JP2017053381A - Control valve unit of work machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a control valve unit of a work machine, which can wholly warm up a hydraulic circuit without specially providing a circuit for warming-up.SOLUTION: A control valve unit of a work machine comprises a valve body 30a, supply ports PA, PB, a discharge port T, a control valve, a bypass flow passage 26A for letting hydraulic oil supplied from the supply ports PA, PB bypass the control valve and flow to the discharge port T during non-operation of a hydraulic actuator, and bypass valves 27A, 27B interposed in the bypass flow passage 26A and opened during non-operation of the hydraulic actuator. The bypass valves 27A, 27B are arranged close to one end 31a of the valve body 30a, and at least one port of the supply ports PA, PB and the discharge port T is arranged in a section on the opposite side from the one end.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a control valve unit for a work machine having a warm-up function.

  Conventionally, various warm-up control devices for warming a hydraulic circuit at the time of cold start of a working machine such as a hydraulic excavator have been proposed. In general warm-up control of a hydraulic circuit, control is performed so that each part in the hydraulic circuit is warmed by warming the hydraulic oil flowing through the hydraulic circuit, and the entire hydraulic circuit is appropriately heated.

  For example, in a work machine having a center bypass that is an oil passage for returning hydraulic oil to a hydraulic oil tank when the work machine is not operated (neutral), warm-up operation is performed by repeatedly performing relief and neutral. The machine is done. That is, (1) by performing an input operation in a direction in which the cylinder is further extended from a position where the cylinder is provided to the work machine, or from a position where the cylinder is not further reduced, or a stick cylinder. By making an input operation in a direction to reduce the pressure, the hydraulic oil is actively circulated through the relief flow path (relief flow path), and (2) the hydraulic oil is circulated to the center bypass when not operated. This is repeated, and the entire hydraulic circuit is warmed up by circulating the working oil through the two flow paths of the relief flow path and the center bypass.

  By the way, in recent work machines, since it is easy to adjust the performance of the hydraulic circuit, many of them have a hydraulic circuit having four metering valves that can be individually controlled with respect to one actuator. Since such a hydraulic circuit does not have a center bypass, a bypass valve is required to control the system pressure.

  In addition, for example, in the temperature raising circuit of the solenoid valve unit disclosed in Patent Document 1, a solenoid valve unit having a plurality of solenoid valves each having a valve pressure port and a valve tank port while forming a hydraulic pressure inlet and a tank outlet In each temperature riser circuit, each valve pressure port of the solenoid valve is connected to one common pressure oil passage, and each valve tank port of the solenoid valve is connected to one common tank oil passage to operate from the hydraulic inlet The oil branches into two, one of which flows to the common pressure oil passage and the other to the common tank oil passage. This makes it possible to improve the warm-up function even with the addition of a small number of parts.

  Patent Document 2 discloses a warm-up unit that is directly attached to the left and right pilot pressure receiving chambers of the main control valve of the pilot hydraulic circuit. Inside the warm-up unit, three oil passages communicate with each other through connection ports that are directly connected to the pilot oil passage, the warm-up oil passage, and the pilot pressure receiving chambers. ing. Pressure oil from the pilot hydraulic power source is directly introduced from the warm-up oil passage to each pilot pressure receiving chamber through the junction of each oil passage. The pressure oil returns to the oil tank through the pilot oil passage. The pressure oil in the oil tank that has been heated in advance by the engine warm-up operation is circulated, and the pressure oil in each pilot pressure receiving chamber is heated in advance.

  According to the warm-up unit described in Patent Document 2, since the pilot oil passage, the warm-up oil passage, and the pilot pressure receiving chamber can be directly connected via the warm-up unit, each pilot pressure receiving chamber of the main control valve can be connected. It is not necessary to connect a large number of pipes individually to each of the pilot pressure chambers, and it is only necessary to connect a warm-up unit, which is a single connection port, to each pilot pressure receiving chamber. Is easy to process. In other words, the compact warm-up unit enables easy connection of necessary piping with a simple structure without increasing the number of parts.

JP 2000-220768 A JP 2003-004009 A

However, in the hydraulic circuit having the metering valve described above, the bypass valve and the relief valve are located at a biased position of the valve body of the control valve unit. The entire circuit cannot be warmed.
Further, in the warm-up unit disclosed in Patent Document 1 and Patent Document 2, although it is possible to warm up the hydraulic circuit as a whole, a special warm-up circuit is required in the hydraulic circuit. This complicates the hydraulic circuit and increases the manufacturing cost.

  The present invention has been devised in view of the above problems, and provides a control valve unit for a work machine that can warm up a hydraulic circuit as a whole without specially providing a circuit for warming up. The purpose is to provide.

  (1) In order to achieve the above object, a control valve unit of a work machine according to the present invention is formed in a valve body, a supply port formed in the valve body and supplied with hydraulic oil, and formed in the valve body. A discharge port through which the hydraulic oil is discharged, a control valve mounted on the valve body and controlling supply of the hydraulic oil to the hydraulic actuator, and formed in the valve body, when the hydraulic actuator is not operated. The hydraulic oil supplied from the supply port is interposed in the bypass flow path for bypassing the control valve and flowing to the discharge port, and is opened when the hydraulic actuator is not operated. A control valve unit for a work machine, wherein the bypass valve is the valve valve. Together are arranged close to one end of the I, at least one port of said supply port and said discharge port is characterized in that it is arranged on the opposite side sections and the end.

  (2) It is preferable that the at least one port is arranged close to the other end in the longitudinal direction.

  (3) It is preferable that both the supply port and the discharge port are arranged close to the other end in the longitudinal direction.

  (4) It is preferable that the valve body includes a body main body and a cover body removably attached to one end of the body main body in the longitudinal direction, and the bypass valve is incorporated in the cover body.

  (5) It is preferable that an additional valve can be installed between the body main body and the cover body.

According to the present invention, the bypass valve is arranged close to one end of the valve body, and at least one of the supply port and the discharge port is arranged in a section opposite to the one end. With this arrangement, when the hydraulic actuator is not operated, the hydraulic oil can be distributed to a region that occupies most of the valve body.
Therefore, it is possible to warm up the hydraulic circuit as a whole without changing the arrangement of the supply port, the discharge port, and the bypass valve, which are conventionally provided, without providing a special warm-up circuit.

It is a typical perspective view showing the whole work machine composition concerning one embodiment of the present invention. It is a mimetic diagram showing the whole hydraulic circuit composition concerning one embodiment of the present invention. It is a typical top view which shows the structure of the control valve unit as one Embodiment of this invention. It is a typical top view which shows the structure of the conventional control valve unit.

Embodiments of the present invention will be described below with reference to the drawings.
Note that each embodiment described below is merely an example, and there is no intention of excluding various modifications and technical applications that are not explicitly described in the following embodiment. Each configuration of the following embodiments can be implemented with various modifications without departing from the spirit thereof, and can be selected as necessary or can be appropriately combined.
In the following embodiment, an example in which the control valve unit of the work machine of the present invention is applied to a hydraulic excavator as a work machine is shown. can do.

[1. Excavator configuration]
A configuration of a hydraulic excavator 1 according to an embodiment of the present invention will be described with reference to FIG. The hydraulic excavator 1 includes a lower traveling body 2 equipped with a crawler type traveling device, and an upper revolving body 3 that is rotatably mounted on the lower traveling body 2. A cab 4 on which an operator (operator) rides and a front work device 5 provided so as to extend forward of the vehicle adjacent to the cab 4 are provided on the vehicle front side of the upper swing body 3. A counterweight 6 for maintaining the weight balance of the airframe is disposed at the rearmost end of the upper swing body 3, and an engine room 7 is formed immediately before the counterweight.

The front work device 5 includes a boom 5BM, a stick 5STK, and a bucket 5BKT. The boom 5BM is pivotally supported with respect to the upper swing body 3 so that the base end portion thereof can be raised and lowered. Further, a boom cylinder 15BM is interposed between the boom 5BM and the upper swing body 3, and the boom 5BM swings according to the expansion and contraction operation of the boom cylinder 15BM.
Similarly, the stick 5STK is pivotally supported at its base end so as to be swingable with respect to the tip of the boom 5BM, and the bucket 5BKT is pivotally supported at the tip of the stick 5STK. A stick cylinder 15STK is interposed between the boom 5BM and the stick 5STK, and a bucket cylinder 15BKT is interposed between the stick 5STK and the bucket 5BKT. The stick 5STK and the bucket 5BKT swing according to the expansion / contraction operation of the stick cylinder 15STK and the bucket cylinder 15BKT, respectively.

In the engine room 7, an engine 11 that generates hydraulic pressure, which is a drive source of the excavator 1, is disposed. Two hydraulic pumps (not shown) are arranged in a pump room (not shown) adjacent to the engine room 7. The hydraulic pump is driven by the engine 11 to discharge the hydraulic oil, and supplies the hydraulic oil to various hydraulic actuators such as a hydraulic cylinder and a hydraulic motor mounted on the hydraulic excavator 1. Examples of the hydraulic actuator that receives the supply of hydraulic oil from the hydraulic pump include a boom cylinder 15BM, a stick cylinder 15STK, a bucket cylinder 15BKT, a turning motor (not shown), and a travel motor.
Inside the cab 4, there are provided various input levers and pedals for inputting the operation amounts of these various hydraulic devices.

[2. Configuration of hydraulic circuit]
A configuration of a hydraulic circuit according to an embodiment of the present invention will be described with reference to FIG. 2 shows the hydraulic circuit of the boom cylinder 15BM (see FIG. 1), the stick cylinder 15STK (see FIG. 1), and the travel motors 15TRR and 15TRL (omitted in FIG. 1), and the other hydraulic circuits are omitted. Yes. Also in the following description, only the boom cylinder 15BM (see FIG. 1), the stick cylinder 15STK (see FIG. 1) and the hydraulic circuit of the travel motor will be described for convenience.

In such a hydraulic circuit 10, the boom control valve 14BM, the right traveling motor control valve 14TRR, the left traveling motor control valve 14TRL, and the stick control valve 14STK are operated by the lever 16BM, the pedal 17TRR, the pedal 17TRL, and the lever 16STK, respectively. The
The boom control valve 14BM controls expansion and contraction of the boom cylinder 15BM according to the operation of the lever 16BM. The right traveling motor control valve 14TRR controls the operation of the right traveling motor 15TRR in response to depression of the pedal 17TRR. The left travel motor control valve 14TRL controls the operation of the left travel motor 15TRL in response to the depression of the pedal 17TRL. The stick control valve 14STK controls the operation of the stick cylinder 15STK according to the operation of the lever 16STK.

Hereinafter, when the boom cylinder 15BM, the right traveling motor 15TRR, the left traveling motor 15TRL, and the stick cylinder 15STK are not particularly distinguished, they are referred to as a hydraulic actuator 15, and the control valves 14BM, 14TRR, 14TRL, and 14STK are not particularly distinguished. Is represented as a control valve 14, levers 16BM and 16STK are denoted as lever 16 when not particularly distinguished, and pedals 17TRR and 17TRL are denoted as pedal 17 when not particularly distinguished.
Although shown in a simplified manner in FIG. 2, in the present embodiment, each control valve 14 is constituted by four metering valves that can be individually controlled. Each control valve 14 is not limited to the one constituted by four metering valves, and various types of valves can be used.

  The hydraulic circuit 10 is roughly divided into two circuits corresponding to two main pumps (hereinafter also simply referred to as pumps) 12 driven by the engine 11, and a pair of travel motors 15TRR is provided between these two circuits. , 15TRL for operating at a constant speed is provided, and a merging valve 19 for controlling the exchange of hydraulic oil between one circuit and the other circuit (between the two pumps 12). Is provided.

Each pump discharge passage 21 of each pump 12 is provided with a warm-up throttle valve 22. The throttle valve 22 is a warm-up valve. When it is determined by the controller (not shown) that warm-up is necessary, the throttle valve 22 is controlled to the fully open position to communicate the pump discharge passage 21 of each pump 12 with the tank 13. . That is, automatic warm-up is performed by circulating hydraulic oil.
The case where it is determined that warm-up is necessary is a case where each pump 12 is idling, or a case where the temperature of hydraulic oil or the temperature of engine coolant detected by a sensor (not shown) is low.

  A pair of check valves 24 are interposed in the return flow path 23 between the pump discharge flow path 21 and the tank 13 of each pump 12, and a pressure setting relief is provided between the check valves 24 and 24. A valve 25 is provided. When the hydraulic pressure exceeds the set pressure of the relief valve 25, the relief valve 25 is opened and the hydraulic oil is returned to the tank 13.

A pair of bypass valves 27A and 27B are provided in the other return flow path 26 between the pump discharge flow path 21 and the tank 13 of each pump 12. In other words, a return flow path 26 common to the bypass valves 27A and 27B (common to two circuits corresponding to the two pumps 12) is formed between the bypass valves 27A and 27B.
Hereinafter, when the bypass valves 27A and 27B are not distinguished, they are referred to as bypass valves 27.

When an operation amount (depression amount) is input from the lever 16 or the pedal 17, the controller (not shown) closes the bypass valve 27 and controls the corresponding control according to the operation amount (depression amount). The opening degree of the valve 14 and, in turn, the amount of hydraulic oil supplied by the pump 12 to the hydraulic actuator 15 is controlled.
On the other hand, when the operation amount (depression amount) is not detected for each lever 16 and each pedal 17, the controller opens the bypass valve 27 and drains the hydraulic oil pumped by the pump 12 to the tank 13. Thus, the supply of hydraulic oil to each hydraulic actuator 14 is stopped.

[3. Configuration of control valve unit]
A configuration of a control valve unit (hereinafter also simply referred to as a valve unit) 30 as an embodiment of the present invention will be described with reference to FIGS.
The valve unit 30 is configured as a unit by mounting or forming a valve or a flow channel in a range indicated by a one-dot chain line in FIG. 2 on the valve body 30a. That is, the valve unit 30 includes a valve body 30a, a control valve 14, a straight traveling valve 18, a merging valve 19, a throttle valve 22, a check valve 24, a relief valve 25, and bypass valves 27A and 27B provided on the valve body 30a. And is configured.
Focusing on the pump discharge path 21 and the return flow path 26 passing through the bypass valves 27A and 27B, the valve unit 30 includes flow paths 21A and 21B constituting part of the pump discharge paths 21 and 21 in the valve body 30a. A flow path (bypass flow path) 26A constituting a part of the return flow path 26 is formed. Bypass valves 27A and 27B are provided in the flow path 26A. The valve unit 30 (valve body 30a) uses the pump ports (supply ports) PA and PB forming one end of the flow paths 21A and 21B as the hydraulic oil inlet. The tank port (discharge port) T that forms one end of the flow path 26A is connected to the external flow path that is connected to the tank 13 as a hydraulic oil outlet.

  When neither the lever 16 nor the pedal 17 is operated (not depressed), the hydraulic oil pumped from the pump 12 flows into the valve unit 30 from the pump ports PA and PB and flows into the flow path. 21A, 21B, bypass valves 27A, 27B and flow path 26A are passed in this order, discharged from the valve body 30a through the tank port T, and returned to the tank 13.

As shown in FIG. 3 which is a schematic plan view when installed on the work machine, the valve body 30a is formed in a rectangular shape in plan view, and the bypass valves 27A and 27B are arranged in the longitudinal direction of the valve body 30a (see FIG. 3). 3 is arranged in the section on the right side in FIG. 3 with respect to the center line CL that bisects the center line CL, and the valve ports PA and PB and the tank port T are arranged in the section on the left side in FIG. ing. In addition, the bypass valves 27 </ b> A and 27 </ b> B are installed close to (on the right end of) the short side (one end in the longitudinal direction) 31 a on the right side in FIG. 3 of the upper surface 31.
That is, the bypass valves 27A and 27B are arranged close to one end (the short side on the right side) 31a in the longitudinal direction of the valve body 30a, and the valve ports PA and PB and the tank port T are located with respect to the center line CL. The bypass valve 27A, 27B is disposed in a section (section on the left side of the center line CL) opposite to the section (section on the right side of the center line CL) where the bypass valves 27A and 27B are disposed.

  In the present embodiment, the valve ports PA and PB and the tank port T are respectively placed close to the left short side (the other end in the longitudinal direction) 31c in FIG. 3 (disposed at the left end). Specifically, the valve ports PA and PB open on the side surface with the short side 31c as the upper edge, and the tank port T opens near the short side 31c on the side surface with the long side 31b as the upper edge.

  Furthermore, in the present embodiment, the flow paths 21A, 21B, and 26A are arranged over substantially the entire valve body 30a in the short direction (vertical direction in FIG. 3).

  Here, arranging near the short side 31a means arranging within the predetermined distance L0 from the short side 31a. Similarly, arranging near the short side 31c means within within the predetermined distance L0 from the short side 31c. It means arranging.

  Alternatively, when the bypass valves 27A and 27B are arranged close to the short side 31a of the valve body 30a, “a valve other than the bypass valves 27A and 27B and disposed closest to the short side 31a” and “short It can also be defined that the bypass valves 27A and 27B are arranged in a region between the side 31a ". In other words, among the valves attached to the valve body 30a, if the bypass valves 27A and 27B are disposed closest to the “short side 31a” side (may be disposed on the side surface with the short side 31a as the upper edge). In other words, the bypass valves 27A and 27B can be defined as being arranged close to the short side 31a of the valve body 30a.

  Similarly, when the ports PA, PB, T are arranged close to the short side 31c of the valve body 30a, the port PA, PB, T is arranged in a region between the “valve arranged closest to the short side 31c” and the “short side 31c”. , Ports PA, PB, and T can be defined. In other words, if the ports PA, PB, T are arranged on the “short side 31c” side of any valve attached to the valve body 30a (they may be arranged on the side surface with the short side 31c as the upper edge). In other words, the ports PA, PB, and T can be defined as being arranged close to the short side 31c.

  As a result of such an arrangement, the flow paths 21A and 21B are formed over substantially the entire length in the longitudinal direction across the center line CL, and the flow path 26A also extends over the almost entire length in the longitudinal direction across the center line CL. Will be formed. Therefore, when the hydraulic actuator is not operated, the hydraulic oil passes through the flow passages 21A and 21B through the substantially entire length of the valve body 30a until it passes through the bypass valves 27A and 27B, and the bypass valves 27A and 27B. After passing, the U-turn is made, and the valve body 30a again passes through the substantially entire length in the longitudinal direction through the flow path 26A.

  The bypass valves 27A and 27B are built in a cover portion (cover body) 30b outside the section R where the throttle valve 22 (see FIG. 2) is disposed. The cover 30b is removable, and when adding a valve (hereinafter referred to as an additional valve) due to the addition of an attachment or a design change, the cover 30b and the body body 30c of the valve body 30a (the valve body 30a). The additional valve is installed between the first portion and the cover portion 30b.

Here, in order to compare with the valve unit 30 as one embodiment of the present invention, a conventional valve unit 130 will be described with reference to FIG.
Like the valve unit 30, the valve unit 130 is configured as a unit by providing the valve body 130a with a range indicated by a one-dot chain line in FIG. As shown in FIG. 4, the valve body 130a is formed in a rectangular shape in plan view. In the valve body 130a, the pump ports PA and PB, the tank port T, and the bypass valves 27A and 27B are all left of the center line CL. It differs from the valve unit 30 in that it is concentrated and arranged near the short side of the section.
Thus, since the flow paths 21A, 21B, and 26B are concentrated on a part of the valve unit 130, the hydraulic oil flows only to the part when the hydraulic actuator is not operated.

[4. Action / Effect]
As in the conventional valve unit 130 shown in FIG. 4, if the hydraulic oil flows only to the biased section of the valve body 130 a when the hydraulic actuator 14 is not operated, only a part of the valve body becomes hot, The thermal shock due to the difference in expansion rate causes distortion and sticks the control valve, and the valve body as a whole may be insufficiently warmed up.

On the other hand, according to the control valve unit 30 of the working machine of one embodiment of the present invention, as shown in FIG. 3, in the valve body 30a, the bypass valves 27A and 27B are arranged close to the short side 31a. Since the ports PA and PB and the tank port T are disposed in the section opposite to the section where the bypass valves 27A and 27B are disposed, the flow paths 21A, 21B and 26A are formed along the longitudinal direction. Can do.
Therefore, when the hydraulic actuator 14 is not operated, the entire valve body 30a can be heated uniformly, preventing the occurrence of a thermal shock and effectively warming up.

  Further, the valve body 30a can be warmed up as a whole only by changing the arrangement of the valve ports PA and PB, the tank port T and the bypass valves 27A and 27B which have been conventionally provided. The valve body 30a can be warmed up as a whole without providing the special configuration.

  Furthermore, since the valve ports PA and PB and the tank port T are arranged close to the short side 31c, the flow paths 21A, 21B and 26A can be formed over substantially the entire length in the longitudinal direction. Therefore, the entire valve body 30a can be reliably heated when the hydraulic actuator 14 is not operated.

  Further, since both the pump ports PA and PB serving as the hydraulic oil inlet and the tank port T serving as the hydraulic oil outlet are disposed close to the short side 31c opposite to the bypass valves 27A and 27B, the pump port PA , PB flows through the bypass valves 27A and 27B and flows toward the tank port T after passing through the bypass valves 27A and 27B. Therefore, the hydraulic oil flows in a reciprocating manner over the substantially entire length of the valve body 30a, and the valve body 30a can be warmed up more effectively. Furthermore, by arranging the flow paths 21A, 21B, and 26A along the short direction (vertical direction in FIG. 3) of the valve body 30a, the valve body is equally distributed not only in the longitudinal direction but also in the short direction. It becomes possible to warm up 30a.

Furthermore, even when an additional valve is installed in the control unit 30, since the bypass valves 27A and 27B are attached to the cover portion 30b, the bypass valves 27A and 27B can be brought close to the end of the valve body 30a. That is, since the additional valve is installed between the cover part 30b and the body main body 30c, even when the additional valve is installed, the cover part 30b and the bypass valves 27A and 27B can be arranged at the end of the valve body 30a. it can.
Therefore, even when an additional valve is installed, the flow paths 21A, 21B, and 26A formed between the bypass valves 27A and 27B and the ports PA, PB, and T extend over substantially the entire length in the longitudinal direction of the valve body 30a. Can be formed.

[5. Others]
(1) The bypass valves 27A and 27B are arranged close to one end of the valve body 30a, and at least one of the pump ports PA and PB and the tank port T is arranged in a section opposite to the one end. If so, the arrangement of the pump ports PA and PB, the tank port T, and the bypass valves 27A and 27B is not limited to the arrangement of the above embodiment shown in FIG.

For example, in FIG. 3, the tank port T may be opened on the side surface with the short side 31c of the upper surface 31 as the upper edge, like the valve ports PA and PB. Conversely, the valve ports PA and PB, like the tank port T, may be opened closer to the short side 31c on the side surface with the long side 31b of the upper surface 31 as the upper edge.
Alternatively, in FIG. 3, at least one of the valve ports PA and PB and the tank port T is left, and the remaining ports are arranged in a section on the right side of the center line CL, like the bypass valves 27A and 27B. May be.

  (2) The bypass valves 27A and 27B are opened together with the throttle valve 22 not only when the hydraulic actuator 14 is not operated but also during automatic warm-up, and warm-up is performed by the flow paths 21A, 21B, and 26A. You may do it.

5 Front Working Device 10 Hydraulic Circuit 12 Pump 13 Tank 14BM Boom Control Valve 14BKT Bucket Control Valve 14STK Stick Control Valve 14TRL Left Travel Motor Control Valve 14TRR Right Travel Motor Control Valve 15 Hydraulic Actuator 21 Pump Discharge Channel 21A, 21B Pump Discharge Of the channel 21, a channel formed in the valve unit 30 26 Return channel 26A Of the return channel 26, a channel formed in the valve unit 30 (bypass channel)
27, 27A, 27B Bypass valve 30 Control valve unit 30a Valve body 30b Cover portion (cover body) of valve body 30a
30c Body body of valve body 30a 31 Upper surface of valve body 30a 31c Short side of upper surface 31 (the other end in the longitudinal direction)
31a Short side of upper surface 31 (one end in the longitudinal direction)
31b Long side of upper surface 31 L Total length of valve body 30a L0 Predetermined distance PA, PB Pump port (supply port)
R Section where throttle valve 22 is placed T Tank port (discharge port)

Claims (5)

A valve body;
A supply port formed in the valve body and supplied with hydraulic oil;
A discharge port formed in the valve body and from which the hydraulic oil is discharged;
A control valve mounted on the valve body and controlling supply of the hydraulic oil to a hydraulic actuator;
A bypass passage formed in the valve body and configured to flow the hydraulic oil supplied from the supply port to the discharge port by bypassing the control valve when the hydraulic actuator is not operated;
In a control valve unit of a work machine, comprising a bypass valve interposed in the bypass flow path and opened when the hydraulic actuator is not operated,
The bypass valve is disposed close to one end of the valve body, and at least one of the supply port and the discharge port is disposed in a section opposite to the one end. Control valve unit for working machines. 2. The control valve unit for a work machine according to claim 1, wherein the at least one port is arranged close to the other end in the longitudinal direction. The control valve unit for a work machine according to claim 2, wherein both the supply port and the discharge port are arranged close to the other end in the longitudinal direction. The valve body includes a body main body and a cover body removably attached to one end in the longitudinal direction of the body main body,
The control valve unit for a work machine according to any one of claims 1 to 3, wherein the bypass valve is incorporated in the cover body. 5. The control valve unit for a work machine according to claim 4, wherein an additional valve can be installed between the body body and the cover body.

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