JP2000291817A - Flow control device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a flow control device capable of controlling the flow rate with high accuracy though any highly accurate parts design is unnecessary for a fixing structure of a regulating valve to a rotary shaft. SOLUTION: This flow control device 1 comprises a cylindrical body part 2, a regulating valve 25 to regulate the flow rate of a fluid by the insertion position into an opening 28, and a motor to drive the regulating valve 25. A rotor part 33 of the motor is driven in the forward direction to move the rotor part and a rotary shaft 34 straight in the direction toward the opening 28, while the rotor part is driven in the reverse direction to move the rotor part and the rotary shaft straight in the direction away from the opening. A cylindrical holding member 24 is fixed to a tip side of the rotary shaft, an open end of the holding member 24 is bent inwardly to cause the regulating valve, and the regulating valve 25 is held on the holding member 24 by the bent portion of the holding member 24 and an energizing means 26 to energize the regulating valve to an open end side.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in a flow rate control device for adjusting a flow rate by driving a regulating valve constituted by a needle valve or the like by linearly reciprocating a rotating shaft.

[0002]

2. Description of the Related Art Conventionally, as a device for controlling a flow rate of a refrigerant in a refrigerator or an air conditioner, there is a device using an electromagnetic valve or a device using a needle valve.

However, a flow control device using a solenoid valve is
Generally, one of the settings of opening and closing is performed.
It is not suitable for fine adjustment of the flow rate. Also, one of the problems is that the opening / closing operation has a loud noise, and it is necessary to keep the solenoid valve energized to maintain that state in either the open or closed state. There is also a problem in terms of power consumption.

On the other hand, a flow control device using a needle valve controls a flow rate of a fluid by using, for example, a stepping motor as a drive source and changing the rotational force of the stepping motor into the thrust of the needle valve. Compared to the solenoid valve, there are fewer problems with operating noise.
Fine adjustment of the flow rate is also possible.

[0005]

However, in the flow control device using the needle valve, the center axis in the moving direction of the needle valve and the flow path in which the needle valve is inserted are used in order to perform the control with high accuracy. The positional relationship of the center axis of the (opening) becomes delicate. Therefore, there is also a problem that a highly accurate design technique and empirical know-how at the time of assembly are required.

Further, when the motor used in this type of fluid control device is rotating in a direction to close the valve, an excessive load is applied to the motor even though the valve is closed. In such a case, a friction mechanism for absorbing the force is usually provided. In other words, even if it is a needle valve or another valve, it changes the torque of the motor into the force to move the valve and controls the valve to close the channel by inserting a part of the valve into the channel. In, even if the valve is sealed in the flow path, if a force is further applied in the direction of pushing the valve, the valve will be in a locked state, when opening the valve, when the valve is moved, It may not be possible to return to the original state.

In order to prevent such inconvenience, a friction mechanism is provided to prevent the valve from reaching a position where the valve is closed and to apply any further force to move the valve. In the event that a more excessive load is to be applied in spite of the state, the rotor is allowed to idle and the valve is not driven any more.

Further, as described above, when the rotor portion rotates forward or backward, the rotor portion and the rotating shaft attached to the rotor portion linearly reciprocate, thereby enabling an actuator-like function. When the rotor rotates in the direction to close the valve (forward rotation) and then rotates the rotor in the reverse direction to open the valve, the rotor rotates by a predetermined number of revolutions. After the reverse rotation, it is necessary to stop the rotation in a state where the rotor returns to the predetermined position.

That is, with the rotation of the rotor, the rotor and the rotary shaft move linearly in the direction to close the valve, and after the operation of closing the valve is performed, the rotor is reversely rotated to open the valve. Then, the rotor itself returns linearly in the direction of opening the valve. At that time, it is necessary to surely stop the movement of the rotor at a predetermined position. For example, when a stepping motor is used as the motor, when the rotor is rotated in the reverse direction from a state in which the valve is closed, the number of steps for driving the rotor to rotate in the reverse direction is often predetermined, and the rotor is It is possible to reliably stop the movement of the rotor unit at a position rotated by the determined number of rotations.

However, the electrical control of the number of steps is of poor reliability. That is, when the rotor moves for some reason, the stop position fluctuates, and the control becomes unstable. In addition, there is a danger that the screw provided on the rotating shaft of the rotor unit locks with the guide screw due to the reverse rotation.

In order to eliminate the instability and the lock between the screws, it is necessary to provide a stopper mechanism. However, the conventional stopper mechanism has a complicated structure and an impact noise generated when the stopper comes into contact with the stopper. However, there is a problem that the sound appears as harsh sound.

As described above, the motor for performing this type of control requires, in addition to the above-described friction mechanism, a stopper mechanism for regulating the movement of the rotor portion in controlling the opening direction of the valve. This stopper mechanism also has various problems, such as a large number of parts, a complicated structure, and a poor assembly workability. In particular, in a device that requires strong miniaturization, it is necessary to provide not only a friction mechanism but also a stopper mechanism in a limited small space, so that the structure is simple and the workability at the time of assembly is good, and In addition, it is necessary to provide a stopper mechanism that performs a reliable stopper function.

In view of the above, the present invention provides a flow control device capable of performing high-precision flow control, in spite of not requiring high-precision component design, particularly for a structure for fixing the adjustment valve and the rotating shaft. The purpose is to: In addition, the present invention has a simple structure, a small size, and a reliable stopper function.
It is an object of the present invention to provide a flow control device using a motor capable of minimizing harsh impact noise generated when a stopper mechanism operates.

[0014]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention is directed to a method for controlling the flow rate of a fluid, which is connected to an inflow pipe for inflow of a fluid and an outflow pipe for outflow of the fluid. A cylindrical main body having an opening, an adjustment valve movable in a state in which a distal end side is inserted into the opening, and adjusting a flow rate of fluid according to the insertion position, and a motor for driving the adjustment valve The motor has a rotor portion holding a rotating shaft and a stator portion arranged to face the rotor portion, and the rotor portion rotates in a predetermined direction (positive direction). (Referred to as "rotation"), the rotor portion and the rotating shaft move linearly in a direction toward the opening, and the rotor portion rotates in a direction opposite to a predetermined direction (referred to as "reverse rotation"). From the opening Conversion means for converting the rotational movement of the rotor into linear movement, and a holding member fixed to the tip end side of the rotating shaft and holding the adjustment valve, and The holding member is formed of a tubular member that accommodates the adjustment valve inside such that one end is opened and the distal end side of the adjustment valve projects from the open end, and the opening end is bent inward to caulk the adjustment valve. In addition, a biasing means for biasing the adjustment valve toward the open end is provided, and the adjustment valve is sandwiched between the biasing means and the bent portion of the open end.

Another aspect of the present invention is the flow control device according to the above-mentioned invention, wherein the conversion means has a male screw formed at a position that does not deform when the holding member is swaged, and the inner surface of the opening or the adjusting valve Is provided with a tapered surface on one of the outer circumferences, and the other is a straight surface.

According to another aspect of the present invention, in the flow control device according to each of the above aspects, the converting means forms a male screw on the rotating shaft and a female screw on the main body side, and further comprises a male screw on the rotating shaft. Is formed, and a cylindrical portion is formed on the body portion side so as to be in sliding contact with the straight portion.

Still another aspect of the present invention is directed to a cylindrical main body having an opening for adjusting a flow rate of a fluid, which is connected to an inflow pipe for inflowing a fluid and an outflow pipe for outflow of the fluid. A flow control device having a regulating valve movable in a state in which the distal end side is inserted into the opening and adjusting a flow rate of the fluid according to the insertion position, and a motor for driving the regulating valve; Has a rotor portion holding a rotating shaft, a bottomed rotor storage case for storing the rotor portion, and a stator portion disposed outside the rotor storage case so as to face the rotor portion, By rotating the rotor in a predetermined direction (referred to as forward rotation), the rotor and the rotation shaft can be moved linearly in a direction away from the inner bottom surface of the rotor storage case, and the rotor is rotated in a direction opposite to the predetermined direction. By rotating the rotor portion (reverse rotation), the rotor portion and the rotating shaft can linearly move in a direction toward the inner bottom surface of the rotor storage case, and the rotor portion has an end surface facing the inner bottom surface of the rotor storage case. Protrusions are provided, and a plate-like rotor restricting member having elasticity is provided on the inner bottom surface side of the rotor storage case.
The rear end side is fixed to the inner bottom surface of the rotor storage case, and the front end side is provided within the rotation locus of the projection and at a predetermined height from the inner bottom surface of the rotor storage case, and the rotor portion rotates forward. In this case, the protrusion advances along the rotor restricting member so as to be able to push down the rotor restricting member toward the tip of the rotor restricting member. When the rotor rotates in the reverse direction, when the rotor returns to a predetermined position, the protrusion Is configured to abut the rotor regulating member to prevent rotation, and furthermore, a conversion means for converting the rotational motion of the rotor portion into a linear motion, and a regulating means fixed to the tip end of the rotating shaft and holding the adjusting valve. And a holding member, and the holding member is formed of a cylindrical member that accommodates the adjustment valve therein such that one end thereof is opened and the distal end side of the adjustment valve protrudes from the open end.
The regulating valve is caulked by bending the open end inward, and is provided with urging means for urging the regulating valve toward the open end, and the regulating valve is sandwiched between the urging means and the bent portion of the open end.

According to the flow control device of the present invention, an adjustment valve constituted by a needle valve or the like is held at the tip of a rotating shaft of a motor by a "caulking" force and a "biasing" force by a spring or the like. The member is fixed, and the adjustment valve is moved in the flow path by the driving force of the motor. For this reason, the regulating valve faces the flow path (the opening formed in the main body) with some play, and strictly faces the control valve, so that it is not necessary to set the dimensions so precisely at the time of design. it can.

Further, the converting means for converting the rotational force of the rotor portion into a propulsive force in a linear direction is constituted by a male screw and a female screw, and is provided at a position where the male screw is not deformed by caulking (for example, separately from the holding member). In this case, the screws are screwed together smoothly and accurately.

In addition to the screwing of the screws, the rotational force is converted to propulsive force by sliding the portion of the rotary shaft where the screw is not formed and the cylindrical portion on the main body side. It is not necessary to make the dimensions of the screws so strict.

In the flow control device according to another aspect of the present invention, when the rotor section is rotated in the forward direction and the rotor section is linearly moved to a certain position, and then the rotor section is rotated in the reverse direction, a predetermined value is set. Since the rotor has a rotor restricting member that restricts reverse rotation of the rotor at a position or more, even if the rotor continues to rotate reversely, when the rotor returns to a predetermined position, the movement of the rotor can be reliably restricted. Thus, the rotor portion can be reliably stopped at a predetermined position.

The rotor restricting member can be realized with only two simple parts, the protrusion provided on the rotor portion side and the rotor restricting member provided on the rotor storage case side, and can perform reliable restriction. Further, when the rotor portion rotates forward, no impulsive sound is generated between the two, and noise can be suppressed as much as possible.

[0023]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a flow control device according to the present invention will be described below with reference to FIGS.

As shown in FIG. 1, the flow control device 1 can be roughly divided into its external configuration.
And a motor (a stepping motor is used in this embodiment, which is attached to the rear end side of the main body 2 and serves as a drive source for driving a needle valve (described later in detail) 25 as an adjustment valve. A stepping motor 3), an inflow pipe 4 attached to the distal end side of the main body 2 for inflow of a fluid, and an outflow pipe 5 for outflow of the fluid.

The stepping motor 3 includes a stator section 32 around which a coil 31 is wound, a rotor section 33 disposed inside the stator section 32 to face the same, and a rotating shaft provided in the center axis direction of the rotor section 33. A rotating shaft 34 rotatably supported by the support hole 33a, a free end at the other end supported by the rotor portion 33, and a rotating shaft 34 inserted through an inner hole of the rotating shaft 34; And a coil spring 35 that is held by the initial tightening force.

In this state, the power supply unit 36 supplies the coil 3
By supplying power to the motor 1, the rotor unit 33 rotates. Note that the coil spring 35 constitutes a part of the friction mechanism, and the coil spring 35 is hereinafter referred to as a friction spring 35. This friction mechanism will be described later. The stator section 32 around which the coil 31 is wound is housed in a stator housing body 38, and the stator housing body 38 can be detachably attached to the main body 2 by a holder 40 described later. Note that the stator portion 32 is
Are integrated with the pole teeth and the like of the stator portion 32 by resin, and the coil 31 is sealed.

In this embodiment, the main body 2 is made of cylindrical brass, and has a stepping motor 3 at its rear end.
The bearing 21 that rotatably supports the rotating shaft 34 is fixed in a state where it is press-fitted inside. At the rear end of the main body 2, there is provided a flange-shaped plate 22 joined to the main body 2 by silver brazing in a hydrogen reduction furnace (the joint portion is indicated by W). , A bottomed rotor storage case 23 that stores the rotor section 33 of the stepping motor 3 is fixed. Note that the above-described stator portion 32 is arranged outside the rotor storage case 23.

The flange-shaped plate 22 and the rotor housing case 23 are formed of a material called SUS (suspension), and these are hereinafter collectively referred to as a rotor housing.
The rotor storage case 23 has
Rotor regulation that regulates movement of the rotor part 33 (movement in the direction of the center axis of the rotating shaft 34, in this case, in particular, movement when the rotor part 33 moves toward the inner fixed surface side of the rotor storage case 23). A member 50 is provided.

The rotor restricting member 50 is formed of an elastic plate-like member. When the rotor 33 moves toward the inner bottom surface of the rotor housing case 23 while rotating, the rotor restricting member 50 is provided at the lower end of the rotor 33. The movement of the protrusion 33 b is regulated by the contact of the protrusion 33 b with the rotor regulating member 50. The protrusion 33b and the rotor restricting member 50 are collectively referred to as a rotor restricting portion, and the rotor restricting portion will be described later in detail.

The rotating shaft 34 of the stepping motor 3
Is rotatably supported by the bearing 21 of the main body 2. The rotating shaft 34 has a small-diameter portion 34b on which a male screw is formed, and a large-diameter portion 34c which is a straight portion without a male screw. On the other hand, the rotary shaft support through hole 21a of the bearing 21 provided in the main body 2
Has a small-diameter portion 21b in which a female screw is formed, and a large-diameter portion 21c which is a simple cylindrical portion in which no female screw is formed. The rotor 33 rotates while the male screw of the rotary shaft 34 and the female screw of the rotary shaft support through-hole 21a are screwed together. At this time, the straight portion of the rotary shaft 34 is simply a cylindrical portion in the rotary shaft support through-hole 21a. By sliding on
The rotary motion of the rotor unit 33 is surely converted into a linear motion. That is, the above-described configuration is a conversion unit for converting the rotational motion into the linear motion.

The portion forming the male screw is the rotating shaft 3
A carriage 2 serving as a holding member fixed to the front end of the carriage 4
4 (described later in detail), and the carriage 24
A female screw may be formed on the inner peripheral surface of the main body 2 facing the above. However, in the present embodiment, as described later, since the open end portion of the carriage 24 is bent inward and the needle valve 25 is caulked and fixed, when the needle valve 25 is caulked and fixed to the carriage 24, There is a risk that the threads will break. The above configuration is to avoid such danger,
It is formed on the rotating shaft 34 of a separate member which does not have an effect of a change in shape or the like even when the caulking is fixed.

Further, in the flow control device 1 according to the present embodiment, the conversion means does not depend only on the screwing of the screws as described above.
Since the sliding portion between the straight portion and the cylindrical portion is also used, it is not necessary to make the precision of the male screw of the rotary shaft 34 and the female screw of the main body 2 side so strict. However, instead of such a configuration, the converting means may be merely screwing of the screw during rotation of the rotor.

With this configuration, when the rotor section 33 rotates, the rotor section 33 and its rotating shaft 34 are
Along the center axis direction of 4, the body moves linearly in the axial direction while rotating inside the main body 2. Here, the rotation direction of the rotor unit 33 that advances the rotation shaft 34 in the insertion direction of the main body 2 (the end direction of the main body 2) is referred to as forward rotation. Therefore, when the rotation of the rotor section 33 is reversed (reverse rotation), the rotor section 33 and its rotating shaft 34 move toward the rear end side of the main body 2. When moving to the rear end side, the position of the rotor portion 33 is stopped at an appropriate position with respect to the stator portion 32 by the function of the rotor restricting portion described above.

A carriage 24 formed of a tubular member as a holding member for holding the needle valve 25 as an adjusting valve is attached to the tip of the rotating shaft 34. The carriage 24 moves in the main body 2 together with the rotating shaft 34 in accordance with the forward / reverse rotation of the rotor 33. One end of the carriage 24 is opened, and a needle valve 25 is housed and held inside so that the distal end projects from the open end. Therefore, the needle valve 25 moves integrally with the rotation shaft 34 and the carriage 24.

As shown in FIG. 2, the needle valve 25 has a substantially frustoconical base 25a having an inclined surface 25b.
And a needle-shaped valve portion 2 fixed to the distal end side of the base portion 25a.
5c, a shaft 25d fixed to the rear end side of the base 25a,
It is composed of And the tip side of the valve part 25c is
It is inserted into an opening (fluid outflow passage 28 described later) for adjusting the flow rate of the fluid formed in the main body 2 and is movable in this state. The opening on the side of the main body 2 is formed as a straight hole having the same inner diameter at any position. On the other hand, as shown in FIG. 3, the valve portion 25c of the needle valve 25 is formed so that the outer diameter becomes smaller toward the distal end, and the outer peripheral surface of the valve portion 25c has a slope of about 7 °. It has become.

For this reason, the needle valve 25 has a valve portion 25c.
The gap with the opening changes according to the insertion position. That is, when the rotor part 33 moves to the inner bottom surface side of the rotor storage case 23 and the needle valve 25 moves so as to retreat with respect to the opening, the gap increases and the flow rate of the fluid increases. Conversely, when the needle valve 25 moves so as to enter the opening, the gap becomes smaller and the flow rate of the fluid decreases. In the flow control device 1 of the present embodiment, the flow rate of the fluid is adjusted by adjusting the gap between the valve portion 25c of the needle valve 25 and the opening as described above.

In the present embodiment, the flow rate of the fluid is adjusted by moving forward / backward with the tapered needle valve 25 inserted into the thus formed opening. However, conversely, the inner surface of the opening may have a tapered surface, and the needle valve 25 may have a straight outer diameter. Further, both may be tapered surfaces, and the taper angle may be made larger on the needle valve 25 side.

Here, a method of holding the needle valve 25 of the carriage 24 will be described. The open end of the cylindrical carriage 24 is bent inward to fix the needle valve 25 by caulking. That is, a slope 25b is formed in the base 25a of the needle valve 25, and the bent portion at the open end comes into contact with the slope 25b. In addition, between the needle valve 25 in the carriage 24 and the above-described rotating shaft 34, there is provided an urging means for urging the needle valve 25 to the open end side. A coil-shaped pressure spring 2 serving as a motor lock preventing means by further driving the stepping motor 3 in the fitted state.
6 are interposed. For this reason, the needle valve 25 is held by the carriage 24 by being sandwiched between the bent portion of the open end of the carriage 24 (the portion bent for caulking and fixing) and the pressurizing spring 26, and the needle valve 25 Even if the stepping motor 3 reaches the innermost portion and is further driven, the locked state is not established.

That is, in the present embodiment, the pressing spring 26 contracts when the stepping motor 3 is further driven while the needle valve 25 is pressed against the opening. Then, during the contraction, the driving force of the stepping motor 3 is not transmitted to the needle valve 25, and the motor lock is avoided. In the present embodiment, the pressing spring 26 is further contracted by the further rotation of the stepping motor 3, and the leading end of the rotating shaft 34 that has advanced into the carriage 24 is the shaft 25 of the needle valve 25.
d, so as to hit the rear end. After the collision, the locked state of the stepping motor 3 is avoided by the operation of a friction mechanism described later.

In the present embodiment, with the above-described configuration, when the needle valve 25 is operated to close the opening, the needle valve 25 is once brought into contact with the opening to completely close the opening. From this state, the stepping motor 3 can be overstepped, and the origin can be found in the operation control of the needle valve 25 using this overstep.

In the present embodiment, as described above, the pressing spring 26 is contracted at the time of operating the needle valve 25 in the closing direction, and the rear end of the shaft 25d of the needle valve 25 and the rotating shaft 34 are rotated. After the contact with the tip, a friction mechanism described later is operated.
6 may be made of a tougher material that is harder to shrink, and the shaft 25 and the rotating shaft 34 may not be in contact with each other. In that case,
The pressurizing spring 26 slightly contracts due to the operation of the needle valve 25 in the closing direction, and at the moment when the contraction is slightly contracted, the friction mechanism described later starts to operate.

An inflow pipe 4 is attached to the side surface near the tip of the main body 2, and an outflow pipe 5 is attached to the tip portion. After entering the main body 2, the liquid exits to the outflow pipe 5 through a fluid outflow passage 28 formed by a small-diameter opening provided at a tip portion of the main body 2. In addition,
The inflow pipe 4 and the outflow pipe 5 are joined to the main body 2 by silver brazing in a hydrogen reduction furnace. Each of the silver brazed portions is indicated by the symbol Y.

The flow rate of the refrigerant flowing into the main body 2 through the inflow pipe 4 and flowing through the fluid outflow path 28 to the outflow pipe 5 is changed by the movement of the carriage 24 so that the valve portion 25 c of the needle valve 25 It is controlled by moving in the outflow channel 28.

That is, the valve 25c of the needle valve 25 held by the carriage 24 can be moved into the fluid outflow passage 28 provided on the distal end surface of the main body 2 in a state where it is inserted. The flow rate of the refrigerant is adjusted depending on the position of the section. Note that the inner diameter of the fluid outflow passage 28 is set to be the same as or slightly smaller than the portion of the valve portion 25c having the largest diameter. Therefore, the needle valve 2
5 can be reliably turned off (completely closed) by pushing it deeper into the interior.

The bearing portion 21 is provided with a wear powder receiving groove 21f having a V-shaped cross section on the outer surface thereof along the circumferential direction, and has one end face side to the other end face side. The two communication passages 21g, 21g penetrating the shaft are provided in parallel with the rotation shaft support through hole 21a. The wear powder receiving groove 21f is bounded by the wear powder receiving groove 21f.
The outer diameter on the front end side (the front end side in the press-fitting direction into the main body portion 2) is on the rear end side (rotor portion 33) with respect to the wear powder receiving groove 21f.
Side) is slightly smaller than the outside diameter.

The bearing portion 21 needs to be mounted in a state where the internal space of the main body 2 is completely shut off from the rotor portion 33 side. When it is attached to the main body 2, it is press-fitted into the main body 2 so as to be knocked. At this time, the leading portion (the entrance portion of the abrasion powder receiving groove 21f) of the side surface on the side of the rotor portion 33 having a slightly larger outer diameter is press-fitted while shaving the inner surface of the main body portion 2, and the abrasion that occurs at that time The powder is received in the wear powder receiving groove 21f.

That is, the rotating shaft 34 is screwed into the bearing 21, and the end of the rotating shaft 34 is provided with the carriage 24. Is press-fitted into the main body 2 in a state where it is already attached. If abrasion powder is generated at that time, the abrasion powder is left inside the main body 2. A wear powder receiving groove 21f is provided as an escape place for wear powder.

Also, as shown in FIG.
By contacting the tip end surface of the bearing 21, the bearing 21
A convex stepped portion 2b for regulating (positioning) the insertion amount of is provided in the circumferential direction of the inner peripheral surface inside thereof. In the main body 2 in this embodiment, the inner diameter at the front end side is smaller than the inner diameter at the rear end side from the convex stepped portion 2b. The inner diameter of the rear end side of the convex step 2b is
Outer diameter of bearing portion 21 on rotor portion 33 side (wear powder receiving groove 2
The outer diameter is almost the same as (the outer diameter slightly larger than the outer diameter 1), and is pressed into the main body 2 when the bearing 21 is knocked.

When the bearing 21 is completely pressed into the main body 2, the front end surface of the bearing 21 contacts the convex step 2 b of the main body 2, so that the two are in close contact with each other. As a result, even if the abrasion powder spills out of the abrasion powder receiving groove 21f, the abrasion powder does not enter the main body 2. Note that this may not be a step, for example,
A convex portion may be formed on the inner peripheral surface of the main body 2 in the circumferential direction.

The communication passages 21g, 21g are provided for draining oil such as ester oil which has entered the rotor housing case 23, and penetrate from one end surface side of the bearing portion 21 to the other end surface side. Because it is provided in
By setting the main body 2 below the rotor housing, oil such as ester oil that has entered the rotor housing 23 can be reliably extracted.

The communication passages 21g, 21g can be used not only for draining oil contained in the rotor storage case 23 but also as an introduction passage for filling the main body 2 with a refrigerant such as Freon gas. As described above, when the bearing 21 is attached to the main body 2 or when the fluorocarbon gas is charged, the rotating shaft 34 has already been rotated.
Is performed in a state where the rotor unit 33 is not mounted on the rotating shaft 34. The operation of attaching the rotor section 33 to the rotating shaft 34 can be performed very easily, but the attaching operation will be described in the following description of the friction mechanism.

The friction mechanism will be described below.

The rotor part 33 is made of a synthetic resin cylindrical member 3.
31 and a magnet 332 mounted around it. A rotation shaft support hole 33a into which the rotation shaft 34 is removably inserted is provided at the center of the cylindrical member 331. The rotation shaft support hole 33a has a rotation shaft A large diameter portion having an inner diameter larger than the support hole 33a is formed. The large-diameter portion is provided with the first large-diameter hole 33.
3 and a second large-diameter hole 334 larger than the first large-diameter hole 333 formed between the first large-diameter hole 333 and the end of the rotation support hole 33a. . A slit (not shown) is formed in the side wall of the first large-diameter hole 333 and the second large-diameter hole 334 so as to pass straight from the second large-diameter hole 334 to the first large-diameter hole 333. Have been.

On the other hand, a friction spring 35 as a part of a friction mechanism is wound around the rotating shaft 34. One end of the friction spring 35 projects in a direction perpendicular to the tangent to the circumference of the friction spring 35 (referred to as a first projection 35a), and the other end of the friction spring 35
5 protrudes in the tangential direction (referred to as a second protruding portion = not shown). The second protrusion is bent slightly downward (on the side of the first protrusion 35a).

When the friction spring 35 is viewed from above with the second protruding portion side facing upward, the first protruding portion 35a is wound clockwise (clockwise) with the second protruding portion as a base point. Has been reached.

The inner diameter of the friction spring 35 is smaller than the outer diameter of the rotating shaft 34.
Is inserted from the second protruding portion side of the friction spring 35 so as to expand the diameter of the friction spring 35 so that the friction spring 35 is wound around the rotation shaft 34. Then, in a normal state, the rotation shaft 34 and the friction spring 35 are integrated with each other by an intended tightening force originally held by the friction spring 35. The tightening force of the friction spring 35 on the rotating shaft 34 is smaller than the torque of the stepping motor 3 (the torque of the rotor 33).

Further, on the side of the second projecting portion of the friction spring 35, an E-ring 37 fixed to the rotation shaft 34 restricts the movement of the friction spring 35 toward the tip of the rotation shaft 34.

When the rotating shaft 34 around which the friction spring 35 is wound is inserted into the through hole 33a of the cylindrical member 331 of the rotor 33, the first projection 35a of the friction spring 35 is inserted into the above-mentioned slit. The rotating shaft 34 is inserted into the through hole 33a in such a manner as to enter. As a result, the first protrusion 35a of the friction spring 35
The slit is used as a guide to advance to the end of the first large-diameter hole 333, where further insertion of the rotary shaft 34 is restricted. Further, the second protruding portion is a cylindrical member 3 of the rotor portion 33.
The first large-diameter hole 334 can slide freely on the terminal surface without being fixed to the base 31.

Note that the depth (= radial length) of the slit groove provided in the cylindrical member 331 of the rotor section 33 is set to a depth that can hold the first protrusion 35a from the tip to the root. This is because, when transmitting the rotational force of the rotor section 33 to the friction spring 35, the first protrusion 35a receives the rotational force of the rotor section 33 as a whole, so that the torque is reliably transmitted. This is for improving the durability of the 35.

The width of the groove of the slit is substantially the same as the thickness of the first protrusion 35a (the thickness of the member forming the friction spring 35), and the first protrusion 35a is inserted into the slit. In this case, there is no play in the rotation direction of the rotor section 33. This is the first if
Is inserted into the slit in a state of backlash, with the rotation of the rotor unit 33,
This is because there is a possibility that noise due to rattling may occur, and this is to prevent it.

Further, the second protruding portion, which is the end opposite to the first protruding portion 35a of the friction spring 35, is free to move as described above. Although it is not necessary to provide the second projecting portion, if the end of the friction spring 35 is left as it is, the end of the friction spring 35 comes into contact with the E-ring 37 described above, and the frictional torque is reduced. In order to prevent such a situation, a normal friction operation may not be performed. To prevent this, the end of the friction spring 35 is slightly protruded, and is slightly bent downward.

The friction mechanism has such a structure, and the rotating shaft 34 and the rotor section 33 are engaged by the friction mechanism. In a state where the rotating shaft 34 and the rotor portion 33 are engaged (at this time, all components to be stored in the main body 2 such as the carriage 24 are attached), the rotor storage case 23 described above is mounted on the rotor portion. The cover 33 is joined to the flange plate 22 attached to the main body 2 by ultrasonic welding or the like.

Next, the above-described rotor restricting portion will be described.

As described above, the rotor restricting portion is constituted by the rotor restricting member 50 provided on the inner bottom surface of the rotor storage case 23 and the protrusion 33b provided on the rotor portion 33 side. As shown in FIG. 4, the rotor restricting member 50 is formed of a thin metal plate having elasticity, and has a substantially circular plate body (hereinafter, referred to as a circular plate) 5.
0a, and a corner piece 50 formed so as to be curved from the circular plate portion 50a in the outer circumferential direction so as to make a quarter turn around the circular plate portion 50a concentrically with the circular plate portion 50a.
b.

The angular contact piece 50b is formed at the base (circular plate body 50a) of the angular contact piece 50b arranged on the back side in FIG.
The line connecting the center point of the circular plate body part 50a and the center point of the circular plate body part 50a and the line connecting the tip side 50d and the center point of the circular plate body part 50a are configured to be orthogonal to each other. The tip side 50d of the angular contact piece 50b has an inclination of an angle α with respect to the horizontal plane (the circular plate portion 50a).

The rotor restricting member 50 thus configured
Sets the center position of the circular plate body 50a to the rotor housing case 2.
3 is mounted on the rotor storage case 23 by performing spot welding in accordance with the center position of the inner bottom surface. In this manner, the center of the circular plate body 50a and the center of the rotor storage case 23 are matched and the two are joined together because the circular plate body 50a on the inner bottom surface of the rotor storage case 23 is used.
The reason for this is that the welding position can be easily determined, and that welding in a narrow space such as the rotor storage case 23 is facilitated.

On the other hand, the rotor portion 33 is provided with a projection 33b at the lower end of a cylindrical member 331 made of synthetic resin. As described above, when the protrusion 33b contacts the rotor regulating member 50, further rotation of the rotor portion 33 is regulated, whereby the linear movement of the rotor portion 33 (the inner bottom surface of the rotor storage case 23) is performed. Direction) is regulated. That is, when the rotor portion 33 moves toward the inner bottom surface of the rotor storage case 23, the protrusion 33b
Abuts on the tip side 50d of the angular contact piece 50b described above, whereby further movement is restricted.

As shown in FIG. 4, the tip 33e of the projection 33b on the rotor section 33 side is a horizontal surface (rotor regulating member 5).
It has an inclination of an angle α with respect to the circular plate portion 50a). That is, the tip side 50d of the aforementioned angular contact piece 50b
Has the same angle of inclination. And this projection 33
The positional relationship between b and the angular contact piece 50b is such that the tip side 50d of the angular contact piece 50b is located within the rotation locus of the projection 33b when the rotor 33 rotates. In this embodiment, since the angular contact piece 50b is formed so as to draw an arc from the circular plate body 50a, the arc becomes an arc along the rotation locus of the projection 33.

With this configuration, the rotor section 33 rotates to a certain position due to the forward rotation of the rotor section 33, and the rotor section 33 rotates in the reverse direction while the rotor section 33 rotates to a certain position. Even if it moves in the direction of the bottom and further reversely rotates from the position where it originally stopped, the tip 33 of the protrusion 33 b provided on the rotor portion 33 will soon come.
e comes into contact with the tip side 50d of the angular contact piece 50b.

As described above, the tip 33e of the projection 33b provided on the rotor portion 33 is connected to the tip side 50 of the angular contact piece 50b.
When it comes into contact with e, further movement of the rotor portion 33 is restricted.

From this state, the rotor 33
When moving in the direction away from the inner bottom surface of the rotor storage case 23 while rotating forward, the tip 33e of the projection 33b advances while pressing the rectangular contact 50b downward while contacting the rectangular contact 50b. You can move smoothly without resistance.

The description of the rotor restricting portion will be ended here for the first time, and the following description will be given. It should be noted that the timing for restricting the movement of the rotor portion 33 and the tip 33e
The contact relationship and the like when the abutment with the tip side 50d of the angular contact piece 50b will be described later in the description of the overall operation of the flow control device.

A stator 32 on which a coil 31 is wound is mounted on the outer periphery of the side surface of the rotor housing. The stator section 32 is attached to the main body section 2 in a state where the stator section 32 is housed in the stator housing body 38. When the stator housing 38 is attached to the main body 2, the starter housing 38 is detachably held on the main body 2 by a holder 40 having elasticity.
A stepped portion 38 a is formed in the stator housing 38 so that a locking claw 40 c provided at the tip of the holder 40 can be caught.

The holder 40 is held in such a state that the outer periphery of the main body 2 is tightened by the elastic force of the main body 2. At this time, the projections (not shown) are in a state of biting into the main body 2, so that they do not move in the circumferential direction, and the step 2 provided on the main body 2.
The movement of the body 2 in the axial direction, that is, in the direction of the front end and the direction of the rear end is regulated by a, so that a reliable holding state can be obtained. The main body 2 is provided with the holder 40.
A step portion 2a for preventing displacement is formed to prevent sliding in the axial direction along the outer periphery when attached to the outer periphery.

With the holder 40 attached to the main body 2 in this way, the stator housing body 38 in which the stator section 32 is stored is mounted on the main body 2. At this time, the stator housing 38 is slid toward the main body 2 so that the rotor housing case 23 already joined to the main body 2 is inserted into the central space of the stator housing 38.

As a result, the locking claw 40c of the holder 40 falls into the step 38a provided on the stator housing 38 by its elastic force, and the stator housing 38 is held by the main body 2. When removing the stator housing 38 from the main body 2, the stator housing 38 can be removed by strongly pulling the stator housing 38 away from the main body 2.

As described above, since the stator housing 38 can be attached to and detached from the main body 2 with a single touch, the maintenance of the stator 32, the coil 31 and the power supply 36 connected to them can be performed during maintenance. It will be useful. Note that the stator section 32 and the rotor section 33 are
When the carriage 24 moves forward, and the moment when the thickest portion of the needle valve 25 contacts the fluid outflow passage 28, the rotating force of the rotor portion 33 can be maximized at the moment.
And the center of each magnetic pole of the magnet 332 of the rotor section 33 coincides with each other at the time of contact.

Next, the control of the flow rate in the fluid flow rate control device 1 configured as described above will be described.

First, the needle valve 25 in the carriage 24
Is not in contact with the fluid outflow passage 28 of the main body 2 (a state where there is a gap with the fluid flow passage 28).
Then, the fluid flowing in the inflow pipe 4 flows into the outflow pipe 5 through the fluid outflow passage 28 after entering the main body 2.
In this state, to perform the operation of turning off (cutting) the flow of the fluid, the coil 31 is energized so that the rotor unit 33 of the stepping motor 3 rotates forward. This allows
The rotor 33 rotates forward.

By the way, until the rotor 33 starts rotating, the protrusion 33b provided on the rotor 33 usually has its tip 33e at the tip side of the angular contact piece 50b provided on the rotor housing case 23 side. It is in a state of being separated from 50d in the axial direction. However, the rotor unit 3
3 is excessively reversely rotated, and when the projection 33b comes into contact with the square piece 50b and stops, the projection 33b moves to the tip side 50d.
(A state shown in FIG. 4).
When the rotor portion 33 starts rotating forward from this state, the projection 33b also rotates in the same direction, and eventually, the angular contact piece 50
b.

As described above, even when the rotor 33 is stopped by the contact with the tip side 50d during the reverse rotation stop, the rotor 33 smoothly rotates forward. That is, during the forward rotation operation of the rotor portion 33, the rotation of the rotor portion 33 can be smoothly performed without being restricted at all by the rotor restricting portion (configured by the projection 33b and the rotor restricting member 50). . Then, the rotational force of the rotor unit 33 is transmitted to the rotating shaft 34 via the friction spring 35, and the rotating shaft 34 also rotates.

That is, the friction spring 35 is wound around the rotating shaft 34 in a state where the friction spring 35 is tightened with a constant force (the initial tightening force originally possessed by the friction spring 35), and the first projection The portion 35a is the rotor portion 3
Since the third cylindrical member 331 is inserted into the slit 335, the rotation force is transmitted to the rotation shaft 34 by rotating the rotor unit 33. Thereby, the rotating shaft 34
Rotates together with the rotation of the rotor unit 33.

Further, since the male screw cut on the rotating shaft 34 and the female screw cut on the bearing 21 on the main body 2 are screwed together, the rotor 33 rotates forward (here, forward rotation). As a result, both the rotor portion 33 and the rotating shaft 34 linearly move inside the main body portion 2 toward the distal end thereof. And
Eventually, the valve portion 25c of the needle valve 25 in the carriage 24 attached to the tip of the rotary shaft 34 enters the fluid outflow passage 28 provided at the tip of the main body 2.

As described above, when the needle valve 25 enters the fluid outflow passage 28 of the main body 2, the needle valve 2
5, the gap between the outer peripheral surface of the valve portion 25c and the fluid outflow passage 28 gradually narrows. As a result, the flow rate of the fluid gradually decreases. Then, the valve portion 25c is connected to the fluid outflow passage 28.
Of the valve portion 25c and the inner peripheral surface of the fluid outflow passage 28 are brought into surface contact, and the gap is completely eliminated. Thus, the flow of the fluid can be reliably prevented.

In this embodiment, the needle valve 25
Before the tip of the valve portion 25c reaches the deepest portion of the fluid outflow passage 28 (the deepest portion where the needle valve 25 can advance),
It is possible to perform control to stop the stepping motor 33 and stop the needle valve 25 at an intermediate position. Thereby, the gap between the valve portion 25c and the fluid outflow passage 28 can be appropriately adjusted, and the flow rate of the fluid passing through the fluid outflow passage 28 can be adjusted.

The driving of the stepping motor 3 may be stopped in the above-mentioned state (a state in which the flow of the fluid is completely stopped). However, in order to absorb an assembly error or the like, the driving is usually continued further. However, the needle valve 25
Is pressed by the pressure spring 26. Then, a force that presses the fluid outflow passage 28 with a certain force or more acts on the needle valve 25 due to the extension force of the pressurizing spring 26, and a reliable contact state can be obtained.

The pressure spring 26 is connected to the needle valve 2
5 is pressed against the fluid outflow passage 28 to ensure a reliable contact state, and the needle valve 25 is always given a force for pressing against the leading end of the carriage 24. Sticking is prevented. Thereby, the needle valve 25 is caused by the pressure of the fluid.
Can be prevented from vibrating, and generation of noise due to the vibration of the needle valve 25 can be prevented.

When the rotor portion 33 is to continue rotating while the outer peripheral portion of the valve portion 25c of the needle valve 25 is in contact with the fluid outflow passage 28 of the main body portion 2 as described above, the friction mechanism is activated. work. That is, in a state where the needle valve 25 is in contact with the fluid outflow passage 28 of the main body 2 (a state where the gap is completely eliminated), the rotor 33
Is rotated, the rotational force causes friction spring 3 to rotate.
5, the first protrusion 35a also rotates, and the friction spring 35 also rotates, and the rotation shaft 34 also tries to rotate. However, at this time, the movement of the rotary shaft 34 is restricted by the needle valve 25 being in contact with the fluid outflow passage 28 of the main body 2 with a certain force or more,
You cannot move forward.

When the rotor section 33 further attempts to rotate in such a state, the rotational torque of the rotor section 33 is larger than the sliding torque of the friction spring 35 with respect to the rotating shaft 34. , And the rotor part 33 is in an idling state,
Further rotation of the rotating shaft 34 can be prevented.

From the state in which the fluid flow is turned off, this time, in order to turn the fluid flow to the on state (the state in which the fluid flows), the coil 31 is rotated so that the rotation of the rotor unit 33 is reversed. It is assumed that power is supplied. Then, the rotor unit 33 starts to rotate in the reverse direction. At this time, the needle valve 25
However, the rotating shaft 34 is in a state in which the rotating shaft 34 cannot advance because the fluid outflow passage 28 of the main body 2 is in a state of contact with a certain force or more. If you try to move backward in this state,
It tends to be in a state where the rotational force of the rotor section 33 cannot be transmitted to the rotating shaft 34 via the friction spring 35 (a state in which the rotor mechanism 33 idles due to the operation of the friction mechanism). Becomes

That is, in this friction mechanism, when the rotor portion 33 rotates in the reverse direction, the friction spring 35 inserted into a slit (not shown) of the cylindrical member 331 is inserted.
The first projection 35a also tends to move in the reverse rotation direction. Since the friction spring 35 is a right-handed coil spring as described above, when the rotor portion 33 rotates in the reverse direction, the first protrusion 35a operates to reduce the inner diameter of the friction spring 35, that is, the friction spring 35 Performs an operation of tightening the rotating shaft 34 more.

As a result, the rotational force of the rotor section 33 is transmitted to the rotating shaft 34, and the rotating shaft 34 performs a reverse rotation operation together with the rotor section 33, moves in a direction to exit the main body 2, and the stepping motor 3 is moved. When the needle valve 25 is operated by a predetermined number of steps, the needle valve 25 is engaged with the leading end of the carriage 24. Thereafter, when the rotor portion 33 further rotates in the reverse direction, the needle valve 25 starts to move together with the carriage 24, separates from the fluid outflow passage 28 of the main body portion 2, and enters a state in which fluid flows (on state).

As described above, after the rotor portion 33 is rotated in the reverse direction by a predetermined number and the fluid flows, the rotor portion 33 is rotated.
Is further restricted (reverse rotation) by the rotor restricting portion described above. That is, from a state in which the needle valve 25 is in contact with the fluid outflow passage 28 so that no gap is formed, the needle valve 25 is separated from the fluid outflow passage 28, and a state in which fluid flows (on state), and further reverse rotation is continued The number of rotations of the rotor unit 33 until it stops after stopping is set in advance.

For some reason, the rotor section 33 continues to rotate more than necessary, or the rotating shaft 34 moves too much to the inner bottom surface side of the rotor housing case 23 before the required number of rotations. Can occur. In such a case, even if the rotor unit 33 attempts to rotate (reverse rotation) further,
The rotation is regulated. In particular,
When the rotor portion 33 returns to the predetermined axial position, the tip 33e of the protrusion 33b of the rotor is set to contact the tip side 50d of the angular contact piece 50b.

At this time, as described above, the rotor 33
Of the protrusion 33b and the tip side 5 of the angular contact piece 50b
Since 0d has the same angle of inclination, as shown in FIG. 4, the tip side 33e of the projection 33b and the angular contact piece 50
The leading edge 50d of b is in contact with almost the entirety. For this reason, a reliable contact state can be obtained, the setting accuracy of the contact position can be increased, and the rotation of the rotor portion 33 can be reliably and accurately regulated.

As described above, the tip 33e of the projection 33b of the rotor portion 33 and the tip side 50d of the angular contact piece 50b are inclined at the same angle in order to obtain a reliable contact state. In other words, if the tip 33e of the protrusion 33b of the rotor 33 has a shape without inclination, as shown in FIG. 4, when the rotor 33 rotates reversely a predetermined number of times, the angular contact piece of the protrusion 33b The contact state with respect to 50b is close to a point contact with only the corner of the projection 33b, and a reliable contact state cannot be obtained.

In addition, a slight displacement of the tip of the square piece 50b causes a displacement of the rotation stop position, making it difficult to ensure the accuracy of the stop position. For this reason, there is a possibility that the rotation of the rotor unit 33 cannot be reliably and accurately regulated. In order to prevent these, the tip 33e of the protrusion 33b of the rotor 33 and the tip side 50d of the angular contact piece 50b are inclined at the same angle.

Note that, in the present embodiment, as described above,
Not only complete off / on but also fine adjustment of the flow rate is possible. That is, the valve portion 25c of the needle valve 25
Before the outer peripheral surface of the needle valve 2 comes into contact with the inner peripheral surface of the fluid outflow passage 28, the stepping motor 33 is stopped and the needle valve 2 is stopped.
5 can be stopped at an intermediate position.

As described above, in this embodiment, the needle valve 25 held by the carriage 24 is moved to the main body 2 by moving the carriage 24 toward the fluid outflow passage 28 of the main body 2 by the stepping motor 3. The provided fluid outflow passage 28 is closed to close the fluid outflow passage 28. On the other hand, by moving the carriage 24 away from the distal end of the main body 2, the needle valve 25 can be brought into a state in which there is a predetermined gap with respect to the fluid outflow passage 28, and the open state of the fluid outflow passage 28 is changed. Can be fine-tuned.

In addition, when the stepping motor 3 used in this embodiment is rotated in the reverse direction after the rotor section 33 rotates forward and stops the flow of fluid, the stepping motor 3 rotates at a predetermined rotational speed or more. Reverse rotation, that is, the rotor unit 33
Has a rotor restricting portion for restricting a movement of a predetermined amount or more in the axial direction. Thus, after the rotor section 33 moves in the axial direction by the allowable movement amount, the movement of the rotor section 33 accompanying the movement can be surely restricted, and the rotor section 3
3 can be reliably stopped at a predetermined position.

The rotor restricting portion is provided with the rotor portion 3
The protrusions 33b provided on the 3 side and the rotor restricting member 50 provided on the rotor housing case 23 side can be realized only with two simple components, and reliable and accurate restriction can be performed.
Further, at least during the forward rotation of the rotor section 33, no impulsive sound is generated between them. Also, at the time of reverse rotation, there is a possibility that the projection 33b and the angular contact piece 50b may come into contact with each other, but this does not always occur.
In other words, the rotation of the rotor unit 33 is set to stop before the two members come into contact with each other, and this is a regulation in preparation for the case where the rotation is further continued. Not necessarily. Therefore, the noise due to the impact sound during the regulation operation can be minimized.

Further, in this embodiment, a coil spring is used as the friction spring 35 as a friction mechanism of the stepping motor 3, and when the rotor 33 rotates in the forward rotation direction, the desired tightening force of the friction spring 35 is applied. The rotational force of the rotor section 33 is
And the rotation shaft 34 can be rotated. When a large load is applied to the rotating shaft 34 in the rotating state, the friction spring 35
With the rotation of 3, the rotor portion 33 rotates by sliding on the rotation shaft 34, causing the rotor portion 33 to idle, so that the rotation shaft 34 can be prevented from further forcibly moving. For this reason, it is possible to avoid a locked state when the rotating shaft 34 moves in the forward direction.

On the other hand, if the rotor 33 is rotated in the reverse direction in order to return the rotating shaft 34 to the original state from such a state, the friction spring 35 tightens the rotating shaft 34 with a large force. Make sure the rotating shaft 3
4 can be transmitted. Therefore, even if the rotation shaft 34 is locked, the rotation shaft 3 is changed from that state.
4 is to be returned to the original position, the rotor portion 33
Can be reliably transmitted to the rotating shaft 34, and the locked state can be released.

As described above, in the motor shown in this embodiment, the rotor 33 is rotated forward and the rotating shaft 3
It can be said that the motor is an optimal motor as a drive source when performing a series of operations of performing a certain operation using the movement of No. 4 and then rotating the rotor unit 33 in the reverse direction to return to the original state.

Further, since the communication passage 21g is provided in the bearing portion 21, oil such as ester oil which has entered the rotor storage case 23 can be easily drained. Further, this communication passage 21g not only removes oil but also allows the main body 2
It can also be used as an introduction path when filling the inside with a refrigerant, for example, chlorofluorocarbon gas.

In this embodiment, the main body 2 is joined to the inflow pipe 4 and the outflow pipe 5, and the main body 2 is connected to the flange plate 22.
Is performed by silver brazing in a hydrogen reduction furnace, so that post-processing for applying a flux and removing an oxide film after silver brazing can be eliminated.

In the fluid flow control device 1 of this embodiment, the tip of the rotary shaft 34 on the needle valve 25 side protrudes from the tip of the opening of the carriage 24 in which the pressure spring 26 is inserted. Then, the needle valve 25 is fixed by caulking by bending the distal end portion of the opening. An inclined surface is formed at a contact portion of the needle valve 25 with the carriage 24.

For this reason, the needle valve 25 is
4, the rear end portion of the needle valve 25 comes into contact with the tip of the rotating shaft 34, which causes a problem when the pressing spring 26 is compressed, for example, when the pressing spring 26 sinks in the carriage 24. It is possible to avoid problems such as being unable to return, and fixing the rear end portion of the needle valve 25 at a position inclined in the carriage 24.

Although the above-described embodiment is an example of a preferred embodiment of the present invention, the present invention is not limited to this, and various modifications can be made without departing from the gist of the present invention. is there. For example, in the above embodiment,
Although one end of the friction spring 35 is engaged with the rotor section 33 and the other end is free, the other end may be engaged with the rotating shaft 34.

Further, in the above-described embodiment, the example in which the stepping motor 3 is used as the motor for driving the needle valve 25 serving as a valve has been described. A mechanism other than a motor such as a solenoid may be adopted as a source.

In the above-described embodiment, the coil-shaped pressure spring 26 is used as a spring for applying a force for pressing the needle valve 25 to the tip of the carriage 24. However, this pressure spring is a coil-shaped spring. It is not necessary. For example, a leaf spring is used, and the elastic force of the leaf spring makes use of the needle valve 25.
Can be pressed against the leading end of the carriage 24.

Further, the holder 40 for holding the stator housing 38 in the main body 2 is not limited to the structure of the above-described embodiment. Any other structure may be used as long as a suitable engagement relationship can be obtained. Further, the protrusion of the holder 40 may be formed in a convex shape instead of the claw shape, or the locking claw 40c of the holder 40 may be changed to another shape such as an acute angle shape.

Further, the shape of the rotor restricting member 50 provided on the rotor storage case 23 side is not limited to the shape shown in the above-described embodiment, but is one end of the elastic thin plate-shaped rotor restricting member. The rotor storage case 23
May be employed as long as the other end (tip side 50d) is positioned at a predetermined height in the rotation locus of the rotor section 33. Further, for fixing the rotor regulating member 50, other fixing means such as adhesive fixing and press-fitting fixing can be adopted other than spot welding.

[0114]

As described above, according to the flow control device of the present invention, the adjusting valve constituted by the needle valve is provided at the tip portion of the rotating shaft of the motor by the "biasing" by the force of "caulking" and the spring. The holding member held by the force is fixed, and the needle valve is moved in the flow path by the driving force of the motor. For this reason, the needle valve faces the flow path (the opening formed in the main body) with some play, and strictly faces the needle valve, so that it is not necessary to set dimensions so precisely at the time of design. it can. Therefore, assembling costs and parts costs can be significantly reduced, which can contribute to an improvement in productivity.

Further, the conversion means for converting the rotational force of the rotor into the propulsion force in the linear direction is constituted by a male screw and a female screw, and is provided at a position where the male screw is not deformed by caulking (for example, a member separate from the holding member). ), The screws can be screwed together smoothly and accurately.

In addition to the screwing of the screws, the rotational force is converted into propulsive force by sliding the portion of the rotary shaft where the male screw is not formed and the cylindrical portion on the main body side. It is not necessary to make the dimensions of the screws so strict. Therefore, assembling costs and parts costs can be significantly reduced, which can contribute to an improvement in productivity.

Further, in the flow control device of the present invention, when the rotor section is rotated in the forward direction and linearly moves to a certain position, and then the rotor section is rotated in the reverse direction, the predetermined position is determined. Since the rotor has the rotor regulating member that regulates the reverse rotation of the rotor, even if the rotor continues to rotate in the reverse direction, when the rotor returns to the predetermined position, the movement of the rotor can be reliably restricted, The rotor section can be reliably stopped at a predetermined position. Therefore, the flow rate control of the fluid can be performed stably and efficiently.

The rotor restricting member can be realized with only two simple components, ie, a protrusion provided on the rotor portion side and a rotor restricting member provided on the rotor storage case side, and can perform reliable restriction. Further, when the rotor portion rotates forward, no impulsive sound is generated between the two, and noise can be suppressed as much as possible.

[Brief description of the drawings]

FIG. 1 is a side sectional view of a flow control device according to an embodiment of the present invention.

FIG. 2 is a side sectional view showing a vicinity of a needle valve of the flow control device of FIG. 1;

FIG. 3 is a partially enlarged view showing a distal end portion of the needle valve of FIG. 2;

FIG. 4 is a partial cross-sectional side view showing a state in which a protrusion of a rotor unit abuts a rotor regulating member.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Flow control device 2 Main body part 3 Stepping motor 4 Inflow pipe 5 Outflow pipe 21 Bearing part (part of conversion means) 21a Rotary shaft support through hole (part of conversion means) 23 Rotor storage case 24 Carriage (holding member) 25 Needle valve (adjusting valve) 26 Pressurizing spring (biasing member) 28 Fluid outflow path (opening) 31 Coil 32 Stator part 33 Rotor part 33b Projection (part of rotor regulating part) 34 Rotary shaft (part of conversion means) 50 Rotor regulation member (part of rotor regulation section)

Claims (4)

[Claims] 1. A tubular main body connected to an inflow pipe for inflowing a fluid and an outflow pipe for outflow of the fluid, and having an opening for adjusting a flow rate of the fluid, In a flow control device having a regulating valve that is movable in a state where the distal end side is inserted, and adjusts a flow rate of a fluid according to the insertion position, and a motor for driving the regulating valve, the motor rotates. A rotor portion that holds a shaft, and a stator portion that is arranged to face the rotor portion, and the rotor portion rotates in a predetermined direction (referred to as a forward rotation), so that the rotor portion and the rotor The rotation axis moves linearly in the direction toward the opening, and the rotor rotates in a direction opposite to a predetermined direction (referred to as reverse rotation).
By doing so, the rotor portion and the rotating shaft are configured to linearly move in a direction away from the opening, and further, a conversion means for converting the rotating motion of the rotor portion into a linear motion, A holding member that is fixed and holds the adjustment valve, and wherein the holding member is open at one end, and the adjustment valve is internally provided such that a distal end side of the adjustment valve protrudes from the open end. A biasing means for bending the open end inward and caulking the adjustment valve, and for urging the adjustment valve to the open end side. A flow control device, wherein the regulating valve is sandwiched between a bent portion at an open end and the bent portion. 2. The converting means has a male screw formed at a position where it is not deformed when the holding member is crimped, and a female screw which is screwed to the male screw. The flow control device according to claim 1, wherein a tapered surface is provided on one of the outer circumferences of the valve, and the other is a straight surface. 3. The converting means includes forming the male screw on the rotating shaft, forming the female screw on the main body side, and forming a straight portion on which the male screw is not formed on the rotating shaft. The flow control device according to claim 1, wherein a cylindrical portion is formed on the main body portion side such that an inner periphery of the straight portion is in sliding contact with the straight portion. 4. A tubular main body having an opening for adjusting a flow rate of a fluid, the cylindrical body being connected to an inflow pipe for inflowing a fluid and an outflow pipe for outflow of the fluid; In a flow control device having a control valve movable in a state where the distal end side is inserted, and adjusting a flow rate of fluid according to the insertion position, and a motor for driving the control valve, the motor is rotated. A rotor portion having a shaft, a bottomed rotor storage case for storing the rotor portion, and a stator portion disposed outside the rotor storage case so as to face the rotor portion; By rotating the portion in a predetermined direction (referred to as forward rotation), the rotor portion and the rotation shaft can be linearly moved in a direction away from the inner bottom surface of the rotor storage case, and the rotor portion can be rotated in a predetermined direction. By rotating in the direction opposite to the direction (called reverse rotation), the rotor portion and the rotating shaft can linearly move in a direction toward the inner bottom surface of the rotor storage case, and the rotor portion has A protrusion is provided on an end surface facing the inner bottom surface of the rotor storage case, and a plate-like rotor restricting member having elasticity is provided on the inner bottom surface side of the rotor storage case. It is fixed to the inner bottom surface of the storage case, the tip side is provided within the rotation locus of the protrusion, and is located at a predetermined height from the inner bottom surface of the rotor storage case, and when the rotor portion rotates forward, When the protrusion advances down the rotor regulating member along the rotor regulating member toward the tip end of the rotor regulating member so as to be able to push down the rotor regulating member, and when the rotor rotates in the reverse direction, the rotor moves to a predetermined position. When returning, the protrusion is configured to abut on the rotor regulating member to prevent rotation, and further, a conversion means for converting the rotational motion of the rotor portion into a linear motion, and fixed to a tip side of the rotary shaft. And a holding member that holds the adjustment valve,
And the holding member is formed of a tubular member that houses the adjustment valve therein such that one end thereof is opened and a distal end side of the adjustment valve projects from the open end. Bending inward and caulking the adjustment valve, and biasing means for biasing the adjustment valve toward the open end, wherein the biasing means and the bent portion of the open end sandwich the adjustment valve. A flow control device characterized by the above-mentioned.