional valve 31 is opened, and the 1 st pilot pressure is output from the 1 st electromagnetic proportional valve 31 to the 1 st selector valve 21 of the switching mechanism 20. The 1 st selector valve 21 is switched to the 1 st position 21X by the 1 st pilot pressure.

The 1 st selector valve 21 is switched to the 1 st position 21X, thereby outputting the 1 st pilot pressure to the outlet throttle 6. As shown in fig. 2a, the 1 st pilot pressure switches the outlet throttle 6 to the 1 st discharge position 6X. Thereby, a flow path from the 1 st 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. In addition, since the outlet throttle valve 6 is switched to the 1 st discharge position 6X, the push pin 22a is pushed into the inside of the 2 nd selector valve 22, and thereby the 2 nd selector valve 22 is switched to the 3 rd position 22X.

Next, the controller 10 excites the 2 nd electromagnetic proportional valve 32 and opens the 2 nd electromagnetic proportional valve 32 while keeping the 1 st electromagnetic proportional valve 31 excited. Since the 2 nd selector valve 22 is switched to the 3 rd position 22X, the 2 nd pilot pressure from the 2 nd electromagnetic proportional valve 32 is output to the inlet throttle 5. As shown in fig. 2b, the inlet throttle valve 5 is switched to the 2 nd communication position 5Z by the 2 nd pilot pressure from the 2 nd electromagnetic proportional valve 32. Thereby, a flow path from the working fluid source 2 to the 2 nd 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 2 nd fluid pressure chamber 8b of the actuator 8 and discharged from the 1 st fluid pressure chamber 8a, and therefore, the actuator 8 can be contracted.

Next, an operation of extending the actuator 8 will be described with reference to fig. 3a and 3 b. When the actuator 8 is extended while both the 1 st and 2 nd electromagnetic

proportional valves

31 and 32 are excited as shown in fig. 2b, the controller 10 stops the excitation of the 1 st and 2 nd electromagnetic

proportional valves

31 and 32 and releases the lock of the 1 st and 2

nd selector valves

21 and 22. The controller 10 then excites the 2 nd electromagnetic proportional valve 32 and opens the 2 nd electromagnetic proportional valve 32. Thereby, the 2 nd pilot pressure is output from the 2 nd electromagnetic proportional valve 32 to the 2 nd selector valve 22 of the switching mechanism 20. The 2 nd selector valve 22 is switched to the 4 th position 22Y by the 2 nd pilot pressure.

The 2 nd selector valve 22 is switched to the 4 th position 22Y, thereby outputting the 2 nd pilot pressure to the outlet throttle 6. As shown in fig. 3a, the 2 nd pilot pressure switches the outlet throttle 6 to the 2 nd discharge position 6Z. Thereby, a flow path from the 2 nd 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. In addition, since the outlet throttle valve 6 is switched to the 2 nd discharge position 6Z, the push pin 21a is pushed into the 1 st selector valve 21, and thereby the 1 st selector valve 21 is switched to the 2 nd position 21Y.

Next, the controller 10 excites the 1 st electromagnetic proportional valve 31 and opens the 1 st electromagnetic proportional valve 31 while keeping the 2 nd electromagnetic proportional valve 32 excited. Since the 1 st selector valve 21 is switched to the 2 nd position 21Y, the 1 st pilot pressure from the 1 st electromagnetic proportional valve 31 is output to the inlet throttle 5. As shown in fig. 3b, the 1 st pilot pressure from the 1 st electromagnetic proportional valve 31 is used to switch the inlet throttle 5 to the 1 st communication position 5X. Thereby, a flow path from the working fluid source 2 to the 1 st 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 1 st fluid pressure chamber 8a of the actuator 8 and discharged from the 2 nd fluid pressure chamber 8b, and therefore, the actuator 8 can be extended.

The moving speed of the piston 8c at the time of contraction and expansion of the actuator 8 is controlled by the opening area of the flow path of the working fluid in the inlet throttle 5 and the opening area of the flow path of the working fluid in the outlet throttle 6. As described above, these opening areas can be adjusted using the 1 st pilot pressure and the 2 nd pilot pressure. In this way, by adjusting the opening area of the flow path of the working fluid in the meter-in valve 5 and the opening area of the flow path of the working fluid in the meter-out valve 6 by the control of the 1 st pilot pressure and the 2 nd pilot pressure, the meter-in control for adjusting the flow rate of the working fluid output from the working fluid source 2 to the actuator 8 via the meter-in valve 5 and the meter-out control for adjusting the flow rate of the working fluid discharged from the actuator 8 to the tank 3 via the meter-out valve 6 are performed at the time of the operation of the actuator 8.

Next, an actuator control device 101 according to another embodiment of the present invention will be described with reference to fig. 4. The actuator control device 101 of another embodiment of the present invention is different from the actuator control device 1 in that there are two working fluid sources and in that the supply of the working fluid from the two working fluid sources is controlled by the inlet throttle valve 105. Of the components of the actuator control device 101 shown in fig. 4, those components that are the same as or similar to those of the actuator control device 1 shown in fig. 1 are given the same reference numerals as or similar to those of fig. 1, and detailed description thereof will be omitted.

As shown in the figure, 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 inlet throttle valve 105 through a flow path 112 a. The flow path 112a is provided with a check valve 104 for maintaining a negative pressure.

An inlet throttle 105 is provided between the actuator 8 and the working

fluid source

2 and 102. The source of working fluid 2 and the source of working fluid 102 are arranged in parallel relative to the inlet throttle valve 105.

The inlet throttle 105 has an inlet throttle spool, and is configured to be able to switch a path of the working fluid connecting the inlet throttle 105 and the actuator 8 by displacing the inlet throttle spool by a pilot pressure from the electromagnetic proportional valve 31 or the 2 nd electromagnetic proportional valve 32. Specifically, the inlet throttle valve 105 can be switched to any one of the following positions: a 1 st communication position 105X at which the working fluid from the working fluid source 2 is output to the 1 st fluid pressure chamber 8a via the flow path 11b, the flow path 11a, and the 1 st port P1; a blocking position 105Y at which the output of the working fluid to the

fluid pressure chambers

8a and 8b is blocked; and a 2 nd communication position 105Z at which at least one of the working fluids from the working fluid source 2 and the working fluid source 102 is output to the 2 nd fluid pressure chamber 8b via the flow path 11e, the flow path 11d, and the 2 nd port P2. In the illustrated embodiment, the inlet throttle valve 105 is switched to the 1 st communication position 105X by the 1 st pilot pressure from the 1 st electromagnetic proportional valve 31, and is switched to the 2 nd communication position 105Z by the 2 nd pilot pressure from the 2 nd electromagnetic proportional valve 32. The 2 nd communication position 105Z is divided into a 2 nd single communication position 105Z1 that outputs the working fluid of only the working fluid source 2 of the working fluid source 2 and the working fluid source 102 arranged in parallel to the 2 nd fluid pressure chamber 8b, and a 2 nd multiple communication position 105Z2 that outputs the working fluid from both the working fluid source 2 and the working fluid source 102 to the 2 nd fluid pressure chamber 8 b. The inlet throttle 105 may be switched to the 2 nd single communication position 105Z1 when the 2 nd pilot pressure is lower than a predetermined reference pressure, and may be switched to the 2 nd multiple communication position 105Z2 when the 2 nd pilot pressure is equal to or higher than the predetermined reference pressure.

In the illustrated embodiment, the meter-in valve 105 may be configured to be able to output the working fluid from both the working fluid source 2 and the working fluid source 102 to the 1 st fluid pressure chamber 8 a. For example, the 1 st communication position 105X may be divided into a 1 st single communication position that outputs the working fluid of only the working fluid source 2 of the working fluid source 2 and the working fluid source 102 arranged in parallel to the 1 st fluid pressure chamber 8a, and a 1 st multiple communication position that outputs the working fluid from both the working fluid source 2 and the working fluid source 102 to the 1 st fluid pressure chamber 8 a. The inlet throttle 105 may be switched to the 1 st single communication position when the 1 st pilot pressure is lower than a predetermined reference pressure, and may be switched to the 1 st multiple communication position when the 1 st pilot pressure is equal to or higher than the predetermined reference pressure.

The actuator control device 101 operates substantially in the same manner as the actuator control device 1. When the inlet throttle 105 is switched to the 2 nd communication position 105Z2, the controller 10 excites the 2 nd electromagnetic proportional valve 32 so that the 2 nd pilot pressure becomes equal to or higher than a predetermined reference value.

Next, the operational effects of the above embodiment will be described. The actuator control devices 1 and 101 according to the above-described embodiments can switch the flow path between the actuator 8 and the

inlet throttle valve

5 and 105/outlet throttle valve 6 by causing the switching mechanism 20 to selectively output the 1 st pilot pressure output from the 1 st electromagnetic proportional valve 31 and the 2 nd pilot pressure output from the 2 nd electromagnetic proportional valve 32 to the

inlet throttle valve

5 and 105 and the outlet throttle valve 6. Thus, according to the actuator control device 1, the meter-in control and the meter-out control of the actuator 8 can be realized by controlling the two pilot pressures, i.e., the 1 st pilot pressure and the 2 nd pilot pressure. More specifically, in the above-described embodiment, the meter-in control and the meter-out control of the actuator 8 can be realized by two spools (the meter-in spool of the meter-in

valves

5, 105 and the meter-out spool of the meter-out valve 6) and two

electromagnetic pilot valves

31, 32. Therefore, according to the actuator control devices 1 and 101 of the above-described embodiments, the meter-in control and the meter-out control can be performed with a simple configuration as compared with the conventional IMV-type actuator control device that performs the meter-in control and the meter-out control using 4 spools (two meter-in spools and two meter-out spools) and 4 electromagnetic proportional valves.

According to the above-described embodiment, the switching mechanism 20 can be realized by the 1 st selector valve 21 and the 2 nd selector valve 22. Each of the 1 st selector valve 21 and the 2 nd selector valve 22 can be a two-position valve having a simple structure that can be switched between two positions. Therefore, according to the above-described embodiment, the switching mechanism 20 for the actuator control device can be realized with a simple configuration.

According to the above-described embodiment, when the 2 nd pilot pressure is not output from the 2 nd electromagnetic proportional valve 32 to the switching mechanism 20, the 1 st selector valve 21 is switched to the 1 st position 21X and the 2 nd selector valve 22 is switched to the 3 rd position 22X by controlling the 1 st electromagnetic proportional valve 31 to output the 1 st pilot pressure to the switching mechanism 20. This enables the switching mechanism 20 to be switched by controlling the 1 st electromagnetic proportional valve 31.

According to the above-described embodiment, when the 1 st pilot pressure is not output from the 1 st electromagnetic proportional valve 31 to the switching mechanism 20, the 2 nd pilot pressure is output to the switching mechanism 20 by controlling the 2 nd electromagnetic proportional valve 32, and the 1 st selector valve 21 is switched to the 2 nd position 21Y and the 2 nd selector valve 22 is switched to the 4 th position 22Y. This enables the switching mechanism 20 to be switched by controlling the 2 nd electromagnetic proportional valve 31.

According to the above-described embodiment, since the working fluid can be output to the actuator 8 at the flow rate corresponding to the 1 st pilot pressure or the 2 nd pilot pressure, the meter-in control can be performed by controlling both the 1 st electromagnetic proportional valve 31 and the 2 nd electromagnetic proportional valve 32.

According to the above-described embodiment, since the working fluid can be discharged from the actuator 8 at the flow rate corresponding to the 1 st pilot pressure or the 2 nd pilot pressure, the meter-out control can be performed by controlling both the 1 st electromagnetic proportional valve 31 and the 2 nd electromagnetic proportional valve 32.

According to the above-described embodiment, the working fluid from the two working

fluid sources

2 and 102 can be independently used to drive the actuator 8.

The dimensions, materials, and arrangements of the constituent elements described in the present specification are not limited to the dimensions, materials, and arrangements of the constituent elements described in the embodiments, and the constituent elements may be modified to have any dimensions, materials, and arrangements that are included in the scope of the present invention. Further, components not explicitly described in the present specification may be added to the embodiments described above, and a part of the components described in each embodiment may be omitted.

The throttle inlet 5, the throttle outlet 6, the 1 st selector valve 21, the 2 nd selector valve 22, the 1 st solenoid proportional valve 31, and the 2 nd solenoid proportional valve 32 may be provided in a single manifold (or valve main body), or may be provided in a plurality of manifolds in a distributed manner. When the valves are provided in a plurality of manifolds in a distributed manner, the actuator control devices 1 and 101 are fabricated by assembling the plurality of manifolds.

Claims

1. An actuator control device, wherein,

the actuator control device includes:

an outlet throttle valve that discharges the working fluid from a 1 st fluid pressure chamber of the actuator to the tank using a 1 st pilot pressure or a 2 nd pilot pressure;

an inlet throttle valve that outputs the working fluid from a working fluid source to a 2 nd fluid pressure chamber of the actuator using the 1 st pilot pressure or the 2 nd pilot pressure; and

a switching mechanism that switches based on at least one of the 1 st pilot pressure and the 2 nd pilot pressure to output one of the 1 st pilot pressure and the 2 nd pilot pressure to the outlet throttle and output the other of the 1 st pilot pressure and the 2 nd pilot pressure to the inlet throttle.

2. The actuator control device according to claim 1,

the switching mechanism switches by movement of the outlet throttle valve.

3. The actuator control device according to claim 1 or 2,

the switching mechanism includes: a 1 st selector valve that can be switched between a 1 st position at which the 1 st pilot pressure is output to the outlet throttle valve and a 2 nd position at which the 1 st pilot pressure is output to the inlet throttle valve; and a 2 nd selector valve that can be switched between a 3 rd position at which the 2 nd pilot pressure is output to the inlet throttle valve and a 4 th position at which the 2 nd pilot pressure is output to the outlet throttle valve.

4. The actuator control device according to claim 3,

the switching mechanism switches the 1 st selector valve to the 1 st position and the 2 nd selector valve to the 3 rd position in response to receiving the 1 st pilot pressure when the 2 nd pilot pressure is not supplied.

5. The actuator control device according to claim 3,

the switching mechanism switches the 1 st selector valve to the 2 nd position and the 2 nd selector valve to the 4 th position in response to receiving the 2 nd pilot pressure when the 1 st pilot pressure is not supplied.

6. The actuator control device according to any one of claims 1 to 5,

the inlet throttle outputs the working fluid to the actuator according to the 1 st pilot pressure or the 2 nd pilot pressure.

7. The actuator control device according to any one of claims 1 to 6,

the outlet throttle discharges the working fluid from the actuator according to the 1 st pilot pressure or the 2 nd pilot pressure.

8. The actuator control device according to any one of claims 1 to 7,

the inlet throttle valve is disposed between the actuator and a source of 1 st and 2 nd working fluid.

9. The actuator control device according to claim 8,

the throttle inlet valve is switched between: a position at which the working fluid is output to the actuator from either of the 1 st and 2 nd sources of working fluid; a position to output the working fluid to the actuator from both the 1 st and 2 nd sources of working fluid.

10. An actuator control device, wherein,

the actuator control device includes:

1 st electromagnetic proportional valve;

a 2 nd electromagnetic proportional valve;

an outlet throttle valve that is switched between a 1 st discharge position, at which working fluid is discharged from a 1 st fluid pressure chamber of the actuator to the tank, and a 1 st discharge position, at which working fluid is discharged from a 2 nd fluid pressure chamber of the actuator to the tank, by a 1 st pilot pressure output from the 1 st electromagnetic proportional valve, and is switched between a 2 nd discharge position, at which working fluid is discharged from a 2 nd fluid pressure chamber of the actuator to the tank, by a 2 nd pilot pressure output from the 2 nd electromagnetic proportional valve;

an inlet throttle valve that is switched by the 1 st pilot pressure to a 1 st communication position in which working fluid from a working fluid source is supplied to a 1 st fluid pressure chamber of the actuator, and is switched by the 2 nd pilot pressure to a 2 nd communication position in which working fluid from the working fluid source is supplied to a 2 nd fluid pressure chamber of the actuator; and

a switching mechanism, comprising: a 1 st selector valve that can be switched between a 1 st position at which the 1 st pilot pressure is supplied to the outlet throttle valve and a 2 nd position at which the 1 st pilot pressure is supplied to the inlet throttle valve; and a 2 nd selector valve which can be switched between a 3 rd position at which the 2 nd pilot pressure is supplied to the inlet throttle valve and a 4 th position at which the 2 nd pilot pressure is supplied to the outlet throttle valve, wherein the switching mechanism switches the 1 st selector valve from the 1 st position to the 2 nd position or switches the 2 nd selector valve from the 4 th position to the 3 rd position by movement of the outlet throttle valve.