JP2001090859A - Valve with actuator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce heat transfer of fluid flowing in a valve as small as possible for preventing an actuator loaded no the vale from being influenced by heat, have a heat transfer prevention mechanism provided with predetermined strength, and reduce cost effectively. SOLUTION: In a valve comprising a connector 10 adapted to connect a stem 4 to open/close a body 2 of the valve with an output shaft 12 of an actuator 11 to have the stem 4 driven, fitting grooves 13a and 13b are formed above and below the connector 10 made of materials with low thermal conductivity. Connecting pins 14a and 14b are fixed in the axial direction of each fitting groove. The output shaft 12 and the stem 4 are fitted in the fitting grooves to have each end of them connected to the connecting pins 14a and 14b.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a valve with an actuator, and more particularly to a valve with an actuator applied to opening and closing and controlling a high-temperature fluid such as steam or a low-temperature fluid such as cold water.

[0002]

2. Description of the Related Art When a valve of this type is mounted on a piping line for supplying steam in an air conditioner, for example, when the fluid temperature of the steam exceeds, for example, 180 degrees, the fluid temperature passes through the stem or body of the valve. The heat is transmitted to the inside of the actuator, and this heat causes the internal motors and switches,
The substrate or the like is heated to about 90 degrees.

[0003] When the internal parts are heated to a high temperature in this way, the heat damages or breaks the internal parts and causes a failure, or lubricating oil of a gear train built in the actuator flows out. If it scattered or scattered, the gear train deteriorated, causing a failure. Therefore, Japanese Patent Application Laid-Open No. 8-75025 has been proposed as a conventional example for improving these defects.

This conventional electric valve has a structure in which an output shaft of an electric actuator and a stem of a valve body are connected by a resin joint, and is fitted in a direction crossing the axial direction of the resin joint. Two pins are fitted into the holes, one pin is connected to the split groove of the output shaft of the electric actuator, the other pin is connected to the split groove of the stem of the valve body, and the outer periphery of the resin joint is thermally shrunk. It is a structure covered with a tube.

[0005]

However, the resin joint used for the connection structure of the motor-operated valve is manufactured by resin molding into a hollow cylindrical shape, and then two pin fitting holes are machined in the direction crossing the resin joint. Therefore, the number of processing steps is increased, which is a factor of cost increase. In addition, since the fitting hole of the pin is formed on the cylindrical outer peripheral surface of the resin joint, it is difficult to accurately provide the position of the fitting hole.

Further, since the pin is fitted into the through-hole-shaped fitting hole from the lateral direction, the pin may come out of the fitting hole. Since the shrink tube needs to be coated, this is also one of the causes of cost increase.

SUMMARY OF THE INVENTION The present invention has been developed to solve the conventional problems. It is an object of the present invention to minimize the heat transfer of a fluid flowing through a valve so that an actuator mounted on the valve affects heat. The heat transfer preventing structure has a predetermined strength, and the cost can be effectively reduced.

[0008]

In order to achieve the above object, an invention according to claim 1 is for connecting a stem for opening and closing a valve body of a valve to an output shaft of an actuator for driving the stem. In a valve provided with a connector, fitting grooves are formed above and below a connector formed of a material having poor heat conductivity, connection pins are fixed in the axial direction of each fitting groove, and the output shaft and the stem are connected to each other. An actuator-equipped valve in which each end is connected to a connection pin by fitting into the fitting groove.

In this case, it is preferable that the connector is formed into a cylindrical shape with a resin such as polyphenylene sulfide containing a filler, and a fixing groove for fixing a connecting pin provided in a fitting groove of the connector is provided with an axial center of the resin connector. It is preferable to integrally mold in the direction and omit the processing step.

[0010]

Next, an embodiment of a valve with an actuator according to the present invention will be described with reference to the drawings.
1 and 2, a circular hole 2 is provided inside a metal body 1.
The ball 2 having a is rotatably provided through a pair of resin ball sheets 3. The ball 2 is rotatably provided integrally or separately with a stem 4 (stainless steel in this example) connected thereto. The stem 4 is axially mounted on a shaft cylinder portion 5 of the body 1 via a stem bearing 6 and a thrust washer 7, and further presses a packing 8 with a bush 9 to rotatably seal the stem 4. .

In FIG. 3, reference numeral 10 denotes a connector formed of a material having poor heat conductivity. The connector 10 includes a stem 4 for opening and closing a valve body (ball) 2 of a valve and an actuator for driving the stem 4. 11 is connected to the output shaft 12 of this connector.
Uses an engineering plastic that is polyphenylene sulfide (PPS) filled with a filler such as glass fiber having excellent heat resistance, chemical resistance, and strength. Note that other resins or materials such as metals may be used as long as they have these characteristics, and these are appropriately selected according to the implementation.

The connector 10 is formed integrally with the upper and lower circular fitting grooves 13a and 13b in the axial direction while leaving a central portion of the meat portion. The fitting grooves 13a and 13b have: Fixing grooves 15a and 15b for fixing connecting pins 14a and 14b, which will be described later, are integrally formed in the axial direction of the resin connector 10 at the time of molding, and a processing step is omitted. It is to be noted that the connector 10 may be formed not by molding but by machining.
Since the machining is performed in the direction of the axial center, the cost can be reduced. The connecting pins 14a, 14b are formed by fixing the stainless steel pins 14a, 14b in this embodiment to the fixing grooves 15a, 1b.
5b is tightly fitted to the two connecting pins 1
As shown in FIGS. 5 to 7, 4a and 14b are provided eccentrically in the diameter direction with respect to the axis of the connector 10. Thus, the driving force of the actuator is efficiently transmitted to the stem 4 via the connector 10 by utilizing the moment of the force resulting from the difference in the distance between the actuator output shaft 12 and the center axis of the connecting pin 14b.

Further, as shown in this embodiment, two connecting pins 14 are provided.
By arranging a and b alternately, the overall length of the connector 10 can be shortened, and a compact valve with an actuator can be obtained. In addition to this example, the two connecting pins 14a and 14b may be fixed at positions in the cross direction eccentric by 90 degrees. Furthermore, in this example, the shape of the connecting pins 14a and 14b is cylindrical, but may be rectangular and may be appropriately selected. In order to increase the strength of the connecting pins 14a and 14b, two pins may be provided in each fitting groove or the strength characteristics of the pins may be increased.

At the respective ends of the stem 4 and the output shaft 12, connecting grooves 16, 17 are formed.
Are engaged with the connecting pins 14a and 14b so that the output shaft 12 and the stem 4 are linked by the connector 10. In this example, the slit-like connecting grooves 16 and 17 are provided at the ends of the stem 4 and the output shaft 12, but it is not always necessary to provide the cross-sections of the stem 4 and the output shaft 12 in a cross-section. A connecting groove is provided in a part of the connecting pins 14a, 14b.
May be a hole corresponding to. Thereby, the number of processing steps for the stem and the output shaft can be reduced.

This actuator 11 is electrically driven, pneumatic,
It is a drive device such as a hydraulic or manual gear mechanism. In this example, it is an electric motor type actuator in which internal parts such as a motor, a limit switch, a cable, a printed circuit board, a capacitor, and a gear mechanism are incorporated in a housing and a cover. The actuator is provided with an output shaft 12 driven by a motor (not shown) via a gear mechanism.

1 and 2, reference numeral 18 denotes a body-1.
The bracket 18 has a flange portion 19 provided on the shaft tube portion 5 and a flange portion for fixing the lower portion of the actuator 11.
In the present example, it is made of polyphenylene sulfide (PPS) filled with a filler of a reinforcing material such as glass fiber having excellent heat resistance, chemical resistance, and strength. Although an engineering plastic is used, another resin or a material such as a metal may be used.

The bracket 18 is attached to the flange portion 19 by screwing a bolt 21 into a recessed insert 20, and is fixed to the actuator 11 with a bolt 22. The connector 10 is inserted into the insertion hole 23 formed at the center of the bracket 18. A predetermined space 24 for heat insulation is provided between the insertion hole 23 and the outer diameter of the bracket 18. Is provided.

Next, the operation of the above embodiment will be described.
When a high-temperature fluid such as steam is supplied to the valve, in FIG. 1, this heat is transmitted through the stem 4 and is sequentially transmitted to the upper end of the stem 4, but the heat is shut off by the resin connector 10. As a result, the temperature of the heat transmitted to the output shaft 12 decreases, so that the heat of the high-temperature fluid is not transmitted to the inside of the actuator 11, and the heat which is significantly lower than the fluid heat is transmitted. Will be done. Therefore, there is no possibility that the internal components of the actuator 11, such as the motor, the condenser, and the gear mechanism, are damaged or deteriorated.

Since the output shaft 12 driven by the actuator 11 has the connection groove 17 connected to the connection pin 14b in an engaged state, the connection pin 14a is connected to the connection groove 16 via the resin connector 10. The stem 4 is rotated to open and close and control the ball 2 by the stem 4. Also, the connecting pins 14a, 14b
Is fixed inside the connector 10, so that it is not necessary to take any special measures such as covering the outer periphery of the connector to prevent the connection pins from coming off.

Further, since the bracket 18 is formed of a resin material having poor heat conductivity similarly to the connector 10,
Since the heat of the high-temperature fluid is also insulated by the bracket 18, heat conduction to the actuator 11 is also reduced at this portion.

In the above example, the heat conduction of the high-temperature fluid has been described. However, if the present invention is applied to a valve to which cold water or the like is supplied, the connector 10 prevents the heat conduction due to the cold heat, thereby preventing the actuator and the like from dewing.

[0022]

As is apparent from the above, according to the present invention, the heat transfer of the high temperature fluid of the valve is minimized so that the internal components of the actuator mounted on the valve are not affected by the heat of the fluid. Damage to internal parts,
The durability of the actuator is improved without deterioration.

Further, the heat transfer preventing structure of the connector according to the present invention has a predetermined rotational torque and strength, and
Since the processing steps can be omitted and the manufacturing can be performed with high accuracy as compared with the conventional structure, it is possible to obtain a low cost economical valve with an actuator by reducing the cost.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional front view showing an example of a valve with an actuator according to the present invention.

FIG. 2 is a partially cutaway side view of FIG.

FIG. 3 is an exploded perspective view of a resin connector portion shown in FIG. 1;

FIG. 4 is a front view showing a state where FIG. 3 is connected.

FIG. 5 is a sectional view taken along line AA of FIG. 4;

FIG. 6 is a sectional view taken along line BB of FIG. 4;

FIG. 7 is a sectional view taken along line CC of FIG. 4;

[Description of Signs] 1 Body 4 Stem 10 Connector 11 Actuator 12 Output shaft 13a Fitting groove 13b Fitting groove 14a Connecting pin 14b Connecting pin 15a Fixing groove 15b Fixing groove 16 Connection groove 17 Connection groove

Claims (3)

[Claims] 1. A valve provided with a connector for connecting a stem for opening and closing a valve body of a valve and an output shaft of an actuator for driving the stem. Forming a fitting groove in, the connecting pin is fixed in the axial direction of each fitting groove,
A valve with an actuator, wherein the output shaft and the stem are fitted into the fitting groove and their respective ends are connected to connecting pins. 2. The valve with an actuator according to claim 1, wherein the connector is formed of a resin such as polyphenylene sulfide containing a filler. 3. The valve with an actuator according to claim 1, wherein a fixing groove for fixing the connecting pin provided in the fitting groove of the connector is integrally formed in the axial direction of the resin connector.