JP4897424B2 - Control valve device - Google Patents

Description

  The present invention relates to a control valve device that is provided in a construction machine such as a hydraulic excavator and is preferably used for controlling supply / discharge of pressure oil to / from a hydraulic actuator.

  Generally, in a construction machine such as a hydraulic excavator, pressure oil is supplied to and discharged from a hydraulic actuator (for example, a hydraulic motor, a hydraulic cylinder, etc.) from a hydraulic source such as a hydraulic pump. A control valve device including a control valve is provided.

  A control valve device according to this type of prior art is inserted into a valve housing provided with a spool sliding hole and a plurality of oil passages communicating with the spool sliding hole, and the spool sliding hole of the valve housing. A spool that communicates and blocks between the plurality of oil passages, and a left that forms a pilot oil chamber in the valve housing that is located on both sides in the axial direction of the spool and that drives the spool in the axial direction. , And a right lid (see, for example, Patent Document 1).

  Further, in the control valve device according to the prior art, when the spool is held at the neutral position in the spool sliding hole of the valve housing, the load pressure from the hydraulic actuator leaks (leaks) and the hydraulic actuator becomes inadvertent. In order to prevent it from moving, for example, an anti-drift valve called a fall prevention valve is provided.

  In this case, the anti-drift valve is provided in the valve housing in the middle of the actuator-side oil passage connected to the hydraulic actuator among the plurality of oil passages, and the hydraulic pressure is increased when the spool is in the neutral position. A pilot operated check valve that receives load pressure from the actuator and shuts off between the spool and the hydraulic actuator, and is provided in one of the left and right lids and is guided from the pilot oil chamber. The pilot pressure switching valve is configured to switch and control supply and stop of the load pressure (back pressure) to the pilot operated check valve by the pilot pressure applied.

JP 2003-222102 A

  By the way, in the above-described conventional technology, a pilot oil chamber for driving the spool in the axial direction and a pilot type switching valve for an anti-drift valve are provided in one of the left and right lids. . However, a pressure (load pressure from the hydraulic actuator) that is several times to several tens of times higher than the pilot pressure in the pilot oil chamber acts on the pilot type switching valve.

  For this reason, in the case of the prior art, one of the left and right lids is made of a metal material having a higher pressure resistance than the other lid (for example, a heavy iron material of cast iron). The other lid is formed of, for example, an aluminum-based lightweight material.

  However, the lid made of heavy cast iron-based material is a heavy object when assembling or maintaining the control valve device (during maintenance or inspection), and therefore it is not easy to handle and causes a reduction in overall workability. There is a problem.

  In addition, the lid made of heavy cast iron-based material has excellent pressure resistance and high strength, but when drilling oil holes, etc. in the lid using a thin drill, for example, the processing time becomes excessively long, There is a problem that not only the tool life of a drill or the like is shortened, but also a processing defect or the like is likely to occur in some cases.

  Therefore, in order to solve the above problems, the present inventors have a lid body in which the pilot oil chamber is formed on the outer surface of the valve housing, and a lid body in which a pilot-type switching valve of an anti-drift valve is incorporated. Were considered separately.

  However, in this case, the two lids are connected using a pilot pipe serving as an external pipe, and the pilot pressure from the pilot oil chamber formed in one lid body via the pilot pipe is applied to the other lid body. It is necessary to lead to a pilot type switching valve.

  For this reason, the operation | work which connects pilot piping between two cover bodies takes an effort, and the problem that the operation man-hour accompanying the assembly operation of a control valve apparatus increases arises. In addition, the connection location of the pilot pipe is likely to cause oil leakage and the like, resulting in poor workability during maintenance.

  The present invention has been made in view of the above-described problems of the prior art, and the object of the present invention is to easily guide the pilot pressure between the two lids without using a pilot pipe or the like that is an external pipe. An object of the present invention is to provide a control valve device capable of improving workability during assembly and maintenance of the device and suppressing occurrence of oil leakage and the like.

  In order to solve the above-described problems, the present invention provides a valve housing provided with a spool sliding hole and a plurality of oil passages communicating with the spool sliding hole, and is inserted into the spool sliding hole of the valve housing. A spool that communicates and blocks between a plurality of oil passages, and a left that forms a pilot oil chamber in the valve housing that is located on both sides in the axial direction of the spool and that drives the spool in the axial direction. And a control valve device including a right lid.

A feature of the configuration adopted by the invention of claim 1 is that the valve housing is provided with a separate lid body in a contact state at a position close to one of the left and right lid bodies, One lid is provided with one oil passage extending from the pilot oil chamber in the one lid toward the abutting surface side of the lid and the valve housing, and the separate lid is provided with: for guiding the pilot pressure to the separate lid body through the oil passage of the one from the pilot oil chamber of the lid body of the one, toward the said another number of cover the body abutment surface of said valve housing only set the other oil passage extending to said valve housing, said abutment surface and said one of the oil passage and the other of the one of the lid so that the oil passage communicate with each other and separate lid open a recessed portion formed as a blind hole, a closure plate for the opening side of the concave recess is closed in an oil-tight state Provided, the said closing plate, the oil hole in communication with the one of the oil passage and the other oil passages provided between the closure plate and said recessed portion, the said one oil passage of the other The one cover body and a separate cover body are in contact with the closing plate that forms the communication path including the oil hole for communicating with the oil passage and closes the opening side of the recessed portion. It lies in the fact that to that configuration and the.

  According to a second aspect of the present invention, the separate lid is formed of a material having a pressure resistance higher than that of the one lid.

According to a third aspect of the present invention, the valve housing is located in the middle of an actuator-side oil passage connected to a hydraulic actuator among the plurality of oil passages, and the hydraulic pressure when the spool is in a neutral position. A pilot operation check valve that receives a load pressure from the actuator and shuts off between the spool and the hydraulic actuator is provided, and the other lid body includes the one oil passage, the communication passage, and the pilot oil chamber. A pilot-type switching valve that shuts off the load pressure supplied to the pilot operated check valve by the pilot pressure guided through the other oil passage is provided.

  As described above, according to the first aspect of the present invention, the valve housing is provided with the separate lid body in the abutting state at a position close to one of the left and right lid bodies. The one lid body and the separate lid body can be formed using different materials (for example, a separate lid body is a heavy cast iron-based material), and has sufficient durability and pressure resistance against the load pressure of the hydraulic actuator. Performance can be imparted to a separate lid. Moreover, one lid can be formed using, for example, an aluminum-based lightweight material, and a pilot oil chamber can be formed inside the lid. Then, by forming the two lids with different materials in this way, it is possible to improve the handleability at the time of assembling and maintenance of the apparatus and improve the workability.

The one lid body is provided with one oil passage extending from the pilot oil chamber in the one lid body toward an abutting surface side of the lid body and the valve housing, and the separate lid body is provided. the, the separate lid body through the oil passage of the one from the pilot oil chamber of the lid body of the one for guiding the pilot pressure, the said another number of cover the body abutment surface of said valve housing only set the other oil passage that extends in said valve housing, said abutment surface and said one of the oil passage and the other above the oil passage so as to communicate with each other one of the cover and a separate lid A recessed portion that is open to the side and formed as a bottomed hole, and a closing plate that closes the opening side of the recessed portion in an oil-tight state. The closing plate includes the one oil passage and the other An oil hole communicating with the oil passage is provided, and the one oil passage and the other oil are provided between the recessed portion and the closing plate. Preparative forms a communication passage including the oil hole for communicating, wherein the recessed portion and the closure plate which closes the open side of said one of the lid and a separate lid you contact arrangement It is said. Therefore, by making through always communication between the oil passage and the other oil path of the one through the communication passage formed between the recessed portion closing plate, the use of the pilot piping serving as an external piping Without being able to easily connect between the pilot oil chamber and each of the oil passages through the recessed portion of the valve housing between the two lids, it is possible to suppress the occurrence of oil leakage and the like, It is possible to improve workability during assembly and maintenance of the apparatus.

  Further, according to the invention described in claim 2, since the separate lid is formed of a material having a pressure resistance higher than that of the one lid, the separate lid is made of, for example, a heavy cast iron material. By forming, sufficient durability and pressure resistance against the load pressure of the hydraulic actuator can be given to the separate lid. Further, the one lid body can be formed using, for example, an aluminum-based lightweight material, and a pilot oil chamber can be formed therein.

  According to the third aspect of the present invention, the valve housing is provided with a pilot operated check valve, and the supply and shutoff of load pressure (back pressure) to the pilot operated check valve is switched in a separate lid. Because the pilot type switching valve is provided, the pilot type switching valve is switched by the pilot pressure guided from the pilot oil chamber formed in one lid through the closing plate, the communication path between the recessed parts and the oil passage. For example, the operation of the anti-drift valve composed of a pilot operated check valve and a pilot type switching valve can be stabilized. When the spool is held in the neutral position within the spool sliding hole of the valve housing, the hydraulic actuator can be prevented from inadvertently moving due to load pressure leakage (leakage), and the operation of the hydraulic actuator is stabilized. be able to.

  Hereinafter, a case where the control valve device according to the embodiment of the present invention is applied to a control valve device for a hydraulic cylinder will be described as an example with reference to the accompanying drawings.

  Here, FIG. 1 to FIG. 8 show a first embodiment of the present invention. In the figure, reference numeral 1 denotes a hydraulic pump that constitutes a hydraulic power source together with a tank 2, and the hydraulic pump 1 is driven to rotate by a prime mover (not shown) of a hydraulic excavator, for example. It is discharged as oil.

  3 is a working hydraulic cylinder constituting a hydraulic actuator, and this hydraulic cylinder 3 constitutes, for example, a boom cylinder, an arm cylinder or a bucket cylinder provided in a working device (not shown) of a hydraulic excavator. The hydraulic cylinder 3 includes a tube 4, a piston 5, a rod 6, and the like.

  In this case, the inside of the tube 4 of the hydraulic cylinder 3 is defined by the piston 5 into two oil chambers 3 </ b> A and 3 </ b> B, and the base end side of the rod 6 is fixed to the piston 5. And the front end side of the rod 6 protrudes out of the tube 4, and is expanded and contracted by the pressure oil supplied and discharged into the tube 4.

  Reference numerals 7A and 7B denote a pair of hydraulic pipes connected to the oil chambers 3A and 3B of the hydraulic cylinder 3. The hydraulic pipes 7A and 7B are constituted by hydraulic pipes such as flexible hoses, for example. The oil passages 16A and 16B of the housing 12 are connected. The hydraulic pipes 7A and 7B supply and discharge the pressure oil from the hydraulic pump 1 to and from the oil chambers 3A and 3B of the hydraulic cylinder 3 through the directional control valves 25 and 26 described later. The rod 6 is expanded and contracted from the tube 4.

  8 is a pressure reducing valve type pilot operating valve (hereinafter referred to as an operating valve 8) for remotely operating the hydraulic cylinder 3. The operating valve 8 is provided, for example, in a driver's cab (not shown) of the hydraulic excavator. An operation lever 8A that is tilted is provided. The operation valve 8 has a pump port connected to the pilot pump 9 and a tank port connected to the tank 2. Further, the output port of the operation valve 8 is connected to pilot oil chambers 30A and 30B (36A and 36B) of a directional control valve 25 (26) to be described later via pilot pipelines 10A and 10B.

  When the operator tilts the operation lever 8A, the operation valve 8 applies a pilot pressure corresponding to the operation amount to the pilot oil chambers 30A and 30B of the direction control valve 25 (26) through the pilot pipe lines 10A and 10B. (36A, 36B). Thereby, the direction control valves 25 and 26 are switched from the neutral position (A) shown in FIG. 1 to any one of the switching positions (B) and (C).

  11 is a control valve device provided between the hydraulic pump 1, the tank 2 and the hydraulic cylinder 3. The control valve device 11 includes valve housings 12, 13, spools 27, 28, lids 29A, 29B, which will be described later. It is comprised by the below-mentioned direction control valves 25 and 26 which consist of 35A, 35B, etc., and the below-mentioned anti-drift valve 43 grade | etc.,.

  12 and 13 are valve housings constituting the valve body of the control valve device 11, and the valve housings 12 and 13 are abutted at the positions of the abutting surfaces 12A and 13A as shown in FIG. When performing, they are separated from each other at the positions of the abutting surfaces 12A and 13A. Note that the valve housings 12 and 13 may be formed in advance as an integrated body.

  The valve housings 12 and 13 are formed with spool sliding holes 14 and 15 extending leftward and rightward and spaced apart in the axial direction of the spool sliding holes 14 and 15. Oil passages 16A and 16B communicating with each other and other oil passages 17 and 18 positioned between the oil passages 16A and 16B are provided.

  Here, the oil passages 16A and 16B in the valve housings 12 and 13 constitute an oil passage on the actuator side, and are connected to the oil chambers 3A and 3B of the hydraulic cylinder 3 shown in FIG. 1 via the hydraulic lines 7A and 7B. It is what is done. The other oil passages 17 and 18 are formed in the valve housings 12 and 13 as passage holes having an inverted U shape, and the end portions located on both the left and right sides communicate with the spool sliding holes 14 and 15. is doing.

  The valve housing 12 is provided with annular oil grooves 19A, 19B on the peripheral wall side of the spool sliding hole 14 at positions outside the oil passages 16A, 16B in the axial direction. Annular oil grooves 20A and 20B are provided at positions on the outer peripheral side of the sliding hole 15 in the axial direction from the oil passages 16A and 16B. These oil grooves 19 </ b> A, 19 </ b> B, 20 </ b> A, 20 </ b> B constitute a tank side oil passage (hydraulic power source side oil passage) and are connected to the tank 2.

  Reference numeral 21 denotes a high-pressure passage provided in the valve housing 12. The high-pressure passage 21 is connected to the discharge side of the hydraulic pump 1 shown in FIG. 1 and is supplied with pressure oil from the hydraulic pump 1. A check valve 22 is provided between the high pressure passage 21 and the oil passage 17. In addition, a high-pressure passage 23 and a check valve 24 are provided on the valve housing 13 side in the same manner.

  Here, the check valves 22 and 24 allow the pressure oil to flow from the high pressure passages 21 and 23 toward the oil passages 17 and 18, and prevent reverse flow. The oil passages 17 and 18 are connected to the high-pressure passages 21 and 23 via the check valves 22 and 24 to constitute a pump-side oil passage (hydraulic source-side oil passage).

  Reference numerals 25 and 26 are directional control valves that constitute a part of the control valve device 11. The directional control valves 25 and 26 include spool sliding holes 14 and 15 of the valve housing 12, spools 27 and 28, which will be described later, and a lid. 29A, 29B, 35A, 35B, return springs 32, 38 and the like. The directional control valves 25 and 26 are pressurized oil supplied to and discharged from the oil chambers 3A and 3B of the hydraulic cylinder 3 by switching from the neutral position (A) shown in FIG. 1 to the switching positions (B) and (C). Is controlled to be switched.

  27 and 28 are spools of the direction control valves 25 and 26, and the spools 27 and 28 are inserted into the spool sliding holes 14 and 15 of the valve housing 12. The spool 27 is slidably displaced in the left and right directions in the spool sliding hole 14 in accordance with a pilot pressure supplied to pilot oil chambers 30A and 30B described later. The spool 28 is slidably displaced in the left and right directions in the spool sliding hole 15 in accordance with a pilot pressure supplied to pilot oil chambers 36A and 36B described later.

  In this case, when the spool 27 in the valve housing 12 is displaced leftward from the neutral position shown in FIG. 2, the one oil passage 16A on the actuator side communicates with the oil groove 19A on the tank side, and the other oil passage The passage 16B is communicated with the oil passage 17 (the high pressure passage 21 via the check valve 22). When the spool 27 is displaced rightward from the neutral position shown in FIG. 2, one oil passage 16A communicates with the oil passage 17 (the high pressure passage 21 via the check valve 22), and the other oil passage 16B The tank communicates with the oil groove 19B on the tank side.

  On the other hand, the spool 28 in the valve housing 13 is also slidably displaced leftward and rightward from the neutral position shown in FIG. 2 in the same manner as the spool 27 described above, so that the oil passages 16A and 16B on the actuator side are moved to the tank side. The oil grooves 20A and 20B and the oil passage 18 are selectively communicated with each other.

  29A and 29B are left and right lids that constitute the direction control valve 25 together with the spools 27 and 28, and the lids 29A and 29B are formed using, for example, an aluminum-based lightweight material. It is set sufficiently lower than the lid 41 of the above. For this reason, the lids 29A and 29B can perform hole machining, cutting, and the like relatively easily.

  Here, the lid bodies 29A and 29B are positioned on both sides of the spool sliding hole 14 in the axial direction (left and right directions) and abutted against the outer surface of the valve housing 12, and using bolts (not shown) or the like. It is detachably fixed to the outer surface of the valve housing 12. The lids 29A and 29B close the left and right ends of the spool sliding hole 14 from the outside of the valve housing 12 in an oil-tight state.

  Pilot oil chambers 30A and 30B are formed in the lid bodies 29A and 29B. The pilot oil chambers 30A and 30B are piloted through the pilot valves 10A and 10B from the operation valve 8 shown in FIG. Pressure is supplied. As a result, the spool 27 of the direction control valve 25 is slidably displaced leftward and rightward in the spool sliding hole 14 in accordance with the pilot pressure at this time.

  Here, as shown in FIGS. 3 and 4, the lid 29A has an opening end 29A1 on one side abutted against the outer surface of the valve housing 12, and a part of the opening end 29A1 is also attached to a closing plate 57 described later. It is abutted (abutted) in an oil-tight state. The pilot oil chamber 30A in the lid 29A communicates with an oil groove 56B in the recessed portion 56 via an oil passage 34, an oil hole 57B (see FIGS. 3 and 4), which will be described later. .

  Reference numeral 31 denotes a stopper shaft provided at the right end of the spool 27. The stopper shaft 31 is fixed to the spool 27 on the base end side, and the distal end side extends outward in the lid body 29A in the axial direction. The stopper shaft 31 has a function of returning the spool 27 to a neutral position via a return spring 32, which will be described later, and restricts the stroke end when the spool 27 is slid in the right direction.

  Reference numeral 32 denotes a return spring provided in the lid 29A to hold the spool 27 in a neutral position. The return spring 32 is provided on the outer peripheral side of the stopper shaft 31 via spring receivers 33A and 33B as shown in FIG. The spool 27 is always urged toward the neutral position. The return spring 32 allows the spool 27 to slide and displace in the left and right directions in FIG. 2 by elastically deforming.

34 is a small-diameter oil passage as one oil passage formed in the lid 29A, and the oil passage 34 is located outside the pilot oil chamber 30A as shown in FIG. 3 and FIG. The lid body 29A is bored so as to extend in parallel with the spring 32 and the like, and one side thereof serves as a radial hole 34A and communicates with the pilot oil chamber 30A. As shown in FIG. 4, the other side of the oil passage 34 extends toward the abutting surface between the valve housing 12 and the lid 29A (opening end 29A1), and communicates with an oil hole 57B of the closing plate 57 described later. Is.

  35A and 35B are left and right lids constituting the direction control valve 26 together with the spool 28. The lids 35A and 35B are located on both sides in the axial direction of the spool sliding hole 15 and are arranged on the outer surface of the valve housing 13. It is provided in an abutting state and closes both end sides of the spool sliding hole 15. The lids 35A and 35B are also formed using, for example, an aluminum-based lightweight material, and the pressure resistance performance is set sufficiently lower than that of the lid 41 described later.

  Here, pilot oil chambers 36A and 36B are formed in the lid bodies 35A and 35B, and the pilot oil chambers 36A and 36B are also formed in the pilot oil chambers 36A and 36B from the operation valve 8 shown in FIG. 1 via the pilot pipe lines 10A and 10B. Pilot pressure is supplied. The spool 28 of the direction control valve 26 is slidably displaced in the left and right directions in the spool sliding hole 15 according to the pilot pressure at this time.

  Reference numeral 37 denotes a stopper shaft provided at the right end portion of the spool 28. The stopper shaft 37 is fixed to the spool 28 at the base end side and extends in the lid 35A in the axial direction. The stopper shaft 37 regulates the stroke end when the spool 28 is slid and displaced in the right direction, for example.

  Reference numeral 38 denotes a return spring provided in the lid 35A for holding the spool 28 in a neutral position. The return spring 38 is provided on the outer peripheral side of the stopper shaft 37 via spring receivers 39 and 40 as shown in FIG. The spool 28 is inserted to constantly urge the spool 28 toward the neutral position and to allow the spool 28 to slide and displace in the left and right directions in FIG.

Reference numeral 41 denotes a separate lid provided in the valve housing 12 in an abutting state. The lid 41 is arranged at a position adjacent to the lid 29A of the direction control valve 25, that is, at a position close to the lid 29A. . The lid 41 is abutted against the outer surface of the valve housing 12 in the same manner as the lid 29A, and is detachably fixed to the outer surface of the valve housing 12 using a bolt (not shown) or the like. . As shown in FIGS. 3 and 4, the abutting surface side of the lid 41 is also in contact with a closing plate 57 described later in an oil-tight state.

  The lid 41 closes a later-described valve body housing hole 45 and the like from the outer surface of the valve housing 12 in an oil-tight state, and constitutes a part of the anti-drift valve 43 described later. The lid 41 is formed using, for example, a heavy cast iron material, and has sufficient durability, pressure resistance performance, etc., against the load pressure from the hydraulic cylinder 3.

  Here, as shown in FIG. 3, the lid body 41 is formed with a fitting hole 41A into which a later-described valve cylinder 51 is fitted and attached as a bottomed hole. A tank passage 41B extending in the radial direction of the fitting hole 41A and connected to the tank 2 is provided. In addition, a load pressure passage 41C that guides the load pressure of the hydraulic cylinder 3 from, for example, a passage portion that is always in communication with the hydraulic pipe 7A in the oil passage 16A opens at an intermediate portion in the axial direction (length direction) of the fitting hole 41A. Is provided.

Reference numeral 42 denotes a small-diameter oil passage as the other oil passage formed in the lid body 41. The oil passage 42 is a lid so that a position on the radially outer side of the fitting hole 41A extends in parallel with the fitting hole 41A. The body 41 is perforated. As shown in FIG. 4, one side of the oil passage 42 extends toward an abutting surface between the valve housing 12 and the lid body 41 and communicates with an oil hole 57C of a closing plate 57 described later. Further, the other side of the oil passage 42 serves as a radial hole 42A and communicates with a pilot port 51E of a valve cylinder 51 described later.

  43 is an anti-drift valve that constitutes a part of the control valve device 11 and serves as a fall prevention valve. The anti-drift valve 43 neutralizes the spools 27 and 28 in the spool sliding holes 14 and 15 of the valve housings 12 and 13. This prevents the hydraulic cylinder 3 from inadvertently moving due to leakage (leakage) of hydraulic oil (load pressure) from the oil chamber 3A of the hydraulic cylinder 3 when held in position. The anti-drift valve 43 includes a pilot operation check valve 44, which will be described later, a pilot-type switching valve 50, and the like.

  44 is a pilot operated check valve provided in the valve housing 12 in the middle of the oil passage 16A. The pilot operated check valve 44 is positioned between the spool sliding hole 14 and the hydraulic line 7A. The valve body housing hole 45 having a valve seat 45A provided in the middle of the oil passage 16A, a check valve body 46, a movable spring receiver 47, a spring 49, and the like, which will be described later, are configured.

  46 is a check valve body of the pilot operated check valve 44, and this check valve body 46 is slidably inserted into the valve body receiving hole 45 of the valve housing 12 as shown in FIG. It is composed of the body. The check valve body 46 communicates and shuts off the intermediate portion of the oil passage 16A with respect to the hydraulic pipe line 7A by being attached to and detached from the valve seat 45A.

  Reference numeral 47 denotes a movable spring receiver provided in the valve element housing hole 45 located on the back side of the check valve element 46. The movable spring receiver 47 is inserted into a later-described valve cylinder 51 as shown in FIG. A back pressure chamber 48 is formed between the hole 51B and the check valve body 46. In the back pressure chamber 48, a spring 49 is disposed between the check valve body 46 and the movable spring receiver 47 and constantly biases the check valve body 46 in the valve closing direction. ing.

  50 is a pilot type switching valve that constitutes the anti-drift valve 43 together with the pilot operated check valve 44. The pilot type switching valve 50 is provided in the lid 41 (partly in the valve housing 12) as shown in FIGS. 1), switching to either the standby position (a) or the operating position (b) shown in FIG. 1 to supply and shut off (stop) the load pressure (back pressure) to the pilot operated check valve 44. Is switched and controlled.

  As shown in FIG. 4, the pilot-type switching valve 50 is fitted in the fitting hole 41 </ b> A of the lid body 41 and is provided with a cylindrical valve cylinder 51 in which a spool sliding hole 51 </ b> A is formed on the inner peripheral side. And a small-diameter spool valve body 52 inserted into the spool sliding hole 51A of the valve cylinder 51, and a movable spring receiver 47 located on one side in the axial direction of the spool valve body 52. And a plug 54 that closes the other axial side of the valve cylinder 51.

  A pilot oil chamber 55 is formed in the valve cylinder 51 between the other axial side of the spool valve body 52 and the plug 54, and a pilot port 51E described later is formed in the pilot oil chamber 55. Pilot pressure is supplied via The spool valve body 52 in the valve cylinder 51 (spool sliding hole 51A) is displaced in the axial direction in the spool sliding hole 51A in accordance with the pilot pressure in the pilot oil chamber 55.

  An insertion hole 51B having a diameter larger than that of the spool sliding hole 51A is provided on one side of the valve cylinder 51 in the axial direction, and the inside of the insertion hole 51B is arranged coaxially with the spool sliding hole 51A. . In the insertion hole 51B of the valve cylinder 51, a movable spring receiver 47 of the pilot operation check valve 44 is inserted. Further, the valve cylinder 51 is provided with a pressure supply / discharge port 51C, a load pressure port 51D, and a pilot port 51E which are separated from each other in the axial direction of the spool sliding hole 51A.

  On the other hand, a low pressure passage 51F extending in parallel with the spool sliding hole 51A is formed in the axial direction (length direction) of the valve cylinder 51, and one side of the low pressure passage 51F is connected to the spool sliding hole 51A and the insertion hole. It communicates with the radial hole 51G at the boundary position with 51B. The other side of the low-pressure passage 51F is always in communication with the tank passage 41B of the lid body 41.

  Here, when the pilot pressure supplied to the pilot oil chamber 55 in the valve cylinder 51 is smaller than the urging force of the spring 53, the spool valve body 52 of the pilot type switching valve 50 is in the standby position (a) shown in FIG. Retained. As a result, the load pressure of the hydraulic cylinder 3 is guided to the load pressure passage 41C of the lid 41, and the back pressure of the pilot check valve 44 via the load pressure port 51D, the supply / discharge port 51C and the like shown in FIG. It is supplied to the chamber 48 and presses the check valve body 46 together with the spring 49 toward the valve seat 45A.

  As a result, the pilot operated check valve 44 receives the load pressure from the hydraulic cylinder 3 as the back pressure by the check valve body 46, and the check valve body 46 is strongly seated against the valve seat 45A. The oil passage 16A in the housing 12 is blocked at a midway position (position of the valve seat 45A), and the load pressure from the hydraulic cylinder 3 (oil chamber 3A) is leaked to the spool sliding hole 14 side of the valve housing 12. It is something to prevent.

  When the pilot pressure supplied to the pilot oil chamber 55 in the valve cylinder 51 becomes larger than the urging force of the spring 53, the spool valve body 52 slides in the left direction in FIG. As a result, the pilot-type switching valve 50 is switched from the standby position (a) shown in FIG. 1 to the operating position (b).

  For this reason, the load pressure passage 41C of the lid body 41 and the load pressure port 51D of the valve cylinder 51 are shut off from the supply / discharge port 51C by the spool valve body 52, and the back pressure chamber 48 of the pilot operated check valve 44 is The tank passage 41B communicates with the port 51C, the radial hole 51G, and the low pressure passage 51F.

  As a result, in the pilot operated check valve 44, the pressure in the back pressure chamber 48 is reduced to the tank pressure level, and the check valve body 46 is seated on the valve seat 45A only by the urging force of the spring 49. In this state, when a pressure difference larger than the urging force of the spring 49 is generated before and after the valve seat 45A in the oil passage 16A in the valve housing 12, the check valve body 46 is opened, and the oil passage 16A. The internal pressure oil (or return oil) is allowed to flow before and after the valve seat 45A.

  56 is a recessed portion provided in the valve housing 12, and the recessed portion 56 is formed by recessing the outer surface of the valve housing 12 located between the lid body 29 </ b> A and the lid body 41. As shown in FIG. 6, it is formed as a concave groove having an oval shape. That is, the recessed portion 56 is formed as a bottomed hole that opens on the abutting surface side between the lid body 29A and the lid body 41 as shown in FIG. 4, and the opening side 56A is formed as a valve as shown in FIG. An opening is formed on the outer surface of the housing 12. The recessed portion 56 is configured such that the opening side 56A is detachably closed by a closing plate 57 described later.

  In addition, an oil groove 56 </ b> B that extends in the long axis direction of the concave portion 56 having an oval shape is formed on the bottom side of the concave portion 56. The oil groove 56B is recessed in an I shape with a groove width slightly larger than the diameter of the oil holes 57B and 57C in order to always communicate between oil holes 57B and 57C of a closing plate 57 described later. .

  57 is a closing plate that closes the opening side 56A of the recessed portion 56 in an oil-tight state. The closing plate 57 is formed as an oblong plate as shown in FIGS. Is provided with a shallow groove 57A. The shallow groove 57A is formed by sitting on one side of the closing plate 57 in an oval shape, and an O-ring 58 described later is mounted in the shallow groove 57A. In addition, a pair of oil holes 57B and 57C are formed in the closing plate 57 at positions spaced apart from each other in the long axis direction of the oblong closing plate 57. The oil holes 57B and 57C are O-rings described later. 58 is located on the inner side in the radial direction and opens into the shallow groove 57A.

  On the other hand, annular sealing grooves 57D and 57E are formed on the other side surface of the closing plate 57 so as to surround the oil holes 57B and 57C from the outside in the radial direction. Rings 59 and 60 are attached. The closing plate 57 closes the opening side 56 </ b> A of the recessed portion 56 by being fitted into the recessed portion 56 from the outside of the valve housing 12.

  Here, of the oil holes 57B and 57C of the closing plate 57, one oil hole 57B communicates with the oil passage 34 on the opening end 29A1 side of the lid 29A as shown in FIG. 4, and through the radial hole 34A. And communicated with the pilot oil chamber 30A in the lid 29A. The other oil hole 57C communicates with the oil passage 42 of the lid body 41 as shown in FIG. 4, and also communicates with the pilot port 51E of the valve cylinder 51 and the pilot oil chamber 55 through the radial hole 42A. It is.

  58, 59 and 60 are O-rings as sealing members provided on the closing plate 57. Of the O-rings 58 to 60, the O-ring 58 is mounted in a shallow groove 57A of the closing plate 57 as shown in FIG. Then, the space between the recessed portion 56 and the closing plate 57 is sealed in an oil-tight state. The O-ring 59 is mounted in the seal groove 57D of the closing plate 57, and seals between the oil hole 57B of the closing plate 57 and the oil passage 34 of the lid 29A in an oil-tight state. The O-ring 60 is mounted in the sealing groove 57E of the closing plate 57, and seals between the oil hole 57C of the closing plate 57 and the oil passage 42 of the lid body 41 in an oil-tight state.

  61 is a communication path formed between the recessed portion 56 and the closing plate 57. The communication path 61 includes an oil groove 56B formed on the bottom side of the recessed portion 56, and oil holes 57B, 57C, and the oil passage 34 of the lid 29A and the oil passage 42 of the lid 41 are communicated with each other. That is, the communication passage 61 communicates the pilot oil chamber 30A in the lid body 29A to the oil groove 56B in the recessed portion 56 through the oil passage 34 and the oil hole 57B in the closing plate 57, and The oil hole 57C, the oil passage 42 and the radial hole 42A of the cover body 41, and the pilot port 51E of the valve cylinder 51 are always in communication with the pilot oil chamber 55.

  The control valve device 11 for the hydraulic cylinder 3 according to the present embodiment has the above-described configuration. Next, the operation thereof will be described.

  First, when the operator of the hydraulic excavator manually operates the operation lever 8A shown in FIG. 1, pilot pressure is supplied from the operation valve 8 to, for example, the pilot oil chambers 30A and 30B of the direction control valve 25 through the pilot conduits 10A and 10B. Thereby, the direction control valve 25 is switched from the neutral position (A) shown in FIG. 1 to one of the switching positions (B) and (C).

  When the directional control valve 25 is switched from the neutral position (A) to the switching position (B), the pressure oil from the hydraulic pump 1 enters the oil chamber 3B of the hydraulic cylinder 3 via the oil passage 16B and the hydraulic line 7B. The supplied pressure oil in the oil chamber 3A becomes return oil and is discharged to the hydraulic line 7A side. As a result, the rod 6 of the hydraulic cylinder 3 is driven in a direction to shrink toward the inside of the tube 4.

  At this time, the anti-drift valve 43 is a check valve body of the pilot operated check valve 44 by switching the pilot type switching valve 50 from the standby position (a) shown in FIG. 46 opens, allowing the return oil from the oil chamber 3 </ b> A to be discharged to the tank 2 via the direction control valve 25.

  Here, the anti-drift valve 43 is in a low pressure state in which the pilot pressure in the pilot pipe line 10A is close to the tank pressure while the direction control valve 25 is in the neutral position (A). The load pressure in the hydraulic cylinder 3 (oil chamber 3A) is received by the check valve body 46 of the pilot operated check valve 44 through the load pressure passage 41C, the supply / discharge port 51C, and the like. Let

  As a result, the pilot operated check valve 44 holds the check valve body 46 in a closed state by the load pressure from the hydraulic cylinder 3, and shuts off the oil passage 16A in the valve housing 12 at a midway position. This prevents the load pressure from the cylinder 3 (oil chamber 3A) from leaking to the spool sliding hole 14 side of the valve housing 12, and prohibits the rod 6 of the hydraulic cylinder 3 from moving inadvertently in the reduction direction. is there.

  Next, when the directional control valve 25 is switched from the neutral position (A) to the switching position (B) in this state, the pilot pressure supplied from the pilot line 10A to the pilot oil chamber 30A of the directional control valve 25 is changed to the pilot pressure. The pilot type switching valve 50 is also supplied to the pilot port 51E of the type switching valve 50, and the pilot type switching valve 50 is switched from the standby position (a) shown in FIG. 1 to the operating position (b).

  For this reason, the supply / discharge port 51C and the like of the pilot-type switching valve 50 are connected to the tank 2 via the tank passage 41B and the like, and the pilot operation check valve 44 has the pressure in the back pressure chamber 48 (see FIG. 3) as the tank pressure. The check valve body 46 is seated on the valve seat 45 </ b> A only by the biasing force of the spring 49.

  In this state, when the return oil is discharged from the oil chamber 3A of the hydraulic cylinder 3 toward the hydraulic line 7A, the return oil is springed before and after the valve seat 45A in the oil passage 16A in the valve housing 12. A differential pressure larger than the urging force of 49 is generated, and the check valve body 46 is opened by this differential pressure, so that the return oil in the oil passage 16A is discharged to the tank 2 side via the direction control valve 25. It is what is done.

  On the other hand, when the directional control valve 25 is switched from the neutral position (A) to the switching position (C), pressure oil higher than the load pressure of the hydraulic cylinder 3 is supplied from the hydraulic pump 1 into the oil passage 16A. Therefore, the check valve body 46 of the pilot operated check valve 44 is opened at the high pressure at this time.

  As a result, the hydraulic cylinder 3 is supplied with pressure oil into the oil chamber 3A from the hydraulic line 7A side, and return oil is discharged from the oil chamber 3B toward the tank 2 to the hydraulic line 7B and the oil path 16B. The The rod 6 of the hydraulic cylinder 3 is driven in a direction extending from the tube 4. When the directional control valve 25 is returned to the neutral position (A), the hydraulic cylinder 3 is stopped, and the anti-drift valve 43 can suppress the rod 6 from moving carelessly.

  In the above description, the case where the directional control valve 25 is switched is described. However, the directional control valve 26 also controls the hydraulic cylinder 3 and is operated in the same manner as the directional control valve 25. The control valve device 11 can speed up the movement (extension / contraction operation) of the hydraulic cylinder 3 by switching the two directional control valves 25 and 26 together.

  Thus, according to the present embodiment, the left and right lid bodies 29A and 29B constituting the directional control valve 25 are provided with a pressure resistance performance greater than that of the lid body 29A at a position close to one lid body 29A. A separate lid 41 is provided, and the lid 41 is fixed to the outer surface of the valve housing 12 in an abutting state.

  In addition to the spool 27 of the directional control valve 25, the valve housing 12 is provided with a pilot operation check valve 44 located in the middle of the oil passage 16 </ b> A. A pilot-type switching valve 50 for switching control of supply and stop of load pressure (back pressure) is provided.

  Thus, when the cover body 41 including the pilot type switching valve 50 is formed using, for example, a heavy cast iron material, the load pressure from the hydraulic cylinder 3 is guided to the load pressure passage 41C and the like. Sufficient durability and pressure resistance against load pressure can be imparted to the lid 41.

  Further, the lid bodies 29A and 29B of the direction control valve 25 can be formed using, for example, an aluminum-based lightweight material, and the pilot pressure from the operation valve 8 is pilot oil chambers 30A and 30B inside these. The lid bodies 29A and 29B can be given sufficient pressure resistance against the pilot pressure.

  Further, by forming the lid body 29A and the lid body 41 that are arranged close to each other from different materials, one lid body 29A can be formed with a reduced weight, and sufficient withstand pressure performance against pilot pressure. Therefore, it is possible to improve the handleability during assembly and maintenance of the apparatus and improve workability.

  Further, the lid body 41 is formed using, for example, a heavy cast iron-based material, so that sufficient durability and pressure resistance can be given to the load pressure from the hydraulic cylinder 3. Can be made small to the minimum required size, and this also improves the handleability during assembly and maintenance of the apparatus, and improves workability.

  Further, according to the present embodiment, the lid 41 has an abutting surface with the valve housing 12 for guiding the pilot pressure from the pilot oil chamber 30A in one lid 29A through the oil passage 34 and the like. An oil passage 42 extending in parallel to the fitting hole 41A of the valve cylinder 51 is provided, and the valve housing 12 has a recessed portion 56 formed of a bottomed hole that opens to the abutting surface side with the lid bodies 29A and 41. The opening 56A of the recess 56 is closed in an oil-tight state, two oil holes 57B and 57C are formed, and the communication passage communicates with the pilot oil chamber 30A (oil passage 34) and the oil passage 42. 61 is provided with a closing plate 57 formed between the recessed portion 56.

  For this reason, one of the oil holes 57B and 57C formed in the closing plate 57 is communicated with the pilot oil chamber 30A via the oil passage 34, and the other oil hole 57C is communicated with the oil passage 42. Thus, for example, as described in the prior art, without using a pilot pipe or the like which is an external pipe, the communication path 61 between the recessed portion 56 and the closing plate 57 is provided between the two lid bodies 29A and 41. The pilot oil chamber 30A (oil passage 34) and the oil passage 42 can be easily connected.

  In this way, the space between the pilot oil chamber 30A (oil passage 34) in the lid 29A and the oil passage 42 on the lid 41 side is formed between the recessed portion 56 of the valve housing 12 and the closing plate 57. By using the communication path 61 for communication, it is possible to suppress the occurrence of oil leakage and the like as compared with external piping and the like, and it is possible to improve workability during assembly and maintenance of the apparatus.

  The valve housing 12 is provided with a pilot operated check valve 44, and the lid body 41 is provided with a pilot type switching valve for switching control of supply and stop of load pressure (back pressure) to the pilot operated check valve 44. Therefore, the pilot in the valve cylinder 51 is provided through the oil hole 57B of the closing plate 57, the oil groove 56B of the recessed portion 56, the oil hole 57C, and the oil passage 42 from the inside of one lid 29A (pilot oil chamber 30A). The spool valve body 52 of the pilot type switching valve 50 can be smoothly switched and controlled by the pilot pressure introduced into the oil chamber 55.

  Thereby, the action | operation of the anti-drift valve 43 which consists of the pilot operation check valve 44 and the pilot type switching valve 50 can be stabilized. When the spool 27 is held in the neutral position in the spool sliding hole 14 of the valve housing 12, there is a problem that the hydraulic cylinder 3 is inadvertently moved due to a leak of the load pressure. The operation of the hydraulic cylinder 3 can be stabilized.

  Therefore, in the present embodiment, it is not necessary to use a pilot pipe or the like that is an external pipe as in the prior art, the number of parts can be reduced, and the pilot is directed from one lid 29A into a separate lid 41. The pressure can be easily circulated, and for example, occurrence of oil leakage at the connection location can be suppressed satisfactorily.

  Moreover, by forming the lid body 29A and the lid body 41 by using different materials and different members, it is possible to give appropriate pressure resistance performance to the lid bodies 29A and 41, and during assembly and maintenance of the apparatus. In addition to improving the handleability and improving workability, it is also possible to reduce costs.

  Next, FIG. 9 and FIG. 10 show a second embodiment of the present invention. In this embodiment, the same reference numerals are given to the same components as those in the first embodiment described above, and the description thereof will be given. Shall be omitted. However, the feature of the present embodiment is that the closing plate 71 is constituted by a circular plate.

  Here, the closing plate 71 is configured in substantially the same manner as the closing plate 57 described in the first embodiment, and an oblong shallow groove 71A is provided on one side surface thereof. An O-ring 72 as a seal member is mounted in the shallow groove 71A. Further, the closing plate 71 is provided with a pair of oil holes 71B and 71C at positions separated from each other. On the other hand, annular sealing grooves 71D and 71E are formed on the other side of the closing plate 71 so as to surround the oil holes 71B and 71C from the outside in the radial direction, and the sealing grooves 71D and 71E serve as sealing members. O-rings 73 and 74 are attached.

  However, in this case, since the closing plate 71 is formed as a circular flat plate, the recessed portion 56 (see FIG. 4) of the valve housing 12 is also circular so that the closing plate 71 is fitted and attached. It is formed as a recess.

  Thus, in the present embodiment configured as described above, it is possible to obtain substantially the same operational effects as those of the first embodiment. However, in this embodiment, since the closing plate 71 is formed as a circular flat plate, the closing plate 71 can be easily manufactured and processed.

  Next, FIGS. 11 and 12 show a third embodiment of the present invention. In this embodiment, the same reference numerals are given to the same components as those of the first embodiment described above, and the description thereof will be given. Shall be omitted. However, the present embodiment is characterized in that a packing member 82, 83, 84 is attached to the closing plate 81 as a sealing member.

  Here, the closing plate 81 is formed as a flat plate having an oval shape in substantially the same manner as the closing plate 57 described in the first embodiment. However, an oblong ring groove 81A is formed on one side surface of the closing plate 81, and an annular packing member 82 is attached to the ring groove 81A. Further, the closing plate 81 is provided with a pair of oil holes 81B and 81C which are located on the radially inner side of the ring groove 81A having an oval shape and are separated from each other in the long axis direction. Further, annular ring grooves 81D and 81E are formed on the other side surface of the closing plate 81 so as to surround the oil holes 81B and 81C from the outside in the radial direction, and an annular packing member is formed in these ring grooves 81D and 81E. 83 and 84 are stuck.

  The closing plate 81 is fitted and attached to the recessed portion 56 (see FIGS. 5 and 6) of the valve housing 12 in the same manner as the closing plate 57 described in the first embodiment. The space between the recessed portion 56 and the closing plate 81 is sealed in an oil-tight state. The packing members 83 and 84 function in the same manner as the O-rings 59 and 60 described in the first embodiment, and the oil holes 81B and 81C of the closing plate 81 and the oil passage 34 and the lid 41 of the lid 29A. The oil passage 42 is sealed in an oil-tight state.

  Thus, in the present embodiment configured as described above, it is possible to obtain substantially the same operational effects as those of the first embodiment. However, in the present embodiment, since the packing members 82, 83, and 84 are provided by being attached to the closing plate 81, a seal member such as an O-ring can be omitted.

  Next, FIGS. 13 and 14 show a fourth embodiment of the present invention. In this embodiment, the same reference numerals are given to the same components as those of the first embodiment described above, and the description thereof will be given. Shall be omitted. However, the present embodiment is characterized in that a sealing film 92 is attached to the closing plate 91 as a sealing member.

  Here, the closing plate 91 is formed in an oval shape in substantially the same manner as the closing plate 57 described in the first embodiment. However, an edge 91A is formed integrally on the outer peripheral side of the closing plate 91, and this edge 91A is constant in the thickness direction of the closing plate 91 (the axial direction of oil holes 91B and 91C described later). Protrudes at a height of.

  Then, a sealing film 92 made of an elastic material such as rubber is attached to the surface side of the closing plate 91 and the edge portion 91A. The structure covers the entire circumference. The obstruction plate 91 is formed with a pair of oil holes 91B and 91C at positions spaced apart from each other in the major axis direction of the oblong obstruction plate 91. The oil holes 91B and 91C are formed in the obstruction plate 91. The seal film 92 is penetrated on the surface side.

  The closing plate 91 is fitted and attached to the recessed portion 56 (see FIGS. 5 and 6) of the valve housing 12 in the same manner as the closing plate 57 described in the first embodiment. The opening side 56A and the like are sealed in an oil-tight state through a seal film 92.

  Thus, in the present embodiment configured as described above, it is possible to obtain substantially the same operational effects as those of the first embodiment. However, in the present embodiment, since the sealing film 92 is provided on the surface side of the closing plate 91 and the edge portion 91A, the sealing member such as an O-ring can be omitted.

  In the fourth embodiment, the closing plate 91 is formed as a shallow container having an oval shape by the edge portion 91A as shown in FIG. For this reason, it is not necessary to provide an oil groove 56B as shown in FIG. 5, for example, on the bottom side of the recessed portion 56 into which the closing plate 91 is fitted.

  Further, in each of the above embodiments, the oil passage 34 is provided in the lid body 29A of the direction control valve 25, and the pilot oil chamber 30A is blocked by the oil passage 34 through the oil hole 57B (71B) of the closing plate 57 (71, 81, 91). , 81B, 91B), as an example. However, the present invention is not limited to this, for example, a configuration in which the pilot oil chamber 30A of the lid 29A is directly communicated with the oil hole 57B (71B, 81B, 91B) of the closing plate 57 (71, 81, 91). It is good.

  In each of the above embodiments, the control valve device 11 for the hydraulic cylinder 3 has been described as an example of the control valve device. However, the present invention is not limited to this, and may be applied to a control valve device such as a hydraulic motor.

1 is a hydraulic circuit diagram for driving a hydraulic cylinder to which a control valve device according to a first embodiment of the present invention is applied. It is a longitudinal cross-sectional view which shows the control valve apparatus in FIG. It is sectional drawing which expands and shows the anti-drift valve in FIG. 2 with a part of direction control valve. It is a principal part expanded sectional view which shows the anti-drift valve in FIG. 3 with a recessed part, a closure board, etc. FIG. It is sectional drawing which expands and shows the hollow part of a valve housing in the state which removed the obstruction board etc. in FIG. It is sectional drawing which looked at the hollow part from the arrow VI-VI direction in FIG. It is a front view which shows a blockage board alone. It is sectional drawing which looked at the obstruction board from the arrow VIII-VIII direction in FIG. It is a front view which shows the obstruction board employ | adopted by 2nd Embodiment alone. It is sectional drawing which looked at the obstruction board from the arrow XX direction in FIG. It is a front view which shows the obstruction board employ | adopted in 3rd Embodiment alone. It is sectional drawing which looked at the obstruction board from the arrow XII-XII direction in FIG. It is a front view which shows the obstruction board employ | adopted by 4th Embodiment alone. It is sectional drawing which looked at the obstruction board from the arrow XIV-XIV direction in FIG.

Explanation of symbols

1 Hydraulic pump 2 Tank 3 Hydraulic cylinder (hydraulic actuator)
7A, 7B Hydraulic pipeline 8 Pilot operation valve 10A, 10B Pilot pipeline 11 Control valve device 12, 13 Valve housing 14, 15 Spool sliding hole 16A, 16B Oil passage 17, 18 Oil passage 19A, 19B, 20A, 20B Oil Groove (tank side oil passage)
21, 23 High pressure passage 22, 24 Check valve 25, 26 Direction control valve 27, 28 Spool 29A, 29B Lid 29A1 Open end 30A, 30B Pilot oil chamber 32, 38 Return spring 34 Oil path 41 Separate lid 42 Oil path 43 Anti-drift valve 44 Pilot operated check valve 46 Check valve body 48 Back pressure chamber 50 Pilot type switching valve 51 Valve cylinder 51C Supply / exhaust port 51D Load pressure port 51E Pilot port 51F Low pressure passage 52 Spool valve body 56 Recessed part 56A Opening side 56B Oil groove 57, 71, 81, 91 Closure plate 57B, 57C, 71B, 71C, 81B, 81C, 91B, 91C Oil hole 61 Communication path

Claims (3)

A valve housing provided with a spool sliding hole and a plurality of oil passages communicating with the spool sliding hole, and a spool which is inserted into the spool sliding hole of the valve housing and communicates and blocks between the plurality of oil passages And a left and right lid body that is provided on the valve housing and is located on both sides in the axial direction of the spool and forms a pilot oil chamber for driving the spool in the axial direction. In
In the valve housing, a separate lid is provided in an abutting state at a position close to one of the left and right lids,
The one lid body is provided with one oil passage extending from the pilot oil chamber in the one lid body toward the abutting surface side of the lid body and the valve housing,
Wherein the separate lid, for guiding the pilot pressure to the separate lid body through the oil passage of the one from the pilot oil chamber of the lid body of the one, and the valve housing to said another number of cover body setting the other extending toward the the abutment surface side of the oil passage,
The valve housing has been formed as an opening to a bottom hole in the abutment surface of the said one of the oil passage and the other above the oil passage so as to communicate with each other one of the cover and a separate lid Providing a recessed portion and a closing plate for closing the opening side of the recessed portion in an oil-tight state ;
The closing plate is provided with an oil hole communicating with the one oil passage and the other oil passage,
A communication path including the oil hole for communicating the one oil path and the other oil path is formed between the recessed portion and the closing plate,
Wherein the recessed portion and the closure plate which closes the open side of the control valve device, characterized in that said one of the lid and a separate lid is configured you contact.   2. The control valve device according to claim 1, wherein the separate lid is formed of a material having a pressure resistance higher than that of the one lid. The valve housing is located in the middle of an actuator side oil passage connected to a hydraulic actuator among the plurality of oil passages, and receives a load pressure from the hydraulic actuator when the spool is in a neutral position. the pilot operated check valve for blocking between the spool and the hydraulic actuator is provided, wherein the separate lid body, said one oil passage from the pilot oil chamber, the pilot guided via the communication path and the other oil passage 3. The control valve device according to claim 1, wherein a pilot-type switching valve that cuts off the load pressure supplied to the pilot operation check valve by pressure is provided. 4.

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