Multi-control valve and construction machine including same

Abstract

This multi-control valve comprises: a valve block including a first pump port, a second pump port, first to fourth connection ports, and a tank port; a plurality of spools, each controlling a flow of hydraulic fluid to a corresponding actuator; and a plurality of spool covers provided in the valve block to cover the plurality of spools, respectively. The valve block includes a first surface to a fifth surface. The plurality of spool covers are provided on the first surface and the second surface. The first pump port and the first connection port are formed on the third surface. The second pump port and the second connection port are formed on the fourth surface. The tank port and the third and fourth connection ports are formed on the fifth surface.

Description

Multi-control valve and construction machine equipped with same

[0001] The present disclosure relates to a multi-control valve that controls the flow of hydraulic fluid to an actuator, and a construction machine equipped with the same.

[0002] Construction machines such as excavators are equipped with multiple actuators, such as a travel motor, a boom cylinder, and an arm cylinder, and perform various tasks by driving the multiple actuators. One example of such a construction machine is disclosed in Patent Document 1. In addition to the multiple actuators, the construction machine disclosed in Patent Document 1 is also equipped with two pumps, a tank, and a multi-control valve. The multi-control valve is connected to each of the two pumps, the tank, and the actuators, and drives each of the actuators by controlling the flow of hydraulic fluid to each of the actuators.

[0003] Japanese Patent Application Laid-Open No. 2020-133692

[0004] The multi-control valve for construction machinery disclosed in Patent Document 1 includes a valve block through which a spool is slidably inserted. A plurality of ports are formed on each side of the valve block, and each port is connected to an actuator, a pump, a tank, or the like via piping or the like. The ports include a pump port connected to the pump, a tank port connected to the tank, and actuator ports connected to each of the actuators. The pump port and the tank port are arranged together on one side of the valve block, for example, on the rear surface, and the actuator ports are arranged side by side on the left and right side surfaces.

[0005] On the other hand, multi-control valves are required to be compact. In the multi-control valves mentioned above, the actuator ports are simply arranged side by side on the left and right sides, so to make the valve block smaller, the distance between the actuator ports must be shortened. However, this causes the pipes connected to the actuator ports to interfere with each other, making it difficult to make the valve block smaller.

[0006] Therefore, an object of the present disclosure is to provide a multi-control valve that can achieve a compact valve block by adjusting the layout of each port, and a construction machine equipped with the same.

[0007] The multi-control valve of the present disclosure is a multi-control valve connected to a first pump, a second pump, first to fourth actuators, and a tank, and controls the flow of hydraulic fluid to each of the first to fourth actuators, and includes a valve block including a first pump port connected to the first pump, a second pump port connected to the second pump, first to fourth connection ports connected to each of the first to fourth actuators, and a tank port connected to the tank; and a valve block provided in the valve block so as to be slidable in a first direction, corresponding to each of the first to fourth actuators, and connected to the corresponding actuator, at least one of the first pump and the second pump, and the tank, and and a plurality of spool covers provided on the valve block so as to cover the plurality of spools, wherein the valve block includes a first surface and a second surface on one side and the other side in the first direction, a third surface and a fourth surface on one side and the other side in a second direction intersecting the first direction, and a fifth surface on one side in a third direction intersecting the first and second directions, and the plurality of spool covers are provided on the first surface and the second surface, the first pump port and the first connection port are formed on the third surface, the second pump port and the second connection port are formed on the fourth surface, and the tank port and the third and fourth connection ports are formed on the fifth surface.

[0008] According to the present disclosure, the first pump port and the first connection port are formed on the third surface, and the second pump port and the second connection port are formed on the fourth surface. Furthermore, the tank port and the third and fourth connection ports are formed on the fifth surface. Therefore, the ports connected to the actuators can be distributed and formed on the third to fifth surfaces. This allows the valve block to be made smaller. That is, the layout of each port can achieve a smaller valve block.

[0009] The construction machine disclosed herein comprises a boom cylinder that drives a boom, an arm cylinder that drives an arm, a traveling device including first and second traveling motors, and the aforementioned multi-control valve, wherein the first connection port is a port connected to the boom cylinder, the second connection port is a port connected to the arm cylinder, the third connection port is a port connected to the first traveling motor, and the fourth connection port is a port connected to the second traveling motor.

[0010] According to the present disclosure, the construction machine is provided with the above-described multi-control valve, which allows the installation space of the multi-control valve to be reduced in the construction machine.

[0011] According to the multi-control valve and construction machine of the present disclosure, the layout of each port can achieve miniaturization of the valve block.

[0012] The above and other objects, features, and advantages of the present disclosure will become apparent from the following detailed description of preferred embodiments, which proceeds with reference to the accompanying drawings.

[0013] 1. A perspective view showing a construction machine according to the present disclosure. 2. A plan view showing a construction machine according to the present disclosure. 3. A circuit diagram showing a hydraulic circuit of a hydraulic drive unit provided in a construction machine. 4. A perspective view showing a multi-control valve provided in a hydraulic drive unit of a first embodiment according to the present disclosure. 5. A side view of the multi-control valve of FIG. 3 as seen from one side in the height direction. 6. A side view of the multi-control valve of FIG. 3 as seen from the other side in the height direction. 7. A perspective view of the multi-control valve of FIG. 3 as seen from a different direction. 8. A cross-sectional view of the multi-control valve of FIG. 6 taken along line A-A. 9. A cross-sectional view of the multi-control valve of FIG. 6 taken along line B-B. 10. A cross-sectional view of the multi-control valve of FIG. 6 taken along line C-C. 11. A cross-sectional view of the multi-control valve of FIG. 6 taken along line D-D. 12. An enlarged plan view showing the multi-control valve provided in the construction machine of FIG. 2. 13. A perspective view of a multi-control valve provided in a hydraulic drive unit of a second embodiment according to the present disclosure. 14. A perspective view of the multi-control valve of FIG. 13 taken from a different direction.

[0014] A construction machine 1 and a multi-control valve 10, 110 provided therewith according to an embodiment of the present disclosure will be described below with reference to the drawings. Note that the concepts of directions used in the following description are used for convenience of explanation and do not limit the orientation of the configuration of the present disclosure to those directions. Furthermore, the construction machine 1 and multi-control valve 10, 110 described below are merely one embodiment of the present disclosure. Therefore, the present disclosure is not limited to the embodiment, and additions, deletions, and modifications are possible within the scope of the spirit of the present disclosure.

[0015] [First Embodiment] The construction machine 1 shown in FIG. 1 is equipped with a multi-control valve 10 as shown in FIG. 2. The construction machine 1 is, for example, a shovel. However, the construction machine 1 may also be a wheel loader, a crane, or the like. The construction machine 1 is configured, for example, as follows. That is, as shown in FIG. 1, the construction machine 1 is equipped with a traveling device 101, a revolving body 102, a boom 103, an arm 104, and a bucket 105. The traveling device 101 includes, for example, a pair of crawlers 101L, 101R. However, the traveling device 101 may include multiple wheels instead of the pair of crawlers 101L, 101R. Each of the crawlers 101L, 101R can be driven to move in various directions. The revolving body 102 is provided on the traveling device 101 so as to be revolvable about a rotation axis L1 extending in the vertical direction. The boom 103 is provided on the revolving body 102 so as to be swingable in the vertical direction. The arm 104 is provided at the tip of the boom 103 so as to be swingable in the front-to-rear direction. Furthermore, the bucket 105 is provided at the tip of the arm 104 so as to be swingable in the front-to-rear direction or the up-to-down direction. The front-to-rear direction is the direction in which the boom 103 extends, and the left-to-right direction is the direction perpendicular to the front-to-rear direction and the up-to-down direction.

[0016] The construction machine 1 also includes a plurality of actuators 2 to 7 shown in FIG. 3 for driving the traveling device 101, the revolving unit 102, the boom 103, the arm 104, and the bucket 105. In this embodiment, the excavator includes a first traveling motor 2, a second traveling motor 3, a swing motor 4, a boom cylinder 5, an arm cylinder 6, and a bucket cylinder 7. However, the excavator may include actuators other than the six described above. The first traveling motor 2 and the second traveling motor 3 operate the pair of crawlers 101L, 101R provided on the traveling device 101, respectively. The swing motor 4 rotates the revolving unit 102. Furthermore, the boom cylinder 5, the arm cylinder 6, and the bucket cylinder 7 are provided on the boom 103, the arm 104, and the bucket 105, respectively. That is, the boom cylinder 5, the arm cylinder 6, and the bucket cylinder 7 are disposed on the front side of the revolving unit 102. The boom cylinder 5, arm cylinder 6, and bucket cylinder 7 respectively operate the boom 103, arm 104, and bucket 105. The construction machine 1 also includes a hydraulic drive unit 100 for supplying hydraulic fluid to the actuators 2 to 7 to drive them.

[0017] <Hydraulic Drive Unit> The hydraulic drive unit 100 supplies hydraulic fluid to each of the actuators 2 to 7 to drive them. More specifically, the hydraulic drive unit 100 includes two hydraulic pumps 8 and 9, a drive source E, a multi-control valve 10, and a tank 30. The two hydraulic pumps 8 and 9 are, for example, variable displacement swash plate pumps that discharge hydraulic fluid. In this embodiment, the hydraulic pumps 8 and 9 are configured as a tandem pump connected to each other. Note that the two hydraulic pumps 8 and 9 do not necessarily have to be configured as a tandem pump and may be two single pumps. Furthermore, the two hydraulic pumps 8 and 9 may be other variable displacement pumps, such as bent-axis pumps, or may be fixed displacement pumps. The drive source E drives the two hydraulic pumps 8 and 9. In this embodiment, the drive source E is an engine, which is connected to the two hydraulic pumps 8 and 9 via a drive shaft. The drive source E drives the two hydraulic pumps 8 and 9 via a drive shaft, thereby discharging hydraulic fluid from the two hydraulic pumps 8 and 9. Note that the drive source E is not limited to an engine, and may be another drive source such as an electric motor.

[0018] <Multi-Control Valve> The multi-control valve 10 shown in FIG. 4 is, for example, a multi-control valve for a two-pump system. The multi-control valve 10 is connected to two hydraulic pumps 8 and 9 as shown in FIG. 3. The hydraulic fluid is supplied to the multi-control valve 10 from the two hydraulic pumps 8 and 9. The multi-control valve 10 is also connected to a plurality of actuators 2 to 7 and controls the flow of hydraulic fluid to each of the actuators 2 to 7. That is, the multi-control valve 10 controls the direction (i.e., flow direction) of hydraulic fluid supplied to and discharged from each of the actuators 2 to 7, as well as the flow rate of the hydraulic fluid supplied and discharged. More specifically, each of the actuators 2 to 7 has two ports 2a to 7a and 2b to 7b. The multi-control valve 10 controls the flow of hydraulic fluid to each of the two ports 2a to 7a and 2b to 7b in each of the actuators 2 to 7. More specifically, the multi-control valve 10 can independently control the flow rates of hydraulic fluid supplied to and discharged from two ports 4a to 7a and two ports 4b to 7b in each of the swing motor 4, boom cylinder 5, arm cylinder 6, and bucket cylinder 7. The multi-control valve 10 configured in this manner includes a valve block 11 and a plurality of spools 12 to 25, as shown in FIGS. 5 and 6 . In this embodiment, the multi-control valve 10 includes fourteen spools 12 to 25. The number of spools 12 to 25 included in the multi-control valve 10 is not limited to fourteen, and may be thirteen or fewer, or fifteen or more. The multi-control valve 10 also includes a boom regeneration valve element 26.

[0019] As shown in FIGS. 4 and 7 , the valve block 11 is formed, for example, in the shape of a rectangular parallelepiped. That is, the valve block 11 includes first to sixth surfaces 11A to 11F. The first surface 11A and the second surface 11B are surfaces located on one side and the other side of the height direction, which is an example of a first direction, in the valve block 11. The third surface 11C and the fourth surface 11D are surfaces located on one side and the other side of the width direction, which is an example of a second direction, in the valve block 11. The fifth surface 11E and the sixth surface 11F are surfaces located on one side and the other side of the depth direction, which is an example of a third direction, in the valve block 11. The height direction, width direction, and depth direction are perpendicular to each other. However, the first to third directions do not necessarily have to be perpendicular to each other and may intersect each other. In addition, in this embodiment, various ports 31a, 32a, 33a, 33b, 35a, 36a, 38a, 39a, 41a, 41b, 43a, 45a, 45b, 47a, 49a, 50a, 52a, and 53a, which will be described in detail later, are formed on the third to fifth surfaces 11C to 11E of the first to sixth surfaces 11A to 11F.

[0020] More specifically, a pump port 31a is formed in the third surface 11C of the valve block 11, and a pump port 32a is formed in the fourth surface 11D. Hydraulic pumps 8 and 9 are connected to the pump ports 31a and 32a, respectively (see also FIG. 2). Connection ports 41a, 43a, 45a, 49a, and 50a are further formed in the third surface 11C of the valve block 11, and connection ports 41b, 45b, 52a, and 53a are formed in the fourth surface 11D. Two tank ports 33a and 33b and four connection ports 35a, 36a, 38a, and 39a are further formed in the fifth surface 11E of the valve block 11. Tank port 33a is connected to tank 30 (see FIG. 2). As will be described in detail later, the connection ports 35a, 36a, 38a, 39a, 41a, 41b, 43a, 45a, 45b, 47a, 49a, 50a, 52a, and 53a are connected to the ports 2a to 7a and 2b to 7b of the actuators 2 to 7. Furthermore, the valve block 11 has various passages 31 to 54, which will be described in detail later.

[0021] 5 and 6 control the flow of hydraulic fluid to each of the actuators 2 to 7. Each of the spools 12 to 25, which will be described in more detail, is associated with each of the actuators 2 to 7 and controls the flow of hydraulic fluid supplied to and discharged from the corresponding actuator 2 to 7. In this embodiment, the spools 12 to 24 include a first traveling spool 12, a second traveling spool 13, a first boom head side spool 14, a second boom head side spool 15, a boom rod side spool 16, a first arm head side spool 17, a second arm head side spool 18, a first arm rod side spool 19, a second arm rod side spool 20, a bucket head side spool 21, a bucket rod side spool 22, a first swing spool 23, and a second swing spool 24. The spools 12 to 24 are inserted into the valve block 11 so as to be slidable in the height direction. The spools 12 to 24 control the flow of hydraulic fluid by stroking. In addition to the spools 12 to 24, a confluence spool 25 is also inserted into the valve block 11 so as to be slidable in the height direction.

[0022] As shown in Figures 4 and 7, the multi-control valve 10 also includes a plurality of solenoid valves 12a to 24a and 12b to 25b. Each of the solenoid valves 12a to 24a and 12b to 25b is provided in the valve block 11 in correspondence with a corresponding one of the spools 12 to 25 (see also Figures 5 and 6, for example). Each of the solenoid valves 12a to 24a and 12b to 25b outputs a pilot pressure to the corresponding spool 12 to 25 in response to an input signal. This causes each of the solenoid valves 12a to 24a and 12b to 25b to stroke the corresponding spool 12 to 25. The multi-control valve 10 configured in this manner has a hydraulic circuit 10a as follows:

[0023] <Hydraulic Circuit in Multi-Control Valve> The hydraulic circuit 10a in the multi-control valve 10 will be described below with reference to FIG. 3. The valve block 11 has two main passages 31, 32 and a tank passage 33. Each main passage 31, 32 has a pump port 31a, 32a. The first main passage 31 is connected to the first hydraulic pump 8 via the first pump port 31a, and the second main passage 32 is connected to the second hydraulic pump 9 via the second pump port 32a. The first main passage 31 is connected to the spools 12, 14, 16, 18, 20, 21, and 22 in parallel. The second main passage 32 is connected to the spools 13, 15, 17, 19, 23, and 24 in parallel. The tank passage 33 is connected to the tank 30 via tank ports 33a and 33b (see FIG. 4). Each of the spools 12 to 25 will be described in more detail below.

[0024] [Travel Spool] As described above, the first travel spool 12 is connected to the first hydraulic pump 8. More specifically, the first travel spool 12 is connected to the first main passage 31 via the first travel passage 34, in which the check valve 34a is located, and is further connected to the first hydraulic pump 8 via the first main passage 31. The first travel spool 12 is also connected to the tank passage 33. The first travel spool 12 controls the flow of hydraulic fluid supplied to and discharged from the first travel motor 2. More specifically, the first travel motor 2 has a first supply / discharge port 2a and a second supply / discharge port 2b. The first travel spool 12 is connected to the first supply / discharge port 2a via the first supply / discharge passage 35, and to the second supply / discharge port 2b via the second supply / discharge passage 36. The first traveling spool 12 receives pilot pressures output from the solenoid valves 12a, 12b in opposing directions and strokes to a position corresponding to the pilot pressures of the solenoid valves 12a, 12b. By stroking, the first traveling spool 12 switches the connection destinations of the supply / discharge ports 2a, 2b to the first main passage 31 and the tank passage 33, respectively, and adjusts the opening degree of the first traveling spool 12. In this way, the first traveling spool 12 controls the flow of hydraulic fluid to the first supply / discharge port 2a and the second supply / discharge port 2b of the first traveling motor 2.

[0025] As described above, the second traveling spool 13 is connected to the second hydraulic pump 9. More specifically, the second traveling spool 13 is connected to the second main passage 32 via the second traveling passage 37, in which the check valve 37a is located, and is further connected to the second hydraulic pump 9 via the second main passage 32. The second traveling spool 13 is also connected to the tank passage 33. The second traveling spool 13 controls the flow of hydraulic fluid supplied to and discharged from the second traveling motor 3. More specifically, the second traveling motor 3 has a first supply / discharge port 3a and a second supply / discharge port 3b. The second traveling spool 13 is connected to the first supply / discharge port 3a via the first supply / discharge passage 38, and to the second supply / discharge port 3b via the second supply / discharge passage 39. The second traveling spool 13 receives pilot pressures output from the solenoid valves 13a, 13b in opposing directions and strokes to a position corresponding to the pilot pressures of the solenoid valves 13a, 13b. By stroking, the second traveling spool 13 switches the connection destinations of the supply / discharge ports 3a, 3b to the second main passage 32 and the tank passage 33, respectively, and adjusts the opening degree of the second traveling spool 13. In this way, the second traveling spool 13 controls the flow of hydraulic fluid to the first supply / discharge port 3a and the second supply / discharge port 3b of the second traveling motor 3.

[0026] [Boom Spool] As described above, the first boom head-side spool 14 is connected to the first hydraulic pump 8. More specifically, the first boom head-side spool 14 is connected to the first main passage 31 via the first boom passage 40 in which the check valve 40a is disposed, and is further connected to the first hydraulic pump 8 via the first main passage 31. The first boom head-side spool 14 is also connected to the tank 30 via a tank passage 33. The first boom head-side spool 14 controls the flow of hydraulic fluid to the head-side port 5a of the boom cylinder 5. The boom cylinder 5 has two ports 5a, 5b, and the head-side port 5a is, for example, one port 5a of the two ports 5a, 5b. More specifically, the first boom head-side spool 14 is connected to the head-side port 5a via a head-side passage 41. The first boom head-side spool 14 receives pilot pressures output from the solenoid valves 14a, 14b in opposing directions and strokes to a position corresponding to the pilot pressures of the solenoid valves 14a, 14b. By stroking, the first boom head-side spool 14 switches the connection of the head-side port 5a between the first main passage 31 and the tank passage 33. This allows the first boom head-side spool 14 to supply hydraulic fluid from the first hydraulic pump 8 to the head-side port 5a of the boom cylinder 5, or to discharge hydraulic fluid from the head-side port 5a of the boom cylinder 5 to the tank 30. The first boom head-side spool 14 also adjusts its opening. This allows the first boom head-side spool 14 to control the flow rate of hydraulic fluid supplied to or discharged from the head-side port 5a of the boom cylinder 5.

[0027] As described above, the second boom head side spool 15 is connected to the second hydraulic pump 9. More specifically, the second boom head side spool 15 is connected to the second main passage 32 via the second boom passage 42 in which the check valve 42a is located, and is connected to the second hydraulic pump 9 via the second main passage 32. The second boom head side spool 15 is also connected to the tank 30 via the tank passage 33. The second boom head side spool 15 controls the flow of hydraulic fluid to the head side port 5a of the boom cylinder 5. More specifically, the second boom head side spool 15 is connected in parallel to the first boom head side spool 14 via the head side passage 41. The second boom head side spool 15 is also connected to the head side port 5a via the head side passage 41. The second boom head-side spool 15 receives pilot pressures output from the solenoid valves 15a, 15b in opposing directions and strokes to a position corresponding to the pilot pressures of the solenoid valves 15a, 15b. By stroking, the second boom head-side spool 15 switches the connection destination of the head-side port 5a between the second main passage 32 and the tank passage 33, and adjusts the aperture of the second boom head-side spool 15. This allows the second boom head-side spool 15 to supply hydraulic fluid from the second hydraulic pump 9 to the head-side port 5a of the boom cylinder 5, or to discharge hydraulic fluid from the head-side port 5a of the boom cylinder 5 to the tank 30. The second boom head-side spool 15 also adjusts its aperture. This allows the second boom head-side spool 15 to control the flow rate of hydraulic fluid supplied to or discharged from the head-side port 5a of the boom cylinder 5.

[0028] As described above, the boom rod side spool 16 is connected to the first hydraulic pump 8. Explaining in more detail, the boom rod side spool 16 is connected to the first main passage 31 via the first boom passage 40, and is further connected to the first hydraulic pump 8 via the first main passage 31. Explaining in even more detail, the boom rod side spool 16 is connected to the downstream side of the check valve 40a so as to be in parallel with the first boom head side spool 14, and is connected to the first main passage 31 together with the first boom head side spool 14 via the check valve 40a. The boom rod side spool 16 is also connected to the tank 30 via the tank passage 33. The boom rod side spool 16 controls the flow of hydraulic fluid to the rod side port 5b, which is the other port 5b of the boom cylinder 5. Explaining in more detail, the boom rod side spool 16 is connected to the rod side port 5b via the rod side passage 43. The boom rod-side spool 16 receives pilot pressures output from the solenoid valves 16a, 16b in opposing directions, and strokes to a position corresponding to the pilot pressures of the solenoid valves 16a, 16b. By stroking, the boom rod-side spool 16 switches the connection destination of the rod-side port 5b to either the first main passage 31 or the tank passage 33. This allows the boom rod-side spool 16 to supply hydraulic fluid from the first hydraulic pump 8 to the rod-side port 5b of the boom cylinder 5, or to discharge hydraulic fluid from the rod-side port 5b of the boom cylinder 5 to the tank 30. The boom rod-side spool 16 also adjusts its opening. This allows the boom rod-side spool 16 to control the flow rate of hydraulic fluid supplied to or discharged from the rod-side port 5b of the boom cylinder 5.

[0029] The spools 14 to 16 configured in this manner stroke independently of one another. Therefore, the spools 14 to 16 can independently control the flow of hydraulic fluid supplied to and discharged from the head-side port 5a and the rod-side port 5b of the boom cylinder 5. That is, the spools 14 to 16 can independently control the meter-in flow rate and the meter-out flow rate for each of the head-side port 5a and the rod-side port 5b of the boom cylinder 5. Furthermore, by stroking both of the boom head-side spools 14, 15, hydraulic fluid from the second hydraulic pump 9 can be supplied to the head-side port 5a of the boom cylinder 5 in addition to hydraulic fluid from the first hydraulic pump 8. Therefore, by stroking both of the spools 14, 15, a greater flow rate can be supplied to the head-side port 5a of the boom cylinder 5 than when only one spool 14 is stroked.

[0030] [Arm Spool] The first arm head-side spool 17 is connected to the second hydraulic pump 9. More specifically, the first arm head-side spool 17 is connected to the second main passage 32 via a first arm passage 44 having a check valve 44a interposed therein, and is further connected to the second hydraulic pump 9 via the second main passage 32. The first arm head-side spool 17 is also connected to the tank 30 via a tank passage 33. The first arm head-side spool 17 controls the flow of hydraulic fluid supplied to and discharged from the head-side port 6a of the arm cylinder 6. The arm cylinder 6 has two ports 6a, 6b, and the head-side port 6a is one of the two ports 6a, 6b. More specifically, the first arm head-side spool 17 is connected to the head-side port 6a via a head-side passage 45. The first arm head-side spool 17 receives pilot pressures output from the solenoid valves 17a, 17b in opposing directions, and strokes to a position corresponding to the pilot pressures of the solenoid valves 17a, 17b. By stroking, the first arm head-side spool 17 switches the connection destination of the head-side port 6a to either the second main passage 32 or the tank passage 33. This allows the first arm head-side spool 17 to supply hydraulic fluid from the second hydraulic pump 9 to the head-side port 6a of the arm cylinder 6, or to discharge hydraulic fluid from the head-side port 6a of the arm cylinder 6 to the tank 30. The first arm head-side spool 17 also adjusts its opening. This allows the first arm head-side spool 17 to control the flow rate of hydraulic fluid supplied to or discharged from the head-side port 6a of the arm cylinder 6.

[0031] As described above, the second arm head-side spool 18 is connected to the first hydraulic pump 8. More specifically, the second arm head-side spool 18 is connected to the first main passage 31 via the second arm passage 46 in which the check valve 46a is disposed, and is further connected to the first hydraulic pump 8 via the first main passage 31. The second arm head-side spool 18 is also connected to the tank 30 via the tank passage 33. The second arm head-side spool 18 controls the flow of hydraulic fluid to the head-side port 6a of the arm cylinder 6. More specifically, the second arm head-side spool 18 is connected in parallel to the first arm head-side spool 17 via the head-side passage 45. The second arm head-side spool 18 is also connected to the head-side port 6a via the head-side passage 45. The second arm head-side spool 18 receives pilot pressures output from the solenoid valves 18a, 18b in opposing directions, and strokes to a position corresponding to the pilot pressures of the solenoid valves 18a, 18b. By stroking, the second arm head-side spool 18 switches the connection of the head-side port 6a to either the first main passage 31 or the tank passage 33. This allows the second arm head-side spool 18 to supply hydraulic fluid from the first hydraulic pump 8 to the head-side port 6a of the arm cylinder 6, or to discharge hydraulic fluid from the head-side port 6a of the arm cylinder 6 to the tank 30. The second arm head-side spool 18 also adjusts its opening. This controls the flow rate of hydraulic fluid supplied to or discharged from the head-side port 6a of the arm cylinder 6.

[0032] As described above, the first arm rod side spool 19 is connected to the second hydraulic pump 9. More specifically, the first arm rod side spool 19 is connected to the second main passage 32 via the first arm passage 44, and further connected to the second hydraulic pump 9 via the second main passage 32. More specifically, the first arm rod side spool 19 is connected to the downstream side of the check valve 44a in the first arm passage 44 so as to be parallel to the first arm head side spool 17, and is connected to the second main passage 32 together with the first arm head side spool 17 via the check valve 44a. The first arm rod side spool 19 is also connected to the tank 30 via a tank passage 33. The first arm rod side spool 19 controls the flow of hydraulic fluid to the rod side port 6b, which is the other port 6b of the arm cylinder 6. More specifically, the first arm rod side spool 19 is connected to the rod side port 6b via a rod side passage 47. The first arm rod-side spool 19 receives pilot pressures output from the solenoid valves 19a, 19b in opposing directions, and strokes to a position corresponding to the pilot pressures of the solenoid valves 19a, 19b. By stroking, the first arm rod-side spool 19 switches the connection destination of the rod-side port 6b to either the second main passage 32 or the tank passage 33. This allows the first arm rod-side spool 19 to supply hydraulic fluid from the second hydraulic pump 9 to the rod-side port 6b of the arm cylinder 6, or to discharge hydraulic fluid from the rod-side port 6b of the arm cylinder 6 to the tank 30. The first arm rod-side spool 19 also adjusts its opening. This allows the first arm rod-side spool 19 to control the flow of hydraulic fluid supplied to or discharged from the rod-side port 6b of the arm cylinder 6.

[0033] As described above, the second arm rod side spool 20 is connected to the first hydraulic pump 8. Explaining in more detail, the second arm rod side spool 20 is connected to the first main passage 31 via the second arm passage 46, and further connected to the first hydraulic pump 8 via the first main passage 31. Explaining in even more detail, the second arm rod side spool 20 is connected to the downstream side of the check valve 46a in the second arm passage 46 so as to be parallel to the second arm head side spool 18, and is connected to the first main passage 31 together with the second arm head side spool 18 via the check valve 46a. The second arm rod side spool 20 is also connected to the tank 30 via the tank passage 33. Furthermore, the second arm rod side spool 20 controls the flow of hydraulic fluid to the rod side port 6b of the arm cylinder 6. Explaining in even more detail, the second arm rod side spool 20 is connected to the rod side passage 47 so as to be parallel to the first arm rod side spool 19. The second arm rod-side spool 20 is connected to the rod-side port 6b via a rod-side passage 47. The second arm rod-side spool 20 receives pilot pressures output from the solenoid valves 20a, 20b in opposing directions and strokes to a position corresponding to the pilot pressures of the solenoid valves 20a, 20b. By stroking, the second arm rod-side spool 20 switches the connection of the rod-side port 6b to either the first main passage 31 or the tank passage 33. This allows the second arm rod-side spool 20 to supply hydraulic fluid from the first hydraulic pump 8 to the rod-side port 6b of the arm cylinder 6 and to discharge hydraulic fluid from the rod-side port 6b of the arm cylinder 6 to the tank 30. The second arm rod-side spool 20 also adjusts its opening. This allows the second arm rod-side spool 20 to control the flow of hydraulic fluid supplied to and discharged from the rod-side port 6b of the arm cylinder 6.

[0034] The spools 17-20 configured in this manner stroke independently of each other. Therefore, the spools 17-20 can independently control the flow of hydraulic fluid supplied to and discharged from the head side port 6a and the rod side port 6b of the arm cylinder 6. That is, the spools 17-20 can independently control the meter-in flow rate and the meter-out flow rate for each of the head side port 6a and the rod side port 6b of the arm cylinder 6. Furthermore, by stroking both of the arm head side spools 17, 18, hydraulic fluid from the first hydraulic pump 8 can be supplied to the head side port 6a in addition to hydraulic fluid from the second hydraulic pump 9. Therefore, the arm head side spools 17, 18 can supply a larger flow rate to the head side port 6a of the arm cylinder 6 than when only one spool 17 is stroked. The same applies to the arm rod side spools 20, 19.

[0035] [Bucket Spool] As described above, the bucket head-side spool 21 is connected to the first hydraulic pump 8. Explaining in more detail, the bucket head-side spool 21 is connected to the first main passage 31 via a bucket passage 48 in which a check valve 48a is disposed, and is further connected to the first hydraulic pump 8 via the first main passage 31. The bucket head-side spool 21 is also connected to the tank 30 via a tank passage 33. The bucket head-side spool 21 controls the flow of hydraulic fluid to the head-side port 7a of the bucket cylinder 7. The bucket cylinder 7 has two ports 7a, 7b, and the head-side port 7a is one of the two ports 7a, 7b. Explaining in more detail, the bucket head-side spool 21 is connected to the head-side port 7a via a head-side passage 49. The bucket head-side spool 21 receives pilot pressures output from the solenoid valves 21a, 21b in opposing directions, and strokes to a position corresponding to the pilot pressures of the solenoid valves 21a, 21b. By stroking, the bucket head-side spool 21 switches the connection destination of the head-side port 7a to either the first main passage 31 or the tank passage 33. This allows the bucket head-side spool 21 to supply hydraulic fluid from the first hydraulic pump 8 to the head-side port 7a of the bucket cylinder 7, or to discharge hydraulic fluid from the head-side port 7a of the bucket cylinder 7 to the tank 30. The bucket head-side spool 21 also adjusts its opening. This allows the bucket head-side spool 21 to control the flow rate of hydraulic fluid supplied to or discharged from the head-side port 7a of the bucket cylinder 7.

[0036] As described above, the bucket rod side spool 22 is connected to the first hydraulic pump 8. Explaining in more detail, the bucket rod side spool 22 is connected to the first main passage 31 via the bucket passage 48, and is further connected to the first hydraulic pump 8 via the first main passage 31. Explaining in even more detail, the bucket rod side spool 22 is connected in the bucket passage 48 to the downstream side of the check valve 48 a so as to be in parallel with the bucket head side spool 21, and is connected to the first main passage 31 together with the bucket head side spool 21 via the check valve 48 a. The bucket rod side spool 22 is also connected to the tank 30 via a tank passage 33. The bucket rod side spool 22 controls the flow of hydraulic fluid to the rod side port 7 b, which is the other port 7 b of the bucket cylinder 7. Explaining in more detail, the bucket rod side spool 22 is connected to the rod side port 7 b via a rod side passage 50. The bucket rod-side spool 22 receives pilot pressures output from the solenoid valves 22 a, 22 b in opposing directions, and strokes to a position corresponding to the pilot pressures of the solenoid valves 22 a, 22 b. By stroking, the bucket rod-side spool 22 switches the connection destination of the rod-side port 7 b to either the first main passage 31 or the tank passage 33. This allows the bucket rod-side spool 22 to supply hydraulic fluid from the first hydraulic pump 8 to the rod-side port 7 b of the bucket cylinder 7, or to discharge hydraulic fluid from the rod-side port 7 b of the bucket cylinder 7 to the tank 30. The bucket rod-side spool 22 also adjusts its opening. This allows the bucket rod-side spool 22 to control the flow of hydraulic fluid supplied to or discharged from the rod-side port 7 b of the bucket cylinder 7.

[0037] The spools 21, 22 also stroke independently of each other. Therefore, the spools 21, 22 can independently control the flow of hydraulic fluid supplied to and discharged from the head side port 7 a and the rod side port 7 b of the bucket cylinder 7. That is, the spools 21, 22 can independently control the meter-in flow rate and the meter-out flow rate for the head side port 7 a and the rod side port 7 b of the bucket cylinder 7, respectively.

[0038] [Swivel Spool] As described above, the first swing spool 23 is connected to the second hydraulic pump 9. More specifically, the first swing spool 23 is connected to the second main passage 32 via a swing passage 51 having a check valve 51a interposed therein, and is further connected to the second hydraulic pump 9 via the second main passage 32. The first swing spool 23 is also connected to the tank 30 via a tank passage 33. The first swing spool 23 controls the flow of hydraulic fluid to the first supply / discharge port 4a of the swing motor 4. The swing motor 4 has two ports 4a, 4b, and the first supply / discharge port 4a is one of the two ports 4a, 4b, i.e., port 4a. More specifically, the first swing spool 23 is connected to the first supply / discharge port 4a via a first supply / discharge passage 52. The first swing spool 23 receives pilot pressures output from the solenoid valves 23a, 23b in opposing directions and strokes to a position corresponding to the pilot pressures of the solenoid valves 23a, 23b. By stroking, the first swing spool 23 switches the connection of the first supply / discharge port 4a to either the second main passage 32 or the tank passage 33. This allows the first swing spool 23 to supply hydraulic fluid from the second hydraulic pump 9 to the first supply / discharge port 4a of the swing motor 4, or to discharge hydraulic fluid from the first supply / discharge port 4a of the swing motor 4 to the tank 30. The first swing spool 23 also adjusts its opening. This allows the first swing spool 23 to control the flow of hydraulic fluid supplied to or discharged from the first supply / discharge port 4a of the swing motor 4.

[0039] As described above, the second swing spool 24 is connected to the second hydraulic pump 9. More specifically, the second swing spool 24 is connected to the second main passage 32 via the swing passage 51, and further connected to the second hydraulic pump 9 via the second main passage 32. More specifically, the second swing spool 24 is connected in the swing passage 51 downstream of the check valve 51a in parallel with the first swing spool 23, and is connected to the second main passage 32 together with the second swing spool 24 via the check valve 51a. The second swing spool 24 is also connected to the tank 30 via the tank passage 33. The second swing spool 24 controls the flow of hydraulic fluid to the second supply / discharge port 4b, which is the other port 4b of the swing motor 4. More specifically, the second swing spool 24 is connected to the second supply / discharge port 4b via the second supply / discharge passage 53. The second swing spool 24 receives pilot pressures output from the solenoid valves 24a, 24b in opposing directions and strokes to a position corresponding to the pilot pressures of the solenoid valves 24a, 24b. By stroking, the second swing spool 24 switches the connection of the second supply / discharge port 4b to either the second main passage 32 or the tank passage 33. This allows the second swing spool 24 to supply hydraulic fluid from the second hydraulic pump 9 to the second supply / discharge port 4b of the swing motor 4, or to discharge hydraulic fluid from the second supply / discharge port 4b of the swing motor 4 to the tank 30. The second swing spool 24 also adjusts its opening. This allows the second swing spool 24 to control the flow of hydraulic fluid supplied to or discharged from the second supply / discharge port 4b of the swing motor 4.

[0040] The spools 23, 24 also stroke independently of each other. Therefore, the spools 23, 24 can independently control the flow of hydraulic fluid supplied to and discharged from the supply / discharge ports 4a, 4b of the swing motor 4. That is, the spools 23, 24 can independently control the meter-in flow rate and the meter-out flow rate for the supply / discharge ports 4a, 4b of the swing motor 4.

[0041] [Converging Spool] The converging spool 25 is disposed in a converging passage 54 connecting the two main passages 31, 32, and opens and closes the converging passage 54. The converging spool 25 receives pilot pressure output from the solenoid valve 25b in a direction against the biasing force of a spring mechanism 25d, which will be described in detail later, and strokes to a position corresponding to the pilot pressure of the solenoid valve 25b. The converging spool 25 opens and closes the converging passage 54 by stroking, and also adjusts the opening degree of the converging spool 25. In this way, the converging spool 25 merges the hydraulic fluid from the second main passage 32 to the first main passage 31 and in the opposite direction, and also controls the flow rate of the hydraulic fluid to be merged.

[0042] [Boom Regenerative Valve Body] The boom regenerative valve body 26 is connected to the head side passage 41 and the first arm passage 44. More specifically, the boom regenerative valve body 26 is connected to the head side passage 41 so as to be parallel to the spools 14, 15. The boom regenerative valve body 26 is also connected to the first arm passage 44 downstream of the check valve 44a so as to be parallel to the spools 17, 19. The boom regenerative valve body 26 regenerates hydraulic fluid discharged from the head side port 5a of the boom cylinder 5 to the arm cylinder 6. More specifically, the boom regenerative valve body 26 opens and closes in response to the pilot pressure output from the solenoid valve 26a, and adjusts the opening degree of the boom regenerative valve body 26. In this way, the boom regenerative valve body 26 regenerates hydraulic fluid from the head side port 5a of the boom cylinder 5 to the head side port 6a or the rod side port 6b of the arm cylinder 6, and controls the regenerated flow rate.

[0043] <Specific Configuration of Multi-Control Valve> The specific configuration of the multi-control valve 10 will be described below. As shown in FIGS. 5 and 6, the multi-control valve 10 includes a valve block 11 and multiple spools 12-25, as described above. Furthermore, as shown in FIGS. 8 to 11, the multi-control valve 10 includes multiple spool covers 12c-25c, multiple spring mechanisms 12d-25d, and multiple solenoid valves 12a-24a, 12b-25b. The valve block 11 is formed, for example, in a substantially rectangular parallelepiped shape, as shown in FIGS. 4 and 7. The valve block 11 includes a block main body 11a, multiple first spool holes 11b, and multiple second spool holes 11c.

[0044] The block body 11a is formed, for example, in a roughly rectangular parallelepiped shape and has the first to sixth surfaces 11A to 11F described above. In this embodiment, the block body 11a includes a first block member 11d and a second block member 11e. The first block member 11d constitutes one depth-wise side of the block body 11a (e.g., the rear portion), and the second block member 11e constitutes the other depth-wise side of the block body 11a (e.g., the front portion). The block body 11a can be divided into the first block member 11d and the second block member 11e in the depth direction. However, the block body 11a does not necessarily have to be divisible into the first block member 11d and the second block member 11e. The block body 11a has a plurality of first spool holes 11b and a plurality of second spool holes 11c formed as follows.

[0045] As shown in FIG. 5 , the first surface 11A of the block body 11a is formed with a plurality of first spool holes 11b. More specifically, the first surface 11A of the block body 11a has two rows of first spool holes 11b. In this embodiment, the first surface 11A of the block body 11a has, for example, six first spool holes 11b. The six first spool holes 11b are arranged in two rows in the width direction. Each row has three first spool holes 11b arranged in the depth direction. In each row, the first spool holes 11b are aligned in a row in the depth direction. In this embodiment, two first spool holes 11b are formed in the first block member 11d and four in the second block member 11e. Furthermore, the six first spool holes 11b extend in the height direction from the first surface 11A of the block body 11a.

[0046] As shown in FIG. 6 , the second spool holes 11c are formed on the second surface 11B of the block body 11a. More specifically, the second spool holes 11c are arranged in two rows on the second surface 11B of the block body 11a. In this embodiment, eight second spool holes 11c are formed on the second surface 11B of the block body 11a. The eight second spool holes 11c are arranged in two rows in the width direction and four rows in the depth direction. In each row, the second spool holes 11c are aligned in a row in the depth direction. In this embodiment, four second spool holes 11c are formed in each of the block members 11d and 11e. The eight second spool holes 11c extend in the height direction from the second surface 11B of the block body 11a.

[0047] Of the eight second spool holes 11c, six are arranged to correspond to the first spool holes 11b and extend toward the corresponding first spool holes 11b. A pair of spool holes 11b, 11c, which are the first spool hole 11b and the second spool hole 11c corresponding to each other, are arranged in a line in the vertical direction. In this embodiment, the pair of spool holes 11b, 11c are aligned in a line in the vertical direction so that their axes coincide with each other. A partition wall 11f is formed between the pair of spool holes 11b, 11c in the valve block 11 to separate them. The pair of spool holes 11b, 11c does not necessarily have to be aligned in a line.

[0048] The spools 12 to 25 are inserted into the valve block 11 as follows. That is, as shown in FIGS. 8 to 11, each of the spools 12 to 25 is slidably inserted into the first spool bore 11b and the second spool bore 11c of the valve block 11. In this embodiment, each of the spools 16, 19, 20, 22, 24, and 25 is slidably inserted into the first spool bore 11b. Each of the spools 16, 19, 20, 22, and 24 forms an inner pilot chamber 16e, 19e, 20e, 22e, and 24e between itself and the partition wall 11f in the first spool bore 11b. The remaining spools 12 to 15, 17, 18, 21, and 23 are slidably inserted into the second spool bore 11c. Each of the spools 12 and 13 defines an inner pilot chamber 12e, 13e at the bottom of the second spool bore 11c. Each of the spools 14, 15, 17, 18, 21, and 23 defines an inner pilot chamber 14e, 15e, 17e, 18e, 21e, and 23e between the spools and the partition wall 11f in the second spool bore 11c. Pilot pressure is introduced into each of the inner pilot chambers 12e to 24e, and each of the spools 12 to 24 receives the pilot pressure of the inner pilot chambers 12e to 24e in a direction away from the partition wall 11f (hereinafter referred to as "axially outward").

[0049] More specifically, the boom rod spool 16, the second arm rod spool 20, and the bucket rod spool 22 are slidably inserted into the first spool holes 11b in the row on one side in the width direction, in that order from the one side in the depth direction. The junction spool 25, the first arm rod spool 19, and the second swing spool 24 are slidably inserted into the first spool holes 11b in the row on the other side in the width direction, in that order from the one side in the depth direction. On the other hand, the first traveling spool 12, the first boom head spool 14, the second arm head spool 18, and the bucket head spool 21 are slidably inserted into the second spool holes 11c in the row on one side in the width direction, in that order from the one side in the depth direction. The second spool holes 11c in the row on the other side of the width direction are slidably inserted into the second traveling spool 13, the second boom head side spool 15, the first arm head side spool 17, and the first swivel spool 23, in that order from one side of the depth direction.

[0050] Explaining in more detail, the spools 14 to 25 are arranged in the valve block 11 as follows. That is, the first boom head side spool 14, which is an example of a first spool, and the boom rod side spool 16 are slidably provided in the valve block 11 in correspondence with the boom cylinder 5, which is an example of a first actuator. Explaining in more detail, the first boom head side spool 14 and the boom rod side spool 16 are slidably inserted into the corresponding first spool hole 11b and second spool hole 11c. Therefore, the boom rod side spool 16 and the first boom head side spool 14 are arranged in a row in the height direction so that their respective axes coincide.

[0051] Furthermore, a first-arm head-side spool 17 and a first-arm rod-side spool 19, which are examples of second spools, are slidably provided in the valve block 11 in correspondence with the arm cylinder 6, which is an example of a second actuator. More specifically, the first-arm head-side spool 17 and the first-arm rod-side spool 19 are slidably inserted into corresponding first and second spool holes 11b and 11c, respectively, which are different from the aforementioned spool holes 11b and 11c. As a result, the first-arm head-side spool 17 and the first-arm rod-side spool 19 are also aligned in the height direction so that their axes coincide. Furthermore, the second-arm head-side spool 18 and the second-arm rod-side spool 20 are also slidably inserted into corresponding first and second spool holes 11b and 11c, respectively. As a result, the second arm rod side spool 20 and the second arm head side spool 18 are also arranged in a line in the height direction so that their respective axes coincide.

[0052] In addition, the bucket head-side spool 21 and the bucket rod-side spool 22 are provided in the valve block 11 corresponding to the bucket cylinder 7, and are also arranged so that their axes coincide with each other. That is, the bucket head-side spool 21 and the bucket rod-side spool 22 are also slidably inserted into another corresponding first spool hole 11b and second spool hole 11c. The first swing spool 23 and the second swing spool 24 are provided in the valve block 11 corresponding to the swing motor 4, and are also arranged so that their axes coincide with each other. That is, the first swing spool 23 and the second swing spool 24 are also slidably inserted into another corresponding first spool hole 11b and second spool hole 11c.

[0053] The spool covers 12c to 25c are provided on the block body 11a so as to cover the openings of the respective spool holes 11b and 11c. That is, the spool covers 12c to 25c are provided on the block body 11a so as to cover the corresponding spools 12 to 25. More specifically, the first surface 11A of the block body 11a is provided with spool covers 16c, 19c, 20c, 24c, and 25c, respectively, and the second surface 11B of the block body 11a is provided with spool covers 12c to 15c, 17c, 18c, 21c, and 23c, respectively. In this embodiment, adjacent pairs of the spool covers 12c to 25c are integrally formed. However, adjacent pairs of the spool covers 12c to 25c do not necessarily have to be integrally formed. Additionally, outer pilot chambers 12f to 25f are formed within the spool covers 12c to 25c. The outer pilot chambers 12f to 25f correspond to the respective spools 12 to 25. Pilot pressure is introduced into the outer pilot chambers 12f to 25f, and the pilot pressure in each of the outer pilot chambers 12f to 24f acts on the corresponding spool 12 to 24 in a direction (hereinafter referred to as "axially inward") that resists the pilot pressure in the inner pilot chambers 12e to 24e.

[0054] The spring mechanisms 12d to 25d are housed in the spool covers 12c to 25c, respectively. In this embodiment, the spring mechanisms 12d to 25d are housed in the outer pilot chambers 12f to 25f, respectively. The spring mechanisms 12d to 25d correspond to the spools 12 to 25, and bias the corresponding spools 12 to 25. More specifically, the spring mechanisms 12d to 25d bias the spools 12 to 25 in the direction opposite to the stroke direction of the corresponding spools 12 to 25. This returns the spools 12 to 25 to their neutral positions.

[0055] The first solenoid valves 12a to 24a correspond to the spools 12 to 24, respectively. The first solenoid valves 12a to 24a output pilot pressures corresponding to signals input to the corresponding spools 12 to 24. In this embodiment, the first solenoid valves 12a to 24a are attached to the spool covers 12c to 24c of the corresponding spools 12 to 24, and are connected to the inner pilot chambers 12e to 24e, respectively. The first solenoid valves 12a to 24a output pilot pressures to the corresponding inner pilot chambers 12e to 24e.

[0056] The second solenoid valves 12b to 25b also correspond to the spools 12 to 25, respectively. The second solenoid valves 12b to 25b output pilot pressures according to signals input to the corresponding spools 12 to 25. In this embodiment, the second solenoid valves 12b to 25b are attached to the spool covers 12c to 25c of the corresponding spools 12 to 25, and are connected to the outer pilot chambers 12f to 25f, respectively. The second solenoid valves 12b to 25b output pilot pressures to the corresponding outer pilot chambers 12f to 25f.

[0057] The pilot pressures output from the first solenoid valves 12a to 24a and second solenoid valves 12b to 25b configured in this manner act in opposing directions on the corresponding spools 12 to 25. The biasing forces of the spring mechanisms 12d to 25d also act in opposing directions on the corresponding spools 12 to 25 against the biasing forces of the first solenoid valves 12a to 24a and second solenoid valves 12b to 25b. Therefore, each spool 12 to 25 strokes to a position where the biasing forces of the solenoid valves 12a to 24a, 12b to 25b and the spring mechanisms 12d to 25d balance out. As a result, each spool 12 to 25 controls the flow of hydraulic fluid in accordance with the signals input to the solenoid valves 12a to 24a, 12b to 25b.

[0058] The various passages 31-54 are formed in the block body 11a to realize the hydraulic circuit 10a described above. An example of the arrangement of the various passages 33-54 will be described below. Specifically, the first main passage 31 and the second main passage 32 are spaced apart on one and the other widthwise sides of the first spool hole 11b and the second spool hole 11c, as shown in FIG. 8 . The first main passage 31 and the second main passage 32 extend in the depth direction (see also FIGS. 9 to 11 ) and open to the third and fourth surfaces 11C and 11D, respectively, via pump ports 31a and 32a. The first traveling passage 34 and the second traveling passage 37 are adjacent to the first traveling spool 12 and the second traveling spool 13, respectively, and spaced apart on one and the other widthwise sides. The first traveling passage 34 is connected to the first main passage 31 and the first traveling spool 12, and the second traveling passage 37 is connected to the second main passage 32 and the second traveling spool 13. Furthermore, in the first traveling spool 12, first and second supply and discharge passages 35, 36 are connected to both axial sides of the first traveling passage 34, and the tank passage 33 is further connected to the axially outer sides of these. The first and second supply and discharge passages 35, 36 are connected to the first supply and discharge port 2a and the second supply and discharge port 2b, respectively, via first and second supply and discharge connection ports 35a, 36a that open on the fifth surface 11E of the valve block 11. Similarly, in the second traveling spool 13, first and second supply and discharge passages 38, 39 are connected to both axial sides of the second traveling passage 37, and the tank passage 33 is further connected to the axially outer sides of these. The first and second supply / discharge passages 38, 39 are connected to the first supply / discharge port 3a and the second supply / discharge port 3b, respectively, via first and second supply / discharge connection ports 38a, 39a that open on the fifth surface 11E of the valve block 11.

[0059] As shown in FIG. 9 , the first boom passage 40 and the second boom passage 42 are disposed apart from each other on one and the other side in the width direction. The first boom passage 40 is disposed adjacent to the first boom head side spool 14 and the boom rod side spool 16. The first boom passage 40 is connected to the first main passage 31 and branches off midway from the first main passage 31 to connect to the first boom head side spool 14 and the boom rod side spool 16. A check valve 40a is disposed in the first boom passage 40 at its branching point. The first boom head side spool 14 is connected in this order axially outward from the first boom passage 40 to the head side passage 41 and the tank passage 33. The boom rod side spool 16 is connected in this order axially outward from the first boom passage 40 to the rod side passage 43 and the tank passage 33. The rod-side passage 43 is connected to the rod-side port 5b of the boom cylinder 5 via a rod-side connection port 43a that opens on the third surface 11C. The head-side passage 41 extends to the fourth surface 11D, straddling the second boom head-side spool 15, and opens on the third and fourth surfaces 11C and 11D. The head-side passage 41 is connected to the head-side port 5a of the boom cylinder 5 via head-side connection ports 41a and 41b that open on the third and fourth surfaces 11C and 11D, respectively.

[0060] The second boom passage 42 is arranged adjacent to the second boom head side spool 15. The second boom passage 42 is connected to the second main passage 32 and the second boom head side spool 15 with a check valve 42a interposed therebetween. The second boom head side spool 15 is also connected to the head side passage 41 and the tank passage 33 axially outward of the second boom passage 42. Furthermore, the junction passage 54 is arranged adjacent to the other widthwise side of the junction spool 25. The junction passage 54 connects the first main passage 31 and the second main passage 32 with the junction spool 25 interposed therebetween.

[0061] As shown in FIG. 10 , the first arm passage 44 and the second arm passage 46 are disposed apart from each other on one and the other widthwise sides. The second arm passage 46 is disposed adjacent to the second arm head-side spool 18 and the second arm rod-side spool 20. The second arm passage 46 is connected to the first main passage 31 and branches off midway from the first main passage 31 to connect to the second arm head-side spool 18 and the second arm rod-side spool 20. A check valve 46a is disposed in the second arm passage 46 at its branching point. The head-side passage 45 and the tank passage 33 are connected to the second arm head-side spool 18, in that order, axially outward from the second arm passage 46. The rod-side passage 47 and the tank passage 33 are connected to the second arm rod-side spool 20, axially outward from the second arm passage 46. The head-side passage 45 extends in the width direction so as to straddle the two arm head-side spools 18, 17. The head-side passage 45 is connected to the head-side port 5a of the arm cylinder 6 via head-side connection ports 45a, 45b that open on the third and fourth surfaces 11C, 11D. The rod-side passage 43 extends in the other width direction so as to straddle the first arm rod-side spool 19. The rod-side passage 47 is connected to the rod-side port 5b of the arm cylinder 6 via a rod-side connection port 47a that opens on the fourth surface 11D.

[0062] The first arm passage 44 is disposed adjacent to the first arm head side spool 17 and the first arm rod side spool 19. The first arm passage 44 is connected to the second main passage 32, branches off from the second main passage 32 midway, and is connected to the first arm head side spool 17 and the first arm rod side spool 19. A check valve 44a is disposed in the first arm passage 44 at the branching point. A head side passage 45 and a tank passage 33 are connected in this order to the first arm head side spool 17 axially outward from the first arm passage 44. A rod side passage 47 and a tank passage 33 are connected in this order to the first arm rod side spool 19 axially outward from the first arm passage 44.

[0063] As shown in FIG. 11 , the bucket passage 48 and the swing passage 51 are arranged spaced apart on one and the other sides in the width direction. The bucket passage 48 is arranged adjacent to the bucket head-side spool 21 and the bucket rod-side spool 22. The bucket passage 48 is connected to the first main passage 31 and branches off midway from the first main passage 31 to connect to the bucket head-side spool 21 and the bucket rod-side spool 22. A check valve 48a is disposed in the bucket passage 48 at its branching point. A head-side passage 49 and a tank passage 33 are connected in this order to the bucket head-side spool 21 axially outward from the bucket passage 48. A rod-side passage 50 and a tank passage 33 are connected in this order to the bucket rod-side spool 22 axially outward from the bucket passage 48. The head-side passage 49 is connected to the head-side port 7a of the bucket cylinder 7 via a head-side connection port 49a that opens at the third surface 11C. The rod-side passage 50 is connected to the rod-side port 7b of the bucket cylinder 7 via a rod-side connection port 50a that opens in the third surface 11C.

[0064] The orbit passage 51 is disposed adjacent to the first orbit spool 23 and the second orbit spool 24. The orbit passage 51 is connected to the second main passage 32 and branches off from the second main passage 32 to connect to the first orbit spool 23 and the second orbit spool 24. A check valve 51a is disposed in the orbit passage 51 at its branching point. A first supply / discharge passage 52 and a tank passage 33 are connected to the first orbit spool 23 axially outward from the orbit passage 51. A second supply / discharge passage 53 and a tank passage 33 are connected to the second orbit spool 24 axially outward from the orbit passage 51. The first supply / discharge passage 52 is connected to the first supply / discharge port 4a of the orbit motor 4 via a first supply / discharge connection port 52a opening at the fourth surface 11D. The second supply / discharge passage 53 is connected to the second supply / discharge port 4b of the swing motor 4 via a second supply / discharge connection port 53a that opens on the fourth surface 11D.

[0065] <Arrangement of Ports in Multi-Control Valve> On each of faces 11C to 11E of valve block 11 of multi-control valve 10, ports 31a, 32a, 33a, 33b, 35a, 36a, 38a, 39a, 41a, 41b, 43a, 45a, 45b, 47a, 49a, 50a, 52a, and 53a are formed as follows: That is, on third face 11C, as shown in FIG. 7 , first pump port 31a, head-side connection port 41a and rod-side connection port 43a connected to boom cylinder 5, head-side connection port 45a connected to arm cylinder 6, and head-side connection port 49a and rod-side connection port 50a connected to bucket cylinder 7 are formed. More specifically, on the third surface 11C, the first pump port 31a, the head side connection port 41a, and the rod side connection port 43a are formed in the first block member 11d, and the head side connection port 45a, the head side connection port 49a, and the rod side connection port 50a are formed in the second block member 11e. In this embodiment, the pump port 31a and the connection ports 41a, 43a, 45a, 49a, and 50a are formed on the third surface 11C as follows.

[0066] That is, the first pump port 31a is disposed on one side in the depth direction of the other connection ports 41a, 43a, 45a, 49a, and 50a on the third surface 11C. The head side connection port 41a and the rod side connection port 43a are aligned in the height direction and disposed on the other side in the depth direction of the first pump port 31a. Furthermore, in this embodiment, the rod side connection port 43a and the head side connection port 41a are disposed apart on one side and the other side in the height direction so that the check valve 40a is located between them.

[0067] The head-side connection port 45a is disposed on the other side in the depth direction than the head-side connection port 41a and the rod-side connection port 43a. More specifically, the head-side connection port 45a is disposed closer to the other side in the depth direction, i.e., closer to the other side in the height direction, than the rod-side connection port 43a. Furthermore, the head-side connection port 49a and the rod-side connection port 50a are disposed on the other side in the depth direction than the head-side connection port 45a. Furthermore, in this embodiment, the rod-side connection port 50a and the head-side connection port 49a are disposed spaced apart on one side and the other side in the height direction so that the check valve 48a is located between them.

[0068] 4, the fourth surface 11D is formed with the second pump port 32a, the head-side connection port 41b connected to the boom cylinder 5, the head-side connection port 45b and the rod-side connection port 47a connected to the arm cylinder 6, and the first supply / discharge connection port 52a and the second supply / discharge connection port 53a connected to the swing motor 4. Explaining in more detail, on the fourth surface 11D, the second pump port 32a and the head-side connection port 41b are formed in the first block member 11d, and the head-side connection port 45b, the rod-side connection port 47a, the first supply / discharge connection port 52a, and the second supply / discharge connection port 53a are formed in the second block member 11e. Furthermore, in this embodiment, the pump port 32a and the connection ports 41b, 45b, 47a, 52a, and 53a are formed on the fourth surface 11D as follows.

[0069] That is, the second pump port 32a is disposed on one side of the other connection ports 41b, 45b, 47a, 52a, and 53a in the depth direction on the fourth surface 11D. The head-side connection port 41b is disposed on the other side of the second pump port 32a in the depth direction. More specifically, on the fourth surface 11D, a check valve 42a is disposed on the other side of the second pump port 32a in the depth direction, and the head-side connection port 41b is disposed on the other side of the check valve 42a in the height direction.

[0070] The head-side connection port 45b and the rod-side connection port 47a are aligned in the height direction and positioned on the other side of the head-side connection port 41b in the depth direction. More specifically, the rod-side connection port 47a is positioned on the other side of the head-side connection port 41b in the depth direction, i.e., closer to the other side in the height direction. On the other hand, the head-side connection port 45b is positioned away from the rod-side connection port 47a in one direction in the height direction so that the check valve 44a is located between the head-side connection port 45b and the rod-side connection port 47a. That is, the head-side connection port 45b is positioned closer to one side in the height direction. Furthermore, the first supply / exhaust connection port 52a and the second supply / exhaust connection port 53a are positioned in front of the head-side connection port 45b and the rod-side connection port 47a. In this embodiment, the second supply / exhaust connection port 53a and the first supply / exhaust connection port 52a are positioned away from one side in the height direction so that the check valve 51a is located between them.

[0071] 4, the fifth surface 11E is further formed with two tank ports 33a, 33b, first and second supply / discharge connection ports 35a, 36a connected to the first traveling motor 2, and first and second supply / discharge connection ports 38a, 39a connected to the second traveling motor 3. In this embodiment, the tank ports 33a, 33b and the connection ports 35a, 36a, 38a, 39a are formed on the fifth surface 11E as follows.

[0072] That is, the two tank ports 33a, 33b are arranged on the fifth surface 11E, closer to one side in the height direction. More specifically, the two tank ports 33a, 33b are arranged in the widthwise central portion so as to be aligned in the widthwise direction. On the other hand, the four connection ports 35a, 36a, 38a, 39a are arranged on the fifth surface 11E, closer to the other side in the height direction. Furthermore, the two pump ports 31a, 32a are arranged between the two tank ports 33a, 33b and the four connection ports 35a, 36a, 38a, 39a, which are spaced apart in the height direction, as viewed from one side in the depth direction. Furthermore, the four connection ports 35a, 36a, 38a, 39a are arranged in the widthwise central portion of the fifth surface 11E so as to be aligned in the widthwise direction. In this embodiment, the fifth surface 11E is formed with, in order from one widthwise side, first and second supply and discharge connection ports 35a, 36a connected to the first traveling motor 2, and first and second supply and discharge connection ports 38a, 39a connected to the second traveling motor 3. Note that the supply and discharge connection ports 35a, 36a, 38a, 39a do not necessarily have to be arranged in the order described above.

[0073] <Arrangement of multi-control valve in construction machine> In this embodiment, the components of the hydraulic drive system 100 are arranged as follows in the construction machine 1. That is, the two hydraulic pumps 8, 9, the drive source E, the multi-control valve 10, and the tank 30 are housed and arranged as follows within the revolving body 102 of the construction machine 1, as shown in FIG.

[0074] That is, within the revolving unit 102, a counterweight (not shown) is disposed at the rearmost position, and in front of that, the drive source E and the two hydraulic pumps 8, 9 are disposed side by side in the left-right direction (in a row in this embodiment). Explaining in more detail, the revolving unit 102 has a cabin 102a on its front left side, and the drive source E and the two hydraulic pumps 8, 9 are disposed between the cabin 102a and the counterweight in the fore-and-aft direction. Furthermore, a boom 103 is provided on the revolving unit 102 in a swingable manner at the front side, in the middle in the left-right direction.

[0075] The multi-control valves 10 are disposed behind the boom 103 so as to be adjacent to each other within the revolving unit 102. Explaining in more detail, the multi-control valves 10 are disposed within the revolving unit 102 so that their height, width, and depth directions correspond to the up-down, left-right, and front-to-rear directions, respectively, of the construction machine 1. In this manner, the first surface 11A and the second surface 11B of the multi-control valve 10 face in the up-down direction, the third and fourth surfaces 11C and 11D face in the right-hand and left-hand directions, respectively, and the fifth and sixth surfaces 11E and 11F face in the front-to-rear direction, respectively.

[0076] The tank 30 is disposed to the side of the multi-control valve 10 within the revolving unit 102. In this embodiment, the tank 30 is disposed on the right front side of the multi-control valve 10. More specifically, the tank 30 is disposed on the opposite side of the cabin 102a in the left-right direction, with the boom 103 in between.

[0077] 12, various pipes 61-64, 71-84 are provided on each of the surfaces 11C, 11D, and 11E of the multi-control valve 10. The first and second pump pipes 61, 62 are provided on the third and fourth surfaces 11C, 11D, respectively, and connected to the pump ports 31a, 32a. The first and second pump pipes 61, 62 extend from the third and fourth surfaces 11C, 11D, respectively, toward the first and second hydraulic pumps 8, 9, respectively, and are connected to the first and second hydraulic pumps 8, 9. The first and second tank pipes 63, 64 are provided on the fifth surface 11E, and connected to the tank ports 33a, 33b. The first and second tank pipes 63, 64 extend from the fifth surface 11E toward the tank 30, and are connected to the tank 30.

[0078] The actuator pipes 71 to 74 are provided on the fifth surface 11E and are connected to the supply and discharge connection ports 35a, 36a, 38a, and 39a, respectively. The actuator pipes 71 to 74 extend from the fifth surface 11E toward the travel motors 2 and 3 and are connected to the ports 2a, 2b, 3a, and 3b of the travel motors 2 and 3. More specifically, the actuator pipes 71 to 74 are arranged inside the travel device 101, passing from the fifth surface 11E through swivel joints (not shown) attached to the travel device 101, and are connected to the ports 2a, 2b, 3a, and 3b, respectively.

[0079] The other actuator pipes 75 to 84 are provided on the third and fourth surfaces 11C and 11D, respectively, and are connected to the connection ports 41a, 41b, 43a, 45a, 45b, 47a, 49a, 50a, 52a, and 53a. The actuator pipes 75 to 84 extend from the fifth surface 11E toward the actuators 4 to 7, and are connected to the ports 4a to 7a and 4b to 7b of the actuators 4 to 7.

[0080] In this way, in the multi-control valve 10, the pump ports 31a, 32a and the tank ports 33a, 33b are arranged rearward of the connection ports 41a, 41b, 43a, 45a, 45b, 47a, 49a, 50a, 52a, 53a connected to the actuators 4 to 7. Therefore, when laying out the pipes 61 to 64 and 75 to 84, it is possible to prevent the pipes 61 to 64 and 75 to 84 from interfering with each other, which makes it easier to arrange the pipes 61 to 64 and 75 to 84.

[0081] Furthermore, the supply and discharge connection ports 35a, 36a, 38a, and 39a are positioned on the other side of the fifth surface 11E in the height direction, i.e., toward the lower side of the construction machine 1, allowing the pipes 71 to 74 to be positioned closer to the traveling device 101. This prevents the pipes 71 to 74 from interfering with the other pipes 61 to 64 and 75 to 84, simplifying the layout of the pipes 61 to 64 and 71 to 84. In this embodiment, the fifth surface 11E of the multi-control valve 10 is positioned near the pivot axis L1 and adjacent to the swivel joints that are positioned along the pivot axis L1. This further prevents the pipes 71 to 74 from interfering with the other pipes 61 to 64 and 75 to 84, further simplifying the layout of the pipes 61 to 64 and 71 to 84.

[0082] <Flow of Hydraulic Fluid in the Multi-Control Valve> In the construction machine 1, when driving each of the actuators 2 to 7, the hydraulic drive system 100 is controlled as follows. That is, when driving the traveling device 101, pilot pressure is output from at least one of the solenoid valves 12a, 12b, 13a, and 13b. For example, when pilot pressure is output from the first solenoid valves 12a and 13a, the pilot pressure is directed to the inner pilot chambers 12e and 13e, respectively, and the traveling spools 12 and 13 are actuated. As a result, hydraulic fluid is supplied from the hydraulic pump 8 to the first traveling motor 2 via the first traveling spool 12, and from the hydraulic pump 9 to the second traveling motor 3 via the second traveling spool 13. This drives the traveling device 101.

[0083] When the swing unit 102 is rotated, a pilot pressure is output from one of the solenoid valves 23a, 23b, 24a, and 24b. For example, when the pilot pressure is output from the solenoid valves 23a and 24b, the pilot pressure is introduced into the pilot chambers 23f and 24e, activating the swing motor 4. At this time, hydraulic fluid is supplied from the hydraulic pump 8 to the first supply / discharge port 4a via the first swing spool 23, and is then discharged from the second supply / discharge port 4b to the second swing spool 24 and into the tank 30. The first swing spool 23 and the second swing spool 24 can independently stroke, and their respective openings can be adjusted independently. Therefore, the multi-control valve 10 can independently control the flow rates of the fluid flowing through the first supply / discharge port 4a and the second supply / discharge port 4b, enabling more precise control of the swing motor 4.

[0084] Furthermore, when driving the boom 103, specifically when extending the boom cylinder 5, pilot pressure is output from the solenoid valves 14b and 16a. This pilot pressure is then directed to the pilot chambers 14f and 16e. As a result, hydraulic fluid from the first hydraulic pump 8 is directed to the head-side port 5a, and the boom cylinder 5 is extended. Furthermore, when a large flow rate is required through the head-side port 5a of the boom cylinder 5, pilot pressure is also output from the solenoid valve 15b. This pilot pressure is then directed to the pilot chamber 15f, and hydraulic fluid from the second hydraulic pump 9 is also directed to the head-side port 5a of the boom cylinder 5 via the second boom head-side spool 15. This allows a large flow rate through the head-side port 5a of the boom cylinder 5. On the other hand, when retracting the boom cylinder 5, pilot pressure is output from the solenoid valves 14a and 16b. This pilot pressure is then directed to the pilot chambers 14e and 16f, and the boom cylinder 5 is retracted.

[0085] In the boom cylinder 5 that extends and retracts in this manner, hydraulic fluid is supplied to and discharged from the head side port 5a via the boom head side spools 14, 15, and hydraulic fluid is supplied to and discharged from the rod side port 5b via the rod side spool 16. The spools 14 to 16 can stroke independently of one another, and their respective openings can be adjusted independently of one another. Therefore, with the multi-control valve 10, the flow rates supplied to and discharged from the head side port 5a and the rod side port 5b can also be controlled independently, allowing for more precise control of the boom cylinder 5.

[0086] Furthermore, when operating the arm 104, for example, when extending the arm cylinder 6, pilot pressure is output from the solenoid valves 17b and 19a. This pilot pressure is then guided to the pilot chambers 17f and 19e. As a result, hydraulic fluid from the second hydraulic pump 9 is guided to the head side port 6a, and the arm cylinder 6 is extended. Also, when a large flow rate is required through the head side port 6a of the arm cylinder 6, pilot pressure is also output from the solenoid valves 18b and 20a. This pilot pressure is then guided to the pilot chambers 18f and 20e, and hydraulic fluid from the first hydraulic pump 8 can also be guided to the head side port 6a of the arm cylinder 6 via the second arm head side spool 18. This allows a large flow rate of hydraulic fluid to flow through the head side port 6a of the arm cylinder 6. On the other hand, when retracting the arm cylinder 6, pilot pressure is output from the solenoid valves 17a and 19b. This pilot pressure is then guided to the pilot chambers 17e and 19f, and the arm cylinder 6 is retracted. Furthermore, by outputting pilot pressure from the solenoid valves 18 a and 20 b, a larger flow rate of hydraulic fluid can be made to flow to the rod side port 6 b of the arm cylinder 6 .

[0087] In the arm cylinder 6 that extends and retracts in this manner, hydraulic fluid is supplied to and discharged from the head side port 6a via the arm head side spools 17, 18, and from the rod side port 6b via the arm rod side spools 19, 20. Each spool 17-20 can stroke independently of the others, and their respective openings can be adjusted independently of each other. Therefore, with the multi-control valve 10, the flow rates supplied to and discharged from the head side port 6a and the rod side port 6b can also be controlled independently, allowing for more precise control of the arm cylinder 6.

[0088] Furthermore, when the bucket 105 is operated, for example, when the bucket cylinder 7 is extended, pilot pressure is output from the solenoid valves 21b and 22a. This leads to the pilot chambers 21f and 22e, and the bucket cylinder 7 is extended. On the other hand, when the bucket cylinder 7 is retracted, pilot pressure is output from the solenoid valves 21b and 22a. This leads to the pilot chambers 21e and 22f, and the bucket cylinder 7 is retracted.

[0089] Furthermore, when the arm 104 and the boom 103 are moved simultaneously and the boom 103 is retracted, pilot pressure is output from the solenoid valve 26 a. This allows the hydraulic fluid discharged from the head side port 5 a of the boom cylinder 5 to be regenerated in the arm cylinder 6 via the boom regeneration valve body 26.

[0090] In the multi-control valve 10 of the first embodiment, the first pump port 31a and the connection ports 41a and 43a for the boom cylinder 5 are formed on the third surface 11C, and the second pump port 32a and the connection ports 45b and 47a for the arm cylinder 6 are formed on the fourth surface 11D. Furthermore, the tank port 33a, the connection ports 35a and 36a for the first travel motor 2, and the connection ports 38a and 39a for the second travel motor 3 are formed on the fifth surface 11E. Therefore, the connection ports 35a, 36a, 38a, 39a, 41a, 43a, 45b, and 47a can be distributed across the third surface 11C, the fourth surface 11D, and the fifth surface 11E. This allows the valve block 11 to be miniaturized. That is, the layout of the ports 35a, 36a, 38a, 39a, 41a, 43a, 45b, and 47a allows the valve block 11 to be miniaturized.

[0091] Furthermore, in the multi-control valve 10 of the first embodiment, the first pump port 31a is formed on the third surface 11C on one side in the depth direction of the connection ports 41a and 43a of the boom cylinder 5, and the second pump port 32a is formed on the fourth surface 11D on one side in the depth direction of the connection ports 45b and 47a of the arm cylinder 6. Therefore, the tank port 33a and the two pump ports 31a and 32a can be arranged on one side in the depth direction, and the connection ports 41a, 43a, 45b, and 47a can be arranged on the other side in the depth direction. This makes it possible to prevent the layout of the pipes 61 to 64, 75, 77, 78, and 80 that connect the first and second hydraulic pumps 8 and 9, the tank 30, and the boom cylinder 5 and arm cylinder 6 to the multi-control valve 10 from becoming complicated.

[0092] Furthermore, in the multi-control valve 10 of the first embodiment, the fifth surface 11E has a tank port 33a formed on one side in the height direction, and connection ports 35a, 36a, 38a, and 39a formed on the other side in the height direction. Therefore, the layout of the pipes 63 and 64 connecting the multi-control valve 10 to the tank 30 and the pipes 71-74 connecting the multi-control valve 10 to the first and second travel motors 2 and 3 can be adjusted to prevent interference between them. For example, by positioning the multi-control valve 10 on the construction machine 1 so that the travel device 101 is located on the other side in the height direction, the pipes 71-74 are prevented from extending toward the pipes 63 and 64. Therefore, interference between the pipes 71-74 and the pipes 63 and 64 can be further prevented.

[0093] Furthermore, in the multi-control valve 10 of the first embodiment, the first pump port 31a is formed on the third surface 11C between the tank port 33a and the connection ports 35a, 36a, 38a, and 39a as viewed from one side in the depth direction, and on one side in the depth direction of the connection ports 41a and 43a of the boom cylinder 5. The second pump port 32a is formed on the fourth surface 11D between the tank port 33a and the connection ports 35a, 36a, 38a, and 39a as viewed from one side in the height direction, and on one side in the depth direction of the connection ports 45b and 47a of the arm cylinder 6. This allows the vertical positions of the pipes 61-64 and 71-74 connecting the tank 30, the first and second hydraulic pumps 8 and 9, and the first and second travel motors 2 and 3 to the multi-control valve 10 to be shifted. This further reduces interference between the pipes 61-64 and 71-74 when viewed from one side in the height direction.

[0094] Furthermore, in the multi-control valve 10 of the first embodiment, the connection ports 35a, 36a, 38a, and 39a are arranged side by side in the width direction, which allows the valve block 11 to be made compact in height.

[0095] Furthermore, in the multi-control valve 10 of the first embodiment, the first boom head side spool 14 and the boom rod side spool 16 are arranged so that their axes coincide, and the first arm head side spool 17 and the first arm rod side spool 19 are also arranged so that their axes coincide. That is, the first boom head side spool 14 and the boom rod side spool 16 are arranged in a line in the height direction, and the first arm head side spool 17 and the first arm rod side spool 19 are also arranged in a line in the height direction. This allows the valve block 11 to be made compact in the width and depth directions.

[0096] Furthermore, in the multi-control valve 10 of the first embodiment, the connection ports 41a, 43a of the boom cylinder 5 are ports connected to the boom cylinder 5, and the connection ports 45b, 47a of the arm cylinder 6 are ports connected to the arm cylinder 6. Furthermore, the third surface 11C is further formed with connection ports 49a, 50a connected to the bucket cylinder 7, and the fourth surface 11D is formed with connection ports 52a, 53a connected to the swing motor 4. Therefore, the multi-control valve 10 can control the flow of hydraulic fluid to each of the actuators 4 to 7 of the construction machine 1. Therefore, it is possible to provide a multi-control valve 10 that can be mounted on the construction machine 1 and that can achieve a reduction in the size of the valve block 11 by the layout of the ports 35a, 36a, 38a, 39a, 41a, 43a, 45b, 47a, 49a, 50a, 52a, 53a.

[0097] Furthermore, in the multi-control valve 10 of the first embodiment, by arranging the first boom head side spool 14 and the boom rod side spool 16 in a row in the height direction, it is possible to compactly arrange the passages 40, 41, 43 related to the boom cylinder 5, and by arranging the first arm head side spool 17 and the first arm rod side spool 19 in a row in the height direction, it is possible to compactly arrange the passages 44, 45, 47 related to the arm cylinder 6. This also makes it possible to make the valve block 11 compact.

[0098] Furthermore, in the multi-control valve 10 of the first embodiment, the bucket head-side spool 21 is disposed adjacent to the first swing spool 23 in the width direction, and the bucket rod-side spool 22 is disposed adjacent to the second swing spool 24 in the width direction. Therefore, the four spools 21 to 24 are disposed on a single imaginary plane perpendicular to the depth direction, allowing the valve block 11 to be formed compactly.

[0099] Furthermore, the construction machine 1 of the first embodiment is provided with the above-mentioned multi-control valve 10. Therefore, the installation space for the multi-control valve 10 in the construction machine 1 can be reduced.

[0100] Furthermore, in the construction machine 1 of the first embodiment, the multi-control valve 10 is provided inside the revolving unit 102 so that the third and fourth surfaces 11C and 11D face rightward and leftward, respectively. This allows the pipes 75 to 77 connected to the connection ports 41a, 41b, and 43a to be arranged so as to extend forward from the third and fourth surfaces 11C and 11D, making it easier to lay out the pipes 75 to 77.

[0101] Furthermore, in the construction machine 1 of the first embodiment, the first and second hydraulic pumps 8, 9 are disposed rearward of the multi-control valve 10. Furthermore, a first pump port 31a is formed on the third surface 11C on one side in the depth direction of the connection ports 41a, 43a of the boom cylinder 5, and a second pump port 32a is formed on the fourth surface 11D on one side in the depth direction of the connection ports 45b, 47a of the arm cylinder 6. Furthermore, the multi-control valve 10 is disposed so that the fifth surface 11E faces rearward. Therefore, the first and second pump ports 31a, 32a can be disposed closer to the first and second hydraulic pumps 8, 9 than the connection ports 41a, 43a, 45b, 47a. This makes it possible to prevent the pipes 61, 62, 75, 77, 78, 80 from interfering with each other when laying out the pipes 61, 62 connecting the multi-control valve 10 to the first and second hydraulic pumps 8, 9 and the pipes 75, 77, 78, 80 connecting the multi-control valve 10 to the boom cylinder 5 and the arm cylinder 6, respectively, thereby facilitating the layout of the pipes 61, 62, 75, 77, 78, 80.

[0102] Furthermore, in the construction machine 1 of the first embodiment, the tank 30 is disposed to the side of the multi-control valve 10 on the revolving bed 102, and the multi-control valve 10 is disposed so that the fifth surface 11E faces rearward. Therefore, the tank port 33a and the tank 30 can be easily attached by extending the pipes 63, 64 laterally from the tank port 33a.

[0103] 13 and 14 is provided in the construction machine 1 in the same manner as the multi-control valve 10 of the first embodiment, and is similar in configuration to the multi-control valve 10 of the first embodiment. Therefore, the configuration of the multi-control valve 110 of the second embodiment will be mainly described in terms of differences from the multi-control valve 10 of the first embodiment, and the same components will be denoted by the same reference numerals and description thereof will be omitted.

[0104] The multi-control valve 110 includes a valve block 111 and multiple spools 12-25. As shown in FIGS. 13 and 14 , the first and second supply / discharge connection ports 35a and 136a connected to the first traveling motor 2 and the first and second supply / discharge connection ports 38a and 139a connected to the second traveling motor 3 are arranged in the valve block 111 as follows: The first supply / discharge connection ports 35a and 38a connected to the traveling motors 2 and 3, respectively, are arranged on the fifth surface 11E. The second supply / discharge connection port 136a connected to the first traveling motor 2 is arranged on the third surface 11C, and the second supply / discharge connection port 139a connected to the second traveling motor 3 is arranged on the fourth surface 11D. More specifically, the second supply / discharge connection port 136a is arranged on the third surface 11C on the other side of the pump port 31a in the height direction, i.e., on one side in the depth direction. The second supply / discharge connection port 139a is arranged on the fourth surface 11D on the other side in the height direction of the pump port 32a, that is, on one side in the depth direction.

[0105] In the multi-control valve 110 of the second embodiment configured in this manner, the first supply and discharge connection ports 35a, 38a connected to the motors 2, 3 are formed on the fifth surface 11E. In addition, the second supply and discharge connection port 36a connected to the first travel motor 2 is formed on the third surface 11C, and the second supply and discharge connection port 39a connected to the second travel motor 3 is formed on the fourth surface 11D. This prevents the pipes connected to the first supply and discharge connection ports 35a, 38a from interfering with the second supply and discharge connection ports 136a, 139a.

[0106] In the multi-control valve 110 of the second embodiment, the first and second supply / discharge connection ports 35a, 136a are ports connected to the first travel motor 2, and the first and second supply / discharge connection ports 38a, 139a are ports connected to the second travel motor 3. Therefore, the layout of the piping connecting the multi-control valve 110 to the tank 30 and the piping connecting the multi-control valve 110 to the first and second travel motors 2, 3 can be designed to prevent interference with each other.

[0107] In addition, the multi-control valve 110 of the second embodiment has the same functions and effects as the multi-control valve 10 of the first embodiment.

[0108] [Other Embodiments] In the multi-control valves 10, 110 of the first and second embodiments, the boom cylinder 5 is given as an example of the first actuator, but the first actuator may be the swing motor 4, the arm cylinder 6, and the bucket cylinder 7. Similarly, the arm cylinder 6 is given as an example of the second actuator, but the second actuator may be the swing motor 4, the boom cylinder 5, and the bucket cylinder 7. Furthermore, the multi-control valve 10 does not necessarily have to be provided in the construction machine 1, and may be provided in other industrial machines.

[0109] Furthermore, in the multi-control valves 10, 110 of the first and second embodiments, the spools 14 and 15 are connected only to the head side port 5a, but they may also be connected to the rod side port 5b to control the meter-in flow rate of the rod side port 5b. Similarly, the spool 16 may also be connected to the head side port 5a to control the meter-out flow rate of the head side port 5a. Furthermore, both the spools 17 and 18 may be connected to the rod side port 6b to control the meter-in flow rate of the rod side port 6b. Furthermore, the spools 19 and 20 may also be connected to the head side port 6a to control the meter-out flow rate of the head side port 6a.

[0110] The number of spool holes 11b, 11c in the multi-control valves 10, 110 in the first and second embodiments is not limited to the above-described number, and each may have five or fewer spool holes 11b, 11c, or eight or more spool holes. Furthermore, while the spools 14, 15 are inserted into the corresponding spool holes 11b, 11c, they may be inserted into two different first spool holes 11b or two different second spool holes 11c, or into staggered spool holes 11b, 11c. The same applies to the spools 17, 18, spools 19, 20, spools 21, 22, and spools 23, 24. Furthermore, the layout of each port 31a, 32a, 33a, 33b, 35a, 36a, 38a, 39a, 41a, 41b, 43a, 45a, 45b, 47a, 49a, 50a, 52a, and 53a is an example and is not limited to the above-mentioned layout.

[0111] <Exemplary Embodiment> A multi-control valve according to a first aspect is a multi-control valve connected to a first pump, a second pump, first to fourth actuators, and a tank, and controls a flow of hydraulic fluid to each of the first to fourth actuators, the multi-control valve including a valve block including a first pump port connected to the first pump, a second pump port connected to the second pump, first to fourth connection ports connected to each of the first to fourth actuators, and a tank port connected to the tank; and a valve block provided in the valve block so as to be slidable in a first direction, corresponding to each of the first to fourth actuators, and connected to the corresponding actuator, at least one of the first pump and the second pump, and the tank, and a plurality of spool covers provided on the valve block so as to cover each of the plurality of spools, wherein the valve block includes a first surface and a second surface on one side and the other side in the first direction, a third surface and a fourth surface on one side and the other side in a second direction intersecting the first direction, and a fifth surface on one side in a third direction intersecting the first and second directions, and the plurality of spool covers are provided on the first surface and the second surface, the first pump port and the first connection port are formed on the third surface, the second pump port and the second connection port are formed on the fourth surface, and the tank port and the third and fourth connection ports are formed on the fifth surface.

[0112] According to the above aspect, the first pump port and the first connection port are formed on the third surface, and the second pump port and the second connection port are formed on the fourth surface. Furthermore, the tank port and the third and fourth connection ports are formed on the fifth surface. Therefore, the ports connected to the actuators can be distributed and formed on the third to fifth surfaces. This allows the valve block to be made smaller. That is, the layout of each port can achieve a smaller valve block.

[0113] In a multi-control valve of a second aspect, in the multi-control valve of the first aspect, the first pump port is formed on the third surface on one side in the third direction of the first connection port, and the second pump port is formed on the fourth surface on one side in the third direction of the second connection port.

[0114] According to the above aspect, the third surface has a first pump port formed on one side in the third direction of the first connection port, and the fourth surface has a second pump port formed on one side in the third direction of the second connection port. Therefore, the tank port and the two pump ports can be arranged on one side in the third direction, and the first and second connection ports can be arranged on the other side in the third direction. This makes it possible to prevent the layout of piping connecting the tank, the first and second pumps, and the first and second actuators to the multi-control valve from becoming complicated.

[0115] In a multi-control valve of a third aspect, in the multi-control valve of the first or second aspect, the third connection port is a port connected to a first travel motor provided in a travel device of a construction machine, the fourth connection port is a port connected to a second travel motor provided in the travel device, and the fifth surface has the tank port formed on one side in the first direction and the third and fourth connection ports formed on the other side in the first direction.

[0116] According to the above aspect, the fifth surface has a tank port formed on one side in the first direction and third and fourth connection ports formed on the other side in the first direction. Therefore, the layout of the piping connecting the multi-control valve to the tank and the piping connecting the multi-control valve to the first and second travel motors can be prevented from interfering with each other. For example, by arranging the multi-control valve on the construction machine so that the travel device is located on the other side in the first direction, the piping connecting the multi-control valve to the first and second travel motors is prevented from extending toward the piping connecting the multi-control valve to the tank. Therefore, interference between the piping connecting the multi-control valve to the first and second travel motors and the piping connecting the multi-control valve to the tank can be further prevented.

[0117] In a multi-control valve of a fourth aspect, in the multi-control valve of the third aspect, the first pump port is formed on the third surface between the tank port and the third and fourth connection ports and on one side of the first connection port in the third direction, as viewed from one side in the third direction, and the second pump port is formed on the fourth surface between the tank port and the third and fourth connection ports and on one side of the second connection port in the third direction, as viewed from one side in the third direction.

[0118] According to the above aspect, the first pump port is formed on the third surface between the tank port and the third and fourth connection ports and on one side of the first connection port in the third direction, as viewed from one side in the third direction. The second pump port is formed on the fourth surface between the tank port and the third and fourth connection ports and on one side of the second connection port in the third direction, as viewed from one side in the third direction. Therefore, with regard to the layout of piping connecting the tank, the first and second pumps, and the third and fourth actuators to the multi-control valve, interference between them can be further suppressed.

[0119] In a multi-control valve of a fifth aspect, in the multi-control valve of the third or fourth aspect, the valve block includes two of the third connection ports and two of the fourth connection ports, and the two third connection ports and the two fourth connection ports are arranged side by side in the second direction.

[0120] According to the above aspect, the two third connection ports and the two fourth connection ports are arranged side by side in the second direction, which allows the valve block to be made compact in the first direction.

[0121] In a sixth aspect, in the multi-control valve of any one of the first to fifth aspects, the plurality of spools include two first spools provided in the valve block corresponding to the first actuator and two second spools provided in the valve block corresponding to the second actuator, and the two first spools are arranged so that their respective axes coincide, and the two second spools are arranged so that their respective axes coincide.

[0122] According to the above aspect, the two first spools are arranged so that their axes coincide, and the two second spools are arranged so that their axes coincide. That is, the two first spools are arranged in a line in the first direction, and the two second spools are also arranged in a line in the first direction. Therefore, the valve block can be made compact in the second and third directions.

[0123] In a seventh aspect, in the multi-control valve of any one of the first to sixth aspects, the valve block further includes a fifth connection port connected to a bucket cylinder of a construction machine and a sixth connection port connected to a swing motor of the construction machine, the first connection port is a port connected to a boom cylinder of the construction machine, the second connection port is a port connected to an arm cylinder of the construction machine, the fifth connection port is further formed on the third surface, and the sixth connection port is formed on the fourth surface.

[0124] According to the above aspect, the first connection port is a port for a boom cylinder, and the second connection port is a port for an arm cylinder. Furthermore, a bucket port is further formed on the third surface, and a swing port is formed on the fourth surface. Therefore, the multi-control valve can control the flow of hydraulic fluid to each actuator of the construction machine. Therefore, it is possible to provide a multi-control valve that can be mounted on a construction machine and that can achieve a compact valve block by arranging the ports appropriately.

[0125] In a multi-control valve of an eighth aspect, in the multi-control valve of the seventh aspect, the plurality of spools include two boom spools provided in the valve block corresponding to the boom cylinders, and two arm spools provided in the valve block corresponding to the arm cylinders, and the two boom spools are arranged so that their axes coincide with each other, and the two arm spools are arranged so that their axes coincide with each other.

[0126] According to the above aspect, the two boom spools are arranged so that their axes coincide, and the two arm spools are arranged so that their axes coincide. That is, the two boom spools are arranged in a line in the first direction, and the two arm spools are also arranged in a line in the first direction. Therefore, the valve block can be made compact in the second and third directions. Furthermore, by arranging the two boom spools in a line in the first direction, the passages related to the boom cylinder can be arranged compactly, and by arranging the two arm spools in a line in the first direction, the passages related to the arm cylinder can be arranged compactly. This also makes it possible to make the valve block compact.

[0127] A multi-control valve in a ninth aspect is the multi-control valve of the seventh or eighth aspect, wherein the plurality of spools include two bucket spools provided in the valve block corresponding to the bucket cylinders and two swing spools provided in the valve block corresponding to the swing motors, the two bucket spools are arranged so that their respective axes coincide, the two swing spools are arranged so that their respective axes coincide, one of the two bucket spools is arranged so as to be adjacent to one of the two swing spools in the second direction, and the other of the two bucket spools is arranged so as to be adjacent to the other of the two swing spools in the second direction.

[0128] According to the above aspect, one bucket spool is disposed adjacent to one of the swing spools in the second direction, and the other bucket spool is disposed adjacent to the other swing spool in the second direction. Therefore, the two bucket spools and the two swing spools are disposed on a single imaginary plane perpendicular to the third direction, allowing the valve block to be formed compactly.

[0129] In a multi-control valve of a tenth aspect, in the multi-control valve of any of the first to fourth and sixth to ninth aspects, the valve block includes two of the third connection ports and two of the fourth connection ports, one of the two third connection ports is formed on the fifth surface, the other of the two third connection ports is formed on the third surface, one of the two fourth connection ports is formed on the fifth surface, and the other of the two fourth connection ports is formed on the fourth surface.

[0130] According to the above aspect, one of the two third connection ports is formed on the fifth surface, and the other of the two third connection ports is formed on the third surface. Also, one of the two fourth connection ports is formed on the fifth surface, and the other of the two fourth connection ports is formed on the fourth surface. Therefore, it is possible to prevent the pipes connected to the two third connection ports from interfering with each other. Similarly, it is possible to prevent the pipes connected to the two fourth connection ports from interfering with each other.

[0131] In an eleventh aspect of the multi-control valve, in the tenth aspect of the multi-control valve, the two third connection ports are ports connected to a first travel motor provided on a travel device of a construction machine, and the two fourth connection ports are ports connected to a second travel motor provided on the travel device.

[0132] According to the above aspect, the two third connection ports are ports connected to first travel motors provided on the travelling devices of the construction machine, and the two fourth connection ports are ports connected to second travel motors provided on the travelling devices. Therefore, it is possible to prevent interference between the piping connecting the multi-control valve and the tank, and the piping connecting the multi-control valve and the first and second travelling motors, respectively, in terms of layout.

[0133] A construction machine in a twelfth aspect includes a boom cylinder that drives a boom, an arm cylinder that drives an arm, a traveling device including first and second traveling motors, and a multi-control valve of any one of the first to eleventh aspects, wherein the first connection port is a port connected to the boom cylinder, the second connection port is a port connected to the arm cylinder, the third connection port is a port connected to the first traveling motor, and the fourth connection port is a port connected to the second traveling motor.

[0134] According to the above aspect, the construction machine is provided with the above-described multi-control valve, which makes it possible to reduce the installation space of the multi-control valve in the construction machine.

[0135] In a thirteenth aspect, the construction machine of the twelfth aspect further comprises a rotating body that is rotatably mounted on the traveling device, the boom cylinder is arranged on the front side of the rotating body so that it can swing up and down, and the multi-control valve is provided within the rotating body so that the third and fourth surfaces face in one and the other of the left and right directions, respectively.

[0136] According to the above aspect, the multi-control valve is provided in the rotating body so that the third and fourth faces face in the left and right directions, respectively. This allows the piping connected to the boom port to be arranged to extend forward from the third and fourth faces, making the piping layout easier.

[0137] In a fourteenth aspect, the construction machine is the construction machine of the thirteenth aspect, further comprising the first and second pumps arranged on the rotating body rearward of the multi-control valve, the first pump port being formed on the third surface on one side in the third direction from the first connection port, the second pump port being formed on the fourth surface on one side in the third direction from the second connection port, and the multi-control valve being arranged so that the fifth surface faces rearward.

[0138] According to the above aspect, the first and second pumps are disposed rearward of the multi-control valve. Furthermore, the third surface has a first pump port formed on one side in the third direction from the first connection port, and the fourth surface has a second pump port formed on one side in the third direction from the second connection port. Furthermore, the multi-control valve is disposed so that the fifth surface faces rearward. Therefore, the first and second pump ports can be disposed closer to the first and second pumps than the first and second connection ports. This makes it possible to prevent interference between the piping connecting the first and second pump ports and the first and second hydraulic pumps and the piping connecting the multi-control valve to the boom cylinder and the arm cylinder, thereby facilitating the piping layout.

[0139] In a fifteenth aspect, the construction machine is the construction machine of the thirteenth or fourteenth aspect, further comprising the tank arranged on the rotating body to the side of the multi-control valve, and the multi-control valve is arranged so that the fifth surface faces rearward.

[0140] According to the above aspect, the tank is disposed to the side of the multi-control valve on the rotating body, and the multi-control valve is disposed so that the fifth surface faces rearward. Therefore, the tank port and the tank can be easily attached by extending the piping laterally from the tank port.

[0141] From the above description, many modifications and other embodiments of the present disclosure will be apparent to those skilled in the art. Therefore, the above description should be construed as illustrative only and is provided for the purpose of teaching those skilled in the art the best mode for carrying out the present disclosure. Details of the structure and / or function thereof can be substantially changed without departing from the spirit of the present disclosure.

Claims

1. A multi-control valve connected to a first pump, a second pump, first to fourth actuators, and a tank, and controlling the flow of hydraulic fluid to each of the first to fourth actuators, the multi-control valve comprising: a valve block including a first pump port connected to the first pump, a second pump port connected to the second pump, first to fourth connection ports connected to each of the first to fourth actuators, and a tank port connected to the tank; a plurality of spools provided in the valve block so as to correspond to each of the first to fourth actuators and be slidable in a first direction, each spool being connected to at least one of the corresponding actuator, the first pump, the second pump, and the tank, and controlling the flow of hydraulic fluid to the corresponding actuator; and a plurality of spool covers provided in the valve block so as to cover each of the plurality of spools, wherein the valve block includes a first surface and a second surface on one side and the other side in the first direction, a third surface and a fourth surface on one side and the other side in a second direction intersecting the first direction, and a fifth surface on one side in a third direction intersecting the first and second directions; the plurality of spool covers are provided on the first surface and the second surface; the first pump port and the first connection port are formed on the third surface; the second pump port and the second connection port are formed on the fourth surface; and the tank port and the third and fourth connection ports are formed on the fifth surface.

2. The multi-control valve according to claim 1, wherein the first pump port is formed on the third surface on one side in the third direction from the first connection port, and the second pump port is formed on the fourth surface on one side in the third direction from the second connection port.

3. The multi-control valve according to claim 1, wherein the third connection port is a port connected to a first travel motor provided in a travel device of a construction machine, the fourth connection port is a port connected to a second travel motor provided in the travel device, the tank port is formed on the fifth surface on one side in the first direction, and the third and fourth connection ports are formed on the fifth surface on the other side in the first direction.

4. On the third surface, the first pump port is formed between the tank port and the third and fourth connection ports as viewed from one side in the third direction and on the one side in the third direction from the first connection port. On the fourth surface, the second pump port is formed between the tank port and the third and fourth connection ports as viewed from one side in the third direction and on the one side in the third direction from the second connection port. The multi-control valve according to claim 3.

5. The valve block includes two of the third connection ports and two of the fourth connection ports. The two third connection ports and the two fourth connection ports are arranged side by side in the second direction. The multi-control valve according to claim 3.

6. The plurality of spools includes two first spools provided in the valve block corresponding to the first actuator and two second spools provided in the valve block corresponding to the second actuator. The two first spools are arranged such that their respective axes coincide. The two second spools are arranged such that their respective axes coincide. The multi-control valve according to claim 1.

7. The valve block further includes a fifth connection port connected to the bucket cylinder of the construction machine and a sixth connection port connected to the slewing motor of the construction machine. The first connection port is a port connected to the boom cylinder of the construction machine. The second connection port is a port connected to the arm cylinder of the construction machine. On the third surface, the fifth connection port is further formed. On the fourth surface, the sixth connection port is formed. The multi-control valve according to claim 1.

8. The plurality of spools includes two boom spools provided in the valve block corresponding to the boom cylinder and two arm spools provided in the valve block corresponding to the arm cylinder. The two boom spools are arranged such that their respective axes coincide. The two arm spools are arranged such that their respective axes coincide. The multi-control valve according to claim 7.

9. The plurality of spools includes two bucket spools provided on the valve block corresponding to the bucket cylinder and two swivel spools provided on the valve block corresponding to the swivel motor. The two bucket spools are arranged such that their respective axes coincide. The two swivel spools are arranged such that their respective axes coincide. One of the two bucket spools is arranged adjacent to one of the two swivel spools in the second direction. The other of the two bucket spools is arranged adjacent to the other of the two swivel spools in the second direction. The multi-control valve according to claim 7.

10. The valve block includes two of the third connection ports and two of the fourth connection ports. One of the two third connection ports is formed on the fifth surface. The other of the two third connection ports is formed on the third surface. One of the two fourth connection ports is formed on the fifth surface. The other of the two fourth connection ports is formed on the fourth surface. The multi-control valve according to claim 1.

11. The two third connection ports are ports connected to a first travel motor provided in a travel device of a construction machine. The two fourth connection ports are ports connected to a second travel motor provided in the travel device. The multi-control valve according to claim 10.

12. A construction machine comprising a boom cylinder for driving a boom, an arm cylinder for driving an arm, a travel device including first and second travel motors, and the multi-control valve according to claim 1. The first connection port is a port connected to the boom cylinder. The second connection port is a port connected to the arm cylinder. The third connection port is a port connected to the first travel motor. The fourth connection port is a port connected to the second travel motor.

13. The construction machine according to claim 12, further comprising a slewing body rotatably provided on the traveling device, wherein the boom cylinder is disposed on the front side of the slewing body so as to be swingable in the vertical direction, and the multi-control valve is provided in the slewing body such that the third and fourth surfaces face one side and the other side in the left-right direction, respectively.

14. The construction machine according to claim 13, further comprising the first and second pumps disposed on the rear side of the multi-control valve in the slewing body, wherein the first pump port is formed on the third surface on one side in the third direction from the first connection port, the second pump port is formed on the fourth surface on one side in the third direction from the second connection port, and the multi-control valve is disposed such that the fifth surface faces rearward.

15. The construction machine according to claim 13, further comprising the tank disposed on the side of the multi-control valve in the slewing body, wherein the multi-control valve is disposed such that the fifth surface faces rearward.