JP2016138619A - Directional switching valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a directional selecting valve capable of selectively forming a plurality of types of passage patterns to supply oil from a pump to an actuator.SOLUTION: A valve body 31 of a directional selecting valve 30 includes a first unload passage 41 connected to a first pump, a second unload passage 41 connected to a second pump, a first supply passage 51 connectable to the first pump, a second supply passage 52 connectable to the second pump, an actuator passage, a bridge passage 53, a region 201 where a first parallel passage 101 can be formed to connect the passage 51 and the passage 53, a region 202 where a second parallel passage 102 can be formed to connect the passage 52 and the passage 53, a region 401 where a first tandem passage 301 can be formed to connect the passage 41 and the passage 53, and a region 402 where a second tandem passage 302 can be formed to connect the passage 42 and the passage 53. A spool 80 selects the bridge passage 53 to be connected to/disconnected from the actuator passage.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a direction switching valve.

  Conventionally, there is a hydraulic circuit in which oil is supplied from two pumps to one actuator (for example, Patent Document 1 and Patent Document 2). For example, the hydraulic circuit described in Patent Document 1 includes a first system direction switching valve (32, 34A, 34B, 34C, 34D) for discharging and discharging discharged oil of the first pump (10) to the actuator, And a second direction switching valve (42, 44A, 44B, 44C) for discharging and discharging oil discharged from the pump (12) to the actuator. In this hydraulic circuit, the oil discharged from the first pump (10) and the second pump (12) is supplied to the boom cylinder (24B). A first system direction switching valve (34C) and a second system direction switching valve (44B) are connected to the boom cylinder (24B). Also, the discharge oil from the first pump (10) and the second pump (12) is supplied to the arm cylinder (24C). A first direction switching valve (34D) and a second direction switching valve (44C) are connected to the arm cylinder (24C).

Japanese Patent Laid-Open No. 10-18360 JP 2013-238291 A

  As described above, in the prior art, in order to supply oil from two pumps to one actuator, two directional control valves are connected to one actuator. That is, one directional control valve is used to supply oil from one pump to one actuator. Such a configuration may be desirable depending on the specifications of the hydraulic circuit, for example.

  However, in the above configuration, the manufacturing cost of the direction switching valve is increased. Therefore, it may be desired to supply oil from two pumps to one actuator with a single direction switching valve. When such a configuration is realized, the number of directional control valves used in the hydraulic circuit can be reduced, so that there is an advantage that the manufacturing cost can be suppressed.

  As described above, in the hydraulic circuit, the demand for the supply mode of oil from the pump to the actuator may differ depending on, for example, its specifications.

  Therefore, in one directional control valve, a passage pattern for supplying oil from one pump to one actuator, a passage pattern for supplying oil from two pumps to one actuator, etc. are selectively formed. If possible, the production of the hydraulic circuit can be carried out very advantageously.

  The present invention has been made in view of the above circumstances, and an object thereof is to provide a direction switching valve capable of selectively forming a plurality of types of passage patterns for supplying oil from a pump to an actuator.

  The direction switching valve according to the present invention includes a valve body in which a spool hole is formed, and a spool inserted into the spool hole. The valve body opens to the spool hole and is connected to a first pump; a second unload passage that opens to the spool hole and is connected to a second pump; and the spool hole A first supply passage that can be connected to the first pump without opening directly, a second supply passage that can be connected to the second pump without opening directly to the spool hole, and the spool hole An actuator passage connected to the actuator, a bridge passage opening to the spool hole, and a first parallel region capable of forming a first parallel passage connecting the first supply passage and the bridge passage; A second parallel region capable of forming a second parallel passage connecting the second supply passage and the bridge passage, and a first tank connecting the first unload passage and the bridge passage. It has a first tandem region capable of forming a beam path, and the second unloading passage and the bridge passage and capable of forming a second tandem passage connecting a second tandem region. The spool switches connection and disconnection between the bridge passage and the actuator passage according to the position of the spool.

  According to the present invention, a plurality of types of passage patterns for supplying oil from the pump to the actuator can be selectively formed.

It is a side view of the direction switching valve concerning one embodiment of the present invention. It is a longitudinal cross-sectional view of the direction switching valve of FIG. (A) is sectional drawing which follows the IIIA-IIIA line | wire shown to FIG. 1 and FIG. (B) is sectional drawing which follows the IIIB-IIIB line | wire shown to FIG. 1 and FIG. It is sectional drawing which follows the IV-IV line | wire shown in FIG. 1 and FIG. It is a circuit diagram of the direction switching valve of FIG. It is a figure which shows the hydraulic circuit for construction machines with which the direction switching valve of FIG. 1 with which the passage pattern was formed was applied in multiple numbers. It is a side view of an example of the direction switching valve of FIG. 1 included in the hydraulic circuit of FIG. It is a longitudinal cross-sectional view of the direction switching valve of FIG. (A) is sectional drawing which follows the IXA-IXA line | wire shown to FIG. 7 and FIG. (B) is sectional drawing which follows the IXB-IXB line | wire shown to FIG. 7 and FIG.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

  The direction switching valve 30 according to the present embodiment shown in FIGS. 1 to 5 includes a valve body 31 in which a spool hole 33 is formed, a spool 80 inserted in the spool hole 33, and a plurality of passages (41, 42, 45, 51, 52, 53, 61, 62 (hereinafter referred to as (41-62))) and a plurality of regions (201, 202, 401, 402) and a plurality of regions (711 to 714) capable of forming restriction member installation portions (701 to 704) for providing check valves or blind plugs.

  For convenience of explanation, the passage (201, 202) among the plurality of regions (201, 202, 401, 402) in which the passage (101, 102, 301, 302) can be formed is surrounded by a two-dot chain line in FIG. It is. The passages (401, 402) are surrounded by a two-dot chain line in FIGS. In FIG. 5, portions corresponding to the regions (201, 202, 401, 402) are indicated by two-dot chain lines. Moreover, the area | region (711,712) of the some area | regions (711-714) which can form a control member installation part (701-704) is enclosed with the dashed-dotted line in FIG. The region (713, 714) is surrounded by a one-dot chain line in FIG.

  The direction switching valve 30 is a direction switching valve applied to a construction machine hydraulic circuit (not shown). The direction switching valve 30 is connected to a pump (not shown) and an actuator (not shown) in a hydraulic circuit for construction machinery, and is a valve for supplying and discharging (supplying and discharging) oil to and from the actuator.

  The passages (101, 102, 301, 302) that can be formed in the above regions (201, 202, 401, 402) are passages for supplying pump discharge oil to the actuator. The direction switching valve 30 supplies and discharges 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, the direction switching valve 30 shown in FIGS. 1 to 5 can be said to be an intermediate body (base body or base member) for manufacturing a direction switching valve that is applied to a hydraulic circuit and appropriately switches oil. The direction switching valve 30 includes a plurality of regions (201, 202, 401, 402) as described above, so that a plurality of types of passage patterns for supplying the actuator from the pump can be selectively formed. It 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 that can be connected to the direction switching valve 30 include 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 an oil supply / discharge port (supply port and discharge port) for the actuator. Such an actuator operates on one side when oil is supplied to the first port and 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 oil is supplied to the second port and oil is discharged from the first port, the actuator 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. The direction switching valve 30 is assumed to be connected to such an actuator via an actuator passage (61, 62) described later.

  The direction switching valve 30 is a spool valve that changes the direction of oil or the like in accordance with the position (stroke position) of the spool 80 with respect to the spool hole 33. The direction switching valve 30 switches the switching position according to the stroke position of the spool 80. The switching position of the direction switching valve 30 includes a neutral position 30a (the position shown in FIGS. 2, 4 and 5), and a first operating position 30b (see FIG. 5) moved from the neutral position 30a to the right side in the drawing. And a second operating position 30c (see FIG. 5) moved from the neutral position 30a to the left side in the figure.

  The valve body 31 is a portion where the spool hole 33, the passages (41 to 62), the regions (201, 202, 401, 402), and the regions (711 to 714) are formed. The valve body 31 has a block shape (block shape).

  The spool hole 33 is formed in (inside) the valve main 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 oil flows. Each of the plurality of passages (41 to 62) is formed in (inside) the valve body 31. Of the plurality of passages (41 to 62), the passages (41, 42, 45, 53, 61, 62) open to the spool hole 33. The opening to the spool hole 33 of the passage (41, 42, 45, 53, 61, 62) that opens to the spool hole 33 extends in the circumferential direction of the spool hole 33, for example. 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 to 62) also open to the surface of the valve body 31 so as to communicate with the outside of the valve body 31. The plurality of passages (41-62) include an unload passage (41, 42), a tank passage 45, a supply passage (51, 52), a bridge passage 53, and an actuator passage (61, 62). is there.

  The unload passages (41, 42) are passages (bypass passages) for returning the pump discharge oil to the tank without supplying it to the actuator. However, for example, when another passage branches from the unload passage (41, 42) (not shown), oil may be supplied from the unload passage (41, 42) to the actuator. Two unload passages (41, 42) are provided (so-called dual bypass). The unload passage (41, 42) includes 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 second unload passage 42b. 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.

  The tank passage 45 is a passage connected to a tank (not shown). The tank passage 45 is a passage for returning the oil discharged from the actuator 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.

  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 discharge oil of 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 second supply passage 52 receives the discharged oil of the second pump to supply 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). This is a passage for supplying the oil discharged from either to the actuator. As shown in FIG. 2, the bridge passage 53 includes a first bridge passage 53a and a second bridge passage 53b. The first bridge passage 53a is a passage for supplying discharged oil from at least one of the first pump and the second pump to the first actuator passage 61 (described below). The second bridge passage 53b is a passage for supplying discharged oil from at least one of the first pump and the second pump to the second actuator passage 62 (described below).

  The actuator passage (61, 62) is a first pump and a second pump when the passage (101, 102, 301, 302) is formed in at least one of the plurality of regions (201, 202, 401, 402). This is a passage for supplying discharged oil from at least one of the actuators to the actuator via the bridge passage 53. The actuator passage (61, 62) is 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 the discharge oil of 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 and the bridge passage 53 can be formed. The second parallel region 202 is a region where the second parallel passage 102 that connects the second supply passage 52 and 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 and 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. As shown in FIG. 5, in the present embodiment, 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 and 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. As shown in FIG. 5, in the present embodiment, when the second tandem passage 302 is formed, the second unload passage 42 and the bridge passage 53 are connected outside 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, oil flowing through the first supply passage 51 flows in the bridge passage 53. Is possible. 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, oil flowing through the second supply passage 52 flows in the bridge passage 53. Is possible. 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 can flow oil in which oil flowing through the first supply passage 51 and oil flowing through the second supply passage 52 merge.

  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, 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, 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. It becomes possible for the oil, which is a combination of the oil and the oil flowing through the second second unload passage 42, to 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, oil that is a mixture of the oil flowing through the first supply passage 51 and the oil flowing through the first unload passage 41 can flow.

  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, oil in which oil flowing through the second supply passage 52 and oil flowing through 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: Oil in which the oil flowing in the first supply passage 51 and the oil flowing in the first unload passage 41 merge, and the oil in which the oil flowing in the second supply passage 52 and the oil flowing in the second unload passage 42 merge. It becomes possible to flow. The oil inflow pattern 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 includes patterns other than those described above. To do.

  As shown in FIGS. 2 and 3, the regions (711 to 714) are regions for forming restricting member installation portions (701 to 704) for providing check valves or blind plugs. The regions (711 to 714) include a first restricting member region 711 capable of forming the first restricting member installing portion 701, a second restricting member region 712 capable of forming the second restricting member installing portion 702, and a third restricting member. There is a third restricting member region 713 capable of forming the member installing portion 703 and a fourth restricting member region 714 capable of forming the fourth restricting member installing portion 704.

  As shown in FIG. 2, the first restricting member region 711 has a check valve between the first parallel passage 101 and the bridge passage 53 when the first parallel passage 101 is formed in the first parallel region 201. Or it is an area | region for forming the 1st control member installation part 701 which can provide a blind plug. The first restricting member installation portion 701 formed in the first restricting member region 711 is configured such that when the first parallel passage 101 is formed in the first parallel region 201, the bridge passage 53 to the first parallel passage 101 is provided. It functions as a part that provides a check valve that prevents backflow of oil. The first restricting member installation portion 701 is a blind plug that blocks communication between the bridge passage 53 and the first parallel passage 101 when the first parallel passage 101 formed in the first parallel region 201 becomes unnecessary, for example. It functions as a part to provide.

  The second restricting member region 712 may be provided with a check valve or a blind plug between the second parallel passage 102 and the bridge passage 53 when the second parallel passage 102 is formed in the second parallel region 202. This is an area for forming a possible second restricting member installation portion 702. When the first parallel passage 102 is formed in the second parallel region 202, the second restriction member installation portion 702 formed in the second restricting member region 712 is connected to the second parallel passage 102 from the bridge passage 53. It functions as a part that provides a check valve that prevents backflow of oil. The second restricting member installing portion 702 is a blind plug that blocks communication between the bridge passage 53 and the second parallel passage 102 when the second parallel passage 102 formed in the second parallel region 202 becomes unnecessary, for example. It functions as a part to provide.

  As shown in FIG. 3, the third restricting member region 713 includes a check valve between the first tandem passage 301 and the bridge passage 53 when the first tandem passage 301 is formed in the first tandem region 401. Or it is an area | region for forming the 3rd control member installation part 703 which can provide a blind plug. When the first tandem passage 301 is formed in the first tandem region 401, the third restricting member installation portion 703 formed in the third restricting member region 713 is connected to the first tandem passage 301 from the bridge passage 53. It functions as a part that provides a check valve that prevents backflow of oil. The third restricting member installation portion 703 is a blind plug that blocks communication between the bridge passage 53 and the first tandem passage 301 when the first tandem passage 301 formed in the first tandem region 401 becomes unnecessary, for example. It functions as a part to provide.

  The fourth restriction member region 714 may be provided with a check valve or a blind plug between the second tandem passage 302 and the bridge passage 53 when the second tandem passage 302 is formed in the second tandem region 402. This is an area for forming a possible fourth restricting member installation portion 704. When the second tandem passage 302 is formed in the second tandem region 402, the fourth restricting member installation portion 704 formed in the fourth restricting member region 714 is connected to the second tandem passage 302 from the bridge passage 53. It functions as a part that provides a check valve that prevents backflow of oil. The fourth restricting member installation portion 704 is a blind plug that blocks communication between the bridge passage 53 and the second tandem passage 302 when, for example, the second tandem passage 401 formed in the second tandem region 402 becomes unnecessary. It functions as a part to provide.

  As shown in FIGS. 2 and 4, the spool 80 is inserted into the spool hole 33. 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” and a “connected state” (“fully open state” and “throttle state”).
The “blocked state” is a state where the passages are not connected (blocked state).
The “connected state” is a state where the passages are connected (communication 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 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 passages between the passages are not restricted.
The “squeezed state” is a state where the flow path between the passages is narrower than the “fully open state” (excluding the shut-off state).

  The spool 80 has a different configuration 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 discharge oil from both the first pump and the second pump flows, the first pump is provided in the bridge passage 53. When the passages (101, 102, 301, 302) are formed so that the discharge oil from only the first pump flows, and the passages (101, 102, 301, 302) so that the discharge oil from only the second pump flows through the bridge passage 53. 302) is formed, a spool having a different configuration is used.

  The spool 80 shown in FIGS. 1 to 5 is used when the passages (101, 102, 301, 302) are formed in the bridge passage 53 so that the discharge oil from both the first pump and the second pump flows. Shows the spool.

<In the case where the oil discharged from both the first pump and the second pump flows 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 passage (61, 62).
The spool 80 switches connection and disconnection between the actuator passage (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.

  As shown in FIG. 4, the spool 80 includes a notch portion 81 and a land portion 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, 61, 62) of the plurality of passages (41 to 62) open to the spool hole 33. The notch 81 connects the passages through the spool hole 33. As shown in FIG. 4, the notch portion 81 is a portion that is recessed inward in the radial direction of the spool 80 with respect to the land portion 83. A plurality of the notches 81 are provided, for example, four places (two places, three places, or five or more places may be provided). The cutout portion 81 includes a first unload passage cutout portion 81a and a second unload passage cutout portion 81b. The first unload passage notch 81a connects the upstream first unload passage 41a and the downstream first unload passage 41b. The notch 81b 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 contacts the spool hole 33 (the inner surface thereof). The land portion 83 closes the opening of the passage (41, 42, 45, 53, 61, 62). Alternatively, the land portion 83 closes the spool hole 33 between the passages. The land portion 83 places the passages in a throttled state. The land part 83 makes the opening of the passage (41, 42, 45, 53, 61, 62) narrower than the fully opened state. A plurality of land portions 83 are provided, for example, 5 locations (4 locations or less, or 6 locations or more may be provided). The land portion 83 includes unload passage land portions (83a to 83c).

  The unload path land portions (83a to 83c) can block the unload path (41, 42) (can be in a blocked state). The unload passage land portions (83a to 83c) include a first unload passage land portion 83a, a second unload passage land portion 83b, and a third unload passage land portion 83c.

  When the first unload passage land portion 83a is in the first operation position 30b (see FIG. 5) moved from the neutral position 30a shown in FIG. Set to the aperture state (not shown). When the second unload passage land portion 83b is in the second operating position 30c (see FIG. 5) moved from the neutral position 30a shown in FIG. Set to the aperture state (not shown).

  The third unload passage land portion 83 c can block the first unload passage 41 and can block the second unload passage 42. In this configuration, since the third unload passage land portion 83c is used for two purposes, the land portion can be shared. The third unload passage land portion 83c places 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 83c puts the first unload passage 41 into a cut-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 the discharged oil from both the first pump and the second pump flows through the bridge passage 53. In the case where the discharged oil from either the first pump or the second pump flows through the bridge passage 53, the spool 80 has the following configuration.

<In the case where the oil discharged from only the first pump flows 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 passage (61, 62).
The spool 80 switches connection and disconnection between the actuator passage (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 portions (83a to 83c) function as follows.

  When the first unload passage land portion 83a is in the first operation position 30b (see FIG. 5) moved from the neutral position 30a shown in FIG. Set to the aperture state (not shown). When the second unload passage land portion 83b is in the second operating position 30c (see FIG. 5) moved from the neutral position 30a shown in FIG. Does not have a function to set the aperture state (maintains fully open).

  The third unload passage land portion 83c does not have a function of keeping the second unload passage 42 in the cut-off state or the throttle state (maintained in the fully open state) when the first operation position 30b is reached. The third unload passage land portion 83c puts the first unload passage 41 into a cut-off state or a throttled state (not shown) at the second operating position 30c.

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

<In the case where the discharge oil from only the second pump flows 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 passage (61, 62).
The spool 80 switches connection and disconnection between the actuator passage (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 portions (83a to 83c) function as follows.

  When the first unload passage land portion 83a is in the first operation position 30b (see FIG. 5) moved from the neutral position 30a shown in FIG. Does not have a function to set the aperture state (maintains fully open). When the second unload passage land portion 83b is in the second operating position 30c (see FIG. 5) moved from the neutral position 30a shown in FIG. Set to the aperture state (not shown).

  The third unload passage land portion 83c places 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 83c does not have a function of keeping the first unload passage 41 in the shut-off state or the throttled state at the second operating position 30c (maintains the fully opened state).

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

(Arrangement of passages (41-62))
The openings (openings to the spool hole 33) of the passages (41, 42, 45, 53, 61, 62) that open to the spool hole 33 among the plurality of passages (41 to 62) shown in FIG. For example, they are arranged in the following order from one side A1 to the other side A2 of A. One side A1 tank passage 45, first actuator passage 61, first bridge passage 53a (one side A1 bridge passage 53), unload passage (41, 42), second bridge passage 53b (the other side A2 bridge passage) 53), the second actuator passage 62, 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 body 31 (it is not necessary to communicate with each other inside the valve body 31).

(Arrangement of unload passage (41, 42))
The unload passages (41, 42) shown in FIG. 2 are arranged as follows. The unload passages (41, 42) are arranged so that the size of the spool hole 33 (see FIG. 2) in the spool axial direction A (the size of the spool 80) can be suppressed from becoming too large. Specifically, it is as follows.

(Arrangement order of unload passages (41, 42))
The unload passages (41, 42) are connected to and disconnected from both the first unload passage 41 and the second unload passage 42 when the first unload passage 41 and the second unload passage 42 are switched. Thus, the third unload passage land portion 83c is arranged so as to 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) (“adjacent” is described below). 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 passage α and passage β) is placed between passage α and passage β. In the spool hole 33 (see FIG. 2), no other passage opening is 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 axis 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 (see FIG. 2), the opening of the passage α and the opening of the passage β are sequentially arranged in the spool axial direction A.

  As shown in FIGS. 1 and 4, the first unload passage 41 and the second unload passage 42 are 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. It extends to. 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))
As shown in FIGS. 1 and 2, the supply passages (51, 52) extend along the unload passages (41, 42). The supply passages (51, 52) are disposed radially outside 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 51 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))
As shown in FIG. 2, 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 It extends outward in the radial direction with respect to the direction A, and then extends 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.

  In the cross-sectional view shown in FIG. 2, 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. As shown in FIG. 2, the portion of the first bridge passage 53 a on the connection portion side with the second bridge passage 53 b 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, in a side view shown in FIG. 1, the intermediate portion of the first bridge passage 53a (the intermediate position between the opening side to the spool hole 33 and the connection portion side of the second bridge passage 53b) and the first unload passage 41 ( The upstream first unload passage 41a) is close to the spool in the axial direction and the 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)
As shown in FIG. 2, the first parallel region 201 is set so that 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. Accordingly, 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. Thus, 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.

  As shown in FIGS. 1 to 3, part of the first tandem region 401 faces the outside of the first unload passage 41 and the valve body 31, and the other part faces the bridge passage 53. Set to position. Specifically, as shown in FIG. 1, 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). Is done. As a result, in the first tandem region 401, a hole is formed between an intermediate portion of the first bridge passage 53a and the first unload passage 41 (upstream first unload passage 41a) from one side surface of the valve body 31. By forming, the 1st tandem channel | path 301 can be formed compactly. 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, as shown in FIG. 1, the second tandem region 402 is set between the intermediate portion of the second bridge passage 53b and the second unload passage 42 (upstream second unload passage 42a). Is done. As a result, in the second tandem region 402, a hole is formed between an intermediate portion of the second bridge passage 53b and the second unload passage 42 (upstream second unload passage 42a) from one side surface of the valve body 31. By forming, the 2nd tandem channel | path 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))
As shown in FIG. 2, when the first parallel path 101 is formed in the first parallel region 201, the first restricting member region 711 has a part of the first restricting member region 711 that The first parallel passage 101 and the bridge passage 53 face a connection position, and the other part is set to a position facing the outside of the direction switching valve 30. Accordingly, the first restricting member installation portion 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, a check valve or a blind plug can be provided between the first parallel passage 101 and the bridge passage 53 through the first restriction member installation portion 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. In addition, it is set at 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. The other part is set at a position facing the outside of the direction switching valve 30. Accordingly, the second restricting member installation portion 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, a check valve or a blind plug can be provided between the second parallel passage 102 and the bridge passage 53 through the second restricting member installation portion 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, a second parallel region 202, and a second supply passage 52. In addition, it is set at a position overlapping in the radial direction.

  As shown in FIG. 3A, the third restricting member region 713 is a part of the third restricting member region 713 when the first tandem passage 301 is formed in the first tandem region 401. However, it faces the connection position of the first tandem passage 301 and the bridge passage 53, and the other part is set to a position facing the outside of the direction switching valve 30. Thus, the third restricting member installation portion 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. Accordingly, a check valve or a blind plug can be provided between the first tandem passage 301 and the bridge passage 53 through the third restriction member installation portion 703 from the outside of the direction switching valve 30. Specifically, the third restricting member region 713 is set at a position overlapping the first tandem region 401 in the direction in which the unload passages (41, 42) and the supply passages (51, 52) extend.

  As shown in FIG. 3B, the fourth regulating member region 714 is a part of the fourth regulating member region 714 when the second tandem passage 302 is formed in the second tandem region 402. However, it faces the connection position between the second tandem passage 302 and the bridge passage 53, and the other part is set at a position facing the outside of the direction switching valve 30. Accordingly, the fourth restricting member installation portion 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. Accordingly, a check valve or a blind plug can be provided between the second tandem passage 302 and the bridge passage 53 through the fourth restriction member installation portion 704 from the outside of the direction switching valve 30. Specifically, the fourth restriction member region 714 is set at a position overlapping the second tandem region 402 in the direction in which the unload passages (41, 42) and the supply passages (51, 52) extend.

(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 shown in FIG. 2 changes the stroke position. As a result, the spool 80 switches the presence / absence of connection between the passages and the opening degree (valve opening degree) of the connection. And when a channel | path (101,102,301,302) is formed in at least any one of several area | regions (201,202,401,402), from at least any one of a 1st pump and a 2nd pump. It is possible to adjust the presence / absence of supply / discharge (supply and discharge) of oil to and from the actuator and the flow rate of 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 discharge oil from both the first pump and the second pump flows, the first pump is provided in the bridge passage 53. When the passages (101, 102, 301, 302) are formed so that the discharge oil from only the first pump flows, and the passages (101, 102, 301, 302) so that the discharge oil from only the second pump flows through the bridge passage 53. Different operations are performed when 302) is formed. When performing different operations for each pattern, the spool 80 corresponding to each pattern is used.

<In the case where the oil discharged from both the first pump and the second pump flows through the bridge passage>
When the passage (101, 102, 301, 302) is formed in the region (201, 202, 401, 402) so that the discharge 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] As shown in FIG. 2, 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 81a (see FIG. 4).
[Operation 1b] The direction switching valve 30 fully opens the second unload passage 42. Specifically, the direction switching valve 30 connects the upstream second unload passage 42a and the downstream second unload passage 42b via a second unload passage notch 81b (see FIG. 4). Fully open.
[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 discharged oil of the first pump and the second pump passes through the unload passage (41, 42) and returns to the tank. It will be in a state to be. When the actuator passage (61, 62) is connected to the actuator, the discharge oil of 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 oil is supplied to and discharged from the actuator passage (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 is configured to shut off the upstream first unload passage 41a and the downstream first unload passage 41b by the first unload passage land portion 83a (see FIG. 4). Set to the aperture state.
[Operation 2b] The direction switching valve 30 brings the second unload passage 42 into a cutoff state or a throttle state (not shown). Specifically, the direction switching valve 30 is configured to shut off the upstream second unload passage 42a and the downstream second unload passage 42b by the third unload passage land portion 83c (see FIG. 4). Set to the aperture state.
[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 oil discharged from the first pump and the second pump flows into the bridge passage 53.
[Operation 2g] The 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 oil flowing through the first actuator passage 61 is supplied to the actuator. The oil discharged from the actuator flows through the tank passage 45 through the second actuator passage 62. The 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 where oil is supplied to and discharged from the actuator passage (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 is configured to shut off the upstream first unload passage 41a and the downstream first unload passage 41b by the third unload passage land portion 83c (see FIG. 2). Set to the aperture state.
[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 is configured to shut off the upstream second unload passage 42a and the downstream second unload passage 42b by the second unload passage land portion 83b (see FIG. 2). Set to the aperture state.
[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 oil discharged from the first pump and the second pump flows into the bridge passage 53.
[Operation 3g] The 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 oil flowing through the second actuator passage 62 is supplied to the actuator. The oil discharged from the actuator flows through the tank passage 45 through the first actuator passage 61. The oil flowing through the tank passage 45 returns to the tank.

<In the case where the oil discharged from only the first pump flows through the bridge passage>
When the passage (101, 102, 301, 302) is formed in the region (201, 202, 401, 402) so that only the discharge 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 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 3f-1] The oil discharged from the first pump flows into the bridge passage 53.

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

<In the case where the discharge oil from only the second pump flows through the bridge passage>
When the passage (101, 102, 301, 302) is formed in the region (201, 202, 401, 402) so that only the discharge 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 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 shut-off state or a throttled state (not shown).
[Operation 3f-2] The oil discharged from the second pump flows into the bridge passage 53.

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

(Effect 1)
The effect of the direction switching valve 30 shown in FIGS. 1 to 5 will be described. The direction switching valve 30 includes a valve main body 31 in which a spool hole 33 is formed, and a spool 80 inserted into the spool hole 33. The valve body 31 opens to the spool hole 33 and is connected to the first pump. The first unload passage 41 is connected to the first pump. The second unload passage 42 is connected to the second pump and connected to the second pump. A first supply passage 51 that does not directly open to the hole 33 and can be connected to the first pump; a second supply passage 52 that does not directly open to the spool hole 33 and can be connected to the second pump; and a spool It has an actuator passage (61, 62) that opens to the hole 33 and is connected to the actuator, and a bridge passage 53 that opens to the spool hole 33. The valve body 31 further includes a first parallel region 201 capable of forming a first parallel passage 101 that connects the first supply passage 51 and the bridge passage 53, and a second connection passage 52 that connects the second supply passage 52 and the bridge passage 53. A second parallel region 202 capable of forming the two parallel passages 102, a first tandem region 401 capable of forming the first tandem passage 301 connecting the first unload passage 41 and the bridge passage 53, A second tandem region 402 capable of forming a second tandem passage 302 that connects the load passage 302 and the bridge passage 53. The spool 80 switches between connection and disconnection of the bridge passage 53 and the actuator passage (61, 62) depending on the position thereof.

  According to this configuration, the passage (101, 102, 301, 302) is selectively selected from the first parallel region 201, the second parallel region 202, the first tandem region 401, and the second tandem region 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 between connection and disconnection of the bridge passage 53 and the actuator passage (61, 62) depending on the position. Thereby, 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 directional 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 oil from the pump to the actuator can be selectively formed.

(Other effects)
The valve main body 31 includes a first restricting member region 711, a second restricting member region 712, a third restricting member region 713, and a fourth restricting member region 714. The first restricting member region 711 may be provided with a check valve or a blind plug between the first parallel passage 101 and the bridge passage 53 when the first parallel passage 101 is formed in the first parallel region 201. This is an area for forming a possible first restricting member installation portion 701. The second restricting member region 712 may be provided with a check valve or a blind plug between the second parallel passage 102 and the bridge passage 53 when the second parallel passage 102 is formed in the second parallel region 202. This is an area for forming a possible second restricting member installation portion 702. When the first tandem passage 301 is formed in the first tandem region 401, the third restricting member region 713 may be provided with a check valve or a blind plug between the first tandem passage 301 and the bridge passage 53. This is an area for forming a possible third restricting member installation portion 703. The fourth restriction member region 714 may be provided with a check valve or a blind plug between the second tandem passage 302 and the bridge passage 53 when the second tandem passage 302 is formed in the second tandem region 402. This is an area for forming a possible fourth restricting member installation portion 704.

  According to this configuration, when the first parallel passage 101 is formed in the first parallel region 201, it is possible to provide a check valve that prevents backflow of oil from the bridge passage 53 to the first parallel passage 101. In this case, the oil can be properly flowed in the hydraulic circuit. In addition, for example, when the first parallel passage 101 formed in the first parallel region 201 is not necessary, a blind plug that blocks communication between the bridge passage 53 and the first parallel passage 101 can be provided. In this case, the passage pattern for supplying 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 also have the same effect as the first restricting member region 711.

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

  FIG. 6 shows a construction machine hydraulic circuit 1 (hereinafter referred to as a hydraulic circuit 1) to which a plurality of the directional control valves 30 (30A, 30B) of FIG. The hydraulic circuit 1 is a hydraulic circuit used for a construction machine (not shown). A construction machine is a machine for performing construction work. The construction machine is, for example, a hydraulic excavator. As shown in FIG. 6, the hydraulic circuit 1 includes a pump (11, 12), a tank 15, an actuator 20 (20 </ b> A, 20 </ b> B), and a direction switching valve 30 (FIG. 1 to FIG. 5) in which a passage pattern is formed. 30A, 30B).

  The pumps (11, 12) are hydraulic pumps that discharge oil (pressure oil, hydraulic oil). The pumps (11, 12) are of a variable capacity type. In the pumps (11 and 12), the capacity changes by changing the tilt angle of the swash plate, and the discharge amount (the oil discharge amount per one rotation of the input shaft) changes when the capacity changes. The pump (11, 12) is 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 oil. The tank 15 supplies oil to the pumps (11 and 12). The oil discharged from the pump (11, 12) and returned to the tank 15 is returned to the tank 15. Oil discharged from the pump (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 is a hydraulic actuator that is driven by oil supplied from the pumps (11, 12). The actuator 20 is driven by oil supplied from at least one of the first pump 11 and the second pump 12. When the construction machine is a hydraulic excavator, applications of the actuator 20 include traveling, turning, bucket rotating, arm raising and lowering, and boom raising and lowering.

  The actuator 20A in the drawing is, as an example, 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 20A and the actuator 20B has a first port 21 and a second port 22. Each of the first port 21 and the second port 22 is an oil supply / discharge port (supply port and discharge port) for the actuator 20. When the oil is supplied to the first port 21 and the oil is discharged from the second port 22, the actuator 20 operates to one side. Specifically, for example, the hydraulic cylinder extends, and for example, a hydraulic motor (not shown) rotates to one side. When oil is supplied to the second port 22 and oil is discharged from the first port 21, the actuator 20 operates on the other side (opposite side 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, the direction switching valve 30 (30A, 30B) of FIG. 1 in which different passage patterns are formed is 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 an unload passage (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 30 </ b> A, the first parallel passage 101 is formed in the first parallel region 201. A second parallel passage 102 is formed in the second parallel region 202. A first tandem passage 301 is formed in the first tandem region 401. A second tandem passage 302 is formed in the second tandem region 402. Therefore, the 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 restriction member installation portion 701 is formed in the first restriction member region 711. A second restricting member installation portion 702 is formed in the second restricting member region 712. A third restricting member installation portion 703 is formed in the third restricting member region 713. A fourth restricting member installation portion 704 is formed in the fourth restricting member region 714. The first restricting member installation portion 701 is provided with a check valve 71 that prevents backflow of oil from the bridge passage 53 to the first parallel passage 101. The second restricting member installation portion 702 is provided with a check valve 72 that prevents backflow of oil from the bridge passage 53 to the second parallel passage 102. The third regulating member installation portion 703 is provided with a check valve 73 that prevents backflow of oil from the bridge passage 53 to the first tandem passage 301. The fourth regulating member installation portion 704 is provided with a check valve 74 that prevents backflow of oil from the bridge passage 53 to the second tandem passage 302.

  Here, the check valve 71, the check valve 72, the check valve 73, and the check valve 74 are set so that the throttle amounts are different from each other, so that any of the passages (101, 102, 301, 302) is changed to the bridge passage 53. It is possible to adjust whether oil is supplied with priority.

  7 to 9, the first parallel passage 101, the second parallel passage 102, the first tandem passage 301 and the second tandem passage 302 are formed, a first restricting member installing portion 701, and a second restricting member installing portion 702. The formation state of the third restriction member installation portion 703 and the fourth restriction member installation portion 704 and the arrangement state of the check valve 71, the check valve 72, the check valve 73, and the check valve 74 are shown. The passages (101, 102, 301, 302) are formed by, for example, cutting. Similarly, the installation portions (701 to 704) are formed by cutting, for example. In the configuration of the present embodiment, the first parallel passage 101 and the second parallel passage 102 are formed after the first restricting member installing portion 701 and the second restricting member installing portion 702 are formed from the outside of the valve body 31 with a tool. The first restricting member installing portion 701 and the second restricting member installing portion 702 are formed by tools.

  As shown in FIG. 6, in the direction switching valve 30 </ b> B, the first parallel passage 101 is formed in the first parallel region 201. The second parallel passage 102 is not formed in the second parallel region 202. A first tandem passage 301 is formed in the first tandem region 401. The second tandem passage 302 is not formed in the second tandem region 402. Therefore, the discharge oil of only the first pump 11 can be supplied to the actuator 20B from the two passages (101, 301) via the bridge passage 53.

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

  As described above, according to the direction switching valve 30 in FIG. 1, the passage (101, 101) is 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 a plurality of (102, 301, 302), a plurality of types of passage patterns for supplying oil from the pump to the actuator can be selectively formed. In the direction switching valve 30, a plurality of passage patterns can be formed in addition to the examples shown in FIGS. For example, when only the second parallel passage 102 is formed, it is possible to form a passage pattern in which discharged oil from only the second pump 12 is supplied from one passage to the actuator via the bridge passage 52.

DESCRIPTION OF SYMBOLS 1 Construction machinery hydraulic circuit 11 1st pump 12 2nd pump 15 Tank 20, 20A, 20B Actuator 21 1st port 22 2nd port 30, 30A, 30B Directional switching valve 30a Neutral position 30b 1st operation position 30c 2nd 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 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 61 first actuator passage 62 second actuator passages 71, 72, 73, 74 check valve 80 spool 81 off Notch 81a first unload passage notch 81b first Unload passage cutout 83 Land portion 83a First unload passage land portion 83b Second unload passage land portion 83c Third first unload passage 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 region 701 First restriction member installation portion 702 Second restriction member installation portion 703 Third Restriction member installation portion 704 Fourth restriction member installation portion 711 First restriction member region 712 Second restriction member region 713 Third restriction member region 714 Fourth restriction member region

Claims (1)

A valve body in which a spool hole is formed;
A spool inserted into the spool hole,
The valve body is
A first unload passage that opens in the spool hole and is connected to the first pump;
A second unload passage that opens into the spool hole and is connected to a second pump;
A first supply passage that does not open directly into the spool hole and is connectable to the first pump;
A second supply passage that does not open directly into the spool hole and is connectable to the second pump;
An actuator passage that opens into the spool hole and is connected to the actuator;
A bridge passage that opens into the spool hole;
A first parallel region capable of forming a first parallel passage connecting the first supply passage and the bridge passage;
A second parallel region capable of forming a second parallel passage connecting the second supply passage and the bridge passage;
A first tandem region capable of forming a first tandem passage connecting the first unload passage and the bridge passage;
A second tandem region capable of forming a second tandem passage connecting the second unload passage and the bridge passage,
The spool is a directional control valve that switches connection and disconnection between the bridge passage and the actuator passage according to the position of the spool.

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