Hydraulic valve device

Abstract

In order to efficiently supply more oil to a linear spool valve, provided is a hydraulic valve device (1) for controlling the supply of oil from a hydraulic pump to a hydraulic device by operating a spool valve provided in a valve body (20), the valve body (20) is provided with: two pump oil passages (21A, 21B) that are connected to a separate hydraulic pump (9) via pump ports (22A, 22B); and a plurality of cylinder slide valves (33) provided separately corresponding to the plurality of hydraulic cylinders (11, 12), in which the pump passages (21A, 21B) are provided in the valve body (20) so as to be parallel to each other in the same direction, and the plurality of cylinder slide valves (33) are connected to portions located on one side of the pump ports (22A, 22B) in the pump passages (21A, 21B). End portions of the pump oil passages (21A, 21B) located on one side of the pump ports (22A, 22B) are connected to each other via a combining / dividing oil passage (42) having a combining / dividing switching valve (44V).

Description

Technical Field

[0001] The present invention relates to a hydraulic valve device, and more particularly to a hydraulic valve device in which a plurality of direct-acting slide valves corresponding to direct-acting hydraulic equipment such as hydraulic cylinders are provided on a valve body. Background Art

[0002] In a hydraulic valve device for controlling the supply of oil to a plurality of hydraulic cylinders, two pump oil circuits are provided in a valve body, and each pump oil circuit is connected to a hydraulic pump via a pump port. A direct-acting slide valve for controlling the supply of oil to the hydraulic cylinder is connected to each pump oil circuit. In addition, a merging and diverting switching valve is provided between the two pump oil circuits. In this hydraulic valve device, by connecting the two pump oil circuits using a merging and diverting switching valve, there is an advantage that the oil supplied to one pump port and the oil supplied to the other pump port can be merged and supplied to the hydraulic cylinder (for example, refer to Patent Document 1).

[0003] Prior Art Literature

[0004] Patent Literature

[0005] Patent Document 1: Japanese Patent Application Laid-Open No. 3-140678 (Fig. 2) Summary of the invention

[0006] Problems to be solved by the invention

[0007] However, in the above-mentioned hydraulic valve device, the large flow of oil from the two hydraulic pumps that has passed through the flow combining and splitting switching valve passes through the portion of the pump oil path that is connected to the other direct-acting slide valve. Therefore, there is room for improvement when considering the pressure loss until the oil is supplied to the target direct-acting slide valve.

[0008] In view of the above-mentioned actual situation, an object of the present invention is to provide a hydraulic valve device capable of efficiently supplying a larger amount of oil to a direct-acting spool valve.

[0009] Means for solving problems

[0010] In order to achieve the above-mentioned purpose, the hydraulic valve device of the present invention is interposed between the hydraulic equipment and the hydraulic pump, and controls the supply of oil from the hydraulic pump to the hydraulic equipment by actuating the sliding valve arranged on the valve body, and is characterized in that the valve body has: two pump oil circuits, which are connected to a separate hydraulic pump via a pump port; and a plurality of direct-acting sliding valves, which are individually arranged corresponding to a plurality of direct-acting hydraulic equipment, the two pump oil circuits are arranged on the valve body in parallel with each other in the same direction, the plurality of direct-acting sliding valves are connected to a portion of the pump oil circuit located on one side of the pump port, and the ends of the two pump oil circuits located on the one side of the pump port are connected to each other via a merging and diverting oil circuit having a merging and diverting switching valve.

[0011] Effects of the Invention

[0012] According to the present invention, the oil that has passed through the merging and diverting switching valve does not merge with the oil supplied from other hydraulic pumps before reaching the target direct-acting sliding valve, and the flow rate of oil passing through the pump oil circuit becomes smaller. Therefore, more oil can be efficiently supplied to the target direct-acting sliding valve while suppressing the pressure loss to a minimum. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 This is a transparent perspective view conceptually showing the interior of a hydraulic valve device as an embodiment of the present invention.

[0014] Figure 2 It is conceptually expressed from another perspective. Figure 1 A perspective perspective view of the interior of a hydraulic valve arrangement is shown.

[0015] Figure 3A is Figure 1 The hydraulic valve device shown only shows the structure of the slide valve for the working device. Figure 1 Corresponding perspective stereogram.

[0016] Figure 3B is Figure 1 The hydraulic valve device shown only shows the structure of the slide valve for the working device. Figure 2 Corresponding perspective stereogram.

[0017] Figure 4A is Figure 1 The hydraulic valve device shown only shows the structure of the travel slide valve. Figure 1 Corresponding perspective stereogram.

[0018] Figure 4B is Figure 1 The hydraulic valve device shown only shows the structure of the travel slide valve. Figure 2 Corresponding perspective stereogram.

[0019] Figure 5A is Figure 1 The hydraulic valve device shown only shows the structure of the rotary slide valve. Figure 1 Corresponding perspective stereogram.

[0020] Figure 5B is Figure 1 The hydraulic valve device shown only shows the structure of the rotary slide valve. Figure 2 Corresponding perspective stereogram.

[0021] Fig. 6A It means to become Figure 1 A side view of a hydraulic valve device for a subject working machine is shown.

[0022] Figure 6B It means to become Figure 1 A rear view of a working machine of the subject is shown with a hydraulic valve device.

[0023] Figure 6C It means to become Figure 1 The hydraulic valve device shown is used in a plan view of a subject working machine.

[0024] Figure 7 It is a schematic representation of the application Figure 1 The hydraulic valve arrangement is shown in a top view of a hydraulic circuit of a working machine.

[0025] Figure 8 Observed from the front surface Figure 1 A front view of the hydraulic valve arrangement is shown.

[0026] Fig. 9 yes Figure 8 Left side view.

[0027] Fig.10 yes Figure 8 Right side view.

[0028] Fig.11 yes Figure 8 Rear view of.

[0029] Fig.12 yes Figure 8 Top view of the .

[0030] Fig.13 yes Figure 8 Bottom view of .

[0031] Fig.14 yes Figure 8 The X1-X1 line section view.

[0032] Fig.15 yes Figure 8 The X2-X2 line section view.

[0033] Fig.16 yes Figure 8 The X3-X3 line section view.

[0034] Fig.17 yes Figure 8 X4-X4 line section view. DETAILED DESCRIPTION

[0035] Hereinafter, preferred embodiments of the hydraulic valve device according to the present invention will be described in detail with reference to the accompanying drawings.

[0036] Figure 1 to Figure 5BThe hydraulic valve device 1 shown here is conceptually a hydraulic valve device as an embodiment of the present invention. Fig. 6A , Figure 6B , Figure 6C , Figure 7 As shown, a working machine having an upper slewing body 3, a boom 4, and a dipper arm 5 on the upper part of a lower traveling body 2 is used as an application object. The lower traveling body 2 is provided with crawlers 6 on both sides, and is provided with separate traveling hydraulic motors (rotating hydraulic equipment) 7 corresponding to each crawler 6, and can travel by driving the crawlers 6 via the traveling hydraulic motors 7. The upper slewing body 3 is supported so as to be rotatable around a slewing axis along the upper and lower sides relative to the lower traveling body 2. A slewing hydraulic motor (rotating hydraulic equipment) 8 is provided between the lower traveling body 2 and the upper slewing body 3 so as to enable the upper slewing body 3 to slew relative to the lower traveling body 2. The traveling hydraulic motor 7 and the slewing hydraulic motor 8 have two supply ports 7a and 8a, respectively, and can rotate in both forward and reverse directions by changing the oil supply direction. A hydraulic pump 9 is mounted on the upper slewing body 3. The hydraulic pump 9 is driven by an engine 10, and two hydraulic pumps with the same maximum discharge flow rate are prepared on the upper slewing body 3. In the example shown in the figure, an engine 10 is mounted on the left side of the rear part of the upper revolving body 3, and two hydraulic pumps 9 are mounted on the right side of the rear part of the upper revolving body 3 in a state adjacent to the engine 10. The boom 4 is rotatably supported on the upper revolving body 3 via a base end portion via a support shaft along the horizontal direction. The boom 5 is rotatably supported on the front end portion of the boom 4 via a support shaft along the horizontal direction via a base end portion. A boom hydraulic cylinder (direct-acting hydraulic equipment) 11 is provided between the upper revolving body 3 and the boom 4, and a boom hydraulic cylinder (direct-acting hydraulic equipment) 12 is provided between the boom 4 and the boom 5. The boom hydraulic cylinder 11 and the boom hydraulic cylinder 12 are single-rod double-acting hydraulic cylinders each having a single piston rod. The boom hydraulic cylinder 11 is supported on the upper revolving body 3 via a cylinder body 11a, and is supported on the boom 4 via a piston rod 11b. The arm hydraulic cylinder 12 is supported by the boom 4 via a cylinder body 12 a and is supported by the arm 5 via a piston rod 12 b .

[0037] The hydraulic valve device 1 is interposed between the travel hydraulic motor 7, the swing hydraulic motor 8, the boom hydraulic cylinder 11, the arm hydraulic cylinder 12 (hereinafter, sometimes collectively referred to as hydraulic equipment) and the hydraulic pump 9, and controls the supply of oil from the hydraulic pump 9 to the hydraulic equipment 7, 8, 11, 12. Figure 1 As shown in FIG. 1 , a valve body 20 is provided. The valve body 20 is configured to Figure 1 In the following description, for convenience, Figure 1The surface located in front of the right side of the valve body 20 is called the front surface 20a, the surface parallel to the front surface 20a is called the rear surface 20b, and the two surfaces located on both sides are called side surfaces 20c and 20d. Figure 1 In the figure, the surface located at the top is referred to as an upper surface 20e, and the surface located at the bottom is referred to as a lower surface 20f.

[0038] like Figure 1 to Figure 5B , Figure 8 to Figure 17 As shown, two pump oil circuits 21A and 21B are provided inside the valve body 20. The pump oil circuits 21A and 21B extend linearly along the up and down directions of the valve body 20, respectively, and are formed to have the same inner diameter as each other. In the illustrated example, the two pump oil circuits 21A and 21B are arranged side by side in left-right symmetrical positions in a state where the portions biased toward the rear surface 20b are parallel to each other. Although not explicitly shown in the figure, the lower ends of the two pump oil circuits 21A and 21B are both blocked. In the case where the lower ends of the pump oil circuits 21A and 21B are blocked, a plug can also be installed after the oil circuit is temporarily formed. The upper ends of the two pump oil circuits 21A and 21B open at the upper surface 20e of the valve body 20, respectively. In the present embodiment, each pump oil circuit 21A and 21B is connected to a separate hydraulic pump 9 via pump ports 22A and 22B. The pump ports 22A and 22B extend linearly from the pump oil passages 21A and 21B toward the rear, and open at the rear surface 20b of the valve body 20. Although not clearly shown in the drawings, the distances from the pump ports 22A and 22B to the hydraulic pump 9 are equal to each other.

[0039] In each of the pump oil passages 21A and 21B, two cylinder spool holes 23 are provided above and below the portion located above the connection portion with the pump ports 22A and 22B. In addition, in each of the pump oil passages 21A and 21B, one travel spool hole 24 is provided below the portion located below the connection portion with the pump ports 22A and 22B. Moreover, in the pump oil passage 21A disposed on the left side when viewed from the front surface 20a of the valve body 20, one swing spool hole 25 is provided below the travel spool hole 24. The cylinder spool hole 23, the travel spool hole 24, and the swing spool hole 25 extend linearly along the front-rear direction of each valve body 20, and are connected to each of the pump oil passages 21A and 21B by penetrating the corresponding pump oil passages 21A and 21B. Both ends of each of the spool holes 23, 24, and 25 are closed.

[0040] In the cylinder spool hole 23, a cylinder port 23a is provided at a portion close to the front surface 20a of the valve body 20. The cylinder port 23a extends from the side portions facing the side surfaces 20c and 20d of the valve body 20 in each cylinder spool hole 23 toward the side surfaces 20c and 20d, respectively, and then bends toward the front surface 20a to open at the front surface 20a of the valve body 20. The cylinder port 23a opened at the upper right when viewed from the front surface 20a of the valve body 20 is connected to the boom rod oil passage 11Ha to be communicated with the rod chamber 11H of the boom hydraulic cylinder 11. The cylinder port 23a opened at the lower right when viewed from the front surface 20a of the valve body 20 is connected to the boom bottom oil passage 11Ba to be communicated with the bottom chamber 11B of the boom hydraulic cylinder 11. Similarly, the cylinder port 23a opened at the upper left when viewed from the front surface 20a of the valve body 20 is connected to the bottom oil path 12Ba for the boom that communicates with the bottom chamber 12B of the boom hydraulic cylinder 12. The cylinder port 23a opened at the lower left when viewed from the front surface 20a of the valve body 20 is connected to the rod oil path 12Ha for the boom that communicates with the rod chamber 12H of the boom hydraulic cylinder 12.

[0041] In the travel slide valve hole 24, travel motor ports 24a1 and 24a2 are provided at the portions close to the middle portion and the front surface 20a side of the valve body 20, respectively. The travel motor port 24a1 provided at the middle portion of the travel slide valve hole 24 extends from the upper portion facing the upper surface 20e of the valve body 20 toward the upper surface 20e, bends toward the front surface 20a side, and opens at the front surface 20a of the valve body 20. The travel motor port 24a2 provided at the portion close to the front surface 20a of the valve body 20 extends from the side portions facing the side surfaces 20c and 20d of the valve body 20 toward the side surfaces 20c and 20d, bends toward the front surface 20a side, and opens at the front surface 20a of the valve body 20. The two travel motor ports 24a1 and 24a2 opened on the left side when viewed from the front surface 20a of the valve body 20 are connected to the travel hydraulic motor oil passages 24MA1 and 24MA2, respectively, which are communicated with the supply port 7a of the travel hydraulic motor 7 arranged on the right side of the lower travel body 2. The two travel motor ports 24a1 and 24a2 opened on the right side when viewed from the front surface 20a of the valve body 20 are connected to the travel hydraulic motor oil passages 24MB1 and 24MB2, respectively, which are communicated with the supply port 7a of the travel hydraulic motor 7 arranged on the left side of the lower travel body 2. The oil supply conditions to the respective travel hydraulic motors 7 are the same on the left and right sides. In other words, the path length of the travel hydraulic motor oil circuit 24MA1+24MA2 connected to the travel hydraulic motor 7 on one side and the path length of the travel hydraulic motor oil circuit 24MB1+24MB2 connected to the travel hydraulic motor 7 on the other side are equal to each other, and the inner diameters of the travel hydraulic motor oil circuits 24MA1, 24MA2, 24MB1, and 24MB2 are also the same.

[0042] In the swing valve hole 25, swing motor ports 25a1 and 25a2 are provided at the portions close to the middle portion and the front surface 20a side of the valve body 20, respectively. The swing motor port 25a1 provided at the middle portion of the swing valve hole 25 extends from the side portion opposite to the right side surface 20d when viewed from the front surface 20a of the valve body 20 toward the side surface 20d, bends toward the front surface 20a side, and opens at the front surface 20a of the valve body 20. The swing motor port 25a2 provided at the portion close to the front surface 20a of the valve body 20 extends from the side portion opposite to the left side surface 20c when viewed from the front surface 20a of the valve body 20 toward the side surface 20c, bends toward the front surface 20a side of the valve body 20, and opens at the front surface 20a of the valve body 20. The two swing motor ports 25a1 and 25a2 are connected to the swing hydraulic motor oil passage 25M that communicates with the supply port 8a of the swing hydraulic motor 8, respectively.

[0043] Separate slide valves are provided in the cylinder slide valve hole 23, the travel slide valve hole 24, and the rotation slide valve hole 25, respectively. Although not explicitly shown in the figure, the slide valve moves in the axial direction when a pilot pressure is applied from a separate EPC valve (electromagnetic proportional control valve). More specifically, the cylinder slide valve (direct-acting slide valve) 33 provided in the cylinder slide valve hole 23 switches the intermittent state between the pump oil passages 21A, 21B and the cylinder port 23a by moving in the axial direction, and the cylinder direction switching valve 33V is formed by the cylinder slide valve hole 23. Similarly, the travel slide valve (rotation slide valve) 34 provided in the travel slide valve hole 24 switches the intermittent state between the pump oil passages 21A, 21B and the travel motor ports 24a1, 24a2 by moving in the axial direction, and the travel direction switching valve 34V is formed by the travel slide valve hole 24. The rotary slide valve (rotation slide valve) 35 disposed in the rotary slide valve hole 25 switches the intermittent state between the pump oil passage 21A and the rotary motor ports 25a1 and 25a2 by moving in the axial direction, and constitutes a rotary direction switching valve 35V through the rotary slide valve hole 25. Although not explicitly shown in the figure, a plurality of EPC valves corresponding to the respective slide valves 33, 34, and 35 are accommodated in an accommodation box EPCB provided on the rear surface 20b of the valve body 20.

[0044] In addition, a unit block 41 of the merging and diverting switching unit 40 is disposed on the upper surface 20e of the valve body 20. The unit block 41 has a size that can simultaneously cover the openings of the two pump oil passages 21A and 21B opened on the upper surface 20e of the valve body 20, and has a merging and diverting oil passage 42 and a valve core hole 43 inside. After the merging and diverting oil passage 42 extends in the left-right direction inside the unit block 41, each end is bent downward and opens on the lower surface of the unit block 41. The merging and diverting oil passage 42 is connected to the upper ends of the pump oil passages 21A and 21B respectively via the lower end opening. The valve core hole 43 extends linearly in the front-to-back direction, and is connected to the merging and diverting oil passage 42 by penetrating the middle part of the part extending to the left and right in the merging and diverting oil passage 42. Both ends of the valve core hole 43 are blocked. A merging and diverting slide valve 44 is disposed in the valve core hole 43. The merging and splitting spool valve 44 moves in the axial direction when a pilot pressure is applied from the EPC valve, thereby switching the intermittent state of the merging and splitting oil passage 42 , and forming a merging and splitting switching valve 44V through the spool hole 43 .

[0045] The hydraulic valve device 1 is mounted on the upper slewing body 3 at a position that is forward of the engine 10 and substantially in the center in the left-right direction, with the front surface 20a of the valve body 20 facing the front of the working machine and the upper surface 20e facing upward. In the working machine equipped with the hydraulic valve device 1, when the operating lever (not shown) is operated, the corresponding slide valves 33, 34, 35, 44 are appropriately operated via the EPC valve, and the supply state of the oil from the hydraulic pump 9 to the hydraulic devices 7, 8, 11, 12 is changed. For example, when the pump oil path 21B and the cylinder port 23a are connected by the operation of the cylinder slide valve 33 disposed in the upper right portion when viewed from the front surface 20a of the valve body 20, the oil from the hydraulic pump 9 is supplied to the rod chamber 11H of the boom hydraulic cylinder 11 via the pump oil path 21B, the cylinder port 23a, and the boom rod oil path 11Ha. As a result, the boom hydraulic cylinder 11 retracts, and the front end of the boom 4 can be moved downward relative to the working machine. Similarly, when the pump oil path 21A and the cylinder port 23a are connected by the operation of the cylinder slide valve 33 disposed in the upper left portion when viewed from the front surface 20a of the valve body 20, the oil from the hydraulic pump 9 is supplied to the bottom chamber 12B of the boom hydraulic cylinder 12 via the pump oil path 21A, the cylinder port 23a, and the boom bottom oil path 12Ba. As a result, the boom hydraulic cylinder 12 extends, and the front end of the boom 5 can be pulled closer to the upper swing body 3 relative to the working device.

[0046] During this period, in a state where the merging and splitting oil passage 42 is cut off by the merging and splitting slide valve 44, oil is supplied to the hydraulic cylinders 11 and 12 through either of the pump oil passages 21A and 21B. On the other hand, when the merging and splitting oil passage 42 is connected by the merging and splitting slide valve 44, the oil supplied from the one hydraulic pump 9 to the one pump oil passage 21A and the oil supplied from the other hydraulic pump 9 to the other pump oil passage 21B can be combined in the valve body 20. Thus, oil can also be supplied from the other pump oil passage 21B to the cylinder port 23a connected to the one pump oil passage 21A, and the operation of the hydraulic cylinders 11 and 12 can be accelerated. Furthermore, according to the above-mentioned hydraulic valve device 1, the merging and splitting switching valve 44V composed of the merging and splitting slide valve 44 is provided in the merging and splitting oil passage 42 connecting the upper ends of the respective pump oil passages 21A and 21B, and the cylinder slide valve 33 is connected to the portion located above the connection portion with the pump ports 22A and 22B in the respective pump oil passages 21A and 21B. Therefore, the oil passing through the merging and splitting switching valve 44V does not pass through the travel slide valve 34 and the swing slide valve 35 arranged below the connection portion with the pump ports 22A and 22B before reaching the target cylinder slide valve 33. Furthermore, the oil passing through the merging and splitting switching valve 44V does not merge with the oil supplied from the other hydraulic pump 9 before reaching the target cylinder slide valve 33, so that the pressure loss in the oil passage can be suppressed. As a result, more oil can be efficiently supplied to the target cylinder slide valve 33 while suppressing the pressure loss to a minimum.

[0047] On the other hand, if the operating lever is operated to supply oil to the travel hydraulic motor 7, the working machine can be driven via the crawler 6, and if oil is supplied to the swing hydraulic motor 8, the upper swing body 3 can be swung relative to the lower travel body 2. Here, according to the above-mentioned hydraulic valve device 1, in each of the pump oil passages 21A and 21B, a travel slide valve 34 is provided at a portion located below the connection portion with the pump ports 22A and 22B. The paths of oil from the pump ports 22A and 22B to each of the travel slide valves 34 are the same. Moreover, the travel slide valve 34 is initially connected to the portion located below the pump ports 22A and 22B, and no other slide valves 33 and 35 exist. In other words, according to the above-mentioned hydraulic valve device 1, there is no problem caused by the difference in the length of the oil passage to the two travel slide valves 34, and there is no problem caused by the difference in pressure loss. As a result, when the straight-moving operation is performed by the operating lever, the supply pressure and the supply flow rate of oil to the two travel slide valves 34 can be made equal, and the straight-moving performance of the working machine to which it is applied can be improved.

[0048] It should be noted that, in the above-mentioned embodiment, as the direct-acting slide valve, a structure having four cylinder slide valves 33 provided corresponding to the boom 4 and the dipper arm 5 of the working machine is exemplified, but a hydraulic valve device may be provided with a direct-acting slide valve provided corresponding to other direct-acting hydraulic equipment (hydraulic cylinder). For example, in the case of the above-mentioned working machine, a hydraulic valve device may be provided with a bucket slide valve provided corresponding to a bucket hydraulic cylinder for actuating the bucket 13 provided at the front end of the dipper arm 5.

[0049] Furthermore, in the above-described embodiment, the swing slide valves 34 and 35 are provided corresponding to the hydraulic motors 7 and 8 as swing-type hydraulic devices, but the swing slide valves 34 and 35 are not necessarily required.

[0050] Description of Reference Numerals

[0051] 1Hydraulic valve device

[0052] 7. Travel hydraulic motor

[0053] 8-turn hydraulic motor

[0054] 9. Hydraulic pump

[0055] 11Hydraulic cylinder for boom

[0056] 12 Hydraulic cylinder for bucket arm

[0057] 20 Valve body

[0058] 21A, 21B pump oil circuit

[0059] 22A, 22B pump ports

[0060] 33 cylinder slide valve

[0061] 34 Travel slide valve

[0062] 35-turn slide valve

[0063] 42 oil split line

[0064] 44V flow combining and diverting switching valve.

Claims

1. A hydraulic valve device, which is interposed between a hydraulic device and a hydraulic pump, and controls the supply of oil from the hydraulic pump to the hydraulic device by actuating a slide valve provided in a valve body, wherein: The valve body comprises: two pump oil circuits connected to separate hydraulic pumps via pump ports; and A plurality of direct-acting slide valves are individually provided corresponding to a plurality of direct-acting hydraulic devices. The two pump oil passages are arranged on the valve body in parallel with each other in the same direction. The plurality of direct-acting slide valves are connected to a portion of the pump oil passage located on one side of the pump port. Ends of the two pump oil passages located on one side of the pump port are connected to each other via a merging and splitting oil passage having a merging and splitting switching valve.

2. The hydraulic valve device according to claim 1, characterized in that: The valve body includes a rotary slide valve corresponding to a rotary hydraulic device. The pump port is arranged in the middle of each pump oil circuit. The rotation slide valve is connected to a portion of the pump oil passage located on the other side of the pump port.

3. The hydraulic valve device according to claim 2, characterized in that: The swing slide valve controls the supply of oil to the travel hydraulic motor, and is provided with two slide valves in the valve body. The slide valves are connected to separate pump oil passages at positions equidistant from the pump port without intervening other slide valves.

4. A hydraulic valve device, which is interposed between a hydraulic device and a hydraulic pump, and controls the supply of oil from the hydraulic pump to the hydraulic device by actuating a slide valve provided in a valve body, characterized in that: The valve body has: two pump oil circuits connected to separate hydraulic pumps via pump ports; a plurality of direct-acting slide valves, which are individually provided corresponding to a plurality of direct-acting hydraulic devices; and Rotary slide valve, which corresponds to rotary hydraulic equipment, The two pump oil passages are arranged on the valve body in parallel with each other in the same direction. The pump port is arranged in the middle of each pump oil circuit. The plurality of direct-acting slide valves are connected to a portion of the pump oil passage located on one side of the pump port. The rotary slide valve is connected to a portion of the pump oil passage located on the other side of the pump port. Ends of the two pump oil passages on the side connected to the plurality of direct-acting slide valves are connected to each other via a merging and splitting oil passage having a merging and splitting switching valve.

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