JP7514868B2 - Directional valve - Google Patents

Description

The present invention relates to a directional control valve installed in a work vehicle.

A known example of a work vehicle driven by a fluid at a predetermined pressure (hereinafter sometimes simply referred to as "fluid") is an excavator that has a running device with a pair of left and right crawlers, a vehicle body that is rotatably mounted on the running device, and a work device with a detachable attachment (e.g., a bucket, breaker, etc.) attached to an arm at the front of the vehicle body.

Examples of the drive control mechanism of the above-mentioned work vehicle include a hydraulic pump that supplies fluid (specifically, pressure oil), a hydraulic motor that operates the vehicle body's rotation mechanism, and a hydraulic cylinder that operates the arm and attachment. In addition, a directional control valve is provided to control the supply and discharge of pressure oil supplied from the hydraulic pump to the hydraulic motor and hydraulic cylinder (see Patent Document 1: JP 2003-278706 A).

When changing attachments to suit the type of work being performed on the above-mentioned work vehicle, because typical attachments are heavy, attaching and detaching them manually requires a great deal of effort. For this reason, a technology has been developed in which a quick hitch mechanism for attaching and detaching attachments is provided at the tip of the arm, and the supply and discharge of pressure oil supplied to the hydraulic cylinder that operates this mechanism is controlled by a directional control valve, switching the attachment between a locked state (non-replaceable state) and a released state (replaceable state) (see Patent Document 2: JP 2004-036635 A).

JP 2003-278706 A JP 2004-036635 A

As mentioned above, directional control valves are widely used in the mechanisms that control the drive of work vehicles. Therefore, if these directional control valves were designed and manufactured individually for each device to be controlled, it would lead to an increase in the number of dies in the casting process, and the machining process would become more complicated and the number of steps would increase, causing manufacturing costs to rise. Furthermore, if multiple directional control valves were installed independently, it would require more installation space, causing the vehicle itself to become larger.

The present invention was made in consideration of the above circumstances, and aims to provide a directional control valve that can reduce manufacturing costs by standardizing the casting mold through the use of a common housing, and that can also be made smaller and thinner and arranged in a multi-layered configuration.

In one embodiment, the above problem is solved by the solution disclosed below.

The disclosed directional control valve is a directional control valve arranged in a work vehicle, and includes a first section that controls the operation of a first actuator for a first operating device, and an inlet that is connected to the first section and has a main pump port and a sub-pump port. The first section is provided with a first port that communicates with one side of the first actuator and supplies and discharges fluid supplied from the main pump port, and a second port that communicates with the other side of the first actuator and supplies and discharges fluid supplied from the sub-pump port, and is housed in an internal spool hole so as to be axially movable and is connected to the first port and the sub-pump port. The pump has a first housing provided with a spool that selectively switches between the supply from the second port and stops the flow, the inlet is stacked on a first surface of the first housing where the first port and the second port are not provided, the first housing is connected to an outlet that communicates with the sub-pump port of the inlet, and an inlet that communicates with the second port through the spool hole is formed on the first surface, and the spool has a supply flow path drilled therein that can communicate with a flow path that communicates with the spool hole and the inlet, and a flow path that communicates with the spool hole and the second port.

Here, the second section is connected to the first section and controls the operation of a second actuator for a second operating device, and the second section has a second housing provided with a third port that communicates with one side of the second actuator and supplies and discharges the fluid supplied from the main pump port, and a fourth port that communicates with the other side of the second actuator and supplies and discharges the fluid supplied from the main pump port, and the second housing is preferably stacked on a second surface of the first housing that is parallel to and opposite to the first surface. It is also preferable that the first housing and the second housing are made of a casting material cast in the same mold. It is also preferable that the first housing and the second housing each have a relief port installation area on both or one of the fifth and sixth surfaces that are side surfaces. It is also preferable that a filter is disposed deep inside the sub-pump port of the inlet. The first operating device can be suitably applied to a configuration in which the first operating device is a quick hitch mechanism and the first actuator is a hydraulic cylinder.

The disclosed directional control valve allows for a reduction in manufacturing costs by standardizing the casting mold through the use of a common housing. It also allows for a smaller, thinner housing and multiple stacked arrangement.

1 is a plan view illustrating an example of a directional control valve according to an embodiment of the present invention. FIG. 2 is a front view of the directional control valve shown in FIG. 1 . 3 is a cross-sectional view taken along line III-III in FIG. 1. 4 is a cross-sectional view taken along line IV-IV in FIG. 2. 3 is a cross-sectional view taken along line VV in FIG. 2. 2 is a partial circuit diagram of a work vehicle equipped with the directional control valve shown in FIG. 1 .

The embodiment of the present invention will be described in detail below with reference to the drawings. FIG. 1 is a plan view (schematic diagram) showing an example of a directional control valve 1 according to this embodiment, and FIG. 2 is a front view (schematic diagram) thereof. FIG. 3 is a cross-sectional view taken along line III-III in FIG. 1, and FIG. 4 and FIG. 5 are cross-sectional views taken along line IV-IV and line V-V in FIG. 2, respectively. FIG. 6 is a partial circuit diagram of a work vehicle equipped with a directional control valve 1 according to this embodiment, but this is only one example of the configuration and is not limited to this. In all drawings for explaining the embodiment, members having the same function are given the same reference numerals, and repeated explanations of such members may be omitted. For convenience, the "top", "bottom", "front", "back", "left side" and "right side" of each member will be described according to the display position in FIG. 2, but this does not necessarily stipulate the arrangement (mounting orientation) on the work vehicle.

The directional control valve 1 according to this embodiment, for example, controls the operation of a hydraulic cylinder that operates a quick hitch mechanism in a work vehicle (not shown) or a hydraulic motor that operates a vehicle body turning mechanism, and more specifically, controls the supply and discharge of fluid used to operate the hydraulic cylinder or hydraulic motor, i.e., controls switching and stopping of the flow direction.

More specifically, as shown in Figures 2 and 6, the directional control valve 1 is configured by connecting an inlet 2 that receives fluid (pressurized oil) at a predetermined pressure supplied from external supply sources (hydraulic pumps described below) Pm and Ps and allows the fluid to flow out to a tank T, a first section 3 that controls the operation of a first actuator that operates a first actuator (i.e., controls the supply and discharge of fluid), a second section 4 that controls the operation of a second actuator that operates a second actuator (i.e., controls the supply and discharge of fluid), and a cover 5 that seals the opening of an unused flow path exposed on the underside of the lowest section (in this embodiment, second section 4).

In this embodiment, a quick hitch mechanism (not shown) is used as the first actuator, and a vehicle body rotation mechanism (not shown) is used as the second actuator. In this case, a hydraulic cylinder C is used as the first actuator, and a hydraulic motor SM is used as the second actuator. However, this is not limited to these configurations. For example, the second actuator may be an arm or an attachment (a bucket or breaker, for example), in which case a hydraulic cylinder is used as the second actuator (neither is shown).

First, the inlet 2 will be described. In the inlet 2 according to this embodiment, a sub-pump port 16 is provided on the first surface (upper surface) 2a, through which a fluid of a predetermined pressure (for example, about 3.5 MPa) delivered from the sub-hydraulic pump Ps, which is an external supply source, flows in. A main pump port 15 is provided on the third surface (front surface) 2c, through which a fluid of a predetermined pressure (for example, about 25 MPa) delivered from the main hydraulic pump Pm, which is an external supply source, flows in. Furthermore, a tank port 19 is provided on the third surface (front surface) 2c, through which a fluid used to operate the hydraulic cylinder C, etc., is delivered to a tank T. An outlet 25 is provided on the second surface (lower surface) 2b of the inlet 2, which is connected to the sub-pump port 16 via a first sub-pump flow path 23A.

The sub-pump port 16 of the inlet 2 has a filter (specifically, an oil filter) 50 disposed deep inside. If a mechanism for disposing the filter were to be provided in the first housing 11 of the first section 3 described below, the size of the first housing 11 would become larger, for example in the left-right direction. On the other hand, it is also possible to incorporate the filter into the connector connected to the sub-pump port 16 rather than providing it in the first housing 11, but a connector with a built-in filter would increase the parts cost. In contrast, the above configuration makes it possible to prevent the size of the first housing 11 from becoming larger and also suppresses increases in parts costs.

Next, the first section 3 will be described. The first section 3 according to this embodiment is configured with a housing (first housing) 11 and a drive unit 30 provided on a side of the first housing 11 (for example, the fifth surface (left side surface) 11e). The first housing 11 is provided with a first port 17A that allows the fluid supplied from the main hydraulic pump Pm to flow into and out of one side (for example, the rod chamber side) of the hydraulic cylinder C via a spool hole 20A (described later), and a second port 17B that allows the fluid supplied from the sub hydraulic pump Ps to flow into and out of the other side (for example, the anti-rod chamber side) of the hydraulic cylinder C via the spool hole 20A. In addition, a main flow path 13 that allows the fluid supplied from the main hydraulic pump Pm to flow is provided. Here, the first surface (top surface) 11a of the first housing 11 is provided with an inlet 26 (i.e., an end of the second sub-pump flow path 23B) that communicates with the spool hole 20A via the second sub-pump flow path 23B, and an upper surface opening 13a of the main flow path 13. As an example, the first port 17A and the second port 17B are configured to be provided on the third surface (front surface) 11c, but may also be configured to be provided on the fourth surface (rear surface) 11d (not shown).

In this embodiment, the inlet 2 is stacked and connected to a surface of the first housing 11 on which the first port 17A and the second port 17B are not provided (for example, the first surface (upper surface) 11a). That is, the second surface (lower surface) 2b of the inlet 2 and the first surface (upper surface) 11a of the first housing 11 are connected in contact with each other. At this time, the outlet 25 of the inlet 2 and the inlet 26 of the first housing 11 are connected to allow the flow of fluid.

The first housing 11 is provided with a spool hole 20A, which is a cylindrical space that communicates with the first port 17A, the second port 17B, and each port of the connected inlet 2 (the main pump port 15, the sub pump port 16, and the tank port 19). The first housing 11 is further provided with a first flow path 27A that communicates with the spool hole 20A and the first port 17A, and a second flow path 27B that communicates with the spool hole 20A and the second port 17B.

In addition, a spool 21A is provided within the spool hole 20A, which is housed axially movable (more specifically, slidable with a predetermined fit tolerance) to control the supply and discharge of fluid. As an example, the spool hole 20A and the spool 21A are formed with a circular cross section, and the spool hole 20A is formed penetrating from one side surface of the first housing 11 to the other side surface. Although not shown, the outer peripheral surface of the spool 21A is provided with a notch that connects predetermined flow paths when the spool 21A is driven (moved) to a predetermined position (control position).

In addition, in the spool 21A according to this embodiment, when it is driven (moved) to a predetermined position (control position) in the spool hole 20A, a supply flow path 22 is drilled inside so that the second sub-pump flow path 23B, which is a flow path that communicates the spool hole 20A with the inlet 26, and the second flow path 27B, which is a flow path that communicates the spool hole 20A with the second port 17B, are in a communication state, allowing the flow of fluid.

According to the above configuration, the drive unit 30 drives (moves) the spool 21A in the axial direction within the spool hole 20A, thereby allowing selective switching between supplying fluid from the first port 17A and supplying fluid from the second port 17B, and stopping the flow. As is clear from the circuit diagram in FIG. 6, when either the first port 17A or the second port 17B is in a supply state (outflow state), the other is in a discharge state (inflow state).

As described above, the drive unit 30 is disposed on the fifth surface (left surface) 11e of the first housing 11. As a specific configuration example, it is provided with a pressure chamber 32 that communicates with a sub-hydraulic pump (which may or may not be configured in common with the sub-hydraulic pump Ps described above) and applies fluid pressure to an end (here, the left end 21a) of the spool 21A in response to the operation of the operator. In addition, inside the pressure chamber 32, there is provided a spring chamber 36 in which a biasing member (for example, a coil spring) 38 is provided that applies a biasing force to the spool 21A in the opposite direction to the movement direction when the spool 21A moves from a predetermined position. Here, the reference numeral 37 in the figure is a transmission member that transmits the biasing force of the biasing member 38 to the spool 21A.

In operation with the above configuration, when the pressure applied to the pressure chamber 32 increases and the pressure acting on the left end 21a of the spool 21A exceeds the above-mentioned biasing force, the spool 21A is driven (moved) to the right. On the other hand, when the pressure applied to the pressure chamber 32 decreases and the pressure acting on the left end 21a of the spool 21A falls below the above-mentioned biasing force, the spool 21A is driven (moved) to the left.

Here, when the pressure is applied to the pressure chamber 32 and the spool 21A is driven (moved) to the right, the main flow path 13 and the first flow path 27A are in communication with each other. Therefore, a fluid of a predetermined pressure (for example, about 25 MPa) supplied from the main pump port 15 is supplied from the first port 17A to one side (for example, the rod chamber side) of the hydraulic cylinder C, and the rod is operated (moved) in the direction of contraction. As a result, the hook in the quick hitch mechanism, which is the first operating device, is released, and the attachment can be replaced. In this embodiment, when the above state is reached, the flow of fluid from the first housing 11 to the second housing 12 below is blocked, and malfunction in the second section 4 is prevented. Therefore, the stacking order of each section according to this embodiment is suitable.

On the other hand, when the above pressure is not applied to the pressure chamber 32, the spool 21A is stopped at a predetermined position (a position moved to the left). At this time, the second sub-pump flow path 23B and the second flow path 27B are in communication. Therefore, fluid at a predetermined pressure (for example, about 3.5 MPa) supplied from the sub-pump port 16 is supplied from the second port 17B to the other side (for example, the side opposite the rod chamber) of the hydraulic cylinder C, and the rod is maintained in an extended state. This keeps the hook in the quick hitch mechanism engaged, and keeps it impossible to replace the attachment.

Next, the second section 4 will be described. The second section 4 according to this embodiment is configured to include a housing (second housing) 12, a drive unit 40A provided on one side of the second housing 12 (for example, the fifth side (left side) 12e), and a drive unit 40B provided on the other side of the second housing 12 (for example, the sixth side (right side) 12f). The second housing 12 is provided with a third port 18A that allows the fluid supplied from the main hydraulic pump Pm to flow into and out of one side of the hydraulic motor SM (for example, the left turning input side) via a spool hole 20B (described later), and a fourth port 18B that allows the fluid supplied from the main hydraulic pump Pm to flow into and out of the other side of the hydraulic motor SM (for example, the right turning input side) via the spool hole 20B. In addition, a main flow path 14 that allows the fluid supplied from the main hydraulic pump Pm to flow is provided. Here, the first surface (top surface) 12a of the second housing 12 is provided with an upper surface opening 14a of the main flow passage 14. As an example, the third port 18A and the fourth port 18B are configured to be provided on the third surface (front surface) 12c, but they may also be configured to be provided on the fourth surface (back surface) 12d (not shown).

Here, in this embodiment, the second section 4 is stacked and connected to the second surface (lower surface) 11b (in other words, a surface parallel to and opposite to the first surface 11a) of the first housing 11 of the first section 3. That is, the second surface (lower surface) 11b of the first housing 11 and the first surface (upper surface) 12a of the second housing 12 are connected in abutting contact. At this time, the main flow passage 13 (specifically, the lower surface opening 13b) of the first housing 11 and the main flow passage 14 (specifically, the upper surface opening 14a) of the second housing 12 are connected to enable the flow of fluid supplied from the main hydraulic pump Pm. Note that when the second section 4 is the bottom layer, the lower surface opening 14b of the main flow passage 14 is not used and is sealed by the cover 5.

The second housing 12 is provided with a third port 18A, a fourth port 18B, and a spool hole 20B, which is a cylindrical space that communicates with a predetermined flow path in the connected first housing 11. The second housing 12 is further provided with a third flow path 28A that communicates with the third port 18A and the spool hole 20B, and a fourth flow path 28B that communicates with the fourth port 18B and the spool hole 20B.

In addition, a spool 21B is provided that is housed within the spool hole 20B so as to be movable in the axial direction (more specifically, so as to be slidable with a predetermined fit tolerance) and controls the supply and discharge of fluid. As an example, the spool hole 20B and the spool 21B are formed with a circular cross section, and the spool hole 20B is formed through the second housing 12 from one side to the other side. Although not shown, the outer peripheral surface of the spool 21B is provided with a notch that connects predetermined flow paths when the spool 21B is driven (moved) to a predetermined position (control position). However, unlike the spool 21A, no supply flow path is drilled inside.

According to the above configuration, by driving (moving) the spool 21B in the axial direction within the spool hole 20B using the drive units 40A and 40B, it is possible to selectively switch between supplying fluid from the third port 18A and supplying fluid from the fourth port 18B, increase or decrease the outflow rate, and stop the flow. As is clear from the circuit diagram in FIG. 6, when either the third port 18A or the fourth port 18B is in a supply state (outflow state), the other is in a discharge state (inflow state).

As described above, the drive unit 40A is disposed on the fifth surface (left side surface) 12e of the second housing 12, and the drive unit 40B is disposed on the sixth surface (right side surface) 12f. As a specific configuration example, the drive unit 40A is connected to a sub-hydraulic pump (which may be configured either in common or not in common with the sub-hydraulic pump Ps described above) and has a pressure chamber 42A that applies fluid pressure to the end of the spool 21B (here, the left end 21c) in response to the operator's operation. On the other hand, the drive unit 40A is connected to a sub-hydraulic pump (which may be configured either in common or not in common with the sub-hydraulic pump Ps described above) and has a pressure chamber 42B that applies fluid pressure to the end of the spool 21B (here, the right end 21d) in response to the operator's operation.

The pressure chamber 42A also includes a spring chamber 46 in which a biasing member (a coil spring, for example) 48 is provided that applies a biasing force to the spool 21B in the opposite direction to the direction of movement of the spool 21B when the spool 21B moves from the neutral position. Here, reference numeral 47 in the figure denotes a transmission member that transmits the biasing force of the biasing member 48 to the spool 21B. In this embodiment, a single biasing member 48 generates a biasing force in the opposite direction when the spool 21B moves to the left or right. However, this is not limited to this, and as a modified example, a spring chamber may also be provided inside the pressure chamber 42B, and the biasing force may be shared between the two (not shown).

In the operation of the above configuration, when the pressure applied to the pressure chamber 42A increases and the pressure acting on the left end 21c of the spool 21B exceeds the above-mentioned biasing force, the spool 21B is driven (moved) to the right. On the other hand, when the pressure applied to the pressure chamber 42A decreases and the pressure acting on the left end 21c of the spool 21B falls below the above-mentioned biasing force, the spool 21B is driven (moved) to the left. Similarly, when the pressure applied to the pressure chamber 42B increases and the pressure acting on the right end 21d of the spool 21B exceeds the above-mentioned biasing force, the spool 21B is driven (moved) to the left. On the other hand, when the pressure applied to the pressure chamber 42B decreases and the pressure acting on the right end 21d of the spool 21B falls below the above-mentioned biasing force, the spool 21B is driven (moved) to the right. In this embodiment, proportional control is performed.

When the pressure is applied to the pressure chamber 42A and the spool 21B is driven (moved) to the right, the main flow path 13 and the third flow path 28A are connected to each other. Therefore, fluid at a predetermined pressure (for example, about 25 MPa) supplied from the main pump port 15 is supplied from the third port 18A to one side of the hydraulic motor SM (for example, the left turning input side), causing the hydraulic motor to rotate. This activates the turning mechanism and causes the vehicle body to turn (in this case, turn left).

On the other hand, when the above pressure is applied to the pressure chamber 42B and the spool 21B is driven (moved) to the left, the main flow path 13 and the fourth flow path 28B are connected to each other. Therefore, fluid at a predetermined pressure (approximately 25 MPa as above) supplied from the main pump port 15 is supplied from the fourth port 18B to the other side of the hydraulic motor SM (as an example, the right turning input side), causing the hydraulic motor to rotate. This activates the turning mechanism and causes the vehicle body to turn (in this case, turn right).

As described above, the directional control valve 1 according to this embodiment has the following remarkable effects by being equipped with various components that are provided in a composite manner, in particular a component in which a supply passage 22 is drilled inside the spool 21A, and a component in which the fluid supplied from the sub-hydraulic pump Ps flows into the first housing 11 from the inlet 26 on the first surface (upper surface) 11a on which the inlet 2 is stacked.

Specifically, in a configuration in which the inlet 2 is stacked (connected) on the first surface (upper surface) 11a of the housing (first housing 11) of the first section 3, and the housing (second housing 12) of the second section 4 is stacked (connected) on the second surface (lower surface) 11b, it is possible to realize a configuration in which the first housing 11 and the second housing 12 are formed from a casting material cast in the same mold (i.e., only some parts where openings, etc. are formed by machining are different). Therefore, since it is not necessary to configure only the first housing 11 on which the inlet 2 is stacked to be formed from a casting material cast in a dedicated mold, significant cost reductions are possible. Note that the "same mold" includes, for example, multiple molds formed in the same shape for the purpose of mass production.

Furthermore, depending on the specifications, a configuration can be realized in which housings of other sections are stacked (connected) on the second surface (lower surface) 12b of the housing of the second section 4 (second housing 12). In a similar manner, a configuration can be realized in which housings of multiple other sections are stacked (connected). In these cases, a configuration can be realized in which all housings are formed from casting material cast in the same mold, as above. Therefore, a directional control valve in which multiple housings, i.e., multiple sections, are arranged in a multi-layered configuration, can be realized at low cost.

In particular, the thickness dimension (the dimension in the direction sandwiched between the inlet 2 and the second housing 12) of the first housing 11 of the first section 3 in which the sub-pump flow path (second sub-pump flow path 23B) is provided can be made smaller (thinner). This makes it possible to reduce the size and thickness of the housing formed from a common casting material, and ultimately the entire directional control valve in which the housings are stacked.

Furthermore, in the first housing 11, a space without a flow path can be created between the first flow path 27A and the fifth surface (left side surface) 11e, and an area without a flow path can be created between the second flow path 27B and the sixth surface (right side surface) 11f. As a result, when it is necessary to install a relief port communicating with the first flow path 27A or the second flow path 27B according to the specifications of the work vehicle, the casting material of the first housing 11 can be used as is, and a configuration in which a relief port is installed on both the fifth surface (left side surface) 11e and the sixth surface (right side surface) 11f can be realized by simply adding a machining process (a configuration in which the relief port is installed only on the fifth surface (left side surface) 11e or only on the sixth surface (right side surface) 11f is also possible). Specifically, the relief port installation areas 24 (24A) and 24 (24B) can be provided at the positions shown in FIG. 4 (note that the relief port is already installed on the fifth surface (left side surface) 11e side). Similarly, in the second housing 12, a space without a flow path can be created between the third flow path 28A and the fifth surface (left side surface) 12e, and an area without a flow path can be created between the fourth flow path 28B and the sixth surface (left side surface) 12f. As a result, when it is necessary to install a relief port communicating with the third flow path 28A or the fourth flow path 28B according to the specifications of the work vehicle, the casting material of the second housing 12 can be used as is, and a configuration in which relief ports are installed on both the fifth surface (left side surface) 12e and the sixth surface (right side surface) 12f can be realized by simply adding a machining process (a configuration in which relief ports are installed only on the fifth surface (left side surface) 12e or only on the sixth surface (right side surface) 12f is also possible). Specifically, relief port installation areas 24 (24C), 24 (24D) can be provided at the positions shown in FIG. 5.

As explained above, the disclosed directional control valve makes it possible to reduce manufacturing costs by standardizing the casting mold through the use of a common housing. It also makes it possible to make the housing smaller and thinner and to arrange it in multiple layers.

It goes without saying that the present invention is not limited to the above-described embodiment, and various modifications are possible without departing from the scope of the present invention. As an example, a configuration has been described in which the second actuator is a vehicle body turning mechanism, and the second section is a section that controls the operation of a hydraulic motor, but the present invention is not limited to this. In other words, a configuration in which the second actuator is an arm or attachment, etc., and the second section is a section that controls the operation of a hydraulic cylinder is also possible.

Furthermore, it is also possible to stack (connect) one or more other sections underneath the second section. Alternatively, it is also possible to omit the second section.

REFERENCE SIGNS LIST 1 directional control valve 2 inlet 3 first section 4 second section 11 first housing 12 second housing 15 main pump port 16 sub pump port 17A first port 17B second port 18A third port 18B fourth port 20A, 20B spool holes 21A, 21B spool 22 supply flow passage 24 relief port installation area 25 outlet 26 inlet 50 filter

Claims (7)

A directional control valve provided in a work vehicle,
a first section for controlling actuation of a first actuator for a first actuation device;
an inlet connected to the first section and having a main pump port and a sub pump port;
the first section has a first port communicating with one side of the first actuator to supply and discharge fluid supplied from the main pump port and a second port communicating with the other side of the first actuator to supply and discharge fluid supplied from the sub-pump port, and a spool accommodated in an internal spool hole so as to be axially movable and to selectively switch between supply from the first port and supply from the second port and to stop flow of fluid,
the inlet is stacked on a first surface of the first housing on which the first port and the second port are not provided,
the first housing has an outlet connected to the sub-pump port of the inlet, and an inlet formed in the first surface, the inlet communicating with the second port via the spool hole;
a supply passage formed inside the spool that can communicate with a passage communicating with the spool hole and the inlet, and a passage communicating with the spool hole and the second port. a second section coupled to the first section and configured to control actuation of a second actuator for a second actuation device;
the second section has a second housing provided with a third port communicating with one side of the second actuator to supply and discharge the fluid supplied from the main pump port and a fourth port communicating with the other side of the second actuator to supply and discharge the fluid supplied from the main pump port,
2. The directional control valve according to claim 1, wherein the second housing is laminated on a second surface of the first housing that is parallel to and faces in an opposite direction to the first surface. 3. The directional control valve according to claim 2, wherein the first housing and the second housing are made of a casting material cast in the same mold. 4. The directional control valve according to claim 2, wherein the first housing has a relief port installation area on both or one of a fifth surface and a sixth surface which are side surfaces. 4. The directional control valve according to claim 2, wherein the second housing has a relief port installation area on both or one of a fifth surface and a sixth surface which are side surfaces. 6. The directional control valve according to claim 1, wherein the first operating device is a quick hitch mechanism, and the first actuator is a hydraulic cylinder. 7. The directional control valve according to claim 1, further comprising a filter disposed at an innermost portion of the sub-pump port of the inlet.

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