JPH09296868A - Motor-operated valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make fine adjustment achievable even in time of being much in discharge by having a valve member seated at the tip of a seat end of an annular valve seat part, interrupting the discharge, and carrying out a discharge regulation in space between a holding member lower end part and a seat end outer side part. SOLUTION: A valve stem 21 shifts in the vertical direction by rotation of a pulse motor by a pulse signal as far as a quantity proportioned to the amount of this pulse signal. With this movement, clearance width a0 to a3 between a seat end part 14a of a valve seat part 14 and a chamfer square part 42c of a valve element 40 is adjusted, regulating a flow quantity of fluid flowing in a clearance. In addition, a complete closing cutoff between the annular valve seat part 14 and the valve element 40 is carried out by way of having a valve closing member 41 contacted and seated at a tip of the seat end part 14a of the annular valve seat part 14. In the usual adjustment of a flow quantity, the clearance width a0 to a3 is regulated, for example, within the range of about 0 to 3mm. In the case where it is regulated by means of throttling the discharge, it is regulated as a minute clearance of about 10 to 50μ or so.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric valve for opening and closing a valve body by an electric motor such as a pulse motor, and more particularly to a structure of a valve body portion of the electric valve capable of adjusting a minute flow rate.

[0002]

2. Description of the Related Art Conventionally, a motor-operated valve has been used as a device, such as a heating device, which is interposed in the middle of a piping system for a hot water fluid to open and close a flow path of the hot water fluid. The motor-operated valve includes an electric motor such as a pulse motor mounted on the valve body, a valve stem mounted in the valve body and driven by the pulse motor, a valve body mounted and fixed to one end of the valve stem, And a valve opening / closing portion including a valve seat portion formed in the valve body.

FIG. 6 shows a valve opening / closing portion of the conventional motor-operated valve 50. A valve body 51 has pipe connecting portions 52 and 53 on both sides thereof, and a plug 59 is screwed to a lower portion thereof. The opening 58 is provided. An upper portion of the plug 59 of the valve body 51 is configured as a valve chamber 55, and a valve body 57 is arranged in the valve chamber 55. The valve body 57 is attached and fixed to a valve stem 60 which is vertically slidable. An inlet side passage 52a is formed in the pipe connecting portion 52, and an outlet side passage 53a is formed in the pipe connecting portion 53.
The passages 52a and 53a are connected to the valve chamber 55.

A valve seat portion 61 is formed at a connecting portion between the inlet side passage 52a and the valve chamber 55, while the valve body 5 is provided.
7 includes a valve member 57a that contacts the valve seat portion 61. A portion of the valve member 57a that comes into contact with the valve seat portion 61 is formed as a convex annular taper portion whose diameter is enlarged in the valve chamber 55 direction, and the convex annular taper portion is provided on the valve seat portion 61. It is configured to make surface contact with the concave annular taper portion.

An electric motor (not shown) is attached to the upper portion of the valve body 51, and the valve stem 60 slides up and down by the rotation of the electric motor, so that the valve body is moved relative to the valve seat portion 61. 57 (valve member 57a) is freely movable to open and close the valve body 57. By the opening / closing operation, the fluid from the inlet side passage 52a is blocked or circulated by the valve portion 57.

When the motor-operated valve 50 is used by interposing it in the middle of a piping system of a hot water fluid such as a heating device, usually, the valve stem 60 is vertically slidably moved, that is, a valve for the valve seat portion 61. The contact / separation movement of the body 57 is, for example, 0 to 3
Move a range of about mm. By the movement, the opening gap between the valve seat portion 61 and the valve body 57 is adjusted to adjust the flow rate of the fluid. However, when the flow rate needs to be further reduced, the valve seat portion is adjusted. The gap between the valve element 61 and the valve element 57 is set as a minute gap of, for example, about 10 μ to 50 μ.

[0007]

By the way, in the structure of the valve seat portion 61 and the valve body 57 of the conventional motor-operated valve 50 shown in FIG. 6, the valve stem 60 is vertically slidably moved (the valve seat portion 61).
The movement between the valve body 57 moving toward and away from the
Since the valve body 57 changes substantially linearly from the beginning of opening, it is difficult to accurately perform the fine adjustment when the flow rate of the fluid is finely adjusted. That is, the valve seat portion 6 with respect to the number of pulses which is an output signal for vertically sliding the valve stem 60, that is, for urging the electric motor.
1 and the valve body 57 linearly change the separation distance (flow rate adjustment gap), and even when adjusting the minute flow rate, the opening gap changes at substantially the same rate as when adjusting the large flow rate. Therefore, there is a problem that the fine flow rate cannot be adjusted accurately.

The valve body 51 (valve seat portion 61) of the motor-operated valve 50 may be made of brass, while the valve member 57a of the valve body 57 may be made of synthetic resin such as Teflon. Since the different materials used have different coefficients of thermal expansion, when hot water having a temperature difference is passed instead of the low temperature fluid, the valve seat portion 61 and the valve member 57a of the valve body 57 are As the temperature of both members increases, both members expand and expand their diameters, but since the coefficient of thermal expansion of synthetic resin such as Teflon is larger than that of brass, the valve member 57a has a larger expansion amount. Expand its outer diameter. Due to the difference in the expansion amount, the valve seat portion 61 and the valve member 57a of the valve body 57, which are arranged as shown in FIG. 6, act in a direction to narrow the opening gap set in the state of the room temperature water, and This is a factor that hinders accurate adjustment of the minute flow rate.

The present invention has been made in view of the above problems, and an object thereof is to accurately and minutely adjust the fluid passing through the valve body portion of the motor-operated valve. An object of the present invention is to provide an electrically operated valve having a structure of a valve body and a valve seat portion that can be made fine and can be adjusted even in a state where a large amount of flow is present.

[0010]

[Means for Solving the Problems] To achieve the above object,
In the electrically operated valve according to the present invention, a valve body driven by an electric motor is brought into contact with and separated from a valve seat, the valve seat comprises an annular valve seat portion, and the valve body has a valve member and an outer periphery of the valve member. A holding member for holding the valve member, the valve member is seated on the tip of the seat end of the annular valve seat portion to shut off the flow rate, and the flow rate between the lower end portion of the holding member and the outer side portion of the seat end portion. It is characterized by adjusting.

As another aspect of the motor-operated valve according to the present invention, the motor-operated valve includes a valve main body, an annular valve seat portion formed in the valve main body, a valve body, and a valve stem for moving the valve body. Equipped with
The valve body includes a valve closing member made of a disc-shaped elastic body that is seated on the annular valve seat portion, and a valve closing member holding outer collar having an annular collar portion that is located on the outer periphery of the valve closing member. The lower end portion of the annular collar portion of the closing member holding outer collar is positioned on the outer periphery of the seat end portion of the annular valve seat portion, and is located between the lower end portion of the annular collar portion and the seat end portion of the annular valve seat portion. The feature is that the flow rate is adjusted by the gap.

As a specific mode of the motor-operated valve of the present invention, the seat end portion of the annular valve seat portion has a semicircular sectional shape or a tapered outer peripheral sectional shape,
The lower end portion of the annular collar portion of the valve closing member holding collar projects downward from the lower surface of the valve closing member and has a chamfered corner portion inside.

The motor-operated valve of the present invention thus constructed is
The fluid that has flowed in through the inlet-side passage of the motor-operated valve passes through the opening gap between the annular valve seat portion and the valve body, and is discharged through the outlet-side passage through the valve chamber. At this time, when the electric motor is rotated by a pulse signal or the like, the rotation causes the valve stem to slide up and down, and the vertical position of the valve body is moved by an amount proportional to the number of the pulse signals, thereby causing the annular valve seat to move. The opening gap between the valve section and the valve body is adjusted to adjust the flow rate of the fluid flowing through the opening gap. When completely closing and shutting off the fluid flowing between the annular valve seat portion and the valve body, the lower surface of the valve closing member of the valve body is seated at the tip of the seat end of the annular valve seat portion. It is performed by making a thick contact.

The adjustment of the fluid flowing between the annular valve seat portion and the valve body is performed by the lower end portion of the annular collar portion of the outer collar holding the valve closing member and the outer peripheral portion of the seat end portion of the annular valve seat portion. The flow rate is adjusted by adjusting the width of the opening gap between them.

In the electrically operated valve of the present invention, the seat end of the annular valve seat has a semicircular cross section, and the lower end of the annular collar of the outer collar for holding the valve closing member is lower than the lower surface of the valve closing member. By projecting downward and providing a chamfered corner portion inside, in the initial stage of movement from the closed position of the valve body,
Since the opening width between the chamfered corner portion and the seat end portion of the annular valve seat portion is slightly widened with respect to the vertical movement distance of the valve body, a minute opening gap can be adjusted. ,
Fine adjustment of the fluid flow rate is possible.

[0016]

An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a longitudinal sectional view of an electric valve 10 according to this embodiment, and FIG. 2 is an exploded perspective view of a valve body 40 and a valve stem 21 of the electric valve 10.
For example, the valve main body 11 made of a material such as brass has a holder connecting portion 19 provided upright on the upper portion thereof, and a holder 20 made of the same material is fitted and fixed to the holder connecting portion 19. An electric motor 31 such as a pulse motor is mounted and fixed on the holder 20 via an insulating flange 32 made of synthetic resin, for example.

On both sides of the valve body 11, threaded pipe connecting portions 12 and 13 are provided at different positions vertically, and a lower portion 18 of the valve body 11 is hermetically sealed. There is. A valve chamber 15 is formed in the valve body 11, and an upper portion of the valve chamber 15 is closed by the holder 20 fitted to the holder connecting portion 19. The valve chamber 1
A valve body 40 is arranged in the valve 5, and the valve body 40 is attached and fixed to a valve stem 21 slidably supported by the holder 20.

In the pipe connecting portion 12 of the valve body 11,
An inlet side passage 12a is bored, and an outlet side passage 13a is bored in the pipe connecting portion 13, so that both passages 1a
2a and 13a are connected to the valve chamber 15 for communication. The holder 20 is inserted and fitted into the inner space 19a of the holder connecting portion 19 above the valve chamber 15 with the outer O-ring 22 interposed therebetween, and the lock nut 23 is engraved on the outer periphery of the holder connecting portion 19. The holder 20 is attached and fixed to the valve body 11 by being screwed into the screw.

The intermediate portion of the valve stem 21 is slidably supported by the holder 20 with a pair of O-rings 29, 29 interposed therebetween, and the upper end of the valve stem 21 is enlarged so that the drive shaft holding portion is enlarged. 21a is formed. The drive shaft holding portion 21a
Is provided with a concave portion 21b, and the lower end portion 25a of the drive shaft 25 is inserted into contact with the concave portion 21b with a hard sphere 24 interposed therebetween. 26 is engaged. An intermediate portion of the drive shaft 25 is a male screw portion 25c, which is screwed into a female screw 27a formed on a drive shaft guide 27 fixedly attached to the holder 20. A coil spring 30 is interposed between the lower surface of the drive shaft holding portion 21a and the in-cylinder upper surface of the holder 20 to constantly urge the valve stem 21 upward.

FIG. 3 shows the structure and operating state of the valve body 40. FIG. 3 (a) shows the closed state of the valve body 40, and FIG. 3 (b) shows the opening. It shows the state. As shown in FIGS. 3A and 3B, an annular valve seat portion 14 is formed on the valve chamber 15 side of the connecting portion between the inlet side passage 12 a and the valve chamber 15, and the annular valve seat portion 14 is formed. The seal end portion 14a of the valve seat portion 14 is formed in a semicircular shape having a radius R in cross section. The valve stem 21 is provided with a shaft end portion 21b for mounting and fixing the valve body 40 on a lower portion thereof,
As shown in FIGS. 2 and 3, the valve body 40 includes three members, that is, a valve closing member 4 that closes by contacting the valve seat portion 14.
1, a valve closing member holding outer collar 42, and a valve closing member holding inner collar 43, and the three members are fitted with the shaft end portion 21b of the valve stem 21 at the center thereof. By crimping the end of the portion 21a, the valve stem 2
1 attached and fixed.

The valve closing member 41 of the valve body 40 is formed of an elastic body made of a synthetic resin such as rubber material or Teflon and has a disc shape, and the valve closing member holding outer collar 42 and the valve closing member. The member holding inner collar 43 is formed of a material such as SUS, and the valve closing member 41 is sandwiched between the collars 42 and 43. The outer collar 42 for holding the valve closing member has an annular collar 4 on the outer periphery thereof.
2a, the lower end portion 42b of the annular collar portion 42a extends below the lower surface of the valve closing member 41, and when the valve body 40 is in the closed state (FIG. 3A), The annular valve seat portion 14 is formed so as to be arranged with an extremely small gap on the outer peripheral surface thereof.

In closing and adjusting the flow rate between the valve body 40 and the annular valve seat portion 14, the valve closing member 41 of the valve body 40 is closed to close the seat end portion 14 of the annular valve seat portion 14.
The lower end portion 42b of the valve closing member holding outer collar 42 is used for adjusting the flow rate by contacting with the tip of a and seating.
This is performed by adjusting the gap a between the inner peripheral portion of the above and the outer arc-shaped portion of the seat end portion 14a of the annular valve seat portion 14.

FIG. 4 shows in more detail the positional relationship between the annular valve seat portion 14 and the lower end portion 42b of the valve closing member holding outer collar 42 during flow rate adjustment. The lower end portion 42b of the collar 42 is chamfered on its inner peripheral portion, and when the valve is closed, the chamfered corner portion 42c is formed.
Is placed on the outer surface of the semi-circular seat end portion of the annular valve seat portion 14 with a very small gap, but raises the valve element 40 to move the electric valve in the opening direction. And the gap width a between the chamfered corner portion 42c and the outer surface of the semi-circular seat end portion of the annular valve seat portion 14 is gradually increased.

Specifically, when the valve body 40 moves up from the closed position L ₀ to the position b ₁ by the distance b and moves to the open position L ₁ , the chamfered corner portion 4 of the valve closing member holding outer collar 42.
The gap width between 2c and the seat end portion 14a of the annular valve seat portion 14 is a ₁ . Then, when the same distance b further rises to move to the position L ₂ in the open state, the chamfered corner portion 42 is moved.
gap width c and the sheet edge 14a of the annular valve seat 14 is a a _2, the gap a ₂ is the width whereas increasing distance of the valve body 40 is moved to 2b and double For example, it changes to twice or more than a ₁ . That is, the gap width a between the chamfered corner portion 42c and the seat end portion 14a of the annular valve seat portion 14 does not change linearly with respect to the moving distance of the valve body 40, but does not change linearly. Change. In other words, in the initial stage of movement of the valve body 40 from the closed position, the gap between the chamfered corner portion 42c and the seat end portion 14a of the annular valve seat portion 14 with respect to the moving distance L of the valve body 40. The width a expands the gap width only a little, and fine adjustment of the gap can be performed to enable fine adjustment of the fluid flow rate. The reason why this fine adjustment can be performed is that the cross-sectional shape of the seat end portion 14a of the annular valve seat portion 14 is formed in a semicircular shape having a radius R.

When the moving position of the valve body 40 becomes L ₃ or more, the adjustment of the flow rate is less influenced by the semicircular shape, and becomes substantially linear with respect to the moving distance of the valve body 40. It will change.

FIG. 5 shows the moving distance of the valve body 40, that is,
It is the graph which experimentally calculated | required the relationship between the number of valve-opening pulses for rotating the said electric motor 31, and a flow rate, The area | region I with few valve-opening pulses was used for fine flow rate adjustment, and the number of valve-opening pulses beyond it. Area II, which has a lot of air, is used for normal flow rate adjustment. From FIG. 5, in the region I where the number of valve opening pulses is small,
It is understood that the flow rate changes little with respect to the change of the pulse number, and the minute flow rate adjustment is performed, and the change of the flow rate with respect to the change of the pulse number is larger than that of the region I in the region II where the number of pulses is large. Will.

Next, the operation of the motor-operated valve of this embodiment will be described. A fluid such as water or hot water supplied from the supply source of the heating device is supplied from the inlet-side passage 12 a, passes through the gap between the annular valve seat portion 14 and the valve body 40, and then passes through the valve chamber 15. It is delivered to a device such as a heater through the outlet passage 13a. At this time, the electric motor 31 such as a pulse motor
Is rotated by a pulse signal or the like, the motor 3
The rotating shaft 26 of No. 1 rotates, and the drive shaft 25 engaged with the rotating shaft 26 is rotated. The rotation of the rotary shaft 25 causes the rotary shaft 25 itself to move up and down, thereby sliding the valve stem 21 up and down. The valve stem 21 moves in the vertical direction by an amount proportional to the amount of the pulse signal, and the gap width between the seat end 14a of the valve seat portion 14 and the chamfered corner portion 42c of the valve body 40. By adjusting a, the flow rate of the fluid flowing through the gap having the width a is adjusted. Further, the complete closure / shutoff between the annular valve seat portion 14 and the valve body 40 is performed by the valve closing member 41 contacting with the tip of the seat end portion 14a of the annular valve seat portion 14 and seating.

The normal adjustment of the flow rate of the fluid is carried out by adjusting the width a of the gap between the valve seat portion 14 and the valve body 40 within a range of 0 to 3 mm, for example. However, when the adjustment is performed by narrowing the flow rate, the width a of the interval is
The area I in a narrowed state, that is, a minute gap of about 10 to 50 μm is used to adjust the flow rate of hot water.

In the present embodiment, the annular valve seat portion 14
And a lower end portion 42b for adjusting the flow rate of the valve closing member holding outer collar 42 of the valve body 40 are both formed in an annular shape, and the fluid from the inside of the annular valve seat portion 14 is an outer annular valve seat portion 14
By flowing in the radial skirt shape as shown by the arrow in FIG. 3B toward the lower end 42b of the valve closing member holding outer collar 42 located on the outer periphery of the valve closing member 40, centripetal force acts on the valve member 40, and the valve member 40 itself. Stable operation with less blurring.

Further, in this embodiment, the chamfered corner portion 42c and the semi-circular seat end portion 14a of the annular valve seat portion 14 which constitute the flow rate adjusting portion can be formed with relatively easy machining accuracy. Furthermore, the valve body 40 of the present embodiment includes the closing valve member 4
The outer circumference of 1 is the annular portion 42a of the outer collar 42 for holding the valve closing member.
Since it is completely covered by the above, it is possible to regulate the influence of thermal expansion due to the material (Teflon or the like) of the closing valve member 41.

Furthermore, in the present embodiment, the valve closing member 41, which is made of a material having a good closing property, such as Teflon, is used for completely closing and shutting the electric valve, and the flow rate is adjusted by using a material such as brass. Since the annular valve seat portion 14 and the valve closing member holding outer collar 42 made of a material such as SUS are formed so as to be made of metals having similar thermal expansion coefficients, even if the flowing fluid changes in temperature, the flow rate adjustment is not necessary. A valve portion that is less affected by thermal expansion can be configured, and an electrically operated valve suitable for adjusting a minute flow rate of a fluid can be provided.

In the present embodiment, the electric valve has been described as being implemented in the hot water supply device of the heating equipment, but the electric valve of the present invention is not limited to the above embodiment,
It can also be used as a valve arranged in a pipeline for supplying a refrigerant and as a valve for an oil supply pipeline used as a cooling liquid.

Further, in the present embodiment, the seat end of the annular valve seat is shown to have a semicircular cross section, but the present invention is not limited to this shape, and the outer peripheral portion of the seat end is not limited to this. It is also possible to make the sectional shape of the taper into an inclined shape so that a minute flow rate can be adjusted. Further, in the present embodiment, the inside of the lower end portion of the annular collar portion of the valve closing member holding collar is chamfered to be provided with the chamfered corner portion, but the chamfering is not performed and the inner corner portion of the lower end portion is not chamfered. It can also be used as a flow rate adjusting unit.

[0034]

As can be understood from the above description, in the motor-operated valve of the present invention, the lower end portion of the annular collar portion of the valve closing member holding collar of the valve body is located on the outer periphery of the seat end portion of the annular valve seat portion. Therefore, since the flow rate is adjusted by the gap between the lower end of the annular collar portion and the seat end of the annular valve seat portion, both normal flow rate adjustment and minute flow rate adjustment performed as necessary are performed. The adjustment can be performed accurately and smoothly.

[Brief description of drawings]

FIG. 1 is a vertical sectional view of an electric valve according to an embodiment of the present invention.

FIG. 2 is an exploded perspective view of a valve body and a valve stem of the electric valve of FIG.

FIG. 3 is an operational cross-sectional view showing an operational state ((a) closed, (b) open) of a valve body and an annular valve seat portion of the electric valve of FIG. 1.

FIG. 4 is an enlarged operation cross-sectional view showing a flow rate adjustment state of the electric valve of FIG.

5 is a relationship diagram between a valve opening pulse and a flow rate of the motor-operated valve of FIG.

FIG. 6 is an enlarged cross-sectional view of a main part of a conventional electric valve.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 ... Electric valve 11 ... Valve main body 14 ... Annular valve seat part 14a ... Seat end part 15 ... Valve chamber 21 ... Valve stem 31 ... Electric motor 40 ... Valve body 41 ... Closing valve member 42 ... Closing valve member holding outer collar 42a ... Annular Collar part 42b ... Lower end part 43 ... Closure valve member holding inner collar

Claims (5)

[Claims] 1. A motor-operated valve in which a valve body driven by an electric motor comes into contact with and separates from a valve seat, wherein the valve seat comprises an annular valve seat portion, and the valve body has a valve member and an outer periphery of the valve member. And a valve member is seated at the tip of the seat end of the annular valve seat to block the flow rate, and between the lower end of the holding member and the outer side of the seat end. A motorized valve characterized by adjusting the flow rate. 2. A motor-operated valve comprising a valve body, an annular valve seat portion formed in the valve body, a valve body, and a valve stem for moving the valve body, wherein the valve body is the annular valve seat portion. A disc-shaped valve closing member seated on the valve closing member, and a valve closing member holding collar having an annular brim portion located on the outer periphery of the valve closing member, the lower end portion of the annular flange portion of the valve closing member holding outer collar having the annular shape. An electrically operated valve which is located on the outer periphery of a seat end of a valve seat portion and whose flow rate is adjusted by a gap between a lower end portion of the annular flange portion and a seat end portion of the annular valve seat portion. 3. The motor-operated valve according to claim 1, wherein the seat end portion of the annular valve seat portion has a semicircular cross section. 4. The motor-operated valve according to claim 1, wherein the seat end portion of the annular valve seat portion has a tapered outer peripheral cross-sectional shape. 5. A lower end portion of an annular collar portion of the valve closing member holding collar projects downward from a lower surface of the valve closing member, and
The motor-operated valve according to claim 2, wherein a chamfered corner portion is provided inside.