JP2006258244A - Electric operated valve - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent damage due to volume expansion at a time of freezing of moisture in a lock nut which is a joining member without increasing working man-hours. <P>SOLUTION: In an embodiment, bypass holes 19a are formed on a lock nut 19 at three sections. The bypass hole 19a is positioned to communicate to a space 40 in the lock nut 19 formed on an inner wall of a ring shape part 19b of a the lock nut 19, a step part 18f of a valve main body 18, an outer edge surface 171d having pointed tip of an opening circumference part 17d of a holder 17, or the like. The bypass hole 19a releases volume expansion at a time of freezing of moisture even if atmospheric temperature of moisture in air intruding the space 40 in the lock nut 19 drops and the moisture freezes, and pressure in the lock nut 19 is reduced. Consequently, damage of the lock nut 19, and damage of pointed edge surface of the opening edge part 17d of the holder 17 or the like can be prevented. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an electric valve for controlling the flow rate of a fluid such as a refrigerant.

  Conventionally, for example, a motor-operated valve is used to control the flow rate of a fluid such as a refrigerant. As an example of such a motor-operated valve, a structure shown in, for example, Patent Document 1 shown in FIG. 4 is used. In this electric valve, a valve shaft 101 connected to a rotating shaft of a motor via a gear or the like is pivotally supported by a bearing 102, and a screw portion of the valve shaft 101 'is screwed to a holder 103. The bearing 102 is fixed to the holder 103. The valve shaft 101 'is connected to the valve body 105 via a pivot bearing 104 or the like. A valve body 106 that houses the valve body 105 is coupled to the holder 103 by a lock nut 107. A bellows 108 is provided in the valve body 106 to prevent fluid from flowing from the valve body 106 to the motor side.

  In addition, this electric valve is provided with a packing 110 between the holder 103 and the valve main body 106. The tip of the holder 103 on the valve body 106 side is formed in an edge shape and serves as a seal portion 111. The packing 110 and the seal part 111 prevent moisture and the like from entering the valve body 106 from the outside.

In this electric valve, the opening of the valve body 105 connected to the valve shaft 101 ′ relative to the valve seat is raised by rotating the motor to rotate the threaded portion of the valve shaft 101 ′, thereby moving the valve shaft 101 ′ up and down. Adjust to control fluid flow.
Japanese Patent Laid-Open No. 11-225466

  In the electric valve of Patent Document 1 described above, the lock nut 107 is used to couple the holder 103 and the valve main body 106. However, under severe use conditions, the lock nut 107, the holder 103, and the valve main body 106 are not connected. Moisture that has entered the gap may freeze when the ambient temperature drops.

  Moisture that has entered the gaps between the lock nut 107 and the holder 103 and the valve body 106 expands in volume when frozen, so that the lock nut 107 is pushed up or the seal portion 111 of the holder 103 is broken. The parts could be damaged.

  As a preventive measure, an adhesive such as Loctite (registered trademark) is applied to the joint between the lock nut 107, the holder 103, and the valve main body 106 to prevent moisture from entering the gap. However, there is a problem that the number of work steps for applying the adhesive increases.

  The present invention has been made in view of the above circumstances, and can prevent breakage due to volume expansion during freezing of moisture in a lock nut as a coupling member even under severe usage conditions without increasing the number of work steps. An object of the present invention is to provide a motorized valve that can be used.

In order to achieve the above object, the motor-operated valve of the present invention includes:
A holder fixed to the motor, a valve main body connected to the holder via a lock nut, and disposed in the valve chamber so as to face an opening of a valve seat provided in the valve main body, and by the operation of the motor A valve body for operating opening and closing of the opening,
The lock nut is formed with a through hole communicating with a space generated between the lock nut and the holder.

  In addition, the holder may be provided with an edge seal having a sharp tip that contacts the valve body, and the through hole may be formed at a position facing the edge seal.

  Further, a plurality of the through holes may be provided.

  The through hole may be filled with an elastic material such as silicon rubber.

  Further, a bellows having one end fixed to the valve body and the other end fixed to the valve body may be provided.

  ADVANTAGE OF THE INVENTION According to this invention, the motor operated valve which can prevent the damage by the volume expansion at the time of the freezing of the water | moisture content in the lock nut which is a coupling member can be provided, without increasing work man-hours.

  An electric valve according to an embodiment of the present invention will be described below with reference to the drawings. The motor-operated valve 10 is used as a control valve for controlling the flow rate of a fluid such as a refrigerant in a refrigeration / air conditioning apparatus, for example. The electric valve 10 transmits the output of the motor 30 to the valve body through a gear or the like.

  As shown in FIGS. 1 to 3, the motor-operated valve 10 includes a valve shaft 11, a valve body 12 coupled to the valve shaft 11, a sphere 13 for coupling the valve shaft 11 and the valve body 12, and a bush 14, a bellows 15, an output bearing 16 that is a bearing for the valve shaft 11, a holder 17 that is fixed to the motor and holds the valve shaft 11, a valve body 18 that houses the valve body 12, and a valve body 18 An integrally formed valve seat 18 a and a lock nut 19 that connects the holder 17 and the valve body 18 are provided.

  The valve shaft 11 is an output shaft for transmitting the rotational output of the motor 30 and moving the valve body 12 up and down. The valve shaft 11 includes a first valve shaft 11a located on the motor side and a second valve shaft 11b located on the valve body 12 side. A minus driver-shaped projection 111a is formed at the lower end of the first valve shaft 11a, and a minus driver groove-shaped recess 111b is formed at the upper end of the second valve shaft 11b. The first valve shaft 11a and the second valve shaft 11b are connected by fitting the convex portion 111a to the concave portion 111b. The first valve shaft 11a is connected to the rotating shaft of the motor 30 built in the motor case via a pinion, a gear, and the like. The first valve shaft 11 a is pivotally supported by the output bearing 16. The output bearing 16 is provided in the motor case of the motor 30. A male screw portion 112b is formed on the outer periphery of the second valve shaft 11b. The male thread 112b of the second valve stem 11b is screwed with the first female thread 17a formed at the center of the holder 17, so that the second valve stem 11b can rotate to the holder 17 in the axial direction. Is held movable.

  The valve body 12 is for moving up and down so as to come into contact with and separate from the valve seat 18a and adjust the opening degree of the valve seat 18a. The valve body 12 is disposed in the valve chamber so as to face the valve hole 181a which is an opening of the valve seat 18a. The valve body 12 includes a first valve body 12a on the valve shaft 11 side and a second valve body 12b on the valve seat 18a side. The first valve body 12a is press-fitted and fixed to the second valve body 12b, for example. A convex locking portion 122 a is formed on the outer periphery of the first valve body 12 a, and this locking portion 122 a is provided for fixing the bellows 15. A recess 123a is formed at the upper end of the first valve body 12a, and the convex bush 14 is press-fitted into the recess 123a. The tip of the second valve body 12b on the valve seat 18a side has a pointed shape.

  The spherical body 13 is interposed between the lower end of the second valve shaft 11b and the bush 14 as a pivot bearing. The spherical body 13 is formed using, for example, a stainless material, and is welded to the lower end of the second valve shaft 11b, for example, by spot welding. Further, the spherical body 13 is disposed so as to be rotatable in contact with a recess 14a of the bush 14 press-fitted into the upper end of the first valve body 12a.

  The bellows 15 has stretchability and airtightness, and has a function of preventing the refrigerant flowing into the valve body 18 from entering the motor 30 side. The bellows 15 is fixed by soldering to a washer 21 whose upper end is caulked and fixed to an end in the valve body 18, and its lower end is fixed to a locking portion 122 a of the first valve body 12 a by soldering.

  The valve body 18 has a cylindrical shape for housing the valve body 12. The valve main body 18 has a first passage 18b connected to the lower side of the side surface, and a second passage 18c communicating with the first passage 18b and connected to the bottom surface. The first passage 18b and the second passage 18c are each connected to a refrigerant pipe. A valve seat 18a is formed at a connection portion between the first passage 18b and the second passage 18c and a connection portion between the valve body 18 and the second passage 18c. The valve seat 18 a has a valve hole 181 a communicating with the second passage 18 c on the bottom surface of the valve body 18.

  The output bearing 16 is fixed to the holder 17 by screwing a male thread portion 16 a formed on the outer periphery of the output bearing 16 with a second female thread portion 17 b formed above the holder 17. Between the bottom surface of the output bearing 16 and the holder 17, a washer 22 that is a stopper of the second valve shaft 11b is provided.

  The lock nut 19 is coupled to the valve body 18 and the holder 17 by screwing into a male screw portion 18 d formed on the upper side of the valve body 18. An upper end of the valve body 18 is formed with an end 18e having a smaller diameter than the outer diameter, and a recess 17c is formed at the lower end of the holder 17. The valve body 18 and the holder 17 are connected in a state where the end 18 e of the valve body 18 is fitted in the recess 17 c of the holder 17. A rubber packing 23 is sandwiched between the tip of the end 18 e of the valve body 18 and the bottom of the recess 17 c of the holder 17. The rubber packing 23 seals between the valve body 18 and the holder 17. Moreover, the opening peripheral part 17d of the lower end of the holder 17 is formed in the edge shape where the front-end | tip sharpened acutely, and comprises the edge seal | sticker. The opening peripheral edge portion 17d of the holder 17 formed in an edge shape with a sharp tip at its tip is brought into contact with and pressed against the stepped portion 18f of the valve body 18 by tightening the lock nut 19, thereby sealing the seal. It is secured. The rubber packing 23 and the edge-like portion sharpened at the tip of the opening peripheral edge portion 17d constituting the seal portion prevent moisture and the like from entering the valve body 18 from the outside.

  The lock nut 19 has relief holes 19a formed at, for example, three places. The escape hole 19a is a through hole formed in the side surface portion 19b of the lock nut 19 and penetrating from the inner wall to the outer wall of the ring-shaped portion 19b. The three relief holes 19a are formed at equal angular intervals at positions where the central angles of the ring-shaped portions 19b of the lock nut 19 form 120 degrees. The relief hole 19a is a lock formed by the outer edge surface 171d of the inner wall of the ring-shaped portion 19b of the lock nut 19, the stepped portion 18f of the valve body 18 and the edge surface of the opening peripheral edge portion 17d of the holder 17 that is pointed. It is located so as to communicate with the space 40 in the nut 19. Further, the escape hole 19a is arranged to face the edge surface 171d so as to face a portion of the space 40 having a large volume.

  The escape hole 19a allows the volume of the lock nut 19 and the holder 17 generated by freezing to escape due to the volume expansion at the time of water freezing even when the water entering the space 40 in the lock nut 19 freezes due to a decrease in ambient temperature. Since the pressure on the edge surface 171d can be reduced, it is possible to prevent the lock nut 19 from being damaged and the opening peripheral edge portion 17d of the holder 17 from being damaged.

  In the electric valve 10, when the motor 30 rotates in the forward / reverse direction, for example, the forward direction, the valve shaft 11 rotates, for example, in the counterclockwise direction. By rotating the male threaded portion 112b of the valve shaft 11, the valve shaft 11 moves upward, for example, and the valve body 12 to be connected also moves upward. When the pointed tip of the second valve body 12b on the lower side of the valve body 12 is separated from the valve seat 18a, the flow rate of the refrigerant flowing through the first passage 18b and the second passage 18c increases. On the other hand, when the motor 30 rotates in the reverse direction, for example, the valve shaft 11 rotates in the clockwise direction. The valve shaft 11 moves downward, and the connected valve body 12 also moves downward. As the pointed tip of the second valve body 12b approaches the valve seat 18a, the flow rate of the refrigerant flowing through the first passage 18b and the second passage 18c decreases. In this way, the flow rate of the refrigerant is controlled.

  As described above, in the electric valve according to the present embodiment, even when the moisture that has entered the space 40 in the lock nut 19 freezes, the volume expansion due to moisture freezing can be released by the escape hole 19a. Damage to parts such as the lock nut 19 during moisture freezing can be prevented. Therefore, it is possible to prevent damage to parts such as the lock nut 19 during moisture freezing without requiring a man-hour such as applying an adhesive to the joint between the lock nut 19 and the valve body 18.

  The present invention has been described with reference to the embodiment. However, the present invention is not limited to the above embodiment, and various modifications can be made. For example, the escape hole 19a of the lock nut 19 is filled with an elastic material such as silicon rubber and sealed, and the elastic material contracts in the escape hole 19a when the volume expansion due to moisture freezing in the lock nut 19 occurs. You may do it. By sealing the escape hole 19 a with an elastic material, it is possible to prevent moisture from entering the lock nut 19.

  Further, in the lock nut 19 of the present embodiment, the three escape holes 19a are formed at equiangular intervals. However, the number of the escape holes may be less than three, for example, one, or four or more. May be. Moreover, the relief hole 19a should just be the shape which penetrates the inner wall and outer wall of the ring-shaped part 19b of the lock nut 19, and the shape of a hole is not restricted to a round hole, It is not restricted to a linear hole.

  In the present embodiment, the example in which the valve seat 18a is integrally formed with the valve body 18 has been described. However, the valve seat may be provided as a separate body.

  Moreover, although this embodiment demonstrated the example which comprises the valve body 12 by the 1st valve body 12a and the 2nd valve body 12b, you may make it comprise a valve body by one member.

  Further, in the present embodiment, the second valve shaft 11b is attached to the holder by the male screw portion 112b of the second valve shaft 11b being screwed with the first female screw portion 17a formed at the center of the holder 17. Although an example in which the valve shaft is rotatably held in the axial direction has been described in FIG. 17, the mechanism that enables the valve shaft to move in the axial direction is not limited thereto.

It is a partial sectional view showing a schematic structure of an electric valve concerning an embodiment of the present invention. It is sectional drawing showing the principal part of the motor operated valve shown in FIG. FIG. 3 is a partially enlarged view of the electric valve shown in FIG. 2. It is a partial cross section showing the schematic structure of the principal part of the conventional motor operated valve.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Motorized valve 11 Valve shaft 11a 1st valve shaft 11b 2nd valve shaft 12 Valve body 12a 1st valve body 12b 2nd valve body 16 Output bearing 17 Holder 17d Opening peripheral part 171d Edge surface 18 Valve main body 18a Valve Seat 18b First passage 18c Second passage 181a Valve hole 18f Stepped portion 19 Lock nut 19a Relief hole 19b Side surface portion 30 Motor 40 Space

Claims (5)

A holder fixed to the motor, a valve main body connected to the holder via a lock nut, and disposed in the valve chamber so as to face an opening of a valve seat provided in the valve main body, and by the operation of the motor A valve body for operating opening and closing of the opening,
The electric valve according to claim 1, wherein the lock nut is formed with a through hole communicating with a space generated between the lock nut and the holder.   2. The motor-operated valve according to claim 1, wherein the holder is provided with an edge seal having a sharp tip that contacts the valve body, and the through hole is formed at a position facing the edge seal. .   The electrically operated valve according to claim 1 or 2, wherein a plurality of the through holes are provided.   The motor-operated valve according to any one of claims 1 to 3, wherein the through hole is filled with an elastic material such as silicon rubber.   The motor-operated valve according to any one of claims 1 to 4, further comprising a bellows having one end fixed to the valve body and the other end fixed to the valve body.

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