JPH0425603A - Stack type hydraulic control valve - Google Patents

Abstract

PURPOSE:To decrease the cost by forming of the hydraulic control valve in the title a communication valve into an internal pilot type having pressure reducing function in which a pressure reducting valve is incorporated within a spool. CONSTITUTION:When a section valve E for arm is operated so as to actuate an arm during running, the pressured oil flowing through a neutral passage 22 on the inlet side flows into actuator ports 18a, 18b because it is switched from the neutral state by movement of a spool 19. A signal passage port 14 is moved following the movement of the spool 19, as well to be in the intercept state from the fixed side signal passage port, and a raised pilot pressure is loaded onto a communication valve 32 and a pressure reducing valve 56 in a running section valve D through an actuating signal passage port 15. The chuck valve 51 of a section valve 1 for running among a second direction switching valve group 4 is pushed up by the oil pressure of a second hydraulic pump 2, and the pressured oil of the first and the second hydraulic pumps 1, 2 flows in conflux into section valves D, I for running because a communicating passage 25' is communicated with a communication passage 25.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a stack type hydraulic control valve device that is installed in a traveling hydraulic machine such as a hydraulic excavator and is suitable for controlling a plurality of hydraulic actuators in a related manner. It is something.

[Conventional technology and its technical issues]

In a traveling hydraulic machine, such as a hydraulic excavator, a rotating body operated by a swing motor is provided on a traveling body such as a crawler driven by a traveling motor, and a boom that can freely rotate by a boom cylinder is mounted on this rotating body. The boom is equipped with an arm that can be moved up and down with an arm cylinder.
Furthermore, it is common that the arm is provided with a packet that can be raised and lowered by a packet cylinder. As a hydraulic control system for such a hydraulic actuator, a two-pump system is often adopted due to its linearity and the advantage that when the arm cylinder and packet cylinder are operated simultaneously, they can move independently of each other regardless of the load.

In this two-pump system, the first hydraulic pump is generally connected to a first directional valve group consisting of a plurality of directional valves, and the second hydraulic pump is connected to a second directional valve group consisting of a plurality of directional valves. Connected to the valve group. The first directional valve group includes, for example, a running cloth switching valve, a packet switching valve, and a boom I monthly switching valve, and the second directional valve group includes, for example, a running motor and a swing switching valve. , an arm switching valve, and a boom switching valve.

Further, the plurality of switching valves are generally configured as monoblock type or stack type multiple control valves.

Such multiple control valves supply the necessary amount of pressure oil to the left and right travel motors when the front working equipment such as a swing, boom, arm, or packet and the travel motor are operated simultaneously, thereby ensuring good straight-line performance. It is necessary to be able to secure it. In addition to this, when operating multiple front working machines at the same time, it is possible to accurately adjust the balance of the amount of hydraulic fluid to each actuator (parallel passage and tandem passage are well combined and connected via a throttle). It is necessary to have the following functions:

Furthermore, it is desired that the device has the above functions, has good sealing properties, is small and compact, does not take up much space, and is inexpensive.

However, until now, there has been no practical control valve that can satisfy the above requirements. That is, as a control valve for controlling a hydraulic excavator,
No. 263710, Japanese Patent Application Laid-Open No. 63-83405,
JP-A-63-34304, JP-A-63-2199
No. 05 is known.

However, these are mainly hydraulic circuits for controlling the arm and the simultaneous operation of the arm and rotation, and specifically,
One direction switching valve group was provided with a directional switching valve for merging, and by operating this switching valve, the pressure oil from the first hydraulic pump and the second hydraulic pump was combined and supplied to the arm switching valve. . Therefore, it has not been possible to solve problems caused by simultaneous operation of the travel motor and other actuators.

In other words, when a front work equipment such as an arm is moved while traveling, a large amount of pressure oil is taken up by the arm cylinder due to the characteristics of the hydraulic circuit, and this causes a shortage of pressure oil to the travel motor in the same group as the arm cylinder, causing the actual machine to malfunction. The problem of curve progression could not be resolved.

As a countermeasure for this, it is necessary to communicate the switching valve for traveling, but in the past, the only communication mechanism for this was to install external piping or solenoid valves on the mother machine, which increased costs and There was a problem that the effective space of When another actuator is operated, the signal automatically merges the pressure oil from both the first and second hydraulic pumps into the travel switching valve without using external piping or solenoid valves. This can be achieved without using any external special pump for the pressure signal.

It is an object of the present invention to provide a stack type hydraulic control device that can be taken out from a hydraulic oil circuit and is advantageous in terms of cost reduction and space saving in a mother machine.

In order to achieve the above object, the present invention includes a first directional valve group connected to a first hydraulic pump and a second directional valve group connected to a second hydraulic pump. 1・
In a hydraulic control valve device of the type in which the second directional switching valve group is configured by stacking a plurality of section valves each including one for traveling, the following configuration is adopted.

Each section valve is connected to a pair of actuator boats, a bridge passage located inside of this and connected to and disconnected from the actuator port by a spool, and a return tank boat located outside of the actuator port and below the spool. In addition to having a continuous tank passage and neutral passages on the inlet side and the 8-port side that are located inside the bridge passage and communicated and blocked by the spool, it also has a communication passage near the bridge passage, and has a section valve other than the traveling section valve. Each of the section valves has a signal passage hole passing through the valve body so as to communicate with each other when the spool is in a neutral state, while the section valve for both travels has a signal passage hole around the spool at a position corresponding to the signal passage hole.
An annular signal groove is provided that always connects upstream and downstream regardless of the position of the spool.

The valve body of one traveling section valve is provided with a spool and a spring offset type communication valve incorporating a pressure reducing valve in the spool, and the connection plate of the directional control valve group to which this traveling section valve belongs or the adjacent The valve body is provided with a passage connecting the most upstream side of the signal passage hole and the actuation signal passage hole that reaches the actuation side of the communication valve.

〔Example〕

Embodiments of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 shows an example of the hydraulic circuit of a hydraulic excavator obtained using the stack type hydraulic control valve device according to the present invention, FIG. 2 shows the entire hydraulic control valve device of the present invention, and FIGS.
Figure 6 shows the structure of each section valve.

In FIG. 1, 1 is a first hydraulic pump, and 2 is a second hydraulic pump, which are coaxially driven by the engine of the mother machine or the like.

3 is a first directional valve group connected to the first hydraulic pump l. In this embodiment, a connection plate A, a swing section valve B, a travel section valve, and an arm section valve E are arranged from upstream to downstream.

4 is a second directional valve group connected to the second hydraulic pump 2. In this embodiment, from upstream to downstream, a connection play section valve ■, a boom section valve J, and a packet section valve K are arranged, and the first directional control valve is connected via a sub-plate G. It is in contact with the arm section valve E of group 3. The first of them
- The second directional control valve groups 3 and 4 are integrally tightened by a plurality of stud bolts 6. Next, the mechanism of each valve will be explained.

[About connection plate A]

The connection plate A of the first directional valve group 3 is connected to the third
As shown in FIG. The connection plate A has a main body 7 formed with a pump boat P that communicates with the feed passage 8 in the intermediate portion, and a reverse bridge-shaped tank port T1 that connects with the tank passage 9 on the lower side of the feed passage 8. A pump passage 10 that reaches the mating surface 100 is perpendicularly bored in the P unit, and relief valves 11 are inserted in a cross pattern in the back side of the tank port T□ and the pump boat P, and the secondary side is opened. Hole 110 communicates with the tank port tee.

The feed passage 8 communicating with the pump boat P1 has a chamber extending in the opposite direction to the tank port T0, and a hole 250 is opened from there toward the mating surface 100, and a throttle 251 is formed in this hole 250. Check valve 252 equipped with
and a built-in spring 253. Note that this hole and check valve mechanism do not necessarily need to be provided in the section plate A, but may be provided in an adjacent valve, that is, in this example, the swing section valve. In this case as well, it is preferable to provide it on the left mating surface in FIG. 1 from the viewpoint of stackability.

Further, the mating surface 100 lacks a signal boat S for connecting a signal passage hole 14, which will be described later, to an actuation signal passage hole 15 that reaches the actuating side of the communication valve. In this embodiment, it is a counterbore hole.

The feed passage 8, tank passage 9, pump passage 10, and counterbore hole S are arranged in a concentrated manner in the inner region to the extent that the strength of the main body 7 is not impaired, and the mating surface 100 has the passages and passage holes S. One O-ring 16 is attached so as to be taken inside.

[Swivel section valve B]

5 and 5a show the pivoting section valve B in its neutral state. This section valve B basically has 6 points and 3
It is a position switching valve, and a pair of actuator ports 18a and 18b are formed in the main body 17, and a spool 19 is slidably provided perpendicular to these ports, and in this embodiment, the spool 19 is operated by a hydraulic pilot type. It is now possible to do so.

The main body 17 includes the actuator port 18a.

A bridge passage 20 having a gate shape is located inside the passage 18b.
Further, a reverse-opening tank passage 21 is formed outside the actuator ports 18a and 18b. Further, in the spool hole portion inside the bridge passage 20, there is an inlet side neutral passage 22 in the center, and an outlet side neutral passage 23a on both sides thereof.

23b is formed.

The bridge passage 20 and the left and right actuator ports 1
8a, 18b and the tank passage 21 are switched by a rod section and a throttle provided on the spool 19 when the spool 19 slides, and an inlet side neutral passage 22 and an outlet side neutral passage 23 are switched.
a and 23b are configured to communicate and be cut off at a central land provided on the spool 19. Said tank passage 2
A return tank boat 24 is formed below the spool 19 and in communication with the tank passage 9 of the connection plate A.

In addition, the entrance side neutral passage 22 and the left exit side neutral passage 23
a is provided in a positional relationship that communicates with the feed passage 8 of the connection plate A.

Such a valve structure is similar to a conventional stack valve of this type, but in the present invention, a communication passage extending in a direction perpendicular to the bridge passage 20 and reaching the mating surface 100 is provided near the ceiling of the bridge passage 20. A passage 25 is provided through it, and one opening of the communication passage 25 communicates with the communication passage 25 via a check valve with a throttle provided on the mating surface 100 of the connection plate A.

Further, a pump passage 10 reaching the mating surface 100 is formed at the same position as the pump passage 10 of the connection plate A, and this pump passage 1o is connected to the bridge passage 20 by a vertical hole 26 opened above the main body 17. A parallel load check valve 27 is inserted into the vertical hole 26,
The valve is opened by the pressure of the hydraulic oil flowing through the pump passage 10, allowing the bridge passage 20 and the pump passage 1o to communicate with each other.

Furthermore, between the communication passage 1Ii 25 and the pump passage 1o, especially in the upper part of the inlet side neutral passage 22, a through hole 28 for mounting a tandem load check valve is formed so as to open into the mating surface 100.

This through hole 28 is closed by a plug 29 as shown in FIG. 10a.

Further, between the communication passage 25 and the spool hole, there is provided an actuation signal passage hole 15 which matches a counterbore S formed in the connection plate A. Also, at a position orthogonal to the spool hole, a signal passage hole 14 that matches the counterbore hole S of the connection plate A, as shown in FIG. 5a, is provided.
is drilled in the signal passage hole 1 in the spool 19 in a neutral state.
4, a narrow diameter portion 141 is formed to form an annular groove between the spool hole and the spool hole. Note that the signal port S does not necessarily need to be provided in the section plate A, and may be provided in an adjacent section valve, in this example a swing section valve.

The swing section valve B also has one O-ring 16 attached to the mating surface 100, and inside this O-ring 16 there is a pump passage, neutral passages 22, 23a on the inlet side and 8-port side,
23b, a communication passage 25, a through hole 28, a signal passage hole 14, and an actuation signal passage hole 15 are arranged.

In addition, actuator port 1 of swing section valve B
8a and 18b are connected to a swing motor M1 as shown in FIG.

[Regarding the traveling section valve] Next, FIGS. 6 and 7 show the traveling section valve. This traveling section valve has a basic configuration, namely actuator boats 18a and 18b, except that the spool 19 is manually operated.

Spool 19. Bridge passage 20, tank passage 21, entrance side. The neutral passages 22, 23a, 23b and the tank boat 24 on the outlet side are the same as the swing section valve B described above. Therefore, only the same reference numerals are shown and the explanation will be omitted.

In this traveling section valve, a communication passage 25 and an actuation signal passage hole 15 are provided through the main body 30 at the same positions as those of the turning section valve B, but the communication passage 25 opens on the upper surface of the main body. The difference is that the vertical hole 31 communicates with the actuation signal passage hole 15. A communication valve 32 consisting of an internal pilot spring offset type two-position switching valve is inserted into the vertical hole 31 to block and communicate the bridge passage 20 and the communication passage 25. The communication valve 32 includes a spool 32a, a pressure reducing valve 56 built into the spool 32a, and a cap 32c surrounding the spool portion protruding from the vertical hole 31.

To be more specific, first, as shown in FIG. 6a, the spool 32a has a tip land portion 320 that fits into the vertical hole portion 310 below the communication passage, and the communication passage 25 and the bridge passage 20.
A rear end land portion 321 that fits into the vertical hole portion 311 between them, and a rod portion 322 that connects both land portions 320 and 321.
have.

The spool 32a has a cylindrical shape, that is, a screw hole 323, a spool storage hole 324, and an offset hole 325 that opens from the bottom of the spool storage hole 324 to the top of the spool are arranged in succession from the bottom end. There is.

A spring 56b and a shaft-shaped pressure reducing valve body 56a biased by the spring 56b are inserted into the spool storage hole 324 from the back side.
is installed internally, and a plug 56c screwed into the screw hole 323 prevents the pressure reducing valve body 56a from being received.

The cap 32c is fitted onto the main body 30, and inside the cap 32c, pressure oil in the actuation signal passage hole 15 acting on the plug 56c or the tip land portion 320 urges the spool 32a toward the valve closing side until a predetermined pressure is reached. The spring 32b is indicated. A chamber 31 housing the spring 32b
2 has an offset signal passage hole 3 whose one end reaches the section chamber 312 and whose other end reaches the mating surface with the arm section valve E.
5 is drilled. In this embodiment, the offset signal passage hole 35 reaches the sub-plate G, as shown in FIG. 1, and is connected to the tank boat here. Of course, the present invention is not limited to this, and the offset signal passage hole 35 is provided in the section valves of the second directional valve group 4 such as J,
It may extend from I to section plate H, and may be connected to the end of signal passage hole 14' shown in FIG. 1 in section plate H.

As shown in FIG. 6a, the plug 56c has a through hole 560 that communicates with the actuation signal passage hole 15, and the pressure reducing valve main body 56a has a guide hole 5 that always communicates with the through hole 560 at one end.
61 is bored, and the inner part of the guide hole 561 branches in the radial direction and reaches a ring groove 562 on the outer periphery.

On the other hand, the area of the rod portion 322 of the spool 32a normally communicates with the ring groove 562, but the pressure reducing valve body 56b slides in the spool storage hole 324 against the bias of the spring 56b due to the differential pressure. A radial hole 327 is formed in such a manner that communication is sometimes interrupted.

A pump passage 10 reaching a mating surface 100 is formed in this traveling section valve at the same position as the turning section valve B, and this pump passage 10 is equipped with a parallel load check valve 27. The vertical hole 26 communicates with the bridge passage 20, and the valve body 27a of the parallel load check valve 27 is provided with a throttle 270.

Further, between the pump passage 1o and the communication passage 25, a through hole 28 that opens to the mating surface 100 is formed at the same position as the turning section valve B, and this through hole 28 is formed as shown in FIG. It communicates with the entrance-side neutral passage 22 and the bridge passage 2o via a communication hole 33 bent in the direction of the arrow.

A cap-shaped tandem load check valve 34 is inserted into the through hole 28, as shown in FIG. 10, and is urged toward the valve closing side by a spring 34a and a washer 34b. This structure is a tandem load check valve 3.
4 can be assembled using the mating surface 100 as a stopper, so there is no need for a plug or female thread machining for attaching it, and since the through hole 28 is surrounded by one large O-ring 16, there is no need for a special sealing member. You get the benefit of having one.

The main body 30 also has a signal passage hole 1 extending to the mating surface on the same axis as the signal passage M114 of the swing section valve B.
4 is drilled. This signal passage hole 14 is not drilled in the spool 19 as shown in FIG. 7, but its tip reaches a ring groove 142 formed in the spool hole. Therefore,
From the signal passage 14 of the turning section valve B to the signal passage hole 1
4, the pressure oil flowing through 4 is always connected to 7 outlet port 1 of this traveling section valve regardless of the position of spool 19.
8a and 18b are the traveling hydraulic motor M2 as shown in FIG.
connected to. Note that one O-ring 16 is attached to the mating surface 100 of the main body 30, and a pump passage 10, a signal passage hole 14, and an operation signal passage hole 15 are provided inside this O-ring 16.
, neutral passages 22, 23a, 23b on the inlet side and outlet side, tank boats 24, 25, and a through hole 28 are arranged.

Since this configuration is the same for each subsequent section valve, the explanation will be omitted hereafter and only the reference numerals will be shown.

[About arm section valve E]

8 and 9 illustrate an arm section valve E. FIG. This section valve also has the same basic configuration as the section valve described above, including a pair of actuator boats 18a provided on the main body 38.

18b is connected to the arm cylinder SL2 as shown in FIG.

The arm section valve E has a communication passage 25 penetrating therethrough at the same position as the communication passage 25 in the traveling section valve, and a through hole 28 formed at the same position as the first through hole 28, and a mating surface. A tandem load check valve 34 with 100 as a stopper surface is attached.

In the section valve E of this embodiment, the bridge passage 20 is not continuous in a bridge shape, but the upper end side is vertically shifted in phase as shown in FIG.

In other words, there is a discrepancy so that the right end is higher than the left end. A bent communication path 3 connected to the through hole 28
3 communicates with the staggered end 20a on the right side (upper side) 9, and the pump passage 10 at the same position as the travel section valve has only the upstream side reaching the mating surface as shown in Fig. 9. It is a blind hole, and in front of the bottom of the hole there is a pixel difference shaped end 20.
A vertical hole 26 is formed passing through a and 20b, into which a parallel load check valve 27 is inserted.

The valve body 27a of the parallel load check valve 27 has a fixed throttle. Although the configuration is arbitrary, in this embodiment, a two-way slotted part 271 for throttling is formed on the outer periphery of the valve body 27a, and the two staggered ends 20a, 20b are always connected by this two-way slotted part 271. It communicates.

Further, at a position perpendicular to the axis of the spool 19, a signal passage hole 1 is provided in a relationship that matches that of the traveling section valve.
4 is drilled. The configuration of this signal passage hole 14 is the same as that of the swing section valve B described above. A pore 140 crosses the spool 19 at right angles. On the other hand, the arm section valve E is not provided with the operation signal passage hole 15, and therefore the operation signal passage hole 15 of the travel section valve is stopped by the mating surface.

Further, as a new boat, this arm section valve E has a merging port hole 36 formed in the mating surface of the lower part of the left outlet side neutral passage 23a. This merging port hole 36 is located inside the O-ring 16, so no special seal is required.

If you do not want the merging port hole 36 to merge with another section, use a drill to drill a through hole that reaches both mating surfaces, and if you want to merge as in this example,
A counterbore hole 37 is formed in the mating surface so as to span the outlet side neutral passage 23a and the inlet side neutral passage 22 for connection.

In addition, this arm section valve E has actuator ports 18a and 18b on the left and right sides of the main body 38, and a tank i.
A relief valve 39a that connects the circuit 21.

39b is inserted.

[About sub-plate G]

11 and 12 show the sub-plate G. FIG. 11111 shows a cross section of a portion close to the mating surface side with the packet section valve, and FIG. 12 shows a cross section of a portion close to the mating surface side with the arm section valve E.

In the main body 42 of this sub-plate G, a tank port 24, a pump passage 10', a communication passage 251, a merging boat hole 36, and a signal passage hole 14 reach both mating surfaces at the same positions as those of the arm section valve E. It is installed like this.

The pump boat 10' is sealed by the mating surface of the arm section valve E, and the merging port hole 36 is sealed by the packet section valve. Incidentally, the pump port 10' does not necessarily have to be provided on the sub-plate G, and it is of course possible to end it with a section valve for a packet.

In this sub-plate G, recesses 43' and 43 are formed with a required depth from both mating surfaces within the region surrounded by the O-ring. The recesses 43' and 43 are blocked by a wall and are in a non-communicating relationship. A part of the recess 43' on the side of the arm section valve E communicates with the tank port 24, and the recess 43' on the side of the packet section valve communicates with the tank port 2.
It is separated from 4.

A drain passage hole 35 is bored in the body 42 on the outside of the O-ring 16 in the same position as the arm section valve E, and a vertical hole 45 whose upper end is closed is bored in the body 42. A portion thereof communicates with the drain passage hole 35, and the lower end of the vertical hole 45 communicates with the recess 43' through a bag-shaped horizontal hole 46. Therefore, the communication valve 32 of the traveling section valve
The drain oil passes through the offset signal passage hole 35 of the arm section valve E, reaches the sub-plate G, and flows into the tank port 24 through the vertical hole 45, the horizontal hole 46, and the recess 43'.

On the other hand, a recess 43 adjacent to the packet section valve
has a branching recess 44 at its lower part, the branching recess 44 communicates with the merging port hole 36, and the merging port hole 36 matches the merging port hole 36 of the arm section valve E, and the recess 44 communicates with the merging port hole 36. Since 43 is located at a position corresponding to the neutral passage on the inlet side and outlet side of the packet section valve, the pressure oils of the first hydraulic pump 1 and the second hydraulic pump 2 join together.

Next, the second direction switching valve group 3 will be explained.

[About connection plate H]

First, as shown in FIG. 13, the connection plate H has a pump boat P2 connected to the second hydraulic pump P2 to the main body 47, and a reverse bridge-shaped tank port T leading to the tank.
2 is provided, the pump boat P2 communicates with a large feed passage 8' in the center, and the tank port T2 communicates with a tank passage 9' reaching the mating surface in the center, and the pump boat P2 communicates with a tank passage 9' that reaches the mating surface in the center. It is connected to pump boat P2 via 11'.

A tank passage 9' is connected to the tank port T2 from the inlet.
A signal passage hole 14' reaching the mating surface is bored in the area between. The feed passage 8', the tank passage 9' and the signal passage hole 14' are provided inside one O-ring 16.

[About the traveling section valve]

The running section valve is shown in FIG. Its basic configuration is the same as the traveling section valve in the first directional valve group 3 described earlier, and the actuator ports 18a, 18b are connected to the traveling hydraulic motor M2' as shown in FIG. . Between the bridge passage 20' and the spool hole, from the left side, a pump passage 10'', a through hole 28', and a communication passage 25 are connected, similar to the section valve described above.
The pump passage 10' and the communication passage 25 are sealed on one side by the mating surface of the connection plate H.

The pump passage 10' is blocked from communicating with the bridge passage 20'' by a plug 49 inserted into a vertical hole 26 formed in the upper end of the main body 48 due to the positional relationship of the section valve in the directional valve group.

On the other hand, in this example, the plug 29 and the load check valve 34 are not fitted into the through hole 28', and it remains a mere hole. The lower end of a vertical hole 50 extending longitudinally through the bridge passage 20' and reaching the upper surface of the main body communicates with the communication passage 25, and a check valve 51 for preventing backflow from the communication passage 25 is inserted into the vertical hole 50.

The main body 48 of the traveling section valve is provided with a signal passage hole 14'' at a position perpendicular to the spool 19' and aligned with that of the connection plate H.
is drilled. The tip of the signal passage hole 14' is a ring groove 142 that surrounds the spool in the same way as the traveling section valve of the first directional valve group 3, and the spool 19
Hydraulic pressure can be circulated from the sub-plate side regardless of the position of .

[About boom section valve J]

FIG. 15 shows the section valve J for the boom. In this embodiment, the first directional valve group 3 is not provided with a section valve for the boom L, but of course, for example, the section valve for the swing B
It may be installed between the travel section valve and the travel section valve, and may be used for boom I or boom ■.

This boom section valve J has the same basic configuration as the swing section valve B described above. That is, between the bridge passage 20' and the spool 19', there are the pump passage 10', the through hole 28' and the communication passage 25 in a relationship matching that of the running section valve, and below the spool 19' there is a tank boat. 24' and a signal passage hole 14' passing through the body 52 and the spool at right angles to the axial direction.

A tandem load check valve 34' with a mating surface as a stopper is provided in the through hole 28', and a tandem load check valve 34' is connected to the pump passage 10 from the top surface of the body.
A parallel load check valve 2 is installed in the vertical hole 26 leading to the
7' are attached respectively.

However, in this section valve J, there are relief valves 53a on the left and right sides of the main body 52 that connect the actuator ports 18a', 18b' and the tank passage 21'.

53b is inserted, and the pump passage 10' and the inlet side neutral passage 22' communicate with each other through a connection port 54 that crosses the communication hole 33''.The actuator ports 18a' and 18b' They are each connected to the cylinder CLI.If the first directional valve group 3 is provided with another boom section valve, it goes without saying that it is connected to the pipe line corresponding to the actuator port of this section valve.

[Regarding the section valve K for packets] FIG. 16 shows the section valve K for packets. The main body 55 of this section valve also has a pump passage 10' in a positional relationship that matches the section valve J for the boom L and the sub-plate G.
A communication passage 25', a tank passage 24', an inlet side neutral passage 2', an outlet side neutral passage 23a' and 23b', and a signal passage hole 14' are provided through the pump passage 10'' and a communication passage 25'. A through hole 28' is formed therebetween, and in this example the through hole 28' remains a hole.

This section valve has a vertical hole 26' opening from the pump passage 101 to the top surface of the main body, and a parallel load check valve 27' having the same configuration as the boom L section valve J.
is inserted. Further, in this section valve, a merging port hole 36' is formed below the inlet side neutral passage 22' and the outlet side neutral passage 238', similar to the arm section valve E (FIG. 8). Counterbore hole 37 on mating surface
'' is not processed, the entrance side neutral passage 22'
The outlet side neutral passage 23a' does not communicate with the outlet side neutral passage 23a'. That is, the merging port hole 36' is simply a through hole and sealed at the mating surface.

It should be noted that not only the arrangement, valve structure, and operating mechanism of each section valve described above, but also the name of each section valve itself is an example, and is not limited to the embodiment.

[Effect of the embodiment]

When the first hydraulic pump and the second hydraulic pump are driven, the oil discharged from the first hydraulic pump 1 passes from the pump port P1 of the connection plate A to the first directional valve group 3 through the feed passage 8 and the pump passage 10. The oil discharged from the second hydraulic pump 2 is sent from the pump port P8 of the connection plate H to the second directional valve group 4 through the sending passage 8'.

In the neutral state shown in FIG.
It passes through the inlet-side neutral passage 22 and the outlet-side neutral passage 23a, which are installed at the same position in the arm section valve E, and flows through the recess 43' formed in the sub-plate G to the tank port 24.

In addition, the hydraulic oil that has passed through the pump passage 10 flows through the pump passage 10 that penetrates each section valve from the swing section valve B to the arm section valve E,
The arm section valve E reaches the parallel load check valve 27, and when this valve is pushed up, the flow rate is throttled through the fixed throttle (in this example, the two-way section on the outer periphery) 271, and one side of the bridge passage 20 is reached. It flows into the staggered end 20a on the upper side forming the inlet side neutral passage j! It joins with the hydraulic oil that has flowed in through 22.

On the other hand, the hydraulic oil of the second hydraulic pump 2 that has passed through the feed passage 8' is supplied to the traveling section valve J, the boom section valve J,
It flows through the inlet side neutral passage 22' and the outlet side neutral passages 23a' and 23b', which are provided through the packet section valve K, and flows into the recess 43 provided in the sub-plate G. The six merging port holes 36 that flow into the merging port 6 36 via the branch recess 44 that is connected to the recess 43 are formed as through holes in the sub-plate G and the arm section valve E. Hydraulic oil flows through each of these section valves. Since the merging port hole 36 of the arm section valve E is connected to the inlet side neutral passage 22 and the outlet side neutral passage 23a through a counterbore hole 37 as shown in FIG. Directional switching valve group 3, 4
The hydraulic fluids of the two are combined.

Further, the hydraulic oil flowing through the neutral passage 22 on the inlet side of the first directional control valve group 3 is transferred to the bridge passage by opening the tandem load check valve 34 provided in the travel section valve shown in Fig. 6. 20, the communication valve 32 blocks communication between the communication passage 25 and the bridge passage 820. On the other hand,
The hydraulic oil passing through the neutral passage 22' on the inlet side of the second directional control valve group 4 is transferred to the bridge passage 20' by opening the tandem load check valve 34' of the traveling section valve in FIG.
However, the check valve 51 blocks communication between the communication passage 25' and the bridge passage 20'.

On the other hand, in the section plate A, a part of the pressure oil that has flowed into the pump passage 10 passes through the branch passage 250, the flow rate is restricted by the throttle 251, and the check valve 252 is opened to open the turning section valve B. The communication passage 25 is connected to the communication valve 32 in the traveling section valve.
has reached.

In the present invention, a pilot hydraulic pressure is created by using the pressure oil passing through the communication passage 25 without using a dedicated signal pump for operating the communication valve 32, and two hydraulic pressures are applied to the traveling section valve I. This is to merge the pump's pressure oil.

That is, the signal passage hole 14 and the actuation signal passage hole 15 communicate with each other via the signal port S of the connection plate A in FIG.
9. Full-section valves B and C are installed perpendicularly to the axis of 19'.

D, E, F, G, J, I signal passage holes 14°14'
through to the tank port T, at the connection plate H of the terminal. In addition, in the two traveling section valves I, the water flows to the downstream section valves via ring grooves 142, 142'.

On the other hand, the signal port S of the connection plate A is bored at the same position as the operation signal passage hole 15 of the turning section valve B, and as shown in FIG. plug 56c and the pressure reducing valve main body 56a. As described above, the pressure oil in the communication passage 25 is supplied to the spool 3 from the radial hole 327 as shown in FIG. 6a.
2a, and flows to the actuation signal passage hole 15 via the guide hole 561 of the pressure reducing valve body 56a. The pressure oil that has passed through the guide hole 561 acts on the lower surface of the pressure reducing valve body 56a, and when the pressure of the pressure oil is too high, the pressure reducing valve body 56a is lifted against the spring 56b, and the line between the guide hole 561 and the radial hole 327 is Cut off communication. Therefore, the operating pressure of the communication valve 32 can be reduced to a safe pilot pressure of about 20 kg/aJ, for example.

If the travel section valve I is operated in this state, the spools 19 and 19' are moved to switch, and the pressure oil from the first hydraulic pump and the second hydraulic pump is transferred to the actuator port 18a.

Travel motor M2 via 18b, 18a', 18b'
．． Each is supplied to M2', and the mother machine runs. Even if the spool 19, 19' moves, the signal passage hole 14, 14' of the running section valve I always communicates between the upstream and downstream through the ring grooves 142, 142' formed in the spool hole, so the pilot signal is not transmitted. is not blocked in any way.

During such traveling, when the arm control valve E is operated to move the front working machine, for example, the arm, which is controlled by the first directional control valve group 3, the pressure oil flowing through the inlet side neutral passage 22 is The actuator port 1 is switched from the neutral state by the movement of the spool 19.
8a and 18b. This reduces the amount of oil supplied from the first hydraulic pump 1 to the travel motor Ml. However, in the present invention, the spool 1 of the section valve
With the movement of the signal passage hole 9, the signal passage hole 14 also moves, and is in a state of being cut off from the fixed side signal passage hole of the main body.

As a result, pressure builds up in the signal passage hole system, and increased pilot pressure is applied to the communication valve 32 and the pressure reducing valve 56 in the travel section valve via the actuation signal passage hole 15 communicating therewith.

That is, since the pilot pressure acts on the lower surface of the pressure reducing valve body 56a in FIG. 6a, the pressure reducing valve body 56a lifts against the spring 56b, and the ring groove 562 is isolated from the radial hole 372.

This cuts the edge between the communication passage 25 and the actuation signal passage hole 15. In addition, the pilot pressure acts on the plug 56,
The tip land portion 320 is strongly pressed. When the pressure exceeds the spring force of the setting spring 32b, the spool 32a of the communication valve 32 lifts, thereby connecting the communication JI 25 and the bridge passage 20 via the rod portion 322.
It's connected.

At this time, the chuck valve 51 of the traveling section valve I in the second directional switching valve group 4 is pushed up (opened) by the pressure oil of the second hydraulic pump 2, and the communication passage 25' is connected to the communication passage 2.
5, the two traveling section valves, I
Pressure oil from the first and second hydraulic pumps 1 and 2 flows together. Therefore, even if the arm or the like is moved while the mother machine is running, the required amount of oil is secured, and the same amount of pressure oil is supplied to the travel section valve I, so that the mother machine can move straight ahead smoothly.

In the arm section valve E, the bridge passages 20 are separated in a staggered manner as shown in FIG. A recess 271 is formed, so that the hydraulic pressure in the pump passage 10 is constantly throttled and flows into the bridge passage 20. For this reason, spool 19
When moved to the left in FIG. 8, the entrance side neutral passage 22
The oil pushes up the check valve 27 in the closed state from the upper bridge passage section, flows to the lower parallel feeder section, and flows out from the actuator port 18a. On the other hand, when the spool 19 is moved to the right, the oil in the inlet side neutral passage 22 flows from the upper bridge passage to the actuator bolt 18b, and at the same time, the oil in the pump passage 10 is throttled by the fixed throttle 271 and flows toward the upper side. flows into the bridge passage.

All section valves B, D, E, I, J and connection plates A, H each contain various ports in one O-ring 16. That is, an inlet side neutral passage 22 for unloading, a tank passage 24 for return, and a pump passage 10 for parallel. Communication passage for communication valve 25. A signal core (signal passage hole) 14 for operating a communication valve, a merging passage 3 for connecting tandem passages
6 and a load check valve 34 for the tandem passage are centrally arranged inside one O-ring 16, and the ports between the section valves are metal sealed by the mating surface 100. Therefore, there is no need to provide any special sealing member, the whole can be made compact, and the space of the mother machine can be used effectively.

〔Effect of the invention〕

According to the present invention described above, in addition to the freedom of arrangement due to the stack type, the communication valve is attached to the traveling section valve, and the operation signal of the front work equipment is transmitted through the spool through hole and the ring groove of the spool hole. Therefore, by simultaneously operating the traveling and front work equipment, the mother machine can be moved forward at low cost without the need for expensive equipment such as solenoid valves. Since it is an internal pilot type with a pressure reducing function that has a pressure reducing valve built into the spool, there is no need for a dedicated signal pump such as an external gear pump, which has the excellent effect of lowering costs. is obtained.

[Brief explanation of drawings]

Fig. 1 is a circuit diagram showing an example of a hydraulic circuit to which a stack type hydraulic control valve device according to the present invention is applied, Fig. 2 is a plan view of the hydraulic control valve device of the present invention in Fig. 1, and Fig. 3 is a first direction direction. Sectional view of the connection plate in the switching valve group, No. 4
The figure is also a partially cutaway plan view, FIG. 5 is a sectional view of the swing section valve, and FIG. 5a is a cross sectional view showing a part thereof.
Figure 6 is a sectional view of the running section valve, Figure 6a is the 6th section valve.
A partially enlarged view of the figure, FIG. 7 is also a partially cutaway plan view,
Fig. 8 is a sectional view of the arm section valve, Fig. 9 is a partially cutaway plan view thereof, Fig. 10 is a sectional view of each section valve cut at the center of the tandem passage, and Fig. 10a is a sectional view of the section valve for the arm.
11 is a sectional view of the sub-plate on the second directional valve group side; FIG. 12 is a sectional view of the sub-plate on the first directional valve group side; FIG. 13 is a sectional view of the connection plate in the second directional valve group, FIG. 14 is a sectional view of the traveling section valve, and FIG. 15 is a sectional view of the boom section valve.
FIG. 16 is a sectional view of the packet section valve. A... Connection plate, B... Swinging section valve, D... Traveling section valve, E... Arm section valve, G... Sub plate, H... Connection plate, engineering/・・Traveling section valve, J・
... section valve for boom, K ... section valve for packet, 1 ... first hydraulic pump, 2 ... second hydraulic pump, 3 ... first directional valve group, 4 ... third Two-way switching valve group, 10.10'...Pump passage, 14.14'
... Signal passage hole, 15.15'... Operation signal passage hole, 16... O ring, 18a, 18b, 18a',
18b'...actuator port, 19.19'.
...Spool, 20.20'...Bridge passage, 20
a, 20b...Staggered ends, 21...Tank passage, 22...Inlet side neutral passage, 23a, 23b...Outlet side neutral passage. 24...Tank port, 25, 25'...Communication passage, 28...Through hole, 32...Communication valve, 32a...Spool, 56...Pressure reducing valve

Claims (1)

[Scope of Claims] A first directional valve group connected to a first hydraulic pump and a second directional valve group connected to a second hydraulic pump; In a hydraulic control valve system in which the directional control valve group is composed of a stack of multiple section valves, each including one for traveling, each section valve is located inside a pair of actuator ports and connected to a spool. A bridge passage that connects and shuts off the actuator port, a tank passage that connects to the return tank port located outside the actuator port and below the spool, and a tank passage that connects and shuts off the spool that is located inside the bridge passage. In addition to having neutral passages on the inlet side and outlet side where the spool is in a neutral state, it also has a communication passage near the bridge passage, and further has a communication passage so that each section valve other than the traveling section valve communicates with each other when the spool is in a neutral state. While having a signal passage hole penetrating the valve body, the double running section valve has an annular signal groove around the spool at a position corresponding to the signal passage hole that always connects the upstream and downstream sides regardless of the position of the spool. and a spring offset type communication valve having a spool that connects and disconnects the bridge passage and the communication passage and a pressure reducing valve built into the spool is provided on the valve body of one of the traveling section valves. A connection plate or an adjacent valve body of the directional control valve group to which the valve belongs is provided with a passage connecting the most upstream of the signal passage hole and the actuation signal passage hole leading to the actuation side of the communication valve. Stack type hydraulic control valve device.