JP7449659B2 - Control valves, hydraulic circuits, hydraulic equipment and construction machinery - Google Patents

Description

The present invention relates to control valves, hydraulic circuits, hydraulic equipment, and construction machinery.

For example, as disclosed in Patent Document 1, a control valve having a valve body and a spool disposed in a spool hole of the valve body is known. The spool is provided with a notch, and the spool has a small diameter at the notch forming portion where the notch is provided. The two ports are connected via the spool hole because the cutout portion of the spool faces both of the two ports connected to the spool hole. On the other hand, since the land portion of the spool in which the notch is not formed is located between the two ports of the spool hole, the connection between the two ports is interrupted.

Japanese Patent Application Publication No. 8-170353

When connecting two ports with a conventional control valve, a cutout portion of the spool is located in the spool hole that connects the two ports. Therefore, when fluid flows between the two ports, a pressure loss occurs due to the presence of this notch formation. The present invention has been made in consideration of the above points, and an object of the present invention is to reduce pressure loss of a control valve.

The first control valve according to the invention comprises:
A valve body provided with a spool hole,
The valve body includes a first spool and a second spool that are movable within the spool hole of the valve body.

The second control valve according to the invention comprises:
a valve body provided with a spool hole and at least two ports communicating with the spool hole;
A first spool and a second spool are movable within the spool hole of the valve body and separated from each other when connecting the two ports at least through the spool hole.

The third control valve according to the invention is:
a valve body provided with a spool hole and at least two ports communicating with the spool hole;
A first spool and a second spool are movable within the spool hole of the valve body and connect the two ports through the spool hole while being spaced apart from each other.

The fourth control valve according to the invention is:
a valve body provided with a spool hole and at least a first port, a second port, and a common port communicating with the spool hole;
a first spool that is movable through the spool hole of the valve body and connectable to the first port and the common port via the spool hole;
a second spool that is movable in the spool hole of the valve body and that allows connection of the second port and the common port;
Equipped with

The fifth control valve according to the invention is:
A first spool hole and a first port communicating with the first spool hole, a second spool hole and a second port communicating with the second spool hole, and a common port communicating with the first spool hole and the second spool hole. the valve body,
a first spool that is movable in the first spool hole of the valve body and that is capable of connecting the first port and the common port via the first spool hole;
a second spool that is movable in the second spool hole of the valve body and that is capable of connecting the second port and the common port;
Equipped with

In the first to fifth control valves according to the present invention, the first spool and the second spool may move synchronously.

In the first to fifth control valves according to the present invention, the first spool and the second spool may move asynchronously.

In the first to fifth control valves according to the present invention, when the two ports are connected, the separation distance between the first spool and the second spool is longer than when the two ports are disconnected. It's okay.

The first to fifth control valves according to the present invention have a first back pressure chamber communicating with the spool hole through a through hole provided in the first spool, and a first back pressure chamber communicating with the spool hole through a through hole provided in the second spool. A second back pressure chamber communicating with the spool hole may be provided.

The first to third control valves according to the present invention may include a first movement control section that controls movement of the first spool, and a second movement control section that controls movement of the second spool. good.

The first to third control valves according to the present invention include a first movement control section that controls the supply of pilot pressure oil for driving the first spool, and a supply of pilot pressure oil for driving the second spool. A second movement control section may be provided.

In the first to third control valves according to the present invention, when the first spool moves to one side, the second spool also moves to one side, and when the first spool moves to the other side, The second spool may be stationary.

The first to third control valves according to the present invention may include a movement control that controls the supply of pilot pressure oil for driving the first spool and the second spool.

The hydraulic circuit according to the present invention includes any one of the first to third control valves according to the present invention described above.

The hydraulic equipment according to the present invention includes:
Any of the hydraulic circuits according to the present invention described above,
an actuator controlled by the hydraulic circuit.

A construction machine according to the present invention includes any of the hydraulic circuits according to the present invention described above.

According to the present invention, pressure loss of the control valve can be effectively reduced.

FIG. 1 is a diagram for explaining one embodiment, and is a diagram showing a specific example of a control valve incorporated in a construction machine, hydraulic equipment, and a hydraulic circuit. FIG. 2 is a sectional view schematically showing the configuration of the control valve in FIG. 1, and is a diagram for explaining the operation of the control valve. FIG. 3 is a sectional view corresponding to FIG. 2, and is a diagram for explaining the operation of the control valve. FIG. 4 is a sectional view corresponding to FIG. 2, and is a diagram for explaining the operation of the control valve. FIG. 5 is a sectional view corresponding to FIG. 1, and is a diagram for explaining a modified example of the control valve. FIG. 6 is a sectional view schematically showing the configuration of the control valve in FIG. 5, and is a diagram for explaining the operation of the control valve in FIG. FIG. 7 is a sectional view corresponding to FIG. 2, and is a diagram for explaining another modification of the control valve. FIG. 8 is a sectional view corresponding to FIG. 2, and is a diagram for explaining still another modification of the control valve.

Hereinafter, one embodiment of the present invention will be described with reference to specific examples shown in the drawings. It should be noted that the elements shown in each drawing may include elements whose size, scale, etc. are shown different from the actual ones in order to facilitate understanding.

The control valve 30 described below is a device that switches between supplying and stopping supply of liquid to which pressure is applied, particularly pressure oil. The control valve 30 is used by being incorporated into a hydraulic circuit including a liquid supply passage, for example, as in the example described below, the hydraulic circuit 20 including a pressure oil supply passage. The hydraulic circuit and the hydraulic circuit 20 are applied to a machine for performing construction work, that is, the construction machine 10, as an example. Examples of the construction machine 10 include a shovel car, a crane truck, a forklift, and the like. A hydraulic circuit 20 applied to the construction machine 10 includes an actuator 18 connected to mechanical equipment 13 such as a shovel, a crane, a forklift, a hammer, and a traveling means, and a hydraulic device 15. The hydraulic circuit 20 controls the operation of the actuator 18 by supplying pressure oil to the actuator 18 and discharging the pressure oil from the actuator 18 . The actuator 18 operates to drive the mechanical equipment 13.

The control valve 30 will be explained in more detail below. As shown in FIG. 1, the control valve 30 includes a valve body 40, and a first spool 60 and a second spool 70 that are movable within the spool hole 41 of the valve body 40. A spool hole 41 is provided in the valve body 40 . The spool hole 41 is an elongated hole, and forms, for example, a cylindrical space. The first spool 60 and the second spool 70 are movable within the spool hole 41 along the central axis CA of the spool hole 41.

Furthermore, in the control valve 30 in this embodiment, the valve body 40 is provided with a first port 47B, a second port 48B, and a common port 46B that communicate with the spool hole 41. By moving the first spool 60 within the spool hole 41, connection and disconnection between the first port 47B and the common port 46B via the spool hole 41 can be switched. Furthermore, by moving the second spool 70 within the spool hole 41, connection and disconnection between the second port 48B and the common port 46B via the spool hole 41 can be switched.

Hereinafter, the direction parallel to the central axis CA of the spool hole 41, that is, the direction of movement of the first spool 60 and the second spool 70, will be referred to as the axial direction AD. Further, one side in the axial direction AD (the right side in the plane of FIG. 1) is defined as one side SA, and the other side (the left side in the plane of FIG. 1) is defined as the other side SB. In order to clarify the directional relationship between the drawings, in FIGS. 1 to 7, the axial direction AD, one side SA, and the other side SB are shown as being common among the drawings. Moreover, the "outside" in the axial direction AD refers to the side away from the center of the control valve 30 in the axial direction AD. Conversely, "inside" in the axial direction AD refers to the side closer to the center of the control valve 30 in the axial direction AD.

A supply passage P and a tank passage T are formed in the valve body 40. The supply passage P communicates with a hydraulic pressure sending means such as a pump of the hydraulic circuit 20. The supply passage P is normally filled with or flows with pressure oil maintained at a high pressure. On the other hand, the tank passage T is a passage that collects pressure oil that is not supplied to the actuator 18 and pressure oil that is discharged from the actuator 18. Tank passage T typically leads to a tank (not shown). The pressure oil recovered into the tank via the tank passage T is sent to the supply passage P again by the pressure oil sending means.

The valve body 40 is provided with a first supply port 47A and a second supply port (first port described above) 47B that communicate with the supply passage P via the check valve CV. The first supply port 47A and the second supply port 47B open to the spool hole 41 and communicate with the spool hole 41. Further, the valve body 40 is provided with a first discharge port 48A and a second discharge port (the above-mentioned second port) 48B that communicate with the tank passage T. The first discharge port 48A and the second discharge port 48B open to the spool hole 41 and communicate with the spool hole 41.

Further, the valve body 40 is provided with a first actuator port 46A and a second actuator port (common port) 46B that communicate with the actuator 18. The first actuator port 46A and the second actuator port 46B communicate with different chambers of the hydraulic cylinder forming the actuator 18. In the illustrated example, the second actuator port 46B communicates with the rod chamber 18a through which the rod passes. The first actuator port 46A communicates with the piston chamber 18b on the side through which the rod does not penetrate. The first actuator port 46A and the second actuator port 46B open to and communicate with the spool hole 41.

In the illustrated example, the first discharge port 48A, the first actuator port 46A, and the first supply port 47A communicate with the spool hole 41 in a region on one side SA in the axial direction AD. The connection positions (opening positions) of the first discharge port 48A, the first actuator port 46A, and the first supply port 47A to the spool hole 41 are in this order from one side SA in the axial direction AD. Similarly, in the illustrated example, the second discharge port 48B, the second actuator port 46B, and the second supply port 47B communicate with the spool hole 41 in a region on the other side SB in the axial direction AD. The connection positions (opening positions) of the second discharge port 48B, the second actuator port 46B, and the second supply port 47B to the spool hole 41 are in this order from the other side SB in the axial direction AD.

In the example shown in FIG. 1, the valve body 40 includes a valve block 50, a first side block 51X fixed to the valve block 50 from one side SA in the axial direction AD, and the other side SB in the axial direction AD. and a second side block 51Y fixed to the valve block 50. In the illustrated example, the above-mentioned passages P, T and ports 46A, 46B, 47A, 47B, 48A, 48B are formed in the valve block 50. On the other hand, the spool hole 41 passes through the valve block 50 and extends from the valve block 50 into the first side block 51X and the second side block 51Y.

Next, the first spool 60 and the second spool 70 will be explained. The first spool 60 and the second spool 70 are separately provided members. The first spool 60 and the second spool 70 are rod-shaped members. The first spool 60 and the second spool 70 have a cross section corresponding to the cross-sectional shape of the spool hole 41. By positioning the first spool 60 or the second spool 70 within the spool hole 41, pressure oil is restricted from flowing in the axial direction AD within the corresponding portion of the spool hole 41.

The first spool 60 has a first end surface 62 facing inward in the axial direction AD, and a first base end surface 63 facing outside (one side SA) in the axial direction AD. The first spool 60 is provided with a first through hole 61 that penetrates between the first distal end surface 62 and the first proximal end surface 63. The first spool 60 has a first bulging portion 64 that is widened (increased in diameter) in a region that is one side SA in the axial direction AD. The first spool 60 bulges in a direction perpendicular to the axial direction AD at the first bulge portion 64 . The first bulging portion 64 forms a first one-side shoulder portion 64X that faces one side SA in the axial direction AD, and a first other-side shoulder portion 64Y that faces the other side SB in the axial direction AD. Further, the first spool 60 has a notch forming portion 65 having a narrow width (reduced diameter) in a region between the first distal end surface 62 and the first bulging portion 64 in the axial direction AD. That is, the first spool 60 forms a notch 65C in the notch forming portion 65, and as a result is recessed in a direction perpendicular to the axial direction AD.

Similarly, the second spool 70 has a second distal end surface 72 facing inward in the axial direction AD, and a second proximal end surface 73 facing outward (other side SA) in the axial direction AD. The second spool 70 is provided with a second through hole 71 that penetrates between the second distal end surface 72 and the second proximal end surface 73. In the illustrated example, the first spool 60 is located on one side SA of the second spool 70 in the axial direction AD. The second tip surface 72 of the second spool 70 faces the first tip surface 62 of the first spool 60 in the axial direction AD. Further, the second spool 70 has a second bulging portion 74 that is widened (increased in diameter) in a region that is the other side SB in the axial direction AD. That is, the second spool 70 bulges in the direction perpendicular to the axial direction AD at the second bulge portion 74 . The second bulging portion 74 forms a second one-side shoulder portion 74X facing one side SA in the axial direction AD, and a second other-side shoulder portion 74Y facing the other side SB in the axial direction AD.

The first spool 60 and the second spool 70 connect two ports via the spool hole 41 or connect two ports via the spool hole 41 by moving in the axial direction AD within the spool hole 41. Break the connection. In the illustrated example, the two ports that are connected and disconnected are two ports that communicate with the spool hole 41 at adjacent positions in the axial direction AD.

In the illustrated example, the first spool 60 switches between connecting and disconnecting the first actuator port 46A and the first supply port 47A, and also disconnects and disconnects the first actuator port 46A and the first discharge port 48A. Switch. As described above, the first spool 60 has a cross section corresponding to the cross-sectional shape of the spool hole 41. Therefore, by positioning the first spool 60 within the spool hole 41, flow of pressure oil in the axial direction AD within the spool hole 41 is restricted. On the other hand, the first spool 60 has a notch 65C formed in the notch forming portion 65. Then, the connecting positions (opening positions) of the two ports to the spool hole 41 overlap in the axial direction AD, in other words, both the connecting positions (opening positions) of the two ports to the spool hole 41 overlap in the axial direction AD. By arranging the notch forming portion 65 so as to face each other in a direction perpendicular to the notch, two ports adjacent in the axial direction AD are connected to each other via the notch 65C. That is, by moving the first spool 60 provided with the notch 65C in the axial direction AD, connection and disconnection between the first actuator port 46A and the first supply port 47A can be switched, and the first actuator port 46A and the first supply port 47A can be connected and disconnected. 46A and the first discharge port 48A are switched between disconnection and connection.

In this embodiment, the first end surface 62 of the first spool 60 and the second spool 70 can be separated from each other in the axial direction AD. At this time, a space S is formed between the first tip surface 62 of the first spool 60 and the second tip surface 72 of the second spool 70. This space S functions similarly to the notch 65C of the first spool 60 to switch between connecting and disconnecting the two ports. Specifically, the connecting positions (opening positions) of the two ports to the spool hole 41 are overlapped in the axial direction AD, in other words, the connecting positions (opening positions) of the two ports to the spool hole 41 are both overlapped in the axial direction AD. By forming the space S so as to face each other in a direction perpendicular to the axial direction AD, two ports adjacent in the axial direction AD are connected to each other via the space S. In the illustrated example, the first spool 60 and the second spool 70 connect the second actuator port (common port) 46B and the second supply port (first port) 47B by adjusting the position of the space S. In addition, it is possible to switch between blocking and connecting the second actuator port (common port) 46B and the second discharge port (second port) 48B.

Next, a configuration for moving the first spool 60 and the second spool 70 in the axial direction AD will be described. First, a first side chamber 43AX and a first other side chamber 43AY are provided between the first spool 60 and the valve body 40. The first side chamber 43AX is formed on one side SA of the first bulging portion 64 of the first spool 60 in the axial direction AD. The first shoulder portion 64X of the first bulging portion 64 constitutes a part of the wall portion that partitions the first side chamber 43AX. The first one-side shoulder portion 64X facing one side SA in the axial direction AD is pushed toward the other side SB in the axial direction AD by the pressure within the first one-side chamber 43AX. The valve body 40 is provided with a first side passage 44AX that communicates with the first side chamber 43AX. Similarly, the first other side chamber 43AY is formed on the other side SB of the first bulging portion 64 of the first spool 60 in the axial direction AD. The first other side shoulder portion 64Y of the first bulging portion 64 constitutes a part of the wall portion that partitions the first other side chamber 43AY. The first other side shoulder portion 64Y facing the other side SB in the axial direction AD is pushed toward the one side SA in the axial direction AD by the pressure within the first other side chamber 43AY. The valve body 40 is provided with a first other side passage 44AY communicating with the first other side chamber 43AY.

In the illustrated example, the first side chamber 43AX and the first other side chamber 43AY are formed between the first spool 60 and the first side block 51X. Further, the first first side passage 44AX and the first other side passage 44AY are formed in the first side block 51X.

Furthermore, the control valve 30 further includes a movement control section 80 that controls movement of the first spool 60 in the axial direction AD. In the illustrated example, the movement control unit 80 switches between supplying and stopping the supply of pilot pressure oil to the first one-side passage 44AX and the first other-side passage 44AY. Such movement control section 80 can typically be a switching valve.

Note that the first spool 60 has the first through hole 61 formed therein as described above. The valve body 40 is provided with a first back pressure chamber 42A that communicates with the spool hole 41 in which the first end surface 62 is located via the first through hole 61 of the first spool 60. The first base end surface 63 of the first spool 60 constitutes a part of the wall portion that partitions the first back pressure chamber 42A. The first base end surface 63 facing one side SA in the axial direction AD is pushed toward the other side SB in the axial direction AD by the pressure within the first back pressure chamber 42A. On the other hand, the first end surface 62 facing the other side SB in the axial direction AD is pushed toward the one side SA in the axial direction AD by the pressure within the spool hole 41 (space S). The pressure in the first back pressure chamber 42A is maintained the same as the pressure in the spool hole 41 (space S) by the pressure oil flowing through the first through hole 61. By making the area of the first distal end surface 62 and the area of the first proximal end surface 63 the same, the force applied to the first distal end surface 62 and the force applied to the first proximal end surface 63 are made the same. can do. Therefore, even if high-pressure oil is flowing into the space S, for example, it is possible to move the first spool 60 smoothly with a small force.

Further, the valve body 40 has a first positioning means 56A for positioning the first spool 60 in a state where no driving force for movement is applied, that is, in a neutral state. In the illustrated example, the first positioning means 56A includes a first one side pushing member 57AX arranged in the first one side chamber 43AX and a first other side pushing member 57AY arranged in the first other side chamber 43AY. ,have. The first first side pushing member 57AX is arranged between the valve body 40 and the first one side shoulder portion 64X of the first spool 60. The first one-side pushing member 57AX pushes the first spool 60 to the other side SB in the axial direction AD via the first one-side shoulder portion 64X. The first other side pushing member 57AY is arranged between the valve body 40 and the first other side shoulder portion 64Y of the first spool 60. The first other side pushing member 57AY pushes the first spool 60 to the one side SA in the axial direction AD via the first other side shoulder portion 64Y. A driving force is applied to a position in the axial direction AD where the force of the first side pushing member 57AX pushing the first spool 60 and the force pushing the first other side pushing member 57AY pushing the first spool 60 are balanced. It is possible to position the first spool 60 that is not in use. The first one side pushing member 57AX and the first other side pushing member 57AY are elastic bodies, typically compression springs, which are housed in the first first side chamber 43AX or the first other side chamber 43AY in a compressed state. Can be done.

On the other hand, a second one side chamber 43BX and a second other side chamber 43BY are provided between the second spool 70 and the valve body 40. The second one-side chamber 43BX is formed on one side SA of the second bulging portion 74 of the second spool 70 in the axial direction AD. The second one-side shoulder portion 74X of the second bulging portion 74 constitutes a part of the wall portion that partitions the second one-side chamber 43BX. The second one-side shoulder portion 74X facing one side SA in the axial direction AD is pushed toward the other side SB in the axial direction AD by the pressure within the second one-side chamber 43BX. The valve body 40 is provided with a second first side passage 44BX communicating with the second first side chamber 43BX. Similarly, the second other side chamber 43BY is formed on the other side SB of the second bulging portion 74 of the second spool 70 in the axial direction AD. The second other side shoulder portion 74Y of the second bulging portion 74 constitutes a part of the wall portion that partitions the second other side chamber 43BY. The second other side shoulder portion 74Y facing the other side SB in the axial direction AD is pushed toward the one side SA in the axial direction AD by the pressure within the second other side chamber 43BY. The valve body 40 is provided with a second other side passage 44BY communicating with the second other side chamber 43BY.

In the illustrated example, the second one side chamber 43BX and the second other side chamber 43BY are formed between the second spool 70 and the second side block 51Y. Further, the second first side passage 44BX and the second other side passage 44BY are formed in the second side block 51Y.

The movement control unit 80 described above also controls movement of the second spool 70 in the axial direction AD. The movement control unit 80 switches between supplying and stopping the supply of pilot pressure oil to the second first side chamber 43BX. The second one-side passage 44BX leading to the second one-side chamber 43BX communicates with the first one-side passage 44AX leading to the first one-side chamber 43AX. Under the control of the movement control unit 80, when the pilot pressure oil is supplied to the first first side chamber 43AX, the pilot pressure oil is also supplied to the second first side chamber 43BX. Further, when the supply of pilot pressure oil to the first side chamber 43AX is stopped under the control of the movement control unit 80, the supply of pilot pressure oil to the second side chamber 43BX is also stopped.

Similar to the first spool 60, the second spool 70 has a second through hole 71 formed therein. The valve body 40 is provided with a second back pressure chamber 42B that communicates with the spool hole 41 in which the second tip end surface 72 is located via the second through hole 71 of the second spool 70. The second base end surface 73 of the second spool 70 constitutes a part of the wall portion that partitions the second back pressure chamber 42B. The second base end surface 73 facing the other side SB in the axial direction AD is pushed toward the one side SA in the axial direction AD by the pressure within the second back pressure chamber 42B. Similarly to the first spool 60, by making the area of the second distal end surface 72 and the area of the second proximal end surface 73 the same, the force applied to the second distal end surface 72 and the force applied to the second proximal end surface 73 are power can be made the same. Therefore, even if high-pressure oil is flowing into the space S, for example, it is possible to move the second spool 70 smoothly with a small force.

Further, the valve body 40 has a second positioning means 56B for positioning the second spool 70 in a state where no driving force for movement is applied, that is, in a neutral state. In the illustrated example, the second positioning means 56B includes a second other side pushing member 57BY disposed within the second other side chamber 43BY. The second other side pushing member 57BY is arranged between the valve body 40 and the second other side shoulder portion 74Y of the second spool 70. The second other side pushing member 57BY pushes the second spool 70 to the one side SA in the axial direction AD via the second other side shoulder portion 74Y. In the illustrated example, the second one-side pushing member is not provided in the second one-side chamber 43BX. When the second other side pushing member 57BY pushes the second spool 70, the first spool 60, which is not loaded with driving force, can be positioned on the one side SA in the axial direction AD. That is, in the illustrated example, the second spool 70 can be moved to the one side SA in the axial direction AD by the second positioning means 56B even if the pilot pressure oil is not supplied to the second other side passage 44BY. . The second other side pushing member 57BY can be an elastic body, typically a compression spring, housed in the second other side chamber 43BY in a compressed state.

Next, the operation of the control valve 30 having the above configuration will be explained mainly with reference to FIGS. 2 to 4. 2 to 4 are cross-sectional views schematically showing the components of the control valve 30 shown in FIG. 1. FIG.

In the state shown in FIG. 2, the movement control unit 80 does not supply pilot pressure oil to any of the passages 44AX, 44AY, 44BX, and 44BY. That is, the movement control unit 80 has stopped supplying pilot pressure oil to each chamber 43AX, 43AY, 43BX, and 43BY. The control valve 30 shown in FIG. 2 is in a so-called neutral position. At this time, the first spool 60 is placed at a predetermined position determined by the first positioning means 56A. Similarly, the second spool 70 is placed at a predetermined position determined by the second positioning means 56B.

In the state of FIG. 2, the notch forming portion 65 in which the notch 65C of the first spool 60 is formed overlaps only the first actuator port 46A in the axial direction AD, and is shifted from the other ports in the axial direction AD. In other words, the notch forming portion 65 faces only the first actuator port 46A in the direction perpendicular to the axial direction AD, and does not face the other ports. Therefore, the first actuator port 46A does not communicate with either the first supply port 47A or the first discharge port 48A.

Similarly, in the state of FIG. 2, the space S between the first spool 60 and the second spool 70 overlaps only with the second actuator port (common port) 46B in the axial direction AD, and is separated from the other ports in the axial direction. It is shifted to AD. In other words, the space S faces only the second actuator port 46B in a direction perpendicular to the axial direction AD, and does not face other ports. Therefore, the second actuator port (common port) 46B does not communicate with either the second supply port (first port) 47B or the second discharge port (second port) 48B. According to another expression, the first spool 60 is located in a portion of the spool hole 41 between the second actuator port (common port) 46B and the second supply port (first port) 47B, and The two actuator ports (common port) 46B and the second supply port (first port) 47B are shut off. The second spool 70 is located in a portion of the spool hole 41 between the second actuator port (common port) 46B and the second discharge port (second port) 48B, and the second actuator port (common port) 46B and a second discharge port (second port) 48B are shut off.

Next, in the state shown in FIG. 3, the movement control unit 80 supplies pilot pressure oil to the first one-side passage 44AX and the second one-side passage 44BX. That is, pilot pressure oil is supplied to the first side chamber 43AX and the second side chamber 43BX. As a result, the pilot pressure oil is discharged from the first other side chamber 43AY and the second other side chamber 43BY, and the first spool 60 and the second spool 70 are moved from the neutral position shown in FIG. 2 to the position shown in FIG. , it moves to the other side SB in the axial direction AD.

In the state of FIG. 3, the notch forming part 65 formed with the notch 65C of the first spool 60 overlaps both the first actuator port 46A and the first supply port 47A in the axial direction AD, and is separated from the other ports in the axial direction. It is shifted to AD. In other words, the notch forming portion 65 faces both the first actuator port 46A and the first supply port 47A in the direction perpendicular to the axial direction AD, and does not face the other ports. As a result, the first actuator port 46A communicates with the first supply port 47A via the portion of the spool hole 41 where the notch 65C is located. Then, the pressure oil supplied from the supply passage P passes through the first supply port 47A and the first actuator port 46A, and flows into the piston chamber 18b of the actuator 18.

In addition, in the state of FIG. 3, the space S between the first spool 60 and the second spool 70 overlaps both the second actuator port 46B and the second discharge port 48B in the axial direction AD, and is axially separated from the other ports. It is shifted in direction AD. In other words, the space S faces both the second actuator port 46B and the second discharge port 48B in the direction perpendicular to the axial direction AD, and does not face the other ports. As a result, the second actuator port 46B communicates with the second discharge port 48B via the portion of the spool hole 41 where the space S is located. Pressure oil discharged from the rod chamber 18a of the actuator 18 passes through the second actuator port 46B and the second discharge port 48B, and is collected in a tank (not shown).

According to another expression, in the state shown in FIG. The second actuator port (common port) 46B and the second supply port (first port) 47B are isolated from each other. On the other hand, the second spool 70 has a second discharge port (second port) 48B larger than a portion of the spool hole 41 between the second actuator port (common port) 46B and the second discharge port (second port) 48B. A second discharge port (second port) 48B is at least partially opened in the spool hole 41. Thereby, the second spool 70 connects the second actuator port (common port) 46B and the second discharge port (second port) 48B.

In this embodiment, the first spool 60 and the second spool 70 are separate members. Therefore, the connecting portion 90 having a narrow width (small diameter) as shown by the two-dot chain line in FIG. 3 does not exist between the first spool 60 and the second spool 70. Therefore, the flow path in the spool hole 41 for the pressure oil flowing from the second actuator port 46B to the second discharge port 48B can be made thicker. In other words, it is possible to increase the cross-sectional area of the pressure oil flow path from the second actuator port 46B to the second discharge port 48B. In addition, the frictional resistance of the pressure oil flowing from the second actuator port 46B to the second discharge port 48B can be reduced. Thereby, pressure loss within the control valve 30 can be significantly reduced compared to the case where the connecting portion 90 is provided.

Next, in the state shown in FIG. 4, the movement control unit 80 supplies pilot pressure oil to the first other side chamber 43AY. That is, pilot pressure oil is supplied to the first other side chamber 43AY. As a result, the pilot pressure oil is discharged from the first side chamber 43AX, and the first spool 60 is moved from the neutral position shown in FIG. 2 to the one side SA in the axial direction AD, as shown in FIG. Moving.

In the state of FIG. 4, the notch forming part 65 formed with the notch 65C of the first spool 60 overlaps both the first actuator port 46A and the first discharge port 48A in the axial direction AD, and is separated from the other ports in the axial direction. It is shifted to AD. In other words, the notch forming portion 65 faces both the first actuator port 46A and the first discharge port 48A in the direction perpendicular to the axial direction AD, and does not face the other ports. As a result, the first actuator port 46A communicates with the first discharge port 48A through the portion of the spool hole 41 where the notch 65C is located. Pressure oil discharged from the piston chamber 18b of the actuator 18 passes through the first actuator port 46A and the first discharge port 48A, and is collected in a tank (not shown).

In the state of FIG. 4, the space S between the first spool 60 and the second spool 70 overlaps both the second actuator port 46B and the second supply port 47B in the axial direction AD, and is separated from the other ports in the axial direction. It is shifted to AD. In other words, the space S faces both the second actuator port 46B and the second supply port 47B in the direction perpendicular to the axial direction AD, and does not face the other ports. As a result, the second actuator port 46B communicates with the second supply port 47B via the portion of the spool hole 41 where the space S is located. Then, the pressure oil supplied from the supply passage P passes through the second supply port 47B and the second actuator port 46B, and flows into the rod chamber 18a of the actuator 18.

According to another expression, in the state shown in FIG. is also located on the second supply port (first port) 47 side, and the second supply port (first port) 47B is at least partially opened in the spool hole 41. Thereby, the first spool 60 connects the second actuator port (common port) 46B and the second supply port (first port) 47B.

In the illustrated example, the movement control unit 80 does not supply pilot pressure oil to the first side chamber 43AX and the second other side chamber 43BY in the state shown in FIG. At this time, the second spool 70 is positioned by the second other side pushing member 57BY of the second positioning means 56B. That is, in the state shown in FIG. 4, the first spool 60 has moved from the state shown in FIG. 2 to one side SA along the axial direction AD, but the second spool 70 has moved from the state shown in FIG. It is located at the same position in the axial direction AD as in the illustrated state. That is, the first spool 60 and the second spool 70 are moving asynchronously.

Then, the separation distance along the axial direction AD of the first spool 60 and the second spool 70 in the state of FIG. 4 in which the two ports (specifically, the second actuator port 46B and the second supply port 47B) are connected. LD is longer than the separation distance LD along the axial direction AD between the first spool 60 and the second spool 70 in the state of FIG. 2 in which the two ports are disconnected. As a result, at least one of the two ports to be connected can be more exposed to the spool hole 41. In the illustrated example, the connection point of the second actuator port 46B to the spool hole 41 is not blocked by the second spool 70, but opens wide into the spool hole 41. That is, in addition to removing the above-mentioned connecting portion 90, by further increasing the separation distance LD between the first spool 60 and the second spool 70 to widen the space S, the pressure loss within the control valve 30 can be reduced. can be further significantly reduced.

In the embodiment described above, the control valve 30 includes a valve body 40 in which a spool hole 41 is provided, and a first spool 60 and a second spool 70 that are movably provided in the spool hole 41 of the valve body 40. ,have. According to such a control valve 30, when connecting two ports communicating with the spool hole 41 via the spool hole 41, the first spool 60 and the second spool 70 are separated from each other within the spool hole 41. be able to. Therefore, the first spool 60 and the second spool 70 can be moved out of the region of the spool hole between the opening positions (connection positions) of the two ports to be connected to the spool hole 41. This reduces the cross-sectional area due to the narrow width (thin diameter) portion 90 (see FIG. 3) of the spool remaining in the region connecting the two ports of the spool hole 41, and reduces friction on the surface of the portion 90. can be avoided. As a result, pressure loss at the control valve 30 can be effectively reduced.

Further, in the embodiment described above, the control valve 30 includes the spool hole 41 and at least the first port (second supply port) 47B, the second port (second discharge port) 48B, and the common port communicating with the spool hole 41. The valve body provided with the (second actuator port) 46B and the spool hole 41 of the valve body 40 are movable, and the first port (second supply port) 47B and the common port (second supply port) are connected via the spool hole 41. The first spool 60 is movable, and the spool hole 41 of the valve body 40 is movable, allowing connection between the second port (second discharge port) 48B and the common port (second actuator port) 46B. It has a second spool 70 that allows connection of the second spool 70. According to such a control valve 30, when connecting two ports communicating with the spool hole 41 via the spool hole 41, the first spool 60 and the second spool 70 are separated from each other within the spool hole 41. be able to. Therefore, the first spool 60 and the second spool 70 can be moved out of the area of the spool hole 41 between the opening positions (connection positions) to the spool hole 41 of the two ports to be connected. This reduces the cross-sectional area due to the narrow width (thin diameter) portion 90 (see FIG. 3) of the spool remaining in the region connecting the two ports of the spool hole 41, and reduces friction on the surface of the portion 90. can be avoided. As a result, pressure loss at the control valve 30 can be effectively reduced.

In one specific example of the embodiment described above, the first spool 60 and the second spool 70 move asynchronously. That is, the first spool 60 and the second spool 70 can be moved independently. According to such an example, pressure loss can be reduced more effectively.

In one specific example of the embodiment described above, the separation distance LD between the first spool 60 and the second spool 70 when two ports (for example, the second actuator port 46B and the second supply port 47B) are connected is longer than the separation distance LD between the first spool 60 and the second spool 70 with the two ports disconnected. According to such an example, pressure loss can be more effectively reduced when connecting two ports. Further, when disconnecting the two ports, unintentional leakage of pressure oil can be effectively prevented.

In one specific example of the embodiment described above, the control valve 30 has a first back pressure chamber 42A communicating with the spool hole 41 through a first through hole 61 provided in the first spool 60, and a second spool 70. A second back pressure chamber 42B communicating with the spool hole 41 through a second through hole 71 provided therein. According to such an example, the driving force required to drive the first spool 60 can be significantly reduced. Furthermore, the driving force required to drive the second spool 70 can be significantly reduced. Thereby, the configuration of the control valve 30 can be simplified and the control valve 30 can be made smaller and lighter.

In one specific example of the embodiment described above, when the first spool 60 moves to one side (for example, from the state shown in FIG. 2 to the state shown in FIG. SB), the second spool 70 also moves to one side, while the first spool 60 moves to the other side (e.g. from the state shown in FIG. 4), the second spool 70 is stationary. According to such an example, the configuration and control for driving the second spool 70 can be simplified. Furthermore, by moving only the first spool 60 while keeping the second spool 70 stationary, it is possible to secure a large flow path for pressure oil formed by the space S, thereby reducing pressure loss more effectively. It is also possible to reduce the amount.

In one specific example of the embodiment described above, the control valve 30 includes a movement control section (pressure oil supply control section, An example having a pressure oil supply control valve (pressure oil supply control valve) 80 is shown. Both the movement of the first spool 60 and the movement of the second spool 70 are controlled by one movement control section 80. According to such an example, since the positions of the first spool and the second spool can be controlled by one drive unit (pressure oil supply control unit, pressure oil supply control valve) 80, the directional switching valve can be made smaller and lighter. It is possible to aim for

Although one embodiment has been described with reference to specific examples, it is not intended that the specific examples described above limit the embodiment. The embodiment described above can be implemented in various other specific examples, and various omissions, substitutions, changes, and additions can be made without departing from the gist thereof.

Hereinafter, an example of the modification will be described with reference to the drawings. In the following explanation and the drawings used in the following explanation, the same reference numerals as those used for corresponding parts in the above specific example are used for parts that may be configured in the same way as in the above specific example, and redundant explanations are used. omitted.

First, when the first spool 60 and the second spool 70 move to either side in the axial direction AD, they may be moved synchronously. According to such an example, pressure loss can be effectively reduced with simple control and configuration.

Specifically, the control valve 30 may be configured as follows. First, the second positioning means 56B further includes a second one-side pushing member in the second one-side chamber 43BX in addition to the second other-side pushing member 57BY. This second first side pushing member is arranged between the valve body 40 and the second first side shoulder 74X of the second spool 70, and pushes the second spool 70 in the axial direction AD via the second first side shoulder 74X. Push it to the other side SB. The second spool 70 in the neutral position is arranged in a position where the force from the second other side pushing member 57BY and the force from the second one side pushing member are balanced, and both sides in the axial direction AD from the neutral position can be moved to.

Further, the movement control unit 80 also switches the supply and stop of the supply of pilot pressure oil to the second other side chamber 43BY in addition to the second first side chamber 43BX. Specifically, the second other side passage 44BY leading to the second other side chamber 43BY may be connected to the first other side passage 44AY leading to the first other side chamber 43AY. According to this example, when the pilot pressure oil is supplied to the first other side chamber 43AY under the control of the movement control unit 80, the pilot pressure oil is also supplied to the second other side chamber 43BY. Further, when the supply of the pilot pressure oil to the first other side chamber 43AY is stopped under the control of the movement control unit 80, the supply of the pilot pressure oil to the second other side chamber 43BY is also stopped.

According to such an example, the first spool 60 and the second spool 70 can be moved synchronously. According to this example, pressure loss can be effectively reduced with simple control and configuration.

Furthermore, in the above-described example, one movement control section 80 controls both the movement of the first spool 60 and the movement of the second spool 70. However, the present invention is not limited to this example, and the direction switching valve 30 separately controls the first movement control section 80A that controls the movement of the first spool 60 and the second movement control section 80B that controls the movement of the second spool 70. It may be made to have. According to this example, the movements of the first spool 60 and the second spool 70 can be independently controlled. Therefore, pressure loss can be reduced more effectively.

As an example of such a modification, the control valve 30 shown in FIG. 80A and a second movement control section (second pressure oil supply control section) 80B that controls the supply of pilot pressure oil for driving the second spool 70 may be provided separately. According to such an example, the movement of the first spool 60 and the second spool 70 can be independently controlled with a simple configuration and simple control.

In the example shown in FIG. 5, the first movement control section 80A and the second movement control section 80B may be configured, for example, by a switching valve that switches the flow path, similarly to the movement control section 80 described above. For example, in the state shown in FIG. 6, both the first spool 60 and the second spool 70 are moved from the neutral state shown in FIG. 2 to the other side SB along the axial direction AD. However, the amount of movement of the second spool 70 toward one side SA along the axial direction AD is longer than the amount of movement of the first spool 60 toward one side SA along the axial direction AD. As a result, the separation distance LD in the axial direction AD of the first spool 60 and the second spool 70 in the state of FIG. 6 in which the two ports (second actuator port 46B and second discharge port 48B) are connected is The distance LD is longer than the distance LD between the first spool 60 and the second spool 70 in the state shown in FIG. 2 with the ports disconnected. According to such an example, pressure loss can be reduced more effectively. Note that the position of the first spool 60 in FIG. 6 is the same as the position of the first spool 60 in FIG. The position is the same as that of the second spool 70. The separation distance LD in the axial direction AD of the first spool 60 and the second spool 70 in the state of FIG. 3 in which the two ports (second actuator port 46B and second discharge port 48B) are connected is The distance LD is the same as the separation distance LD between the first spool 60 and the second spool 70 in the state shown in FIG. 2 in which the connection is interrupted.

On the other hand, in the control valve 30 shown in FIG. 5, when moving the first spool 60 to one side SA along the axial direction AD, the second movement control section 80B operates as in the example shown in FIG. The second spool 70 may remain stationary, or the second spool 70 may be moved toward one side SA along the axial direction AD by a smaller amount of movement than the first spool 60.

By the way, depending on the type of actuator to be driven, the supply and discharge of pressure oil to the actuator is controlled by a control method called a single-acting type, a hammer type, or the like. In a normal control method, both the supply of pressure oil to the actuator and the discharge of pressure oil from the actuator are performed simultaneously through two passages within one control valve. The amount of pressure oil supplied to the actuator and the amount of pressure oil discharged from the actuator are balanced by controlling a proportional valve that drives the spool. However, in control methods called single acting or hammer type, pressure oil is supplied to the actuator by driving the spool as usual, but the pressure oil discharge path from the actuator is fully opened or a certain amount is opened. maintained in condition. For example, in mechanical equipment such as a hammer, pressure oil is discharged when the pressure of the supplied pressure exceeds a predetermined value. Therefore, the amount of pressure oil supplied to the actuator via the control valve and the amount of pressure oil discharged are significantly different. If such pressure oil is discharged from the control valve, there is a possibility that the control valve will be damaged. Therefore, in control methods called single-acting type, hammer type, etc., it is necessary to separately provide a dedicated discharge path that does not pass through the control valve, which complicates the hydraulic circuit and increases the size of the hydraulic equipment.

On the other hand, this embodiment is also extremely suitable for such control methods called single-acting type, hammer type, and the like. For example, as shown in FIG. 6, by controlling the position of the first spool 60, the amount of pressure oil supplied to the actuator 18 can be controlled. On the other hand, by maintaining the second spool 70 in a predetermined position, for example, by maintaining the second spool 70 in a position where the second discharge port 48B is fully opened, regardless of the position of the first spool 60. A pressure oil discharge path that can always discharge a predetermined amount of pressure oil can be secured within the control valve 30. Therefore, it is possible to simplify the hydraulic circuit 20 and reduce the size and weight of the hydraulic equipment 15 by eliminating the need to provide a separate discharge path.

Furthermore, in the above-described specific example, an example in which the movement control units 80, 80A, and 80B are configured using a pressure oil supply control unit (for example, a pressure oil supply control valve) that switches between supplying and stopping the supply of pilot pressure oil is assumed. Although shown, the present invention is not limited to this example, and other means such as a motor may be used.

Furthermore, in the example described above, an example has been shown in which both the first spool 60 and the second spool 70 are arranged within the linear spool hole 41. In this example, a portion of the first spool 60 and a portion of the second spool 70 may be located at the same position within the spool hole 41. However, the present invention is not limited to the examples described above. For example, as shown in FIGS. 7 and 8, the first spool 60 may be movable within the first spool hole 41A, and the second spool 70 may be movable within the second spool hole 41B. In the example shown in FIGS. 7 and 8, the central axis CA1 of the first spool hole 41A and the central axis CA2 of the second spool hole 41B are offset and are not located on a straight line.

In the example shown in FIGS. 7 and 8, the control valve 30 includes a first spool hole 41A, a first port (second supply port 47B) communicating with the first spool hole 41A, a second spool hole 41B and a second A valve body 40 provided with a second port (second discharge port 48B) communicating with the hole 41B, and a common port (second actuator port 46B) communicating with the first spool hole 41A and the second spool hole 41B, and the valve body. 40 first spool holes 41A can be moved, and the first spool 60 can connect the first port (second supply port 47B) and common port (second actuator port 46B) via the first spool hole 41A. and a second spool 70 that is movable through the second spool hole 41B of the valve body 40 and that can connect the second port (second discharge port 48B) and common port (second actuator port 46B). are doing. This control valve 40 can also provide the same effects as those of the above-described embodiment.

Although several modifications to the embodiment described above have been described above, it is of course possible to apply a plurality of modifications in combination as appropriate.

10 Construction machinery 15 Hydraulic equipment 20 Hydraulic circuit 30 Control valve 40 Valve body 40
41, 41A, 41B Spool hole 42A First back pressure chamber 42B Second back pressure chamber 46A First actuator port 46B Second actuator port 47A First supply port 47B Second supply port 48A First discharge port 48B Second discharge port 60 First spool 70 Second spool 80 Movement control section 80A First movement control section 80B Second movement control section

Claims (10)

a valve body provided with a spool hole and at least a first port, a second port, and a common port communicating with the spool hole;
a first spool that is movable through the spool hole of the valve body and connectable to the first port and the common port via the spool hole;
a second spool that is movable in the spool hole of the valve body and that allows connection of the second port and the common port;
Equipped with
A control valve in which the first spool and the second spool move synchronously . A first spool hole and a first port communicating with the first spool hole, a second spool hole and a second port communicating with the second spool hole, and a common port communicating with the first spool hole and the second spool hole. a valve body provided;
a first spool that is movable in the first spool hole of the valve body and that is capable of connecting the first port and the common port via the first spool hole;
a second spool that is movable in the second spool hole of the valve body and that is capable of connecting the second port and the common port;
Equipped with
A control valve in which the first spool and the second spool move synchronously . Claim: When the first port and the common port are connected, the separation distance between the first spool and the second spool is longer than when the first port and the common port are disconnected. 3. The control valve according to 1 or 2 . a valve body provided with a spool hole and at least a first port, a second port, and a common port communicating with the spool hole;
a first spool that is movable through the spool hole of the valve body and connectable to the first port and the common port via the spool hole;
a second spool that is movable in the spool hole of the valve body and that allows connection of the second port and the common port;
a first back pressure chamber that communicates with the spool hole through a through hole provided in the first spool; a second back pressure chamber that communicates with the spool hole through a through hole provided in the second spool; A control valve comprising : The control valve according to any one of claims 1 to 4 , comprising a first movement control section that controls movement of the first spool, and a second movement control section that controls movement of the second spool. A first movement control section that controls supply of pilot pressure oil for driving the first spool, and a second movement control section that controls supply of pilot pressure oil for driving the second spool. The control valve according to any one of claims 1 to 5 . when the first spool moves to one side, the second spool also moves to one side;
A control valve according to any preceding claim, wherein the second spool is stationary when the first spool moves to the other side. A hydraulic circuit comprising the control valve according to any one of claims 1 to 7 . A hydraulic circuit according to claim 8 ;
A hydraulic device comprising: an actuator controlled by the hydraulic circuit. A construction machine comprising the hydraulic circuit according to claim 8 .