JP7329316B2 - Valve structures and construction machinery - Google Patents

Description

The present invention relates to a valve structure and construction machinery.

Construction machines such as hydraulic excavators are equipped with hydraulic actuators, and the flow of pressurized oil (i.e. hydraulic oil) supplied to the hydraulic actuators is adjusted by electrically driven solenoid valves or the like (hereinafter also referred to as "electrically driven valves"). can operate the hydraulic actuator. For example, in the hydraulic drive system disclosed in Patent Document 1, the output pressure of an electromagnetic proportional control valve is applied to a directional control valve as a pilot pressure, and the directional control valve supplies a flow rate of oil corresponding to the pilot pressure to the corresponding actuator. do.

JP 2014-142032 A

In a machine equipped with hydraulic actuators, when the flow of pressurized oil is adjusted by electrically driven valves, it is necessary to provide the number of electrically driven valves corresponding to the number of hydraulic actuators. Especially in construction machinery, it is necessary to drive various hydraulic actuators, and the number of electrically driven valves tends to increase. For example, when each of the boom, arm, bucket, swing device, and traveling device of a hydraulic excavator is operated by hydraulic actuators, it is necessary to provide five or more electrically driven valves.

Especially in the field of construction machinery, in recent years, as a control method for hydraulic actuators, there has been a shift from a control method that uses only hydraulic pressure to a combination of control that uses hydraulic pressure (hydraulic control) and control that uses an electrically driven valve (electrical control). It is shifting to a new control method. For example, when changing the drive speed of a hydraulic actuator according to the operation amount of a control lever, conventionally it was necessary to tune the opening of the spool, but when using an electrically driven valve, the drive current can be adjusted. . Thus, it is expected that the demand for the use of electrically driven valves in the control of hydraulic actuators will continue to increase in the future.

The electrically driven valves are controlled by a controller, and the controller supplies a drive current to each electrically driven valve so that each hydraulic actuator can be properly operated. This controller is usually composed of a microcomputer installed in the clean environment of the main body of the machine, and in many cases, one controller (that is, one microcomputer) collectively drives and controls a plurality of electrically driven valves. be. In this case, it is necessary to assume the number and type of electrically driven valves to be used at the stage of designing the controller. In particular, since a drive circuit (output port) for supplying a drive current to the electrically driven valve must be provided for each electrically driven valve, the controller is required to have a number of drive circuits corresponding to the number of electrically driven valves. be done.

On the other hand, conventional controllers that collectively drive and control a plurality of electrically driven valves cannot be provided with an additional drive circuit (output port) later, and the number of electrically driven valves increases. Inability to respond flexibly. In other words, if it is necessary to increase the number of electrically driven valves after designing the controller (especially if the number of drive circuits is insufficient), the existing controller can be replaced with a new controller with an appropriate number of drive circuits, or a new controller can be installed. It is necessary to use such a controller together with an existing controller. Installation of a new controller requires a large amount of cost and requires a review of the device design such as wiring, which is an obstacle to later increasing the number of electrically driven valves.

There is also a demand to additionally mount electrically driven valves on existing machines that do not have controllers. However, as described above, installation of a new controller requires a great deal of labor and cost, which hinders the introduction of a new electrically driven valve to a machine that does not have a controller.

Also, a controller that collectively drives and controls a plurality of electrically driven valves tends to have a more complicated structure and a larger size as the number of electrically driven valves increases. Therefore, as the number of electrically driven valves increases, the structure of the controller becomes complicated and large, the controller itself becomes expensive, and the labor and cost involved in installing the controller also increase.

Thus, a machine in which a single controller collectively drives and controls a plurality of electrically driven valves lacks adaptability to fluctuations in the number of electrically driven valves. Particularly in the field of construction machinery, it is expected that the demand for the use of electrically driven valves will increase in the future, and therefore valve structures that can be flexibly applied to various forms are desired.

SUMMARY OF THE INVENTION The present invention has been made in view of the circumstances described above, and an object thereof is to provide a valve structure applicable to various forms and a technology related to such a valve structure.

One aspect of the present invention includes a valve section, a drive section that drives the valve section according to a drive current, and a valve controller that controls the drive current supplied to the drive section, wherein the valve controller is supported by the drive section. relating to the valve structure.

The drive section may include a movable section that moves along the reference axis in accordance with the drive current, and the valve controller may be provided at a position offset from the drive section in a direction parallel to the reference axis.

The drive section may include a movable section that moves on the reference axis in response to the drive current, and the valve controller may be provided at a position offset from the drive section in a radial direction perpendicular to the reference axis.

The valve controller may be placed in the enclosed space.

The drive may include an electromagnet through which a drive current is passed and a plunger that moves in response to the magnetic force exerted by the electromagnet.

The valve portion may include a spool driven by the drive portion.

The valve controller may supply drive current to the drive section according to a drive signal input from another controller.

The valve controller may supply drive current to the drive section in accordance with the detection signal input from the sensor.

The valve controller may be housed within the valve housing within the radial width of the valve housing housing the drive.

Another aspect of the present invention relates to a construction machine comprising the above valve structure.

ADVANTAGE OF THE INVENTION According to this invention, the valve structure applicable to various forms and the technique relevant to such a valve structure can be provided.

FIG. 1 is a side view showing the outline of the valve structure. FIG. 2 is a block diagram showing the functional configuration of the valve controller. FIG. 3 is a cross-sectional view showing a typical example of the driving section. FIG. 4A is a cross-sectional view showing a schematic configuration of a positive type electromagnetic proportional valve. FIG. 4B is a cross-sectional view showing a schematic configuration of a positive type electromagnetic proportional valve. FIG. 4C is a cross-sectional view showing a schematic configuration of a positive type proportional solenoid valve. FIG. 5A is a cross-sectional view showing a schematic configuration of a negative type electromagnetic proportional valve. FIG. 5B is a cross-sectional view showing a schematic configuration of a negative type electromagnetic proportional valve. FIG. 5C is a cross-sectional view showing a schematic configuration of a negative type electromagnetic proportional valve. FIG. 6 is an external view showing an outline of a typical configuration example of a hydraulic excavator. FIG. 7 is a diagram showing an example of a control mode. FIG. 8 is a diagram showing another example of the control mode. FIG. 9 is a cross-sectional view showing a modification of the drive section.

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a side view showing an outline of the valve structure 10. FIG. The valve structure 10 is configured as an electromagnetic proportional valve comprising a valve portion 15 , a drive portion 16 and a valve controller 17 . The drive unit 16 drives the valve unit 15 according to the drive current to operate the valve unit 15 . The valve controller 17 controls the drive current supplied to the drive section 16 and supplies the drive current to the drive section 16 according to the operation of the valve section 15 .

The valve structure 10 shown in FIG. 1 has a valve housing 20 and a base 21 . The valve housing 20 is provided to extend along the reference axis Ax. The drive unit 16 and the valve controller 17 are accommodated inside the valve housing 20 while being arranged side by side along the reference axis Ax. That is, the valve controller 17 is provided at a position displaced from the drive unit 16 with respect to a direction Dx parallel to the reference axis Ax (hereinafter also referred to as "axial direction"). Thus, the valve controller 17 is housed in the valve housing 20 within the width of the valve housing 20 housing the actuator 16 in the radial direction (i.e., the radial direction) Dr perpendicular to the reference axis Ax. It is possible to prevent the valve structure 10 from increasing in size in the direction Dr. In the illustrated valve structure 10, the movable portion of the driving portion 16 (see reference numeral 25 in FIG. 3, which will be described later) is movably provided on the reference axis Ax, and the valve controller 17 is also positioned on the reference axis Ax. provided above.

The base portion 21 is fixedly connected to one end of the valve housing 20 and extends in the radial direction Dr, and serves as a connection portion for attaching the valve structure 10 to another member. work. For example, a mounting hole (not shown) is formed in the base portion 21, and a fastener such as a screw, bolt, or screw is fitted into the mounting hole to fix the fastener to the base portion 21. The structure 10 can be attached to other members.

The valve controller 17 of this embodiment is supported by the drive section 16 . In the valve structure 10 shown in FIG. 1, each of the actuator 16 and the valve controller 17 is attached to the valve housing 20, and the valve controller 17 is indirectly supported by the actuator 16 via the valve housing 20. . The valve controller 17 may be directly supported by the drive unit 16, or may be supported by, for example, an end position stopper 33 (see FIG. 3), which will be described later. By adopting a structure in which the valve controller 17 is supported by the driving section 16 in the valve structure 10, the driving section 16 and the valve controller 17 can be unitized. As described above, according to the present embodiment, it is possible to provide the valve structure 10 that is compact as a whole while physically integrally providing the elements related to both the driving and the control of the valve portion 15 . Since the valve structure 10 already includes the drive unit 16 and the valve controller 17 necessary for operation in the valve unit 15, the valve structure 10 is excellent in handleability and adaptability, and can be used in various forms as described later. It is possible to flexibly apply

Note that the valve controller 17 shown in FIG. 1 is arranged in the closed space Ss. Specifically, a liquid-tight sealed space Ss is formed in the valve housing 20, and the valve controller 17 is arranged in the sealed space Ss. As a result, liquid such as pressure oil is prevented from entering the sealed space Ss, and the induction of failure of the valve controller 17 can be effectively avoided. In particular, since construction machinery is often used in harsh environments, there is a concern that foreign substances other than pressurized oil (for example, dust, mud, etc.) may scatter and affect the valve controller 17 during use. In relation to this, such concerns can be resolved by arranging the valve controller 17 in the closed space Ss as in the present embodiment.

The degree of sealing of the sealed space Ss is not limited, and based on the actual device configuration and usage environment, the degree of sealing of the sealed space Ss to the extent that it is possible to effectively prevent troubles in the valve controller 17 due to foreign matter such as pressure oil. It is preferable to have Therefore, from the viewpoint of preventing moisture and pressure oil components drifting in the atmosphere from entering the sealed space Ss, the sealed space Ss may be provided airtightly to prevent outside air from entering the sealed space Ss. In practice, however, there are cases where it is preferable to take outside air into the closed space Ss from the viewpoint of temperature control. Therefore, it is preferable that the degree of sealing of the sealed space Ss is determined by comprehensively considering various requirements.

The space inside the valve housing 20 in which the driving portion 16 is arranged may be filled with oil such as pressure oil. In that case, it is preferable to provide a seal structure that prevents oil from leaking out from the space in the valve housing 20 in which the driving portion 16 is arranged.

Next, a typical example of the valve controller 17 will be described.

FIG. 2 is a block diagram showing the functional configuration of the valve controller 17. As shown in FIG. Each functional block of the valve controller 17 can be implemented by arbitrary hardware and/or software, and for example two or more functional blocks may be implemented by a single piece of hardware/software. Also, the valve controller 17 may have a functional configuration different from that shown in FIG. For example, the input unit 53 may input and output various information with the sensor 73 and other controllers 72 via communication means such as CAN communication.

The valve controller 17 shown in FIG. 2 includes a processing section 51 , a storage section 52 , an input section 53 , a drive current supply section 54 and an output section 55 .

The processing unit 51 is a processing device that performs calculations based on various types of information and outputs calculation results, and can be configured by an arithmetic circuit such as a CPU (Central Processing Unit), for example. The storage unit 52 is a memory device that stores various data, and writes and reads data as required, and can be configured by an EEPROM or the like, for example. The processing unit 51 receives information via the input unit 53 or the like, reads information from the storage unit 52 and/or writes information to the storage unit 52 as necessary, and supplies the information to the drive current supply unit 54 and the output unit 55. to output "Information" handled by the valve controller 17 is interpreted in a broad sense, and is a concept that can include various data such as numerical values, instructions (commands) to other devices, and other information.

The input unit 53 functions as an input interface unit for the valve controller 17, is connected to the processing unit 51, and is connected to various external devices. The input unit 53 provides input information to the processing unit 51 according to a signal input from the connected external device. External devices that can be connected to the input unit 53 are not limited, but other controllers 72 and/or sensors 73 can be connected to the input unit 53 in this embodiment. For example, the other controller 72 may send a drive signal to the input section 53 to instruct the supply of drive current to the drive section 16 and the magnitude of the drive current. An integrated controller (see reference numeral "18" in FIG. 7), which will be described later, can correspond to the "other controller 72" referred to here. The sensor 73 detects predetermined information and inputs a detection signal indicating the detection result to the input unit 53 . Sensor 73 is capable of detecting any information needed to determine the supply of drive current to drive 16 and the magnitude of that drive current, e.g. The flow rate and/or pressure of pressurized oil in the passage may be detected.

The output unit 55 functions as an output interface unit of the valve controller 17, is connected to the processing unit 51, and is connected to various external devices. The output unit 55 outputs a signal containing various information to an external device according to the information from the processing unit 51 . The output section 55 shown in FIG. 2 includes an information output section 56 connected to the display device 74 and an abnormality output section 57 connected to the alarm device 75 . The information output unit 56 transmits a signal including data input to the processing unit 51 and/or data derived by the processing unit 51 to the display device 74 . The display device 74 displays various information according to signals from the information output section 56 . The abnormality output unit 57 transmits an output signal indicating the detected abnormality to the alarm device 75 when an abnormality is detected from the data input to the processing unit 51 and/or the data derived by the processing unit 51. The process of detecting such an abnormality may be performed by the processing unit 51 or may be performed by the abnormality output unit 57 . Based on the signal from the abnormality output unit 57, the alarm device 75 issues an alarm such as display or sound indicating an abnormality as necessary.

The drive current supply unit 54 supplies drive current to the drive unit 16 according to information from the processing unit 51 . The processing unit 51 directly or indirectly determines the magnitude of the drive current required to drive the valve unit 15 based on data input from the other controller 72 and/or the sensor 73 via the input unit 53. to derive The drive current supply unit 54 supplies a drive current to the drive unit 16 according to the result of this derivation by the processing unit 51, and a desired magnitude of drive current is applied to the drive unit 16. FIG. The drive current is energy for driving the drive section 16 (especially the movable section 25), and the drive current supply section 54 uses electricity from the power supply 71 connected to the valve controller 17 to generate the desired drive current. is supplied to the drive unit 16 .

In this manner, the valve controller 17 can supply drive current to the drive section 16 according to the drive signal input from the other controller 72 . The valve controller 17 can also supply drive current to the drive section 16 according to the detection signal input from the sensor 73 .

Next, a typical example of the driving section 16 will be described.

FIG. 3 is a cross-sectional view showing a typical example of the driving section 16. As shown in FIG. Although FIG. 3 shows the drive unit 16 configured by a so-called push-type solenoid actuator, the drive method and configuration of the drive unit 16 are not limited. Accordingly, an actuator 16 employing, for example, a pull-type actuation scheme may be used in the valve structure 10 described above.

The driving portion 16 includes a movable portion 25 that moves along the reference axis Ax according to the driving current. Specifically, the drive unit 16 includes an electromagnet 27 through which drive current supplied from the valve controller 17 flows, and a plunger 28 that moves according to the magnetic force produced by the electromagnet 27 .

The movable portion 25 shown in FIG. 3 includes a plunger 28, a push rod 30 fixedly attached to one end of the plunger 28 (the right end in FIG. 3), and the other end of the plunger 28. and a spring stop 32 fixedly attached to the part (the left end in FIG. 3). The spring stopper 32 , the plunger 28 and the push rod 30 are arranged side by side along the reference axis Ax, and are integrally movable in the axial direction Dx according to the magnetic force of the electromagnet 27 .

The electromagnet 27 is composed of a solenoid coil, and in the drive unit 16 shown in FIG. ing. The drive housing 26 may be configured by a part of the valve housing 20 or may be configured separately from the valve housing 20 . Integral spring stop 32 , plunger 28 and push rod 30 are generally mounted through drive housing 26 , but spring stop 32 is located outside drive housing 26 . Plunger 28 and push rod 30 , on the other hand, are located partially inside drive housing 26 . In addition to the spring stopper 32, an end position stopper 33 and a spring 29, which will be described later, are located outside the drive housing 26 in FIG. 3, but are located inside the valve housing 20 (see FIG. 1).

A plunger stopper 31 is attached to the drive housing 26 . The plunger stopper 31 is provided to extend toward the inside of the drive housing 26 in the axial direction Dx (especially the opposite axial direction Dx2), and has a through hole extending along the reference axis Ax. The push rod 30 is arranged in this through hole, passes through the plunger stopper 31 , and is provided so as to be reciprocally movable in the axial direction Dx without being blocked by the plunger stopper 31 . The plunger 28 side end (left end in FIG. 3) of the plunger stopper 31 has a shape corresponding to the shape of the plunger 28 . In the driving portion 16 shown in FIG. 3, the end portion of the plunger 28 on the plunger stopper 31 side (the right end portion in FIG. 3) has a tapered shape, and the end portion of the plunger stopper 31 on the plunger 28 side has a tapered shape. A concave portion having a tapered surface is formed at (the left end portion in FIG. 3). By engaging the plunger 28 with the recessed portion of the plunger stopper 31, the movement of the plunger 28 in the axial direction Dx (especially the forward axial direction Dx1) is restricted. Thus, the plunger stopper 31 functions as a member that guides the push rod 30 and also functions as a member that limits the movement of the plunger 28 (that is, the movable portion 25).

A spring 29 in compression is arranged between the spring stop 32 and the drive housing 26 . The spring 29 imparts elastic force to the spring stopper 32 and the drive housing 26 so as to increase the distance between the spring stopper 32 and the drive housing 26 (especially the distance in the axial direction Dx).

When the electromagnet 27 is energized by the valve controller 17 , the plunger 28 is retracted into the drive housing 26 . That is, the plunger 28 is attracted to the electromagnet 27 by magnetic force and moves in the axial direction Dx (especially the forward axial direction Dx1). At this time, the spring 29 is compressed between the spring stopper 32 and the drive housing 26, and the elastic force applied from the spring 29 to the spring stopper 32 and the drive housing 26 increases. Therefore, when the plunger 28 and the plunger stopper 31 are not in contact with each other, the movable portion 25 (ie, the spring stopper 32 , the plunger 28 and the push rod 30 ) has the elastic force applied by the spring 29 and the electromagnet 27 . It is placed at a position where the magnetic force applied is balanced. Therefore, when no drive current is supplied to the electromagnet 27, no magnetic force is applied to the plunger 28, and the movable part 25 receives the elastic force of the spring 29 and is positioned relatively to the left in FIG. , the amount of protrusion of the push rod 30 is relatively small. On the other hand, when a drive current is applied to the electromagnet 27, a magnetic force is applied to the plunger 28, the movable portion 25 is arranged relatively to the right in FIG. become significantly larger.

An end position stopper 33 is fixedly provided on the opposite side of the spring 29 via the spring stopper 32 . For example, the end position stop 33 may be fixedly supported by the valve housing 20 . The contact of the spring stopper 32 with the end position stopper 33 restricts the movement of the spring stopper 32 (that is, the movement in the opposite axial direction Dx2). 28 movement (ie movement in the forward axis direction Dx1) is restricted. Accordingly, the position of the end position stopper 33 determines the minimum amount of protrusion of the push rod 30 from the drive housing 26, and the position of the plunger stopper 31 determines the maximum amount of protrusion of the push rod 30 from the drive housing 26. quantity can be determined.

Also, a heat insulator (not shown) is preferably provided between the drive unit 16 (especially the electromagnet 27 shown in FIG. 3) and the valve controller 17, and such a heat insulator is fixed by the valve housing 20, for example. may be supported. In this case, the heat generated by the valve controller 17 can be prevented from being transferred to the driving section 16 , and the heat generated by the driving section 16 can be prevented from being transferred to the valve controller 17 .

Next, a typical example of the valve portion 15 will be described.

A case where the valve portion 15 is configured by an electromagnetic proportional valve for supplying pressure oil at a desired pressure to the hydraulic actuator will be exemplified below, but the configuration and function of the valves that configure the valve portion 15 are not limited.

An electromagnetic proportional valve that can control the supply pressure of pressure oil according to a drive current (that is, an excitation current) is connected to a hydraulic device such as a hydraulic actuator, and supplies pressure oil at a desired pressure to the hydraulic device. Note that the pressure oil referred to here is not necessarily limited to oil such as mineral oil, but is a concept that can include general fluids (especially liquids) that can be used as an energy transmission medium. In general, the types of proportional solenoid valves include positive type proportional solenoid valves and negative type proportional solenoid valves. Electromagnetic proportional valves in which the output hydraulic pressure (that is, hydraulic pressure) increases as the drive current increases are classified as positive type electromagnetic proportional valves, while those in which the output hydraulic pressure decreases are negative. It is classified as a type of solenoid proportional valve.

As the valve portion 15 described above, both a positive type electromagnetic proportional valve and a negative type electromagnetic proportional valve can be employed. A valve portion 15 exemplified below is constituted by a spool type electromagnetic proportional valve, and is provided with a spool driven by a driving portion 16 . First, the positive type valve portion 15 will be described, and then the negative type valve portion 15 will be described.

[Positive type valve part]
4A to 4C are sectional views showing a schematic configuration of the positive type valve portion 15. FIG. FIG. 4A shows a non-excited state in which no drive current is applied to the drive section 16. FIG. FIG. 4B shows a state in which a relatively small drive current is applied to the drive portion 16 and the spool body 112 is placed in a neutral position. FIG. 4C shows a state in which a relatively large drive current is applied to drive section 16 .

The valve portion 15 shown in FIGS. 4A to 4C includes a valve body 111, a spool body 112 and a pressing portion 114. FIG. The valve body 111 has a valve hole 121 extending in the axial direction Dx, and an inlet port 131 , an outlet port 132 , a drain port 133 and an output port 134 that open to the valve hole 121 . The inlet port 131 communicates with a hydraulic source P that supplies pressure oil, and the outlet port 132 communicates with a drainage portion T that discharges the pressure oil. The drain port 133 communicates with a drain portion through which pressure oil is discharged. In the valve section 15 shown in FIGS. 4A to 4C, the drainage section T functions as a drain section, and the outlet port 132 and the drain port 133 communicate with a common drainage section T (ie, drain section). The output port 134 communicates with the hydraulic actuator A to which pressure oil is supplied. A specific configuration of the hydraulic actuator A is not limited, and typically the hydraulic actuator A is configured by a hydraulic cylinder or a hydraulic motor.

The valve hole 121 includes a large-diameter hole portion 122 having a first diameter H1 in the radial direction Dr perpendicular to the axial direction Dx, and a small-diameter hole portion 122 having a second diameter H2 smaller than the first diameter H1 in the radial direction Dr. and a portion 123 . The large-diameter hole portion 122 is provided adjacent to the small-diameter hole portion 123 and arranged on the forward axial direction Dx1 side of the small-diameter hole portion 123 . One end side of the spool body 112 is arranged in the large diameter hole portion 122 , and the other end side of the spool body 112 is arranged in the small diameter hole portion 123 . Although not clearly shown in FIGS. 4A to 4C, each of the large diameter hole portion 122 and the small diameter hole portion 123 forms a closed space filled with pressure oil supplied from the hydraulic source P. . The large diameter hole portion 122 communicates with the hydraulic actuator A through the output port 134 .

A drain space 124, which is a space surrounded by the small-diameter spool portion 146, the large-diameter spool portion 147, and the valve body 111 in the large-diameter hole portion 122, varies in volume depending on the position of the spool body 112 in the axial direction Dx. It communicates with the drain port 133 regardless of the position of the main body 112 in the axial direction Dx. Therefore, regardless of the position of the spool body 112 in the axial direction Dx, the pressure oil in the drain space 124 flows out to the drainage portion T through the drain port 133, and the valve body 111 and the spool body 112 are in the drain space 124. Do not receive pressure from pressurized oil.

The spool body 112 is arranged in the valve hole 121 so as to be movable in the axial direction Dx. One end side of the spool body 112 is arranged in the large diameter hole portion 122 , and the other end side of the spool body 112 is arranged in the small diameter hole portion 123 . A large diameter spool portion 147 having an outer diameter corresponding to the diameter of the large diameter hole portion 122 is provided on one end side of the spool body 112 arranged in the large diameter hole portion 122 . A small diameter spool portion 146 having an outer diameter corresponding to the diameter of the small diameter hole portion 123 is provided on the other end side of the spool body 112 arranged in the small diameter hole portion 123 .

The large-diameter spool portion 147 is in close contact with the inner wall surface of the valve body 111 (in particular, the inner wall surface forming the large-diameter hole portion 122) to the extent that the spool body 112 is allowed to move in the axial direction Dx. The small-diameter spool portion 146 is in close contact with the inner wall surface of the valve body 111 (in particular, the inner wall surface forming the small-diameter hole portion 123) to the extent that the spool body 112 is allowed to move in the axial direction Dx. However, the pressure oil in the valve hole 121 basically does not pass between the large diameter spool portion 147 and the valve main body 111 and between the small diameter spool portion 146 and the valve main body 111 .

The spool body 112 has a spool hole 141 extending in the axial direction Dx, and a communication hole 142, an outlet hole 143, an inlet hole 144 and a control hole 145 that open to the spool hole 141. In this embodiment, a communication hole 142 and a control hole 145 are formed at both ends of the spool body 112, respectively, and an outlet hole 143 and an inlet hole 144 are formed between the communication hole 142 and the control hole 145 in the spool body 112. formed in the part of

The communication hole 142, the exit hole 143 and the entrance hole 144 are open in the radial direction Dr. In particular, the communication hole 142 opens into the small diameter hole portion 123 and allows the small diameter hole portion 123 and the spool hole 141 to communicate with each other regardless of the position of the spool body 112 in the axial direction Dx. Depending on the position of the spool body 112 in the axial direction Dx, the outlet hole 143 opens toward the outlet port 132 or the inner wall surface of the valve body 111 (in particular, the inner wall surface forming the large diameter hole portion 122). opens toward the inlet port 131 or the inner wall surface of the valve body 111 (in particular, the inner wall surface forming the large-diameter hole portion 122).

On the other hand, the control hole 145 opens in the axial direction Dx (forward axial direction Dx1 in FIGS. 4A to 4C) and communicates with the output port 134 via the valve hole 121 (especially the large diameter hole portion 122). The large diameter hole portion 122 connected to the hydraulic actuator A through the output port 134 is connected to the spool hole 141 through one of the communication hole 142 and the control hole 145 (“control hole 145” in FIGS. 4A to 4C). communicate with. The small-diameter hole portion 123 communicates with the spool hole 141 through the other of the communication hole 142 and the control hole 145 (“communication hole 142” in FIGS. 4A to 4C). Therefore, the large-diameter hole portion 122 and the small-diameter hole portion 123 of the valve hole 121 communicate with each other through the spool hole 141, the communication hole 142 and the control hole 145. The pressure of the pressure oil inside the hole 123 and the pressure of the pressure oil inside the valve hole 121 are equal to each other.

The movable portion 25 (especially the push rod 30) of the driving portion 16 presses the spool body 112 in the forward axial direction Dx1, and the pressing force on the spool body 112 is variable according to the drive current applied by the valve controller 17.

The pressing portion 114 presses the spool body 112 (the large diameter spool portion 147 in this embodiment) in the opposite axial direction Dx2. The force applied from the pressing portion 114 to the spool body 112 varies depending on the position of the spool body 112 in the axial direction Dx. The force applied increases.

In the positive type valve portion 15 having the above-described configuration, a pressure receiving area difference is provided between both end portions of the spool body 112, and the hydraulic force, the driving force of the driving portion 16, and the pressing portion 114 resulting from this pressure receiving area difference are By mutually balancing the pressing forces of , a desired pressure of pressurized oil can be delivered from the control hole 145 to the hydraulic actuator A. As shown in FIG. That is, the surface area of the spool body 112 that receives force in the forward axial direction Dx1 from the pressure oil filled in the valve hole 121 and the spool hole 141 is different from the surface area of the spool body 112 that receives force in the reverse axial direction Dx2 from the pressure oil. ing. Specifically, the surface area of the spool body 112 that receives the force from the pressure oil in the reverse axial direction Dx2 is larger than the surface area of the spool body 112 that receives the force from the pressure oil in the forward axial direction Dx1.

Therefore, the force F1 exerted by the pressurized oil on the spool body 112 in the forward axial direction Dx1 is different from the force F2 exerted by the pressurized oil on the spool body 112 in the reverse axial direction Dx2, as shown in FIGS. 4A to 4C. In the valve portion 15, a relationship of "F1<F2" is established. Therefore, the spool body 112 receives force in the reverse axial direction Dx2 from the pressure oil filled in the valve hole 121 and the spool hole 141 . Specifically, a force F0 derived from "F0=F2-F1" acts on the spool body 112 from the pressure oil in the opposite axial direction Dx2.

The spool body 112 also receives force from the push rod 30 of the drive section 16 and the pressing section 114 . The pressure of the pressure oil in the valve hole 121 and the spool hole 141 is represented by "Ph". The difference between the surface area S2 of the spool body 112 that receives the force in the reverse axial direction Dx2 from the pressure oil and the surface area S2 is represented by "Up (= S2 - S1)", and the force that the drive unit 16 imparts to the spool body 112 in the forward axial direction Dx1 is When the force applied to the spool body 112 in the opposite axial direction Dx2 by the pressing portion 114 is represented by "Fd" and represented by "Fsp", the following relational expression 1 is established.

[Relational Expression 1] Fd=Ph×Up+Fsp

In the actual valve unit 15, the above "Up" is basically set to a fixed value. Further, the above "Fsp" is a value within a certain range in the valve portion 15 of the present embodiment, in which pressure oil is supplied to and discharged from the spool hole 141 and the valve hole 121 according to the position of the spool body 112 in the axial direction Dx. take. Therefore, as is clear from the above relational expression 1, as the force "Fd" applied from the drive unit 16 to the spool body 112 increases, the pressure "Ph ” also increases. Therefore, the valve controller 17 controls the drive current value applied to the drive unit 16 and adjusts the force (Fd) applied by the drive unit 16 to the spool main body 112, thereby supplying pressurized oil having a desired pressure to the control hole. 145 to the hydraulic actuator A via the large-diameter hole 122 and the output port 134 .

Next, the behavior of the positive type valve portion 15 described above will be described.

When no current is applied to drive portion 16 or when a first drive current is applied to drive portion 16, spool body 112 is disposed in the first position shown in FIG. 4A. In this case, the spool hole 141 communicates with the outlet port 132 through the outlet hole 143, and the pressure of the pressure oil in the spool hole 141 and the pressure oil in the valve hole 121 decreases.

Further, when a second current larger than the first drive current is applied to the driving portion 16, the spool body 112 is pushed in the forward axial direction Dx1 by the push rod 30 of the driving portion 16, causing the second driving current shown in FIG. position. In this case, the spool hole 141 communicates with the inlet port 131 through the inlet hole 144, and the pressure oil from the hydraulic source P is supplied to the spool hole 141. The pressure of the pressurized oil increases. As described above, in the valve portion 15 of the present embodiment, the spool body 112 (see FIG. 4A) arranged at the first position is more reversed than the spool body 112 (see FIG. 4C) arranged at the second position. It is located on the axial direction Dx2 side.

Also, when a third current greater than the first drive current and less than the second current is applied to the drive portion 16, the spool body 112 is in the third position (ie, neutral position) shown in FIG. 4B. placed. In this case, outlet hole 143 does not communicate with outlet port 132 and inlet hole 144 does not communicate with inlet port 131 . As a result, the spool hole 141 is blocked from both the inlet port 131 and the outlet port 132, and the pressure of the pressure oil in the spool hole 141 and the pressure oil in the valve hole 121 is basically maintained without decreasing or increasing. be.

Thus, in the positive type valve portion 15, when the drive current applied to the drive portion 16 is small and the thrust of the push rod 30 is zero (0) or weak, the pressure oil in the valve hole 121 and the spool hole 141 is The amount of oil discharged to the drainage portion T increases, and the pressure of the pressure oil in the valve hole 121 and the spool hole 141 decreases. On the other hand, when the drive current applied to the drive unit 16 is large and the thrust of the push rod 30 is strong, the amount of pressurized oil supplied from the hydraulic pressure source P into the valve hole 121 and the spool hole 141 increases. The pressure of the pressurized oil inside and inside the spool hole 141 increases. When the driving current applied to the driving portion 16 is in the intermediate range and the spool body 112 is arranged at the neutral position shown in FIG. T is cut off, and the supply and discharge of pressure oil to the inside of the valve hole 121 and the inside of the spool hole 141 are stopped.

The positive type valve portion 15 exhibiting the above behavior sends pressure oil of a desired pressure from the control hole 145 according to the following mechanism.

That is, the valve controller 17 (especially the drive current supply section 54) applies a drive current of a predetermined value to the drive section 16 according to the desired pressure of the pressure oil. As a result, the push rod 30 of the drive unit 16 moves the spool body 112 in the forward axial direction Dx1 and places it in the second position (see FIG. 4C), thereby blocking the connection between the outlet hole 143 and the outlet port 132. Together, the inlet hole 144 is communicated with the inlet port 131 . Therefore, the pressure oil from the hydraulic source P is supplied to the spool hole 141 and the valve hole 121, and the pressure of the pressure oil in the spool hole 141 and the valve hole 121 increases.

Then, when the pressure of the pressure oil in the spool hole 141 and the valve hole 121 becomes greater than the desired pressure while the magnitude of the drive current applied to the drive unit 16 is maintained, the spool body 112 moves in the opposite axial direction Dx2. to be placed in the first position (see FIG. 4A). As a result, the inlet hole 144 and the inlet port 131 are blocked, the outlet hole 143 communicates with the outlet port 132, and the pressure of the pressure oil in the spool hole 141 and the valve hole 121 is reduced.

Then, when the pressure of the pressure oil in the spool hole 141 and the valve hole 121 becomes smaller than the desired pressure while the magnitude of the drive current applied to the drive unit 16 is maintained, the spool body 112 moves forward in the forward axial direction Dx1. , and again placed in the second position (see FIG. 4C). As a result, the outlet hole 143 and the outlet port 132 are blocked, the inlet hole 144 is communicated with the inlet port 131, and the pressure of the pressure oil in the spool hole 141 rises again.

In this way, the spool body 112 is positioned at the second position (see FIG. 4C) while the driving current of a predetermined value corresponding to the desired pressure of the hydraulic oil is continuously applied to the driving portion 16. By repeatedly moving to and from the first position (see FIG. 4A), pressurized oil is repeatedly supplied to and discharged from the spool hole 141 . As a result, the pressure of the pressure oil in the spool hole 141 and the valve hole 121 is maintained at the desired pressure, and the pressure oil at the desired pressure flows out from the control hole 145 and is supplied to the hydraulic actuator A.

[Negative type solenoid proportional valve]
In the negative type valve portion 15 described below, the same or similar configurations as those of the positive type valve portion 15 (see FIGS. 4A to 4C) are denoted by the same reference numerals, and detailed description thereof will be omitted. .

5A to 5C are sectional views showing a schematic configuration of the negative type valve portion 15. FIG. 5A shows a non-excited state in which no drive current is applied to the drive section 16, FIG. 5B shows a state in which the spool body 112 is placed in a neutral position, and FIG. It shows a state in which a relatively large drive current is flowing.

The small-diameter hole portion 123 of the valve hole 121 of the present embodiment is provided adjacent to the large-diameter hole portion 122 and arranged on the forward axial direction Dx1 side of the large-diameter hole portion 122 . Although not clearly shown in FIGS. 5A to 5C, each of the large-diameter hole portion 122 and the small-diameter hole portion 123 forms a closed space filled with pressure oil supplied from the hydraulic source P. . The small diameter hole portion 123 communicates with the hydraulic actuator A through the output port 134 .

One end side of the spool body 112 is arranged in the large diameter hole portion 122 , and the other end side of the spool body 112 is arranged in the small diameter hole portion 123 . A large diameter spool portion 147 having an outer diameter corresponding to the diameter of the large diameter hole portion 122 is provided on one end side of the spool body 112 arranged in the large diameter hole portion 122 . A small diameter spool portion 146 having an outer diameter corresponding to the diameter of the small diameter hole portion 123 is provided on the other end side of the spool body 112 arranged in the small diameter hole portion 123 .

A control hole 145 is formed in one of the one end side and the other end side of the spool body 112, and a communication hole 142 is formed in the other. An outlet hole 143 and an inlet hole 144 are formed in the small diameter spool portion 146 of the spool body 112 .

The communication hole 142 opens into the large-diameter hole portion 122 and allows the large-diameter hole portion 122 and the spool hole 141 to communicate with each other regardless of the position of the spool body 112 in the axial direction Dx. Depending on the position of the spool body 112 in the axial direction Dx, the outlet hole 143 opens toward the outlet port 132 or the inner wall surface of the valve body 111 (in particular, the inner wall surface forming the small-diameter hole portion 123). It opens toward the inlet port 131 or the inner wall surface of the valve body 111 (in particular, the inner wall surface forming the small-diameter hole portion 123).

The control hole 145 opens in the forward axial direction Dx1 and communicates with the output port 134 via the valve hole 121 (especially the small diameter hole portion 123). In this way, the small-diameter hole portion 123 connected to the hydraulic actuator A through the output port 134 is through one of the communication hole 142 and the control hole 145 ("control hole 145" in FIGS. 5A to 5C), It communicates with the spool hole 141 . Also, the large-diameter hole portion 122 communicates with the spool hole 141 through the other of the communication hole 142 and the control hole 145 (“communication hole 142” in FIGS. 5A to 5C). Therefore, the large-diameter hole portion 122 and the small-diameter hole portion 123 communicate with each other through the spool hole 141, the communication hole 142 and the control hole 145. and the pressure of the pressure oil in the spool hole 141 become equal to each other.

The movable portion 25 (especially the push rod 30) of the drive portion 16 presses the spool body 112 in the forward axial direction Dx1, and the pressing force against the spool body 112 is variable according to the drive current. The pressing portion 114 presses the spool body 112 (the small diameter spool portion 146 in this embodiment) in the opposite axial direction Dx2.

In the above-described negative type valve portion 15 as well, a pressure receiving area difference is provided between both ends of the spool body 112, and the hydraulic force, the driving force of the driving portion 16, and the pressing force of the pressing portion 114 resulting from this pressure receiving area difference are By mutually balancing the forces, the desired pressure of pressurized oil can be delivered from the control hole 145 towards the hydraulic actuator A.

That is, the surface area of the spool body 112 that receives force in the forward axial direction Dx1 from the pressure oil filled in the valve hole 121 and the spool hole 141 is different from the surface area of the spool body 112 that receives force in the reverse axial direction Dx2 from the pressure oil. ing. Specifically, the surface area of the spool body 112 that receives the force in the forward axial direction Dx1 from the pressure oil is larger than the surface area of the spool body 112 that receives the force in the reverse axial direction Dx2 from the pressure oil.

Therefore, the force F1 exerted by the pressurized oil on the spool body 112 in the forward axial direction Dx1 is different from the force F2 exerted by the pressurized oil on the spool body 112 in the reverse axial direction Dx2, as shown in FIGS. 5A to 5C. In the valve portion 15, a relationship of "F1>F2" is established. Therefore, the spool body 112 receives force in the forward axial direction Dx1 from the pressure oil filled in the valve hole 121 and the spool hole 141 . Specifically, a force F0 derived from "F0=F1-F2" acts on the spool body 112 from the pressurized oil in the forward axial direction Dx1.

The pressure of the pressure oil in the valve hole 121 and the spool hole 141 is represented by "Ph". The difference between the surface area S2 of the spool body 112 that receives the force in the reverse axial direction Dx2 from the pressure oil and the surface area S2 is represented by "Un (= S1 - S2)", and the force that the drive unit 16 imparts to the spool body 112 in the forward axial direction Dx1 is When the force applied by the pressing portion 114 to the spool main body 112 in the opposite axial direction Dx2 is represented by "Fd" and represented by "Fsp", the following relational expression 2 is established.

[Relational expression 2] Fd=Fsp-Ph×Un

In the actual valve unit 15, the above "Un" is basically set to a fixed value. Further, the above "Fsp" is a value within a certain range in the valve portion 15 of the present embodiment, in which pressure oil is supplied to and discharged from the spool hole 141 and the valve hole 121 according to the position of the spool body 112 in the axial direction Dx. take. Therefore, as is clear from the above relational expression 2, as the force "Fd" applied from the drive unit 16 to the spool body 112 increases, the pressure "Ph ” is reduced. Therefore, by controlling the driving current value applied to the driving portion 16 by the valve controller 17 and adjusting the force (Fd) applied by the driving portion 16 to the spool main body 112, pressurized oil having a desired pressure can be supplied to the control hole. 145 to the hydraulic actuator A via the small-diameter hole 123 and the output port 134 .

Next, the behavior of the negative type valve portion 15 described above will be described.

When no current is applied to drive portion 16 or when a first drive current is applied to drive portion 16, spool body 112 is disposed in the first position shown in FIG. 5A. In this case, the spool hole 141 communicates with the inlet port 131 through the inlet hole 144, and the pressure of the pressure oil in the spool hole 141 and the pressure oil in the valve hole 121 increases.

Further, when a second current larger than the first drive current is applied to the drive portion 16, the spool body 112 is pushed in the forward axial direction Dx1 by the push rod 30 of the drive portion 16, causing the second drive current shown in FIG. position. In this case, the spool hole 141 communicates with the outlet port 132 through the outlet hole 143, and the pressure of the pressure oil in the spool hole 141 and the pressure oil in the valve hole 121 decreases. In addition, in the valve portion 15 of the present embodiment, the spool body 112 (see FIG. 5A) arranged at the first position is arranged in the opposite axial direction than the spool body 112 (see FIG. 5C) arranged at the second position. Located on the Dx2 side.

Also, when a third current greater than the first drive current and less than the second current is applied to the drive portion 16, the spool body 112 is positioned at the third position shown in FIG. 5B. In this case, the outlet hole 143 does not communicate with the outlet port 132 and the inlet hole 144 does not communicate with the inlet port 131, and the pressure of the pressure oil in the spool hole 141 and the pressure oil in the valve hole 121 basically decreases. maintained without increasing.

Thus, in the negative type valve portion 15, when the drive current applied to the drive portion 16 is small and the thrust of the push rod 30 is zero (0) or weak, the pressure from the hydraulic pressure source P to the valve hole 121 and the spool hole 141 is reduced. , the pressure of the pressure oil in the valve hole 121 and the spool hole 141 increases. On the other hand, when the driving current applied to the driving portion 16 is large and the thrust of the push rod 30 is strong, the amount of pressure oil discharged from the valve hole 121 and the spool hole 141 to the drain portion T increases. The pressure of the pressurized oil inside 121 and inside the spool hole 141 decreases. When the driving current applied to the driving portion 16 is in the intermediate range and the spool body 112 is arranged at the neutral position shown in FIG. The flow path between T is blocked. As a result, the supply and discharge of pressure oil to and from the valve hole 121 and the spool hole 141 are stopped, and the pressure of the pressure oil in the valve hole 121 and the spool hole 141 is maintained.

The negative type valve portion 15 exhibiting the above-described behavior sends pressure oil at a desired pressure from the control hole 145 according to the following mechanism.

That is, in a state in which the inside of the valve hole 121 and the inside of the spool hole 141 are filled with pressure oil, a drive current having a predetermined value is applied to the driving portion 16 according to the desired pressure of the pressure oil. As a result, the push rod 30 of the drive unit 16 moves the spool body 112 in the forward axial direction Dx1 and places it in the second position (see FIG. 5C), thereby blocking the connection between the inlet hole 144 and the inlet port 131. In addition, the outlet hole 143 communicates with the outlet port 132 . As a result, the pressure of the pressure oil in the spool hole 141 and the valve hole 121 is lowered.

When the pressure of the pressure oil in the spool hole 141 and the valve hole 121 becomes smaller than the desired pressure while the magnitude of the drive current applied to the drive unit 16 is maintained, the spool main body 112 moves in the opposite axial direction Dx2. to be placed in the first position (see FIG. 5A). As a result, the outlet hole 143 and the outlet port 132 are blocked, the inlet hole 144 is communicated with the inlet port 131, and pressure oil from the hydraulic pressure source P is supplied to the spool hole 141 and the valve hole 121. The pressure of the pressure oil inside 141 and inside the valve hole 121 increases.

Then, when the pressure of the pressure oil in the spool hole 141 and the valve hole 121 becomes greater than the desired pressure while the magnitude of the drive current applied to the drive unit 16 is maintained, the spool body 112 moves forward in the forward axial direction Dx1. , the inlet hole 144 and the inlet port 131 are blocked and the outlet hole 143 communicates with the outlet port 132 . As a result, the pressure of the pressure oil in the spool hole 141 and the valve hole 121 drops again.

In this way, the spool body 112 is positioned at the second position (see FIG. 5C) while the driving current of a predetermined value corresponding to the desired pressure of the hydraulic oil is continuously applied to the driving portion 16. By repeatedly moving to and from the first position (see FIG. 5A), pressurized oil is repeatedly supplied to and discharged from the spool hole 141 . As a result, the pressure of the pressure oil in the spool hole 141 and the valve hole 121 is maintained at the desired pressure, and the pressure oil at the desired pressure flows out from the control hole 145 and is supplied to the hydraulic actuator A.

[Application example]
The valve structure 10 described above can be mounted on various machines, and can be suitably mounted on construction machines such as hydraulic excavators in particular.

FIG. 6 is an external view showing an outline of a typical configuration example of the hydraulic excavator 210. As shown in FIG. Hydraulic excavator 210 generally includes a lower frame 244 having crawlers, an upper frame 245 provided pivotable with respect to lower frame 244, a boom 247 attached to upper frame 245, and an arm 248 attached to boom 247. , and a bucket 249 attached to an arm 248 . Hydraulic cylinders 267, 268, and 269 as actuators are hydraulic cylinders for boom, arm, and bucket, and drive boom 247, arm 248, and bucket 249, respectively. Rotational driving force from the turning motor 246 is transmitted to the upper frame 245 so that the upper frame 245 is turned by the turning motor 246 . Rotational driving force from the travel motor 251 is transmitted to the crawler of the lower frame 244 so that the crawler is driven by the travel motor 251 and the hydraulic excavator 210 travels.

In this hydraulic excavator 210, each of the hydraulic cylinders 267, 268, 269, swing motor 246 and traveling motor 251 corresponds to the hydraulic actuator A shown in FIGS. 4A to 5C. Therefore, a plurality of valve structures 10 corresponding to each of the hydraulic cylinders 267, 268, 269, swing motor 246 and travel motor 251 can be installed at appropriate locations in the oil passage. In this case, pressure oil of a desired pressure can be supplied to each of the hydraulic cylinders 267, 268, 269, swing motor 246 and travel motor 251.

Next, a typical example of a control configuration using the valve structure 10 described above will be described. The valve structure 10 comprising the actuator 16 and the valve controller 17 as described above can be applied in various forms.

For example, as shown in FIG. 7, a plurality of valve controllers 17 may be connected to an integrated controller 18, and these valve controllers 17 may be controlled by the integrated controller 18. In this case, since each valve controller 17 has a drive current supply section 54 , the integrated controller 18 does not have to have the drive current supply section 54 . Therefore, even when connecting a new valve structure 10 (valve controller 17 ) to the existing integrated controller 18 , there is no need to add the drive current supply section 54 to the existing integrated controller 18 . Therefore, it is possible to newly introduce the above-described valve structure 10 to an existing machine simply and at low cost.

Further, as shown in FIG. 8, a plurality of valve controllers 17 may be connected to each other through wiring N. In this case, even if the integrated controller 18 is not provided, information can be transmitted and received between the valve controllers 17 via the wiring N, and based on such information, each valve controller 17 controls the corresponding driving unit 16 can be controlled. Therefore, the above-described valve structure 10 can be newly introduced simply and at low cost to a machine in which the integrated controller 18 (see FIG. 7) is not provided. Even when a plurality of valve controllers 17 are interconnected as shown in FIG. 8, an integrated controller 18 as shown in FIG. 7 may be provided.

[Modification]
For example, as shown in FIG. 9, the valve controller 17 may be provided at a position shifted from the reference axis Ax and the drive section 16 (particularly the movable section 25) with respect to the radial direction Dr. In this case also, the movable portion 25 of the driving portion 16 moves along the reference axis Ax according to the driving current, and the valve controller 17 is supported by the driving portion 16 . That is, in the valve structure 10 shown in FIG. 9, the valve controller 17 is supported by the driving section 16 via the valve housing 20, and the driving section 16 and the valve controller 17 are physically integrated. This can prevent the valve structure 10 from increasing in size in the axial direction Dx.

4A to 5C show the valve portion 15 constituted by an electromagnetic proportional valve for supplying pressure oil at a desired pressure to the hydraulic actuator A, but the valve portion 15 is a valve having other functions. may be configured by For example, the valve portion 15 may be configured by a directional switching valve capable of switching the flow direction of the pressure oil in the oil passage according to the drive current supplied to the drive portion 16 . For example, by controlling the amount of protrusion of the push rod 30 (movable part 25) according to the drive current, the position of the spool body can be adjusted to switch the flow direction of the pressure oil. A valve portion 15 may be configured. Since the typical structure of such a directional control valve is known, its illustration is omitted.

The invention is not limited to the embodiments and variants described above. For example, various modifications may be added to each element of the above-described embodiments and modifications, and the embodiments and modifications may be partially combined. Further, the effects achieved by the present invention are not limited to those described above, and specific effects according to specific configurations are exhibited.

10 valve structure 15 valve section 16 drive section 17 valve controller 18 integrated controller 20 valve housing 21 base section 25 movable section 26 drive housing 27 electromagnet 28 plunger 29 spring 30 push rod 31 plunger stopper 32 spring stopper 33 end position stopper 51 processing Unit 52 Storage unit 53 Input unit 54 Drive current supply unit 55 Output unit 56 Information output unit 57 Abnormality output unit 71 Power source 72 Other controller 73 Sensor 74 Display device 75 Alarm device A Hydraulic actuator Ax Reference axis Dr Radial direction Dx Axial direction Dx1 Forward axis direction Dx2 Reverse axis direction N Wiring P Hydraulic pressure source Ss Closed space T Drainage part

Claims (8)

a valve;
a drive unit that drives the valve unit according to a drive current;
a valve controller that is supported by the drive unit and controls the drive current supplied to the drive unit;
The valve controller is arranged in an enclosed space ,
the drive section includes a single movable section that moves on a reference axis in response to the drive current;
The valve structure according to claim 1, wherein the valve controller is provided at a position shifted from the drive section in a direction parallel to the reference axis . 2. The valve structure according to claim 1, wherein said closed space is provided in a liquid-tight manner. 3. The valve structure according to claim 1 , wherein the drive section includes an electromagnet through which the drive current flows, and a plunger that moves according to the magnetic force produced by the electromagnet. The valve structure according to any one of claims 1 to 3 , wherein the valve portion includes a spool driven by the driving portion. The valve structure according to any one of claims 1 to 4 , wherein the valve controller supplies the driving current to the driving section according to a driving signal input from another controller. The valve structure according to any one of claims 1 to 5 , wherein the valve controller supplies the driving current to the driving section according to a detection signal input from a sensor. The valve structure according to any one of claims 1 to 6 , wherein the valve controller is accommodated within the valve housing within a radial width of the valve housing that accommodates the driving portion. A construction machine comprising the valve structure according to any one of claims 1 to 7 .

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