Flow Control Valve

Abstract

Provided is a flow rate control valve that prevents foreign matter from being jammed therein and that can appropriately control a flow rate.　The flow rate control valve (1) comprises: a valve body (31) in which a valve seat (31e) is provided; a deceleration part (20) that decelerates and transmits the rotation of a motor to a rotating body (26); a conversion mechanism that moves a moving body in an axial direction according to the rotational movement of the rotating body; and a valve disc (33) that moves according to the movement in the axial direction of the moving body, and moves toward or away from the valve seat. A first engagement part (26b) provided on the rotating body and a second engagement part (29) provided on the valve body move toward or away from each other according to the rotation of the rotating body. After the valve disc is seated on the valve seat, the first engagement part is brought into contact with the second engagement part, and the rotation of the rotating body is stopped.

Description

[Technical field]

[0001] The present invention relates to a flow control valve. [Background technology]

[0002] For example, a refrigeration cycle used in a room air conditioner, a car air conditioner, etc., includes a compressor, an outdoor heat exchanger, an indoor heat exchanger, an expansion valve, and a flow control valve that adjusts the flow rate of the refrigerant.

[0003] As an example of this type of flow control valve, a gear-type motorized valve is known, as shown in Patent Document 1. This gear-type motorized valve reduces the rotational force output from a stepping motor through a reduction mechanism, and then converts the reduced rotational force into an axial force using a screw mechanism and transmits it to a valve element. This causes the valve element to move away from or seat on the valve seat, thereby executing a valve opening or closing operation. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2003-232465 A Summary of the Invention [Problem to be solved by the invention]

[0005] In the gear-type electric valve shown in Patent Document 1, the rotational force of the stepping motor is decelerated by a reduction gear device, so that the pressing force exerted from the valve body to the valve seat when the valve is closed is relatively high, which has the advantage of maintaining high sealing performance when the valve is closed.

[0006] On the other hand, there is a risk that foreign objects such as metals may be mixed into the refrigerant circulating in the refrigeration cycle. If such foreign objects enter the gear-type motor-operated valve and become trapped between the valve body and the valve seat when the valve is closed, they may be pinched by a strong pressing force, resulting in so-called foreign object entrapment.

[0007] An object of the present invention is to provide a flow control valve that can suppress the ingestion of foreign matter and perform appropriate flow control. [Means for solving the problem]

[0008] In order to achieve the above object, the flow control valve according to the present invention comprises: A valve body provided with a valve seat; a speed reducer that reduces the rotation speed of the motor and transmits the reduced speed to a rotor; a conversion mechanism that moves a moving body in an axial direction in response to the rotational movement of the rotating body; a valve body that moves in response to axial movement of the movable body and moves toward and away from the valve seat, a first engagement portion disposed on the rotor and a second engagement portion disposed on the valve body are provided to approach or move away from each other in response to rotation of the rotor, After the valve body is seated on the valve seat, the first engagement portion and the second engagement portion come into contact with each other, and the rotation of the rotor is stopped. The rotor is guided so as to slide along a female threaded cylinder fixed to the valve body. And, the reduction gear unit has a planetary gear mechanism, and the rotating body is a gear body of the planetary gear mechanism, The conversion mechanism includes a male screw member that rotates together with the gear body and a female screw tube that screws into the male screw member, the male screw member is the movable body, The gear body is guided so as to slide along the outer periphery of the female threaded cylinder. It is characterized by: Effect of the Invention

[0009] According to the present invention, it is possible to provide a flow control valve that can suppress the ingestion of foreign matter and perform appropriate flow control. [Brief description of the drawings]

[0010] [Figure 1] 1 is a vertical cross-sectional view showing a flow control valve according to a first embodiment in a closed state. [Diagram 2] FIG. 2 is a plan view of a cross section taken along line AA of the flow control valve shown in FIG. [Diagram 3]FIG. 3 is a vertical cross-sectional view showing the flow control valve according to the first embodiment in an open state. [Figure 4] FIG. 4 is a plan view of a cross section similar to that of FIG. 2 of the flow control valve shown in FIG. [Diagram 5] FIG. 5 is a diagram showing a gear train used in the flow control valve of this embodiment, developed so that the axes of the gears are positioned on the same plane. [Figure 6] FIG. 6 is a cross-sectional view similar to FIG. 5, showing a gear train according to a modified example of this embodiment. [Figure 7] FIG. 7 is a vertical cross-sectional view showing a flow control valve according to the second embodiment in a closed state. [Figure 8] 8 is a plan view of a cross section taken along line BB of the flow control valve shown in FIG. [Figure 9] FIG. 9 is a vertical cross-sectional view showing the flow control valve according to the second embodiment in an open state. [Figure 10] FIG. 10 is a plan view of a cross section similar to that of FIG. 8 of the flow control valve shown in FIG. [Figure 11] FIG. 11 is a diagram showing the gear train used in the flow control valve of this embodiment, developed so that the axes of the gears are positioned on the same plane. [Figure 12] FIG. 12 is a vertical cross-sectional view showing a flow control valve according to the third embodiment in a closed state. [Figure 13] FIG. 13 is a vertical cross-sectional view showing the flow control valve according to the third embodiment in an open state. [Figure 14] FIG. 14 is an exploded view of the planetary gear mechanism. [Figure 15] FIG. 15 is a perspective view showing the bottom surface of the gear body and the top surface of the female thread cylinder. [Figure 16] FIG. 16 is a vertical cross-sectional view showing a flow control valve according to the fourth embodiment in a closed state. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A flow control valve according to an embodiment of the present invention will now be described with reference to the drawings. The flow control valve according to the present embodiment is installed in a circulation path of a refrigeration cycle device and controls the flow rate of a refrigerant flowing through the circulation path.

[0012] [First embodiment] Fig. 1 is a vertical cross-sectional view showing a closed state of a flow control valve 1 according to a first embodiment, and Fig. 2 is a plan view of a section taken along line AA of the flow control valve 1 shown in Fig. 1. Fig. 3 is a vertical cross-sectional view showing an open state of the flow control valve 1 according to the first embodiment, and Fig. 4 is a plan view of a section similar to Fig. 2 of the flow control valve shown in Fig. 3. Fig. 5 is a partially simplified view showing a gear train used in the flow control valve 1 developed so that the axes of the gears are positioned in the same plane.

[0013] (Flow control valve configuration) The flow control valve 1 has a drive section 10, a speed reducer section 20, and a valve mechanism section 30. The axis of the valve mechanism section 30 is designated as L. In addition, the motor side will be described as the upper side, and the valve body side as the lower side.

[0014] First, the drive unit 10 will be described. In the figure, the drive unit 10 has a drive unit case 11, a stator 12 attached to the inside of the drive unit case 11, a rotor 13 arranged radially inside the stator 12, and a drive shaft 14 fixed to the rotor 13. The stator 12 and the rotor 13 configure a stepping motor. Note that the drive source is not limited to a stepping motor, and a brushless motor, a brushed motor, etc. may also be used.

[0015] The drive unit case 11 is formed in a cylindrical shape with a top, and a bearing 15 is fixed to the underside of the center of the top. The bearing 15 rotatably holds the drive shaft 14. A cylindrical support tube 16 with a top is disposed below the stator 12 and rotor 13 so as to fit into the inner periphery of the drive unit case 11. The lower end of the support tube 16 abuts against the upper surface of an annular member 17 that closes the drive unit case 11, and the lower end of the drive unit case 11 and the outer periphery of the annular member 17 are fixed by caulking.

[0016] The support cylinder 16 has a hollow cylindrical portion 16a formed on the bottom surface at the center of the top portion, and a through hole (not shown). The lower end of the drive shaft 14 passes through the through hole of the support cylinder 16 and is rotatably supported by the through hole.

[0017] Next, the speed reducing portion 20 will be described. The reduction gear section 20 has a first shaft 21 and a second shaft 22, both ends of which are held by the lower surface of the top of the support tube 16 and the upper surface of the annular member 17, a drive gear 23 fixed to the lower end of the drive shaft 14 passing through the through hole of the support tube 16, a first transmission gear 24 held rotatably relative to the first shaft 21, a second transmission gear 25 held rotatably relative to the second shaft 22, a final gear 26, an externally threaded shaft 27, and an internally threaded tube 28. The final gear 26 constitutes a rotating body, and the externally threaded shaft 27 constitutes a moving body. The externally threaded shaft 27 is press-fitted and fixed to the final gear 26 to form an integral unit.

[0018] The first shaft 21 and the second shaft 22 are disposed in parallel to the drive shaft 14. As shown in Fig. 5, the first transmission gear 24 is formed by coaxially connecting a first input gear portion 24a meshing with the drive gear 23 and a first output gear portion 24b. The second transmission gear 25 is formed by coaxially connecting a second input gear portion 25a meshing with the first output gear portion 24b and a second output gear portion 25b meshing with the final gear 26. Each shaft may be made of metal, and each gear may be made of resin. The drive gear 23, the first transmission gear 24, the second transmission gear 25, and the final gear 26 form a gear train.

[0019] The number of teeth ZA of the drive gear 23 is smaller than the number of teeth ZB of the first input gear portion 24a. Moreover, the number of teeth ZC of the first output gear portion 24b is smaller than the number of teeth ZD of the second input gear portion 25a. Furthermore, the number of teeth ZE of the second output gear portion 25b is smaller than the number of teeth ZF of the final gear 26. Therefore, while the rotational force is transmitted from the drive gear 23 to the final gear 26, the speed is reduced by a reduction ratio of (ZB / ZA)×(ZD / ZC)×(ZF / ZE).

[0020] 2 and 4, the final gear 26 has an arc groove 26a on its underside so as to surround the male screw shaft 27. One end of the arc groove 26a in the circumferential direction is the end 26b, and the other end is the end 26c. The angle from the end 26b to the end 26c is a given value. Here, the end 26b constitutes a first engagement portion, and the end 26c constitutes a third engagement portion. The first engagement portion and the third engagement portion will be described later. As described above, the final gear 26 constitutes a rotating body, but the rotating body is not limited to the final gear 26. For example, any member that receives a rotational force from the rotor 13 and rotates and has at least a first engagement portion that approaches or moves away from the second engagement portion of the valve body 31 depending on the rotation can be used as the rotating body.

[0021] 1 and 2, a hole 17a is formed in the upper surface of the annular member 17, and the lower end of a pin 29 is fitted and fixed in the hole 17a. The upper end of the pin 29 is disposed so as to be located within the arc groove 26a. The pin 29 constitutes a second engagement portion and a fourth engagement portion disposed on the valve body 31. Here, "disposed on the valve body 31" includes the case where the pin 29 is directly disposed on the valve body 31, as well as the case where the pin 29 is indirectly disposed on another member fixed to the valve body 31. The second engagement portion and the fourth engagement portion will be described later.

[0022] The male threaded shaft 27 has its upper end fitted into the inner circumference 16b of the hollow cylindrical portion 16a of the support tube 16, and is disposed within the hollow cylindrical portion 16a so as to be capable of relative rotation and axial displacement. The final gear 26 is fitted and fixed at the intermediate position of the male threaded shaft 27, and a male thread 27a is formed on the outer circumference of the lower end side.

[0023] The female threaded tube 28, which is a hollow cylinder, is fitted and fixed at its reduced-diameter upper end to the inner circumference of the annular member 17, and has a through hole 28a that penetrates along the axis L. A female thread 28b that screws into the male thread 27a is formed at the lower end of the through hole 28a. Since the female threaded tube 28 is fixed to the annular member 17, when the male threaded shaft 27 rotates, the male thread 27a screws into the female thread 28b, and an axial force is applied from the female threaded tube 28. As a result, the male threaded shaft 27 is displaced in the axial direction by an amount corresponding to its own rotation angle. The male threaded shaft 27 and the female threaded tube 28 constitute a conversion mechanism.

[0024] The female threaded cylinder 28 has an enlarged diameter thin-walled cylindrical portion 28c at its lower end. A cylindrical connecting member 34 is disposed on the outer periphery of the female threaded cylinder 28. The connecting member 34 has a reduced diameter upper end portion 34a that fits onto the outer periphery of the female threaded cylinder 28, and an internal thread portion 34b on the inner periphery of the lower end.

[0025] Next, the valve mechanism 30 will be described. The valve mechanism 30 includes a valve body 31 , a valve stem 32 , and a valve element 33 .

[0026] The metallic valve body 31 is a relatively thick hollow cylinder with a reduced diameter portion 31a on the outer periphery of the upper end and an external thread portion 31b on the outer periphery below the reduced diameter portion 31a. The thin-walled cylindrical portion 28c fits onto the outer periphery of the reduced diameter portion 31a. The internal thread portion 34b of the connecting member 34 fitted onto the outer periphery of the female threaded tube 28 is screwed into the external thread portion 31b, and the connecting member 34 is screwed in, so that the lower surface of the reduced diameter upper end portion 34a abuts and engages with the upper end step portion of the thin-walled cylindrical portion 28c. This allows the female threaded tube 28 to be connected and fixed to the valve body 31.

[0027] A spacer 35 is arranged between the lower surface of the female threaded tube 28 on the inner circumference of the thin-walled cylindrical portion 28c and the upper end of the valve body 31, so that the distance between the valve body 31 and the female threaded tube 28 when connected and fixed can be adjusted.

[0028] A first pipe 51 constituting a first flow passage is connected to an opening 31c formed on the outer periphery near the lower end of the valve body 31 so as to be perpendicular to the axis L. The axis of the first pipe 51 is designated by O.

[0029] An opening formed coaxially with the axis L at the lower end of the valve body 31 constitutes an orifice 31d. An upper end of the orifice 31d constitutes a valve seat 31e. A second pipe 52 is connected to the valve body 31 so as to communicate with the orifice 31d.

[0030] A valve shaft 32 is disposed inside the valve body 31. The valve shaft 32 is composed of a small diameter portion 32a, a large diameter portion 32b, a flange portion 32c, and a small diameter protrusion portion 32d, which are coaxially connected to each other. A ball retaining portion 32e, which is separate from the valve shaft 32, is attached to the upper end of the small diameter portion 32a, which faces the lower end of the male screw shaft 27. A metal ball 37 is disposed between a recess in the center of the lower end of the male screw shaft 27 and a recess in the center of the upper end of the ball retaining portion 32e.

[0031] An annular plate 36 is fixed by crimping to the inner periphery of the upper end of the valve body 31. A metal bellows 38 connects the lower surface of the annular plate 36 to the outer periphery of the upper end of the large diameter portion 32b of the valve shaft 32, surrounding the small diameter portion 32a of the valve shaft 32. Therefore, when the flow control valve 1 is in use, inside the valve body 31, the outside of the bellows 38 comes into contact with the refrigerant, but the inside of the bellows 38 comes into contact with the atmosphere. The outside of the bellows 38 inside the valve body 31 constitutes the valve chamber C.

[0032] A cylindrical valve body 33 with a bottom is disposed below the valve shaft 32. The valve body 33 is formed by connecting a large cylindrical portion 33a at the upper end side, which is slidable against the inner circumference of the valve body 31, a small cylindrical portion 33b at the lower end side, and a bottom portion 33c. A tapered surface 33d that is symmetrical with respect to the axis L is formed on the lower surface side of the bottom portion 33c. The upper end of the large cylindrical portion 33a is fixed to the outer periphery of an annular slide plate 40 by crimping. The slide plate 40 is fitted to the large diameter portion 32b of the valve shaft 32 so as to be slidable along the axis L direction, but does not move further below the valve shaft 32 by abutting against the flange portion 32c. The valve shaft 32 and the valve body 33 can be relatively displaced by a predetermined distance in the axial direction.

[0033] A coil spring 39, which is a biasing member, is disposed on the inner peripheral side of the small cylindrical portion 33b of the valve body 33. The upper end of the coil spring 39 abuts against the lower end of the valve shaft 32 around the small diameter protrusion 32d, and the lower end of the coil spring 39 abuts against the upper surface of the bottom portion 33c of the valve body 33. Therefore, the valve body 33 is constantly biased downward relative to the valve shaft 32 by the coil spring 39. The male threaded shaft 27 may be formed integrally with the valve shaft 32 and the valve body 33.

[0034] (Flow control valve operation) The operation of the flow control valve 1 according to this embodiment will be described. The first pipe 51 and the second pipe 52 are connected to a refrigeration cycle, with the first pipe 51 being the inlet pipe and the second pipe 52 being the outlet pipe.

[0035] (When valve is closed) From the open state, power is supplied to the drive unit 10 from an external power source in response to a control signal, and when the drive shaft 14 rotates in one direction, the rotation is reduced through the gear train of the reduction unit 20 and transmitted to the male screw shaft 27. The rotational motion transmitted to the male screw shaft 27 is converted to axial motion through the conversion mechanism of the reduction unit 20, whereby the male screw shaft 27 is displaced downward together with the final gear 26 (the screw shaft 27 moves axially downward in response to the rotation of the final gear 26). Even if the final gear 26 is displaced in the axial direction, it does not come out of mesh with the second transmission gear 25.

[0036] When the male screw shaft 27 is displaced downward, the valve shaft 32 moves downward by being pushed via the ball 37. When the valve shaft 32 moves downward, the bellows 38 expands, and the valve body 33 moves downward while being pushed by the coil spring 39, and the tapered surface 33d seats on the valve seat 31e. At this time, the coil spring 39 exerts a cushioning effect that reduces the impact when seated.

[0037] As the valve stem 32 further rotates, it descends and the coil spring 39 is compressed, pressing the tapered surface 33d against the valve seat 31e with a predetermined biasing force. At this time, the slide plate 40 slides along the outer periphery of the large diameter portion 32b of the valve stem 32, allowing relative displacement of the valve stem 32 and the valve body 33 against the biasing force of the coil spring 39. As a result, a predetermined preload is applied and the valve is kept closed, blocking the flow of refrigerant from the first pipe 51 through the valve chest C to the second pipe 52. This state is shown in Figure 1.

[0038] During this time, the fluid pressure in the valve chamber C acts on the outer surface of the bellows 38. If the fluid pressure is equal to or greater than a predetermined value, the bellows 38 will contract and the valve body 33 will move in the opening direction together with the valve shaft 32.

[0039] Incidentally, the rotational force output from the drive unit 10 is decelerated by the speed reducer 20, and therefore the force that moves the male screw shaft 27 and the valve shaft 32 in the axial direction also becomes strong. Therefore, if further rotational force is applied from the drive unit 10 when the valve shaft 32 bottoms out on the valve body 33, the pressing force generated between the tapered surface 33d and the valve seat 31e becomes excessive.

[0040] In this embodiment, a structure is provided to prevent the pressing force generated between the tapered surface 33d and the valve seat 31e from becoming excessive. Specifically, when the final gear 26 rotates together with the male screw shaft 27, the pin 29 moves relatively along the arc groove 26a, and the pin 29 and the end 26b approach each other. Furthermore, when the male screw shaft 27 rotates a predetermined angle after the tapered surface 33d is seated on the valve seat 31e, the pin 29 (second engagement portion) abuts against the end 26b (first engagement portion) of the arc groove 26a, so that the final gear 26 is prevented from rotating any further, and the valve shaft (valve body) does not move down any further. Such a state is shown in FIG. 2. That is, the pin 29 (second engagement portion) and the end 26b (first engagement portion) each function as a lower limit stopper for the valve body.

[0041] This prevents the male threaded shaft 27 and the valve shaft 32 from descending, so that the pressing force applied to the valve body 33 against the valve shaft 32 is only the biasing force of the coil spring 39, and an excessive increase in the pressing force generated between the tapered surface 33d and the valve seat 31e can be avoided. At this time, even if a foreign object is caught between the tapered surface 33d and the valve seat 31e, no indentation is generated because the pressing force is relatively low, and if the foreign object falls off the next time the valve is opened, good sealing between the tapered surface 33d and the valve seat 31e can be ensured.

[0042] (When the valve is open) On the other hand, when the drive shaft 14 rotates in the reverse direction due to power supply from an external power source in response to a control signal with reverse characteristics, the rotation is reduced through the gear train of the reduction unit 20 and transmitted to the male threaded shaft 27. The rotational motion transmitted to the male threaded shaft 27 is converted into axial motion through the conversion mechanism of the reduction unit 20, whereby the male threaded shaft 27 is displaced upward together with the final gear 26.

[0043] When the male screw shaft 27 is displaced upward, the force pressing the valve shaft 32 in the valve closing direction disappears, and the bellows 38, which receives refrigerant pressure in the valve chamber C, contracts while the valve shaft 32 also rises. When the valve shaft 32 rises, the slide plate 40 engages with the flange 32c of the valve shaft 32, and then the valve body 33 also rises together with the valve shaft 32, so that the tapered surface 33d moves away from the valve seat 31e. This state is shown in Figure 3.

[0044] At this time, the refrigerant that has entered the valve chamber C from the first pipe 51 passes through the gap between the tapered surface 33d and the valve seat 31e, and flows out into the second pipe 52 via the orifice 31d. Since the gap between the tapered surface 33d and the valve seat 31e changes depending on the rotation angle of the drive shaft 14, the amount of refrigerant flowing from the first pipe 51 to the second pipe 52 can be adjusted by adjusting the rotation angle of the drive shaft 14.

[0045] Furthermore, according to this embodiment, even if the drive shaft 14 rotates too far in the reverse direction due to, for example, a step-out phenomenon, the pin 29 (fourth engagement portion) abuts against the end 26c (third engagement portion) on the opposite side of the arc groove 26a, preventing the final gear 26 from rotating any further, and the valve stem (valve body) will not rise any further. This state is shown in Figure 4. That is, the pin 29 (fourth engagement portion) and the end 26b (third engagement portion) each function as an upper limit stopper for the valve body.

[0046] (Modification) Fig. 6 is a cross-sectional view similar to Fig. 5, showing a gear train according to a modified example of this embodiment. The speed reducer 20A of this modified example also has a first shaft 21, a second shaft 22, a drive gear 23, a first transmission gear 24, a second transmission gear 25, a final gear 26A, and a male threaded shaft 27. Components common to the above-mentioned embodiment are given the same reference numerals and will not be described again.

[0047] In this modified example, unlike the above-described embodiment, no arc groove is provided on the underside of the final gear 26A, and instead, a protrusion 26Aa is formed on the underside at a position away from the axis L. The protrusion 26Aa constitutes a first engagement portion.

[0048] As in the above-described embodiment, the final gear 26A moves up and down together with the male screw shaft 27 in response to rotation, and the projection 26Aa descends in a spiral motion around the axis L when the valve element 33 moves from the open state to the closed state. Therefore, by adjusting the height H of the projection 26Aa in advance, the projection 26Aa passes over the top of the pin 29 (second engagement portion) (misses the ball) during the first rotation, and the projection 26Aa (first engagement portion) can be brought into contact with the pin 29 only after the second rotation (see FIG. 5), preventing further rotation of the output gear. That is, the pin 29 (second engagement portion) and the projection 26Aa (first engagement portion) each function as a lower limit stopper.

[0049] According to this modification, it is possible to select an appropriate reduction ratio of the reduction gear section 20A because there is a greater degree of freedom in selecting the timing for contacting the projection 26Aa with the pin 29. Also, according to this modification, by not providing a groove, the final gear 26A can be made thinner, thereby enabling the weight of the flow control valve to be reduced.

[0050] In order to prevent the tip end faces of the protrusion 26Aa and the pin 29 from abutting against each other, it is preferable that the tip end faces of the protrusion 26Aa and the pin 29 are formed so as to have an inclined surface parallel to the inclination of the threads of the male screw (female screw) rather than a flat surface.

[0051] [Second embodiment] Fig. 7 is a vertical cross-sectional view showing a closed state of a flow control valve 1B according to a second embodiment, and Fig. 8 is a plan view of a section taken along line BB of the flow control valve 1B shown in Fig. 7. Fig. 9 is a vertical cross-sectional view showing an open state of the flow control valve 1B according to the second embodiment, and Fig. 10 is a plan view of a section similar to Fig. 8 of the flow control valve shown in Fig. 9. Fig. 11 is a partially simplified view showing a gear train used in the flow control valve 1B developed so that the axes of the gears are positioned in the same plane.

[0052] (Flow control valve configuration) The flow control valve 1B has a drive section 10B, a speed reducer section 20B, and a valve mechanism section 30. Here again, the axis of the valve mechanism section 30 is designated as L. In addition, the following description will be given with the motor side as the upper side and the valve body side as the lower side.

[0053] The driving unit 10B of this embodiment includes a support tube 16B. A fixed shaft 16Ba is formed coaxially with the axis L on the bottom surface of the top of the support tube 16B. The annular member 17B does not have a pin implanted therein. Instead, a pin 29B is implanted downward at a position away from the axis L on the bottom surface of the support tube 16B.

[0054] The reduction gear unit 20B includes a first shaft 21 and an idle shaft 22B, both ends of which are held by the lower surface of the top of the support tube 16B and the upper surface of the annular member 17B, a drive gear 23 fixed to the lower end of the drive shaft 14, a first transmission gear 24 rotatably held relative to the first shaft 21, a final gear 25B rotatably held by the fixed shaft 16Ba and coaxially connected to the male screw shaft 27B, and an idle gear 26B coaxially connected to the idle shaft 22B and meshing with the final gear 25B. The final gear 25B constitutes a rotating body. The same reference numerals are used for the same components as those in the above-mentioned embodiment, and duplicated explanations will be omitted.

[0055] A raised portion 26Ba is formed on the upper surface of the idle gear 26B. The raised portion 26Ba is formed in a narrow sector shape when viewed in the direction of the axis L as shown in Figures 8 and 10. One side surface of the raised portion 26Ba facing each other in the circumferential direction is an end surface 26Bb, and the other side surface is an end surface 26Bc. The angle from the end surface 26Bb to the end surface 26Bc is a given value.

[0056] The first transmission gear 24 is formed by coaxially connecting a first input gear portion 24a meshing with the drive gear 23 and a first output gear portion 24b. The final gear 25B is formed by coaxially connecting an input gear portion 25Ba meshing with the first output gear portion 24b and an output gear portion 25Bb meshing with the idle gear 26B.

[0057] In the flow control valve 1B, when the male screw shaft 27B rotates a predetermined angle after the valve body 33 is seated, the end surface 26Bb (first engagement portion) of the raised portion 26Ba of the idle gear 26B comes into contact with the pin 2. Further rotation of the final gear 25B is prevented because the pin 29 (second engagement portion) and the end face 26Bb (first engagement portion) each function as a lower limit stopper for the valve body.

[0058] In contrast, when the male screw shaft 27B rotates in the reverse direction while the valve is open, the end face 26Bc of the raised portion 26Ba (third engagement portion) of the idle gear 26B abuts against the pin 29 (fourth engagement portion), preventing further reverse rotation of the final gear 25B. This state is shown in Figure 10. That is, the pin 29 (fourth engagement portion) and the end face 26Bb (third engagement portion) each function as an upper limit stopper for the valve body.

[0059] In this embodiment, the number of teeth ZA of the drive gear 23 is less than the number of teeth ZB of the first input gear portion 24a. Also, the number of teeth ZG of the input gear portion 25Ba of the final gear 25B is less than the number of teeth ZC of the first output gear portion 24b. Therefore, while the rotational force is transmitted from the drive gear 23 to the final gear 25B, the speed is reduced by a reduction ratio (ZB / ZA)×(ZC / ZG). Meanwhile, the number of teeth ZH of the output gear portion 25Bb of the final gear 25B is less than the number of teeth ZI of the idle gear 26B, so the rotation of the idle gear 26B is reduced by a reduction ratio (ZI / ZH) relative to the final gear 25B.

[0060] According to this embodiment, since the rotation angle of the idle gear 26B is increased relative to the rotation angle of the final gear 25B, the timing at which the pin 29 abuts against the end face 26Bb can be set with higher accuracy. Alternatively, the lift amount of the valve body 33 relative to the rotation angle of the drive gear 23 can be increased without changing the timing at which the pin 29 abuts against the end face 26Bb. This reduces the pressure loss when the valve is fully open, making it possible to reduce the orifice diameter, and is expected to reduce the differential pressure load.

[0061] [Third embodiment] Fig. 12 is a vertical cross-sectional view showing a flow control valve 1C according to the third embodiment in a closed state, and Fig. 13 is a vertical cross-sectional view showing a flow control valve 1C according to the third embodiment in an open state, but the stator is omitted here. Fig. 14 is a view showing the planetary gear mechanism in an exploded state. Fig. 15 is a perspective view showing the bottom surface of the gear body 125 and the top surface of the female thread tube 128.

[0062] (Flow control valve configuration) The flow control valve 1C includes a drive unit 110, a planetary gear type speed reduction mechanism (hereinafter, abbreviated as "speed reduction unit") 120 that performs gear speed reduction by receiving the rotational force from the drive unit 110, and a valve mechanism unit 130. The axis of the flow control valve 1C is designated as L. In addition, the motor side will be described as the upper side, and the valve body side as the lower side.

[0063] In the figure, a can 111 arranged radially inside a stator (not shown) is an airtight container whose lower end is fixed to a valve body 131 via an annular receiving member 112, and has a thin-walled, cylindrical shape with a top. The drive unit 110 has a permanent magnet type rotor assembly 113 that is rotationally driven by a stator (not shown). The rotor assembly 113 is supported rotatably inside the can 111. The stator and rotor assembly 113 form a stepping motor, which is an example of an electric motor.

[0064] As shown in Fig. 14, the reduction gear unit 120 includes a sun gear 121 that is integral with the rotor assembly 113, a plurality of (three in this example) axially long planetary gears 123 that are rotatably supported by a carrier 122 formed by molding plastic, for example, and that mesh with the sun gear 121, a ring gear 124 that is arranged concentrically with the sun gear and meshes with a portion (upper portion) of each planetary gear 123, and a gear body 125 that includes an output gear portion 125a that has internal teeth on its inner circumference that are slightly different in number from the number of teeth of the ring gear 124 (i.e., in a shifted relationship with the ring gear 124). The sun gear 121, the carrier 122, the ring gear 124, and the gear body 125 are preferably formed from PPS (polyphenylene sulfide resin). The gear body 125 constitutes a rotating body.

[0065] As is clear from FIG. 14, each planetary gear 123 meshes with the ring gear 124 and at the same time, a portion (lower portion) of the planetary gear 123 meshes with an output gear portion 125a of the gear body 125.

[0066] The rotor assembly 113 is made of a plastic material (PPS in this case) containing a magnetic material, and is integrally formed into a cylindrical shape with a top, with a cylinder 126 as a peripheral wall and a sun gear member 127 disposed in the center. The rotor assembly 113 is rotatably supported inside the can 111 by a shaft 114 (FIGS. 12 and 13) that passes through the sun gear member 127 in the axial direction.

[0067] 14, the sun gear 121 is formed on the outer periphery of a cylinder that is set in the center of a sun gear member 127. The ring gear 124 is a ring-shaped gear made by molding, for example, plastic.

[0068] According to this configuration, when the sun gear 121 rotates on its axis due to the rotation input of the electric motor, the planetary gear 123, which meshes with the sun gear 121 and the ring gear 124, revolves around the sun gear 121 while rotating on its axis. Since the planetary gear 123 meshes with the gear body 125 that is in a shifted relationship with the ring gear 124, this rotation of the planetary gear 123 causes the gear body 125 to rotate at a relatively high reduction ratio, for example, of about 50:1 with respect to the ring gear 124, depending on the degree of shift (difference in the number of teeth). A planetary gear mechanism in which the planetary gear 123 meshes with the ring gear 124 that is in a shifted relationship with the output gear portion 125a, is called a paradox planetary gear mechanism.

[0069] The carrier 122 has a lower disk 122b formed by three pillars 122a arranged in parallel on the outer periphery of the upper surface, an annular plate 122c, and a cylindrical carrier shaft 122d extending downward from the center of the lower disk 122b, and the lower disk 122b and the plate 122c are fixed in parallel via the pillars 122a. A fitting hole 122e into which the lower end of the shaft 114 is rotatably fitted is formed coaxially on the upper end side of the carrier shaft 122d, and an engagement hole 122f is formed coaxially on the lower end side thereof. The engagement hole 122f has a non-circular shape, such as a D-shape, in a cross section perpendicular to the axis L.

[0070] Between circumferentially adjacent column portions 122a, both ends of a planetary gear 123 made of a zinc alloy are rotatably held by the lower disk 122b and the plate 122c, thereby allowing the planetary gear 123 to rotate relative to the carrier 122.

[0071] 12 and 13, a female threaded cylinder 128 is disposed below the carrier 122. The female threaded cylinder 128 is fixedly connected to the upper end of a valve body 131 via an annular plate 132.

[0072] The female threaded cylinder 128 is made of resin with excellent sliding properties such as PTFE (polytetrafluoroethylene), and has a metal annular plate 132 fixed to the vicinity of its upper end by insert molding or the like. The female threaded cylinder 128 has a cylindrical opening 128a formed in the center of the upper end, a female threaded portion 128b communicating with the opening 128a, and a thin-walled cylindrical portion 128c on the lower end side. The carrier shaft portion 122d is fitted into the opening 128a so as to be rotatable relative to the opening 128a.

[0073] In Fig. 15, a protrusion 125c is formed on the lower surface of the gear body 125 at a position spaced apart from the axis. On the other hand, a locking portion 128e is formed on the upper surface of the female thread tube 128 below the thin-walled cylindrical portion 128c. The locking portion 128e has a guide portion 128f in the shape of a semi-cylindrical surface extending over a predetermined angle, a step portion 128g formed at one end in the circumferential direction of the guide portion 128f, and a step portion 128h formed at the other end. The protrusion 125c constitutes the first engagement portion and the third engagement portion, the step portion 128g constitutes the second engagement portion, and the step portion 128h constitutes the fourth engagement portion.

[0074] In addition, the gear body 125 is guided to the outer periphery of the thin-walled cylindrical portion 128c, so that the rotation axis of the gear body 125 is fixed and the rotation of each gear is stabilized. Also, by providing the protrusion 125c in the same direction as and close to the guide arranged below the output gear portion 125a, even when the protrusion 125c abuts against the step portion 128g, a load is unlikely to be generated in a direction intersecting the rotation axis of the gear, so that wear of the gear can be reduced. The first to fourth engagement portions will be described later.

[0075] Furthermore, in this embodiment, the protrusion 125c is formed on the lower surface of the gear body 125, and the locking portion 128e (step portion 128g) is formed on the upper surface of the female screw tube 128, but it is of course possible to form the protrusion 125c on the upper surface of the gear body 125 and the locking portion 128e (step portion 128g) on ​​the lower surface of the ring gear 124. In this case, by guiding the outer periphery of the gear body 125 and the inner periphery of the gear case 141, it is difficult for a load to be generated in a direction intersecting the rotation axis of the gear, and wear of the gear can be reduced. Of course, the protrusion 125c may be formed on the side surface of the gear body 125, and the locking portion 128e may be arranged accordingly.

[0076] When the reduced-diameter thin-walled cylindrical portion 128c of the female threaded tube 128 is fitted into the bottom opening 125b of the gear body 125 to assemble the gear body 125 and the female threaded tube 128, the upper surface of the locking portion 128e comes into contact with the lower surface of the gear body 125. In this state, the gear body 125 and the female threaded tube 128 are capable of rotating relative to each other, whereby the protrusion 125c moves relatively along the outer periphery of the guide portion 128f.

[0077] 12 and 13, the male screw member 129 inserted into the female screw tube 128 comprises an engaging portion 129a, a male screw portion 129b, and a disk portion 129c connected together. The engaging portion 129a has a non-circular cross section perpendicular to the axis L, similar to the engaging hole 122f, and while engaged with the engaging hole 122f, it can move relative to the engaging hole 122f in the axial direction, but rotates integrally with the engaging hole 122f in the rotational direction. The male screw portion 129b screws into the female screw portion 128b. The male screw member 129 constitutes a moving body.

[0078] Here, the annular plate 132 fixed to the female threaded tube 128 is joined to the valve body 131 by welding or the like, so that when the male threaded member 129 rotates, the male threaded portion 129b screws onto the female thread 128b. As a result, an axial force is applied from the female threaded tube 128, so that the male threaded member 129 is displaced in the axial direction by an amount according to the rotation angle. Since the female threaded tube 128 is made of PTFE, no lubricant such as grease is required. The male threaded member 129 and the female threaded tube 128 constitute a conversion mechanism.

[0079] The disk portion 129c is disposed in the thin-walled cylindrical portion 128c of the female threaded cylinder 128. A communication hole 128d is formed in the peripheral wall of the thin-walled cylindrical portion 128c.

[0080] Next, the valve mechanism 130 will be described. The metallic valve body 131 is a hollow cylinder with a relatively thick wall, and as described above, the lower end of the can 111 is fixed via the annular receiving member 112, and the outer periphery of the upper end of the valve body 131 and the outer periphery of the ring gear 124 are connected by the gear case 141 which is a thin cylindrical member. In the valve body 131, a communication hole 131a is formed in the peripheral wall between the gear case 141 and the receiving member 112. The interior of the valve body 131 constitutes the valve chamber C.

[0081] A first pipe 51 constituting a first flow passage is connected to an opening 131c formed on the outer periphery near the lower end of the valve body 131 so as to be perpendicular to the axis L. The axis of the first pipe 51 is designated by O.

[0082] An opening formed coaxially with the axis L at the lower end of the valve body 131 constitutes an orifice 131d. An upper end of the orifice 131d constitutes a valve seat 131e. The second pipe 52 is connected to the valve body 131 so as to communicate with the orifice 131d.

[0083] A sleeve member 133 having a cylindrical shape with a bottom is disposed below the male screw member 129. The sleeve member 133 is formed by connecting a cylindrical portion 133a, which fits and slides on the inner periphery of the thin-walled cylindrical portion 128c, and a bottom portion 133c. A communication hole 133b is formed in the peripheral wall of the cylindrical portion 133a. The upper end of the cylindrical portion 133a is fixed to the outer periphery of the disk portion 129c of the male screw member 129 by crimping, and the sleeve member 133 and the male screw member 129 move together. The bottom portion 133c has a circular opening 133d in the center.

[0084] The needle member 134 is formed by connecting a flange portion 134a and a body portion 134b having a smaller diameter than the flange portion 134a. A spacer 135 is disposed between the flange portion 134a and a bottom portion 133c of the sleeve member 133.

[0085] When the flange portion 134a is disposed within the sleeve member 133 and the body portion 134b is fitted into the circular opening 133d, the lower end side of the body portion 134b protrudes from the sleeve member 133, but because the flange portion 134a gets caught on the edge of the circular opening 133d, the needle member 134 does not fall off from the sleeve member 133.

[0086] A cylindrical holder 136 is disposed above flange portion 134a of needle member 134. Holder 136 is formed by connecting a circular flange portion 136a and a cylindrical portion 136b.

[0087] A coil spring 139 is disposed outside the cylindrical portion 136b with its lower end abutting against the upper surface of the circular flange portion 136a. The upper end of the coil spring 139, which is a biasing member, abuts against the lower surface of the disk portion 129c. Therefore, the needle member 134 is constantly biased downward against the male screw member 129 via the holder 136 by the coil spring 139.

[0088] An annular valve body 137 is attached by press fitting or the like to the outer periphery of the body portion 134b protruding downward from the sleeve member 133. The outer periphery of the valve body 137 is conical in shape with the diameter decreasing downward. The lower end of the needle member 134 may also be conical in shape. When the needle member 134 is pressed downward, a predetermined gap is formed between the lower surface of the sleeve member 133 and the upper surface of the valve body 137, and the sleeve member 133 and the needle member 134 can be relatively displaced in the axial direction by this gap. This gap can be adjusted by changing the thickness of the spacer 135.

[0089] (Flow control valve operation) The operation of the flow control valve 1C according to this embodiment will be described. The first pipe 51 and the second pipe 52 are connected to a refrigeration cycle, with the first pipe 51 being the inlet pipe and the second pipe 52 being the outlet pipe.

[0090] (When valve is closed) When power is supplied from an external power source in response to a control signal from an open valve state, a stator (not shown) generates a magnetic force. The rotor assembly 113 is rotated by an angle corresponding to the magnetic force, generating a rotational force in a predetermined direction. The rotational force is transmitted to the sun gear 121, reduced in speed through the reduction gear unit 120, and transmitted to the output gear unit 125a, causing the gear body 125 to rotate around the axis L.

[0091] The male screw member 129 rotates in accordance with the rotation of the gear body 125. The rotational motion of the male screw member 129 is converted into axial motion via the conversion mechanism, whereby the male screw member 129 is displaced downward relative to the gear body 125. When the male screw member 129 is displaced downward, the sleeve member 133, the holder 136, the needle member 134, and the valve body 137 are also displaced downward. At this time, the protrusion 125c also moves relatively along the outer periphery of the guide portion 128f and approaches the step portion 128g.

[0092] After the outer circumferential surface of the valve body 137 seats on the valve seat 131e, the sleeve member 133 moves downward relative to the needle member 134, which is fixed in position, and the coil spring 139 is further compressed. At this time, the coil spring 139 exerts a cushioning effect that reduces the impact caused by the seating. The male thread member 129 further descends, pressing the valve body 137 against the valve seat 131e with a predetermined biasing force, maintaining the valve closed state, and blocking the flow of refrigerant from the first pipe 51 through the valve chamber C to the second pipe 52. This state is shown in Figure 11.

[0093] In this embodiment, before the gap between the lower surface of the sleeve member 133 and the upper surface of the valve body 137 becomes zero, the protrusion 125c (first engagement portion) abuts against the step 128g (second engagement portion) of the guide portion 128f, preventing further rotation and lowering of the male screw member 129. That is, the protrusion 125c (first engagement portion) and the step 128g (second engagement portion) each function as a lower limit stopper for the valve body.

[0094] As a result, the pressing force applied to the valve body 137 is only the biasing force of the coil spring 39, and an excessive increase in the pressing force generated between the valve body 137 and the valve seat 131e can be avoided. At this time, even if a foreign object is caught between the valve body 137 and the valve seat 131e, no indentation is caused because the pressing force is relatively low, and if the foreign object falls off the next time the valve is opened, good sealing between the valve body 137 and the valve seat 131e can be ensured.

[0095] According to this embodiment, the gear body 125 and the female threaded tube 128 do not move relative to each other in the axial direction, so that the protrusion 125c and the step portion 128g abut at the same position, thereby ensuring a sufficient abutment area and thereby increasing durability.

[0096] (When the valve is open) On the other hand, when power is supplied from an external power source in response to a control signal with reverse characteristics, the rotor assembly 113 is driven to rotate and generates a rotational force in the reverse direction. This rotational force is transmitted to the sun gear 121, reduced in speed through the reduction gear unit 120, and transmitted to the output gear unit 125a, causing the gear body 125 to rotate in the reverse direction around the axis L.

[0097] The male screw member 129 rotates in accordance with the rotation of the gear body 125. The rotational motion of the male screw member 129 is converted into axial motion via the conversion mechanism, whereby the male screw member 129 is displaced upward relative to the gear body 125. When the male screw member 129 is displaced upward, the sleeve member 133, the holder 136, the needle member 134, and the valve body 137 are also displaced upward. At this time, the protrusion 125c also moves relatively along the outer periphery of the guide portion 128f.

[0098] When the outer circumferential surface of the valve element 137 separates from the valve seat 131e, the refrigerant that has entered the valve chamber C from the first pipe 51 passes through the gap between the valve element 137 and the valve seat 131e and flows out into the second pipe 52 via the orifice 131d. The gap between the valve element 137 and the valve seat 131e changes according to the rotation angle of the sun gear 121, so the amount of refrigerant flowing from the first pipe 51 to the second pipe 52 can be adjusted by adjusting the rotation angle of the sun gear 121. This state is shown in FIG.

[0099] At this time, the refrigerant flowing into the valve chamber C enters the thin-walled cylindrical portion 128c through the communication hole 128d, enters the sleeve member 133 through the communication hole 133b, and enters the can 111 through the communication hole 131a, thereby eliminating the pressure difference between various portions within the flow control valve 1C that may hinder operation.

[0100] Furthermore, according to this embodiment, even if the sun gear 121 rotates too far in the reverse direction due to, for example, a step-out phenomenon, the protrusion 125c (third engagement portion) abuts against the step 128h (fourth engagement portion) of the guide portion 128f, preventing further rotation and elevation of the male screw member 129. That is, the protrusion 125c (third engagement portion) and the step 128h (fourth engagement portion) each function as an upper limit stopper for the valve body.

[0101] [Fourth embodiment] 16 is a vertical cross-sectional view showing a flow control valve 1D according to a fourth embodiment in a closed state, but similarly omitting the stator. This embodiment differs from the third embodiment mainly in the shapes of the gear body 125D and the female threaded tube 128D, and in that the carrier 122D and the shaft portion 122Dd are separated. Configurations common to the above-mentioned embodiments are given the same reference numerals and will not be described again.

[0102] The gear body 125D, which is a rotating body, has an annular portion 125De that protrudes upward from the upper end periphery of the central bottom opening 125Db. A disk-shaped carrier 122D is slidably disposed on the upper surface of the annular portion 125De. The female threaded tube 128D does not have a thin cylindrical portion, and its upper end surface faces the lower surface of the gear body 125D.

[0103] The reduced-diameter upper end 122Dh of the shaft portion 122Dd is press-fitted into the inner periphery of the bottom opening 125Db of the gear body 125D, and the lower end side of the shaft portion 122Dd is slidably fitted into the opening 128Da of the female threaded tube 128D. The upper end surface of the shaft portion 122Dd is disposed opposite the lower surface of the carrier 122D. An engagement portion 129a of the male thread member 129 is fitted into the engagement hole 122Df of the shaft portion 122Dd. The lower end of the shaft 114 passes through the central opening of the carrier 122D and is fitted into the fitting hole 122De of the shaft portion 122Dd so as to be rotatable relative to the carrier 122D.

[0104] According to this embodiment, instead of the carrier 122D and the shaft portion 122Dd rotating relative to each other, the gear body 125D and the shaft portion 122Dd rotate integrally. Therefore, the male screw member 129 also rotates at the same time through the engagement between the engagement hole 122Df and the engagement portion 129a. As a result, the female screw 128Db and the male screw portion 129b screw relative to each other, and the valve body 137 is displaced in the direction of the axis L.

[0105] Although the gear body 125D is the gear that is most decelerated by the reduction gear section 120, in this configuration the rotational angle through which the gear body 125D can rotate is small (for example, less than 360 degrees), so in this embodiment, the thread pitch of the female thread 128Db and the male thread section 129b is made relatively large to ensure the required lift amount of the valve body 137.

[0106] As a means for ensuring the lift amount, in addition to increasing the thread pitch, a multiple start thread (for example, a double start thread) may be used for the female thread 128Db and the male thread portion 129b. When the thread diameter is small, simply increasing the pitch does not provide sufficient rigidity, so the use of such a multiple start thread is effective.

[0107] In this embodiment, too, a protrusion 125Dc is formed on the underside of the gear body 125D at a position spaced from the axis. As in the above-described embodiment, by providing the protrusion 125Dc at a position close to the upper end of the shaft portion 122Dd, even when the protrusion 125Dc abuts against a step portion of the female threaded tube 128D, a load is unlikely to be generated in a direction intersecting the rotation axis of the gear, so that wear of the gear can be reduced. The protrusion 125Dc constitutes the first and third engagement portions, and the step portion of the guide portion 128Df of the female threaded tube 128D constitutes the second and fourth engagement portions.

[0108] In addition, this embodiment has a feature that the rotation angle of the male screw member 129 is smaller than that of the above-mentioned embodiment. Therefore, instead of providing a protrusion on the gear body 125D, a protrusion is provided on the male screw member 129, and a convex portion facing the protrusion is provided on the female screw tube 128D or the valve body 131, and the two are arranged at positions where they can come into contact with each other, thereby suppressing over-rotation of the male screw member 129. In this case, the male screw member 129 constitutes the rotating body and the moving body. [Explanation of symbols]

[0109] 1, 1B, 1C, 1D Flow control valve 10, 10B Drive unit 20, 20B reduction section 26a Circular groove of final gear 26Ba Idle gear protrusion 29 pin 30, 130 Valve mechanism 31 Valve body 32 Valve stem 33, 137 Valve body 120 Reduction section (planetary gear mechanism) 125c, 125Dc Gear body protrusion 128g Female threaded cylinder step

Claims

1. A valve body provided with a valve seat; a speed reducer that reduces the rotation speed of the motor and transmits the reduced speed to a rotor; a conversion mechanism that moves a moving body in an axial direction in response to the rotational movement of the rotating body; a valve body that moves in response to axial movement of the movable body and moves toward and away from the valve seat, a first engaging portion disposed on the rotating body and a second engaging portion disposed on the valve body are provided so as to approach or move away from each other in response to rotation of the rotating body, After the valve body is seated on the valve seat, the first engagement portion and the second engagement portion come into contact with each other, and the rotation of the rotor is stopped. The rotor is guided so as to slide along a female threaded cylinder fixed to the valve body, the reduction gear unit has a planetary gear mechanism, and the rotating body is a gear body of the planetary gear mechanism, The conversion mechanism includes a male screw member that rotates together with the gear body and a female screw tube that screws into the male screw member, the male screw member is the movable body, The gear body is guided so as to slide along the outer periphery of the female threaded cylinder. A flow control valve characterized by:

2. the planetary gear mechanism includes a sun gear integral with a rotor of the motor, a carrier for rotatably supporting a planetary gear meshing with the sun gear, a ring gear concentric with the sun gear and fixed to the valve body side to mesh with the planetary gear, and a gear body including an output gear portion having internal teeth formed on its inner circumference, the number of teeth of which differs from that of the ring gear; The carrier has a carrier shaft portion that is slidably fitted into an inner peripheral portion of the female threaded cylinder.

2. The flow control valve according to claim 1.

3. a biasing member for biasing the valve body toward the valve seat with respect to the movable body; 2. The flow control valve according to claim 1.

4. a third engaging portion disposed on the rotor and a fourth engaging portion disposed on the valve body, After the valve body is separated from the valve seat by a predetermined distance, the third engagement portion and the fourth engagement portion come into contact with each other.

2. The flow control valve according to claim 1.

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