JPH0835501A - Multiple directional control valve device - Google Patents

Abstract

PURPOSE:To determine uniform dimensions by providing a part of functions required for the operation of a pressure source of one directional control valve in another directional control valve to increase the degree of freedom of the dimension setting of the respective directional control valve. CONSTITUTION:The directional control valves A, B each having the different operating characteristic of a pressure source are provided in a row and at the same time a part 4 of functions 3, 4 required for the operation of the pressure source of one directional control valve B is provided in the other directional control valve A.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a multiple directional valve device for forming a hydraulic circuit of a construction machine such as a shovel.

[0002]

2. Description of the Related Art A variety of directional control valves are used in construction machines, one of which is a directional control valve for operating a boom. The direction switching valve is provided with an overload relief valve for preventing the pipe from bursting when a large load is applied to the boom and a lock valve for preventing the boom from coming down.

In the conventional directional control valve, an actual flat opening 1-158 is used.
There is one described in Japanese Patent No. 803. This type of directional control valve uses non-leak valves 8A, 8A and 8A to prevent leakage of the hydraulic pilot valve 2 at the neutral position of the spool 3.
B (the lock valve of the present invention), and the overload relief valve 7 is superposed on the non-leak valves 8A and 8B.
A and 7B are provided.

Further, the construction machine has a directional control valve for controlling traveling, and since the directional control valve is additionally provided with a counterbalance valve and an overload relief valve in a hydraulic motor and the like, The valve itself does not have an overload relief valve or lock valve.

When used in a hydraulic circuit of a construction machine or the like, the directional switching valve for boom and the directional switching valve for traveling are continuously provided to form a multiple directional switching valve device.

[0006]

However, in the multi-directional directional control valve device of the prior art, the boom directional control valve is provided with the overload relief valves 7A and 7B on the non-leak valves 8A and 8A. However, there has been a problem that the size of the directional control valve becomes large and a dimensional difference occurs in the height direction between the directional control valve and the traveling directional control valve. As a result, when the multiple directional switching valve device is configured by connecting the directional switching valves in series, the multiple directional switching valve device also becomes large in space,
When arranging the multiple directional control valve device just below the driver's seat, there is a problem that the height of the construction machine becomes high.

The present invention has been made in order to solve such a problem, and a part of the function required for operating the pressure source of one directional control valve is provided in the other directional control valve. It is an object of the present invention to provide a multiple directional switching valve device capable of uniformly determining dimensions by increasing the degree of freedom in setting the dimensions of each directional switching valve.

[0008]

In order to solve the above problems, the multiple directional control valve device of the present invention is characterized in that, in claim 1, a plurality of directional control valves for switching the path of the pressure supplied from the pressure source are connected in series. In a multi-directional directional control valve device configured to be installed, a directional control valve having different operating characteristics is connected in series to the pressure source, and one of the functions required for one directional control valve is provided in another direction. It is characterized by being provided in the switching valve.

According to a second aspect of the present invention, in the multi-directional directional control valve device according to the first aspect, the directional control valves arranged in a row operate the spool to switch the oil path of the pressure source. A second direction switching valve having a valve and an overload relief valve that operates the spool to switch the oil path of the pressure source and prevents the spool from being in the neutral position. The overload relief valve of the switching valve is provided in the first directional switching valve.

According to a third aspect of the present invention, in the second aspect, the overload relief valve is connected to a passage branched between the pressure source and the lock valve of the second directional control valve, and the oil of the pressure source is connected. The pressure is returned to the tank via the drain passages of the overload relief valve and the second directional control valve.

According to a fourth aspect, in the third or fourth aspect, the first directional control valve and the second directional control valve are integrally arranged in a block body.

[0012]

According to the multiple directional control valve device of the present invention as described above, in claim 1 or 2, some of the functions necessary for operating the pressure source of one directional control valve are Since the directional control valve is provided, the degree of freedom in setting the dimensions of each directional control valve is increased, and the shape of each directional control valve can be made substantially the same.

According to the present invention, the overload relief valve is connected to a passage branched from between the pressure source and the lock valve of the second directional control valve, and the oil pressure of the pressure source is passed through the overload relief valve and the drain passage. Since it has a structure in which it can be returned to the tank, the overload relief valve can be provided in the first directional control valve without any trouble by sharing it with the drain which is conventionally used.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A multiple directional control valve device according to an embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a plan view showing the whole of the multiple direction switching valve device according to this embodiment, FIG. 2 is a side view of the multiple direction switching valve device according to this embodiment, and FIG. 3 is a second direction of this embodiment. 5 is a sectional view taken along the line AA of FIG. 1 showing the configuration of the switching valve, FIG. 4 is a sectional view taken along the line CC of FIG. 1 showing the configuration of the first directional switching valve of the present embodiment,
FIG. 3 is a cross-sectional view taken along line BB in FIG. 2 showing the arrangement state of the bidirectional switching valves of this embodiment.

In FIGS. 1 and 2, reference numeral 1 denotes a multiple directional control valve device, which is provided on a block body 2 formed in a rectangular cube, for example, two first and second directional control valves A and B.
Are arranged in parallel.

The second directional control valve B (for boom) has a boom lock valve 3, and the first directional control valve A (for traveling) has an overload relief valve 4 as shown in FIG. Two
As shown in, the block body 2 is arranged at a position substantially the same as the boom lock valve 3 in the height direction, and the first direction switching valve A switches the path of the pressure supplied from the hydraulic pump 2A. The second directional control valve B switches the path of the pressure supplied from the hydraulic pump 2A, and at the same time, hydraulic fluid is supplied from the tank passage TA through the gap between the spool 10 and the block body 2 which will be described in detail later. It has a function of a lock valve 3 for preventing the boom from descending due to a leak and a function of an overload relief valve 4 for preventing the pipe from bursting when a large load is applied to the boom.

This directional control valve B has a structure as shown in FIG. 3. The structure of the second directional control valve B will be described below with reference to FIG. 3. In FIG. 2, 10 is a spool. Yes, it is slidably fitted in the spool hole 11 provided in the block body 2, and both ends 10 of the spool 10 are
The cover bodies 12 and 13 fixed to the block body 2 on the side of a and 10b respectively project into the pilot chambers 14 and 15 and one end is biased by the main spring 16 and is normally set to the neutral position as shown in FIG. ing.

Pilot ports 17 and 18 which open to the pilot chambers 14 and 15 are formed in the cover bodies 12 and 13, and the pilot port 17 is connected to a hydraulic pilot valve 19 through a pipe.

Further, the pilot port 18 is connected to a hydraulic pilot valve 19 via a pipe 21, and by operating this hydraulic pilot valve 19, it is connected to the tank T. This hydraulic pilot valve 1
9 is configured as a touch lever type remote control valve, and is connected to the remote control pump 19A and the tank T. By operating this lever 19B, the remote control pump 19A
The hydraulic pressure supplied to the pilot port 18 is returned to the tank T while the hydraulic pressure supplied to the pilot port 17 is connected to the tank 20 by communicating with the piping 20.

The block body 2 has low-pressure passages 22, 22 which open at both ends of the spool hole 11 of the spool 10 and communicate with the tank passage TA, and a central passage 23 at the center.
But the feeder passages 24 and 24 opening into the spool bore 1 1 at each position between the low-pressure passage 22 and the central passage 23, respectively, are parallel decoupled formed in the extending direction of the spool bore 11 There is.

The feeder passage 24 has a check valve G-
The hydraulic pump 2A serving as a pressure source is connected via a passage 24A, and the central passages 23, 23 are also connected to the hydraulic pump 2A via a passage 23A.

Further, the block body 2 is provided with a cylinder port 25 connected to one chamber of the boom operating cylinder C (actuator) (not shown) and a cylinder port 26 connected to the other chamber. The cylinder ports 25, 26 are located between the low pressure passages 22, 22 and the feeder passages 24, 24, respectively, and
It is communicated with the spool hole 11 through the cylinder passages 27 and 28 that open at 1.

The spool 10 is formed with end stems 10c and 10d for partitioning the liquid chambers a and b between the cylinder passages 27 and 28 at the neutral position, and operates the lever 19B of the hydraulic pilot valve 19. Then, when the hydraulic pressure is introduced into the pilot port 17 and the spool 10 is moved to the cover body 13 side, the cylinder passage 28 and the low pressure passage 22 are communicated with each other, and the cylinder passage 27 and the feeder passage 24 are communicated with each other, and the hydraulic pump Oil pressure from 21A is in passage 2
4A-Check valve G-Feeder passage 24-Liquid chamber a-Cylinder passage 27 and cylinder port 25 are supplied to one chamber of the cylinder C, and the hydraulic pressure in the other chamber of the cylinder C is applied to the cylinder port 26-. Lock valve 3-
It is returned to the tank passage TA through the cylinder passage 28-liquid chamber b-low pressure passage 22.

When the lever 19B of the hydraulic pilot valve 19 is operated in the opposite manner to the above to introduce the hydraulic pressure into the pilot port 18 and move the spool 10 to the cover body 12 side, The low-pressure passage 22, the cylinder passage 28, and the feeder passage 24 are communicated with each other, and the hydraulic pressure of the hydraulic pump 2A is transferred from the passage 28-the cylinder port 26 to the cylinder C in a route opposite to the above.
Is supplied to the other chamber of the cylinder C, and the hydraulic pressure in one chamber of the cylinder C is applied to the cylinder port 25-cylinder passage 2
7 and the low pressure passage 22 to be returned to the tank passage TA.

Between the cylinder passage 28 which connects the cylinder port 26 and the spool hole 11, the boom is inserted into the poppet hole 29 formed by the block body 2 and the cover body 13 communicating with the cylinder passage 28. A lock valve 3 is arranged. The poppet hole 29 is a stepped hole in which a small-diameter hole portion 29A, a medium-diameter hole portion 29B, and a large-diameter hole portion 29C whose diameter gradually increases in the direction from the block body 2 to the cover body 13 are continuously formed. This small diameter hole 29A
The cylinder passage 2 is provided on each of the end and the inner peripheral surface of the medium diameter hole portion 29B.
8 is open.

A poppet 31 is slidably fitted in the medium-diameter hole portion 29B, and a recess 32 is formed inside the poppet 31 so as to open toward the large-diameter hole portion 29C. Further, the poppet 31 is formed with a through hole 33 that extends in the radial direction toward the head 31B side protruding from the main body 31A to the small diameter hole portion 29A and opens into the cylinder passage 28. It communicates with the recess 32 through a through hole 34 that opens in the through hole 33 and extends in the axial direction.

In the recess 32 of the poppet 31, a filter member 35, a connecting member 36, and a stopper member 37 are arranged in this order from the bottom toward the opening side.
By screwing 6 and the stop member 37 into the recess 32,
A filter material 35 is engaged with this bottom. The connecting member 36 is formed with a throttle hole 38 which communicates with the through hole 34 via the filter material 35, and the stop member 37 is formed with a through hole 39 which communicates the throttle hole 38 with the recess 32.

Further, a spring 41 is stretched between the stopper member 37 and the spring receiving member 40 which is fitted in the large diameter hole portion 29C and the medium diameter hole portion 29B, and the spring force of the spring 41 causes the poppet to spring. 31 is urged toward the small diameter hole portion 29A,
The head portion 31B is slidably fitted in the small diameter hole portion 29A, and the tip of the main body 31A is seated on the valve material 42 formed at the opening side end of the small diameter hole portion 29A, and the cylinder port 2
6 and the spool hole 11 are shut off.

The cover body 13 is formed with an inlet port 44 connected to the hydraulic pilot 19 via a pipe 43 branched from the pipe 20 connected to the hydraulic pilot 19.
4 is communicated with a cylinder hole 45 opening to the inlet port 44 and the pilot port 18. The cylinder hole 45 is a stepped hole in which a large diameter hole 45A and a small diameter hole 45B are continuously reduced in diameter in a direction from the inlet port 44 to the pilot port 18, and the small diameter hole 45B of the cylinder hole 45 is formed. A piston 46 is slidably fitted in the.

This piston 46 has a large diameter hole 45 from the tip.
It has a shaft portion 47 projecting to A, and a spring bearing member 48 is screwed to the tip of this shaft portion 47. It is urged toward the inlet port 44 side by the spring force of the spring 50 stretched between the spring receiving member 49 engaged with the bottom of the large diameter hole 45A. Further, the piston 46 is formed with a connecting hole 51 which is open at an end on the pilot port 18 side and extends in the axial direction. The connecting hole 51 is formed through through holes 52 and 52 which are opened on an outer peripheral surface of the piston 46. It communicates with the small diameter hole 45B of the cylinder hole 45.

The small diameter hole 45B of the cylinder hole 45 is
The through hole 53 formed in the cover body 13 and the through hole 40 </ b> A of the spring receiving member 40 in the poppet hole 29 communicate with the medium diameter hole portion 29 </ b> B (recess 32) of the poppet hole 29.
As a result, the piston 46 is moved toward the pilot port 18 side against the spring force of the spring 50, and the through hole 52 faces the through hole 53, whereby the medium diameter hole portion 29B of the poppet hole 29 and the through hole. 40A-through hole 53-through hole 52, 52
-Communicated with the pilot port 18 via the connection hole 51.

In the cylinder passage 28 between the cylinder port 26 and the poppet hole 31, as shown in FIG. 4, a vertical hole communicating with the overload relief valve 4 arranged in the first directional control valve A which will be described later in detail. 80 is formed by opening. Further, the overload relief valve 4 is also arranged in the lateral hole communicating with the cylinder passage 27. Next, referring to FIG. 5, the first directional control valve A in which the overload relief valve 4 is arranged will be described. In FIG. 5, the directional control valve A becomes the second directional control valve B described above. It is provided in parallel in the longitudinal direction of the block body 2.

Reference numeral 60 denotes a spool, which is slidably fitted in a spool hole 61 provided in the block body 2 and is fixed to the block body 2 at both ends 60a and 60b of the spool 60. Pilot room 64,
65, one end of which is biased by the main spring 66, and is normally set to the neutral position as shown in FIG.

Pilot ports 67 and 68 which open to the pilot chambers 64 and 65 are formed in the cover bodies 62 and 63, and the pilot port 67 is connected to the hydraulic pilot valve 19 through a pipe 69. Further, the pilot port 68 is the hydraulic pilot valve 19
Is connected to a hydraulic pilot valve 119 equivalent to

In the block body 2, low-pressure passages 71, 71 which open at both ends of the spool hole 61 of the spool 60 and communicate with the drain TA, a central passage 23 in the center, and the low-pressure passages 71, 71 and the center are provided. Passages 73 that open to the spool holes 61 at respective positions between the passages 23 and the passages 23 are divided and formed parallel to the extending direction of the spool holes 61. Then, the passage 73 is a check valve G1-the passage 73-.
It is connected to the hydraulic pump 2A via a central passage 23.

Further, the block body 2 is provided with a cylinder port 74 connected to one chamber of the motor C1 for running operation.
And a cylinder port 75 connected to the chamber on the other side. The cylinder ports 74, 75 are located between the low pressure passages 71, 71 and the central passage 23, respectively, and open in the spool hole 61. It communicates with the spool hole 61 via 76 and 77.

The spool 60 is formed with end stems 60c and 60d for partitioning the liquid chambers a and b between the cylinder passages 76 and 77 at the neutral position, and operates the lever 119B of the hydraulic pilot valve 119. Then, when hydraulic pressure is introduced into the pilot port 67 and the spool 60 is moved to the cover body 63 side, the cylinder passage 77 and the low pressure passage 71 are communicated with each other, and the cylinder passage 76 and the central passage 23 are communicated with each other, and the hydraulic pump Oil from the central passage 23-
The liquid C is supplied to the motor C1 through the liquid chamber a-the cylinder passage 76 and the cylinder port 74, and the motor C1 is supplied.
Oil is returned to the tank passage TA through the cylinder port 75, the cylinder passage 77, the liquid chamber b, and the low pressure passage 71.

Further, the lever 119B of the hydraulic pilot valve 119 is operated in the opposite manner to the above to introduce hydraulic pressure into the pilot port 68, and the spool 60 is covered with the cover body 62.
When moving to the side, the cylinder passage 76 and the low pressure passage 7
1. The cylinder passage 77 and the central passage 23 are communicated with each other, and oil is supplied from the hydraulic pump 2A to the motor C1 through the central passage 23-cylinder port 75 and the motor C1 through a route opposite to the above. Cylinder port 74
-Returned to the tank passage TA via the cylinder passage 76 and the low pressure passage 71.

Further, the block body 2 has the cover body 6
A recess 78 that opens to the end surface on the third side is formed.
The overload relief valve 4 is screwed into and attached to the inside 8. The recess 78 communicates with the vertical hole 80 via the lateral hole 79 and also communicates with the spool hole 61 via the tank passage 81.

Thus, the multiple directional control valve 1 of this embodiment is
Is configured as described above. Next, this operation will be briefly described.

First, the operation of the second directional control valve B will be described. When the spool 10 is in the neutral position, the end stems 10c and 10d of the spool 10 communicate with the cylinder passages 27 and 28. At this time, the poppet 31 of the boom lock valve 3 is seated on the valve seat 42, the divided cylinder passage 28 is blocked, and the pilot pressure is not applied to the pilot port 17. Further, the pressure from the cylinder C is applied to the cylinder ports 25 and 26, and the pressure in the cylinder port 26 is intermediate from the cylinder passage 28 through the through hole 33-filter material 35-throttle hole 38 and through hole 39. Diameter hole 29A
The medium diameter hole 29A (recess 3) flows into the (recess 32).
2) It is stored inside. Therefore, the cylinder port 28
The load pressure of the (cylinder C) is reliably maintained, and the leakage from the gap between the piston 46 and the cylinder hole 45 has a large wrap amount and a smaller diameter than the spool 10 (because only a small flow rate needs to be controlled. ,), The leakage is extremely small, which prevents the boom driven by the cylinder C from descending.

Next, the lever 19B of the hydraulic pilot valve 19 is used to move the spool 10 to the cover body 13 side.
Is operated, the pilot pressure is reduced to the pipe 20 and the pipe 43.
Through the pilot port 17 and the inlet port 44. Then, the pilot pressure introduced into the pilot port 17 enters the pilot chamber 14, and the pilot pressure presses the spool 10 toward the cover body 13 side. At the same time, due to the pilot pressure introduced into the inlet port 44, the piston 46 resists the spring force of the spring 50 and moves in the cylinder hole 45 inside the pilot port 18.
To the side, and finally to the through holes 52, 52
3 communicates with each other, so that the pressure (pressure of the cylinder C) trapped in the poppet hole 29 is the through hole 40A-the through hole 53.
The hydraulic pilot valve 19 from the pilot port 18 through the pipe 21 in the path of the through hole 52 and the connecting hole 51.
To the tank T via.

As a result, the pressure in the medium-diameter hole portion 29B in which the spring 41 is stretched is reduced, and a pressure difference is generated before and after the throttle hole 38, so that the poppet 31 resists the spring force of the spring 41 and springs. The main body 31A moves away from the valve seat 42 by moving to the receiving member 40 side. As a result, the cylinder port 26 communicates with the liquid chamber b via the cylinder passage 28.

Therefore, the return oil from the cylinder C passes through the tip of the poppet 31 and is smoothly returned to the tank T by the route of the cylinder passage 28-the liquid chamber b-the low pressure passage 22-the tank passage TA.

Next, regarding the operation of the first directional control valve A, pilot pressure is introduced from the hydraulic pilot valve 19 into the pilot ports 67 and 68, and the spool 60 is moved to the cover body 62 or 63 side. Cylinder passage 76 and high pressure passage 23, cylinder passage 77 and low pressure passage 71
By communicating with the cylinder passage 76, the motor C1, the cylinder passage 77, the low pressure passage 71, and the tank passage T.
Returned to tank T by route A.

From the cylinder C to the cylinder port 26
The pressure returned to No. 2 reaches the overload relief valve 4 through the cylinder passage 28-vertical hole 80-horizontal hole 79, but in the normal case, the relief valve 4 does not operate, and as described above, the lock valve 3 Cylinder passage 2 communicated by opening the valve
Although it is returned to the tank T via 8, when this pressure reaches a pressure higher than a predetermined value (pressure at which there is a risk of bursting the pipe or the like), the overload relief valve 4 operates and the vertical hole 80
And the tank passage 81 are communicated with each other, the pressure supplied to the overload relief valve 4 is returned to the tank T through the route of the tank passage 81, the low pressure passage 71, and the tank passage TA.

As described above, according to the multiple directional control valve device of this embodiment, the directional control valves A and B are combined into one block body 2.
In addition to the above, since the directional control valve B that requires lock control of the cylinder C has the overload relief valve 4 that is originally disposed at the position where the directional control valve A is located, this lock control is required. When the directional control valve B and the directional control valve A that does not require lock control are arranged in multiple rows, the dimensions (shapes) can be made substantially the same, and a space for installing a construction machine or the like can be saved. It is possible to reduce.

In this embodiment, the second directional control valve B and the first directional control valve A are integrally provided on the block body 2. However, the present invention is not limited to this. The directional control valve A and the directional control valve B are provided in separate blocks, and the overload relief valve 4 arranged in the directional control valve A is connected to the cylinder port 26 of the directional control valve B by piping or the like. It may be one.

Further, in the present embodiment, the block main body 2 has two directional switching valves A and B arranged therein, but the number of directional switching valves arranged in the block body 2 is limited. Instead of one, three or more may be integrally arranged in the block body 2.

[0051]

As described above, according to the multiple directional control valve device of the present invention, some of the functions required for operating the pressure source of one directional control valve are provided in the other directional control valve. As a result, the degree of freedom in setting the size of each directional control valve is increased, and the shape of each directional control valve can be made substantially the same. Therefore, the multiple switching valve device in which the directional control valves are arranged in series is downsized. This makes it possible to reduce the installation space of the multiple switching valve device of the construction machine or the like, and it can be adapted to the installation space of the construction machine or the like.

Further, according to the present invention, an overload relief valve is connected to a passage branched between the pressure source and the lock valve of the second directional control valve, and the oil pressure of the pressure source is controlled by this overload relief valve. Since it can be returned to the tank via the, the overload relief valve can be provided in the first directional control valve without any trouble.

[Brief description of drawings]

FIG. 1 is a plan view showing an entire multiple direction switching valve device according to an embodiment of the present invention.

FIG. 2 is a side view of the multiple directional control valve device in the present embodiment.

FIG. 3 is a sectional view taken along line CC of FIG. 1 showing the configuration of the second directional control valve of the present embodiment.

FIG. 4 is a cross-sectional view taken along the line AA of FIG. 1 showing the configuration of the first directional control valve of this embodiment.

FIG. 5 is a cross-sectional view taken along line BB in FIG. 2, showing the arrangement of the two-way switching valves of this embodiment.

[Explanation of symbols]

 1 Multiple directional switching valve 2 Block body 3 Lock valve 4 Overload relief valve 10, 60 Spool A First directional switching valve B Second directional switching valve C Cylinder C1 Motor T Tank TA Tank passage

Claims (4)

[Claims] 1. A multi-directional directional control valve device configured by arranging a plurality of directional control valves for switching a path of pressure supplied from a pressure source, wherein the pressure sources are connected with directional control valves having different operating characteristics. In addition to installing some of the functions required for one directional valve,
A multiple directional control valve device characterized by being provided in another directional control valve. 2. A first directional switching valve, wherein the directional switching valve connected in series operates a spool to switch an oil path of the pressure source; and a spool operates to switch an oil path of the pressure source, and A second directional control valve having a lock valve and an overload relief valve that prevent this when the spool is in the neutral position, and an overload relief valve of the second directional control valve is provided in the first directional control valve. The multiple directional switching valve device according to claim 1, wherein 3. The overload relief valve is connected to a passage branched from between the pressure source and the lock valve of the second directional control valve, and the oil pressure of the pressure source is adjusted to the overload relief valve and the second direction. 3. The multiple directional switching valve device according to claim 2, wherein the multiple directional switching valve device is returned to the tank via a drain passage of the switching valve. 4. The multiple directional switching valve device according to claim 2, wherein the first directional switching valve and the second directional switching valve are integrally arranged in a block body.