JP2017141858A - Directional control valve and hydraulic system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a directional control valve improving a maintenance performance and a service performance of a spool type directional control valve comprising multiple regulation members, and a hydraulic system.SOLUTION: A directional control valve 30 comprises a valve body 31, a spool 80 and multiple regulation members (check valves 71-74 and the like). The valve body 31 includes a spool hole 33, a bridge passage 53 connected to the spool hole 33, and multiple supply passages 51 and 52 that are connectable to the bridge passage 53. The spool 80 is inserted into the spool hole 33, and the multiple regulation members (check valves 71-74 and the like) control a flow of a hydraulic fluid between each of the multiple supply passages 51 and 52 and the bridge passage 53. In the valve body 31, multiple passage holes 701-704 through which the multiple regulation members (check valves 71-74 and the like) can be passed are formed. The multiple passage holes 701-704 are opened on the same surface of the valve body 31.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a direction switching valve in which a regulating member is disposed between a bridge passage that opens in a spool hole and a supply passage of a working fluid, and a hydraulic system including such a direction switching valve.

  A valve device that controls the flow of a working fluid such as oil using a spool is known.

  For example, Patent Document 1 discloses a valve device configured by connecting a plurality of valve bodies. In this valve device, each communication path is connected in parallel via a check valve to a linear maximum pressure path that passes through all valve bodies connected to each other. Thereby, the load pressure on each communication passage side is guided to the highest pressure passage only when the pressure is higher than the pressure of the highest pressure passage, so that the highest pressure among the plurality of load pressures is guided to the highest pressure passage.

JP 2013-238291 A

  In the valve device disclosed in Patent Document 1 described above, the check valve is provided on the connection surface between the valve bodies. Therefore, in order to perform maintenance such as maintenance of the plurality of check valves or to replace the check valves with other functional parts (for example, blind plugs), the connection between the valve bodies must be broken.

  Therefore, in order to perform maintenance and service on the regulating member such as a check valve in the valve device disclosed in Patent Document 1, it is necessary to disassemble and reassemble the valve body, which is very inconvenient and time consuming. . In particular, when a plurality of restricting members such as check valves are provided in one directional switching valve, it may be required to perform maintenance or service only on a specific restricting member. In the valve device disclosed in Patent Literature 1, even when maintenance is performed on only one check valve, disassembly and reassembly of all valve bodies may be required.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a technique for improving the maintenance performance and service performance of a spool-type directional switching valve including a plurality of regulating members.

  One aspect of the present invention is a valve body having a spool hole, a bridge passage connected to the spool hole, a plurality of supply passages connectable to the bridge passage, a spool inserted into the spool hole, and a plurality of spools A plurality of restricting members that control the flow of the working fluid between each of the supply passages and the bridge passage, and the valve body is formed with a plurality of passage holes through which the plurality of restricting members can pass. The through hole relates to a direction switching valve that opens on the same surface of the valve body.

  The valve body may further include an actuator passage connected to the spool hole, and the actuator passage may be opened on the same surface as the surface of the valve body where the plurality of passage holes are opened.

  The plurality of passage holes may not be arranged on the same straight line when viewed from the surface of the valve body where the plurality of passage holes open.

  The plurality of supply passages may include passages having different functions.

  The plurality of supply passages may include a parallel-type passage and a tandem-type passage in connection with the working fluid supply source.

  Another aspect of the present invention relates to a hydraulic system including the direction switching valve, a working fluid supply source that communicates with a plurality of supply passages of the direction switching valve, and an actuator that communicates with an actuator passage of the direction switching valve.

  According to the present invention, since a plurality of passage holes through which a plurality of regulating members can pass open on the same surface of the valve body, a direction in which excellent maintenance performance and service performance can be exhibited with respect to the regulating members. A switching valve and a hydraulic system comprising such a directional switching valve can be provided.

FIG. 1 is a circuit diagram of a direction switching valve according to an embodiment of the present invention. FIG. 2 is a plan view (viewed from above) showing an example of a direction switching valve that realizes the circuit configuration shown in FIG. 3 is a cross-sectional view of the direction switching valve taken along line III-III in FIG. 4 is a cross-sectional view of the direction switching valve taken along line IV-IV in FIG. FIG. 5 is a cross-sectional view of the direction switching valve taken along line VV in FIG. FIG. 6 is a cross-sectional view of the direction switching valve taken along line VI-VI in FIG. FIG. 7 is a conceptual diagram showing a state in which the bridge passage and the like are viewed from the surface of the valve body where a plurality of passage holes are opened. FIG. 8 shows a circuit diagram of an example of a construction machine hydraulic circuit to which a plurality of directional control valves are applied.

  Embodiments of the present invention will be described with reference to the drawings.

  In the following embodiments, a spool-type direction switch provided with a “regulating member (for example, check valve, blind plug, etc.)” that controls the flow of hydraulic oil (working fluid) between each of the plurality of supply passages and the bridge passage. The valve will be exemplified. This directional switching valve may be a so-called monoblock type directional switching valve integrated with a main body, or may be a so-called sectional type directional switching valve with a separate main body. Therefore, for example, the present invention is directed to a directional control valve that adopts a monoblock type valve structure and has a check valve provided between each of a plurality of supply passages constituting a parallel circuit and / or a tandem circuit and a bridge passage. Effectively applicable.

  FIG. 1 is a circuit diagram of a direction switching valve 30 according to an embodiment of the present invention. FIG. 2 is a plan view (viewed from above) showing an example of the direction switching valve 30 for realizing the circuit configuration shown in FIG. 3 is a cross-sectional view of the direction switching valve 30 taken along line III-III in FIG. 4 is a cross-sectional view of the direction switching valve 30 taken along line IV-IV in FIG. FIG. 5 is a cross-sectional view of the direction switching valve 30 taken along line VV in FIG. 6 is a cross-sectional view of the direction switching valve 30 taken along line VI-VI in FIG.

  1 to 6 includes a valve body 31 in which a spool hole 33 is formed, a spool 80 inserted into the spool hole 33, and a plurality of passages (41, 42, 45, 51, 52, 53, 61, 62 (hereinafter also referred to as passages (41-62)), a plurality of regions (201, 202, 401, 402) that can form passages (101, 102, 301, 302), and a plurality of A plurality of regions (711-714) capable of forming passage holes (701-704) for providing a plurality of check valves (71-74) that can be arranged between each of the supply passages and the bridge passage 53; Prepare.

  The direction switching valve 30 is a direction switching valve applied to a construction machine hydraulic circuit (not shown). The directional control valve 30 is connected to, for example, a pump (not shown) and an actuator (not shown) in a hydraulic circuit for construction machinery, and is used to supply (discharge and supply) hydraulic oil from the pump to the actuator. It is a valve.

  The passages (101, 102, 301, 302) that can be formed in the above regions (201, 202, 401, 402) are passages for supplying hydraulic oil (discharge oil) discharged from the pump to the actuator. . The direction switching valve 30 supplies and discharges hydraulic oil to and from the actuator when a passage (101, 102, 301, 302) is formed in at least one of the plurality of regions (201, 202, 401, 402). (Supply and discharge).

  That is, it can be said that the direction switching valve 30 shown in FIGS. 1 to 6 is an intermediate body (base body and base member) for manufacturing a direction switching valve that is applied to a hydraulic circuit and appropriately switches the flow of hydraulic oil. This directional control valve 30 includes a plurality of regions (201, 202, 401, 402) as described above, thereby selectively forming a plurality of types of passage patterns for supplying hydraulic oil from the pump to the actuator. Is possible.

  The actuator to which the direction switching valve 30 is connected is a hydraulic actuator that operates the construction machine. The types of actuators to which the direction switching valve 30 can be connected include, for example, a hydraulic motor and a hydraulic cylinder. The actuator to which the direction switching valve 30 is connected is an actuator that includes a first port and a second port. Each of the first port and the second port is a hydraulic oil supply / discharge port (supply port and discharge port) to the actuator. Such an actuator operates on one side when hydraulic oil is supplied to the first port and hydraulic oil is discharged from the second port. Specifically, for example, the hydraulic cylinder extends, and for example, the hydraulic motor rotates to one side. When the hydraulic oil is supplied to the second port and the hydraulic oil is discharged from the first port, the actuator operates on the other side (the side opposite to the “one side”). Specifically, for example, the hydraulic cylinder contracts, and for example, the hydraulic motor rotates to the other side. The direction switching valve 30 is assumed to be connected to such an actuator via an actuator passage (61, 62) described later.

  This direction switching valve 30 is a spool valve that changes the direction in which the hydraulic oil flows in accordance with the axial position (stroke position; slide position) of the spool 80 in the spool hole 33. The switching position of the direction switching valve 30 is determined according to the stroke position of the spool 80, and switches between full opening, full opening, and partial opening (partial closing) of the opening that opens to the spool hole 33. The switching position of the direction switching valve 30 includes a neutral position 30a (see FIG. 1), a first operating position 30b (see the left side of the neutral position 30a in FIG. 1), and a second operating position 30c (neutral position 30a in FIG. 1). On the right side).

  The valve body 31 is a portion in which a plurality of passages (41 to 62) including a spool hole 33, a bridge passage 53 and a supply passage, regions (201, 202, 401, 402), and regions (711 to 714) are formed. . The valve body 31 of this example has a block-shaped (lumped) monoblock type valve structure, and a plurality of directional switching valves (spool valves) are formed with respect to a single valve body 31 as shown in FIG. Is done. Below, it demonstrates paying attention to one specific direction switching valve 30 (refer FIG. 2) among the several direction switching valves formed in the valve main body 31. FIG. The other direction switching valve formed in the valve body 31 may have the same configuration as the direction switching valve 30 described below, or may have another configuration.

  The spool hole 33 is formed inside the valve body 31. The spool hole 33 is a hole into which the spool 80 can be inserted. The spool 80 is detachably inserted into the spool hole 33.

  Each of the plurality of passages (41 to 62) is a flow path (oil path, piping) through which hydraulic oil flows. Each of the plurality of passages (41 to 62) is formed inside the valve body 31. Of the plurality of passages (41 to 62), the passages (41, 42, 45, 53, 55, 61, 62) open to the spool hole 33. The specific formation mode of the opening to the spool hole 33 of the passage (41, 42, 45, 53, 55, 61, 62) that opens to the spool hole 33 is not particularly limited. It may extend in the circumferential direction. The passages (41, 42, 45, 61, 62) among the plurality of passages (41 to 62) open to the surface of the valve body 31 so as to communicate with the outside of the valve body 31. Further, the passages (51, 52) among the plurality of passages (41-62) also open on the surface of the valve body 31 so as to communicate with the outside of the valve body 31. The plurality of passages (41 to 62) include an unload passage (41, 42), a tank passage 45, a supply passage (51, 52), a bridge passage 53, a bypass passage 55, and an actuator passage (61, 62). ) And.

  The unload passages (41, 42) are passages for returning the hydraulic oil discharged from the pump to the tank without supplying it to the actuator. However, for example, when another passage branches from the unload passage (41, 42) (not shown), the hydraulic oil may be supplied from the unload passage (41, 42) to the actuator. Two unload passages (41, 42) are provided, and such an embodiment is also called a dual bypass. The unload passages (41, 42) include a first unload passage 41 and a second unload passage 42.

  The first unload passage 41 and the second unload passage 42 are passages connected to different pumps when the direction switching valve 30 is applied to a hydraulic circuit. Hereinafter, the pump to which the first unload passage 41 is connected is referred to as a first pump (not shown). The pump to which the second unload passage 42 is connected is called a second pump (not shown).

  The first unload passage 41 is a passage connected to the first pump. The first unload passage 41 is a passage connected to the tank. The first unload passage 41 includes an upstream first unload passage 41a and a downstream first unload passage 41b. The upstream first unload passage 41 a is a passage on the upstream side (first pump side) of the first unload passage 41 with respect to the spool hole 33. The downstream first unload passage 41 b is a passage on the downstream side (tank side) of the first unload passage 41 with respect to the spool hole 33.

  The second unload passage 42 is a passage connected to a second pump different from the first pump to which the first unload passage 41 is connected. The second unload passage 42 is a passage connected to the tank. The second unload passage 42 includes an upstream second unload passage 42a and a downstream second unload passage 42b. The upstream second unload passage 42 a is a passage on the upstream side (second pump side) of the second unload passage 42 with respect to the spool hole 33. The downstream second unload passage 42 b is a passage on the downstream side (tank side) of the second unload passage 42 with respect to the spool hole 33.

  As will be described later, in this embodiment, the first tandem passage 301 communicated not only with the first supply passage 51 and the second supply passage 52 but also with each of the first unload passage 41 and the second unload passage 42. The second tandem passage 302 also functions as “a plurality of supply passages connectable to the bridge passage 53 and capable of supplying hydraulic oil to the bridge passage 53”. That is, the “plurality of supply passages” according to the present embodiment are passages having different connection modes with respect to the pump (working fluid supply source) and having different hydraulic oil supply functions (supply methods) from each other. Including. Specifically, the connection method to the pump (working fluid supply source) is a parallel type (first supply passage 51 and second supply passage 52 in this example) and a tandem type passage (first unload passage in this example). The first tandem passage 301 and the second tandem passage 302, which will be described later, are connected to the 41 and the second unload passage 42, respectively.

  In general, the hydraulic fluid can be circulated through the parallel passage on the downstream side regardless of whether the flow of the hydraulic fluid in the upstream parallel passage is blocked or not blocked with respect to the flow direction of the hydraulic oil. Therefore, by providing a throttle for reducing the cross-sectional area of the flow path in a specific parallel type passage (for example, the downstream side passage), priority is given to hydraulic oil in other parallel type passages (for example, the upstream side passage) where no restriction is provided. The flow rate of hydraulic oil flowing through the parallel-type passage can be adjusted. However, in the case where hydraulic oil is allowed to flow only through a parallel-type passage provided with a throttle, the pump pressure (hydraulic oil supply pressure) tends to increase more than necessary due to the influence of the throttle. On the other hand, when hydraulic oil is allowed to flow in the tandem type passage, the downstream tandem type passage is basically blocked and no hydraulic oil flows. For example, when actuators are provided on the upstream side and the downstream side, hydraulic oil is supplied to the upstream actuator through a parallel-type passage without a throttle, while the downstream actuator has a parallel-type passage with a throttle. It is also possible to configure the direction switching valve 30 so as to supply hydraulic oil through both the tandem passage and the tandem passage. In this case, by blocking the tandem path when hydraulic oil is supplied to the upstream actuator, the hydraulic actuator is supplied preferentially to the upstream actuator over the downstream actuator, and the upstream actuator and The hydraulic oil can be supplied to both of the downstream actuators via a parallel path. On the other hand, when the supply of hydraulic oil to the upstream actuator is shut off, the hydraulic oil is supplied only to the downstream actuator through the tandem path, while suppressing the increase in pump pressure by opening the tandem path. it can.

  The tank passage 45 is a passage connected to a tank (not shown). The tank passage 45 is a passage for returning the hydraulic oil discharged from the actuator and the hydraulic oil discharged through the unload passages (41, 42) to the tank.

  The supply passages (51, 52) are passages for supplying pump discharge oil to the actuator. The supply passages (51, 52) include a first supply passage 51 and a second supply passage 52 and can be connected to the bridge passage 53.

  The first supply passage 51 is a passage that can be connected to a pump. The first supply passage 51 may not be connected to the pump. The first supply passage 51 does not open directly to the spool hole 33. When the first supply passage 51 is connected to the pump, the first supply passage 51 is connected to the first pump to which the first unload passage 41 is connected. When connected to the first pump, the first supply passage 51 receives the hydraulic oil discharged from the first pump to supply the actuator. When the first supply passage 51 is connected to the first pump, the first supply passage 51 may be connected to the first unload passage 41 (upstream first unload passage 41a). In other words, the first supply passage 51 may be connected to the first pump via the first unload passage 41. In this case, the connection of the first supply passage 51 to the first unload passage 41 is performed outside the direction switching valve 30.

  The second supply passage 52 is a passage connectable to the pump. The second supply passage 52 may not be connected to the pump. The second supply passage 52 does not open directly into the spool hole 33. When the second supply passage 52 is connected to the pump, the second supply passage 52 is connected to the second pump to which the second unload passage 42 is connected. When the second supply passage 52 is connected to the second pump, the hydraulic fluid discharged from the second pump is received to supply the actuator to the actuator. When connected to the second pump, the second supply passage 52 may be connected to the second unload passage 42 (upstream second unload passage 42a). In other words, the second supply passage 52 may be connected to the second pump via the second unload passage 42. In this case, the connection of the second supply passage 52 to the second unload passage 42 is performed outside the direction switching valve 30.

  The bridge passage 53 is at least one of the first pump and the second pump when the passage (101, 102, 301, 302) is formed in at least one of the plurality of regions (201, 202, 401, 402). It is a passage for supplying hydraulic oil from either to the actuator. As shown in FIG. 3 and the like, the bridge passage 53 opens into the spool hole 33 and includes a first bridge passage 53a and a second bridge passage 53b. The first bridge passage 53 a is a passage for supplying hydraulic oil from at least one of the first pump and the second pump to the first actuator passage 61. The second bridge passage 53 b is a passage for supplying hydraulic oil from at least one of the first pump and the second pump to the second actuator passage 62.

  Both ends of the bypass passage 55 open into the spool hole 33, and the bridge passage 53 (especially the first bridge passage 53a in the illustrated example) and the actuator passage (particularly the first actuator passage 61 in the illustrated example) communicate with each other. Is the passage. That is, the stroke position in the spool hole 33 of the spool 80 is “a position where the first bridge passage 53a and the first actuator passage 61 are intended to communicate with each other (that is, the hydraulic oil is transferred from the first bridge passage 53a to the first actuator passage 61). ”In the position for supplying the first passage) and the first actuator passage 61 with the notch 81 of the spool 80 and the“ flow passage connecting the first bridge passage 53a and one opening of the bypass passage 55 ”. A “flow path connecting the other opening of the bypass passage 55” is formed in the spool hole 33. As a result, the hydraulic oil that has flowed out of the first bridge passage 53a into the spool hole 33 “routes through the bypass passage 55 and then into the first actuator passage 61 via the spool hole 33” and “first actuator It is sent to the first actuator passage 61 via a “route for directly flowing into the passage 61”.

  The “communication state of the first bridge passage 53a and the first actuator passage 61 via the spool hole 33 and the bypass passage 55” described above is “the first bridge passage 53a and the first actuator only via the spool hole 33”. It is preferable to be realized together with the “communication state with the passage 61”. However, the above-mentioned “communication state between the first bridge passage 53a and the first actuator passage 61 via the spool hole 33 and the bypass passage 55” and “the first bridge passage 53a and the first actuator passage 61 via only the spool hole 33”. If any one of “communication state” is realized, the other need not be realized. Further, the stroke position of the spool 80 in the spool hole 33 is “a position intended to prevent the first bridge passage 53a and the first actuator passage 61 from communicating with each other (that is, the hydraulic oil is transferred from the first bridge passage 53a to the first actuator passage 61). In the position for not supplying) at least one of both openings of the bypass passage 55 that opens to the spool hole 33 is closed by the land portion 83 of the spool 80.

  The actuator passages (61, 62) are the first pump and the second pump when the passages (101, 102, 301, 302) are formed in at least one of the plurality of regions (201, 202, 401, 402). It is a passage formed in the valve main body 31 for supplying hydraulic oil from at least one of them to the actuator via the bridge passage 53. The actuator passages (61, 62) open to the spool hole 33 while being connected to the actuator. The actuator passages (61, 62) include the first actuator passage 61 and the second actuator passage 62 described above.

  The first actuator passage 61 is a passage connected to the first port of the actuator. The second actuator passage 62 is a passage connected to the second port of the actuator.

  The region (201, 202, 401, 402) forms a passage (101, 102, 301, 302) for supplying hydraulic oil to at least one of the first pump and the second pump to the actuator. It is an area. The areas (201, 202, 401, 402) include a first parallel area 201, a second parallel area 202, a first tandem area 401, and a second tandem area 402.

  The first parallel region 201 is a region where the first parallel passage 101 that connects the first supply passage 51 to the bridge passage can be formed. The second parallel region 202 is a region where the second parallel passage 102 that connects the second supply passage 52 to the bridge passage 53 can be formed.

  The first tandem region 401 is a region where a first tandem passage 301 that connects the first unload passage 41 to the bridge passage 53 can be formed. The first tandem passage 301 may connect the first unload passage 41 and the bridge passage 53 inside the direction switching valve 30. The first tandem passage 301 may connect the first unload passage 41 and the bridge passage 53 outside the direction switching valve 30. In the illustrated example, when the first tandem passage 301 is formed, the first unload passage 41 and the bridge passage 53 are connected inside the direction switching valve 30. The second tandem region 402 is a region where a second tandem passage 302 that connects the second unload passage 42 to the bridge passage 53 can be formed. The second tandem passage 302 may connect the second unload passage 42 and the bridge passage 53 inside the direction switching valve 30. The second tandem passage 302 may connect the second unload passage 42 and the bridge passage 53 outside the direction switching valve 30. In the illustrated example, when the second tandem passage 302 is formed, the second unload passage 42 and the bridge passage 53 are connected inside the direction switching valve 30.

  When the first parallel passage 101 is formed in the first parallel region 201, the bridge passage 53 is connected to the first supply passage 51. When the second parallel passage 102 is formed in the second parallel region 202, the bridge passage 53 is connected to the second supply passage 52. When the first parallel passage 101 is formed in the first parallel region 201 and the second parallel passage 102 is formed in the second parallel region 202, the bridge passage 53 is connected to the first supply passage 51 and the second supply passage. 52.

  When the first parallel passage 101 is formed in the first parallel region 201 and the first supply passage 51 is connected to the first pump, the first supply passage is supplied to the bridge passage 53 from the first pump. The hydraulic oil flowing through 51 can flow. When the second parallel passage 102 is formed in the second parallel region 202 and the second supply passage 52 is connected to the second pump, the second supply passage is supplied to the bridge passage 53 from the second pump. The hydraulic oil flowing through 52 can flow. A first parallel passage 101 is formed in the first parallel region 201, a first supply passage 51 is connected to the first pump, a second parallel passage 102 is formed in the second parallel region 202, and a second supply passage 52 is formed. Is connected to the second pump, the bridge passage 53 is supplied with hydraulic oil from the first pump and flows through the first supply passage 51, and is supplied from the second pump and flows through the second supply passage 52. It becomes possible for the hydraulic oil that has joined the oil to flow.

  When the first tandem passage 301 is formed in the first tandem region 401, the bridge passage 53 is connected to the first unload passage 41. When the second tandem passage 302 is formed in the second tandem region 402, the bridge passage 53 is connected to the second unload passage 42. When the first tandem passage 301 is formed in the first tandem region 401 and the second tandem passage 302 is formed in the second tandem region 402, the bridge passage 53 is connected to the first unload passage 41 and the second unload passage 41. Connected to the load passage 42.

  When the first tandem passage 301 is formed in the first tandem region 401, the hydraulic oil flowing through the first unload passage 41 can flow through the bridge passage 53. When the second tandem passage 302 is formed in the second tandem region 402, the hydraulic oil flowing through the second unload passage 42 can flow through the bridge passage 53. When the first tandem passage 301 is formed in the first tandem region 401 and the second tandem passage 302 is formed in the second tandem region 402, the bridge passage 53 flows through the first unload passage 41. The hydraulic oil in which the hydraulic oil and the hydraulic oil flowing through the second unload passage 42 merge can flow.

  In the case where the first parallel passage 101 is formed in the first parallel region 201, the first supply passage 51 is connected to the first pump, and the first tandem passage 301 is formed in the first tandem region 401. In the bridge passage 53, it is possible to flow the hydraulic oil in which the hydraulic oil flowing through the first supply passage 51 and the hydraulic oil flowing through the first unload passage 41 merge.

  When the second parallel passage 102 is formed in the second parallel region 202, the second supply passage 52 is connected to the second pump, and the second tandem passage 302 is formed in the second tandem region 402, the bridge In the passage 53, the hydraulic oil in which the hydraulic oil flowing in the second supply passage 52 and the hydraulic oil flowing in the second unload passage 42 merge can flow.

  The first parallel passage 101 is formed in the first parallel region 201, the first supply passage 51 is connected to the first pump, the first tandem passage 301 is formed in the first tandem region 401, and the second parallel region When the second parallel passage 102 is formed in 202, the second supply passage 52 is connected to the second pump, and the second tandem passage 302 is formed in the second tandem region 402, the bridge passage 53 includes: A hydraulic oil in which the hydraulic oil flowing in the first supply passage 51 and the hydraulic oil flowing in the first unload passage 41 merge, and a hydraulic oil flowing in the second supply passage 52 and a hydraulic oil flowing in the second unload passage 42 It becomes possible for the hydraulic oil that has joined to flow. The inflow pattern of the hydraulic oil to the bridge passage 53 when one or more of the first parallel passage 101, the second parallel passage 102, the first tandem passage 301, and the second tandem passage 302 are formed is a pattern other than the above. Exists.

  As shown in FIG. 3 and the like, the regions (711 to 714) are regions for forming a plurality of passage holes (701 to 704) for providing regulating members such as check valves and blind plugs. That is, the plurality of passage holes (701 to 704) include a plurality of supply passages (a first supply passage 51, a second supply passage 52, a first tandem passage 301 connected to the first unload passage 41, and a second unload). A plurality of regulating members arranged between each of the second tandem passages 302) connected to the passage 42 and the bridge passage 53 are formed in the valve body 31. And in the direction switching valve 30 of this embodiment, these several passage holes (701-704) open in the same surface of the valve main body 31. FIG. The opening surfaces of the plurality of passage holes (701 to 704) in the valve body 31 are not particularly limited, but in the present embodiment, the plurality of passage holes (701 to 704) are actuator passages (the first actuator passage 61 and the second passage). The actuator passage 62) opens on the same surface as the surface on which it opens (in the example shown, the upper surface of the valve body 31 (see FIG. 2)). That is, the actuator passages (the first actuator passage 61 and the second actuator passage 62) of the present embodiment are opened on the same surface as the surface of the valve body 31 where the plurality of passage holes (701 to 704) are opened.

  Hereinafter, an example in which the check valve (71 to 74) is applied as a restriction member will be described. However, other restriction members such as a blind plug can be similarly installed. In the regions (711 to 714), a first restricting member region 711 capable of forming the first passing hole 701, a second restricting member region 712 capable of forming the second passing hole 702, and a third passing hole 703 can be formed. There is a fourth regulating member region 714 in which the third regulating member region 713 and the fourth passage hole 704 can be formed.

  The first restricting member region 711 is a second passage through which a check valve 71 disposed between the first parallel passage 101 and the bridge passage 53 can pass when the first parallel passage 101 is formed in the first parallel region 201. This is a region for forming one passing hole 701. The check valve 71 that prevents the backflow of hydraulic oil from the bridge passage 53 to the first parallel passage 101 is disposed at a predetermined installation location after being inserted into the first passage hole 701, and the first passage hole from the predetermined installation location. It is taken out of the direction switching valve 30 via 701. For example, when the first parallel passage 101 formed in the first parallel region 201 becomes unnecessary, a blind plug can be installed instead of the check valve 71. This blind plug is a member that blocks communication between the bridge passage 53 and the first parallel passage 101, is installed at a predetermined installation location after being inserted into the first passage hole 701, and from the predetermined installation location. It is taken out of the direction switching valve 30 through the first passage hole 701.

  The second regulating member region 712 is a second passage through which a check valve 72 disposed between the second parallel passage 102 and the bridge passage 53 can pass when the second parallel passage 102 is formed in the second parallel region 202. This is a region for forming the two passage holes 702. The check valve 72 for preventing the backflow of hydraulic oil from the bridge passage 53 to the second parallel passage 102 is disposed at a predetermined installation location after being inserted into the second passage hole 702, and from the predetermined installation location to the second passage hole. It is taken out of the direction switching valve 30 via 702. For example, when the second parallel passage 102 formed in the second parallel region 202 becomes unnecessary, a blind plug can be installed instead of the check valve 72. The blind plug is a member that blocks communication between the bridge passage 53 and the second parallel passage 102, and is installed at a predetermined installation location after being inserted into the second passage hole 702, and from the predetermined installation location. It is taken out of the direction switching valve 30 through the second passage hole 702.

  The third restricting member region 713 is configured such that when the first tandem passage 301 is formed in the first tandem region 401, the check valve 73 that is disposed between the first tandem passage 301 and the bridge passage 53 can pass therethrough. This is a region for forming the three passage holes 703. The check valve 73 for preventing the backflow of hydraulic oil from the bridge passage 53 to the first tandem passage 301 is disposed at a predetermined installation location after being inserted into the third passage hole 703, and from the predetermined installation location to the third passage hole. It is taken out of the direction switching valve 30 via 703. For example, when the first tandem passage 301 formed in the first tandem region 401 becomes unnecessary, a blind plug can be installed instead of the check valve 73. This blind plug is a member that blocks communication between the bridge passage 53 and the first tandem passage 301, and is installed at a predetermined installation location after being inserted into the third passage hole 703, and from the predetermined installation location. It is taken out of the direction switching valve 30 through the third passage hole 703.

  The fourth restricting member region 714 is a second passage through which a check valve 74 disposed between the second tandem passage 302 and the bridge passage 53 can pass when the second tandem passage 302 is formed in the second tandem region 402. This is a region for forming the four passage holes 704. The check valve 74 for preventing the backflow of hydraulic oil from the bridge passage 53 to the second tandem passage 302 is disposed at a predetermined installation location after being inserted into the fourth passage hole 704, and from the predetermined installation location to the fourth passage hole. It is taken out of the direction switching valve 30 via 704. For example, when the second tandem passage 302 formed in the second tandem region 402 becomes unnecessary, a blind plug can be installed instead of the check valve 74. The blind plug is a member that blocks communication between the bridge passage 53 and the second tandem passage 302, and is installed at a predetermined installation location after being inserted into the fourth passage hole 704, and from the predetermined installation location. It is taken out of the direction switching valve 30 through the fourth passage hole 704.

  In addition, the arrangement | positioning form of the above-mentioned area | region (711-714) and several through-hole (701-704) is not specifically limited. The above-mentioned region (711-714) and a plurality of passage holes (701-704) may be arranged, for example on the same straight line, and may not be arranged on the same straight line. Therefore, the plurality of check valves (71 to 74) and the plurality of passage holes (701 to 704) are viewed from the surface of the valve body 31 where the plurality of passage holes (701 to 704) are opened (shown in FIG. 2). In the example, when viewed from the upper surface of the valve main body 31, it may be arranged on the same straight line or may not be arranged on the same straight line. When the above-mentioned region (711-714), a plurality of passage holes (701-704), and a plurality of check valves (71-74) are arranged on the same straight line, there is a merit that manufacture is easy. On the other hand, when the above-mentioned region (711-714), a plurality of passage holes (701-704), and a plurality of check valves (71-74) are not arranged on the same straight line, these elements are arranged efficiently. Thus, there is an advantage that the direction switching valve 30 can be downsized (particularly downsized in the extending direction of the spool 80 and the spool hole 33).

  FIG. 7 is a conceptual diagram showing a state in which the bridge passage 53 and the like are viewed from the surface of the valve body 31 where a plurality of passage holes (701 to 704) are opened. FIG. 7 conceptually shows an example of the arrangement of the region (711 to 714), the plurality of passage holes (701 to 704), and the plurality of check valves (71 to 74), and is formed in the valve body 31. Only some of the elements are shown. In FIG. 7, for easy understanding, the bridge passage 53 is indicated by a solid line, and other elements (check valves (71 to 74), passage holes (701 to 704) and regions (711 to 714)) are indicated by dotted lines. It is shown.

  In the example shown in FIG. 7, the above-described region (711 to 714), the plurality of passage holes (701 to 704), and the plurality of check valves (71 to 74) are arranged in the extending direction of the bridge passage 53 (that is, the spool axis direction A). ) In a staggered manner. Specifically, the check valve 73 and the check valve 72 (the third passage hole 703 and the second passage hole) in a state where each element is viewed from the surface of the valve body 31 where the plurality of passage holes (701 to 704) are opened. 702; the third restricting member region 713 and the second restricting member region 712 are arranged on the same straight line, and check valve 71 and check valve 74 (first passing hole 701 and fourth passing hole 704; first restricting member region 711). And the fourth regulating member region 714) are arranged on the same straight line. However, “check valve 73 and check valve 72 (third passage hole 703 and second passage hole 702; third restriction member region 713 and second restriction member region 712)” and “check valve 71 and check valve 74 (first passage) The hole 701 and the fourth passage hole 704; the first restricting member region 711 and the fourth restricting member region 714) ”are not arranged on the same straight line.

  The arrangement form of the region (711 to 714), the plurality of passage holes (701 to 704), and the plurality of check valves (71 to 74) is not limited to the example shown in FIG. 7, and a plurality of supply passages (first supply passages) 51, the second supply passage 52, the first tandem passage 301 connected to the first unload passage 41, and the second tandem passage 302 connected to the second unload passage 42) and the bridge passage 53. Any arrangement may be employed as long as the flow of the hydraulic oil can be appropriately controlled. For example, regarding the arrangement order in the extending direction of the bridge passage 53 (that is, the spool axis direction A), in the example shown in FIG. These check valves (71 to 74) may be arranged in any order. Further, the region (711 to 714) and the plurality of passage holes (701 to 704) may be arranged in any order with respect to the extending direction of the bridge passage 53. Further, in the example shown in FIG. 7, two check valves (check valve 71 and check valve 74) are connected to the other two check valves (check valve) in the direction perpendicular to the extending direction of the bridge passage 53 (that is, the spool axis direction A). Although the valve 73 and the check valve 72) are arranged at different positions, any one or three check valves may be arranged at different positions from the other check valves. Further, the region (711 to 714) and the plurality of passage holes (701 to 704) may also be arranged at any one or three different positions with respect to the direction perpendicular to the extending direction of the bridge passage 53. Good. Further, in the example shown in FIG. 7, two check valves (check valve 71 and check valve 74) are connected to the other two check valves (check valve) in the direction perpendicular to the extending direction of the bridge passage 53 (that is, the spool axis direction A). Although arranged in the same direction with respect to the valve 73 and the check valve 72), they may be arranged in different directions. Also, the region (711 to 714) and the plurality of passage holes (701 to 704) are arranged in the same direction with respect to the other two in the direction perpendicular to the extending direction of the bridge passage 53. Alternatively, they may be arranged in different directions.

  On the other hand, the spool 80 is inserted into the spool hole 33 as shown in FIG. The spool 80 has a substantially cylindrical shape. The axial direction of the spool 80 (the direction of the central axis of the substantially cylinder) is defined as the spool axial direction A. One side in the spool axial direction A is one side A1, and the other side is the other side A2. The spool 80 can slide (stroke) in the spool axial direction A with respect to the spool hole 33.

  The spool 80 switches connection and disconnection between the passages (for example, the bridge passage 53 and the actuator passage (61, 62)). This spool 80 switches the presence / absence of connection between passages and the opening degree (valve opening degree) of the connection. More specifically, the spool 80 brings the passages into any one of a “blocking state (fully closed state)” and a “connected state (including“ fully opened state ”and“ throttle state ”). The “blocking state” is a state where the passages are not connected (blocked state). The “connected state” is a state where the passages are connected (connected state). The “connection state” includes a “fully open state” and an “aperture state”. The “fully open state” is a state in which the opening degree of the flow path between the passages is the maximum (the opening degree changes variously when the spool 80 is stroked from the end of the one side A1 to the end of the other side A2). The degree is the maximum). For example, the “fully open state” is a state where the flow paths between the passages are not restricted. The “squeezed state” is a state in which the flow paths between the passages are narrower than the “fully open state” (excluding the blocked state).

  The spool 80 has a different configuration depending on the pattern of passages (101, 102, 301, 302) formed in a plurality of regions (201, 202, 401, 402). Specifically, when the passages (101, 102, 301, 302) are formed in the bridge passage 53 so that the hydraulic oil from both the first pump and the second pump flows, the first pump is provided in the bridge passage 53. When the passage (101, 102, 301, 302) is formed so that the hydraulic oil from only the second oil flows, and the passage (101, 102, 301, 302) so that the hydraulic oil from only the second pump flows through the bridge passage 53. 302) is formed, a spool having a different configuration is used.

<In the case where the hydraulic oil flows from both the first pump and the second pump through the bridge passage>
In this case, the spool 80 employs the following configuration.
The spool 80 switches connection and disconnection between the bridge passage 53 and the actuator passages (61, 62).
The spool 80 switches connection and disconnection between the actuator passages (61, 62) and the tank passage 45.
The spool 80 switches connection and disconnection between the upstream first unload passage 41a and the downstream first unload passage 41b.
The spool 80 switches connection and disconnection between the upstream side second unload passage 42a and the downstream side second unload passage 42b.

  The spool 80 includes a plurality of notches 81 and a plurality of lands 83. The notches 81 and the lands 83 are alternately arranged (formed) in the spool axial direction A.

  The notch 81 connects the passages (between the passages). The notch 81 connects openings of the passage to the spool hole 33. Hereinafter, the opening to the spool hole 33 is referred to as “opening”. In the illustrated example, the passages (41, 42, 45, 53, 55, 61, 62) of the plurality of passages (41 to 62) open to the spool hole 33. The notch 81 connects the passages via the spool hole 33. As shown in FIG. 3 and the like, the notch 81 is a portion that is recessed inward in the radial direction of the spool 80 with respect to the land 83. A plurality of the notches 81 are provided, for example, four may be provided, two, three, or five or more may be provided. The notch 81 includes, for example, a first unload passage notch and a second unload passage notch. The first unload passage notch connects the upstream first unload passage 41a and the downstream first unload passage 41b. The notch for the second unload passage connects the upstream second unload passage 42a and the downstream second unload passage 42b.

  The land portion 83 is in a state where the passages are not connected (blocked state). The land portion 83 prevents the passages from being connected to each other by the notch portion 81. The land portion 83 is in contact with a wall portion (the inner surface of the spool hole 33) that forms the spool hole 33. The land portion 83 closes the opening of the passage (41, 42, 45, 53, 55, 61, 62). Alternatively, the land portion 83 closes the spool hole 33 between the passages. The land part 83 makes the passages in a throttled state. The land part 83 makes the opening of the passage (41, 42, 45, 53, 55, 61, 62) narrower than the fully opened state. A plurality of land portions 83 may be provided, for example, 5 locations may be provided, 4 locations or less, or 6 locations or more may be provided. The land portion 83 includes, for example, an unload passage land portion.

  The unload path land portion can block the unload path (41, 42) (can be in a blocked state). The unload passage land portion includes a first unload passage land portion, a second unload passage land portion, and a third unload passage land portion.

  The first unload passage land portion shuts off or restricts the first unload passage 41 when the direction switching valve 30 moves from the neutral position 30a shown in FIG. 1 to the first operation position 30b (not shown). To. When the second unload passage land portion moves from the neutral position 30a shown in FIG. 1 to the second operation position 30c, the second unload passage 42 is set in a shut-off state or a throttled state (not shown).

  The third unload passage land portion can block the first unload passage 41 and can block the second unload passage 42. In this configuration, since the land portion for the third unload passage is used for two purposes, the land portion can be shared. The third unload passage land portion puts the second unload passage 42 in a cut-off state or a throttled state (not shown) at the first operating position 30b. The third unload passage land portion places the first unload passage 41 in a shut-off state or a throttled state (not shown) at the second operating position 30c. The above is the configuration of the spool 80 in the configuration in which hydraulic oil from both the first pump and the second pump flows through the bridge passage 53. In the case where the hydraulic fluid from either the first pump or the second pump flows through the bridge passage 53, the spool 80 employs the following configuration.

<In the case of a configuration in which hydraulic oil flows only from the first pump through the bridge passage>
In this case, the spool 80 employs the following configuration.
The spool 80 switches connection and disconnection between the bridge passage 53 and the actuator passages (61, 62).
The spool 80 switches connection and disconnection between the actuator passages (61, 62) and the tank passage 45.
The spool 80 switches connection and disconnection between the upstream first unload passage 41a and the downstream first unload passage 41b.
The spool 80 always connects the upstream second unload passage 42a and the downstream second unload passage 42b.

  In this case, the unload passage land portion functions as follows.

  When the land portion for the first unload passage moves from the neutral position 30a to the first operation position 30b, the first unload passage 41 is brought into a blocking state or a throttled state (not shown). The second unload passage land portion does not have a function of bringing the second unload passage 42 into the cut-off state or the throttle state when the neutral position 30a is shifted to the second operation position 30c. Is kept fully open.

  The land portion for the third unload passage does not have a function of bringing the second unload passage 42 into the cut-off state or the throttle state when the first operating position 30b is reached, and the second unload passage 42 is maintained in the fully open state. The The third unload passage land portion places the first unload passage 41 in a shut-off state or a throttled state (not shown) at the second operating position 30c.

  Other configurations are the same as the configuration in which hydraulic oil from both the first pump and the second pump flows through the bridge passage 53.

<In the case where the hydraulic oil flows only from the second pump through the bridge passage>
In this case, the spool 80 employs the following configuration.
The spool 80 switches connection and disconnection between the bridge passage 53 and the actuator passages (61, 62).
The spool 80 switches connection and disconnection between the actuator passages (61, 62) and the tank passage 45.
The spool 80 always connects the upstream first unload passage 41a and the downstream first unload passage 41b.
The spool 80 switches connection and disconnection between the upstream side second unload passage 42a and the downstream side second unload passage 42b.

  In this case, the unload passage land portion functions as follows.

  The land portion for the first unload passage does not have a function of bringing the first unload passage 41 into the shut-off state or the throttle state when the neutral position 30a is shifted to the first operation position 30b. Is kept fully open. When the second unload passage land portion moves from the neutral position 30a to the second operation position 30c, the second unload passage 42 is brought into a cutoff state or a throttled state (not shown).

  The third unload passage land portion puts the second unload passage 42 in a cut-off state or a throttled state (not shown) at the first operating position 30b. The land portion for the third unload passage does not have a function of bringing the first unload passage 41 into the cut-off state or the throttled state at the second operation position 30c, and the first unload passage 41 is maintained in the fully open state. The

  Other configurations are the same as the configuration in which hydraulic oil from both the first pump and the second pump flows through the bridge passage 53.

(Arrangement of passages (41-62))
Of the plurality of passages (41 to 62), the passages (41, 42, 45, 53, 55, 61, 62) that open to the spool hole 33 have openings (openings to the spool hole 33) in the spool axial direction A. From one side A1 to the other side A2, for example, “one of the two openings of the tank passage 45, the first actuator passage 61, and the bypass passage 55 on the one side A1 (the other opening), the first bridge One of the two openings of the passage 53a (one side A1 bridge passage 53), the bypass passage 55 (one opening), the unload passage (41, 42), the second bridge passage 53b (the other side A2) ), The second actuator passage 62, and the tank passage 45 "on the other side A2. The opening of the tank passage 45 on the one side A1 and the opening of the tank passage 45 on the other side A2 communicate with each other inside the valve main body 31 (not necessarily inside the valve main body 31).

(Arrangement of unload passages (41, 42))
The unload passages (41, 42) are arranged as follows. The unload passages (41, 42) are arranged so as to suppress the size of the spool hole 33 (the size of the spool 80) in the spool axial direction A from being excessively increased. Specifically, it is as follows.

(Arrangement order of unload passages (41, 42))
The unload passages (41, 42) are connected to the first unload passage 41 and the second unload passage 42 when they need to be switched between connection and disconnection. Thus, the third unload passage land portion is arranged so that it can be shared (above). Specifically, the first unload passage 41 and the second unload passage 42 are arranged so as to be adjacent (adjacent to the spool axis direction A, the same applies hereinafter) (refer to the following for “adjacent”). . For example, the downstream first unload passage 41b and the upstream second unload passage 42a are arranged adjacent to each other. For example, the upstream first unload passage 41a and the downstream first unload passage 41b are arranged adjacent to each other. For example, the upstream second unload passage 42a and the downstream second unload passage 42b are arranged adjacent to each other.

Here, the passage α and the passage β are “adjacent” means that they are arranged as in the following [Arrangement Example 1] or [Arrangement Example 2].
[Arrangement Example 1] No other passage (passage other than the passage α and the passage β) is disposed between the passage α and the passage β. In the spool hole 33, the opening of the other passage is not disposed between the opening of the passage α (opening to the spool hole 33) and the opening of the passage β.
[Arrangement Example 2] The passage α and the passage β are sequentially arranged in the spool axial direction A. More specifically, the passage β is arranged next to the passage α in the order from the one side A1 to the other side A2 in the spool axial direction A (or the passage α is arranged next to the passage β). In the spool hole 33, the opening of the passage α and the opening of the passage β are sequentially arranged in the spool axial direction A.

  The first unload passage 41 and the second unload passage 42 extend in a direction perpendicular to the spool axial direction A across one side surface of the valve body 31 and the other side surface facing the side surface. Specifically, in the first unload passage 41, the upstream first unload passage 41 a extends from the opening side to the spool hole 33 in a direction perpendicular to the spool axial direction A, and the valve on the one side surface of the valve main body 31. Open to the outside of the main body 31. The downstream first unload passage 41b extends from the opening side to the spool hole 33 to the side opposite to the side on which the upstream first unload passage 41a extends in the direction orthogonal to the spool axial direction A. In the other side surface, the valve body 31 opens to the outside. In the second unload passage 42, the upstream second unload passage 42 a extends from the opening side to the spool hole 33 in a direction perpendicular to the spool axial direction A, and on the one side surface of the valve body 31, Open to the outside. The downstream second unload passage 42b extends from the opening side to the spool hole 33 to the side opposite to the side on which the upstream second unload passage 42a extends in the direction orthogonal to the spool axial direction A. In the other side surface, the valve body 31 opens to the outside.

(Arrangement of supply passages (51, 52))
The supply passages (51, 52) extend along the unload passages (41, 42). The supply passages (51, 52) are arranged on the radially outer side than the unload passages (41, 42). The first supply passage 51 extends from the one side surface of the valve body 31 where the first unload passage 41 (upstream side first unload passage 41a) opens toward the other side surface. The first supply passage 51 reaches an intermediate position between the one side surface and the other side surface of the valve body 31. The second supply passage 52 extends from the one side surface of the valve main body 31 where the second unload passage 42 (upstream second unload passage 42a) opens toward the other side surface. The second supply passage 52 reaches an intermediate position between the one side surface and the other side surface of the valve body 31. The first unload passage 41 and the first supply passage 51 are arranged at positions where at least a part of each other overlaps in the radial direction. The second unload passage 42 and the second supply passage 52 are arranged at positions where at least a part of each other overlaps in the radial direction.

(Arrangement of bridge passageway (53))
In a cross-sectional view orthogonal to the direction in which the unload passages (41, 42) and the supply passages (51, 52) extend, the first bridge passage 53 a is radially outward from the opening side to the spool hole 33 with respect to the spool axial direction A. And then extend toward the second bridge passage 53b along the spool axial direction A. The first bridge passage 53 a reaches the radially outer side of the first supply passage 51. The second bridge passage 53b extends outward in the radial direction with respect to the spool axial direction A from the opening side to the spool hole 33, and then extends along the spool axial direction A toward the first bridge passage 53a. The second bridge passage 53 b reaches the outer side in the radial direction of the second supply passage 52. The first bridge passage 53 a and the second bridge passage 53 b are connected to each other at positions radially outside the first supply passage 51 and the second supply passage 52.

  4 and the like, the bridge passage 53 is formed in an inverted U shape. The bridge passage 53 covers the unload passage (41, 42) and the supply passage (51, 52) from both sides in the spool axial direction A and from the outside in the radial direction. Of the first bridge passage 53a, the portion on the connection portion side with the second bridge passage 53b and the first supply passage 51 overlap in the radial direction. Of the second bridge passage 53b, the portion on the connection portion side with the first bridge passage 53a and the second supply passage 52 overlap in the radial direction. On the other hand, when viewed from the side, the intermediate portion of the first bridge passage 53a (the intermediate position between the opening side to the spool hole 33 and the connecting portion side of the second bridge passage 53b) and the first unload passage 41 (the first upstream side). The unload passage 41a) is close in the spool axial direction and radial direction. An intermediate portion of the second bridge passage 53b (an intermediate position between the opening side to the spool hole 33 and the connecting portion side of the first bridge passage 53a), a second unload passage 42 (upstream second unload passage 42a), Are close in the spool axial direction and radial direction.

(Location (201, 202, 401, 402) position)
The first parallel region 201 is set at a position where a part thereof faces the first supply passage 51 and another part faces the bridge passage 53. Specifically, the first parallel region 201 is set between the first supply passage 51 and a portion of the first bridge passage 53a on the connection portion side with the second bridge passage 53b. That is, the portion of the first bridge passage 53a on the connection portion side with the second bridge passage 53b, the first parallel region 201, and the first supply passage 51 overlap in the radial direction. Therefore, the first parallel passage 101 can be formed by forming a hole in the first parallel region 201 along the radial direction from the first bridge passage 53 a toward the first supply passage 51. A part of the second parallel region 202 faces the second supply passage 52 and the other part thereof is set at a position facing the bridge passage 53. Specifically, the second parallel region 202 is set between the second supply passage 52 and a portion of the second bridge passage 53b that is connected to the first bridge passage 53a. That is, the portion of the second bridge passage 53b on the connection portion side with the first bridge passage 53a, the second parallel region 202, and the second supply passage 52 overlap in the radial direction. Therefore, the second parallel passage 102 can be formed by forming a hole in the second parallel region 202 along the radial direction from the second bridge passage 53 b toward the second supply passage 52.

  A part of the first tandem region 401 is set at a position facing the outside of the first unload passage 41 and the valve body 31 and the other part facing the bridge passage 53. Specifically, the first tandem region 401 is set between the intermediate portion of the first bridge passage 53a and the first unload passage 41 (upstream first unload passage 41a). Therefore, in the first tandem region 401, a hole is formed between one side surface of the valve body 31 and the intermediate portion of the first bridge passage 53a and the first unload passage 41 (upstream first unload passage 41a). Thus, the first tandem passage 301 can be formed. When the first tandem passage 301 is connected to the first unload passage 41 outside the valve body 31, a part of the first tandem region 401 faces the first unload passage 41. It does not have to be.

  A part of the second tandem region 402 faces the second unload passage 42 and the other part is set at a position facing the outside of the valve body 31. Specifically, the second tandem region 402 is set between an intermediate portion of the second bridge passage 53b and the second unload passage 42 (downstream second unload passage 42b). Therefore, in the second tandem region 402, a hole is formed between the intermediate portion of the second bridge passage 53b and the second unload passage 42 (downstream second unload passage 42b) from one side surface of the valve body 31. By doing so, the second tandem passage 302 can be formed compactly. When the second tandem passage 302 is connected to the second unload passage 42 inside the valve body 31, a part of the second tandem region 402 faces the second unload passage 42. Set to

(Position of region (711-714))
When the first parallel passage 101 is formed in the first parallel region 201, the first restricting member region 711 includes a part of the first restricting member region 711 including the first parallel passage 101 and the bridge passage 53. The other part is set to a position facing the outside of the direction switching valve 30. Accordingly, the first passage hole 701 can be formed as a hole communicating with the inside of the bridge passage 53, the inside of the first parallel passage 101, and the outside of the direction switching valve 30. Thereby, the check valve 71 (regulating member) can be provided between the first parallel passage 101 and the bridge passage 53 through the first passage hole 701 from the outside of the direction switching valve 30. Specifically, the first restricting member region 711 includes a portion of the first bridge passage 53a on the connection portion side with the second bridge passage 53b, the first parallel region 201, and the first supply passage 51. , Is set to a position overlapping in the radial direction.

  When the second parallel passage 102 is formed in the second parallel region 202, the second restricting member region 712 includes a part of the second restricting member region 712, the second parallel passage 102 and the bridge passage 53. The other part is set to a position facing the outside of the direction switching valve 30. Thereby, the second passage hole 702 can be formed as a hole communicating with the inside of the bridge passage 53, the inside of the second parallel passage 102, and the outside of the direction switching valve 30. Thereby, the check valve 72 (regulating member) can be provided between the second parallel passage 102 and the bridge passage 53 through the second passage hole 702 from the outside of the direction switching valve 30. Specifically, the second restricting member region 712 includes a portion of the second bridge passage 53b that is connected to the first bridge passage 53a, the second parallel region 202, and the second supply passage 52. , Is set to a position overlapping in the radial direction.

  When the first tandem passage 301 is formed in the first tandem region 401, the third restricting member region 713 includes a part of the third restricting member region 713 that includes the first tandem passage 301 and the bridge passage 53. The other part is set to a position facing the outside of the direction switching valve 30. Thereby, the third passage hole 703 can be formed as a hole communicating with the inside of the bridge passage 53, the inside of the first tandem passage 301, and the outside of the direction switching valve 30. Thereby, the check valve 73 (regulating member) can be provided between the first tandem passage 301 and the bridge passage 53 through the third passage hole 703 from the outside of the direction switching valve 30. Specifically, the third restricting member region 713 is set at a position that overlaps the intermediate portion of the first bridge passage 53a, the first tandem region 401, and the first unload passage 41 in the radial direction. .

  When the second tandem passage 302 is formed in the second tandem region 402, a part of the fourth restricting member region 714 includes the second tandem passage 302, the bridge passage 53, and the fourth restriction member region 714. The other part is set to a position facing the outside of the direction switching valve 30. Thereby, the fourth passage hole 704 can be formed as a hole communicating with the inside of the bridge passage 53, the inside of the second tandem passage 302, and the outside of the direction switching valve 30. Thereby, the check valve 74 (regulating member) can be provided between the second tandem passage 302 and the bridge passage 53 through the fourth passage hole 704 from the outside of the direction switching valve 30. Specifically, the fourth restriction member region 714 is set at a position that overlaps the intermediate portion of the second bridge passage 53b, the second tandem region 402, and the second unload passage 42 in the radial direction. .

(Operation)
The direction switching valve 30 can be operated in response to an operation of the direction switching valve 30 (an operation by a construction machine operator, for example, a lever operation). In response to this operation, the direction switching valve 30 switches between the neutral position 30a, the first operating position 30b, and the second operating position 30c. In response to this operation, the spool 80 changes the stroke position. As a result, the spool 80 switches the presence / absence of connection between the passages and the opening degree of the connection (valve opening degree). Then, when the passage (101, 102, 301, 302) is formed in at least one of the plurality of regions (201, 202, 401, 402), from at least one of the first pump and the second pump It is possible to adjust whether the hydraulic oil is supplied to or discharged from the actuator (supply and discharge) and the flow rate of the hydraulic oil supplied to and discharged from the actuator.

  The spool 80 performs different operations depending on the pattern of the passages (101, 102, 301, 302) formed in the plurality of regions (201, 202, 401, 402). Specifically, when the passages (101, 102, 301, 302) are formed in the bridge passage 53 so that the hydraulic oil from both the first pump and the second pump flows, the first pump is provided in the bridge passage 53. When the passage (101, 102, 301, 302) is formed so that the hydraulic oil from only the second oil flows, and the passage (101, 102, 301, 302) so that the hydraulic oil from only the second pump flows through the bridge passage 53. Different operations are performed when 302) is formed. When different operations are performed for each pattern, the spool 80 corresponding to each pattern is used.

<In the case where the hydraulic oil flows from both the first pump and the second pump through the bridge passage>
When the passage (101, 102, 301, 302) is formed in the region (201, 202, 401, 402) so that the hydraulic oil from both the first pump and the second pump flows into the bridge passage 53. The direction switching valve 30 operates as follows.

(Neutral position 30a)
When the switching position of the direction switching valve 30 is the neutral position 30a, the direction switching valve 30 operates as follows.
[Operation 1a] The direction switching valve 30 fully opens the first unload passage 41. Specifically, the upstream first unload passage 41a and the downstream first unload passage 41b are fully opened through the first unload passage notch.
[Operation 1b] The direction switching valve 30 fully opens the second unload passage 42. Specifically, the direction switching valve 30 fully opens the upstream second unload passage 42a and the downstream second unload passage 42b via the second unload passage notch.
[Operation 1c] The direction switching valve 30 puts the bridge passage 53 (the first bridge passage 53a and the second bridge passage 53b) into a closed state.
[Operation 1d] The direction switching valve 30 puts the actuator passages (61, 62) in a closed state.
[Operation 1e] The direction switching valve 30 brings the tank passage 45 into a shut-off state.
[Operation 1f] As a result, when the unload passage (41, 42) is connected to the tank, the hydraulic oil discharged from the first pump and the second pump passes through the unload passage (41, 42), It will be returned to the tank. When the actuator passages (61, 62) are connected to the actuator, the hydraulic oil discharged from the first pump and the second pump is not supplied from the direction switching valve 30 to the actuator.

(First operation position 30b)
When the switching position is the first operating position 30b, the direction switching valve 30 is in a state where hydraulic oil is supplied to and discharged from the actuator passages (61, 62). When the switching position of the direction switching valve 30 is the first operating position 30b, the direction switching valve 30 operates as follows.
[Operation 2a] The direction switching valve 30 brings the first unload passage 41 into a shut-off state or a throttled state (not shown). Specifically, the direction switching valve 30 brings the upstream first unload passage 41a and the downstream first unload passage 41b into a cut-off state or a throttle state by the first unload passage land portion.
[Operation 2b] The direction switching valve 30 brings the second unload passage 42 into a shut-off state or a throttled state (not shown). Specifically, the direction switching valve 30 places the upstream side second unload passage 42a and the downstream side second unload passage 42b in a cutoff state or a throttle state by the third unload passage land portion.
[Operation 2c] The direction switching valve 30 brings the first bridge passage 53a (bridge passage 53) and the first actuator passage 61 into a connected state.
[Operation 2d] The direction switching valve 30 puts the second bridge passage 53b in a closed state.
[Operation 2e] The direction switching valve 30 brings the second actuator passage 62 and the tank passage 45 into a connected state.
[Operation 2f] As a result, the hydraulic oil discharged from the first pump and the second pump flows into the bridge passage 53.
[Operation 2g] The hydraulic oil flowing through the bridge passage 53 flows through the first actuator passage 61. When the first actuator passage 61 is connected to the actuator, the hydraulic oil flowing through the first actuator passage 61 is supplied to the actuator. The hydraulic oil discharged from the actuator flows through the tank passage 45 via the second actuator passage 62. The hydraulic oil flowing through the tank passage 45 returns to the tank.

(Second operating position 30c)
When the switching position is the second operating position 30c, the direction switching valve 30 is in a state in which hydraulic oil is supplied to and discharged from the actuator passages (61, 62). When the switching position of the direction switching valve 30 is the second operating position 30c, the direction switching valve 30 operates as follows.
[Operation 3a] The direction switching valve 30 brings the first unload passage 41 into a shut-off state or a throttle state. Specifically, the direction switching valve 30 causes the upstream first unload passage 41a and the downstream first unload passage 41b to be cut off or throttled by the third unload passage land portion.
[Operation 3b] The direction switching valve 30 brings the second unload passage 42 into a shut-off state or a throttled state (not shown). Specifically, the direction switching valve 30 causes the upstream side second unload passage 42a and the downstream side second unload passage 42b to be cut off or throttled by the second unload passage land portion.
[Operation 3c] The direction switching valve 30 brings the second bridge passage 53b (bridge passage 53) and the second actuator passage 62 into a connected state.
[Operation 3d] The direction switching valve 30 puts the first bridge passage 53a into a closed state.
[Operation 3e] The direction switching valve 30 brings the first actuator passage 61 and the tank passage 45 into a connected state.
[Operation 3f] As a result, the hydraulic oil discharged from the first pump and the second pump flows into the bridge passage 53.
[Operation 3g] The hydraulic oil flowing through the bridge passage 53 flows through the second actuator passage 62. When the second actuator passage 62 is connected to the actuator, the hydraulic oil flowing through the second actuator passage 62 is supplied to the actuator. The hydraulic oil discharged from the actuator flows through the tank passage 45 via the first actuator passage 61. The hydraulic oil flowing through the tank passage 45 returns to the tank.

<In the case of a configuration in which hydraulic oil flows only from the first pump through the bridge passage>
When the passage (101, 102, 301, 302) is formed in the region (201, 202, 401, 402) so that only the hydraulic oil from the first pump flows into the bridge passage 53, the direction switching valve 30 operates as follows at the first operating position 30b.
[Operation 2a-1] The direction switching valve 30 brings the first unload passage 41 into a shut-off state or a throttled state (not shown).
[Operation 2b-1] The direction switching valve 30 fully opens the second unload passage 42.
[Operation 2f-1] The hydraulic oil discharged from the first pump flows into the bridge passage 53.
The direction switching valve 30 operates as follows at the second operating position 30c.
[Operation 3a-1] The direction switching valve 30 brings the first unload passage 41 into a shut-off state or a throttled state (not shown).
[Operation 3b-1] The direction switching valve 30 fully opens the second unload passage 42.
[Operation 3 f-1] The hydraulic oil discharged from the first pump flows into the bridge passage 53.

  Other configurations are the same as the configuration in which hydraulic oil from both the first pump and the second pump flows through the bridge passage 53.

<In the case where the hydraulic oil flows only from the second pump through the bridge passage>
When the passage (101, 102, 301, 302) is formed in the region (201, 202, 401, 402) so that only the hydraulic oil from the second pump flows into the bridge passage 53, the direction switching valve 30 operates as follows at the first operating position 30b.
[Operation 2a-2] The direction switching valve 30 causes the first unload passage 41 to be fully opened.
[Operation 2b-2] The direction switching valve 30 brings the second unload passage 42 into a shut-off state or a throttled state (not shown).
[Operation 2f-2] The hydraulic oil discharged from the second pump flows into the bridge passage 53.
The direction switching valve 30 operates as follows at the second operating position 30c.
[Operation 3a-2] The direction switching valve 30 causes the first unload passage 41 to be fully opened.
[Operation 3b-2] The direction switching valve 30 brings the second unload passage 42 into a closed state or a throttled state (not shown).
[Operation 3f-2] The hydraulic oil discharged from the second pump flows into the bridge passage 53.

  Other configurations are the same as the configuration in which hydraulic oil from both the first pump and the second pump flows through the bridge passage 53.

  According to the above configuration, the passage (101, 102, 301, 302) is selected from the first parallel area 201, the second parallel area 202, the first tandem area 401, and the second tandem area 402. One or more can be formed. Thereby, a plurality of types of patterns that connect the pumps (first pump, second pump) and the bridge passage 53 can be formed. The spool 80 switches connection and disconnection between the bridge passage 53 and the actuator passage (61, 62) depending on the position. As a result, the hydraulic oil can be supplied from the pump to the bridge passage 53 in a plurality of types of passage patterns corresponding to the selectively formed passages (101, 102, 301, 302). Therefore, according to the direction switching valve 30, the passages (101, 102, 301, 301) are selected from the first parallel region 201, the second parallel region 202, the first tandem region 401, and the second tandem region 402. By selectively forming one or more of 302), a plurality of types of passage patterns for supplying hydraulic oil from the pump to the actuator can be selectively formed.

  In addition, when the first parallel passage 101 is formed in the first parallel region 201, the check valve 71 is provided to prevent the backflow of hydraulic oil from the bridge passage 53 to the first parallel passage 101. In this case, the hydraulic oil can be properly passed. For example, when the first parallel passage 101 formed in the first parallel region 201 becomes unnecessary, a blind plug that blocks communication between the bridge passage 53 and the first parallel passage 101 can be provided as a regulating member. . In this case, the passage pattern for supplying hydraulic oil from the pump to the actuator in the direction switching valve 30 can be switched to a different passage pattern. The second restricting member region 712, the third restricting member region 713, and the fourth restricting member region 714 are also the same as the first restricting member region 711.

  An example in which plural types of passage patterns for supplying hydraulic oil from the pump to the actuator in the direction switching valve 30 are selectively formed will be described below.

  FIG. 8 is a circuit diagram of a construction machine hydraulic circuit 1 (hereinafter, referred to as a hydraulic circuit 1) to which a plurality of the above-described directional control valves 30 (30A, 30B) having a passage pattern are applied. The hydraulic circuit 1 is a hydraulic circuit used for construction machines (not shown). The construction machine is a machine (hydraulic system) for performing construction work. The construction machine is, for example, a hydraulic excavator. The hydraulic circuit 1 includes a pump (11, 12) serving as a working fluid supply source, a tank 15, an actuator 20 (20A, 20B), and a direction switching valve 30 (30A, 30B) in which a passage pattern is formed. Prepare.

  The pumps (11, 12) are hydraulic pumps that discharge oil (pressure oil, hydraulic oil), and a plurality of supply passages (first supply passage 51, second supply passage 52) of the direction switching valve 30 (30A, 30B). The first tandem passage 301 connected to the first unload passage 41 and the second tandem passage 302 connected to the second unload passage 42 are communicated. The pumps (11, 12) are variable capacity type. In the pumps (11, 12), for example, the capacity is changed by changing the tilt angle of the swash plate, and when the capacity is changed, the discharge amount (the discharge amount of hydraulic oil per one rotation of the input shaft) is changed. The pumps (11, 12) are composed of two pumps. The pump (11, 12) includes a first pump 11 and a second pump 12. The pumps (11, 12) are, for example, split pumps. The split pump is a pump in which a plurality of pumps (first pump 11 and second pump 12) are driven by one input shaft. In the split pump, the first pump 11 and the second pump 12 are integrally configured. In the split pump, the discharge amount of the first pump 11 and the discharge amount of the second pump 12 are equal. The pumps (11, 12) may not be split pumps. The first pump 11 and the second pump 12 may be separate. The input shaft of the first pump 11 and the input shaft of the second pump 12 may or may not be common. The discharge amount of the first pump 11 and the discharge amount of the second pump 12 may be the same or different.

  The tank 15 stores hydraulic oil. The tank 15 supplies hydraulic oil to the pumps (11, 12). The hydraulic oil discharged from the pumps (11, 12) and returned through the actuator 20 is returned to the tank 15. The hydraulic oil discharged from the pumps (11, 12) and not passing through the actuator 20 is returned to the tank 15.

  The actuator 20 operates the construction machine. The actuator 20 communicates with the actuator passages (61, 62) of the direction switching valve 30 (30A, 30B), and is a hydraulic actuator that is driven when hydraulic oil is supplied from the pumps (11, 12). The actuator 20 is driven by supplying hydraulic oil from at least one of the first pump 11 and the second pump 12. When the construction machine is a hydraulic excavator, the application of the actuator 20 includes traveling, turning, bucket rotating, arm hoisting, and boom hoisting.

  As an example, the actuator 20A in FIG. 8 is a hydraulic cylinder (arm cylinder) for raising and lowering (raising and lowering, rotating) the arm with respect to the boom. As an example, the actuator 20B is a hydraulic motor (turning motor) for turning the upper turning body with respect to the lower traveling body. Each of the actuator 20 </ b> A and the actuator 20 </ b> B has a first port 21 and a second port 22. The first port 21 and the second port 22 are hydraulic oil supply / discharge ports (supply ports and discharge ports) for the actuator 20. When the hydraulic oil is supplied to the first port 21 and the hydraulic oil is discharged from the second port 22, the actuator 20 operates on one side. Specifically, for example, the hydraulic cylinder extends, and for example, a hydraulic motor (not shown) rotates to one side. When hydraulic oil is supplied to the second port 22 and hydraulic oil is discharged from the first port 21, the actuator 20 operates on the other side (the side opposite to the above “one side”). Specifically, for example, the hydraulic cylinder contracts, and for example, the hydraulic motor rotates to the other side.

  In the hydraulic circuit 1, directional control valves 30 (30A, 30B) each having a different passage pattern are applied. The direction switching valve 30A is disposed between the first pump 11, the second pump 12, and the actuator 20A, and is connected to the first pump 11, the second pump 12, and the actuator 20A. The direction switching valve 30 </ b> A is connected to the tank 15. The direction switching valve 30B is disposed between the first pump 11, the second pump 12, and the actuator 20B, and is connected to the first pump 11, the second pump 12, and the actuator 20B. The direction switching valve 30 </ b> B is connected to the tank 15.

  The direction switching valve 30 </ b> A is disposed downstream of the direction switching valve 30 </ b> B between the first pump 11 and the second pump 12 and the tank 15. The direction switching valve 30A is connected to the first pump 11 and the second pump 12 via unload passages (41, 42) of the direction switching valve 30B. The direction switching valve 30B is connected to the tank 15 via an unload passage (41, 42) of the direction switching valve 30A.

  In the direction switching valve 30A, the first parallel passage 101 is formed in the first parallel region 201, the second parallel passage 102 is formed in the second parallel region 202, and the first tandem passage 301 is formed in the first tandem region 401. The second tandem passage 302 is formed in the second tandem region 402. Therefore, the hydraulic oil discharged from the first pump 11 and the second pump 12 can be supplied to the actuator 20A from the four passages (101, 102, 301, 302) via the bridge passage 53. .

  In the direction switching valve 30 </ b> A, a first passage hole 701 is formed in the first restriction member region 711, a second passage hole 702 is formed in the second restriction member region 712, and a third passage hole 703 is formed in the third restriction member region 713. And a fourth passage hole 704 is formed in the fourth regulating member region 714. The first passage hole 701 is provided with at least a part of a check valve 71 that prevents backflow of hydraulic oil from the bridge passage 53 to the first parallel passage 101. The second passage hole 702 is provided with at least a part of a check valve 72 that prevents backflow of hydraulic oil from the bridge passage 53 to the second parallel passage 102. The third passage hole 703 is provided with at least a part of a check valve 73 that prevents backflow of hydraulic oil from the bridge passage 53 to the first tandem passage 301. The fourth passage hole 704 is provided with at least a part of a check valve 74 that prevents backflow of hydraulic oil from the bridge passage 53 to the second tandem passage 302.

  Here, in the check valve 71, the check valve 72, the check valve 73, and the check valve 74, the throttle amount is set to be different from each other, so that each passage (101, 102, 301, 302) is changed to the bridge passage 53. The priority of the hydraulic oil supply can be adjusted.

  The passages (101, 102, 301, 302) are formed by, for example, cutting. Similarly, formation of the passage holes (701 to 704) is performed by, for example, cutting. In the configuration of the present embodiment, the first parallel passage 101 and the second parallel passage 102 are formed by the first passage hole 701 and the second passage hole 702 after the first passage hole 701 and the second passage hole 702 are formed from outside the valve body 31 with a tool. A tool is formed through the passage hole 701 and the second passage hole 702. Further, the first tandem passage 301 and the second tandem passage 302 are also formed in the third passage hole 703 and the fourth passage after the third passage hole 703 and the fourth passage hole 704 are formed from the outside of the valve body 31 with a tool. It may be formed by a tool through the hole 704.

  On the other hand, in the direction switching valve 30B, the first parallel passage 101 is formed in the first parallel region 201, but the second parallel passage 102 is not formed in the second parallel region 202. In the directional switching valve 30B, the first tandem passage 301 is formed in the first tandem region 401, but the second tandem passage 302 is not formed in the second tandem region 402. Therefore, it is possible to supply hydraulic oil discharged from only the first pump 11 to the actuator 20 </ b> B from the two passages (101, 301) via the bridge passage 53.

  In the direction switching valve 30 </ b> B, the first passage hole 701 is formed in the first restriction member region 711, but the second passage hole 702 is not formed in the second restriction member region 712. In the direction switching valve 30 </ b> B, the third passage hole 703 is formed in the third restriction member region 713, but the fourth passage hole 704 is not formed in the fourth restriction member region 714. The first passage hole 701 is provided with a check valve 71 that prevents backflow of hydraulic oil from the bridge passage 53 to the first parallel passage 101. The third passage hole 703 is provided with a check valve 73 that prevents the backflow of hydraulic oil from the bridge passage 53 to the first tandem passage 301. The passages (101, 301) are formed by, for example, cutting. Similarly, the passage holes (701, 703) are formed by, for example, cutting.

  As described above, according to the direction switching valve 30 (30A, 30B) according to the present embodiment, the first parallel region 201, the second parallel region 202, the first tandem region 401, and the second tandem region 402 are used. By selectively forming one or a plurality of passages (101, 102, 301, 302), a plurality of types of passage patterns for supplying hydraulic oil from the pump to the actuator can be selectively formed. . The direction switching valve 30 can form a passage pattern other than the example shown in the drawings. For example, when only the second parallel passage 102 is formed, it is possible to form a passage pattern in which hydraulic oil from only the second pump 12 is supplied from one passage to the actuator via the bridge passage 52.

  As described above, a plurality of restricting members are formed by opening a plurality of passage holes (701 to 704) through which a plurality of restricting members (check valves (71 to 74) or the like) can pass on the same surface of the valve body 31. Maintenance and various services can be easily performed. In particular, by opening a plurality of passage holes (701 to 704) on the same surface as the surface of the valve body 31 where the actuator passages (61, 62) are opened, maintenance and various services of the plurality of regulating members are further improved. It can be done easily.

  In the service of the regulating member, for example, a check valve (71 to 74) for preventing the backflow of hydraulic oil between the two passages is provided, or a blind plug for blocking communication between the two passages is provided. It is included. Thereby, various selection of a regulating member (check valve (71-74), a blind plug, etc.) is possible, and various desired circuits can be constituted. In the above-described embodiment, oil (working oil) is used as the working fluid, but fluids (including liquid and gas) other than oil may be used as the working fluid.

  In addition, by not arranging the plurality of passage holes (701 to 704) on the same straight line, the plurality of passage holes (701 to 704) and the regulating member installed via the plurality of passage holes (701 to 704) ( Check valves (71 to 74), blind plugs, and the like) can be densely arranged, and the direction switching valve 30 (particularly the valve body 31) can be downsized.

  Such arrangement of the plurality of passage holes (701 to 704) and the regulating member is applicable even in a case where the functions (connection methods) of the plurality of supply passages connectable to the bridge passage are different. The passage may include, for example, a parallel passage and a tandem passage.

  The present invention is not limited to the above-described embodiments and modifications, and can include various aspects to which various modifications that can be conceived by those skilled in the art can be included. The effects achieved by the present invention are also described above. It is not limited to the matter of. Therefore, various additions, modifications, and partial deletions can be made to each element described in the claims and the specification without departing from the technical idea and spirit of the present invention.

DESCRIPTION OF SYMBOLS 1 Construction machine hydraulic circuit 11 1st pump 12 2nd pump 15 Tank 20 Actuator 20A Actuator 20B Actuator 21 1st port 22 2nd port 30 Directional switching valve 30A Directional switching valve 30B Directional switching valve 30a Neutral position 30b 1st operation position 30c Second operation position 31 Valve body 33 Spool hole 41 First unload passage 41a Upstream first unload passage 41b Downstream first unload passage 42 Second unload passage 42a Upstream second unload passage 42b Downstream side Second unload passage 45 Tank passage 51 First supply passage 52 Second supply passage 53 Bridge passage 53a First bridge passage 53b Second bridge passage 55 Bypass passage 61 First actuator passage 62 Second actuator passage 71 Check valve 72 Check valve 73 Check 74 Check valve 80 Spool 81 Notch portion 83 Land portion 101 First parallel passage 102 Second parallel passage 201 First parallel region 202 Second parallel region 301 First tandem passage 302 Second tandem passage 401 First tandem region 402 Second tandem area 701 First passage hole 702 Second passage hole 703 Third passage hole 704 Fourth passage hole 711 First restriction member area 712 Second restriction member area 713 Third restriction member area 714 Fourth restriction member area

Claims (6)

A valve body having a spool hole, a bridge passage connected to the spool hole, and a plurality of supply passages connectable to the bridge passage;
A spool inserted into the spool hole;
A plurality of restricting members that control the flow of hydraulic oil between each of the plurality of supply passages and the bridge passage;
The valve body is formed with a plurality of passage holes through which the plurality of regulating members can pass.
The plurality of passage holes are directional control valves that open on the same surface of the valve body. The valve body further includes an actuator passage connected to the spool hole,
The direction switching valve according to claim 1, wherein the actuator passage opens in the same plane as the plane in which the plurality of passage holes open in the valve body.   The direction switching valve according to claim 1 or 2, wherein the plurality of passage holes are not arranged on the same straight line when viewed from a surface of the valve body where the plurality of passage holes are opened.   The direction switching valve according to any one of claims 1 to 3, wherein the plurality of supply passages include passages having different functions.   The directional control valve according to claim 4, wherein the plurality of supply passages include a parallel-type passage and a tandem-type passage in connection with a working fluid supply source. The direction switching valve according to any one of claims 1 to 5,
A working fluid supply source communicating with the plurality of supply passages of the direction switching valve;
And an actuator communicating with the actuator passage of the direction switching valve.

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