JP2020094632A - Flow rate control valve - Google Patents

Abstract

To provide a flow rate control valve which can control an unintentional abrupt opening adjustment at a manual operation.SOLUTION: This flow rate control valve 100 comprises a main valve 1 and a pilot valve 2. The pilot valve 2 includes a valve body 50, a solenoid 60 and a manual operation part 70. The manual operation part 70 includes a grip part 71, an elastic member 72 for generating a drive force according to a moving amount St of the grip part 71 in a stroke direction, and a guide part 80 for guiding the grip part 71 to a position passing a first position Q1, and passing over the first position Q1 from an initial position Q0. The guide part 80 is constituted so that a moving amount St in the stroke direction becomes small with respect to the moving amount Mv of the grip part 71 along the guide part 80 in at least either of a region between the initial position Q0 and the first position Q1, and a region passing over the first position Q1.SELECTED DRAWING: Figure 2

Description

The present invention relates to a flow control valve, and more particularly to a flow control valve that can be manually operated without using a driving force of a solenoid.

Conventionally, there is known a flow control valve that can be manually operated without using a driving force of a solenoid (see, for example, Patent Document 1).

In the above Patent Document 1, a spool is slidably provided in a sliding hole formed in a body, a nozzle is projected from one end of the spool, and a flapper is attached to a tip of a rod of a movable iron core of a proportional solenoid. Disclosed is a flow rate control valve that is opposed to a nozzle and supplies pilot oil to the nozzle. When the proportional solenoid is energized, the flapper position is determined according to the magnitude of the input current, and the flow rate is adjusted accordingly. The flow rate adjusting valve is slidably provided with an adjusting rod that urges a rod of the movable iron core opposite to the flapper via a spring. When you want to change the flow rate manually, when you push the adjustment rod, the spring is compressed and the biasing force increases, the flapper moves via the movable iron core, the spool moves following it, and the opening degree changes. It is expanded to increase the oil flow rate.

Japanese Utility Model Publication No. 63-27122

However, in the flow rate adjusting valve of Patent Document 1 described above, when the adjusting rod is pushed during the manual operation, the urging force corresponding to the compression amount of the spring acts to move the flapper, so that the adjusting rod is moved. The opening will increase as it is. Therefore, it is impossible to perform fine control as in the case of adjusting the opening by controlling the input current of the solenoid. For example, if the user erroneously presses the adjusting rod during manual operation, the adjusting rod may be unintentionally pushed to the limit, and the valve opening may suddenly change to the maximum opening.

The manual operation function is a reserve for control by the solenoid, and is assumed to be used in an emergency, for example, when the power source is lost and the solenoid does not function, and the valve opening is manually adjusted. In this case, since the frequency of use of the manual operation is not high, the user is not always familiar with the manual operation. Therefore, it is desired that even a user who is not familiar with the manual operation is prevented from performing an unintended operation such as suddenly changing the valve opening.

The present invention has been made to solve the above problems, and an object of the present invention is to prevent unintended sudden opening adjustment during manual operation. It is to provide a flow control valve.

In order to achieve the above object, a flow control valve according to the present invention includes a main valve and a pilot valve, and the pilot valve is a valve that moves in a stroke direction and changes a valve opening degree of a pilot path to the main valve. Body, a solenoid that applies a driving force in the stroke direction to the valve element, and a manual operation unit that applies a driving force in the stroke direction to the valve element or a movable piece of the solenoid by a manual operation. And an elastic member that generates a driving force according to the amount of movement of the grip portion in the stroke direction, and a guide portion that guides the grip portion from the initial position to a position that passes through the first position and beyond the first position. The portion is configured such that the movement amount in the stroke direction is smaller than the movement amount along the guide portion of the grip portion between at least one of the initial position and the first position and at a region beyond the first position. Has been done.

In the flow rate control valve according to the present invention, with the above configuration, when the grip portion is moved by the manual operation, at least one of the area between the initial position and the first position of the grip portion and the area beyond the first position, The movement amount in the stroke direction is smaller than the movement amount along the guide portion. That is, the movement of the gripper is an area in which the amount of movement in the stroke direction that contributes to the change in the valve opening is smaller than the distance (actual operation amount) that the user actually moved the gripper along the guide. It is provided on the route. Therefore, even if the user unintentionally moves the grip portion by a large amount, the valve opening of the pilot path can be changed smaller than the actual operation amount. The opening can be controlled finely. As a result, it is possible to prevent unintended sudden opening adjustment during manual operation. Also, in the area where the amount of movement in the stroke direction is smaller than the amount of movement along the guide part, it is possible to make fine adjustments to the opening while performing manual operation. It is possible to perform precise opening degree adjustment (flow rate control) close to the above control.

In the flow rate control valve according to the above invention, preferably, the guide portion guides the gripping portion from the initial position in the stroke direction to the first position and the first guide portion to the second position at the end in the stroke direction. And a second guide portion, and at least one of the first guide portion and the second guide portion is configured to guide the grip portion in a direction inclined with respect to the stroke direction. According to this structure, with at least one of the first guide portion and the second guide portion, the guide portion of the grip portion can be guided with a simple configuration in which the grip portion is guided in a direction inclined with respect to the stroke direction. The amount of movement in the stroke direction can be made smaller than the amount of movement along the stroke. Further, the larger the inclination angle of the guide direction with respect to the stroke direction, the smaller the movement amount in the stroke direction can be made, so that the relationship between the movement amount in the stroke direction and the actual operation amount can be easily set. ..

In this case, preferably, the grip portion is movable in the stroke direction and the rotation direction around the stroke direction, the first guide portion is formed to extend along the stroke direction, and the second guide portion is formed in the stroke direction. It is formed so as to extend in a direction inclined with respect to the rotation direction. According to this structure, in the second guide portion, the user performs an operation of moving the grip portion in the stroke direction while twisting the grip portion in the rotation direction. According to the combined operation of the twisting operation and the pushing operation, it is possible to effectively prevent the operation amount from being erroneous as compared with the operation of simply pushing the grip portion. Further, considering the operation control of the hydraulic machine by the flow control valve, for example, the second guide portion (the first guide portion) having a larger valve opening degree than the first guide portion (from the initial position to the first position) having a small valve opening degree. In the control from the 1st position to the 2nd position at the end), since delicate control is required, it is possible to reduce the movement amount in the stroke direction with respect to the actual operation amount in the second guide portion where the valve opening becomes large. The configuration is useful.

In the configuration in which the guide portion includes the first guide portion and the second guide portion, it is preferable that the guide portion stays at the initial position in the stroke direction from the first restricting position that restricts the movement of the gripping portion in the stroke direction. It further includes a third guide portion that guides the movement of the grip portion to the first movable position that allows the movement in the stroke direction. According to this structure, in the initial position in the stroke direction, the opening degree adjustment by the manual operation is prohibited at the first regulation position, and the grip portion is operated from the first regulation position to the first movable position, so that the manual operation is not performed for the first time. The opening degree can be adjusted. Therefore, it is possible to prevent the user from mistakenly moving the gripper to perform a manual operation without providing a cover or a complicated safety mechanism for preventing the gripper from touching.

In the configuration in which the guide portion includes the first guide portion and the second guide portion, preferably, the manual operation portion includes a biasing member that biases the grip portion in a direction from the first movable position to the first restricted position. Further includes. According to this structure, unless the user intentionally moves the gripping portion to the first movable position against the urging force of the urging member, the opening degree is not manually adjusted. As a result, it is possible to more reliably suppress the erroneous operation of the user.

In the configuration in which the guide portion includes the first guide portion and the second guide portion, it is preferable that the guide portion is in the second position in the stroke direction and the second movable position that allows the grip portion to move in the stroke direction. Further includes a fourth guide portion that guides the movement of the gripping portion to the second regulation position that regulates the movement in the stroke direction. According to this structure, when the grip portion is moved to the second position and the valve opening is maximized, the grip portion is moved to the second regulation position so that the second position (maximum opening) is maintained. It is possible to fix and avoid returning to the first position side. Therefore, when it is desired to keep the maximum opening during manual operation, the user does not have to continue operating the grip portion, so that the convenience of the flow control valve during manual operation can be improved.

In the above invention, preferably, the main valve includes a neutral position, a standby position that is a starting point of opening control, and a control region in which the opening changes according to the spool movement amount, according to the pressure from the pilot path. The pilot valve moves the valve element to a valve opening degree at which the spool of the main valve moves to the standby position when the grip moves to the first position, and the pilot valve moves the grip to the first position. Is configured to move the valve element to a valve opening degree at which the spool of the main valve moves to the control area. According to this structure, the main valve has a structure in which the flow rate is not controlled between the neutral position and the standby position, so that the leakage of the hydraulic oil between the neutral position and the control region is effective. Can be suppressed. Then, during the manual operation, the user moves the grip portion to the first position to set the spool to the standby position, and the flow rate control can be started from a region beyond the first position. When operating the grip part, the opening degree change of the valve body with respect to the actual operation amount of the grip part depending on whether the grip part is moved from the initial position to the first position or when the grip part is moved beyond the first position. The speed (movement amount in the stroke direction) can be changed. Accordingly, even during manual operation, the user can easily grasp and operate up to which position in the movable range of the grip portion is the standby position and from which position is the control region.

According to the present invention, as described above, it is possible to provide a flow rate control valve capable of suppressing unintended sudden opening adjustment during manual operation.

It is a figure showing an example of a hydraulic circuit to which a flow control valve is applied. It is sectional drawing which showed the structural example of the flow control valve. It is the figure which showed the state which the spool moved to the standby position by the side of the 1st port. It is a figure showing the state where the spool moved to the control area on the side of the first port. It is the figure which showed the state which the spool moved to the standby position by the side of the 2nd port. It is a figure showing the state where the spool moved to the control area on the side of the second port. 6 is a graph showing an example of opening/closing operation of a flow control valve. It is sectional drawing which showed the structural example of the manual operation part of a pilot valve. It is sectional drawing which showed the manual operation part in the state which the holding part moved to the 2nd position. It is a side view of the manual operation part shown in FIG. It is a schematic diagram for demonstrating the structure of a guide part. It is a schematic diagram for demonstrating the rotation angle range of a holding part. It is sectional drawing which showed the modification of the main valve. It is a figure showing the 1st modification of a guide part. It is the figure which showed the 2nd modification of a guide part. It is the figure which showed the 3rd modification of a guide part.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

First, a flow control valve according to an embodiment will be described with reference to FIGS. 1 to 12.

As shown in FIG. 1, the flow control valve 100 according to the present embodiment is a hydraulic valve that controls the supply of hydraulic oil to a hydraulic machine such as a hydraulic actuator. The flow control valve 100 includes a main valve 1 and a pilot valve 2. The main valve 1 controls the flow rate of hydraulic oil supplied to the hydraulic machine connected to the flow rate control valve 100. The pilot valve 2 is connected to the main valve 1 and controls the valve opening of the main valve 1 by controlling the pressure (pilot hydraulic pressure) of the hydraulic oil supplied to the main valve 1.

[Overall configuration example of hydraulic circuit]
In the following, as an example, an example will be described in which the flow rate control valve 100 is connected to a lifting hydraulic cylinder (lift cylinder) of a forklift, and the flow rate control valve 100 is used to control the supply of hydraulic oil for moving the cylinder up and down.

As shown in FIG. 1, the flow rate control valve 100 is connected to a hydraulic cylinder 101, a hydraulic pump 102, and an oil tank 103 via a hydraulic fluid flow path. Specifically, the main valve 1 is provided with four oil passages of a first port A, a second port B, a supply port P and a discharge port T. The pilot valve 2 includes four oil passages, a first port PA, a second port PB, a supply port PP, and a discharge port PT.

The hydraulic cylinder 101 has a structure in which a piston 111 and a rod 112 connected to the piston 111 are slidably provided in a tube 113. The hydraulic cylinder 101 is, for example, a single rod cylinder, and a rod 112 projects outside from one end side of the tube 113. The inside of the tube 113 is partitioned by the piston 111 into a rod side oil chamber 114 and a head side oil chamber 115.

The first port A of the main valve 1 is connected to the head side oil chamber 115 via the check valve 104. The second port B of the main valve 1 is connected to the rod side oil chamber 114. The first port A may be connected to the rod side oil chamber 114 and the second port B may be connected to the head side oil chamber 115. The check valve 104 allows the working oil to flow from the first port A toward the head side oil chamber 115, and prevents the working oil from flowing from the head side oil chamber 115 toward the first port A. .. The check valve 104 is a pilot check valve, and the pilot port is connected to the flow path between the rod side oil chamber 114 and the second port B.

The supply port P of the main valve 1 and the supply port PP of the pilot valve 2 are connected to the discharge side of the hydraulic pump 102. The hydraulic pump 102 is driven by a motor 121 and supplies the hydraulic oil in the oil tank 103 to the main valve 1 and the pilot valve 2 at a predetermined pressure. The discharge port T of the main valve 1 and the discharge port PT of the pilot valve 2 are connected to the oil tank 103.

Comparing the pressures of the hydraulic oil in the flow control valve 100, the pressure of the supply port P(PP) on which the discharge pressure of the hydraulic pump 102 acts is the highest, and the pressure of the discharge port T(PT) released in the oil tank 103. Is the lowest. The pressures of the first port A, the second port B, the first port PA, and the second port PB are between the supply port P(PP) and the discharge port T(PT). The main valve 1 depressurizes the high-pressure hydraulic oil supplied from the supply port P and sends it out from the first port A or the second port B. The pilot valve 2 depressurizes the high-pressure hydraulic oil supplied from the supply port PP and sends it out from the first port PA or the second port PB.

The first port PA and the second port PB of the pilot valve 2 are connected to the main valve 1 via the pilot path 15, respectively. The main valve 1 performs flow path switching and flow rate control by the pilot oil pressure of the hydraulic oil supplied from the external pilot valve 2.

The main valve 1 connects the supply port P and the first port A with the neutral state in which both the first port A and the second port B are shut off from the supply port P, and the second port B and the discharge port T are connected. And a PB control state in which the supply port P and the second port B are connected and a first port A and the discharge port T are connected, which functions as a directional switching valve.

In the neutral state, all of the supply port P, the first port A and the second port B are shut off by the main valve 1. That is, the main valve 1 is configured to be fully closed in the neutral state. In the neutral state, the hydraulic oil in the hydraulic cylinder 101 does not flow, so the position of the rod 112 is held.

In the PA control state, the high-pressure hydraulic oil supplied from the hydraulic pump 102 passes through the supply port P and the first port A of the main valve 1 and flows into the head-side oil chamber 115 of the hydraulic cylinder 101, causing the rod 112 to flow. Push out. The hydraulic oil pushed out from the rod-side oil chamber 114 passes through the second port B and the discharge port T of the main valve 1 and is returned to the oil tank 103. The lifting hydraulic cylinder operates in the ascending direction (vertically upward direction).

In the PB control state, the high-pressure hydraulic oil supplied from the hydraulic pump 102 passes through the supply port P and the second port B of the main valve 1 and flows into the rod-side oil chamber 114 of the hydraulic cylinder 101, causing the rod 112 to flow through the rod 112. Pull in. The hydraulic oil pushed out from the head side oil chamber 115 passes through the first port A and the discharge port T of the main valve 1 and is returned to the oil tank 103. The lifting hydraulic cylinder operates in a descending direction (vertically downward direction).

Then, in the PA control state and the PB control state, the main valve 1 controls the discharge flow rate of the hydraulic oil from the port according to the position (stroke amount) of the spool 20 (see FIG. 2) moved by the pilot hydraulic pressure. To be done. The stroke amount of the spool 20 is determined by the magnitude of pilot hydraulic pressure supplied from the pilot valve 2. The pilot valve 2 changes the valve opening degree of the first port PA or the second port PB that supplies pilot hydraulic pressure to the main valve 1 by driving the solenoid 60 (see FIG. 2) by a signal from the controller 106. ..

Here, a backup pressure source 105 including an accumulator and the like is connected to a hydraulic oil supply path from the hydraulic pump 102 to the flow control valve 100. The backup pressure source 105 is configured to be able to supply pressure to the hydraulic circuit (hydraulic pump) even when the pressure supply from the hydraulic pump 102 is stopped, for example, when the power supply to the hydraulic circuit (hydraulic pump) is lost. When the power is lost, the solenoid 60 of the pilot valve 2 may not be able to be driven. The pilot valve 2 included in the flow control valve 100 of the present embodiment has a manual operation unit 70 (see FIG. 2) for a user to manually operate the opening control instead of the opening control of the main valve 1 by the solenoid 60. ) Is provided. The main valve 1 can be switched between the neutral state, the PA control state, and the PB control state by operating the manual operation unit 70.

It should be noted that the manual operation of the pilot valve 2 at the time of loss of power is an example of a typical usage pattern, and when power is supplied, the manual operation unit 70 replaces the opening control by the solenoid 60. Manual operation of the pilot valve 2 may be performed.

[Structure of flow control valve]
Next, an example of a specific structure of the flow rate control valve 100 will be described with reference to FIGS.

In the example of FIG. 2, the main valve 1 is configured as a spool type (slide spool type) proportional flow control valve. The proportional flow rate control valve is a control valve configured such that the flow rate of the output hydraulic oil is proportional to the position (stroke amount) of the spool. The pilot valve 2 is configured as a spool type (slide spool type) pressure control valve.

(Main valve)
First, the structure of the main valve 1 will be described. The main valve 1 includes a body 10 having an oil passage through which hydraulic oil flows in and out, and a spool 20 movably held in the body 10 to open and close the oil passage. FIG. 2 shows the spool 20 in the neutral position S0.

The body 10 has a spool chamber 11 in which the spool 20 is arranged, and a pair of pilot chambers 12 arranged on both sides of the spool chamber 11. A spool 20 is disposed in the spool chamber 11 so as to be slidable along the axial direction (X direction). The X direction in which the spool 20 slides is called the stroke direction.

The oil passages of the supply port P, the discharge port T, the first port A and the second port B penetrate the body 10 from the outer periphery of the body 10 and communicate with the spool chamber 11. In the stroke direction (X direction), the supply port P is arranged in the center of the spool chamber 11, and the first port A and the second port B are arranged on both sides of the supply port P, respectively. Discharge ports T are arranged outside the first port A and the second port B, respectively.

A valve seat portion 13 formed of the inner peripheral surface of the spool chamber 11 (body 10) is provided between the oil passages of the supply port P, the discharge port T, the first port A and the second port B. When the spool 20 is in the neutral position S0 (see FIG. 2) and the standby position S1 (see FIGS. 3 and 5) described later, the valve seat portion 13 is controlled by the outer peripheral surface (sliding surface) 21 of the opposing spool 20. Shut off the oil passage.

A pilot path 15 for connecting to the pilot valve 2 is provided in each of the pilot chambers 12 on both sides in the stroke direction. The pair of pilot chambers 12 are a pilot chamber 12a connected to the first port PA of the pilot valve 2 via the pilot path 15 and a pilot chamber 12a connected to the second port PB of the pilot valve 2 via the pilot path 15. 12b and. Due to the pilot hydraulic pressure input to the pilot chamber 12, an operating force that moves the spool 20 in the spool chamber 11 in the stroke direction (X direction) acts on the spool 20.

The spool 20 is a roughly cylindrical shaft member. The spool 20 is provided with an outer peripheral surface 21, which is a sliding surface, and a groove portion 22 for switching between the oil passages so that they communicate with each other. The groove portion 22 is formed over the entire circumference in the circumferential direction of the spool 20, and is arranged at the neutral position S0 corresponding to the positions of the supply port P and each discharge port T. The two outer peripheral surfaces 21 between the groove portions 22 are formed so as to close the first port A and the second port B at the neutral position S0. The outer peripheral surfaces 21 at both ends of the spool 20 are provided so as to close the space between the pilot chamber 12 and the spool chamber 11. The groove portion 22 is formed to make the flow rate of the hydraulic oil proportional to the stroke amount of the spool 20 when the first port A or the second port B is connected to the supply port P or the discharge port T.

A bypass passage 24 that connects the groove portions 22 on both sides in the axial direction (X direction) is formed inside the spool 20. The bypass passage 24 opens in the surface of the spool 20 (bottom of the groove 22) at a position in the X direction that corresponds to each discharge port T at the neutral position S0.

The spool 20 has a neutral position S0 according to the pilot oil pressure from the pilot path 15, a standby position S1 (see FIG. 3 and FIG. 5) which is a start point of the opening control, and an opening according to the spool movement amount. It is configured to move to the changing control area S2 (see FIGS. 4 and 6).

(Biasing means)
The main valve 1 is provided with a biasing means 30 for holding the spool 20 at the neutral position S0 by a biasing force. Due to the urging force of the urging means 30, the main valve 1 is maintained in the neutral state (fully closed state) when the pilot hydraulic pressure is not supplied. Further, the biasing means 30 associates the pilot hydraulic pressure supplied from the pilot valve 2 with the stroke amount of the spool 20 by the biasing force.

When the input pilot oil pressure exceeds a predetermined threshold value, the spool 20 reaches the standby position S1. When the pilot oil pressure further rises, the spool 20 reaches the control area S2 (see FIGS. 4 and 6). In the control region S2, the opening area (flow passage cross-sectional area) between each port and the groove portion 22 changes according to the stroke amount of the spool 20, so that the flow rate of the hydraulic oil is proportional to the stroke amount of the spool 20.

The main valve 1 is supplied with an operating force by pilot hydraulic pressure in a magnitude between a first threshold TH1 which is an upper limit for holding the spool 20 at the neutral position S0 and a second threshold TH2 which is larger than the first threshold TH1. Then, the spool 20 is configured to move from the neutral position S0 to the standby position S1 against the biasing force of the biasing means 30. Then, when an operating force larger than the second threshold value TH2 is supplied by the pilot oil pressure to the main valve 1, the spool 20 moves from the standby position S1 to the control area S2 against the biasing force of the biasing means 30. Is configured.

The standby position S1 is a position between the neutral position S0 and the control area S2, and is a position immediately before the control by the control area S2 is started. The standby position S1 is set on each of the first port A side and the second port B side. For example, as shown in FIGS. 3 and 4, when the spool 20 moves slightly from the standby position S1 on the first port A side to the first port A side, the spool 20 enters the control area S2 on the first port A side. Then, the first port A and the supply port P communicate with each other.

The biasing means 30 includes a first spring 31 and a second spring 32. The first spring 31 and the second spring 32 are arranged in the pair of pilot chambers 12, respectively. The first spring 31 and the second spring 32 are both compression coil springs, and are arranged so as to generate an initial biasing force at the neutral position S0 by being arranged in a predetermined compressed state.

The body 10 also includes a first stopper 33 that restricts the movement of the spool 20 at the neutral position S0 and a second stopper 34 that restricts the movement of the spool 20 at the standby position S1. The first spring 31 is held in a state where one end side is in contact with the first stopper 33 and the other end side is in contact with the second stopper 34. The other end of the first spring 31 is supported by the second spring 32 via the second stopper 34.

The pilot chamber 12 is provided with a first positioning portion 16 corresponding to the neutral position S0 and a second positioning portion 17 corresponding to the standby position S1. The first positioning portion 16 and the second positioning portion 17 are stepped portions provided so as to reduce the inner diameter of the pilot chamber 12.

The first stopper 33 is biased toward the spool 20 by the first spring 31 with an initial biasing force equal to the first threshold value TH1, and is pressed by the first positioning portion 16. The first stopper 33 is arranged by the first positioning portion 16 at a position substantially equal to the stroke direction end face of the spool 20 at the neutral position S0. The spool 20 is held at the neutral position S0 by the first stoppers 33 on both sides. The first stopper 33 does not move with an operating force equal to or less than the first threshold TH1 due to the initial biasing force, and when the operating force larger than the first threshold TH1 is applied to the spool 20, the first stopper 33 moves while compressing the first spring 31. To do. Since the first stopper 33 is pressed by the first positioning portion 16, the first stopper 33 functions as a wall surface that moves only when an operating force larger than the first threshold TH1 is applied to the spool 20.

The second stopper 34 is biased toward the spool 20 by the second spring 32 with an initial biasing force equal to the second threshold value TH2, and is pressed by the second positioning portion 17. The second stopper 34 is arranged to hold the spool 20 at the standby position S1 by the second positioning portion 17. That is, when the spool 20 moves and compresses the first spring 31, the first stopper 33 and the second stopper 34 come into contact with each other to reach the standby position S1 (see FIGS. 3 and 5). The second stopper 34 does not move with an operating force equal to or less than the second threshold TH2 due to the initial biasing force, and moves with compressing the second spring 32 when an operating force larger than the second threshold TH2 is applied to the spool 20. To do. Since the second stopper 34 is pressed by the second positioning portion 17, the urging force of the second spring 32 does not act on the first spring 31.

As shown in FIGS. 4 and 6, when an operating force larger than the second threshold value TH2 is applied to the spool 20, the spool 20, the first stopper 33, and the second stopper 34 come into contact with each other to form a second unit. The control area S2 for compressing the spring 32 is reached. In the control region S2, the compression amount of the second spring 32 (that is, the stroke amount of the spool 20) is proportional to the operating force larger than the second threshold value TH2.

The spring constant of the first spring 31 is smaller than the spring constant of the second spring 32. The first spring 31 is configured such that the generated biasing force is less than the second threshold TH2 even in the maximum compressed state (see FIGS. 3 to 6).

Each of the first stopper 33 and the second stopper 34 is provided with a through hole 35 for allowing hydraulic oil to pass therethrough. Therefore, when the hydraulic oil is supplied to the pilot chamber 12 to apply the operating force, the hydraulic oil causes the pilot oil pressure to act on the spool 20 through the through hole 35.

With such a configuration, the spool 20 moves to each of the neutral position S0, the standby position S1, and the control area S2.

<Opening operation of the 1st port>
When the first port A is opened (communication with the supply port P), first, as shown in FIG. 3, the spool 20 is moved to the standby position S1 on the first port A side. Specifically, hydraulic oil is supplied to the pilot chamber 12a from the pilot valve 2 (first port PA, see FIG. 2). An operating force F toward the first port A side is applied to the spool 20 by the pilot hydraulic pressure. The operating force F can be immediately (step function) increased to a predetermined first operating force F1 (see FIG. 7) by controlling the opening of the pilot valve 2. As a result, the spool 20 compresses the first spring 31 and quickly moves from the neutral position S0 to the standby position S1, and is stopped at the standby position S1 by the second stopper 34 and the second spring 32.

Next, the second operating force F2 (see FIG. 7) exceeding the second threshold value TH2 is applied to the spool 20 by controlling the opening of the pilot valve 2. As a result, the second spring 32 is compressed as shown in FIG. 4, and the spool 20 moves from the standby position S1 to the control area S2. In the control area S2, the supply port P and the first port A communicate with each other via the groove portion 22 of the spool 20, and proportional flow rate control is performed in which the opening area of the communicating portion is controlled according to the stroke amount of the spool 20. .. At this time, the second port B and the discharge port T communicate with each other via the groove portion 22 of the spool 20 and the bypass passage 24, and the hydraulic oil (return oil) flowing from the hydraulic cylinder 101 (see FIG. 1) into the second port B. ) Is discharged from the discharge port T.

<Opening operation of the 2nd port>
The same applies when the second port B is opened (communicated with the supply port P). As shown in FIG. 5, hydraulic oil is supplied from the pilot valve 2 (second port PB, see FIG. 2) to the pilot chamber 12b on the first port A side, and the first work toward the second port B side by the pilot hydraulic pressure. When the power F1 (see FIG. 7) is applied to the spool 20, the spool 20 compresses the first spring 31 and quickly moves from the neutral position S0 to the standby position S1.

Next, the second operating force F2 (see FIG. 7) exceeding the second threshold value TH2 is applied to the spool 20 by controlling the opening degree of the pilot valve 2, so that the second spring 32 is compressed as shown in FIG. The spool 20 moves from the standby position S1 to the control area S2. As a result, the supply port P and the second port B communicate with each other via the groove portion 22 of the spool 20, and the proportional flow rate control is started. At this time, the first port A and the discharge port T communicate with each other via the groove portion 22 of the spool 20 and the bypass passage 24, and the hydraulic oil (return flow) that flows from the hydraulic cylinder 101 (see FIG. 2) to the first port A side. Oil) is discharged from the discharge port T.

As described above, in the configuration in which the spool 20 of the main valve 1 moves from the neutral position S0 to the standby position S1, a sufficient seal can be secured between the neutral position S0 and the standby position S1, and therefore the standby position S1 is not provided. In comparison with the configuration in which the spool 20 is immediately moved to the control region S2 from the neutral position, the supply port P from the supply port P to the first port A or the second port B in the state where the spool 20 is in the neutral position (region C in FIG. 7). The leak of hydraulic oil can be effectively suppressed.

[Pilot valve]
Next, the structure of the pilot valve 2 of the flow control valve 100 will be described. As shown in FIG. 2, the pilot valve 2 applies a driving force in the stroke direction to the valve body 50 that moves in the stroke direction to change the valve opening degree of the pilot path 15 to the main valve 1. A solenoid 60 and a manual operation unit 70 that applies a driving force in the stroke direction to the valve element 50 or the movable piece 62 of the solenoid 60 by manual operation are included. The pilot valve 2 includes a valve body 50, a solenoid 60, and a body 40 that holds a manual operation unit 70.

A valve body chamber 41 in which the valve body 50 is arranged extends in the body 40 in the axial direction. The supply port PP, the discharge port PT, the first port PA, and the second port PB penetrate the body 40 from the outer periphery of the body 40 and communicate with the valve body chamber 41. The first port PA is arranged on one side (X1 side) and the second port PB is arranged on the other side (X2 side) around the supply port PP. The first port PA communicates with the pilot chamber 12a of the main valve 1 through the pilot path 15, and the second port PB communicates with the pilot chamber 12b through the pilot path 15.

The valve body 50 is configured by a spool that is slidable in the center axis direction (X direction) within the body 40 (valve body chamber 41). The X direction is the stroke direction of the valve body 50.

The valve body 50 is provided with an outer peripheral surface 51, which is a sliding surface, and a groove portion 52 for switching between the oil passages to communicate with each other. The basic structure of the valve body 50 is similar to that of the spool 20 of the main valve 1. The groove portion 22 is formed over the entire circumference in the circumferential direction of the valve body 50, and is arranged at the positions of the supply port PP and the discharge port PT at the neutral position (see FIG. 2). Two outer peripheral surfaces 51 between the respective groove portions 52 are formed so as to close the first port PA and the second port PB at the neutral position S0.

The valve body 50 selectively communicates the supply port PP with the first port PA or the second port PB via the groove 52 according to the amount of movement in the X direction. That is, the movement of the valve body 50 forms a communication point between the supply port PP and the first port PA or the second port PB via the groove portion 52. The valve body 50 adjusts the opening degree (opening area) of the communicating portion between the groove 52 and the first port PA or the second port PB according to the amount of movement in the X direction. By adjusting the opening degree, the pilot oil pressure of the hydraulic oil discharged from the first port PA or the second port PB is adjusted.

The solenoids 60 are provided on both sides of the valve body 50 in the axial direction of the body 40. Each solenoid 60 includes a coil 61 and a movable piece 62 that is an iron core (magnetic material) arranged inside the coil 61. The coil 61 is fixed to the body 40, and the movable piece 62 is provided so as to be movable in the stroke direction (X direction). The coil 61 applies a driving force (electromagnetic force) in the stroke direction to the movable piece 62 in response to the current supply from the controller 106 (see FIG. 1). The driving force of the coil 61 is proportional to the supply current from the controller 106. As a result, the solenoid 60 applies a driving force in the stroke direction to the valve body 50 via the movable piece 62. In the example of FIG. 2, the movable piece 62 of each solenoid 60 is coupled to the end portion of the valve body 50 in the stroke direction. Therefore, the driving force applied to the movable piece 62 by the coil 61 becomes the driving force in the stroke direction of the valve body 50 as it is.

When a current is supplied to the solenoid 60 on one side (X1 side) from the neutral state, a driving force toward the other side (X2 side) acts on the valve body 50, and the valve body 50 moves in the X2 direction to be supplied. The port PP and the second port PB communicate with each other. The hydraulic oil in the supply port PP is reduced in pressure from the pressure in the supply port PP to a pressure according to the opening area of the second port PB by the valve body 50, and then flows into the second port PB. The second port PB communicates with the hydraulic chamber 42b on the X2 side, and the valve body 50 opposes the driving force of the solenoid 60 by the hydraulic pressure of the hydraulic oil supplied to the hydraulic chamber 42b through the second port PB. Pushed to the side. The opening degree of the valve body 50 is adjusted by the balance between the driving force of the solenoid 60 and the hydraulic pressure of the hydraulic chamber 42b, and the pilot pressure proportional to the driving force is supplied to the second port PB (the stroke amount of the valve body 50. ) Is maintained. As a result, the hydraulic oil passing through the second port PB is supplied to the pilot chamber 12b of the main valve 1 via the pilot path 15 and moves the spool 20 of the main valve 1 to the second port B side.

Similarly, when a current is supplied to the other solenoid (X2 side) 60, a driving force toward one (X1 side) acts on the valve body 50, the valve body 50 moves in the X1 direction, and the supply port The PP communicates with the first port PA. The first port PA communicates with the hydraulic chamber 42a on the X1 side, and the opening of the valve body 50 is adjusted by the balance between the driving force of the solenoid 60 and the hydraulic pressure of the hydraulic chamber 42a. The opening degree (stroke amount of the valve body 50) supplied to the 1-port PA is maintained. As a result, the hydraulic oil passing through the first port PA is supplied to the pilot chamber 12a of the main valve 1 via the pilot path 15 and moves the spool 20 of the main valve 1 to the first port A side.

The manual operation parts 70 are provided at both ends of the body 40 in the stroke direction (X direction). In the example of FIG. 2, the manual operation unit 70 is provided integrally with a cover that covers the end of the body 40 in the stroke direction. The manual operation unit 70 on one side (X1 side) and the manual operation unit 70 on the other side (X2 side) have the same configuration and are symmetrical in the X direction. Therefore, in the following, the structure of the manual operation unit 70 on one side (X1 side) will be described as a representative.

As shown in FIG. 8, the manual operation part 70 includes a grip part 71, an elastic member 72, and a guide part 80 (see FIG. 10). Further, the manual operation part 70 includes a cover part 73 having a guide part 80 formed therein. A substantially cylindrical cover portion 73 is provided so as to project outward from the end surface of the body 40 in the stroke direction.

The grip portion 71 is provided so as to cover the end portion of the cover portion 73. The grip portion 71 is a cylindrical (cup-shaped) member having one end open and the other end closed, and the cylindrical end of the cover 73 is slidably inserted. This covers the end of the cover portion 73. The grip portion 71 is provided so as to be movable relative to the cover portion 73. The grip 71 is movable in the stroke direction (X direction) and the rotation direction around the stroke direction. The grip portion 71 moves relative to the cover portion 73 when the user grips and operates the grip portion 71. The grip portion 71 is a handle that can be operated by gripping a cylindrical outer peripheral surface, and preferably has an outer peripheral surface (see FIG. 10) that has been subjected to anti-slip processing such as knurling.

The grip portion 71 is provided with a rod 74 extending in the stroke direction toward the body 40 side so as to pass through the central axis. The rod 74 is arranged inside the cover portion 73 via an insertion opening 73a that opens at the end of the cover portion 73, and is provided so as to be movable in the stroke direction together with the grip portion 71. The rod 74 is disposed in the internal space 73b of the cover portion 73 and has a tip end portion to which a support portion 75 that supports the end portion of the elastic member 72 is attached.

Here, the movable piece 62 of the solenoid 60 is provided so as to project from the end portion of the body 40 into the internal space 73b of the cover portion 73. A cap 63 capable of supporting the end of the elastic member 72 is attached to the end of the movable piece 62. In the internal space 73b of the cover portion 73, the end portion (cap 63) of the movable piece 62 and the tip portion (support portion 75) of the rod 74 are provided so as to face each other with a space in the stroke direction.

The elastic member 72 is configured to generate a driving force according to the movement amount St of the grip portion 71 in the stroke direction. The elastic member 72 is configured to generate a repulsive force (restoring force) in the stroke direction by compression, and this repulsive force serves as a driving force for the valve body 50 (the movable piece 62 of the solenoid 60). The elastic member 72 is specifically configured by a compression coil spring. The elastic member 72 may be a spring member other than the compression coil spring, or may be an elastic body such as rubber.

The elastic member 72 has a cylindrical shape. The columnar tip of the support portion 75 and the columnar tip of the cap 63 are inserted into the elastic member 72 from the ends of the elastic member 72, respectively. Accordingly, the elastic member 72 is held between the support portion 75 and the cap 63 so as to be compressible in the stroke direction. The support portion 75 and the cap 63 each have a flange portion (spring receiving portion) FR whose root portion has an enlarged diameter, and the flange portion FR can compress the elastic member 72 in the stroke direction.

At the initial position Q0 of the grip portion 71 shown in FIG. 8, the distance D1 between the support portion 75 and each flange portion FR of the cap 63 (hereinafter, referred to as inter-flange distance) is larger than the natural length Ls of the elastic member 72. The difference D2 between the inter-flange distance D1 and the natural length Ls at the initial position Q0 is larger than the position variation width of the movable piece 62 due to the pressure variation supplied to the pilot valve 2 (supply port PP). That is, the manual operation unit 70 has a play (dead zone) of the difference D2 in the stroke direction. Therefore, the manual operation unit 70 does not apply a driving force to the valve body 50 or the movable piece 62 at the initial position Q0 of the grip 71.

As shown in FIG. 9, in a state in which the grip portion 71 moves in the stroke direction together with the rod 74 and the inter-flange distance D3 is smaller than the natural length Ls of the elastic member 72, the elastic member 72 has the support portion 75 and the cap 63. Compressed between and. As a result, the elastic member 72 generates a driving force that moves the movable piece 62 (valve body 50) in the stroke direction. The elastic member 72 generates a driving force proportional to the movement amount St of the grip portion 71 in the stroke direction at a position where the distance D1 between the flanges is smaller than the natural length Ls of the elastic member 72. The magnitude of the driving force generated by the elastic member 72 depends on the spring constant of the elastic member 72. The elastic constant of the elastic member 72 is set so that the range of variation of the driving force in the movable range of the grip portion 71 in the stroke direction matches or approximates the range of the driving force that can be generated by the solenoid 60. As a result, the valve body 50 can be driven by the driving force generated by the elastic member 72 instead of the solenoid 60 in the same manner as when the solenoid 60 is used, and the opening degree of the main valve 1 can be controlled.

FIG. 9 shows a position where the grip portion 71 moves to the end portion in the stroke direction (a second position Q2 described later) and the pilot valve 2 has the maximum opening degree. At this time, the distance between the support portion 75 and the cap 63 is the minimum distance D3 between the flanges, but the tip end of the support portion 75 and the tip end of the cap 63 are separated by a distance D4. As described above, in the manual operation part 70, the grip part 71 (rod 74, support part 75) does not directly contact and press the movable piece 62 (cap 63) of the solenoid 60.

Here, the grip portion 71 does not simply move linearly in the stroke direction, but is configured to be movable only along the track along the guide portion 80. Specifically, as shown in FIG. 10, the guide portion 80 is configured by a linear concave portion (groove portion) formed in a predetermined locus on the outer peripheral surface of the cover portion 73. A guide member 76 provided in a screw hole penetrating inward from the outer periphery of the grip portion 71 is inserted into the guide portion 80 (see FIG. 8), so that the grip portion 71 engages with the guide portion 80. .. As a result, the grip portion 71 can be moved along the path for moving the guide member 76 along the guide portion 80. The guide member 76 is formed with a screw portion that is screwed into the screw hole of the grip portion 71, and the guide member 76 is fixed to the grip portion 71.

As shown in FIG. 11, the guide portion 80 is configured to guide the grip portion 71 from the initial position Q0 to a position passing through the first position Q1 and beyond the first position Q1. Then, the guide portion 80 moves (Mv1, Mv2) along the guide portion 80 of the grip portion 71 between at least one of the initial position Q0 and the first position Q1 and the region beyond the first position Q1. In contrast, the movement amount St in the stroke direction is configured to be small.

As will be described later, in the present embodiment, the movement amount St2 in the stroke direction becomes smaller than the movement amount Mv2 along the guide portion 80 of the grip portion 71 in the area beyond the first position Q1. In the present embodiment, between the initial position Q0 and the first position Q1, the movement amount Mv1 of the grip portion 71 along the guide portion 80 and the movement amount St1 in the stroke direction match.

Specifically, the guide portion 80 includes a first guide portion 81 for guiding the grip portion 71 from an initial position Q0 in the stroke direction to a first position Q1, and a first position Q1 to a second position Q2 at the end in the stroke direction. And a second guiding portion 82 for guiding. The initial position Q0, the first position Q1 and the second position Q2 may be considered as the position coordinates of the gripper 71 in the stroke direction. The initial position Q0 is a position farthest from the body 40 in the stroke direction, and is a position where the driving force is not applied to the valve body 50 by the manual operation unit 70. The first position Q1 is located closer to the body 40 than the initial position Q0 in the stroke direction, and is a position where the driving force is applied to the valve body 50 by the manual operation unit 70. The second position Q2 is a movement limit to the body 40 side in the stroke direction, and is a position corresponding to the maximum opening degree in the opening adjustment of the valve body 50 by the manual operation unit 70.

The grip portion 71 (guide member 76) is movable from the initial position Q0 to the first position Q1 along a trajectory along the first guide portion 81. The first guide portion 81 is connected to the second guide portion 82 at the first position Q1. The grip portion 71 (guide member 76) is movable from the first position Q1 to the second position Q2 along a trajectory along the second guide portion 82.

The first guide portion 81 is formed so as to extend along the stroke direction (X direction). Therefore, between the initial position Q0 and the first position Q1, the grip portion 71 (guide member 76) linearly moves in the stroke direction along the first guide portion 81. As a result, between the initial position Q0 and the first position Q1, the movement amount Mv1 of the grip portion 71 along the guide portion 80 and the movement amount St1 in the stroke direction match.

On the other hand, the second guide portion 82 is configured to guide the grip portion 71 in a direction inclined with respect to the stroke direction. The second guide portion 82 is formed so as to extend in a direction inclined in the rotational direction with respect to the stroke direction. Therefore, between the first position Q1 and the second position Q2, the grip portion 71 (guide member 76) moves along the second guide portion 82 in an oblique direction that is a combined direction of the stroke direction and the rotation direction. .. That is, in the second guide portion 82, the user moves the grip portion 71 to the second position Q2 by moving the grip portion 71 in the stroke direction while twisting the grip portion 71 in the rotation direction. As shown in FIG. 12, the second guide portion 82 is provided in the range of the angle θ in the rotation direction, and the grip portion 71 is rotated by the angle θ (>0 degree) along the second guide portion 82. It

With such a configuration, in the area beyond the first position Q1 shown in FIG. 11, the movement amount St2 in the stroke direction is smaller than the movement amount Mv2 along the guide portion 80 (second guide portion 82) of the grip portion 71. Get smaller.

Further, the guide portion 80 includes the third guide portion 83 at the initial position Q0 in the stroke direction. The third guide portion 83 moves from the first regulation position Q0A that regulates the movement of the grip portion 71 in the stroke direction to the first movable position Q0B that permits the movement in the stroke direction while maintaining the initial position Q0 in the stroke direction. It is configured to guide the movement of the grip portion 71. That is, the third guide portion 83 is configured by a groove portion that extends along the rotational direction between the first regulation position Q0A and the first movable position Q0B. The third guide portion 83 is connected to the first guide portion 81 at the first movable position Q0B.

At the initial position Q0 in the stroke direction, the user strokes the grip portion 71 for the first time by rotating (twisting) the grip portion 71 (guide member 76) so as to move from the first regulation position Q0A to the first movable position Q0B. It is possible to move in the direction.

Further, as shown in FIG. 8, the manual operation part 70 includes a biasing member 77 that biases the grip part 71 in a direction from the first movable position Q0B to the first regulation position Q0A. The biasing member 77 is housed in the grip portion 71 and is arranged between the grip portion 71 and the cover portion 73. The biasing member 77 is specifically configured by a torsion coil spring, one end thereof is fixed to the grip portion 71, and the other end thereof is fixed to the cover portion 73. Then, the biasing member 77 biases the grip portion 71 with respect to the cover portion 73 in a direction toward the first regulation position Q0A. Accordingly, at the initial position Q0 in the stroke direction, the grip portion 71 is positioned at the first regulation position Q0A by the biasing force of the biasing member 77 unless the user operates the grip portion 71 in the rotational direction. The user can operate the grip portion 71 in the stroke direction by rotating the grip portion 71 to the first movable position Q0B against the biasing force of the biasing member 77.

Further, as shown in FIG. 11, the guide portion 80 includes a fourth guide portion 84 at the second position Q2 in the stroke direction. The fourth guide portion 84 moves from the second movable position Q2B that allows the grip portion 71 to move in the stroke direction to the second regulation position Q2A that restricts the movement in the stroke direction while maintaining the second position Q2 in the stroke direction. It is configured to guide the movement of the grip portion 71. That is, the fourth guide portion 84 is configured by a groove portion that extends along the rotation direction between the second movable position Q2B and the second regulation position Q2A. The fourth guide portion 84 is connected to the second guide portion 82 at the second movable position Q2B.

At the second position Q2 in the stroke direction, the user moves the grip portion 71 (guide member 76) from the second movable position Q2B to the second regulation position Q2A, so that the position of the grip portion 71 in the stroke direction is the second position. It becomes possible to fix it to Q2. That is, the operation can be fixed in the state where the pilot valve 2 is at the maximum opening (the state where the pilot hydraulic pressure supplied to the main valve 1 is maximized).

The first regulation position Q0A of the third guide portion 83 and the second regulation position Q2A of the fourth guide portion 84 are on the same side in the rotational direction with respect to the first movable position Q0B and the second movable position Q2B, respectively. It is provided in. Therefore, the biasing member 77 biases the grip portion 71 toward the first regulation position Q0A at the initial position Q0, and biases the grip portion 71 toward the second regulation position Q2A at the second position Q2. Is configured.

As a result, at the second position Q2 in the stroke direction, the gripper 71 is prevented from moving to the second movable position Q2B unless the user operates the gripper 71 in the rotational direction. The user can operate the grip portion 71 in the stroke direction by rotating the grip portion 71 to the second movable position Q2B against the biasing force of the biasing member 77.

In the manual operation part 70, the fourth guide part 84, the second guide part 82, the first guide part 81, and the third guide part 83 are gripped in this order from the second position Q2 to the initial position Q0 via the first position Q1. By moving the portion 71, the opening degree of the pilot valve 2 can be changed in the direction of narrowing it.

(Relationship between guide part and main valve opening change)
In the present embodiment, when the manual operation part 70 is operated to move the grip part 71 from the initial position Q0 to the first position Q1, the valve body 50 moves via the elastic member 72, and the stroke direction of the grip part 71. The pilot hydraulic pressure is supplied at an opening degree according to the movement amount St of.

The pilot valve 2 moves the valve body 50 to a valve opening degree at which the spool 20 of the main valve 1 moves to the standby position S1 (see FIGS. 3 and 5) when the grip portion 71 moves to the first position Q1. Is configured. That is, the pilot hydraulic pressure supplied by the opening degree corresponding to the movement amount St1 in the stroke direction from the initial position Q0 to the first position Q1 is the first operating force F1 (FIG. 7) when the spool 20 moves to the standby position S1. The movement amount St1 in the stroke direction (that is, the length of the first guide portion 81) is set so as to generate the reference position.

Therefore, the user can accurately switch the main valve 1 (spool 20) to the standby position S1 (see FIGS. 3 and 5) simply by pushing the grip portion 71 straight in the stroke direction to the first position Q1.

Further, the pilot valve 2 has a valve opening degree that allows the spool 20 of the main valve 1 to move to the control area S2 (see FIGS. 4 and 6) when the grip portion 71 moves to the area beyond the first position Q1. It is configured to move the valve body 50. That is, the fluctuation range of the pilot hydraulic pressure supplied by the opening degree corresponding to the movement amount St2 in the stroke direction between the first position Q1 and the second position Q2 is such that the main valve 1 controls the flow rate of the hydraulic oil in the control region S2. The movement amount St2 in the stroke direction (that is, the length of the second guide portion 82) is set so as to match the pressure range for proportional control. That is, in the present embodiment, the flow rate control in the control region S2 of the main valve 1 is possible within the range in which the grip portion 71 is moved along the second guide portion 82.

In the second guide portion 82, the movement amount St2 in the stroke direction is smaller than the movement amount Mv2 (actual operation amount) along the guide portion 80 (second guide portion 82) of the grip portion 71 (see FIG. 7). Therefore, the flow rate of the main valve 1 can be precisely controlled during the manual operation.

[Effects of this embodiment]
In this embodiment, the following effects can be obtained.

In the present embodiment, as described above, when the grip portion 71 is moved by the manual operation, the stroke direction with respect to the movement amount Mv2 along the guide portion 80 in the area beyond the first position Q1 of the grip portion 71. The movement amount St2 of is decreased. That is, an area in which the movement amount St2 in the stroke direction that contributes to the change in the valve opening degree is smaller than the distance (actual operation amount) Mv2 in which the user actually moves the grip portion 71 along the guide portion 80, It is provided on the movement path of the grip portion 71. Therefore, even when the user unintentionally moves the grip portion 71 by a large amount, the valve opening degree of the pilot path 15 can be changed to be smaller than the actual operation amount, so that the main valve can be manually operated. The valve opening of No. 1 can be finely controlled. As a result, it is possible to prevent unintentional sudden opening adjustment during manual operation. Further, in the region (Q1-Q2) where the movement amount St in the stroke direction is smaller than the movement amount along the guide portion 80, fine opening adjustment is possible even though it is a manual operation, so even during manual operation. It is possible to perform precise opening degree adjustment (flow rate control) close to the control when the solenoid 60 is made to function. Note that this effect is obtained even when the movement amount St1 in the stroke direction is smaller than the movement amount Mv1 along the guide portion 80 between the initial position Q0 and the first position Q1 of the grip portion 71. , Can be obtained as well.

In the present embodiment, as described above, the guide portion 80 includes the first guide portion 81 and the second guide portion 82, and the second guide portion 82 has the grip portion in the direction inclined with respect to the stroke direction. Since the guide portion 71 is configured to be guided, a simple configuration in which the grip portion 71 is guided in a direction inclined with respect to the stroke direction can be performed with respect to the movement amount Mv2 of the grip portion 71 along the guide portion 80. Thus, the movement amount St2 in the stroke direction can be reduced. Further, the larger the tilt angle θ of the guide direction with respect to the stroke direction, the smaller the movement amount St in the stroke direction can be made relatively small. Therefore, the relationship between the movement amount St in the stroke direction and the actual operation amount can be easily set. be able to.

In the present embodiment, as described above, the first guide portion 81 is formed to extend along the stroke direction (X direction), and the second guide portion 82 is a direction inclined in the rotational direction with respect to the stroke direction. Since the second guide portion 82 is formed so as to extend, the user performs an operation of moving the grip portion 71 in the stroke direction while twisting the grip portion 71 in the rotation direction. According to the combined operation of the twisting operation and the pushing operation, it is possible to effectively prevent the operation amount from being erroneous as compared with the operation of simply pushing the grip portion 71. Further, considering the operation control of the hydraulic cylinder 101, for example, the second guide portion 82 (where the valve opening degree is larger than the first guide portion 81 (from the initial position Q0 to the first position Q1) where the valve opening degree is small ( In the control from the first position Q1 to the terminal second position Q2), since the expansion/contraction speed of the hydraulic cylinder 101 increases and delicate control is required, the actual operation amount (in the second guide portion 82 where the valve opening increases) ( The above-described configuration that can reduce the movement amount St2 in the stroke direction with respect to Mv2) is useful.

In the present embodiment, as described above, the guide portion 80 allows movement in the stroke direction from the first regulation position Q0A that regulates movement of the grip portion 71 in the stroke direction while maintaining the initial position Q0 in the stroke direction. Since the third guide portion 83 for guiding the movement of the grip portion 71 to the first movable position Q0B is included, the opening adjustment by the manual operation is prohibited at the first regulation position Q0A at the initial position Q0, and the first regulation position Q0A. It is possible to adjust the opening degree manually by operating the gripper 71 from the first to the first movable position Q0B. Therefore, it is possible to prevent the user from accidentally moving the grip 71 to perform a manual operation without providing a cover or a complicated safety mechanism for preventing the grip 71 from touching.

In the present embodiment, as described above, since the manual operation unit 70 includes the biasing member 77 that biases the grip portion 71 in the direction from the first movable position Q0B to the first regulation position Q0A, the user is biased. Unless the grip portion 71 is intentionally moved to the first movable position Q0B against the biasing force of the member 77, the opening degree is not manually adjusted. As a result, it is possible to more reliably suppress the erroneous operation of the user.

In the present embodiment, as described above, the guide portion 80 restricts the movement in the stroke direction from the second movable position Q2B that allows the movement of the grip portion 71 in the stroke direction while keeping the second position Q2. Since the fourth guide portion 84 for guiding the movement of the grip portion 71 to the regulation position Q2A is included, when the grip portion 71 is moved to the second position Q2 to maximize the valve opening degree, the grip portion 71 is moved to the second position. By moving to the regulation position Q2A, it is possible to fix the second position Q2 (maximum opening) as it is and avoid returning to the first position Q1 side. Therefore, when it is desired to keep the maximum opening during the manual operation, the user does not have to continue to operate the grip portion 71, and the convenience of the flow control valve during the manual operation can be improved.

In the present embodiment, as described above, the main valve 1 has a structure in which the flow rate control is not performed between the neutral position S0 and the standby position S1, so that between the neutral position S0 and the control region S2. It is possible to effectively suppress the leak of the hydraulic oil. Further, when the grip portion 71 moves to the first position Q1, the valve body 50 is moved to a valve opening degree at which the spool 20 of the main valve 1 moves to the standby position S1, and the grip portion 71 exceeds the first position Q1. The pilot valve 2 is configured to move the valve body 50 to a valve opening degree at which the spool 20 of the main valve 1 moves to the control region S2 when it moves to a different region. By moving the portion 71 to the first position Q1, the main valve 1 can be placed in a standby state, and the flow rate control can be started from a region exceeding the first position Q1. When operating the grip portion 71, the actual operation amount of the grip portion 71 depending on whether the grip portion 71 is moved from the initial position Q0 to the first position Q1 or when the grip portion 71 is moved beyond the first position Q1. It is possible to change the opening change rate (movement amounts St1, St2 in the stroke direction) of the valve body 50 with respect to (Mv1, Mv2). Accordingly, even during manual operation, the user can easily grasp and operate up to which position in the movable range of the grip portion 71 is the standby position S1 and from which position is the control region S2.

[Modification]
It should be considered that the embodiments disclosed this time are exemplifications in all points and not restrictive. The scope of the present invention is shown not by the above description of the embodiments but by the scope of the claims, and further includes meanings equivalent to the scope of the claims and all modifications (modifications) within the scope.

For example, in the above embodiment, the example in which the standby position S1 is provided between the neutral position S0 and the control region S2 in the operating range of the spool 20 has been shown, but the present invention is not limited to this. In the present invention, unlike the main valve 201 according to the modification shown in FIG. 13, the standby position S1 does not have to be provided between the neutral position S0 and the control region S2. In this case, the pilot chamber 12 of the main valve 201 need only be provided with one spring 231 instead of the first spring 31 and the second spring 32.

In FIG. 13, since the standby position S1 is not provided between the neutral position S0 and the control area S2, if the spool 220 moves in the X2 direction from the neutral position S0, the control area S2 (second port B side) is immediately reached. When the spool 220 reaches the PB control state and moves in the X1 direction from the neutral position S0, the spool 220 immediately reaches the control area S2 (first port A side) and enters the PA control state.

In this case, in the manual operation unit 70 of the pilot valve 2 (see FIG. 11), the gripper 71 is moved from the initial position Q0 to the first position Q1 so that the spool 20 of the main valve 201 is quickly opened to a predetermined opening. It can be changed (stepwise). That is, in a low opening range in which the hydraulic cylinder 101 operates at a low speed, it is possible to change the opening gradually until a predetermined opening. While the grip portion 71 is moving from the first position Q1 to the second position Q2, the movement amount St2 in the stroke direction is smaller than the movement amount Mv2 along the guide portion 80 (second guide portion 82) of the grip portion 71. Since it becomes smaller, the flow rate of the main valve 1 can be precisely controlled during manual operation. That is, in the medium to maximum opening range in which the operation of the hydraulic cylinder 101 is accelerated, it is possible to perform precise opening control while suppressing a sudden change in opening even by manual operation.

Further, in the above-described embodiment, the guide portion 80 is in a region beyond the first position Q1 (second guide portion 82), and the movement amount in the stroke direction with respect to the movement amount Mv2 of the grip portion 71 along the guide portion 80. Although an example in which St2 is configured to be small has been shown, the present invention is not limited to this. In the present invention, as in the modified example shown in FIG. 14, the guide portion 80 moves the guide portion 80 along the guide portion 80 between the initial position Q0 and the first position Q1 (first guide portion 81). The movement amount St1 in the stroke direction may be smaller than Mv1. In FIG. 14, the first guide portion 81 is inclined with respect to the stroke direction, and the second guide portion 82 extends in the stroke direction. In this case, for example, in the example of the main valve 201 in FIG. 13, in the initial stage of the start of the manual operation, the movement amount St1 in the stroke direction with respect to the movement amount Mv1 along the guide portion 80 (second guide portion 82) of the grip portion 71. Therefore, even if the user is not familiar with the manual operation, it is possible to control the opening degree while suppressing a rapid change in the opening degree. After the manual operation is started, for example, when the hydraulic cylinder 101 is operated to a predetermined position, the maximum opening can be achieved by merely pushing the grip 71 in the stroke direction from the first position Q1 to the second position Q2, which is convenient. high.

In addition, as shown in FIG. 15, the guide portion 80 extends along the guide portion 80 of the grip portion 71 both between the initial position Q0 and the first position Q1 and in the region beyond the first position Q1. The movement amounts St1 and St2 in the stroke direction may be smaller than the movement amounts Mv1 and Mv2, respectively. That is, both the first guide portion 81 and the second guide portion 82 may be configured to guide the grip portion 71 in a direction inclined with respect to the stroke direction (X direction).

Further, in the above-described embodiment, the second guide portion 82 extends in the direction inclined in the rotation direction with respect to the stroke direction, so that the movement amount St in the stroke direction is smaller than the movement amount Mv along the guide portion 80. However, the present invention is not limited to this. When the movement amount St in the stroke direction is smaller than the movement amount Mv along the guide portion 80, the guide portion 80 may be inclined in any direction other than the stroke direction. The grip portion 71 may be guided in a direction inclined with respect to the stroke direction in the horizontal plane.

Further, in the above embodiment, an example in which the grip portion 71 is movable in the rotation direction by the angle θ in FIG. 12 has been shown, but the present invention is not limited to this. The size of the angle θ is not limited to the example shown in FIG. The rotation angle of the grip portion 71 is arbitrary. The grip 71 may rotate 360 degrees or more.

Further, as shown in FIG. 16, the guide portion 80 may guide the grip portion 71 in a direction orthogonal to the stroke direction (X direction). In FIG. 16, the second guide portion 82 is formed in a step shape including a portion extending in the stroke direction (X direction) and a portion extending in the rotation direction, and the movement amount St of the grip portion 71 in the stroke direction is calculated. It can be changed in steps.

Further, in the above-described embodiment, the example in which the urging member 77 that urges in the direction from the first movable position Q0B to the first regulation position Q0A is provided in the manual operation portion 70 has been shown, but the present invention is not limited to this. Absent. In the present invention, the biasing member 77 may not be provided.

Further, in the above embodiment, the example in which the guide portion 80 includes the third guide portion 83 has been shown, but the present invention is not limited to this. In the present invention, the third guide portion 83 may not be provided.

Further, in the above embodiment, the example in which the guide portion 80 includes the fourth guide portion 84 has been shown, but the present invention is not limited to this. In the present invention, the fourth guide portion 84 may not be provided.

Besides, in the above embodiment, the example in which the second guide portion 82 corresponds to the control region S2 of the main valve 1 is shown, but the present invention is not limited to this. For example, another guide part (fifth guide part) may be provided between the first guide part 81 and the second guide part 82. In this case, in the control area S2 of the main valve 1, the fifth guide portion is provided corresponding to the low to medium opening area, and the second guide portion 82 is provided corresponding to the middle to maximum opening area. You can The fifth guide portion and the second guide portion 82 may have different inclination angles with respect to the stroke direction.

Further, in the above embodiment, the valve body 50 of the pilot valve 2 is configured to integrally include the movable piece 62 of the solenoid 60, and the manual operation unit 70 causes the elastic member 72 to apply a driving force to the valve body 50. Although an example is shown, the present invention is not limited to this. In the present invention, the valve body 50 and the movable piece 62 of the solenoid 60 may be separate members, and the manual operation unit 70 may apply a driving force to the movable piece 62 by the elastic member 72. For example, by moving the movable piece 62 in the stroke direction by the elastic member 72 to change the size of the gap between the valve body 50 and the movable piece 62, the pressure in this gap is changed to move the valve body 50. Alternatively, the configuration may be made.

Further, in the above embodiment, the slide spool type pilot valve 2 in which the valve body 50 is a spool is shown, but the present invention is not limited to this. In the present invention, the valve body 50 may be the poppet type pilot valve 2 which is a poppet.

Further, although the biasing member 77 is an example in which the biasing member 77 is a torsion coil spring in the above embodiment, the present invention is not limited to this. In the present invention, the biasing member 77 may be made of a leaf spring or another elastic material.

Further, in the above-described embodiment, the example in which the grip portion 71 is configured by the cylindrical member that covers the cover portion 73 has been shown, but the present invention is not limited to this. The grip 71 may be, for example, a lever fixed to a cylindrical member.

1, 201 Main valve 2 Pilot valve 15 Pilot path 20, 220 Spool 50 Valve body 60 Solenoid 62 Movable piece 70 Manual operation part 71 Gripping part 72 Elastic member 77 Biasing member 80 Guide part 81 First guide part 82 Second guide part 83 3rd guide part 84 4th guide part 100 Flow control valve Mv1, Mv2 Movement amount along the guide part Q0 Initial position Q0A 1st restriction position Q0B 1st movable position Q1 1st position Q2 2nd position Q2A 2nd restriction position Q2B Second movable position S0 Neutral position S1 Standby position S2 Control area St (St1, St2) Movement amount in stroke direction

Claims (7)

It has a main valve and a pilot valve,
The pilot valve is a valve body that moves in a stroke direction to change a valve opening degree of a pilot path to the main valve, a solenoid that applies a driving force in the stroke direction to the valve body, and the valve is manually operated. A manual operation unit that applies a driving force in the stroke direction to a movable piece of the body or the solenoid,
The manual operation unit includes a grip unit, an elastic member that generates a driving force according to the amount of movement of the grip unit in the stroke direction, and a position that passes from the initial position to the first position and beyond the first position. A guide part for guiding the grip part,
The guide portion has at least one of a region between the initial position and the first position and a region beyond the first position in the stroke direction with respect to a movement amount of the grip portion along the guide portion. A flow control valve configured to reduce the amount of movement. The guide part includes a first guide part that guides the grip part from the initial position in the stroke direction to the first position, and a second guide part that guides the grip part from the first position to a second end position in the stroke direction. Part and
The flow rate control according to claim 1, wherein at least one of the first guide portion and the second guide portion is configured to guide the grip portion in a direction inclined with respect to the stroke direction. valve. The grip portion is movable in the stroke direction and a rotation direction around the stroke direction,
The first guide portion is formed to extend along the stroke direction,
The flow control valve according to claim 2, wherein the second guide portion is formed so as to extend in a direction inclined to the rotation direction with respect to the stroke direction. The guide part holds the initial position in the stroke direction at the grip position from a first restricting position that restricts the grip part to move in the stroke direction to a first movable position that allows movement in the stroke direction. The flow control valve according to claim 2 or 3, further comprising a third guide portion that guides movement of the portion. The flow control valve according to claim 4, wherein the manual operation portion further includes a biasing member that biases the grip portion in a direction from the first movable position to the first restricted position. The guide portion remains at the second position in the stroke direction, and moves from the second movable position that allows the grip portion to move in the stroke direction to the second restriction position that restricts movement in the stroke direction. The flow control valve according to any one of claims 2 to 5, further comprising a fourth guide portion that guides the movement of the grip portion. The main valve controls a spool that moves to a neutral position, a standby position that is a start point of opening control, and a control region in which the opening changes according to the spool movement amount according to the pressure from the pilot path. Have,
The pilot valve is
Moving the valve element to a valve opening degree at which the spool of the main valve moves to the standby position when the gripper moves to the first position,
The structure is configured to move the valve element to a valve opening degree at which the spool of the main valve moves to the control region when the grip portion moves to a region beyond the first position. The flow control valve according to any one of 1 to 6.

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