KR20160092935A - Direction converter valve - Google Patents

Abstract

Provided is a direction changing valve capable of selectively forming multiple types of passage patterns to supply oil from a pump to an actuator. A valve body (31) of the direction changing valve (30) includes: a first unload passage (41) connected to a first pump; a second unload passage (42) connected to a second pump; a first supply passage (51) connected to the first pump; a second supply passage (52) connected to a second pump; an actuator passage; a bridge passage (53); an area (201) forming a first parallel passage (101) connecting the passage (51) with the passage (53); an area (202) forming a second parallel passage (102) connecting the passage (52) with the passage (53); an area (401) forming a first tandem passage (301) connecting the passage (41) with the passage (53); and an area (402) forming a second tandem passage (302) connecting the passage (42) with the passage (53). A spool (80) switches connection and disconnection between the bridge passage (53) and the actuator passage.

Description

DIRECTION CONVERTER VALVE

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 (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 supplying and discharging discharged oil of the first pump (10) 2 directional change-over valves (42, 44A, 44B, 44C) for supplying and discharging the discharge oil of the pump (12) to and from the actuator. In this hydraulic circuit, the discharge oil of the first pump 10 and the second pump 12 is supplied to the boom cylinder 24B. A direction switching valve 34C of the first system and a direction switching valve 44B of the second system are connected to the boom cylinder 24B. The discharge oil from the first pump 10 and the second pump 12 is supplied to the arm cylinder 24C. A direction switching valve 34D of the first system and a direction switching valve 44C of the second system are connected to the arm cylinder 24C.

Japanese Unexamined Patent Application Publication No. 10-18360 Japanese Patent Application Laid-Open No. 2013-238291

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

However, in the above configuration, the manufacturing cost of the directional control valve is generated. Therefore, it is sometimes desired to supply oil from two pumps to one actuator by one directional control valve. When such a configuration is realized, the number of the 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, for example, the request for the supply form of the oil from the pump to the actuator may differ depending on the specifications and the like.

Therefore, in one directional control valve, it is possible to selectively form a passage pattern for supplying oil from one pump to one actuator or a passage pattern for supplying oil from one pump to one actuator If possible, the production of the hydraulic circuit can be carried out very advantageously.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a direction switching valve capable of selectively forming a plurality of kinds of passage patterns for supplying oil from an pump to an actuator.

The directional control valve of the present invention includes a valve body having a spool hole and a spool inserted into the spool hole. The valve body includes a first unloading passage opened to the spool hole and connected to the first pump, a second unloading passage opened to the spool hole and connected to the second pump, A second supply passage that is not directly opened to the spool hole but is connectable to the second pump; and a second supply passage that is open to the spool hole and is connected to the actuator A first parallel region capable of forming a first parallel passage connecting the first supply passage and the bridge passage, and a second parallel region provided between the second supply passage and the bridge passage, And a second tandem passage for connecting the first unloading passage and the bridge passage are formed in the second parallel region, And a second tandem region capable of forming a second tandem passage connecting the second unloading passage and the bridge passage. The spool switches connection and disconnection of the bridge passage and the actuator passage according to the position.

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

1 is a side view of a direction switching valve according to an embodiment of the present invention;
Fig. 2 is a longitudinal sectional view of the direction switching valve of Fig. 1; Fig.
3 (A) is a cross-sectional view taken along line III-IIIA shown in FIGS. 1 and 2, and FIG. 3 (B) is a cross-sectional view taken along line III-IIIB shown in FIGS.
4 is a cross-sectional view taken along the line IV-IV shown in Figs. 1 and 2. Fig.
5 is a circuit diagram of the direction switching valve of Fig.
Fig. 6 is a diagram showing a hydraulic circuit for a construction machine to which a plurality of directional switching valves of Fig. 1, in which a passage pattern is formed, is applied.
Fig. 7 is a side view of an example of the directional control valve of Fig. 1, which is included in the hydraulic circuit of Fig. 6;
Fig. 8 is a longitudinal sectional view of the direction switching valve of Fig. 7; Fig.
9A is a cross-sectional view taken along line IXA-IXA shown in Figs. 7 and 8, and Fig. 9B is a cross-sectional view taken along a line IXB-IXB shown in Figs. 7 and 8. Fig.

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

1 to 5 includes a valve body 31 having a spool hole 33 formed therein, a spool 80 inserted into the spool hole 33, And a plurality of regions 201, 202, and 301 capable of forming the passages 101, 102, 301, and 302 are formed in the passages 41, 42, 45, 51, 52, 53, 61, 62 202, 401, 402, and regulating member mounting portions 701 to 704 for installing check valves or blind plugs.

For convenience of explanation, the regions 201 and 202 in the plurality of regions 201, 202, 401, and 402 in which the passages 101, 102, 301, and 302 are formed are surrounded by chain double-dashed lines in Fig. The regions 401 and 402 are surrounded by chain double-dashed lines in Figs. In FIG. 5, the portions corresponding to the regions 201, 202, 401, and 402 are indicated by chain double-dashed lines. The regions 711 and 712 in the regions 711 to 714 in which the regulating member mounting portions 701 to 704 can be formed are surrounded by a one-dot chain line in Fig. The regions 713 and 714 are surrounded by a one-dot chain line in Fig.

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

The passages 101, 102, 301, and 302 that can be formed in the above-described regions 201, 202, 401, and 402 are passages for supplying the discharge oil of the pump to the actuator. When the passage 101, 102, 301, or 302 is formed in at least one of the plurality of regions 201, 202, 401, and 402, the directional control valve 30 supplies and discharges oil to / .

In other words, the directional control valve 30 shown in Figs. 1 to 5 may be referred to as an intermediate body (base body or base member) for manufacturing a directional control valve that is suitably applied to a hydraulic circuit to switch oil. The directional control valve 30 is provided with the plurality of regions 201, 202, 401, and 402 as described above, so that it is possible to selectively form a plurality of kinds of passage patterns for supplying from the pump to the actuator have.

The actuator to which the directional control valve 30 is connected is a hydraulic actuator that operates the construction machine. Types of actuators to which the directional control valve 30 can be connected include a hydraulic motor and a hydraulic cylinder. The actuator to which the directional control valve 30 is connected is an actuator having a first port and a second port. Each of the first port and the second port is a supply port and an oil outlet port for the actuator. Such an actuator operates as one side by supplying oil to the first port and discharging the oil from the second port. Specifically, for example, the hydraulic cylinder is stretched or, for example, the hydraulic motor rotates to one side. The oil is supplied to the second port, and the oil is discharged from the first port, so that the actuator operates on the other side (opposite to the " one side "). Specifically, for example, the hydraulic cylinder is reduced, or, for example, the hydraulic motor rotates to the other side. It is assumed that the directional control valve 30 is connected to such an actuator through an actuator passage 61, 62 which will be described later.

The directional control valve 30 is a spool valve that changes the direction of the oil or the like in accordance with the position (stroke position) of the spool 80 with respect to the spool hole 33. The directional control valve 30 switches the switching position in accordance with the stroke position of the spool 80. [ The switching position of the directional control valve 30 is switched between the neutral position 30a (the position shown in Figs. 2, 4 and 5) and the first operating position 30b ) (See Fig. 5), and a second operating position 30c (see Fig. 5) moved from the neutral position 30a to the left in the figure.

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

The spool hole 33 is formed in (inside of) the valve body 31 (the inside). 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 (flow path, piping) through which oil flows. Each of the plurality of passages 41 to 62 is formed in (inside) the valve body 31 (the inside thereof). The passages 41, 42, 45, 53, 61, and 62 in the plurality of passages 41 to 62 are open to the spool hole 33. [ The openings of the passages 41, 42, 45, 53, 61 and 62 opened in the spool hole 33 to the spool hole 33 extend in the circumferential direction of the spool hole 33, for example. The passages 41, 42, 45, 61 and 62 of the plurality of passages 41 to 62 open on the surface of the valve body 31 so as to communicate with the outside of the valve body 31. The passages 51 and 52 of the plurality of passages 41 to 62 also open on the surface of the valve body 31 so as to communicate with the outside of the valve body 31. [ The unloading passages 41 and 42, the tank passage 45, the supply passage 51 and 52, the bridge passage 53 and the actuator passage 61 and 62 are provided in the plural passages 41 to 62, have.

The unloading passage 41 · 42 is a passage (bypass passage) for returning the discharge oil of the pump to the tank without supplying it to the actuator. However, oil may be supplied to the actuator from the unloading passage 41 · 42 when another passage is branched from the unloading passage 41 · 42 (not shown), for example. Two unloading passages 41 and 42 are provided (so-called dual bypass). The unloading passage 41 · 42 has a first unloading passage 41 and a second unloading passage 42.

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

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

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

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 passage 51 · 52 is a passage for supplying the discharge oil of the pump to the actuator. The supply passage 51 · 52 has a first supply passage 51 and a second supply passage 52.

The first supply passage 51 is a passage connectable to the pump. Further, the first supply passage 51 may not be connected to the pump. The first supply passage 51 does not directly open to the spool hole 33. [ When connected to the pump, the first supply passage 51 is connected to the first pump to which the first unloading passage 41 is connected. The first supply passage 51, when connected to the first pump, receives the discharge oil of the first pump in order to supply the actuator with the discharge oil. The first supply passage 51 may be connected to the first unloading passage 41 (the first upstream unloading passage 41a) when connected to the first pump. In other words, the first supply passage 51 may be connected to the first pump through the first unloading passage 41. In this case, the connection of the first supply passage 51 to the first unloading passage 41 is made outside the directional control valve 30.

The second supply passage 52 is a passage connectable to the pump. Further, the second supply passage 52 may not be connected to the pump. The second supply passage 52 does not directly open to the spool hole 33. [ The second supply passage 52, when connected to the pump, is connected to the second pump to which the second unloading passage 42 is connected. The second supply passage (52), when connected to the second pump, receives the discharge oil of the second pump for supplying to the actuator. The second supply passage 52 may be connected to the second unloading passage 42 (the upstream second unloading passage 42a) when connected to the second pump. In other words, the second supply passage 52 may be connected to the second pump through the second unloading passage 42. In this case, the connection of the second supply passage 52 to the second unloading passage 42 is performed outside the direction switching valve 30.

When the passages 101, 102, 301, and 302 are formed in at least one of the plurality of regions 201, 202, 401, and 402, at least one of the first pump and the second pump And is a passage for supplying the discharge oil from one 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 the discharge fluid from at least one of the first pump and the second pump to the first actuator passage 61 (to be described later). The second bridge passage 53b is a passage for supplying the discharge fluid from at least one of the first pump and the second pump to the second actuator passage 62 (to be described later).

When the passages 101, 102, 301, and 302 are formed in at least one of the plurality of regions 201, 202, 401, and 402, the actuator passages 61 and 62 are provided between the first pump and the second pump And is a passage for supplying the discharge oil from at least one of them to the actuator through the bridge passage 53. [ The actuator passages 61 and 62 are connected to the actuators. The actuator passages 61 and 62 are provided with 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 regions 201, 202, 401, and 402 are regions for forming passages 101, 102, 301, and 302 for supplying the discharged oil of at least one of the first pump and the second pump to the actuator. The first parallel region 201, the second parallel region 202, the first tandem region 401, and the second tandem region 402 are provided in the regions 201, 202, 401, and 402.

The first parallel use region 201 is an area where the first parallel passage 101 connecting the first supply passage 51 and the bridge passage 53 can be formed. The second parallel use region 202 is an area where the second parallel passage 102 connecting the second supply passage 52 and the bridge passage 53 can be formed.

The first tandem region 401 is an area where the first tandem passage 301 connecting the first unloading passage 41 and the bridge passage 53 can be formed. The first tandem passage 301 may connect the first unloading passage 41 and the bridge passage 53 inside the direction switching valve 30. [ The first tandem passage 301 may connect the first unloading passage 41 and the bridge passage 53 from the outside of the directional control valve 30. [ 5, when the first tandem passage 301 is formed, the first unloading passage 41 and the bridge passage 53 are connected to each other inside the directional control valve 30 in the present embodiment, . The second tandem region 402 is an area where the second tandem passage 302 connecting the second unloading passage 42 and the bridge passage 53 can be formed. The second tandem passage 302 may connect the second unloading passage 42 and the bridge passage 53 inside the direction switching valve 30. [ The second tandem passage 302 may connect the second unloading passage 42 and the bridge passage 53 from the outside of the directional control valve 30. [ 5, the second tandem passage 302 is formed by connecting the second unloading passage 42 and the bridge passage 53 from the outside of the directional control 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 use region 202, the bridge passage 53 is connected to the second supply passage 52. When the first parallel path 101 is formed in the first parallel region 201 and the second parallel path 102 is formed in the second parallel region 202, And is connected to the 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 51 It is possible to flow the oil flowing through the pipe. 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 52 It is possible to flow the oil flowing through the pipe. The first parallel passage 101 is formed in the first parallel use region 201 and the first supply passage 51 is connected to the first pump and the second parallel passage 202 is connected to the second parallel passage 102 When the second supply passage 52 is connected to the second pump, the oil flowing in the first supply passage 51 and the oil flowing in the second supply passage 52 are connected to the bridge passage 53, It becomes possible to flow the merged oil.

When the first tandem passage 301 is formed in the first tandem region 401, the bridge passage 53 is connected to the first unloading 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 unloading 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, And is connected to the unloading passage 41 and the second unloading passage 42.

When the first tandem passage 301 is formed in the first tandem region 401, oil flowing through the first unloading passage 41 can flow into the bridge passage 53. When the second tandem passage 302 is formed in the second tandem region 402, the oil flowing through the second unloading passage 42 can flow into 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 oil flowing in the first unloading passage 41 and the oil flowing in the second unloading passage 42 can flow together.

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 401 is connected to the first tandem passage 401. [ The oil flowing in the first supply passage 51 and the oil flowing in the first unloading passage 41 can flow into the bridge passage 53. In this case,

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 and the second tandem passage 402 is connected to the second tandem passage 302 The oil flowing in the second supply passage 52 and the oil flowing in the second unloading passage 42 can flow into the bridge passage 53. In this case,

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 and the first tandem passage 301 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 and the second parallel passage 102 is formed in the second tandem region 402 When the two tandem passages 302 are formed, the oil flowing in the first supply passage 51 and the oil flowing in the first unloading passage 41 are mixed with oil in the bridge passage 53, The oil flowing through the first unloading passage 52 and the oil flowing through the second unloading passage 42 can flow together. It is also possible to prevent the inflow of oil to the bridge passage 53 when at least one of the first parallel passage 101, the second parallel passage 102, the first tandem passage 301 and the second tandem passage 302 is formed There are patterns other than those described above.

As shown in Figs. 2 and 3, the regions 711 to 714 are regions for forming regulating member attaching portions 701 to 704 for installing check valves or blind plugs. The first regulating member region 711 capable of forming the first regulating member attaching portion 701 and the second regulating member region 712 capable of forming the second regulating member attaching portion 702 are formed in the regions 711 through 714, A third regulating member region 713 in which the third regulating member mounting portion 703 can be formed, and a fourth regulating member region 714 in which the fourth regulating member mounting portion 704 can be formed.

2, when the first parallel passage 101 is formed in the first parallel region 201, the first regulatory member region 711 is formed in the first parallel region 101, Is a region for forming a first regulating member mounting portion 701 in which a check valve or a blind plug can be installed between the first regulating member mounting portion 53 and the second regulating member mounting portion 701. When the first parallel passage 101 is formed in the first parallel region 201, the first regulating member mounting portion 701 formed in the first regulating member region 711 has the first regulating member mounting portion 701, And functions as a portion for providing a check valve for preventing back flow of oil to the first parallel passage 101. [ When the first parallel passage 101 formed in the first parallel region 201 becomes unnecessary, the first regulating member installing portion 701 is provided between the bridge passage 53 and the first parallel passage 101 As a part for installing a blind plug for blocking the communication of the blind plug.

The second regulating member region 712 is provided 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. [ Or a second regulating member mounting portion 702 in which a blind plug can be installed. When the first parallel passage 102 is formed in the second parallel region 202, the second regulating member mounting portion 702 formed in the second regulating member region 712 is connected to the bridge passage 53 And functions as a portion for installing a check valve for preventing back flow of oil to the second parallel passage 102. The second restricting member mounting portion 702 is provided on the side of the bridge passage 53 and the second parallel passage 102 in the case where the second parallel passage 102 formed in the second parallel region 202 becomes unnecessary, As a part for installing a blind plug for blocking the communication of the blind plug.

3, when the first tandem passage 301 is formed in the first tandem region 401, the third regulatory member region 713 is formed in the first tandem passage 301, Is a region for forming a third regulating member mounting portion 703 capable of installing a check valve or a blind plug between the first regulating member mounting portion 53 and the second regulating member mounting portion 703. The third regulating member mounting portion 703 formed in the third regulating member region 713 is provided in the first tandem region 401 so as to extend from the bridge passage 53 when the first tandem passage 301 is formed in the first tandem region 401. [ And functions as a portion for installing a check valve for preventing back flow of oil to the first tandem passage 301. [ The third regulating member mounting portion 703 is provided in the vicinity of 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, As a part for installing a blind plug for blocking the communication of the blind plug.

The fourth regulating member region 714 is provided 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. [ Or a fourth regulating member mounting portion 704 in which a blind plug can be installed. The fourth regulating member mounting portion 704 formed in the fourth regulating member region 714 is provided in the second tandem region 402 so as to extend from the bridge passage 53 to the second tandem passage 402 when the second tandem passage 302 is formed in the second tandem region 402. [ And functions as a portion for installing a check valve for preventing back flow of oil to the second tandem passage (302). The fourth regulating member mounting portion 704 is provided in the vicinity of the bridge passage 53 and the second tandem passage 302 when the second tandem passage 401 formed in the second tandem region 402 becomes unnecessary, As a part for installing a blind plug for blocking the communication of the blind plug.

The spool 80 is inserted into the spool hole 33, as shown in Figs. The spool 80 has a substantially cylindrical shape. The axial direction of the spool 80 (the direction of the center axis of the substantially cylindrical body) is referred to as a spool axial direction A. One side in the spool axial direction A is referred to as one side A1 and the other side is referred to as the other side A2. The spool 80 is slidable (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 passages 61 and 62). The spool 80 switches the presence or absence of connection between the passages and the degree of opening (valve opening degree) of the connection. More specifically, the spool 80 places the passages in one of the "blocked state" and the "connected state" (the "fully opened state" and the "throttled state").

Quot; blocked state " is a state in which the passages are not connected to each other (blocked state).

The " connection state " is a state in which the passages are connected (communicated). The " connection state " includes a " fully opened state "

The " fully opened state " is a state in which the opening degree of the passage between the passages is the maximum state (the portion in which the opening degree varies variously when the spool 80 is struck from the end portion of one side A1 to the end portion of the other side A2, State]. For example, the " fully opened state " is a state in which the flow paths of the passages are not tightened.

The " throttling state " is a state in which the flow path between the passages is narrower than the above-mentioned " fully opened state "

The spool 80 adopts a different configuration depending on the patterns of the passages 101, 102, 301, and 302 formed in the plurality of regions 201, 202, 401, Specifically, when the passages 101, 102, 301, and 302 are formed in the bridge passage 53 such that the discharge oil flows from both the first pump and the second pump, and only the first pump In the case where the passages 101, 102, 301 and 302 are formed so as to flow the fluid discharged from the second pump only and the passages 101, 102, 301 and 302 are formed in the bridge passage 53 such that the fluid discharged from only the second pump flows 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, and 302 are formed in the bridge passage 53 such that the discharge oil flows from both the first pump and the second pump .

≪ Case where the discharge oil flows from both the first pump and the second pump in the bridge passage >

In this case, the spool 80 adopts the following configuration.

The spool 80 switches connection and disconnection of the bridge passage 53 and the actuator passage 61, 62.

The spool 80 switches connection and disconnection of the actuator passage 61, 62 and the tank passage 45.

The spool 80 switches connection and disconnection between the upstream first unloading passage 41a and the downstream first unloading passage 41b.

The spool 80 switches connection and disconnection between the upstream side second unloading passage 42a and the downstream side second unloading passage 42b.

4, the spool 80 is provided with a notch 81 and a land 83. [ The notch portion 81 and the land portion 83 are alternately arranged (formed) in the spool axial direction A. [

The cutout portion 81 connects the passages (between the passages). The notch portion 81 connects the openings to the spool holes 33 of the passages. Hereinafter, the opening to the spool hole 33 will be referred to as " opening ". In the illustrated example, the passages 41, 42, 45, 53, 61, and 62 of the plurality of passages 41 to 62 are open to the spool hole 33. The notch portion 81 connects the passages with each other through the spool hole 33. [ 4, the notch portion 81 is a portion recessed inward in the radial direction of the spool 80 with respect to the land portion 83. As shown in Fig. A plurality of notches 81 are provided, for example, four (for example, two, three, or five or more) cutouts may be provided. The cutout portion 81 includes a first unloading passage cutout portion 81a and a second unloading passage cutout portion 81b. The first unloading passage cutout portion 81a connects the upstream first unloading passage 41a and the downstream first unloading passage 41b. The second unloading passage cutout portion 81b, and the upstream second unloading passage 42a and the downstream second unloading passage 42b.

The land portion 83 is in a state in which the passages are not connected (shut-off state). The land portion (83) prevents the cutouts (81) from being connected to each other. The land portion 83 comes into contact with (the inner surface of) the spool hole 33. [ The land portion 83 closes the openings of the passages 41, 42, 45, 53, 61, 62. Alternatively, the land portion 83 blocks the spool hole 33 between the passages. The land portion 83 brings the passages into a contracted state. The land portion 83 makes the openings of the passages 41, 42, 45, 53, 61, and 62 narrower than the fully opened state. A plurality of land portions 83 are provided, for example, five (four or less, or six or more) land portions 83 may be provided. The land portion 83 includes unloading passage land portions 83a to 83c.

The unloading passage land portions 83a to 83c are capable of shutting off the unloading passages 41 and 42 (it is possible to put them into a blocked state). The unloading passage land portions 83a to 83c include a first unloading passage land portion 83a, a second unloading passage land portion 83b and a third unloading passage land portion 83c.

The first unloading passage land portion 83a is in the first operating position 30b (see Fig. 5) moved from the neutral position 30a shown in Fig. 4 to the right in the figure Is set as a cutoff state or a throttle state (not shown). The second unloading passage land portion 83b is in the second operating position 30c (see Fig. 5) that has moved from the neutral position 30a shown in Fig. 4 to the left in the figure Is set as a cutoff state or a throttle state (not shown).

The third unloading passage land portion 83c is capable of shutting off the first unloading passage 41 and shutting off the second unloading passage 42. [ In this configuration, since the third unloading passage land portion 83c is used for two purposes, the land portion can be made common. The third unloading passage land portion 83c has the second unloading passage 42 in a blocking state or a diverging state (not shown) when it is the first operating position 30b. The third unloading passage land portion 83c has the first unloading passage 41 in a shutoff state or a throttling state (not shown) when it is the second operation position 30c. The above is the configuration of the spool 80 in the case where the discharge oil flows from both the first pump and the second pump to the bridge passage 53. [ When the discharge oil flows from one of the first pump and the second pump to the bridge passage 53, the spool 80 adopts the following configuration.

≪ Case in which the discharge oil flows from only the first pump to the bridge passage >

In this case, the spool 80 adopts the following configuration.

The spool 80 switches connection and disconnection of the bridge passage 53 and the actuator passage 61, 62.

The spool 80 switches connection and disconnection of the actuator passage 61, 62 and the tank passage 45.

The spool 80 switches connection and disconnection between the upstream first unloading passage 41a and the downstream first unloading passage 41b.

The spool 80 always brings the upstream side second unloading passage 42a and the downstream side second unloading passage 42b into a connected state at all times.

In this case, the unloading passage land portions 83a to 83c function as follows.

The first unloading passage land portion 83a is in the first operating position 30b (see Fig. 5) moved from the neutral position 30a shown in Fig. 4 to the right in the figure Is set as a cutoff state or a throttle state (not shown). The second unloading passage land portion 83b is in the second operating position 30c (see Fig. 5) that has moved from the neutral position 30a shown in Fig. 4 to the left in the figure (In a fully opened state).

The third unloading passage land portion 83c does not have the function of bringing the second unloading passage 42 into the cutoff state or the contracted state when the first operation position 30b is in the fully opened state. The third unloading passage land portion 83c has the first unloading passage 41 in a shutoff state or a throttling state (not shown) when it is the second operation position 30c.

The other configuration is the same as the configuration in which the discharge oil flows from both the first pump and the second pump to the bridge passage 53.

≪ Case in which the discharge oil flows from only the second pump to the bridge passage >

In this case, the spool 80 adopts the following configuration.

The spool 80 switches connection and disconnection of the bridge passage 53 and the actuator passage 61, 62.

The spool 80 switches connection and disconnection of the actuator passage 61, 62 and the tank passage 45.

The spool 80 always keeps the first upstream unloading passage 41a and the first downstream unloading passage 41b in a connected state.

The spool 80 switches connection and disconnection between the upstream side second unloading passage 42a and the downstream side second unloading passage 42b.

In this case, the unloading passage land portions 83a to 83c function as follows.

The first unloading passage land portion 83a is in the first operating position 30b (see Fig. 5) moved from the neutral position 30a shown in Fig. 4 to the right in the figure (In a fully opened state). The second unloading passage land portion 83b is in the second operating position 30c (see Fig. 5) that has moved from the neutral position 30a shown in Fig. 4 to the left in the figure Is set as a cutoff state or a throttle state (not shown).

The third unloading passage land portion 83c has the second unloading passage 42 in a blocking state or a diverging state (not shown) when it is the first operating position 30b. The third unloading passage land portion 83c does not have the function of bringing the first unloading passage 41 into the shutoff state or the contracted state when the second operation position 30c is in the fully opened state.

The other configuration is the same as the configuration in which the discharge oil flows from both the first pump and the second pump to the bridge passage 53.

[Arrangement of Passages 41 to 62]

The openings of the passages 41, 42, 45, 53, 61, and 62 (the openings to the spool openings 33) that open to the spool openings 33 in the plurality of passages 41 to 62 shown in Fig. From the one side A1 to the other side A2 of the spool axial direction A, for example, in the following order. The tank passage 45, the first actuator passage 61, the first bridge passage 53a (the bridge passage 53 at one side A1), the unloading passage 41 · 42, the second bridge passage 53b, (The bridge passage 53 of the other side A2), the second actuator passage 62, and the tank passage 45 of the other side A2. The opening of the tank passage 45 of the one side A1 and the opening of the tank passage 45 of the other side A2 communicate with each other inside the valve body 31 (it is not necessary to communicate inside the valve body 31).

[Arrangement of unloading passage 41 · 42]

The unloading passages 41 and 42 shown in Fig. 2 are arranged as follows. The unloading passage 41 · 42 is disposed so as to suppress the dimension (the dimension of the spool 80) of the spool hole 33 (see FIG. 2) in the spool axial direction A from becoming too large. Specifically, it is as follows.

[Arrangement order of the unloading passages 41 · 42]

The unloading passage 41 · 42 is provided between the first unloading passage 41 and the second unloading passage 42 when it is necessary to switch connection and disconnection of both the first unloading passage 41 and the second unloading passage 42. [ (Described above) of the third unloading passage land portion 83c in the passage 42. [0064] Specifically, the first unloading passage 41 and the second unloading passage 42 are arranged so as to be adjacent to each other (adjacent to the spool axis direction A, hereinafter the same) (hereinafter, "adjacent"). For example, the downstream first unloading passage 41b and the upstream second unloading passage 42a are disposed adjacent to each other. For example, the first upstream unloading passage 41a and the first downstream unloading passage 41b are disposed adjacent to each other. For example, the upstream-side second unloading passage 42a and the downstream-side second unloading passage 42b are disposed adjacent to each other.

Here, the passage? And the passage? Are " adjacent to each other " as shown in the following [placement example 1] or [placement example 2]. [Arrangement Example 1] No other passage (a passage other than the passage? And the passage?) Is disposed between the passage? And the passage?. In the spool hole 33 (see Fig. 2), no opening of another passage is arranged between the opening of the passage [alpha] (the opening into the spool hole 33) and the opening of the passage [beta]. [Arrangement example 2] The passage? And the passage? Are arranged in order in the spool axial direction A. More specifically, a passage? Is arranged next to passage? (In the order from one side A1 to the other side A2 in the spool axial direction A) (or a passage? Is arranged after passage?). In the spool hole 33 (see Fig. 2), the opening of the passage a and the opening of the passage [beta] are arranged in order in the spool axial direction A. [

1 and 4, the first unloading passage 41 and the second unloading passage 42 extend in the axial direction of the valve body 31 from one side of the valve body 31 to the other side opposite to the side surface, And extends in a direction orthogonal to A. More specifically, in the first unloading passage 41, the upstream first unloading passage 41a extends in the direction perpendicular to the spool axial direction A from the opening side to the spool hole 33, and the valve body 31 And is open to the outside of the valve body 31 in the one side surface of the valve body 31. The downstream first unloading passage 41b is located on the side opposite to the side on which the upstream first unloading passage 41a extends in the direction orthogonal to the spool axial direction A from the opening side to the spool hole 33 And is opened to the outside of the valve body 31 on the other side surface of the valve body 31. In the second unloading passage 42, the upstream second unloading passage 42a extends in the direction perpendicular to the spool axial direction A from the opening side to the spool hole 33, And opens to the outside of the valve body 31 on the side surface. The downstream second unloading passage 42b is located on the side opposite to the side on which the upstream second unloading passage 42a extends in the direction orthogonal to the spool axial direction A from the opening side to the spool hole 33 And is opened to the outside of the valve body 31 on the other side surface of the valve body 31.

[Arrangement of supply passage 51 · 52]

1 and 2, the supply passage 51 · 52 extends along the unloading passage 41 · 42. The supply passage 51 · 52 is disposed radially outward of the unloading passage 41 · 42. The first supply passage 51 extends from the one side of the valve body 31 in which the first unloading passage 41 (the first upstream side unloading passage 41a) opens to the other side. 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 of the valve body 31 in which the second unloading passage 42 (the upstream second unloading passage 42a) opens to the other side. 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 unloading 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 unloading passage (42) and the second supply passage (52) are disposed at positions where at least a part of each other overlaps in the radial direction.

[Arrangement of the bridge passage 53]

2, the first bridge passage 53a is formed in the spool hole 33 when viewed from a cross section orthogonal to the direction in which the unloading passages 41 and 42 and the supply passages 51 and 52 extend. To the outside in the radial direction with respect to the spool axial direction A and then to the second bridge passage 53b along the spool axial direction A. [ The first bridge passage 53a reaches the outer side of the first supply passage 51 in the radial direction. 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 toward the first bridge passage 53a along the spool axial direction A . Then, the second bridge passage 53b reaches the outer side in the radial direction of the second supply passage 52. The first bridge passage 53a and the second bridge passage 53b are connected to each other at radially outer positions of the first supply passage 51 and the second supply passage 52. [

2, the bridge passage 53 is formed in an inverted U-shape. The bridge passage 53 is covered from both sides in the spool axial direction A and from the outside in the radial direction of the unloading passage 41 · 42 and the supply passage 51 · 52. As shown in Fig. 2, the portion of the first bridge passage 53a closer to the connection portion of the second bridge passage 53b and the first supply passage 51 overlap in the radial direction. The portion of the second bridge passage 53b on the connection side with the first bridge passage 53a and the second supply passage 52 overlap in the radial direction. 1, an intermediate portion of the first bridge passage 53a (intermediate position between the opening side of the spool hole 33 and the connection portion of the second bridge passage 53b) and the first The unloading passage 41 (the first upstream unloading passage 41a) is close to the spool axial direction and the radial direction. The intermediate portion of the second bridge passage 53b (intermediate position between the opening side to the spool hole 33 and the connecting portion side of the first bridge passage 53a) and the second unloading passage 42 (the upstream side second unloading passage (42a) are close to each other in the spool axial direction and the radial direction.

[Location of Region 201, 202, 401, 402]

2, a part of the first parallel region 201 faces the first supply passage 51, and another portion of the first parallel region 201 is set at a position facing the bridge passage 53. As shown in Fig. Specifically, the first parallel use region 201 is set between the portion of the first bridge passage 53a on the side of the connection portion with the second bridge passage 53b and the first supply passage 51. That is, the portion of the first bridge passage 53a on the connection side with the second bridge passage 53b, the first parallel region 201, and the first supply passage 51 overlap in the radial direction. Thus, 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 53a toward the first supply passage 51 . The second parallel use region 202 is set at a position where a part of the second parallel use region 202 faces the second supply passage 52 and the other portion faces the bridge passage 53. Concretely, the second parallel use region 202 is set between the portion of the second bridge passage 53b on the side of the connection portion with the first bridge passage 53a and the second supply passage 52. That is, the portion of the second bridge passage 53b closer to the connection portion with the first bridge passage 53a, the second parallel region 202, and the second supply passage 52 overlap in the radial direction. This makes it possible to form the second parallel passage 102 by forming a hole in the second parallel region 202 along the radial direction from the second bridge passage 53b toward the second supply passage 52 .

1 to 3, the first tandem region 401 has a portion thereof facing the outside of the first unloading passage 41 and the valve body 31, and another portion of the first tandem region 401 is connected to the bridge passage 53). Specifically, as shown in Fig. 1, the first tandem region 401 is provided with an intermediate portion of the first bridge passage 53a and the first unloading passage 41 (the first upstream unloading passage 41a) ]. Thus, in the first tandem region 401, an intermediate portion of the first bridge passage 53a from the one side of the valve body 31 and the first unloading passage 41 (the first upstream unloading passage 41a ), The first tandem passage 301 can be formed compactly. When the first tandem passage 301 is connected to the first unloading passage 41 from the outside of the valve body 31, a part of the first tandem region 401 is connected to the first unloading passage 41 ).

The second tandem region 402 is set at a position facing a portion of the second unloading passage 42 and the other portion facing the outside of the valve body 31. Specifically, as shown in Fig. 1, the second tandem region 402 is formed by the intermediate portion of the second bridge passage 53b and the second unloading passage 42 (the downstream second unloading passage 42b) ]. Thus, in the second tandem region 402, an intermediate portion of the second bridge passage 53b from the one side of the valve body 31 and the second unloading passage 42 (the downstream second unloading passage 42b ), The second tandem passage 302 can be formed compactly. When the second tandem passage 302 is connected to the second unloading passage 42 in the valve body 31, a part of the second tandem region 402 is connected to the second unloading passage 42 .

[Location of the regions 711 to 714]

2, when the first parallel passage 101 is formed in the first parallel region 201, the first regulatory member region 711 has the first regulatory member region 711, Of the first parallel passage 101 faces the connection position between the first parallel passage 101 and the bridge passage 53 and the other portion is set at a position facing the outside of the directional control valve 30. [ Thus, the first regulating member mounting 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 directional control valve 30. Thereby, a check valve or a blind plug can be provided between the first parallel passage 101 and the bridge passage 53 from the outside of the directional control valve 30 through the first regulating member attachment portion 701 . Specifically, the first regulating member region 711 includes a portion on the connection side of the first bridge passage 53a to the second bridge passage 53b, a first parallel region 201, And is set in the passage 51 at a position overlapping in the radial direction.

When the second parallel passage 102 is formed in the second parallel region 202, the second regulatory member region 712 is formed so that a part of the second regulatory member region 712 is connected to the second parallel passage 102, And a portion of the other portion is set at a position facing the outside of the directional control valve 30. [0064] As shown in Fig. The second restrictive member mounting portion 702 can be formed as a hole that communicates with the inside of the bridge passage 53, the inside of the second parallel passage 102, and the outside of the directional control valve 30. A check valve or a blind plug can be provided between the second parallel passage 102 and the bridge passage 53 from the outside of the directional control valve 30 through the second restriction member attachment portion 702 . Specifically, the second regulating member region 712 includes a portion of the second bridge passage 53b closer to the connection portion of the first bridge passage 53a, a second parallel region 202, Are set in the passage 52 at positions overlapping in the radial direction.

3A, when the first tandem passage 301 is formed in the first tandem region 401, the third regulating member region 713 is formed in the third tandem region 401, A part of the area 713 faces the connecting position of the first tandem passage 301 and the bridge passage 53 and the other part of the area 713 is set at a position facing the outside of the directional control valve 30. [ The third restriction member mounting portion 703 can be formed as a hole that communicates with the inside of the bridge passage 53, the inside of the first tandem passage 301, and the outside of the directional control valve 30. A check valve or a blind plug can be provided between the first tandem passage 301 and the bridge passage 53 from the outside of the directional control valve 30 through the third restriction member installation portion 703 . Specifically, the third regulatory member region 713 is set at a position overlapping the first tandem region 401 in the direction in which the unloading passages 41 · 42 and the supply passages 51 · 52 extend.

As shown in Fig. 3B, the fourth regulatory member region 714 is a region in which, when the second tandem passage 302 is formed in the second tandem region 402, A part of the area 714 faces the connection position of the second tandem passage 302 and the bridge passage 53 and the other part of the area 714 is set at a position facing the outside of the directional control valve 30. [ Thus, the fourth restriction member mounting 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 directional control valve 30. Thereby, a check valve or a blind plug can be provided between the second tandem passage 302 and the bridge passage 53 from the outside of the directional control valve 30 through the fourth restriction member installation portion 704 . Specifically, the fourth regulatory member region 714 is set at a position overlapping the second tandem region 402 in the direction in which the unloading passageways 41 · 42 and the supply passages 51 · 52 extend.

(work)

The directional control valve 30 can be operated in accordance with the operation of the directional control valve 30 (operation by the operator of the construction machine, for example, lever operation). According to this operation, the direction switching valve 30 switches the neutral position 30a, the first operating position 30b, and the second operating position 30c. According to this operation, the spool 80 shown in Fig. 2 changes the stroke position. As a result, the spool 80 switches the connection between the passages and the degree of opening (valve opening degree) of the connection. When the passages 101, 102, 301, and 302 are formed in at least one of the plurality of regions 201, 202, 401, and 402, at least one of the first pump and the second pump, It is possible to adjust the supply and discharge of oil to and from the actuator and the flow rate of the oil supplied to and discharged from the actuator.

The spool 80 performs different operations by the patterns of the passages 101, 102, 301, and 302 formed in the plurality of regions 201, 202, 401, Specifically, when the passages 101, 102, 301, and 302 are formed in the bridge passage 53 such that the discharge oil flows from both the first pump and the second pump, and only the first pump In the case where the passages 101, 102, 301 and 302 are formed so as to flow the fluid discharged from the second pump only and the passages 101, 102, 301 and 302 are formed in the bridge passage 53 such that the fluid discharged from only the second pump flows And the like. When different operations are performed for each pattern, a spool 80 corresponding to each pattern is used.

≪ Case where the discharge oil flows from both the first pump and the second pump in the bridge passage >

When the passages 101, 102, 301, and 302 are formed in the regions 201, 202, 401, and 402 so that the discharge oil from both the first pump and the second pump flows into the bridge passage 53, The directional control 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 directional control valve 30 brings the first unloading passage 41 into a fully opened state. Specifically, the first upstream unloading passage 41a and the first downstream unloading passage 41b are brought into the fully opened state via the first unloading passage cutout portion 81a (see FIG. 4).

[Operation 1b] The directional control valve 30 brings the second unloading passage 42 into a fully opened state. Specifically, the directional control valve 30 is configured to switch the upstream side second unloading passage 42a and the downstream side second unloading passage 42b through the second unloading passage cutout portion 81b (see FIG. 4) , It is brought into a fully opened state.

[Operation 1c] The directional control valve 30 turns off the bridge passage 53 (first bridge passage 53a and second bridge passage 53b).

[Operation 1d] The directional control valve 30 brings the actuator passage 61 and 62 into a shutoff state.

[Operation 1e] The directional control valve 30 brings the tank passage 45 into a shutoff state.

[Operation 1f] As a result, when the unloading passage 41 · 42 is connected to the tank, the discharged oil of the first pump and the second pump passes through the unloading passage 41 · 42 and returns to the tank . When the actuator passages 61 and 62 are connected to the actuator, the discharged oil of the first pump and the second pump is not supplied to the actuator from the directional control valve 30.

[First operating position 30b]

The direction switching valve 30 when the switching position is the first operating position 30b enters a state of supplying and discharging the oil to the actuator passages 61 and 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 directional control valve 30 sets the first unloading passage 41 to a shutoff state or a throttling state (not shown). Specifically, the directional control valve 30 is configured such that the upstream first unloading passage 41a and the downstream first unloading passage 41b are connected to the first unloading passage land portion 83a (see Fig. 4) , The cutoff state or the throttle state.

[Operation 2b] The directional control valve 30 sets the second unloading passage 42 to a shutoff state or a throttling state (not shown). More specifically, the directional control valve 30 is provided with the upstream second unloading passage 42a and the downstream second unloading passage 42b by the third unloading passage land portion 83c (see Fig. 4) , The cutoff state or the throttle state.

[Operation 2c] The directional control valve 30 brings the first bridge passage 53a (the bridge passage 53) and the first actuator passage 61 into a connected state.

[Operation 2d] The directional control valve 30 turns off the second bridge passage 53b.

[Operation 2e] The directional control valve 30 brings the second actuator passage 62 and the tank passage 45 into a connected state.

[Operation 2f] As a result, the discharged oil of 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, 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 is returned to the tank.

[Second operating position 30c]

The direction switching valve 30 when the switching position is the second operating position 30c enters a state of supplying and discharging the oil to the actuator passages 61 and 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 directional control valve 30 brings the first unloading passage 41 into the shutoff state or the contracted state. Specifically, the directional control valve 30 is provided with the upstream first unloading passage 41a and the downstream first unloading passage 41b by the third unloading passage land portion 83c (see Fig. 2) , The cutoff state or the throttle state.

[Operation 3b] The directional valve 30 sets the second unloading passage 42 to the shutoff state or the throttling state (not shown). Specifically, the directional control valve 30 is provided with the upstream second unloading passage 42a and the downstream second unloading passage 42b by the second unloading passage land portion 83b (see Fig. 2) , The cutoff state or the throttle state.

[Operation 3c] The directional control valve 30 brings the second bridge passage 53b (bridge passage 53) and the second actuator passage 62 into a connected state.

[Operation 3d] The directional control valve 30 brings the first bridge passage 53a into a shutoff state.

[Operation 3e] The directional control valve 30 brings the first actuator passage 61 and the tank passage 45 into a connected state.

[Operation 3f] As a result, the discharged oil of the first pump and the second pump flows into the bridge passage 53. [

[Operation 3g] The oil flowing in the bridge passage 53 flows through the second actuator passage 62. When the second actuator passage 62 is connected to the actuator, 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 is returned to the tank.

≪ Case in which the discharge oil flows from only the first pump to the bridge passage >

When the passages 101, 102, 301, and 302 are formed in the regions 201, 202, 401, and 402 so that only the discharge from the first pump flows in the bridge passage 53, Operates in the following manner in the first operating position 30b.

[Operation 2a-1] The directional control valve 30 sets the first unloading passage 41 to a shutoff state or a throttling state (not shown).

[Operation 2b-1] The directional control valve 30 brings the second unloading passage 42 into a fully opened state.

[Operation 2f-1] The discharge fluid of the first pump flows into the bridge passage 53. The directional control valve 30 operates as follows in the second operating position 30c.

[Operation 3a-1] The directional control valve 30 sets the first unloading passage 41 to a shutoff state or a throttling state (not shown).

[Operation 3b-1] The directional control valve 30 brings the second unloading passage 42 into a fully opened state.

[Operation 3f-1] The discharge fluid of the first pump flows into the bridge passage 53. The other configuration is the same as the configuration in which the discharge oil flows from both the first pump and the second pump to the bridge passage 53.

≪ Case in which the discharge oil flows from only the second pump to the bridge passage >

When the passages 101, 102, 301, and 302 are formed in the regions 201, 202, 401, and 402 so that only the discharge from the second pump flows in the bridge passage 53, Operates in the following manner in the first operating position 30b.

[Operation 2a-2] The directional control valve 30 brings the first unloading passage 41 into a fully opened state.

[Operation 2b-2] The directional valve 30 sets the second unloading passage 42 to the shutoff state or the throttle state (not shown).

[Operation 2f-2] The discharge fluid of the second pump flows into the bridge passage 53. The directional control valve 30 operates as follows in the second operating position 30c.

[Operation 3a-2] The directional control valve 30 brings the first unloading passage 41 into a fully opened state.

[Operation 3b-2] The directional valve 30 sets the second unloading passage 42 to the shutoff state or the throttle state (not shown).

[Operation 3f-2] The discharge fluid of the second pump flows into the bridge passage 53.

The other configuration is the same as the configuration in which the discharge oil flows from both the first pump and the second pump to the bridge passage 53.

(Effect 1)

Effects of the directional control valve 30 shown in Figs. 1 to 5 will be described. The directional control valve 30 includes a valve body 31 having a spool hole 33 and a spool 80 inserted into the spool hole 33. The valve body 31 includes a first unloading passage 41 that opens into the spool hole 33 and is connected to the first pump, a second unloading passage 41 that opens into the spool hole 33, A first supply passage 51 that is not directly opened to the spool hole 33 but is connectable to the first pump and a second supply passage 51 that is not directly opened to the spool hole 33, An actuator passage 61 and 62 opened in the spool hole 33 and connected to the actuator and a bridge passage 53 opened in the spool hole 33. The second supply passage 52 is provided with the second supply passage 52, The valve body 31 further includes a first parallel region 201 capable of forming a first parallel passage 101 connecting the first supply passage 51 and the bridge passage 53 and a second supply passage A second parallel region 202 capable of forming a second parallel passage 102 connecting the first unloading passage 41 and the bridge passage 53 and a second tandem passage connecting the first unloading passage 41 and the bridge passage 53, A second tandem region 402 capable of forming a second tandem passage 302 connecting the second unloading passage 302 and the bridge passage 53, Respectively. The spool 80 switches connection and disconnection between the bridge passage 53 and the actuator passage 61, 62 by its position.

According to this structure, the passages 101, 102, and 301 (not shown) are formed from the first parallel region 201, the second parallel region 202, the first tandem region 401 and the second tandem region 402, , 302) can be selectively formed. Thus, a plurality of types of patterns connecting the pumps (the first pump and the second pump) and the bridge passage 53 can be formed. Then, the spool 80 switches connection and disconnection of the bridge passage 53 and the actuator passage 61, 62 according to the position thereof. This makes it possible to supply the oil from the pump to the bridge passage 53 with a plurality of kinds of passage patterns along the passages 101, 102, 301, and 302 selectively formed. Therefore, according to this directional control valve 30, from the first parallel region 201, the second parallel region 202, the first tandem region 401, and the second tandem region 402, A plurality of kinds of passage patterns for supplying oil from the pump to the actuator can be selectively formed by selectively forming one or a plurality of the passage patterns 101, 102, 301,

(Other effects)

The valve body 31 has the first regulating member region 711, the second regulating member region 712, the third regulating member region 713, and the fourth regulating member region 714 . The first regulating member region 711 is provided 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 a first regulating member mounting portion 701 capable of installing a blind plug. The second regulating member region 712 is provided 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. [ Or a second regulating member mounting portion 702 in which a blind plug can be installed. The third regulating member region 713 is provided 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 a third regulating member mounting portion 703 capable of installing a blind plug. The fourth regulating member region 714 is provided 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. [ Or a fourth regulating member mounting portion 704 in which a blind plug can be installed.

According to this structure, when the first parallel passage 101 is formed in the first parallel region 201, a check valve for preventing back flow of the oil from the bridge passage 53 to the first parallel passage 101 is provided . In this case, oil can be appropriately flown through the hydraulic circuit.

A blind plug that blocks the 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, Can be installed. In this case, the passage pattern for supplying the oil from the pump to the actuator in the direction switching valve 30 can be switched to different passage patterns. The second regulating member region 712, the third regulating member region 713, and the fourth regulating member region 714 also have the same effect as the first regulating member region 711. [

An example in which a plurality of kinds of passage patterns for supplying oil from the pump to the actuator are selectively formed in the directional control valve 30 will be described below.

6 shows a hydraulic circuit 1 for a construction machine (hereinafter referred to as a hydraulic circuit 1) to which a plurality of directional control valves 30 (30A, 30B) in Fig. 1 in which a passage pattern is formed is applied. The hydraulic circuit 1 is a hydraulic circuit used in a construction machine (not shown). Construction machinery is a machine for carrying out construction work. The construction machine is, for example, a hydraulic shovel. As shown in Fig. 6, the hydraulic circuit 1 includes a pump 11 占 2, a tank 15, an actuator 20 (20A, 20B) And directional control valves 30 (30A, 30B).

The pump 11 · 12 is a hydraulic pump that discharges oil (pressurized oil, hydraulic oil). The pump 11 · 12 has a capacity variable type. In the pump 11 · 12, the capacity is changed by changing the tilting angle of the swash plate, and when the capacity is changed, the discharge amount (discharge amount of oil per one rotation of the input shaft) is changed. The pump 11 · 12 is composed of two pumps. The pump 11 · 12 includes a first pump 11 and a second pump 12. The pump 11 · 12 is, for example, a split pump. The split pump is a pump in which a plurality of pumps (the first pump 11 and the second pump 12) are driven by one input shaft. In the split pump, the first pump 11 and the second pump 12 are integrally formed. In the split pump, the discharge amount of the first pump 11 and the discharge amount of the second pump 12 are equal. Further, the pump 11 · 12 does not have to be a split pump. 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 be common or not 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 the oil. The tank 15 supplies oil to the pump 11 · 12. The oil that has been discharged from the pump 11 · 12 and passed through the actuator 20 is returned to the tank 15. The oil discharged from the pump 11 · 12 and not passed through the actuator 20 is returned to the tank 15.

The actuator 20 actuates the construction machine. The actuator 20 is a hydraulic actuator that is driven by supply of oil from the pump 11 · 12. The actuator 20 is driven by supplying oil from at least one of the first pump 11 and the second pump 12. When the construction machine is a hydraulic excavator, the use of the actuator 20 includes driving, turning, bucket rotation, arm taking, and boom taking.

The actuator 20A in the drawing is, for example, a hydraulic cylinder (arm cylinder) for lifting (lifting and lowering) the arm relative to the boom. The actuator 20B is, for example, a hydraulic motor (orbiting motor) for turning the upper revolving structure 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 a supply port and a discharge port for the oil to the actuator 20. The oil is supplied to the first port 21 and the oil is discharged from the second port 22, so that the actuator 20 operates as one side. Specifically, for example, the hydraulic cylinder is stretched or, for example, a hydraulic motor (not shown) is rotated to one side. The oil is supplied to the second port 22 and the oil is discharged from the first port 21 so that the actuator 20 operates on the other side (the side opposite to the "one side"). Specifically, for example, the hydraulic cylinder is reduced, or, for example, the hydraulic motor rotates to the other side.

In the hydraulic circuit 1, the directional control valves 30 (30A and 30B) of Fig. 1 in which different passage patterns are formed are applied. The directional control valve 30A is disposed between the first pump 11 and the second pump 12 and the actuator 20A and the first pump 11 and the second pump 12 and the actuator 20A . The directional control valve 30A is connected to the tank 15. The directional control valve 30B is disposed between the first pump 11 and the second pump 12 and the actuator 20B and the first pump 11 and the second pump 12 and the actuator 20B . The directional control valve 30B is connected to the tank 15.

The directional control valve 30A is disposed on the downstream side of the directional control valve 30B between the first pump 11 and the second pump 12 and the tank 15. [ The directional control valve 30A is connected to the first pump 11 and the second pump 12 through the unloading passages 41 and 42 of the directional control valve 30B. The directional control valve 30B is connected to the tank 15 through the unloading passages 41 and 42 of the directional control valve 30A.

In the directional control valve 30A, the first parallel passage 101 is formed in the first parallel region 201. As shown in Fig. And a second parallel passage 102 is formed in the second parallel use region 202. A first tandem passage (301) is formed in the first tandem region (401). And a second tandem passage 302 is formed in the second tandem region 402. Therefore, it is possible to supply the discharged oil of the first pump 11 and the second pump 12 from the four passages 101, 102, 301, and 302 to the actuator 20A through the bridge passage 53 .

In the directional control valve 30A, the first regulating member mounting portion 701 is formed in the first regulating member region 711. [ And the second regulating member mounting portion 702 is formed in the second regulating member region 712. [ And the third regulating member mounting portion 703 is formed in the third regulating member region 713. [ And the fourth regulating member mounting portion 704 is formed in the fourth regulating member region 714. [ A check valve 71 for preventing back flow of the oil from the bridge passage 53 to the first parallel passage 101 is provided in the first regulating member mounting portion 701. A check valve 72 for preventing back flow of the oil from the bridge passage 53 to the second parallel passage 102 is provided in the second restriction member mounting portion 702. A check valve 73 for preventing back flow of oil from the bridge passage 53 to the first tandem passage 301 is provided in the third regulating member mounting portion 703. A check valve 74 for preventing back flow of oil from the bridge passage 53 to the second tandem passage 302 is provided in the fourth regulating member mounting portion 704.

In the check valve 71, the check valve 72, the check valve 73 and the check valve 74, the amount of the throttling is set differently for each of the passages 101, 102, 301 and 302 To be supplied to the bridge passage 53 with priority.

7 to 9 show the state in which the first parallel passage 101, the second parallel passage 102, the first tandem passage 301 and the second tandem passage 302 are formed, the state of the first regulating member mounting portion 701 The check valve 71, the check valve 72, the check valve 72, and the check valve 72 are formed in the state that the first regulating member mounting portion 702, the third regulating member mounting portion 703, 73 and the check valve 74 are shown. The passages 101, 102, 301 and 302 are formed by, for example, cutting. Likewise, the mounting portions 701 to 704 are formed by, for example, cutting. The first parallel passage 101 and the second parallel passage 102 are formed such that the first regulating member mounting portion 701 and the second regulating member mounting portion 702 are located on the side of the valve body 31 Is formed by a tool from the outside, passes through the first regulating member mounting portion 701 and the second regulating member mounting portion 702, and is formed by a tool.

6, the first parallel passage 101 is formed in the first parallel region 201 in the directional control valve 30B. The second parallel passage 102 is not formed in the second parallel use region 202. A first tandem passage (301) is formed in the first tandem region (401). And the second tandem passage 302 is not formed in the second tandem region 402. Therefore, it is possible to supply the discharged oil of only the first pump 11 from the two passages 101, 301 to the actuator 20B through the bridge passage 53. [

In the directional control valve 30B, the first regulating member mounting portion 701 is formed in the first regulating member region 711. [ The second regulating member mounting portion 702 is not formed in the second regulating member region 712. [ And the third regulating member mounting portion 703 is formed in the third regulating member region 713. [ The fourth regulating member mounting portion 704 is not formed in the fourth regulating member region 714. [ A check valve 71 for preventing back flow of the oil from the bridge passage 53 to the first parallel passage 101 is provided in the first regulating member mounting portion 701. A check valve 73 for preventing back flow of oil from the bridge passage 53 to the first tandem passage 301 is provided in the third regulating member mounting portion 703. The passages 101 and 301 are formed, for example, by cutting. Likewise, the mounting portions 701 and 703 are formed by, for example, cutting.

1, the first parallel region 201, the second parallel region 202, the first tandem region 401, and the second tandem region 402, A plurality of kinds of passage patterns for supplying oil from the pump to the actuator can be selectively formed by selectively forming one or a plurality of passages 101, 102, 301, In the directional 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, a passage pattern for supplying the discharged oil from only the second pump 12 to the actuator through the bridge passage 52 from one passage can be formed Do.

1: Hydraulic circuit for construction machine
11: first pump
12: Second pump
15: Tank
20, 20A, 20B: actuators
21: First Photo
22: The second photo
30, 30A, 30B: Direction switching valve
30a: Neutral position
30b: first operating position
30c: second operating position
31: Valve body
33: Spool hole
41: 1st unloading passage
41a: upstream side first unloading passage
41b: downstream first unloading passage
42: 2nd unloading passage
42a: upstream-side second unloading passage
42b: downstream side second unloading 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 passage
71, 72, 73, 74: Check valve
80: spool
81:
81a: cutout portion for the first unloading passage
81b: cutout portion for the second unloading passage
83: RANBU
83a: a first unloading passage land portion
83b: a land portion for the second unloading passage
83c: Land portion for the third unloading passage
101: first parallel passage
102: second parallel passage
201: area for the first parallel area
202: area for the second parallel area
301: first tandem passage
302: second tandem passage
401: area for the first tandem
402: area for the second tandem
701: first regulating member mounting portion
702: second regulating member mounting portion
703: Third regulation member mounting portion
704: Fourth restriction member mounting portion
711: area for the first regulating member
712: area for the second regulating member
713: area for the third regulating member
714: region for the fourth regulating member

Claims (1)

A valve body having a spool hole formed therein,
And a spool inserted in the spool hole,
Wherein the valve body comprises:
A first unloading passage opened to the spool hole and connected to the first pump,
A second unloading passage opened to the spool hole and connected to the second pump,
A first supply passage which is not directly opened to the spool hole but is connectable to the first pump,
A second supply passage which is not directly opened to the spool hole but is connectable to the second pump,
An actuator passage opened to the spool hole and connected to the actuator,
A bridge passage opened to the spool hole,
A first parallel region in which a first parallel passage connecting the first supply passage and the bridge passage can be formed,
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 unloading passage and the bridge passage,
And a second tandem region capable of forming a second tandem passage connecting the second unloading passage and the bridge passage,
Wherein the spool switches connection and disconnection of the bridge passage and the actuator passage according to the position thereof.

Images