Flow Control Valve

Abstract

To provide a flow regulating valve capable of regulating a valve opening manually or using an electric motor while considering operationality and safety aspects.SOLUTION: A flow regulating valve 10 in which a needle valve 34 is arranged while facing a fluid passage 18 provided in a body 12 includes a handle 56 for manual rotation operation, a remote-controllable electric motor 58, and a power transmission mechanism for transmitting selectively the rotation operating force of the handle or the driving force of the electric motor to the needle valve. By moving the handle in the rotation-axis direction, the selective switching is performed.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a flow rate regulating valve that regulates a flow rate in a fluid passage. [Background technology]

[0002] It has been known in the past to provide a flow control valve (speed controller) whose flow path area can be manually adjusted in a flow path connecting the fluid pressure cylinder and a fluid supply source, or in a flow path connecting the fluid pressure cylinder and a discharge port, in order to adjust the speed of the fluid pressure cylinder, for example.

[0003] Also known is an electric needle valve, as disclosed in Patent Document 1, in which the valve opening is adjusted by an electric motor, enabling the flow rate of fluid supplied to an actuator to be remotely controlled. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent No. 5061258 Summary of the Invention [Problem to be solved by the invention]

[0005] Even for flow control valves that adjust the valve opening by driving an electric motor remotely, the valve opening must be adjusted manually and operation checked when starting up the equipment. Generally, the assembly process for production equipment is carried out in the following steps: mechanical assembly, pneumatic piping, electrical wiring, and program downloading to PLCs, etc., and only after the program download is completed can a remote control signal be sent to the electric motor. Operation checks while the equipment is running must be carried out at an earlier stage, which must be done manually.

[0006] Furthermore, remote operation via a PLC generally requires a system operator or software engineer. If the opening of the flow control valve cannot be adjusted manually, and the person performing maintenance on the equipment does not have the necessary skills for remote operation, the cooperation of the system operator or software engineer must be sought, which is time-consuming.

[0007] It is of course possible to provide a manual operating unit for a flow control valve that drives an electric motor to adjust the valve opening, but when using a small electric motor equipped with a reducer with a large reduction ratio, manual operation becomes difficult when the operating unit is connected to the electric motor on the driven side of the reducer.

[0008] As described above, there is a demand for a flow control valve that can adjust the valve opening degree both manually and with an electric motor, but a practical one has not yet been fully developed. The present invention aims to provide a flow control valve that can adjust the valve opening degree both manually and with an electric motor (especially a small electric motor), and that also takes into consideration operability and safety. [Means for solving the problem]

[0009] The flow control valve of the present invention has a needle valve disposed facing a fluid passage provided in the main body, and is equipped with a handle for manual rotational operation, an electric motor that can be remotely controlled, and a power transmission mechanism that selectively switches between the rotational operating force of the handle and the driving force of the electric motor and transmits them to the needle valve, with the switching being performed by moving the handle in the direction of the rotation axis.

[0010] The flow control valve described above allows easy manual handle operation regardless of the specifications of the electric motor. In addition, the handle's rotational operating force and the driving force of the electric motor can be selectively switched by the push-pull action of moving the handle in the direction of the rotation axis, providing good operability. Furthermore, the handle is not rotated by the electric motor, ensuring the safety of workers on site. Effect of the Invention

[0011] The flow control valve according to the present invention is equipped with a power transmission mechanism that selectively switches between the rotational operating force of the handle and the driving force of the electric motor and transmits them to the needle valve, so that manual handle operation can be easily realized regardless of the specifications of the electric motor, and the safety of workers on site is ensured. In addition, the above switching can be performed by the push-pull operation of moving the handle in the direction of the rotation axis, so operability is good. [Brief description of the drawings]

[0012] [Figure 1] 1 is a cross-sectional view of a flow rate regulating valve according to an embodiment of the present invention when the handle is at the lowest position and the valve opening degree is at a maximum (fully open state). FIG. [Diagram 2] 2 is a cross-sectional view of the flow rate regulating valve of FIG. 1 when the handle is at the lower limit position and the valve opening degree is zero (fully closed state). [Diagram 3] FIG. 2 is a diagram showing the flow rate regulating valve of FIG. 1 exploded into parts or parts groups. [Figure 4] 2 is a cross-sectional view of a main portion of the flow rate regulating valve of FIG. 1 when the handle is in an upper limit position. [Diagram 5] 2 is a cross-sectional view of a main portion of the flow rate regulating valve of FIG. 1 in a state in which a handle is being pressed down from an upper limit position to a lower limit position. [Figure 6] 2 is a cross-sectional view of a main portion of the flow rate regulating valve of FIG. 1 in a state in which a handle is being raised from a lower limit position to an upper limit position. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] A flow control valve according to the present invention will be described with reference to a preferred embodiment and the accompanying drawings. The flow control valve 10 is used to adjust the flow rate of a fluid such as compressed air. In the following description, when words related to directions such as up, down, left, and right are used, they refer to directions on the drawings for convenience and do not limit the actual arrangement of each component.

[0014] 1 and 3, the flow rate control valve 10 includes a main body 12, a cover 14, a valve seat body 28, a needle valve 34, a handle 56, a stepping motor (electric motor) 58, and a power transmission mechanism. The power transmission mechanism is a mechanism that selectively switches between the rotational operating force of the handle 56 and the driving force of the stepping motor 58 and transmits them to the needle valve 34, and will be described in detail later. The stepping motor 58 has a built-in reducer (not shown). In this embodiment, the stepping motor 58 is used as the electric motor, but other types of electric motors may be used.

[0015] The box-shaped main body 12 has an accommodation chamber 40 which cooperates with the cover 14 to accommodate a stepping motor 58 and a power transmission mechanism. The cover 14 is attached to a support frame 60, which will be described later. The top surface of the cover 14 is recessed downward at a position toward the center in the longitudinal direction. The center of the bottom surface of this recess 14a is open, and a cylindrical handle support part 16 is provided integrally with the cover 14, rising upward from the edge of the opening.

[0016] A fluid passage 18 that is open at both ends and extends in the left-right direction is provided in the lower part of the main body 12. A first port 20 that opens at one end of the fluid passage 18 and a second port 22 that opens at the other end of the fluid passage 18 are each connected to an external pipe (not shown). In this embodiment, the flow rate of the fluid flowing from the first port 20 to the second port 22 can be adjusted by the action of a check valve 30 (described later).

[0017] The valve seat body 28 and the needle valve 34 are disposed in a manner intersecting the fluid passage 18, and a cylindrical guide wall 24 for guiding the fluid is provided in the longitudinal center of the fluid passage 18 so that its axis is aligned with that of the valve seat body 28 and the needle valve 34. The guide wall 24 is provided with a first window portion 24a and a second window portion 24b in an upper portion near the first port 20 and a lower portion near the second port 22, respectively, and the first port 20 is connected to the second port 22 via the first window portion 24a and the second window portion 24b. The guide wall 24 extends toward the accommodation chamber 40, and the extension portion forms a support wall 26 that supports the valve seat body 28.

[0018] The cylindrical valve seat body 28 is fitted and fixed to the inside of the support wall 26 of the main body 12 at a support part 28a in the longitudinal center. A needle valve 34 is inserted and arranged inside the valve seat body 28 so as to be movable in the X direction, which is the axial direction of the needle valve 34. The tip of the needle valve 34 faces the fluid passage 18, and a tapered surface 34a is formed on the outer periphery near the tip.

[0019] A plurality of horizontal holes 28b penetrating the side wall of the valve seat body 28 are provided below the support portion 28a of the valve seat body 28. A valve seat 28c capable of abutting against the tapered surface 34a of the needle valve 34 is provided inside the valve seat body 28 below the horizontal holes 28b. When the needle valve 34 is separated from the valve seat 28c, the first window portion 24a and the second window portion 24b communicate with each other through the horizontal holes 28b of the valve seat body 28 and the lower end opening portion 28e of the valve seat body 28. As shown in FIG. 2, when the needle valve 34 abuts against the valve seat 28c, the communication between the first window portion 24a and the second window portion 24b through the horizontal holes 28b of the valve seat body 28 and the lower end opening portion 28e of the valve seat body 28 is blocked.

[0020] A check valve 30 capable of being pressed against the inner circumference of the guide wall 24 of the main body 12 is attached to the outer periphery of the lower end of the valve seat body 28. The check valve 30 blocks the flow of fluid from the first window 24a to the second window 24b through the gap between the lower end of the valve seat body 28 and the guide wall 24, and allows the flow in the opposite direction. Therefore, when the needle valve 34 is in contact with the valve seat 28c, the flow of fluid from the first port 20 to the second port 22 is blocked, and when the needle valve 34 is separated from the valve seat 28c, the fluid flows from the first port 20 to the second port 22 at a flow rate corresponding to the flow path area that changes according to the separation distance.

[0021] A cylindrical collar 38 that supports the upper end of the needle valve 34 is fixed to the inner surface of the valve seat body 28 at a position above the support portion 28a. Two sets of flat surfaces 34c and 38a that abut against each other are formed on the outer periphery of the needle valve 34 and the inner periphery of the collar 38. As a result, the needle valve 34 is supported by the collar 38 so that rotation around the axis is restricted and movement in the axial direction is possible. In this embodiment, two sets of flat surfaces are used as a means for preventing the needle valve 34 from rotating relative to the collar 38, but a single set of flat surfaces (D cut), splines, or other means may also be used.

[0022] An annular seal member 32 is attached to the outer periphery of the support portion 28a of the valve seat body 28, which abuts against the inner periphery of the support wall 26 of the main body 12. An annular needle packing 36 is attached to the outer periphery of the needle valve 34, which slides against the inner periphery of the support portion 28a of the valve seat body 28. The fluid passage 18 is airtightly separated from the accommodation chamber 40 by the seal member 32 and the needle packing 36. Since the needle valve 34 is not rotated around its axis, the load on the needle packing 36 is reduced, and the durability of the needle packing 36 is improved.

[0023] The power transmission mechanism includes the feed screw 42, the stem 44, the handle presser 46, the valve gear 48, and the motor gear 50. The rotational operating force of the handle 56 is transmitted to the needle valve 34 via the handle presser 46, the stem 44, and the feed screw 42, and the driving force of the stepping motor 58 is transmitted to the needle valve 34 via the motor gear 50, the valve gear 48, the stem 44, and the feed screw 42. In other words, the power transmission path between the handle 56 and the needle valve 34 is formed by the handle presser 46, the stem 44, and the feed screw 42, and the power transmission path between the stepping motor 58 and the needle valve 34 is formed by the motor gear 50, the valve gear 48, the stem 44, and the feed screw 42. The power transmission mechanism will be described in detail below.

[0024] The feed screw 42 has a flange 42a in the center in the longitudinal direction, and a male thread 42b on the outer periphery below the flange 42a. The feed screw 42 is rotatably supported above the flange 42a by a bearing 52 provided in the upper end opening 28d of the valve seat body 28. The upper end of the feed screw 42 protrudes upward from the bearing 52 and fits inside a cylindrical portion 44b of a stem 44, which will be described later.

[0025] A bottomed screw hole 34b that opens at the upper end side is provided inside the needle valve 34, and the lower part of the feed screw 42 screws into this screw hole 34b. The feed screw 42 is disposed in such a manner that the flange 42a is sandwiched between the lower surface of the bearing 52 and the upper surface of the collar 38, and the movement of the feed screw 42 in the X direction, which is the axial direction, is restricted. When the feed screw 42 rotates, the needle valve 34, whose rotation around the axis is restricted, moves in the axial direction.

[0026] The stem 44 includes a plate-like flange portion 44a extending horizontally, a cylindrical portion 44b extending downward from the flange portion 44a and opening at its tip, and a protruding portion 44c protruding upward from the flange portion 44a. The cylindrical portion 44b of the stem 44 is connected to the upper end of the feed screw 42 by a predetermined rotation prevention means, so that the feed screw 42 rotates integrally with the stem 44, and the stem 44 is movable in the X direction, which is the axial direction, relative to the feed screw 42. In this embodiment, two sets of flat portions are used as the rotation prevention means, but a set of flat portions (D cut), splines, or other means may also be used.

[0027] The upward movement of the stem 44 is restricted by abutment of a flange portion 44a of the stem 44 against a step portion 16a protruding from the inner circumference of the handle support portion 16 of the cover 14. A spline 44d that engages with a spline 48d of a valve gear 48, which will be described later, is provided on the outer circumference of the upper end side of the cylindrical portion 44b of the stem 44 (see FIG. 4). A handle presser 46 is fixed to the protruding portion 44c of the stem 44 by a mounting screw 54. A spline 46a that engages with a first spline 56f of a handle 56, which will be described later, is formed on the outer circumference of the handle presser 46 (see FIG. 5).

[0028] The handle 56 is composed of an annular seat portion 56a, an outer cylindrical portion 56b extending downward from the outer periphery of the seat portion 56a, and an inner cylindrical portion 56c extending downward from the inner periphery of the seat portion 56a. A rib 56d protruding toward the inner periphery is provided at the lower end of the outer cylindrical portion 56b, and a flange 56e extending toward the inner periphery is provided at the lower end of the inner cylindrical portion 56c. As shown in FIG. 4, a first spline 56f that engages with the spline 46a of the handle presser 46 is formed on the inner periphery near the lower end of the inner cylindrical portion 56c. In addition, a second spline 56g that engages with the spline 16d formed on the inner periphery of the handle support portion 16 of the cover 14 is formed on the outer periphery near the upper end of the inner cylindrical portion 56c.

[0029] The handle 56 is capable of push-pull operation and can move in the X direction, which is the direction of its rotation axis, i.e., up and down, between an upper limit position (upward movement limit) and a lower limit position (downward movement limit) described below. When the upper surface of the flange 56e of the handle 56 abuts against the lower surface of the handle presser 46 to pull up the handle presser 46, and the flange portion 44a of the stem 44, which moves integrally with the handle presser 46, abuts against the step portion 16a of the handle support portion 16, the handle 56 reaches the upper limit position (see FIG. 4).

[0030] The handle support part 16 fits into the space between the inner tubular part 56c and the outer tubular part 56b of the handle 56, and when the lower surface of the seat part 56a of the handle 56 abuts against the upper end of the handle support part 16, the handle 56 reaches its lower limit position (see FIG. 1). When the handle 56 is in the upper limit position, it protrudes significantly upward from the cover 14, making it easier to rotate, and when it is in the lower limit position, it fits into the recess 14a of the cover 14.

[0031] When the handle 56 moves upward, the first spline 56f of the inner cylindrical portion 56c engages with the spline 46a of the handle presser 46, allowing the handle 56, the handle presser 46, and the stem 44 to rotate together. When the handle 56 moves to the upper limit position, the second spline 56g of the inner cylindrical portion 56c disengages from the spline 16d of the handle support portion 16.

[0032] When the handle 56 moves downward, the first spline 56f of the inner cylindrical portion 56c is disengaged from the spline 46a of the handle presser 46 integrated with the stem 44, and the second spline 56g of the inner cylindrical portion 56c is engaged with the spline 16d of the handle support portion 16, preventing rotation of the handle 56. When the second spline 56g of the inner cylindrical portion 56c begins to engage with the spline 16d of the handle support portion 16, the flange 56e of the inner cylindrical portion 56c comes into contact with the flange portion 44a of the stem 44, and the stem 44 moves downward together with the handle 56.

[0033] A first rib 16b and a second rib 16c that engage with a rib 56d of the outer tubular portion 56b of the handle 56 are formed at a predetermined interval in the vertical direction on the outer periphery of the handle support portion 16 of the cover 14. When the handle 56 is pulled up to the upper limit position, the rib 56d of the handle 56 snaps into engagement with the first rib 16b of the handle support portion 16, and when the handle 56 is pushed down to the lower limit position, the rib 56d of the handle 56 snaps into engagement with the second rib 16c of the handle support portion 16. Therefore, the handle 56 that has reached the upper limit position or the lower limit position is stably held in that position unless an external force is applied.

[0034] In the housing chamber 40, a support frame 60 supporting a stepping motor 58 is disposed horizontally. The support frame 60 is attached to the main body 12 by a fixing means (not shown). The valve gear 48 meshes with a motor gear 50 attached to an output shaft 58a of the stepping motor 58, and rotates in conjunction with the output shaft 58a of the stepping motor 58. The valve gear 48 and the motor gear 50 are disposed on the upper surface of the support frame 60. The valve gear 48 is composed of a gear portion 48a having teeth formed on its outer periphery and a shaft portion 48b protruding downward from the gear portion 48a, and the gear portion 48a and the shaft portion 48b are provided with a central hole 48c penetrating in the X direction, which is the axial direction of the gear portion 48a and the shaft portion 48b. A spline 48d that engages with a spline 44d of the stem 44 is formed on the inner periphery of the gear portion 48a (see FIG. 4).

[0035] The support frame 60 is provided with an insertion hole 60a through which the feed screw 42 and the stem 44 are inserted. The upper part of the insertion hole 60a is enlarged in diameter to form a first recess 60b that supports the shaft part 48b of the valve gear 48, and the lower part of the insertion hole 60a is enlarged in diameter in stages to form a second recess 60c into which the upper end part of the valve seat body 28 is inserted. The valve gear 48 is supported so that it can rotate around the axis while its movement in the X direction, which is the axial direction, is restricted, by the shaft part 48b being inserted into the first recess 60b and the protrusion part 48e provided on the upper surface of the gear part 48a abutting against the cover 14. The support frame 60 is positioned inside the accommodation chamber 40 by the upper end part of the valve seat body 28 fitting into the second recess 60c.

[0036] The cylindrical portion 44b of the stem 44 is inserted into the central hole 48c of the valve gear 48 and the insertion hole 60a of the support frame 60. When the handle 56 is pushed down to move the stem 44 downward, the spline 44d of the stem 44 engages with the spline 48d of the valve gear 48, and the driving force of the stepping motor 58 is transmitted to the feed screw 42 via the motor gear 50, the valve gear 48, and the stem 44. On the other hand, when the handle 56 is pulled up to move the stem 44 upward, the spline 44d of the stem 44 and the spline 48d of the valve gear 48 are disengaged from each other.

[0037] A board 62 on which electronic components for driving the stepping motor 58 are mounted is disposed perpendicular to the support frame 60 in the accommodation chamber 40. A needle-shaped terminal 64 erected on the board 62 extends to the inside of a cylindrical connector portion 66 provided on the side of the main body 12. Wiring (not shown) is provided between the board 62 and the stepping motor 58, and the stepping motor 58 is driven by a remote control signal supplied from the terminal 64.

[0038] The flow rate control valve 10 according to this embodiment is configured as described above, and the cases of adjusting the valve opening degree by remote control and manual adjustment will be described below. As shown in Fig. 4, the initial state is when the handle 56 is in the upper limit position.

[0039] When the stepping motor 58 is driven by remote control to adjust the valve opening, the handle 56, which is at the upper limit position, is pushed down to the lower limit position. As shown in FIG. 5, when the handle 56 is pushed down, the first spline 56f of the inner cylindrical portion 56c of the handle 56 is disengaged from the spline 46a of the handle holder 46, and the stem 44 integrated with the handle holder 46 is released from the connected state with the handle 56. That is, the power transmission path between the handle 56 and the needle valve 34 is cut off between the handle 56 and the handle holder 46 in the middle. The reason why the stem 44 does not move down immediately when the handle 56 is pushed down is that an appropriate frictional force is acting at the portion where the upper end of the feed screw 42 is fitted into the cylindrical portion 44b of the stem 44 or the portion where the cylindrical portion 44b of the stem 44 is inserted into the central hole 48c of the valve gear 48.

[0040] Furthermore, at almost the same time that the first spline 56f of the handle 56 is disengaged from the spline 46a of the handle retainer 46, the second spline 56g of the inner cylindrical portion 56c of the handle 56 begins to engage with the spline 16d of the handle support portion 16, thereby preventing the handle 56 from rotating.

[0041] When the handle 56 is pressed down near the lowest position, the stem 44 is pressed down by the flange 56e of the handle 56, and the spline 44d of the stem 44 engages with the spline 48d of the valve gear 48 (see FIG. 1). This enables the driving force of the stepping motor 58 to be transmitted to the needle valve 34 via the motor gear 50, the valve gear 48, the stem 44, and the feed screw 42. In other words, the power transmission path between the stepping motor 58 and the needle valve 34 becomes continuous.

[0042] As described above, when the handle 56 is pushed down, the power transmission path between the handle 56 and the needle valve 34 is cut off midway and the rotation of the handle 56 is prevented, and when the handle 56 is pushed down further to the lowest position, the power transmission path between the stepping motor 58 and the needle valve 34 is continuous. In this state, the stepping motor 58 can be driven by remote control to move the needle valve 34 in the axial direction and adjust the valve opening.

[0043] Next, when manually adjusting the valve opening, the handle 56 is pulled up from the lower limit position to the upper limit position. As shown in FIG. 6, when the handle 56 is pulled up, the first spline 56f of the inner tubular portion 56c first engages with the spline 46a of the handle holder 46, and the handle 56, the handle holder 46, and the stem 44 are integrally connected in the rotational direction. This makes the power transmission path between the handle 56 and the needle valve 34 continuous. However, unless the handle 56 is pulled up to near the upper limit position, the second spline 56g of the inner tubular portion 56c does not disengage from the spline 16d of the handle support portion 16, and the handle 56 cannot be rotated at this point.

[0044] Next, when the handle 56 is raised close to the upper limit position, the handle presser 46 is pushed up by the flange 56e of the handle 56, and the spline 44d of the stem 44, which moves integrally with the handle presser 46, is disengaged from the spline 48d of the valve gear 48 (see FIG. 4). Also, the second spline 56g of the inner cylindrical portion 56c of the handle 56 is disengaged from the spline 16d of the handle support portion 16. As a result of the disengagement of the spline 44d of the stem 44 and the spline 48d of the valve gear 48, the power transmission path between the stepping motor 58 and the needle valve 34 is interrupted midway.

[0045] Therefore, by raising the handle 56 to its upper limit position, it becomes possible to manually rotate the handle 56. By rotating the handle 56, the needle valve 34 is moved in the axial direction via the handle retainer 46, the stem 44, and the feed screw 42, thereby making it possible to adjust the valve opening degree.

[0046] Even if the stepping motor 58 is driven by a remote control signal while an on-site worker is in the process of pulling up the handle 56 and before the spline 48d of the valve gear 48 and the spline 44d of the stem 44 are disengaged, and the driving force is transmitted to the handle 56 via the stem 44, the second spline 56g of the inner cylindrical portion 56c of the handle 56 is engaged with the spline 16d of the handle support portion 16, so that the handle 56 will not rotate unexpectedly and the safety of the worker holding the handle 56 is ensured.

[0047] The flow rate control valve 10 according to this embodiment is provided with a power transmission mechanism that selectively switches between the rotational operating force of the handle 56 and the driving force of the stepping motor 58 and transmits them to the needle valve 34, so that manual handle operation can be easily achieved regardless of the specifications of the stepping motor 58, and the safety of workers on site is also ensured. In addition, the above switching can be performed by the push-pull operation of moving the handle 56 in the direction of the rotation axis, providing good operability.

[0048] The flow rate regulating valve according to the present invention is not limited to the above-described embodiment, and it goes without saying that various configurations can be adopted without departing from the gist of the present invention. [Explanation of symbols]

[0049] 10...Flow rate adjusting valve 12...Main body 14...Cover 14a...Recess 16...Handle support portion 16a...Step portion 16b...First rib 16c...Second rib 16d, 44d, 46a, 48d…spline 18...Fluid passage 28...Valve seat body 34...Needle valve 36...Needle packing 42... Lead screw 44... Stem 46...Handle holder 48...Valve gear 56…Handle 56d…Rib 56f…First spline (spline) 56g…Second spline (spline) 58... Stepping motor (electric motor) 58a... Output shaft

Claims

1. A flow control valve in which a needle valve is disposed facing a fluid passage provided in a main body, the flow control valve comprising: a handle for manual rotational operation; an electric motor that can be remotely operated; and a power transmission mechanism that selectively switches between the rotational operating force of the handle and the driving force of the electric motor and transmits them to the needle valve, the switching being performed by moving the handle in the direction of a rotation axis; the handle is movable in one direction and in the other direction along a rotation axis, and when the handle is pulled to move in the one direction, the power transmission path between the handle and the needle valve becomes continuous and the power transmission path between the electric motor and the needle valve is interrupted midway, and when the handle is pushed to move in the other direction, the power transmission path between the handle and the needle valve is interrupted midway and the power transmission path between the electric motor and the needle valve becomes continuous; A flow control valve in which the handle and a handle support portion provided on the main body are formed with splines that can engage with each other, and when the handle moves from the moving end in one direction to the other direction, the splines of the handle engage with the splines of the handle support portion to prevent the handle from rotating.

2. 2. The flow rate regulating valve according to claim 1, A flow control valve comprising a cover that houses the electric motor and the power transmission mechanism together with the main body, and a recess is formed in the cover into which the handle fits when the handle moves to the end of movement in the other direction.

3. 2. The flow rate regulating valve according to claim 1, The power transmission mechanism includes a feed screw that screws into the needle valve, wherein the rotation of the needle valve around its axis is restricted, and the movement of the feed screw in the axial direction is restricted, so that when the feed screw rotates, the needle valve moves in the axial direction.

4. 4. The flow rate regulating valve according to claim 3, The power transmission mechanism includes a stem that is movable in the axial direction of the feed screw, the feed screw rotates integrally with the stem, and the rotational operating force of the handle and the driving force of the electric motor are transmitted to the needle valve via the stem and the feed screw.

5. The flow rate regulating valve according to claim 4, When the handle moves in one direction from the moving end in the other direction, splines formed on the handle engage with splines formed on a handle retainer fixed to the stem, and when the handle moves in the other direction, the stem moves in the same direction, and the splines formed on the stem engage with splines formed on a valve gear that is linked to the output shaft of the electric motor.

6. 6. The flow rate regulating valve according to claim 5, A flow control valve in which, when the stem, which is integral with the handle retainer and is moved by contact with the handle, contacts a step provided on the handle support part, the handle reaches the end of its movement in one direction, and, when the handle contacts an end of the handle support part, the handle reaches the end of its movement in the other direction.

7. 7. The flow rate regulating valve according to claim 6, A flow control valve in which, when the handle reaches the end of its movement in one direction, a rib provided on the handle snaps into engagement with a first rib provided on the handle support portion, and, when the handle reaches the end of its movement in the other direction, the rib provided on the handle snaps into engagement with a second rib provided on the handle support portion.

8. 4. The flow rate regulating valve according to claim 3, The flow control valve has a needle valve inserted inside a valve seat body fixed to the main body, and a needle packing that is in sliding contact with the valve seat body is attached to the outer periphery of the needle valve.

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