CN111594506A - Solenoid proportional valve - Google Patents

Abstract

The invention provides an electromagnetic proportional valve. An electromagnetic proportional valve according to an embodiment of the present invention includes a pressure-receiving chamber maintained as a control pressure to be supplied to a controlled object, and a pressure sensor for detecting the control pressure in the pressure-receiving chamber.

Description

Solenoid proportional valve

technical field

The present disclosure mainly relates to an electromagnetic proportional valve.

Background technique

There is known an electromagnetic proportional valve that adjusts supply and discharge of pilot oil supplied to a hydraulic device to be controlled in accordance with an excitation current. A conventional electromagnetic proportional valve includes a valve body that accommodates a spool valve body that can move in the axial direction, and a drive device that drives the spool valve body. In this electromagnetic proportional valve, by switching the position of the spool in the axial direction, a control pressure corresponding to the position of the spool can be supplied to the hydraulic equipment to be controlled.

As disclosed in Japanese Patent Laid-Open No. 2005-188707 (Patent Document 1), an electromagnetic proportional valve is used as a pilot valve in a directional valve. In the reversing valve described in this publication, the spool position of the main spool is switched by the control pressure supplied from the electromagnetic proportional valve.

In order to calibrate the control pressure output from the solenoid proportional valve, the control pressure needs to be monitored. Conventionally, as described in Japanese Patent Laid-Open No. 2001-289202 (Patent Document 2), a connection module between an electromagnetic proportional valve and a valve structure to be controlled is provided with a connection module for acquiring an output from the electromagnetic proportional valve. A pressure measurement port for the control pressure, a pressure sensor for measuring the control pressure is attached to the pressure measurement port, and the control pressure is detected.

prior art literature

Patent Literature

Patent Document 1: Japanese Patent Laid-Open No. 2005-188707

Patent Document 2: Japanese Patent Laid-Open No. 2001-289202

SUMMARY OF THE INVENTION

Invention to solve problem

As described above, in order to detect the control pressure output from the conventional electromagnetic proportional valve, it is necessary to provide a pressure measuring port in the connection module and to provide a joint for attaching a pressure sensor to the connection module.

One of the objects of the present disclosure is to simplify the mechanism for detecting the control pressure of the electromagnetic proportional valve. One of the objectives of the present disclosure is to detect the control pressure of the electromagnetic proportional valve without arranging pressure measuring ports and joints outside the electromagnetic proportional valve. The objects of the present disclosure other than those described above will be apparent from the entire description of this specification.

solution to the problem

An electromagnetic proportional valve according to one aspect of the present invention includes a valve unit having a spool spool that can move in an axial direction and a control port that is disposed on one side of the spool spool in the axial direction and supplies a control pressure to a controlled object a part; and a drive device including: a solenoid coil disposed on the other side of the spool in the axial direction, and changing the control pressure by an excitation current; and a pressure-receiving chamber that accommodates the A solenoid coil is connected to the control port portion.

An electromagnetic proportional valve according to an aspect of the present invention includes a pressure sensor for detecting the control pressure in the pressure-receiving chamber.

An electromagnetic proportional valve according to an aspect of the present invention includes a valve unit including a valve body, a control port portion arranged on one side in the axial direction of the valve body, and a control port portion that is movably accommodated in the valve body and utilizes the valve body. a spool valve whose axial position changes the control pressure of the control port portion; and a drive device including a solenoid coil arranged on a side opposite to the control port portion with respect to the valve unit a side, the axial position of the spool is changed by an excitation current; a casing for accommodating the solenoid coil; and a pressure-receiving chamber located in the casing and connected to the control port part .

In a technical solution of the present invention, the housing includes a pressure sensor for detecting the control pressure in the pressure-receiving chamber.

The electromagnetic proportional valve according to one aspect of the present invention includes a cover part, the cover part covering the pressure sensor and mounted on the housing.

In a technical solution of the present invention, the driving device includes a driving rod, and the driving rod defines at least a part of the pressure chamber.

In a technical solution of the present invention, the driving device includes a plunger, which defines at least a part of the pressure-receiving chamber and is provided on the driving rod.

An electromagnetic proportional valve according to an aspect of the present invention includes a valve unit including a valve body, a control port portion arranged on one side in the axial direction of the valve body, and a control port portion that is movably accommodated in the valve body and utilizes the valve body. A spool valve whose axial position changes the control pressure of the control port portion; and a drive device including a solenoid coil arranged on the opposite side of the control port portion with respect to the valve unit , using the excitation current to change the axial position of the spool; a casing, which is used to accommodate the solenoid coil; and a pressure chamber, which is located in the casing and is connected to the control port; a pressure sensor for detecting the control pressure in the pressure-receiving chamber; and a cover for covering the pressure sensor and attached to the housing.

A reversing valve according to a technical solution of the present invention includes any one of the above-mentioned electromagnetic proportional valves.

A construction machine according to an aspect of the present invention includes the above-mentioned reversing valve.

effect of invention

By adopting the technical scheme of the present invention, the control pressure output from the electromagnetic proportional valve can be detected without arranging pressure measuring ports and joints outside the electromagnetic proportional valve.

Description of drawings

FIG. 1 is a diagram schematically showing the appearance of an electromagnetic proportional valve according to an embodiment of the present invention.

FIG. 2 is a longitudinal cross-sectional view of the electromagnetic proportional valve of FIG. 1 . In Figure 2, the spool is in the neutral position.

FIG. 3 is a longitudinal cross-sectional view of the electromagnetic proportional valve of FIG. 1 . In Figure 3, the spool is in the supply position.

FIG. 4 is a longitudinal cross-sectional view of the electromagnetic proportional valve of FIG. 1 . In Figure 4, the spool is in the discharge position.

FIG. 5 is a block diagram illustrating a selector valve including the electromagnetic proportional valve of FIG. 1 .

FIG. 6 is a block diagram illustrating a construction machine including the reversing valve of FIG. 5 .

Description of reference numerals

1. Electromagnetic proportional valve; 10. Driving device; 11. Housing; 12. Cover; 14a, 1st solenoid chamber; 14b, 2nd solenoid chamber; 15, pressure sensor; 23, solenoid coil; 24, fixed iron core; 26, plunger; 27, drive rod; 30, valve unit; 40, valve body; 70, slide valve core; P, pressure source; T, tank; ap, control port part; pp, pressure source port; tp, tank port; mp, main flow; cp1, first connection flow; cp2, second connection flow; cp3, third connection flow.

Detailed ways

Hereinafter, various embodiments of the present invention will be described with reference to the drawings as appropriate. In addition, the same code|symbol is attached|subjected to the same code|symbol in the several drawing about the common component in several drawings. It should be noted that, for ease of illustration, the figures are not necessarily drawn to exact scale. In each drawing, for convenience of description, some of the constituent elements are omitted in some cases.

1-4, the electromagnetic proportional valve 1 which concerns on one Embodiment of this invention is demonstrated. FIG. 1 is a diagram schematically showing an appearance of an electromagnetic proportional valve 1 according to an embodiment of the present invention, and FIGS. 2 to 4 are longitudinal cross-sectional views of the electromagnetic proportional valve 1 .

As shown in the figure, the electromagnetic proportional valve 1 includes a drive device 10 and a valve unit 30 . The drive device 10 and the valve unit 30 are arranged along the central axis A. In this specification, the direction along the central axis A may be simply referred to as the "axial direction". When referring to the front and rear in the axial direction in this specification, unless otherwise specified in the text, the front and rear directions shown in FIGS. 1 to 4 are used as a reference. Following this usage, the valve unit 30 is arranged in front of the drive device 10 .

The valve unit 30 includes a hollow valve body 40 extending in the axial direction, and a spool 70 provided in the valve body 40 so as to be movable in the axial direction.

The drive device 10 drives the spool 70 to control the axial position of the spool 70 . The drive device 10 includes a hollow housing 11 , a cover 12 , a pressure sensor 15 , a solenoid coil 23 , a fixed iron core 24 , a plunger 26 , and a drive rod 27 provided on the plunger 26 .

The casing 11 has a cylindrical shape extending in the direction of the central axis A. The housing 11 has an outer wall 11a and a guide wall 11b that define an inner space and an outer space thereof. The outer wall 11a has a cylindrical shape. The guide wall 11b has a cylindrical shape coaxial with the outer wall 11a and having a diameter smaller than that of the outer wall 11a. The guide wall 11b is provided at a position away from the outer wall 11a in the radial direction. Thereby, a space is defined between the outer wall 11a and the guide wall 11b. The solenoid coil 23 is supported in the space between the outer wall 11a and the guide wall 11b.

The housing 11 has a through hole extending in the axial direction. In other words, the casing 11 is hollow, and the inner space thereof is opened at the front and rear of the casing 11 . The front opening of the case 11 is sealed by the fixed iron core 24 . The rear opening of the casing 11 is sealed by the cover portion 12 . The cover portion 12 seals the rear opening of the casing 11 to maintain the pressure-receiving chamber at the control pressure. The lid portion 12 is a lid, a lid body, a seal, and a member other than the above-described members for closing the rear opening of the casing 11 and maintaining the pressure-receiving chamber at a control pressure. The cover portion 12 may be integrated with the housing 11 . In other words, the cover portion 12 and the housing 11 may also have an integral monolithic structure. In order to seal the opening of the case 11 , in addition to the fixed iron core 24 and the lid portion 12 , a sealing member is used as necessary. The shape and arrangement of the cover portion 12 are not limited to those explicitly described in this specification. The cover portion 12 may also cooperate with another member to seal the rear opening of the housing 11 .

Both the plunger 26 and the drive rod 27 are arranged on the central axis A in the cylindrical space defined by the guide wall 11b. Both the plunger 26 and the drive rod 27 are provided so as to be movable in the front-rear direction along the central axis A. As shown in FIG. The plunger 26 and drive rod 27 may also be of one-piece, one-piece construction. The drive rod 27 extends axially forward from the plunger 26 . In the case of the illustrated embodiment, the drive rod 27 protrudes slightly rearward in the axial direction from the plunger 26 . The drive rod 27 is a rod-shaped member extending along the central axis A.

At least a part of the plunger 26 is formed of a magnetic body. At least a part of the plunger 26 is arranged radially inward of the solenoid coil 23 . The plunger 26 has a through hole 26a extending in the axial direction at a position offset radially outward from the center axis A. As shown in FIG.

The inner space of the housing 11 is divided by the plunger 26 . Specifically, the inner space of the housing 11 is divided into a first solenoid chamber 14 a located on the rear side of the plunger 26 in the axial direction and a second solenoid chamber 14 b located on the front side of the plunger 26 in the axial direction. . The first solenoid chamber 14a and the second solenoid chamber 14b are connected by the through hole 26a. In this way, the through hole 26a connects the first solenoid chamber 14a and the second solenoid chamber 14b. In this specification, the flow path of the hydraulic oil defined by the through hole 26a may be referred to as the first connection flow path cp1.

The pressure sensor 15 is a sensor that detects the pressure of the first solenoid chamber 14a. The pressure sensor 15 transmits a detection signal indicating the detected pressure to a controller (not shown). In one embodiment, the pressure sensor 15 is provided so that at least a part of the pressure sensor 15 is exposed to the first solenoid chamber 14a. In the illustrated embodiment, a part of the lower surface 15a of the pressure sensor 15 may be exposed to the first solenoid chamber 14a, or the entire lower surface 15a may be exposed to the first solenoid chamber 14a. The lower surface 15a of the pressure sensor 15 may have a stainless steel diaphragm, a silicon diaphragm, or a diaphragm other than these. The pressure sensor 15 may include a strain gauge that converts a change in resistance due to deformation of the diaphragm into an electrical signal. The pressure sensor applicable to the present invention is not limited to the pressure sensor explicitly described in this specification.

In the illustrated embodiment, the pressure sensor 15 is provided in the cover portion 12 . At least a part of the pressure sensor 15 is covered by the cover portion 12 . The installation site of the pressure sensor 15 is not limited to the position shown in the figure. The pressure sensor 15 may be provided at another position of the cover portion 12 . The pressure sensor 15 may be provided in components other than the cover portion 12 of the electromagnetic proportional valve 1 . The pressure sensor 15 may be provided in the casing. For example, the pressure sensor 15 may be attached to the inner peripheral surface of the casing 11 .

The solenoid coil 23 is excited based on a control signal input from a controller (not shown). The controller includes a processor for performing various arithmetic processes, a memory for storing various programs and various data, and a device interface. The device interface is connected to the solenoid coil 23, the pressure sensor 15, and other devices. The controller outputs a control signal (control pulse) to the solenoid coil 23 to drive the plunger 26 and the drive rod 27 , thereby switching the position of the spool 70 . The controller determines the control pressure to be output to the control port portion ap to be described later based on the detection signal from the pressure sensor 15 .

The fixed iron core 24 has a substantially cylindrical shape. The fixed iron core 24 has a through hole extending in the axial direction at its radial center. The drive rod 27 is inserted into this through hole. The drive rod 27 can enter the inner space of the valve unit 30 from the fixed iron core 24 . The distal end (front end) of the drive rod 27 is in contact with the proximal end (rear end) of the spool 70 .

The fixed iron core 24 has a through hole 24a extending in the axial direction at a position deviated from the center axis A to the radially outer side. The through hole 24a is provided at a position facing the through hole 26a. The second solenoid chamber 14b and the reserve chamber 41 described later are connected by the through hole 24a. The second solenoid chamber 14b and the reserve chamber 41 are connected by the through hole 24a. In this specification, the flow path demarcated by the through hole 24a may be referred to as the second connection flow path cp2.

The plunger 26 is driven by the solenoid coil 23 . That is, the plunger 26 is driven by the solenoid coil 23 so as to be movable in the axial direction. Specifically, when an excitation current is applied to the solenoid coil 23, the plunger 26 is attracted to the fixed iron core 24, and thereby the plunger 26 and the drive rod 27 move forward in the axial direction. When the drive rod 27 moves forward in the axial direction, the spool 70 is pushed forward in the axial direction by the drive rod 27 . In this way, the spool 70 is driven by the drive unit including the solenoid coil 23 , the fixed iron core 24 , the plunger 26 and the drive rod 27 .

Next, the valve unit 30 will be described. As described above, the valve unit 30 includes the valve body 40 and the spool 70 movably provided on the valve body 40 . The valve main body 40 has a through hole 40a extending in the axial direction. The through hole 40a extends from the front end to the rear end of the valve body 40 in the axial direction. The valve main body 40 has a concave portion 40b at the center in the radial direction of the rear end thereof. The reserve chamber 41 is defined by the upper surface of the valve body 40 defining the recessed portion 40 b , the front surface of the fixed iron core 24 , the drive rod 27 , and the spool 70 .

The valve main body 40 has a pressure source port portion pp connected to the pressure source P, a tank port portion tp connected to the tank T, and a control port portion ap for outputting a control pressure. The control port portion ap is arranged on one side (front) in the axial direction of the spool 70 or the valve body 40 . The solenoid coil 23 is provided on the other side (rearward) in the axial direction of the spool 70 . The control port part ap is formed by the area|region near the front-end|tip of the through-hole 40a. The control port portion ap is connected to a hydraulic device to be controlled via a flow path not shown. As a result, the control pressure is supplied to the hydraulic equipment to be controlled by the control port portion ap.

The spool 70 has a shaft shape extending in the axial direction. The spool 70 is provided in the through hole 40a so as to be movable in the axial direction. The rear end of the spool 70 is in contact with the top end of the drive rod 27 . The spool 70 has a through hole 70a extending along the central axis A. The through hole 70a extends from the front end 70b to the rear end 70c of the spool. The spool 70 has a plurality of flow paths through which the hydraulic oil flows. In the illustrated embodiment, the main passage mp through which the hydraulic oil flows is defined by the through hole 70a of the spool 70 . The main flow path mp extends from the front end 70b to the rear end 70c of the spool. Therefore, the main flow path mp is opened at the control port portion ap. In addition, the spool 70 has a first branch flow path bp1 and a second branch flow path bp2 extending from the main flow path mp to the outer surface of the spool 70 . The spool 70 has a third connection flow path cp3 that connects the main flow path mp and the reserve chamber 41 at the rear end in the axial direction.

The valve unit 30 has an urging member 80 arranged in the valve body 40 . The urging member 80 urges the spool 70 toward the drive rod 27 . In other words, the urging member 80 urges the spool 70 rearward along the central axis A. The urging member 80 is, for example, a compression spring.

The spool 70 is always in contact with the drive rod 27 by the urging force received from the urging member 80 toward the rear in the axial direction. Therefore, when the drive rod 27 moves forward along the center axis A, the spool 70 also moves forward along the center axis with respect to the valve body 40 by the thrust force from the drive rod 27 . Conversely, when the drive rod 27 moves rearward along the center axis A, the spool 70 moves backward along the center axis A while maintaining contact with the drive rod 70 by the urging force from the urging member 80 . . The thrust force acting on the spool 70 from the drive rod 27 has a magnitude corresponding to the excitation current of the solenoid coil 23 . Therefore, the axial position of the spool 70 can be controlled by adjusting the magnitude of the excitation current applied to the solenoid coil 23 .

The spool 70 is switched to at least any one of a neutral position, a supply position, and a discharge position. 2 shows the solenoid proportional valve 1 with the spool 70 at the neutral position, FIG. 3 shows the solenoid proportional valve 1 with the spool 70 at the supply position, and FIG. 4 shows the solenoid proportional valve 1 with the spool 70 at the discharge position.

When the spool 70 is in the neutral position shown in FIG. 2 , the ports pp, tp, and ap are blocked from each other. In this case, supply and discharge of hydraulic oil to the hydraulic equipment connected to the control port portion ap is not performed.

When the spool 70 is in the supply position shown in FIG. 3 , the control port ap is connected to the pressure source port pp via the main flow path mp and the first branch flow path bp1, and the tank port tp is connected to the other ports pp, blocked between APs. Thereby, the hydraulic oil is supplied from the pressure source P to the hydraulic equipment. In addition, the control port portion ap passes through the main flow path mp, the third connection flow path cp3, the preparatory chamber 41, the second connection flow path cp2, the second solenoid chamber 14b, and the first connection flow path cp1 and the first solenoid chamber. 14a is connected, so when the spool 70 is at the supply position, the first solenoid chamber 14a is maintained at the control pressure, which is the pressure of the hydraulic fluid in the control port portion ap. The first solenoid chamber 14a and the space between the first solenoid chamber 14a and the control port portion ap (for example, the second solenoid chamber 14b) are maintained at the control pressure of the control port portion ap. Some or all of them are set as pressurized chambers. For example, at least one of the first solenoid chamber 14a and the second solenoid chamber 14b is set as a pressure-receiving chamber maintained as the control pressure of the control port portion ap. The solenoid coil 23 is accommodated in the pressure-receiving chamber. At least a portion of the pressurized chamber is delimited by the drive rod 27 . At least a portion of the pressurized chamber is delimited by the plunger 26 .

When the spool 70 is at the discharge position shown in FIG. 4 , the control port portion ap is connected to the tank port portion tp via the main flow path mp and the first branch flow path bp1 , and the pressure source port portion pp is connected to the other ports tp and ap. blocked in between. Thereby, the oil is discharged to the tank T from the hydraulic equipment.

Next, the operation of the electromagnetic proportional valve 1 will be described. When the solenoid coil 23 is not excited, the spool 70 is maintained at the discharge position shown in FIG. 4 under the urging force of the urging member 80 . At this time, as described above, the flow path from the control port portion ap to the tank port portion tp via the main flow path mp and the second branch flow path bp2 of the spool 70 is opened. Therefore, oil is recovered from the hydraulic equipment connected to the control port portion ap to the tank T connected to the tank port portion tp.

From this state, when the solenoid coil 23 is excited, the plunger 26 is driven, and the plunger 26 moves forward in the axial direction against the urging force from the urging member 80 together with the drive rod 27 . At this time, since the front end of the drive rod 27 is in contact with the spool 70 , an axially forward thrust acts on the spool 70 . Under the action of this thrust, the spool 70 reaches the neutral position shown in FIG. 2 from the discharge position. When the spool 70 is in the neutral position, the connection between the second branch flow path bp2 and the tank port portion tp is also blocked while the connection between the first branch flow path bp1 and the pressure source port portion pp is kept blocked. . Therefore, when the spool 70 is in the neutral position, the discharge of oil from the hydraulic device connected to the control port portion ap and the supply of oil to the hydraulic device are not performed.

When a larger excitation current is applied to the solenoid coil 23, the plunger 26 and the drive rod 27 move further forward in the axial direction. The spool 70 reaches the supply position shown in FIG. 3 by the thrust force received from the drive rod 27 . When the spool 70 is at the supply position, the flow path from the control port portion ap to the pressure source port portion pp via the main flow mp and the first branch flow path bp1 of the spool 70 is opened. Thereby, oil is supplied from the pressure source P connected to the pressure source port portion pp to the hydraulic equipment connected to the control port portion ap. When the spool 70 is at the supply position, the supply amount of oil from the pressure source P to the hydraulic equipment is based on the area where the first branch flow path bp1 and the pressure source port portion pp overlap, that is, the first branch flow path bp1 and the pressure The amount of overlap of the source port portion pp varies. More specifically, as the excitation current increases, the amount of overlap between the first branch flow path bp1 and the pressure source port portion pp increases, and more oil flows from the pressure source port portion pp to the control port portion ap. Therefore, the larger the excitation current, the larger the control voltage output to the control port portion ap.

As described above, the control port portion ap passes through the main flow path mp, the third connection flow path cp3, the preparatory chamber 41, the second connection flow path cp2, the second solenoid chamber 14b, and the first connection flow path cp1 and the first solenoid The tube chamber 14a is connected. Therefore, while the spool 70 is at the supply position, the first solenoid chamber 14a is maintained at the control pressure output from the control port portion ap. The pressure of the first solenoid chamber 14 a is detected by the pressure sensor 15 , and an electric signal indicating the detected pressure is output from the pressure sensor 15 to the controller. As described above, the control pressure output from the electromagnetic proportional valve 1 can be detected without installing a pressure measuring port or an external pressure sensor between the electromagnetic proportional valve 1 and the hydraulic equipment to be controlled.

Next, an application example of the electromagnetic proportional valve 1 will be described with reference to FIGS. 5 and 6 . FIG. 5 is a block diagram illustrating the selector valve 100 including the electromagnetic proportional valve 1 . As shown in the figure, the selector valve 100 includes an electromagnetic proportional valve 1 and a valve structure 2 that operates by a control pressure supplied from the electromagnetic proportional valve 1 . The valve structure 2 includes a main spool, and the position of the main spool is switched by the control pressure output from the electromagnetic proportional valve 1 to adjust the supply amount of hydraulic oil to a hydraulic cylinder (not shown).

FIG. 6 is a block diagram illustrating the construction machine 200 including the reversing valve 100 . The construction machine 200 includes the diverter valve 100 . The construction machine is, for example, a hydraulic excavator that works with hydraulic pressure. Construction machine 200 includes various hydraulic cylinders. The hydraulic cylinders included in the construction machine 200 include a boom cylinder that drives a boom, an arm cylinder that drives an arm, a bucket cylinder that drives a bucket, and other hydraulic cylinders. The selector valve 100 controls the supply amount of hydraulic oil to the hydraulic cylinder included in the construction machine 200 .

Next, the effects obtained by the above-described embodiment will be described. The above-described electromagnetic proportional valve 1 includes a pressure-receiving chamber maintained as a control pressure to be supplied to a controlled object, and a pressure sensor 15 for detecting the control pressure in the pressure-receiving chamber. Accordingly, it is not necessary to provide a pressure measuring port for acquiring the control pressure and a joint for attaching a pressure sensor to the outside of the electromagnetic proportional valve 1 . Therefore, according to the electromagnetic proportional valve 1 of the above-described embodiment, the control pressure output from the electromagnetic proportional valve 1 can be detected by a simple mechanism. Furthermore, since the pressure measuring port and the fitting for the pressure sensor are not required, the connection module between the electromagnetic proportional valve 1 and the hydraulic equipment to be controlled can be made compact.

In the above-described embodiment, the pressure-receiving chamber is, for example, at least one of the first solenoid chamber 14a and the second solenoid chamber 14b. In the illustrated embodiment, the pressure sensor 15 detects the pressure of the first solenoid chamber 14a. The pressure sensor 15 may be provided to detect the pressure of the second solenoid chamber 14b. In this case, the pressure sensor 15 may be provided so as to be exposed to the second solenoid chamber 14b. Two pressure sensors 15 may be provided to detect the control pressure in each of the first solenoid chamber 14a and the second solenoid chamber 14b.

In the above-described embodiment, the pressure sensor 15 is provided in the casing 11 . Therefore, it is not necessary to provide a pressure sensor outside the electromagnetic proportional valve 1 . Therefore, the control pressure of the electromagnetic proportional valve can be detected with a compact mechanism.

In the above-described embodiment, the pressure sensor 15 is provided in the lid portion 12 for sealing the opening of the case 11 . By providing the pressure sensor 15 on the cover for sealing the opening, the pressure sensor 15 is provided at a position close to the surface of the housing 11 . Thereby, the detection signal of the pressure sensor 15 can be easily taken out to the outside. For example, a signal line is provided between the pressure sensor 15 and the controller, and the detection signal of the pressure sensor 15 is transmitted to the controller via the signal line. In this case, the routing of the signal line is easy.

The dimensions, materials, and arrangements of the constituent elements described in this specification are not limited to those explicitly described in the embodiments, and the constituent elements can be modified to have arbitrary dimensions that can be included in the scope of the present invention , material and configuration. In addition, components that are not explicitly described in this specification may be added to the described embodiments, and some of the components described in the respective embodiments may be omitted.

The specific shapes, arrangements, functions, and materials of the constituent members of the drive device 10 and the valve unit 30 clearly shown in this specification and the drawings are examples. The shapes, arrangements, functions, and materials of the respective constituent members of the drive device 10 and the valve unit 30 can be appropriately changed within the scope of not deviating from the gist of the present invention. For example, the drive device 10 may drive the drive rod so that the drive rod 27 moves axially rearward when the excitation current is made to flow to the solenoid coil 23 .

Claims (10)

1. An electromagnetic proportional valve, comprising: a valve unit having a spool spool that can move in an axial direction, and a control port portion that is arranged on one side of the spool spool in the axial direction and supplies a control pressure to a control object; and A drive device includes: a solenoid coil arranged on the other side of the spool in the axial direction, and changing the control pressure by an excitation current; and a pressure receiving chamber that accommodates the solenoid A coil is connected to the control port part. 2. The solenoid proportional valve according to claim 1, wherein, The solenoid proportional valve includes a pressure sensor for detecting the control pressure in the pressure-receiving chamber. 3. An electromagnetic proportional valve, comprising: A valve unit including a valve body, a control port portion disposed on one side in the axial direction of the valve body, and a control port portion movably accommodated in the valve body and using the axial position to control a control pressure of the control port portion Changed spool; and A drive device including a solenoid coil arranged on a side opposite to the control port portion with respect to the valve unit, and changing the position of the spool in the axial direction by an excitation current ; a housing for accommodating the solenoid coil; and a pressure-receiving chamber located in the housing and connected to the control port portion. 4. The solenoid proportional valve according to claim 3, wherein, The housing includes a pressure sensor for detecting the control pressure in the pressurized chamber. 5. The solenoid proportional valve of claim 4, wherein: The electromagnetic proportional valve includes a cover that covers the pressure sensor and is mounted on the housing. 6. The electromagnetic proportional valve according to any one of claims 3 to 5, wherein: The drive means includes a drive rod that delimits at least a portion of the pressurized chamber. 7. The electromagnetic proportional valve according to any one of claims 3 to 6, wherein: The driving device includes a plunger, which defines at least a part of the pressure-receiving chamber, and is provided on the driving rod. 8. An electromagnetic proportional valve, comprising: A valve unit including a valve body, a control port portion disposed on one side in the axial direction of the valve body, and a control port portion movably accommodated in the valve body and using the axial position to control a control pressure of the control port portion Changed spool; A driving device including a solenoid coil arranged on the opposite side of the valve unit from the control port portion, and changing the position of the spool in the axial direction by an excitation current ; a housing for accommodating the solenoid coil; and a pressurized chamber located within the housing and connected to the control port portion; a pressure sensor for detecting the control pressure in the pressurized chamber; and A cover portion covering the pressure sensor is attached to the housing. 9 . A reversing valve comprising the electromagnetic proportional valve according to claim 1 . 10 . 10. A construction machine comprising the reversing valve of claim 9.

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