KR20210028565A - Pressure regulating valve and construction machine - Google Patents

Abstract

According to the present invention, a pressure control valve comprises: a driving spool which can be moved in an axial direction; an electronic proportional valve having a control spool disposed in a different direction with respect to the axial direction and disposed on both sides of the driving spool in the axial direction; and a position compensation device compensating an actual position of the driving spool on a command position of the driving spool based on the electronic proportional valve based on displacement where the position of the driving spool in the axial direction is switched to the different direction with respect to the axial direction.

Description

PRESSURE REGULATING VALVE AND CONSTRUCTION MACHINE

The present invention relates to a pressure regulating valve and a construction machine.

Conventionally, a hydraulic excavator is known as a kind of construction machine. The hydraulic excavator includes attachments such as a boom, an arm, and a bucket that operate with a hydraulic cylinder. The hydraulic excavator is provided with a pressure adjustment valve that controls supply and discharge of hydraulic oil to a hydraulic cylinder. As the pressure regulating valve, there is one provided with a spool arranged in a spool hole extending into the inside of a valve block, and an actuator (force feedback type actuator) that always places the spool in the same position (see, for example, Patent Document 1). For example, the pressure regulating valve disclosed in Patent Document 1 has an hourglass-shaped piston installed at one end of the spool, an end block provided at one side of the valve block having a piston perforation matched with a spool perforation, and an end block in which the piston perforation extends. A first electrohydraulic valve disposed so as to be orthogonal to the direction, and a second electrohydraulic valve disposed next to the first electrohydraulic valve are provided.

Japanese Patent Publication No. 2003-269411

However, when the first electrohydraulic valve and the second electrohydraulic valve are concentrated only on one side of the valve block, there is a possibility that the configuration is complicated.

The present invention has been made to solve the above problems, and an object of the present invention is to provide a pressure regulating valve and a construction machine capable of simplifying the configuration.

As a means of solving the above problems, aspects of the present invention have the following configurations.

(1) A pressure regulating valve according to an aspect of the present invention has a drive spool movable in an axial direction and a control spool disposed to be movable in a direction different from the axial direction, and the drive spool is on both sides of the axial direction The actual driving with respect to the command position of the driving spool based on the electromagnetic proportional valve based on the disposed electromagnetic proportional valve and the displacement of the position of the driving spool in the axial direction converted to a direction different from the axial direction It has a position compensation mechanism for compensating the position of the spool.

According to this configuration, since the electromagnetic proportional valves are disposed on both sides of the drive spool in the axial direction, the structure can be simplified compared to the case where a plurality of valve mechanisms are concentrated only on one side of the drive spool in the axial direction.

(2) In the pressure regulating valve according to the above (1), the position compensation mechanism is disposed between the drive spool and the control spool, and is elastically deformed based on a position of the drive spool in the axial direction; And a piston disposed between the elastic member and a direction different from the axial direction of the drive spool.

(3) In the pressure regulating valve according to the above (2), the drive spool may have a surface whose diameter decreases toward one end in the axial direction and can directly or indirectly contact the piston.

(4) In the pressure regulating valve according to the above (3), the position compensation mechanism may include a sleeve having a step that regulates movement of the piston in a direction away from the surface of the drive spool.

(5) In the pressure regulating valve according to any one of (1) to (4) above, the electromagnetic proportional valve includes a control port that applies a pressure for moving the drive spool in the axial direction to the drive spool. And a drive device that applies the pressure to the drive spool through the control port by pulling the control spool.

(6) In the pressure regulating valve described in the above (5), the control spool may be at a position to connect the control port to the discharge path of the hydraulic oil when the electromagnetic proportional valve is not energized.

(7) In the pressure regulating valve according to (5) or (6) above, when only one of the electromagnetic proportional valves disposed on both sides of the drive spool in the axial direction is operated, the control port May be in a position that connects to the hydraulic oil discharge path.

(8) A pressure regulating valve according to an aspect of the present invention includes a drive spool having a surface that is movable in an axial direction and becomes smaller in diameter toward one end of the axial direction, and is movable in a direction different from the axial direction. It has a control spool disposed, and has a control port that applies pressure to the drive spool for moving the drive spool in the axial direction, and the pressure is applied to the drive spool through the control port by pulling the control spool. And a driving device to act on the basis of a displacement converted to a position of the driving spool in a direction different from the axial direction, and an electromagnetic proportional valve disposed on both sides of the driving spool in the axial direction, the position of the driving spool in the axial direction Compensates the actual position of the drive spool with respect to the command position of the drive spool based on the electromagnetic proportional valve, is disposed between the drive spool and the control spool, and is elastic based on the axial position of the drive spool An elastic member to be deformed, a piston disposed between the elastic member and a direction different from the axial direction of the driving spool and capable of directly or indirectly contacting the surface of the driving spool, and a direction away from the surface of the driving spool And a sleeve having a step that regulates the movement of the piston of the drive, and a position compensation mechanism disposed on both sides of the drive spool in the axial direction.

According to this configuration, since the electromagnetic proportional valve and the position compensation mechanism are disposed on both sides of the drive spool in the axial direction, the configuration can be simplified compared to the case where a plurality of valve mechanisms are concentrated only on one side in the axial direction of the drive spool. .

In addition, it is possible to compensate the position of the drive spool while operating the drive spool in both directions in the axial direction.

In addition, since the sleeve has a step, the movement of the piston in the direction away from the surface on the one end side in the axial direction of the drive spool can be controlled with a simple configuration.

(9) A construction machine according to an aspect of the present invention is provided with the pressure regulating valve according to any one of the above (1) to (8).

According to the present invention, it is possible to provide a pressure regulating valve and a construction machine that can simplify the configuration.

1 is a schematic diagram of a construction machine according to an embodiment.
2 is a cross-sectional view of a pressure regulating valve according to an embodiment.
3 is an enlarged view of a main part of FIG. 2.
4 is an explanatory diagram of an example of the operation of the pressure regulating valve when the drive spool of the embodiment is positioned in a neutral position.
5 is an explanatory diagram of an example of the operation of the pressure regulating valve when the first solenoid of the embodiment is operated.
6 is an explanatory diagram of an example of the operation of the pressure regulating valve when the second solenoid of the embodiment is operated.
7 is a cross-sectional view of a pressure regulating valve according to a modification of the embodiment.

Hereinafter, embodiments according to the present invention will be described with reference to the drawings. In the following embodiment, as a construction machine, a hydraulic excavator equipped with a pressure regulating valve is taken as an example and demonstrated. In addition, in the drawings used for the following description, the scale of each member is appropriately changed in order to make each member a recognizable size.

[Construction machinery]

1 is a schematic diagram of a construction machine 1 according to an embodiment.

For example, the construction machine 1 is a hydraulic excavator. The construction machine 1 includes a turning body 2 and a traveling body 3. The turning body 2 is provided on the traveling body 3 so that it can turn. The revolving body 2 is provided with a hydraulic pump 12 (fluid supply source) for supplying hydraulic oil (fluid).

The revolving body 2 includes a cab 5 in which an operator can ride, a boom 6 connected to the cab 5 so as to be swingable at one end, and the other end opposite to the cap 5 of the boom 6 ( The front end) includes an arm 7 connected to one end so as to be swingable, and a bucket 8 connected to the other end (tip) of the arm 7 opposite to the boom 6 so as to be swingable. The hydraulic pump 12 is arranged in the cap 5. The cap 5, the boom 6, the arm 7 and the bucket 8 are driven by hydraulic oil supplied from the hydraulic pump 12.

[Pressure adjustment valve]

2 is a cross-sectional view of the pressure regulating valve 10 of the embodiment. In FIG. 2, illustration of the axial center part of the valve body 20, the hydraulic pump 12 (refer FIG. 4), the hydraulic cylinder (hydraulic actuator), etc. is abbreviate|omitted. 3 is an enlarged view of a main part of FIG. 2. In FIG. 3, one side of the pressure regulating valve 10 is enlarged.

The pressure adjustment valve 10 controls supply and discharge of hydraulic oil to a hydraulic cylinder (not shown). As shown in Fig. 2, the pressure regulating valve 10 includes a valve body 20 having a plurality of passages 21 to 24, a drive spool 30 having an axis C1, and electromagnetic proportional valves 40A and 40B. ) And position compensation mechanisms 50A and 50B. The pressure regulating valve 10 is a spool type directional valve.

The plurality of passages 21 to 24 are passages (flow passages, pipes) through which hydraulic oil flows. The plurality of passages 21 to 24 include a spool hole 21, a first actuator passage 22, a second actuator passage 23 and a bypass passage 24.

The spool hole 21 is a hole into which the drive spool 30 can be inserted. The spool hole 21 penetrates the valve body 20 in the axial direction along the axis line C1.

The drive spool 30 is detachably inserted into the spool hole 21. The drive spool 30 includes a land (not shown) that can contact the inner circumferential surface of the spool hole 21. The drive spool 30 opens and closes the flow path and throttles it by moving in the axial direction. The flow rate of the hydraulic oil supplied to the hydraulic cylinder (not shown) is controlled according to the position of the drive spool 30.

The drive spool 30 has shaft portions 55 coupled to both ends in the axial direction (see Fig. 3). As shown in Fig. 3, the end portion of the shaft portion 55 has a surface 51 whose diameter decreases toward one end in the axial direction. The surface 51 has a conical shape whose tip becomes thinner as it moves away from the drive spool 30 in the axial direction of the drive spool 30. Specifically, the surface 51 has a conical shape whose tip is tapered as it is separated from the end surface of the shaft portion 55 on the opposite side to the drive spool 30 in the axial direction.

As shown in FIG. 2, the first actuator passage 22 is disposed on one side of the valve body 20. The first actuator passage 22 extends in a direction substantially orthogonal to the axis line C1. For example, one end of the first actuator passage 22 is connected to a rod side oil chamber (not shown) of the hydraulic cylinder. The other end of the first actuator passage 22 is connected to the spool hole 21.

The second actuator passage 23 is disposed on the other side of the valve body 20. That is, the second actuator passage 23 is disposed on the side opposite to the first actuator in the axial direction. The second actuator passage 23 extends in a direction substantially orthogonal to the axis line C1. For example, one end of the second actuator passage 23 is connected to a head side oil chamber (not shown) of the hydraulic cylinder. The other end of the second actuator passage 23 is connected to the spool hole 21.

The bypass passage 24 diverges from the spool hole 21. The bypass passage 24 is located on the side of the first actuator passage 22 and extends along the first actuator passage 22 and the first bypass passage 24a and the side of the second actuator passage 23 The second bypass path 24b is located at and extends along the second actuator passage 23, and the second bypass path 24b extends in a direction substantially parallel to the axial direction and ends at one end of the first bypass path 24a and the second bypass path. A third bypass path 24c connecting the other end of the furnace 24b is provided.

[Solenoid proportional valve]

As shown in Fig. 2, the electromagnetic proportional valves 40A and 40B are symmetrically disposed on both sides of the drive spool 30 in the axial direction. Hereinafter, the electromagnetic proportional valve 40A disposed on one side in the axial direction of the drive spool 30 is referred to as the ``first electromagnetic proportional valve 40A'', and the electromagnetic proportional valve disposed on the other side in the axial direction of the driving spool 30 The valve 40B is also referred to as "the second electromagnetic proportional valve 40B". When the drive spool 30 is in the neutral position in the axial direction, the first electromagnetic proportional valve 40A and the second electromagnetic proportional valve 40B are orthogonal to the axis line C1 and the center of the axial direction of the valve body 20 It has a line symmetry shape with the virtual line K1 passing through as the axis of symmetry.

Hereinafter, the configuration of the first electromagnetic proportional valve 40A as an electromagnetic proportional valve will be described. Since the second electromagnetic proportional valve 40B has the same configuration as the first electromagnetic proportional valve 40A, detailed descriptions are omitted.

As shown in Fig. 3, the first electromagnetic proportional valve 40A includes a control spool 41, a control port 42, and a solenoid 44 (drive unit).

The control spool 41 is provided separately from the drive spool 30. The control spool 41 is disposed so as to be movable in a direction different from the axial direction of the drive spool 30. In this embodiment, the control spool 41 is disposed so as to be movable in a direction orthogonal to the axial direction of the drive spool 30. The control spool 41 is disposed at a position forming an L-shape with the drive spool 30. The length of the control spool 41 in the axial direction is shorter than the length of the drive spool 30 in the axial direction (see Fig. 2).

Hereinafter, the axis line C2 orthogonal to the axis line C1 is referred to as "orthogonal axis line C2", and the direction along the orthogonal axis line C2 is also referred to as "orthogonal axis direction". The control spool 41 is disposed so as to be movable in the orthogonal axis direction. The ``orthogonal axis direction'' includes not only the case where the control spool 41 is actually orthogonal to the drive spool 30 (in contact with it), but also the case where the control spool 41 and the drive spool 30 are separated from each other. do. The control spool 41 has a first control passage 41a that is opened in the orthogonal axial direction to pass hydraulic oil, and a plurality of first control passages 41a that are opened in a radial direction orthogonal to the orthogonal axial direction to communicate with the first control passage 41a. It has 2 control passages 41b.

In the drawings, reference numeral 45 denotes a case provided on the side surface of the valve body 20 in the axial direction. The case 45 includes a pilot chamber 46 penetrating the case 45 in an orthogonal axial direction, a supply path 47 extending in a direction substantially perpendicular to the pilot chamber 46 (inward direction of the ground), The discharge path 48 is disposed at a position deviated by 90° from the supply path 47 with the orthogonal axis C2 as the central axis, and extends outward in the radial direction than the spool hole 21 and the discharge path 48 extending substantially parallel to the axis line C1. And a spring seal 49 extending substantially parallel to the axis line C1.

The pilot chamber 46 communicates with the spool hole 21. The pilot chamber 46 has a control port 42 that applies pressure for moving the drive spool 30 in the axial direction to the drive spool 30, and a receiving portion 43 for accommodating the sleeve 54. .

The control port 42 is located between the spool hole 21 and the receiving portion 43. The control port 42 is located on an extension of axis C1. The inner diameter (dimension in the radial direction) of the control port 42 is smaller than that of the spool hole 21.

The receiving portion 43 is in communication with the control port 42. The inner diameter (minimum dimension in the radial direction) of the receiving portion 43 is larger than that of the control port 42.

Reference numeral 35 in the drawing denotes a return spring disposed in the spring chamber 49. The return spring 35 is disposed coaxially with the drive spool 30. The return springs 35 are disposed on both sides of the drive spool 30 in the axial direction so as to hold the drive spool 30 at a neutral position in the axial direction (see Fig. 2).

The supply path 47 is a flow path for supplying hydraulic oil from the hydraulic pump 12 to the pilot chamber 46 (see Fig. 5).

The discharge path 48 supplies hydraulic oil to the tank 14 when the drive spool 30 is in a neutral position in the axial direction (see Fig. 4) or when only the second electromagnetic proportional valve 40B is operated (see Fig. 6). It is a flow path for discharge (storage) in ). The discharge path 48 is arranged to be offset from the supply path 47 in the orthogonal axial direction.

The solenoid 44 exerts a pressure on the drive spool 30 to move the drive spool 30 axially through the control port 42 by pulling the control spool 41. The solenoid 44 includes a pin 44a extending in the orthogonal axial direction. The solenoid 44 can move the pin 44a in the axial direction. The tip of the pin 44a is connected to the center of the cross section of the control spool 41 in the axial direction. Further, the solenoid 44 may be provided with a spring (stabilization spring) for correcting the position of the pin 44a in the axial direction.

[Location compensation mechanism]

The position compensation mechanisms 50A, 50B command the drive spool 30 based on the electromagnetic proportional valves 40A and 40B based on the displacement obtained by converting the position of the drive spool 30 in the axial direction into the orthogonal axial direction. It compensates for the position of the actual drive spool 30 relative to the position. As shown in Fig. 2, the position compensation mechanisms 50A and 50B are symmetrically disposed on both sides of the drive spool 30 in the axial direction. Hereinafter, the position compensation mechanism 50A disposed on one side in the axial direction of the drive spool 30 is referred to as “first position compensation mechanism 50A”, and the position compensation disposed on the other side in the axial direction of the drive spool 30 The mechanism 50B is also referred to as the "second position compensation mechanism 50B". When the drive spool 30 is in the neutral position in the axial direction, the first position compensation mechanism 50A and the second position compensation mechanism 50B have a line-symmetric shape with the imaginary line K1 as the axis of symmetry.

Hereinafter, the configuration of the first position compensation mechanism 50A as the position compensation mechanism will be described. Since the second position compensation mechanism 50B has the same configuration as the first position compensation mechanism 50A, detailed descriptions are omitted.

As shown in Fig. 3, the first position compensation mechanism 50A includes a spring 52 (elastic member), a piston 53, and a sleeve 54.

The spring 52 is disposed between the surface 51 (shaft portion 55) of the drive spool 30 and the control spool 41. The spring 52 is disposed coaxially with the control spool 41. The spring 52 is elastically deformed based on the position of the drive spool 30 in the axial direction. The spring 52 is a spring for feeding back the position of the drive spool 30 in the axial direction. The spring force of the spring 52 is much smaller than that of the return spring 35. The spring 52 is arranged between the control spool 41 and the piston 53.

The piston 53 is disposed between the spring 52 and the drive spool 30 in the orthogonal axial direction. The piston 53 is arranged coaxially with the control spool 41. The piston 53 may directly or indirectly contact the surface 51 of the drive spool 30. The piston 53 includes a body portion 53a having a first through hole 53h along an orthogonal axis C2 and a second through hole 53i opened in a direction orthogonal to the first through hole 53h, and the body A ball 53b rotatably provided so as to protrude from the central concave portion of the portion 53a toward the side of the surface 51 (shaft portion 55), and in the axis direction orthogonal from the outer periphery of the body portion 53a It includes an annular annular portion 53c of an annular shape extending to the side opposite to the surface 51.

One end of the spring 52 is in contact with the outer peripheral portion of the control spool 41. The other end of the spring 52 is in contact with the surface of the piston 53 on the side of the annular portion 53c of the body portion 53a.

A part of the ball 53b contacts the surface 51 or the shaft 55 of the drive spool 30.

The sleeve 54 is provided inside the case 45 (the receiving portion 43 of the pilot chamber 46). The sleeve 54 includes a cylindrical sleeve main body 54a accommodating the control spool 41, and a cylindrical outer cylindrical part 54b protruding from the outer circumference of the sleeve main body 54a toward the surface 51 (shaft part 55) side. ) And a step 54c that regulates movement in a direction away from the surface 51 (shaft portion 55) of the piston 53.

The sleeve body 54a is in contact with the outer peripheral surface of the control spool 41 from the outside in the radial direction so as to allow movement of the control spool 41 in the orthogonal axial direction. The length of the sleeve main body 54a in the orthogonal axial direction is longer than the control spool 41. The sleeve main body 54a has a plurality of communication holes 54h opened in a radial direction orthogonal to the orthogonal axial direction.

The outer circumferential cylinder portion 54b is from the control port (the end face of the sleeve body 54a in the orthogonal axial direction, the end face located in the receiving portion 43 of the pilot chamber 46 and the end face on the face 51 side). 42). The outer circumferential cylinder portion 54b is in contact with the outer circumferential surface of the piston 53 from the outside in the radial direction so as to allow movement of the piston 53 in the orthogonal axial direction. The length of the outer circumferential cylinder portion 54b in the orthogonal axial direction is longer than that of the piston 53.

The step 54c is a portion formed by the one end surface of the sleeve main body 54a and the inner circumferential surface of the outer cylindrical portion 54b in the orthogonal axial direction. The step 54c is a receiving portion in which the tip end of the annular portion 53c of the piston 53 can contact.

[Operation of pressure regulating valve]

4 is an explanatory view of an example of the operation of the pressure regulating valve 10 when the drive spool 30 of the embodiment is positioned in a neutral position.

As shown in Fig. 4, when the driving spool 30 is in the neutral position in the axial direction (hereinafter, also referred to as ``in the driving spool neutral position''), the pilot chamber 46 is connected to the discharge path 48. have. The drive spool neutral position corresponds to when the electromagnetic proportional valves 40A and 40B are not energized (hereinafter, also referred to as "when the electromagnetic proportional valve is not energized"). When the electromagnetic proportional valve is not energized, the pilot chamber 46 is connected to the discharge path 48.

In the drive spool neutral position, the first control passage 41a of the control spool 41 is discharged through the second control passage 41b of the control spool 41 and the communication hole 54h of the sleeve 54. ). In the drive spool neutral position, the flow path from the first control passage 41a of the control spool 41 to the supply passage 47 is closed by the sleeve body 54a.

In the drive spool neutral position, the hydraulic oil in the pilot chamber 46 is discharged to the tank 14 through the discharge path 48. Specifically, the hydraulic oil in the control port 42 includes the second through hole 53i and the first through hole 53h of the piston 53, the first control passage 41a and the second control passage of the control spool 41 ( 41b), the communication hole 54h of the sleeve 54, and the discharge passage 48 are flowed in this order and guided to the tank 14. Arrow W1 in the drawing indicates the flow of hydraulic oil in the neutral position of the drive spool.

5 is an explanatory diagram of an example of the operation of the pressure regulating valve 10 when the first solenoid (the solenoid 44 included in the first electromagnetic proportional valve 40A) of the embodiment operates.

As shown in Fig. 5, when the first solenoid pulls the control spool 41 in the direction away from the surface 51 of the drive spool 30 (in the direction of the arrow P1) (hereinafter also referred to as ``when the first solenoid is operated''). ), the supply passage 47 communicates with the first control passage 41a of the control spool 41 through the communication hole 54h of the sleeve 54 and the second control passage 41b of the control spool 41 do. During operation of the first solenoid, the flow path from the first control passage 41a of the control spool 41 to the discharge passage 48 is closed by the sleeve body 54a.

During operation of the first solenoid, hydraulic oil from the hydraulic pump 12 flows through the supply path 47 to the control port 42. Specifically, the hydraulic oil from the hydraulic pump 12 includes the supply path 47, the communication hole 54h of the sleeve 54, the second control passage 41b and the first control passage 41a of the control spool 41, The first through hole 53h and the second through hole 53i of the piston 53, and the control port 42 flow in this order. Arrow W2 in the drawing indicates the flow of hydraulic oil during operation of the first solenoid.

When the hydraulic oil flows through the control port 42, the pressure of the hydraulic oil acts on the surface 51 of the drive spool 30. Thereby, the pressure of the hydraulic oil acts on one end surface of the drive spool 30 in the axial direction through the face 51 and the shaft portion 55 of the drive spool 30. That is, the first solenoid pulls the control spool 41 in a direction away from the surface 51 of the drive spool 30 (in the direction of the arrow P1), and thus the drive spool 30 through the control port 42 is directed to the arrow V1. A pressure for moving in the direction (hereinafter, also referred to as "pilot pressure") is applied to one end surface of the drive spool 30 in the axial direction. Thereby, while the ball 53b of the piston 53 rotates along the inclination of the surface 51 of the drive spool 30, the spring 52 is extended in the orthogonal axial direction. The drive spool 30 stops where the spring force of the spring 52 and the pilot pressure are balanced. That is, the drive spool 30 stops at a place where the spring force of the spring 52 is balanced with the pilot pressure (hereinafter, also referred to as "balance position"). The drive spool 30 repeats the position control while slightly vibrating in the axial direction until it stops at the balance position.

6 is an explanatory diagram of an example of the operation of the pressure regulating valve 10 when the second solenoid (the solenoid 44 included in the second electromagnetic proportional valve 40B) of the embodiment operates.

As shown in FIG. 6, the driving spool 30 is moved in the direction of arrow V2 by the operation of the second solenoid (not shown) against the spring force of the return spring 35. When the second solenoid is actuated (hereinafter, also referred to as “when the second solenoid is actuated”), the return spring 35 contracts in the axial direction by receiving a load in the direction of arrow V2. Thereby, while the ball 53b of the piston 53 rotates along the outer peripheral surface of the shaft portion 55, the spring 52 contracts in the orthogonal axial direction. When the second solenoid is operated, the movement of the piston 53 in the direction away from the surface 51 (shaft part 55) of the driving spool 30 is regulated by the step 54c, so the spring 52 is orthogonal to the spring 52. The load in the axial direction is not applied excessively.

During operation of the second solenoid, the pilot chamber 46 is connected to the discharge path 48. During operation of the second solenoid, the first control passage 41a of the control spool 41 is discharged through the second control passage 41b of the control spool 41 and the communication hole 54h of the sleeve 54. ). When the second solenoid is operated, the flow path from the first control passage 41a of the control spool 41 to the supply passage 47 is closed by the sleeve body 54a.

When the second solenoid is operated, the hydraulic oil in the pilot chamber 46 is discharged to the tank 14 through the discharge path 48. Specifically, the hydraulic oil in the control port 42 includes the second through hole 53i and the first through hole 53h of the piston 53, the first control passage 41a and the second control passage of the control spool 41 ( 41b), the communication hole 54h of the sleeve 54, and the discharge passage 48 are flowed in this order and guided to the tank 14. Arrow W3 in the drawing indicates the flow of hydraulic oil during operation of the second solenoid.

As described above, the pressure regulating valve 10 according to the present embodiment has a drive spool 30 having a surface 51 that is movable in the axial direction and decreases in diameter toward one end in the axial direction, and is orthogonal. It has a control spool 41 arranged to be movable in the axial direction. The pressure regulating valve 10 according to the present embodiment has a control port 42 that applies pressure for moving the drive spool 30 in the axial direction to the drive spool 30. The pressure regulating valve 10 according to the present embodiment includes a solenoid 44 that applies pressure to the drive spool 30 via the control port 42 by pulling the control spool 41. In the pressure regulating valve 10 according to the present embodiment, the positions of the electromagnetic proportional valves 40A and 40B symmetrically disposed on both sides of the drive spool 30 in the axial direction and the drive spool 30 in the axial direction are orthogonal to each other. Position compensation mechanisms 50A, 50B for compensating the actual position of the driving spool 30 with respect to the command position of the driving spool 30 based on the electromagnetic proportional valves 40A, 40B based on the displacement converted in the axial direction. ). The pressure regulating valve 10 according to the present embodiment is disposed between the drive spool 30 and the control spool 41, and is elastically deformed based on the position of the drive spool 30 in the axial direction, A piston 53 disposed between the spring 52 and the drive spool 30 in the orthogonal axial direction and directly or indirectly contactable with the face 51 of the drive spool 30, and the face of the drive spool 30 ( A sleeve 54 having a step 54c that regulates the movement of the piston 53 in a direction away from 51 is provided. The position compensation mechanisms 50A and 50B included in the pressure regulating valve 10 according to the present embodiment are symmetrically disposed on both sides of the drive spool 30 in the axial direction.

According to this configuration, since the electromagnetic proportional valves 40A and 40B and the position compensation mechanisms 50A and 50B are disposed on both sides of the drive spool 30 in the axial direction, a plurality of valve mechanisms are arranged to the shaft of the drive spool 30. The configuration can be simplified compared to the case where it is concentrated only on one side of the direction.

In addition, the drive spool 30 can be operated in both directions in the axial direction and the position of the drive spool 30 can be compensated.

Furthermore, since the sleeve 54 has a step 54c, it is possible to realize the movement of the piston 53 in a direction away from the surface 51 of the drive spool 30 with a simple configuration.

In addition, since the electromagnetic proportional valves 40A and 40B and the position compensation mechanisms 50A and 50B are arranged symmetrically on both sides of the drive spool 30 in the axial direction, electrons are provided on both sides of the drive spool 30 in the axial direction. The proportional valves 40A and 40B and the position compensation mechanisms 50A and 50B can be shared in common, respectively. Therefore, compared to the case where the electromagnetic proportional valve and the position compensation mechanism are arranged asymmetrically on both sides of the drive spool 30 in the axial direction, the number of parts can be reduced, thereby reducing the cost.

In this embodiment, the control spool 41 is in a position to connect the control port 42 to the hydraulic oil discharge path 48 when the electromagnetic proportional valves 40A and 40B are not energized.

According to this configuration, when the electromagnetic proportional valve is not energized, pilot pressures are not generated for both ends of the drive spool 30 in the axial direction, so that the drive spool 30 can be smoothly moved in the axial direction.

In this embodiment, the control spool 41 is the control port 42 when only one of the electromagnetic proportional valves 40A and 40B disposed on both sides of the drive spool 30 in the axial direction (the second solenoid) is operated. Is in a position to connect to the hydraulic oil discharge path (48).

According to this configuration, when the second solenoid is operated, the pilot pressure on one end of the drive spool 30 in the axial direction is not generated, so that the drive spool 30 can be smoothly moved in the axial direction (arrow V2 direction). I can.

The construction machine 1 according to the present embodiment is provided with the pressure regulating valve 10.

According to this configuration, the construction machine 1 in which the configuration of the pressure regulating valve 10 is simplified can be provided.

In addition, the technical scope of the present invention is not limited to the above-described embodiment, and various changes can be made without departing from the spirit of the present invention.

For example, in the above-described embodiment, the construction machine 1 has been described as an example of a hydraulic excavator, but the present invention is not limited thereto. For example, you may apply this invention to construction machines other than hydraulic excavators, such as a hydraulic crane.

In the above-described embodiment, an example in which the sleeve 54 has a step 54c has been described, but the present invention is not limited thereto. For example, the sleeve 54 does not have to have a step 54c. For example, the sleeve 54 just needs to be in contact with the outer peripheral surface of the control spool 41 from the outside in the radial direction so as to allow movement of the control spool 41 in the orthogonal axial direction.

In the above-described embodiment, the example in which the electromagnetic proportional valves 40A and 40B and the position compensation mechanisms 50A and 50B are disposed symmetrically on both sides of the drive spool 30 in the axial direction has been described, but the present invention is not limited thereto. . For example, the electromagnetic proportional valves 40A and 40B and the position compensation mechanisms 50A and 50B may be disposed asymmetrically on both sides of the drive spool 30 in the axial direction.

In the above-described embodiment, an example in which the control spool 41 is disposed so as to be movable in a direction orthogonal to the axial direction of the drive spool 30 has been described. For example, the control spool 41 may be disposed so as to be movable in a direction obliquely crossing the axial direction of the drive spool 30. The ``intersecting direction'' includes not only the case where the control spool 41 actually crosses (contacts) the drive spool 30, but also the case where the control spool 41 and the drive spool 30 are separated do.

In the above-described embodiment, an example has been described in which the surface 51 of the drive spool 30 has a conical shape whose tip becomes tapered as it moves away from the drive spool 30 in the axial direction, but the present invention is not limited thereto. For example, as shown in FIG. 7, the surface 151 may have a curved shape in which the tip becomes thinner as it moves away from the drive spool 30 in the axial direction. In other words, the surface 151 may have a convex curved shape in a direction away from the drive spool 30 in the axial direction.

Further, for example, the drive spool 30 may have a recess recessed inward in the radial direction in the middle of the axial direction. In this case, the drive spool 30 may have a surface whose diameter decreases toward one end in the axial direction at an inner portion of the recess in the axial direction.

In the above-described embodiment, the piston 53 is rotatably provided so as to protrude toward the surface 51 (shaft portion 55) of the drive spool 30 in the orthogonal axial direction from the central concave portion of the body portion 53a. An example having a ball 53b has been described, but the present invention is not limited thereto. For example, the piston 53 need not have a ball 53b. For example, as shown in FIG. 7, the piston 153 may have a curved convex portion 153b having a curved shape convex toward the surface 151 (shaft portion 55) side in the orthogonal axial direction.

In addition, it is possible to replace the constituent elements in the above-described embodiments with known constituent elements without departing from the gist of the present invention. In addition, it is also possible to combine each of the above-described modified examples.

1: hydraulic excavator (construction machinery)
10: pressure regulating valve
20: valve body
21: spool hole (euro)
22: first actuator passage (passage)
23: second actuator passage (passage)
24: bypass passage (euro)
30: driven spool
35: return spring
40A: 1st electromagnetic proportional valve (electromagnetic proportional valve)
40B: second electromagnetic proportional valve (electromagnetic proportional valve)
41: control spool
42: control port
44: solenoid (drive unit)
50A: 1st position compensation mechanism (position compensation mechanism)
50B: second position compensation mechanism (position compensation mechanism)
51: cotton
52: spring (elastic member)
53: piston
54: sleeve
54c: step
151: cotton
153: piston
C1: axis

Claims (10)

A drive spool that can be moved in the axial direction,
An electromagnetic proportional valve having a control spool disposed to be movable in a direction different from the axial direction, and disposed on both sides of the drive spool in the axial direction,
A position for compensating the actual position of the driving spool with respect to the command position of the driving spool based on the electromagnetic proportional valve based on a displacement converted from the position of the driving spool in the axial direction in a direction different from the axial direction A pressure regulating valve provided with a compensating mechanism. The method of claim 1,
The position compensation mechanism,
An elastic member disposed between the driving spool and the control spool and elastically deformed based on a position of the driving spool in the axial direction;
And a piston disposed between the elastic member and a direction different from the axial direction of the drive spool. The method of claim 2,
The drive spool has a surface whose diameter decreases as it faces one end in the axial direction and can directly or indirectly contact the piston. The method of claim 3,
The pressure regulating valve, wherein the position compensation mechanism includes a sleeve having a step that regulates movement of the piston in a direction away from the surface of the drive spool. The method according to any one of claims 1 to 4,
The electromagnetic proportional valve,
It has a control port for acting on the drive spool a pressure for moving the drive spool in the axial direction,
And a drive device that applies the pressure to the drive spool through the control port by pulling the control spool. The method of claim 5,
The control spool is at a position to connect the control port to a discharge path of hydraulic oil when the electromagnetic proportional valve is not energized. The method of claim 5,
The control spool is at a position to connect the control port to a discharge path of hydraulic oil when only one of the electromagnetic proportional valves disposed on both sides of the drive spool in the axial direction is operated. The method of claim 6,
The control spool is at a position to connect the control port to a discharge path of hydraulic oil when only one of the electromagnetic proportional valves disposed on both sides of the drive spool in the axial direction is operated. A drive spool that is movable in an axial direction and has a surface whose diameter decreases as it faces one end in the axial direction,
It has a control spool disposed to be movable in a direction different from the axial direction, and has a control port that applies pressure to the drive spool to move the drive spool in the axial direction, and the control by pulling the control spool An electromagnetic proportional valve disposed on both sides of the drive spool in the axial direction, comprising a drive device for applying the pressure to the drive spool through a port,
Compensating the actual position of the driving spool with respect to the command position of the driving spool based on the electromagnetic proportional valve based on the displacement converted from the position of the driving spool in the axial direction in a direction different from the axial direction, An elastic member disposed between the driving spool and the control spool and elastically deformed based on a position of the driving spool in the axial direction, and disposed between the elastic member and a direction different from the axial direction of the driving spool, the A piston capable of directly or indirectly contacting the surface of the driving spool, and a sleeve having a step that regulates movement of the piston in a direction away from the surface of the driving spool, and both sides of the driving spool in the axial direction A pressure regulating valve having a position compensation mechanism disposed in the. A construction machine comprising the pressure regulating valve according to claim 1.

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