Hydraulic valve device

Abstract

To efficiently recover oil while suppressing size increase, a valve body 30a is provided with a first slide 41A, which controls the oil supply to a bottom chamber 12 of an arm hydraulic cylinder 10, and a second slide 41B, which controls the oil supply to a rod chamber 11. The valve body 30a includes an axial bottom oil channel section 43A2 of a bottom oil channel 43A, which is provided parallel to an axial direction of a second arm slide hole 32 and is arranged side by side with the second arm slide hole 32. The second arm slide hole 32 is provided with a recovery port 32d. A recovery oil channel 46A is provided between the recovery port 32d and the axial bottom oil channel section 43A2, allowing the passage of oil from the recovery port 32d to the bottom oil channel 43A.The recovery port 32d is connected to a second outlet port 32c if a first inlet port 31b is connected to a first pump oil supply port 31a.

Description

TECHNICAL AREA

[0001] The present invention relates to a hydraulic valve device with a recovery circuit which supplies oil discharged from one oil chamber of a hydraulic cylinder to another oil chamber. STATE OF THE ART

[0002] Some hydraulic valve devices that control the oil supply to a hydraulic cylinder include a recovery circuit. In this type of hydraulic valve device, for example, when an actuating rod of the hydraulic cylinder is moved backward, in addition to the oil supplied by a hydraulic pump, the oil discharged from a bottom chamber can be fed back into (recovered from) a rod chamber, offering advantages such as the ability to move the actuating rod backward quickly and improving fuel efficiency (see, for example, patent document 1). List of oppositions patent literature

[0003] Patent document 1: JP 08-100803 A BRIEF DESCRIPTION OF THE INVENTION Technical Problem

[0004] In the hydraulic valve device described above, a first inlet port and a first outlet port are provided at one end section of a valve. A first oil channel extends from the first inlet port along the radial direction of the valve and is connected to the bottom chamber of the hydraulic cylinder. At another end section of the valve, a second inlet port and a second outlet port are provided. A second oil channel extends from the second inlet port along the radial direction of the valve and is connected to the rod chamber of the hydraulic cylinder.

[0005] The recovery circuit described above is configured by providing a recovery port at one end of the slide valve and a recovery oil channel connecting the recovery port and the second inlet port. That is, the recovery oil channel is positioned side-by-side with the slide valve along the axial direction from one end to the other.

[0006] To efficiently route oil through the recovery circuit, it is preferable to ensure a large cross-sectional area of ​​the recovery oil channel and to shorten its path length. However, in addition to the above, the recovery circuit must extend from one end section to the other of the valve, making it difficult to shorten the path length. Furthermore, ensuring a large cross-sectional area would necessitate increasing the external dimensions of the valve body, potentially increasing the overall size of the device.

[0007] In view of the aforementioned circumstances, an object of the present invention is to provide a hydraulic valve device that is able to efficiently recover oil while suppressing size increase. Solution to the problem

[0008] To solve the above problem, a hydraulic valve device according to the present invention is characterized in that: a valve main body is provided with a first slide valve that controls the oil supply to a first oil chamber of a hydraulic cylinder, and a second slide valve that controls the oil supply to a second oil chamber of the hydraulic cylinder; a first slide valve orifice that receives the first slide valve is provided with a first pump oil supply port that is connected to a hydraulic pump, a first inlet port and a first outlet port that are connected to the first oil chamber via a first oil channel, and a first tank port that is connected to a tank;a second valve hole, which accommodates the second valve, with a second pump oil supply port connected to the hydraulic pump, a second inlet port and a second outlet port connected to the second oil chamber via a second oil channel, and a second tank port connected to the tank; the first oil channel includes a first oil channel section provided parallel to an axial direction of the second valve hole and arranged side by side with the second valve hole; the second valve hole is provided with a recovery port, and a recovery oil channel is provided between the recovery port and the first oil channel section, allowing the passage of oil from the recovery port to the first oil channel section; and the recovery port is connected to the second outlet port when the oil is discharged from the second oil chamber. ADVANTAGEOUS EFFECTS OF THE INVENTION

[0009] Since, according to the present invention, the first oil channel section of the first oil channel is provided parallel to the axial direction of the second valve hole and is arranged side by side with the second valve hole, the path length of the recovery oil channel, which connects the recovery port provided at the second valve hole and the first oil channel section, can be shortened. Accordingly, an increase in the external dimensions of the valve body can be suppressed even when a large cross-sectional area of ​​the recovery oil channel is ensured, which is also preferable with regard to the strength of the valve body. BRIEF DESCRIPTION OF THE DRAWINGS Fig. Figure 1 is a diagram illustrating a hydraulic drive circuit in which a hydraulic valve device according to an embodiment of the present invention is used. Fig. 2 is a side view of a working machine, including a hydraulic cylinder that is guided by the in Fig. The hydraulic drive circuit shown in section 1 is controlled. Fig. Figure 3 is a perspective view that schematically illustrates a main part of the hydraulic valve device used in the hydraulic drive circuit of Fig. 1 is used. Fig. 4 is a perspective view that schematically shows the main part of the in Fig. 3. The hydraulic valve device is illustrated from a different angle. Fig. 5 is a perspective view that schematically shows the main part of the in Fig. 3 illustrated hydraulic valve device from yet another angle. Fig. 6 is a diagram that schematically shows the main part of the in Fig. Figure 3 illustrates a hydraulic valve device as seen from the front. Fig. Figure 7 is a diagram of the appearance of the hydraulic valve device, which is used in the hydraulic drive circuit of Fig. 1 is used, viewed from the front. Fig. Figure 8 is a cross-sectional view along a line YY in Fig. 7. Fig. Figure 9 is a cross-sectional view along a line ZZ in Fig. 7. Fig. Figure 10 is a cross-sectional view along a line XX in Fig. 8. DESCRIPTION OF EXECUTION FORMS

[0010] A preferred embodiment of a hydraulic valve device according to the present invention is described in detail below with reference to the accompanying drawings.

[0011] Fig. Figure 1 illustrates a hydraulic drive circuit in which the hydraulic valve device is used as an embodiment of the present invention. The hydraulic drive circuit illustrated here by way of example is configured to drive two hydraulic cylinders 10 and 20 with oil supplied by both hydraulic pumps 1A and 1B.

[0012] Hydraulic pumps 1A and 1B are variable displacement pumps in which the displacement is changed by altering the tilt angle of a swashplate or an inclined shaft. In the hydraulic drive circuit of the present embodiment, the two hydraulic pumps 1A and 1B, which have the same configuration and size, are used. In the following description, in a case where the two hydraulic pumps are to be distinguished, the one on the left-hand side is referred to as... Fig. The hydraulic pump provided is designated as the first hydraulic pump 1A and the hydraulic pump provided on the right side is designated as the second hydraulic pump 1B.

[0013] In each of the hydraulic cylinders 10 and 20, an actuating rod moves back and forth relative to a cylinder main body by selectively supplying oil to a corresponding rod chamber and a corresponding bottom chamber. In the present embodiment, as shown in Fig. Figure 2 illustrates the objectives of oil supply control provided by a boom hydraulic cylinder 10 and a jib hydraulic cylinder 20 on a working machine. That is, the working machine includes a jib BM and a boom AM. The boom BM is rotatably mounted via a base end section on an upper rotary body JS by a boom shaft S1 extending horizontally. The boom AM is rotatably mounted via a base end section on a front end section of the boom BM by a boom shaft S2 extending parallel to the boom shaft S1. The boom hydraulic cylinder 10 is located between the boom BM and the boom AM, and the jib hydraulic cylinder 20 is located between the upper rotary body JS and the boom BM. Both the boom hydraulic cylinder 10 and the jib hydraulic cylinder 20 are double-acting single-rod type and equipped with a single actuating rod.

[0014] As in Fig. As illustrated in Figure 1, a hydraulic valve assembly 30 is provided in the hydraulic drive circuit between the hydraulic pumps 1A, 1B and the hydraulic cylinders 10, 20. The hydraulic valve assembly 30 includes a boom direction switching valve 2A, which selectively connects the first hydraulic pump 1A to a rod chamber (second oil chamber) 11 and a bottom chamber (first oil chamber) 12 of the boom hydraulic cylinder 10, and a boom direction switching valve 2B, which selectively connects the second hydraulic pump 1B to a rod chamber (first oil chamber) 21 and a bottom chamber (second oil chamber) 22 of the boom hydraulic cylinder 20. The hydraulic valve assembly 30 includes a valve body 30a with two supply oil channels 3A and 3B, a reservoir oil channel 4, and four spools 41A, 41B, 42A, and 42B.

[0015] The valve main body 30a has the form of a single block and is, for example, designed in an essentially rectangular parallelepiped shape, as shown schematically in the Fig. Figures 3 to 6 illustrate this. The two supply oil channels 3A and 3B are linear spaces formed inside the valve body 30a such that they have the same inner diameter and are arranged so that their central axes are parallel to each other. The two supply oil channels 3A and 3B are connected to the hydraulic pumps 1A and 1B, respectively, and can supply oil. For the sake of simplicity, the following description assumes that the two supply oil channels 3A and 3B are arranged along an up-down direction of the valve body 30a, such that they are offset to one side of the rear surface of the valve body 30a. When distinguishing between the two supply oil channels 3A and 3B, the supply oil channel connected to the first hydraulic pump 1A is referred to as the first supply oil channel 3A, and the supply oil channel connected to the second hydraulic pump 1B is referred to as the second supply oil channel 3B.Although not illustrated in the drawings, the tank oil channel 4 is a linear space formed inside the valve main body 30a and is provided along the up-down direction of the valve main body 30a and in a position offset towards the front. The tank oil channel 4 is connected to a tank T, as shown in . Fig. 1 illustrates.

[0016] The four slide valves 41A, 41B, 42A and 42B control the oil supply to each of the hydraulic cylinders 10 and 20 in pairs and are arranged in the main valve body 30a, as shown in the Fig. 3 to 6 illustrated. As in the Fig. 8 and Fig. As illustrated in Figure 9, the slides 41A, 41B, 42A, and 42B each have a circular cylindrical shape with a plurality of web sections divided by annular grooves. These slides 41A, 41B, 42A, and 42B are provided such that their respective central axes are parallel to each other and orthogonal to the axial direction of the supply oil channels 3A and 3B, and are each mounted on slide holes 31, 32, 33, and 34 provided in the valve body 30a in a movable position along their respective axial directions.

[0017] In the present embodiment, as in the Fig. 1, Fig. 5 and Fig. Figure 7 illustrates two slides (hereinafter referred to as arm slides 41A and 41B when distinguished from one another) for forming the arm direction switching valve 2A are provided vertically side by side along the axial direction of the first supply oil channel 3A, and two slides (hereinafter referred to as cantilever slides 42A and 42B when distinguished from one another) for forming the cantilever direction switching valve 2B are provided vertically side by side along the axial direction of the second supply oil channel 3B. The two arm slides 41A and 41B and the two cantilever slides 42A and 42B are arranged side by side in a left-right direction. Hereinafter, viewed from the front, the upper left arm slide is referred to as the first arm slide (first slide) 41A, and the lower left arm slide is referred to as the second arm slide (second slide) 41B.Similarly, viewed from the front, the cantilever slide located at the top right is designated as the first cantilever slide (first slide) 42A and the cantilever slide located at the bottom right is designated as the second cantilever slide (second slide) 42B.

[0018] A first arm valve hole (first valve hole) 31, which receives the first arm valve 41A, is connected to a first pump oil supply port 31a, a first inlet port 31b, a first outlet port 31c and a first tank port 31d in that order from one side of the end section on the lower side in Fig. 8 accidentally. When the first arm slide 41A moves along the axial direction, the connection state of the first pump oil supply port 31a and the first tank port 31d is switched with respect to the first inlet port 31b and the first outlet port 31c.

[0019] In particular, when the first valve arm 41A is in a neutral position, both the first inlet port 31b and the first outlet port 31c are in a state in which they are disconnected from the first pump oil supply port 31a and the first tank port 31d. When the first valve arm 41A moves from the neutral position into Fig. 8 moved downwards (to the left side in Fig. 1) The first inlet port 31b is connected to the first pump oil supply port 31a, while the first outlet port 31c and the first tank port 31d remain in a separate state. When the first arm slide 41A moves upwards from the neutral position into Fig. 8 moved (to the right side in Fig. 1) The first inlet port 31b remains in a separate state, while the first outlet port 31c and the first tank port 31d are in a connected state. Both the first inlet port 31b and the first outlet port 31c are connected to the bottom chamber 12 of the arm hydraulic cylinder 10 via a bottom oil channel (first oil channel) 43A. A load check valve 43Aa, which allows oil to pass only to the bottom chamber 12, is provided on the bottom oil channel 43A, which extends from the first inlet port 31b to a rod chamber 11. As in Fig. As illustrated in Figures 3 to 6 and 8, the bottom oil channel 43A includes a radial bottom oil channel section 43A1, which is provided along the radial direction of the first arm valve hole 31 from the first inlet port 31b and the first outlet port 31c, and an axial bottom oil channel section (first oil channel section) 43A2, which is provided parallel to the axial direction of the first arm valve hole 31, such that it extends from an end section of the radial bottom oil channel section 43A1 to a front surface of the valve main body 30a. The axial bottom oil channel section 43A2 is located above a second arm valve hole 32, which accommodates the second arm valve 41B, and is provided side by side with the first arm valve hole 31 in the left-right direction.The first pump oil supply port 31a is connected to the first supply oil channel 3A via a branch supply oil channel 44, and the first tank port 31d is connected to the tank oil channel 4 via a drain oil channel 45.

[0020] The second arm valve hole 32 is connected to a second pump oil supply port 32a, a second inlet port 32b, a second outlet port 32c, a recovery port 32d and a second tank port 32e in that order from one side of the end section on the lower side in Fig. 9. When the second arm slide 41B moves along the axial direction, the connection state of the second pump oil supply port 32a and the second tank port 32e is switched with respect to the second inlet port 32b and the second outlet port 32c.

[0021] In particular, when the second valve arm 41B is in a neutral position, both the second inlet port 32b and the second outlet port 32c are in a state in which they are disconnected from the second pump oil supply port 32a, the recovery port 32d, and the second tank port 32e. When the second valve arm 41B moves from the neutral position into Fig. 9 moved downwards (to the left side in Fig. 1) The second outlet port 32c is connected to the recovery port 32d and the second tank port 32e, while the second inlet port 32b and the second pump oil supply port 32a remain in a separate state. When the second arm slide 41B moves upwards from the neutral position into Fig. 9 moves (to the right side in Fig. 1) the second outlet port 32c and the recovery port 32d remain in a separate state, while the second inlet port 32b and the second pump oil supply port 32a are in a state in which they are connected to each other.

[0022] Both the second inlet port 32b and the second outlet port 32c are connected to the rod chamber 11 of the arm hydraulic cylinder 10 via a rod oil channel (second oil channel) 43B. A load check valve 43Ba, which allows oil to pass only to the rod chamber 11, is provided on the rod oil channel 43B, which extends from the second inlet port 32b to the rod chamber 11. As in Fig. As illustrated in Figures 3 to 6 and 10, the rod oil channel 43B includes a radial rod oil channel section 43B1, which is provided along the radial direction of the second arm valve hole 32 from the second inlet port 32b and the second outlet port 32c, and an axial rod oil channel section (second oil channel section) 43B2, which is provided parallel to the axial direction of the second arm valve hole 32, such that it extends from an end section of the radial rod oil channel section 43B1 to the front surface of the valve main body 30a. The axial rod oil channel section 43B2 is located below the axial bottom oil channel section 43A2 and is provided side by side with the second arm valve hole 32 in a left-right direction. The second pump oil supply port 32a is connected to the first supply oil channel 3A via the branch supply oil channel 44, and the second tank port 32e is connected to the tank oil channel 4 via the drain oil channel 45.

[0023] As in the Fig. As illustrated in Figures 3 to 6 and 10, the recovery port 32d of the second arm valve hole 32 is connected to the axial bottom oil channel section 43A2 of the bottom oil channel 43A via a recovery oil channel 46A provided on the valve main body 30a. The recovery oil channel 46A is arranged to slope upwards from the recovery port 32d in a direction that gradually approaches the axial bottom oil channel section 43A2 and is connected to the bottom oil channel 43A at a section downstream of the load check valve 43Aa. The recovery oil channel 46A is provided with a recovery check valve 46Aa that allows oil to pass only from the recovery port 32d to the bottom oil channel 43A.

[0024] A first boom slide hole (first slide hole) 33, which accommodates the first boom slide 42A, is connected to a first pump oil supply port 33a, a first inlet port 33b, a first outlet port 33c and a first tank port 33d in that order from one side of the end section on the lower side in Fig. 8. When the first boom slide 42A moves along the axial direction, the connection state of the first pump oil supply port 33a and the first tank port 33d is switched with respect to the first inlet port 33b and the first outlet port 33c.

[0025] In particular, when the first boom valve 42A is in a neutral position, both the first inlet port 33b and the first outlet port 33c are in a state in which they are disconnected from the first pump oil supply port 33a and the first tank port 33d. When the first boom valve 42A moves from the neutral position into Fig. 8 moved downwards (to the right side in Fig. 1) The first inlet port 33b is connected to the first pump oil supply port 33a, while the first outlet port 33c and the first tank port 33d remain in a separate state. When the first boom slide 42A moves upwards from the neutral position into Fig. 8 moved (to the left side in Fig. 1) the first inlet port 33b remains in a separate state, while the first outlet port 33c and the first tank port 33d are in a state in which they are connected to each other.

[0026] Both the first inlet port 33b and the first outlet port 33c are connected via a rod oil channel (first oil channel) 47B to a rod chamber 21 of the boom hydraulic cylinder 20. A load check valve 47Ba, which allows oil to pass only to the rod chamber 21, is provided on the rod oil channel 47B, which extends from the first inlet port 33b to the rod chamber 21. As in Fig. As illustrated in Figures 3 to 6 and 8, the rod oil channel 47B includes a radial rod oil channel section 47B1, which is provided along the radial direction of the first cantilever valve hole 33 from the first inlet port 33b and the first outlet port 33c, and an axial rod oil channel section (first oil channel section) 47B2, which is provided parallel to the axial direction of the first cantilever valve hole 33, such that it extends from an end section of the radial rod oil channel section 47B1 to the front surface of the valve main body 30a. The axial rod oil channel section 47B2 is located above a second cantilever valve hole (second valve hole) 34, which accommodates the second cantilever valve 42B, and is provided side by side with the first cantilever valve hole 33 in the left-right direction.The first pump oil supply port 33a is connected to the second supply oil channel 3B via a branch supply oil channel 48, and the first tank port 33d is connected to the tank oil channel 4 via a drain oil channel 49.

[0027] The second boom valve hole 34 is connected to a second pump oil supply port 34a, a second inlet port 34b, a second outlet port 34c, a recovery port 34d and a second tank port 34e in that order from one side of the end section on the lower side in Fig. 9. When the second boom slide 42B moves along the axial direction, the connection state of the second pump oil supply port 34a and the second tank port 34e is switched with respect to the second inlet port 34b and the second outlet port 34c.

[0028] In particular, when the second boom valve 42B is in a neutral position, both the second inlet port 34b and the second outlet port 34c are in a state in which they are disconnected from the second pump oil supply port 34a, the recovery port 34d, and the second tank port 34e. When the second boom valve 42B moves downwards from the neutral position into Fig. 9 moves (to the right side in Fig. 1) The second outlet port 34c is connected to the recovery port 34d and the second tank port 34e, while the second inlet port 34b and the second pump oil supply port 34a remain in a separate state. When the second boom slide 42B moves upwards from the neutral position into Fig. 9 moves (to the left side in Fig. 1) the second outlet port 34c and the recovery port 34d remain in a separate state, while the second inlet port 34b and the second pump oil supply port 34a are in a state in which they are connected to each other.

[0029] Both the second inlet port 34b and the second outlet port 34c are connected to the bottom chamber 22 of the boom hydraulic cylinder 20 via a bottom oil channel (second oil channel) 47A. A load check valve 47Aa, which allows oil to flow only to the bottom chamber 22, is provided on the bottom oil channel 47A, which extends from the second inlet port 34b to the bottom chamber 22. As shown in Fig. As illustrated in Figures 3 to 6 and 9, the bottom oil channel 47A includes a radial bottom oil channel section 47A1, which is provided along the radial direction of the second cantilever valve hole 34 from the second inlet port 34b and the second outlet port 34c, and an axial bottom oil channel section (second oil channel section) 47A2, which is provided parallel to the axial direction of the second cantilever valve hole 34, such that it extends from an end section of the radial bottom oil channel section 47A1 to the front surface of the valve main body 30a. The axial bottom oil channel section 47A2 is located below the axial rod oil channel section 47B2 and is provided side by side with the second cantilever valve hole 34 in a left-right direction. The second pump oil supply port 34a is connected to the second supply oil channel 3B via the branch supply oil channel 48, and the second tank port 34e is connected to the tank oil channel 4 via the drain oil channel 49.

[0030] As in the Fig. As illustrated in Figures 3 to 6 and 10, the recovery port 34d of the second cantilever valve hole 34 is connected to the axial rod oil channel section 47B2 of the rod oil channel 47B via a recovery oil channel 46B provided on the valve main body 30a. The recovery oil channel 46B is arranged to slope upwards from the recovery port 34d in a direction that gradually approaches the axial rod oil channel section 47B2 and is connected to the rod oil channel 47B at a section downstream of the load check valve 47Aa. The recovery oil channel 46B is provided with a recovery check valve 46Ba that allows oil to pass only from the recovery port 34d to the rod oil channel 47B.

[0031] As from the Fig. 8 and Fig. As can be seen in Figure 9, each of the four slides 41A, 41B, 42A, and 42B is provided with a neutral spring 80 and a pressure chamber 81 at both of its end sections. The neutral spring 80 serves to hold each of the slides 41A, 41B, 42A, and 42B in a neutral position. The pressure chambers 81 accommodate the end sections of the slides 41A, 41B, 42A, and 42B and are filled with oil. Although not illustrated in the drawings, a pilot oil channel for applying a pilot pressure, which is supplied by an actuating valve, is individually connected to each of the pressure chambers 81. When the pilot pressure output according to the actuation of the actuating valve is exerted on the pressure chambers 81 via the pilot oil channels, the slides 41A, 41B, 42A and 42B are pressed in an axial direction and the slides 41A, 41B, 42A and 42B can be moved against the spring forces of the neutral springs 80.When the pilot pressure exerted on the pressure chambers 81 is removed, the slides 41A, 41B, 42A, and 42B are returned to their respective neutral positions by the spring forces of the neutral springs 80. In the present embodiment, an arm actuation valve is provided such that the two arm slides 41A and 41B move together in the same direction. Similarly, the two cantilever slides 42A and 42B are configured to move together in the same direction when a cantilever actuation valve is actuated.

[0032] In the hydraulic drive circuit configured as described above, as in Fig. As illustrated in Figure 1, when the arm slides 41A and 41B are in the neutral position, the first inlet port 31b, the first outlet port 31c, the second inlet port 32b, and the second outlet port 32c are all in a separate state. Therefore, no oil flows to the rod chamber 11 and the bottom chamber 12 of the arm hydraulic cylinder 10, and an actuating rod 14 is held in its current position relative to a cylinder main body 13.

[0033] When the arm sliders 41A and 41B are moved to the right from this state by actuating the actuating valve, Fig. When the first hydraulic cylinder 10 is moved, the oil supplied by the first hydraulic pump 1A to the first supply oil channel 3A is fed via the branch supply oil channel 44, the second pump oil supply port 32a of the second arm valve 41B, the second supply port 32b, and the rod oil channel 43B to the rod chamber 11 of the arm hydraulic cylinder 10. Simultaneously, the oil in the bottom chamber 12 is discharged into the tank T via the bottom oil channel 43A, the first outlet port 31c of the first arm valve 41A, the first tank port 31d, and the drain oil channel 45. Accordingly, in the working machine, the actuating rod 14 moves backward relative to the cylinder body 13 of the arm hydraulic cylinder 10, thereby enabling a tilting operation of the arm AM.

[0034] If, on the other hand, the arm sliders 41A and 41B are moved to the left by actuating the actuating valve in Fig. When the first hydraulic cylinder 10 is moved, the oil supplied by the first hydraulic pump 1A to the first supply oil channel 3A is fed via the branch supply oil channel 44, the first pump oil supply port 31a of the first arm valve 41A, the first inlet port 31b, and the bottom oil channel 43A of the bottom chamber 12 of the arm hydraulic cylinder 10. Simultaneously, the oil in the rod chamber 11 is discharged into the tank T via the rod oil channel 43B, the second outlet port 32c of the second arm valve 41B, the second tank port 32e, and the drain oil channel 45. Accordingly, in the working machine, the actuating rod 14 moves forward relative to the cylinder body 13 of the arm hydraulic cylinder 10, thereby enabling the lifting operation of the arm AM to be carried out.

[0035] Similarly, when the boom slides 42A and 42B are in the neutral position, the first inlet port 33b, the first outlet port 33c, the second inlet port 34b, and the second outlet port 34c are all in a separated state. Therefore, no oil flows to the rod chamber 21 and the bottom chamber 22 of the boom hydraulic cylinder 20, and an actuating rod 24 is held in its current position relative to a cylinder main body 23.

[0036] When the boom slides 42A and 42B are moved to the left from this state by actuating the actuating valve Fig. When the second hydraulic pump 1B is moved, the oil supplied by the second hydraulic pump 1B to the second supply oil channel 3B is fed via the branch supply oil channel 48, the second pump oil supply port 34a of the second boom valve 42B, the second inlet port 34b, and the bottom oil channel 47A of the bottom chamber 22 of the boom hydraulic cylinder 20. Simultaneously, the oil in the rod chamber 21 is discharged into the tank T via the rod oil channel 47B, the first outlet port 33c of the first boom valve 42A, the first tank port 33d, and the drain oil channel 49. Accordingly, on the working machine, the actuating rod 24 moves forward relative to the cylinder body 23 of the boom hydraulic cylinder 20, thereby enabling a lifting operation of the boom BM.

[0037] If, on the other hand, the boom slides 42A and 42B are moved to the right by actuating the actuating valve Fig. When the second hydraulic pump 1B is moved, the oil supplied by the second hydraulic supply channel 3B is fed through the branch supply channel 48, the first pump supply port 33a of the first boom valve 42A, the first inlet port 33b, and the rod oil channel 47B of the rod chamber 21 of the boom hydraulic cylinder 20. Simultaneously, the oil in the bottom chamber 22 is discharged into the tank T via the bottom oil channel 47A, the second outlet port 34c of the second boom valve 42B, the second tank port 34e, and the drain oil channel 49. Accordingly, on the working machine, the actuating rod 24 moves rearward relative to the main cylinder body 23 of the boom hydraulic cylinder 20, thereby lowering the boom BM.

[0038] In the hydraulic valve device 30 described above, when the arm sliders 41A and 41B move to the left, Fig. When the rod 14 moves forward, the recovery port 32d is in a state where it is connected to the second drain port 32c. Therefore, the oil discharged from the rod chamber 11 is routed through the rod oil channel 43B, the second drain port 32c, the recovery port 32d, the recovery oil channel 46A, and the recovery check valve 46Aa. This oil is supplied to the bottom chamber 12 in addition to the oil from the first hydraulic pump 1A. Accordingly, the actuating rod 14 can be moved forward without creating a vacuum in the bottom chamber 12, and the arm AM's extension operation can be carried out quickly. When the pressure in the bottom chamber 12 becomes equal to or higher than the pressure in the rod chamber 11, the recovery check valve 46Aa is held in a closed position, and the oil from the rod chamber 11 is discharged into the tank T.

[0039] Similarly, if the boom sliders 42A and 42B move to the right in Fig. When the operating rod 24 moves, the recovery port 34d is in a state where it is connected to the second outlet port 34c. Therefore, the oil discharged from the bottom chamber 22 is routed through the bottom oil channel 47A, the second outlet port 34c, the recovery port 34d, the recovery oil channel 46B, and the recovery check valve 46Ba. This oil is supplied to the rod chamber 21 in addition to the oil from the second hydraulic pump 1B. Consequently, the operating rod 24 can be moved backward without creating a vacuum in the rod chamber 21, and the lowering process of the boom BM can be carried out quickly. When the pressure in the bottom chamber 22 becomes equal to or higher than the pressure in the rod chamber 21, the recovery check valve 46Ba is held in a closed position, and the oil from the rod chamber 21 is discharged into the tank T.

[0040] Furthermore, as described above, in the arm direction switching valve 2A, the recovery oil channel 46A can be provided with a shortest path length by linearly connecting the second arm slide hole 32 and the bottom oil channel 43A (the axial bottom oil channel section 43A2), which are provided side by side. In the boom direction switching valve 2B, the recovery oil channel 46B can be provided with a shortest path length by linearly connecting the second boom slide hole 34 and the rod oil channel 47B (the axial rod oil channel section 47B2), which are provided side by side. This ensures that even if a large cross-sectional area is provided for each of the recovery oil channels 46A and 46B, it is not possible for the size of the valve main body 30a to increase or for any strength issues to arise.This also offers the advantage that oil can be efficiently recovered while suppressing pressure loss, and fuel efficiency can be improved.

[0041] The embodiment described above illustrates, by way of example, the hydraulic valve device that controls the oil supply to the arm hydraulic cylinder and the boom hydraulic cylinder of the machine, but it is also applicable to other hydraulic cylinders. In this case, it is not necessary to control a multitude of hydraulic cylinders; a single hydraulic cylinder can also be controlled.

[0042] In the arm direction switching valve 2A, the first arm slide 41A and the axial rod oil channel section 43B2 are provided side by side parallel to the axial bottom oil channel section 43A2 of the bottom oil channel 43A; however, it is sufficient that the second arm slide 41B (the first arm slide hole 32) is provided side by side with the axial bottom oil channel section 43A2. Similarly, in the boom direction switching valve 2B, it is sufficient that the second boom slide 42B (the second boom slide hole 34) is provided side by side with the axial rod oil channel section 47B2 of the rod oil channel 47B.

[0043] Furthermore, in the embodiment described above, the two arm sliders 41A and 41B are configured to move together in the same direction, and the two boom sliders 42A and 42B are configured to move together in the same direction, but the present invention is not limited to this. For example, in the arm hydraulic cylinder 10, only the second slider 41B can move to the left. Fig. 1. When the first slide 41A is in the neutral position, and the recovery port 32d may be in a state where it is connected to the second outlet port 32c, no oil is supplied to the arm hydraulic cylinder 10 from the first hydraulic pump 1A. The oil discharged from the rod chamber 11 is fed to the bottom chamber 12 via the recovery oil channel 46A. Accordingly, in the working machine, the actuating rod 14 moves forward relative to the cylinder body 13 of the arm hydraulic cylinder 10, thus enabling the lifting operation of the arm AM to be carried out.

[0044] Similarly, on the boom hydraulic cylinder 20, only the second slide 42B can move to the right. Fig.1. When the first slide 42A is in the neutral position, and the recovery port 34d may be in a state where it is connected to the second outlet port 34c, no oil is supplied to the boom hydraulic cylinder 20 from the second hydraulic pump 1B. The oil discharged from the bottom chamber 22 is supplied to the rod 21 via the recovery oil channel 46B. Accordingly, on the working machine, the actuating rod 24 moves rearward relative to the cylinder body 23 of the boom hydraulic cylinder 20, thereby enabling the lowering operation of the boom BM. Reference symbol list 1A, 1B Hydraulic pump 10 arm hydraulic cylinders 11 Rod chamber (second oil chamber) 12 Bottom chamber (first oil chamber) 20 boom hydraulic cylinders 21 Rod chamber (first oil chamber) 22 Bottom chamber (second oil chamber) 30 Hydraulic valve device 30a Valve body 31 First arm slide hole (first slide hole) 31a First pump oil supply connection 31b First inlet connection 31c First drain connection 31d First tank connection 32 Second arm slide hole (second slide hole) 32a Second pump oil supply connection 32b Second inlet connection 32c Second drain connection 32d recovery connection 32e Second tank connection 33 First cantilever gate hole (first gate hole) 33a First pump oil supply connection 33b First inlet connection 33c First drain connection 33d First tank connection 34 Second cantilever gate hole (second gate hole) 34a Second pump oil supply connection 34b Second inlet connection 34c Second drain connection 34d Recovery connection 34e Second tank connection 41A First arm slider (first slider) 41B Second arm slider (second slider) 42A First cantilever gate (first gate) 42B Second cantilever slide (second slide) 43A Bottom oil channel (first oil channel) 43A2 Axial bottom oil channel section (first oil channel section) 43B Rod oil channel (second oil channel) 43B2 Axial rod oil channel section (second oil channel) 46A Recovery oil channel 46B Recovery Oil Channel 47A Bottom oil channel (second oil channel) 47A2 Axial bottom oil channel section (second oil channel) 47B Rod oil channel (first oil channel) 47B2 Axial rod oil channel section (first oil channel section) AM Arm BM outrigger T Tank QUOTES INCLUDED IN THE DESCRIPTION

[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0000] JP 08-100803 A

[0003]

Claims

[1] Hydraulic valve device, characterized by , that: a valve body comprising a first slide that controls the oil supply to a first oil chamber of a hydraulic cylinder, and a second slide that controls the oil supply to a second oil chamber of the hydraulic cylinder; a first valve hole that accommodates the first valve, with a first pump oil supply port connected to a hydraulic pump, a first inlet port and a first outlet port connected to the first oil chamber via a first oil channel, and a first tank port connected to a tank; a second valve hole that accommodates the second valve, with a second pump oil supply port connected to the hydraulic pump, a second inlet port and a second outlet port connected to the second oil chamber via a second oil channel, and a second tank port connected to the tank; the first oil channel includes a first oil channel section that is provided parallel to an axial direction of the second slide hole and is arranged side by side with the second slide hole; the second valve hole is provided with a recovery port and a recovery oil channel is provided between the recovery port and the first oil channel section, which allows the passage of oil from the recovery port to the first oil channel section; and The recovery port is connected to the second outlet port when the oil is discharged from the second oil chamber. [2] Hydraulic valve device according to claim 1, wherein the valve body is provided with the first slide hole and the second slide hole, which are arranged side by side in a state in which the central axes of the first slide hole and the second slide hole are parallel to each other, and the second oil channel includes a second oil channel section that is provided parallel to an axial direction of the first slide hole and is arranged side by side with the first slide hole. [3] Hydraulic valve device according to claim 1, wherein the first oil channel is connected to a bottom chamber of an arm hydraulic cylinder which drives an arm of a working machine, and the second oil channel is connected to a rod chamber of the arm hydraulic cylinder. [4] Hydraulic valve device according to claim 1, wherein the first oil channel is connected to a rod chamber of a boom hydraulic cylinder which drives a boom of a working machine, and the second oil channel is connected to a bottom chamber of the boom hydraulic cylinder.

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