JP2020148344A - Motor-operated valve - Google Patents

Abstract

To provide a motor-operated valve that can restrain a decrease in a flow rate while being further reduced in size and cost.SOLUTION: A motor-operated valve comprises: a valve body 5 in which a valve chest 7 is defined; a valve seat member 8 comprising a valve seat 8a with a valve port 9 opened in the valve chest 7, and provided in a bottom part 8c of the valve body 5; a lateral pipe member 11 provided so as to communicate with a side part of the valve chest 7; a lower pipe member 12 provided so as to communicate with the valve chest 7 via the valve port; a valve element 20 arranged in the valve chest 7 so as to be capable of being elevated/lowered; and an elevating/lowering driving part for elevating/lowering the valve element with respect to the valve seat 8a. The inner diameter of the lateral pipe member 11 opened in the valve chest 7 is larger than the inner diameter of the lower pipe member 12. The inner diameter of the lateral pipe member 11 opened in the valve chest 7 is 1.1 or more times as large as the bore of the valve port 9.SELECTED DRAWING: Figure 1

Description

The present invention relates to an electric valve, for example, an electric valve used in a heat pump type heating / cooling system or the like.

A conventional example of this type of motorized valve is shown in FIG. In the illustrated conventional electric valve 1', a valve chamber 7 is defined inside, and a valve body 5 having a first opening 11a and a second opening 12a formed in a side portion and a bottom portion and a valve chamber 7 are opened. A valve seat member 8 having a valve seat 8a with a valve port 9 and fixed to a second opening 12a of the valve body 5, a valve body 20 arranged so as to be able to move up and down in a valve chamber 7, and a valve body 20 are valved. A stepping motor 50 as an elevating drive unit for elevating and lowering the seat 8a is provided.

Specifically, the electric valve 1'of the conventional example is defined by a valve body 5 having a tubular base body 6 with a bottom made of sheet metal, a can 58 fixed to the valve body 5, a valve body 5 and a can 58. A support member 19 fixedly arranged in the valve body 5 in the internal space, a valve body 20 supported by the support member 19 and arranged so as to be able to move up and down in the internal space, and a valve body 5 for raising and lowering the valve body 20. It is provided with a stepping motor (elevating drive unit) 50 mounted above the above.

In the tubular substrate 6 of the valve body 5, a valve chamber 7 is defined inside, and a lateral first opening 11a that opens into the valve chamber 7 is formed on the side thereof, and the valve chamber 7 is formed at the bottom thereof. A vertically oriented second opening 12a that opens is formed. A stepped valve seat member 8 having a valve seat 8a with a vertically oriented valve opening 9 that opens into the valve chamber 7 is fixed to the second opening 12a formed at the bottom of the tubular base 6 of the valve body 5. ing. A horizontal pipe member 11 as a conduit joint is laterally attached to the first opening 11a formed on the side portion of the tubular substrate 6, and is larger than the valve opening 9 formed on the bottom 8c side of the valve seat member 8. A lower pipe member 12 as a conduit joint communicating with the valve opening 9 of the valve seat member 8 is vertically attached to the connection port 12b having a diameter.

The bottom portion 8c of the valve seat member 8 is fitted into the second opening 12a and fixed to the bottom portion of the tubular base body 6, and the lower pipe member 12 is fitted into the connection port 12b formed on the bottom portion 8c side. It is installed. Further, an inclined surface 8b connected to the valve seat 8a is formed at the upper end portion of the valve seat member 8, and the upper end portion 8d of the inclined surface 8b is slightly smaller than the center of the horizontal pipe member 11 attached to the first opening 11a. The valve seat member 8 and the horizontal pipe member 11 are arranged so as to be located below.

A stepped tubular base 13 whose diameter is reduced upward is attached to the upper opening of the tubular substrate 6 of the valve body 5. The lower end of the cylindrical can 58 having a ceiling is joined to the upper end of the tubular base 13 by welding or the like. Further, the support member 19 has a tubular holding member 14 with a partition wall 14c and a bearing member 15 with a female screw 15i, and the tubular holding member 14 is fixed to the inside of the tubular base 13 by press fitting or the like to form a tubular shape. A tubular bearing member 15 having a female screw 15i screwed below the inner peripheral surface is fixed to the upper portion of the holding member 14 by caulking or the like. A protrusion 15a is formed on the center side of the lower surface of the bearing member 15, and a female screw 15i is also screwed into the protrusion 15a. Further, a spring chamber 14a is defined between the partition wall 14c of the tubular holding member 14 and the bearing member 15, and the valve opening spring 25 for urging the valve body 20 in the valve opening direction is housed in the spring chamber 14a. There is.

The valve body 20 is formed of a tubular body in which a pressure equalizing passage 32 along the elevating direction (vertical direction) of the valve body 20 is formed in the central portion thereof, and the upper portion of the valve body 20 is the tubular holding member 14. It is slidably fitted in the valve body guide hole 14b below the partition wall 14c, and the lower part of the valve body 20 is from the tubular holding member 14 (valve body guide hole 14b) to the valve seat member 8 (of the valve body 20). It protrudes toward the valve port 9). The valve body 20 has an upper cylindrical portion 20b having a constant inner diameter and a skirt portion 20c whose inner diameter continuously expands toward the valve opening 9 of the valve seat member 8 from above, and the inner circumference of the upper cylindrical portion 20b. The surface is continuously connected to the inner peripheral surface of the skirt portion 20c. The center hole of the upper cylindrical portion 20b is a fitting hole 20d into which the small diameter lower portion 23c of the thrust transmission member 23 is fitted and fixed, and the lower end portion of the skirt portion 20c is separated from the valve seat 8a of the valve seat member 8. The valve body portion 20a has a substantially truncated cone shape that opens and closes the valve port 9.

On the other hand, the stepping motor 50 is rotatably arranged inside the can 58 with the stator 55 including the yoke 51, the bobbin 52, the coil 53, the resin mold cover 54, and the rotor support member 56. It has a rotor 57 fixed to the inside of the upper portion. The stator 55 is externally fitted and fixed to the can 58. Further, on the inner peripheral side of the rotor 57, a sun gear 41 integrally formed with the rotor support member 56, and a fixed ring gear 47 fixed to the upper end of the tubular body 43 fixed to the upper part of the tubular holding member 14. , A planetary gear 42 that is arranged between the sun gear 41 and the fixed ring gear 47 and meshes with each other, a carrier 44 that rotatably supports the planetary gear 42, and a bottomed ring that meshes with the planetary gear 42 from the outside. A mysterious planetary gear type speed reduction mechanism 40 including an output gear 45 and an output shaft 46 whose upper portion is fixed to a hole formed in the bottom of the output gear 45 by press fitting or the like is provided. Here, the number of teeth of the fixed ring gear 47 is set to be different from the number of teeth of the output gear 45.

A hole is formed in the central portion of the upper part of the output shaft 46, and the lower portion of the support shaft 49 through which the central portion of the sun gear 41 (rotor support member 56) and the carrier 44 is inserted is inserted into the hole. The upper portion of the support shaft 49 has an outer diameter substantially the same as the inner diameter of the can 58, and is formed in a hole formed in the central portion of the support member 48 arranged inscribed in the can 58 on the upper side of the rotor support member 56. It has been inserted. The rotor 57 itself is prevented from moving up and down inside the can 58 by a support member 48 or the like, and the positional relationship with the stator 55 externally fitted and fixed to the can 58 is always maintained constant.

The lower portion of the output shaft 46 of the speed reduction mechanism 40 is rotatably fitted into the upper portion of the tubular bearing member 15 constituting the support member 19 that supports the output shaft 46 and the like, and the lower portion of the output shaft 46 is the lower portion thereof. A slit-shaped fitting portion 46a extending laterally so as to pass through the center is formed. A plate-shaped portion 17c is projected from the upper end of the rotary elevating shaft 17 into which a male screw 17a screwed with a female screw 15i screwed below the inner peripheral surface of the bearing member 15 is screwed, and the plate-shaped portion 17c has a slit shape. It is slidably fitted to the fitting portion 46a of the above. When the output shaft 46 rotates in accordance with the rotation of the rotor 57, the rotation of the output shaft 46 is transmitted to the rotary elevating shaft 17, and the rotary elevating shaft 17 is fed by the female screw 15i of the bearing member 15 and the male screw 17a of the rotary elevating shaft 17. Goes up and down while rotating.

Below the rotary elevating shaft 17, a stepped tubular thrust transmitting member 23 is arranged in which the downward thrust of the rotary elevating shaft 17 is transmitted via the balls 18 and the ball receiving seat 16. By interposing the ball 18 between the rotary lift shaft 17 and the thrust transmission member 23, for example, even if the rotary lift shaft 17 descends while rotating, the rotary lift shaft 17 moves downward to the thrust transmission member 23. Only thrust is transmitted, not rotational force.

The thrust transmission member 23 is an intermediate body portion slidably inserted into a hole formed in a large-diameter upper portion 23a in which the ball receiving seat 16 is fitted on the inner circumference and a partition wall 14c of the tubular holding member 14 from above. It is composed of 23b, a small diameter lower part 23c having a diameter smaller than that of the intermediate body portion 23b, and inside the vertical through hole 32d forming the upper part of the pressure equalizing passage 32 formed in the valve body 20, and a back described later. A plurality of lateral holes 32e that open into the pressure chamber 30 are formed. The upper end opening of the through hole 32d is closed by the ball receiving seat 16.

As described above, the small diameter lower portion 23c of the thrust transmission member 23 is fitted and fixed to the fitting hole 20d of the upper cylindrical portion 20d of the valve body 20 by press fitting or the like, and the valve body 20 and the thrust transmission member 23 are integrally formed. It is raised and lowered. A pressing member 24 is sandwiched and fixed between the upper end surface of the valve body 20 and the lower end step portion of the intermediate body portion 23b of the thrust transmission member 23 when the small diameter lower portion 23c is press-fitted. A sealing member 38 such as an O-ring is mounted between the annular groove formed at the upper end of the valve body 20 and the valve body guide hole 14b.

Further, in the spring chamber 14a above the partition wall 14c of the tubular holding member 14, a valve opening spring 25 made of a compression coil spring is arranged in a state where the lower end thereof is in contact with the partition wall 14c, and the valve opening is formed. In order to transmit the urging force (pulling force) of the spring 25 to the valve body 20 via the thrust transmitting member 23, a pulling spring receiving body 28 having flange-shaped hook portions 28a and 28b is arranged vertically. The upper hooking portion 28a of the pulling spring receiving body 28 is placed on the upper portion of the valve opening spring 25, and the lower hooking portion 28b is hooked on the lower end step portion of the large diameter upper portion 23a of the thrust transmission member 23. Further, the tubular holding member 14 is formed with a communication hole 14d that communicates between the spring chamber 14a and the inside of the can 58.

Therefore, when the rotor 57 of the motor 50 is rotationally driven in one direction, the rotation of the rotor 57 is decelerated and transmitted to the rotary elevating shaft 17 via the output shaft 46 of the reduction mechanism 40, and rotates with the female screw 15i of the bearing member 15. The rotary lifting shaft 17 is lowered while rotating by the screw feed by the male screw 17a of the lifting shaft 17, and the thrust transmitting member 23 and the valve body 20 are pushed down against the urging force of the valve opening spring 25 by the thrust of the rotary lifting shaft 17. Finally, the valve body portion 20a formed of the lower end portion of the skirt portion 20c of the valve body 20 is seated on the valve seat 8a, and the valve opening 9 is closed. On the other hand, when the rotor 57 of the motor 50 is rotationally driven in the other direction, the rotation of the rotor 57 is decelerated and transmitted to the rotary elevating shaft 17 via the output shaft 46 of the speed reduction mechanism 40, and is transmitted by the female screw 15i and the male screw 17a. The rotary elevating shaft 17 is raised while rotating by screw feeding, for example, the thrust transmission member 23 and the valve body 20 are pulled up by the urging force of the valve opening spring 25, and the valve body portion 20a is separated from the valve seat 8a and the valve opening. 9 is opened (state shown in FIG. 4).

Further, a back pressure chamber 30 is defined above the valve body 20 between the pressing member 24 and the partition wall 14c of the tubular holding member 14. Inside the valve body 20, a thick passage consisting of an inner peripheral surface of a skirt portion 20c whose lower end opens toward the valve opening 9 from below in order to communicate the lower end portion of the valve body 20 and the back pressure chamber 30. A pressure equalizing passage 32 having a narrow passage portion 32c (fitting hole 20d) composed of a portion 32b and an inner peripheral surface of the upper cylindrical portion 20b is formed, and the narrow passage portion 32c forms a through hole 32d of the thrust transmission member 23 and a through hole 32d. It communicates with the back pressure chamber 30 through the lateral hole 32e. Here, the pushing-down force acting on the valve body 20 (force acting in the valve closing direction) and the pushing-up force acting on the valve body 20 (force acting in the valve opening direction) in the valve closed state are balanced (the differential pressure is canceled). Therefore, the diameter of the back pressure chamber 30 and the diameter of the valve opening 9 are set to be substantially the same.

Further, in the motorized valve 1'of the conventional example, when the rotor 57 of the motor 50 is rotated in the other direction to open the valve port 9, the fluid (refrigerant) is connected to the first flow direction (first opening 11a). A refrigerant (gas) composed of gas, which is flowed in both directions from the horizontal pipe member 11 toward the lower pipe member 12 connected to the valve seat member 8 of the second opening 12a and vice versa. When the refrigerant) is flowed in the first flow direction, the skirt portion 20c (the portion whose inner diameter changes along the elevating direction) provided on the valve body 20 reduces the abnormal noise generated in the motorized valve 1'. (See Patent Document 1 below).

Japanese Unexamined Patent Publication No. 2015-09432

By the way, in the conventional motorized valve 1'shown in FIG. 4 described above, the pipe diameter (inner diameter and outer diameter) of the horizontal pipe member 11 connected to the side portion of the valve body 5 is considered from the viewpoint of ease of construction and cost. The diameter) and the pipe diameter (inner diameter and outer diameter) of the lower pipe member 12 connected to the bottom portion 8c of the valve seat member 8 are the same. Further, in order to secure the flow rate, the diameter of the valve port 9 is set to be substantially the same diameter (φA) as the inner diameter of the horizontal pipe member 11 and the inner diameter of the lower pipe member 12. Further, here, the inner diameter φC of the tubular base 6 of the valve body 5 is set to be about twice the diameter φA of the valve opening 9, but in recent years, the capacity of the motorized valve 1'has not been reduced. Further, it is desired to reduce the size and cost.

However, for example, while maintaining the capacity of the electric valve, that is, maintaining the inner diameters of the horizontal pipe member and the lower pipe member, and the diameter of the valve opening, the valve body (cylindrical base) is miniaturized (for example). It has been confirmed by the present inventors that when the pipe diameter of the tubular substrate is reduced), the flow velocity in the valve chamber becomes faster and the flow rate loss becomes larger, so that the flow rate decreases.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an electric valve capable of suppressing a decrease in flow rate while further reducing the size and cost. is there.

In order to solve the above-mentioned problems, the electric valve according to the present invention has a valve body in which a valve chamber is defined inside and a valve seat with a valve opening that opens into the valve chamber. A valve seat provided at the bottom, a horizontal pipe member provided so as to communicate with the side portion of the valve chamber, and a lower pipe member provided so as to communicate with the valve chamber via the valve opening. The inner diameter of the lateral pipe member opened in the valve chamber is the inner diameter of the lateral pipe member, which includes a valve body arranged so as to be able to move up and down in the valve chamber and an elevating drive unit for raising and lowering the valve body with respect to the valve seat. It is characterized by being larger than the inner diameter of the lower pipe member.

In a preferred embodiment, the inner diameter of the lateral pipe member opened in the valve chamber is 1.1 times or more the diameter of the valve opening.

According to the present invention, of the horizontal pipe members connected to the first opening formed on the side portion of the valve body so as to communicate with the valve chamber, the portion opening to the valve chamber has a larger inner diameter than the other portions. Since it is a pipe expansion part, even if the valve body is miniaturized, the flow velocity in the valve chamber becomes slow when the fluid flows in the first flow direction or the second flow direction (particularly, the first flow direction). Since the flow rate loss is small, it is possible to suppress the decrease in the flow rate.

The vertical sectional view which shows one Embodiment of the electric valve which concerns on this invention. FIG. 1 is a cross-sectional view taken along the line UU in FIG. The graph which shows the change of the flow rate with respect to the inner diameter of the expansion part of the lateral pipe member of the electric valve shown in FIG. The vertical sectional view which shows the electric valve of a conventional structure.

Hereinafter, embodiments of the motorized valve according to the present invention will be described with reference to the drawings.

FIG. 1 is a vertical sectional view showing an embodiment of an electric valve according to the present invention, and FIG. 2 is a sectional view taken along the line UU of FIG. In FIG. 2, the valve body is omitted.

The motorized valve 1 of the illustrated embodiment is used as an expansion valve in, for example, a heat pump type heating / cooling system, in which a fluid (refrigerant) flows in both directions (a second flow direction opposite to the first flow direction) and at least. It is a bidirectional flow type motorized valve that corresponds to a flow path in which a large flow rate flows in one direction.

The electric valve 1 of the present embodiment has a valve body 5 having a tubular base body 6 made of sheet metal, a can 58 fixed to the valve body 5, and a valve body, similarly to the conventional electric valve 1'shown in FIG. A support member 19 fixedly arranged in the valve body 5 in the internal space defined by the 5 and the can 58, a valve body 20 supported by the support member 19 and arranged so as to be able to move up and down in the internal space, and a valve body 20. It is provided with a stepping motor (elevating drive unit) 50 mounted above the valve body 5 so as to raise and lower the valve body 5.

Here, in the motorized valve 1 of the present embodiment, the can 58 fixed to the valve body 5, the support member 19 (cylindrical holding member 14 with partition wall 14c and bearing member 15 with female screw 15i), and the valve chamber 7 of the valve body 5 A valve body 20 arranged so as to be able to move up and down, a stepping motor 50 (including a mysterious planetary gear type reduction mechanism 40) for raising and lowering the valve body 20 with respect to the valve seat 8a of the valve seat member 8, and the valve body 20. The configuration of the rotary elevating shaft 17 and the thrust transmission member 23, etc., interposed between the stepping motor 50 and the like is shown in FIG. 4 (except that the lower end portion of the tubular holding member 14 of the support member 19 is slightly shortened). It is almost the same as the electric valve 1'of the conventional example shown in. Therefore, the portion having the same function as that of the conventional motorized valve 1'shown in FIG. 4 is designated by the same reference numerals and detailed description thereof will be omitted. The configuration of the valve body 5 (cylindrical base 6) and the horizontal pipe member 11 connected to the valve body 5, which is a feature of the present invention, will be described in detail.

In the electric valve 1 of the present embodiment, the tubular substrate 6 constituting the valve body 5 is formed of a cylindrical body having the same diameter along the axis (center line) O direction (that is, the electric valve of the conventional example. Unlike 1', the tubular substrate 6 does not have a bottom), and a valve chamber 7 composed of a cylindrical void is defined inside the tubular substrate 6), and a laterally oriented valve chamber 7 opens to the valve chamber 7 on its side. One opening 11a is formed. A stepped cylindrical valve seat member 8 having a valve seat 8a with a vertically oriented valve opening 9 that opens into the valve chamber 7 is fixed to the lower end opening (second opening 12a) of the tubular base 6 of the valve body 5. Has been done. A horizontal pipe member 11 as a conduit joint communicating with the valve chamber 7 is laterally attached to the first opening 11a formed on the side portion of the tubular base 6 by brazing or the like, and the bottom portion 8c side of the valve seat member 8 is attached. A lower pipe member 12 as a conduit joint communicating with the valve port 9 of the valve seat member 8 is vertically attached to the connection port 12b having a diameter larger than that of the valve port 9 formed in the valve seat member 8 by brazing or the like.

More specifically, the valve seat member 8 is made of a metal such as SUS, and has a small diameter upper portion 8A provided with the valve seat 8a and a valve opening 9 and a large diameter lower portion 8B provided with the connection port 12b. The lower end portion (second opening 12a) of the cylindrical base 6 made of a cylindrical body is joined to the outer peripheral portion (the flange-shaped portion provided in) of the large-diameter lower portion 8B by butt welding or the like, and the large-diameter lower portion thereof. The lower pipe member 12 is fitted and attached to the connection port 12b formed in 8B. Further, an inclined surface 8b connected to the valve seat 8a is formed at the upper end of the small diameter upper portion 8A of the valve seat member 8, and the upper end 8d of the inclined surface 8b is attached to the first opening 11a of the horizontal pipe member 11. The valve seat member 8 and the horizontal pipe member 11 are arranged so as to be located slightly below the center.

In the conventional electric valve 1'shown in FIG. 4, the inner diameter φC of the tubular base 6 is about twice the diameter φA of the valve opening 9, but in the electric valve 1 of this example, the tubular base 6 The inner diameter φC of the valve port 9 is about 1.7 times the diameter φA of the valve port 9, which makes it possible to reduce the size and weight of the valve body 5 (cylindrical base body 6). Further, since the tubular substrate 6 is formed of cylindrical bodies having the same diameter along the axis (center line) O direction, the processing (manufacturing) cost thereof can be suppressed.

The outer diameter of the tubular base 13 (for example, made of metal such as SUS) attached to the upper opening of the tubular base 6 of the valve body 5 is also changed according to the shape change of the tubular base 6. It is smaller than the motorized valve 1'in the example, and this also makes it possible to reduce the size and weight.

Further, in the conventional motorized valve 1'shown in FIG. 4, the diameter of the first opening 11a formed on the side of the valve body 5 (cylindrical base 6) and the bottom 8c side of the valve seat member 8 are formed. Although the diameter of the connection port 12b is the same as that of the connection port 12b, in the motorized valve 1 of this example, the diameter of the first opening 11a is made larger than the diameter of the connection port 12b, and one end of the horizontal pipe member 11 (first). The end portion on the side connected to the opening 11a and opening to the valve chamber 7 (the portion having a predetermined length) is expanded by pipe expansion processing or the like (tube expansion portion 11B). Also in this example, from the viewpoint of ease of construction, cost, and the like, the pipe diameter (inner diameter and outer diameter) and the lower pipe member 12 of the portion (general portion 11A) other than the pipe expansion portion 11B of the horizontal pipe member 11 The diameter of the valve port 9 is approximately the same as the inner diameter of the general portion 11A of the horizontal pipe member 11 and the inner diameter of the lower pipe member 12 in order to secure the flow rate. It has the same diameter (φA). In the illustrated example, the inner diameter φB of the pipe expansion portion 11B in the horizontal pipe member 11 is about 1.3 times the inner diameter φA of the general portion 11A.

Even in the electric valve 1 of the present embodiment having such a configuration, when the rotor 57 of the motor 50 is rotationally driven in one direction, the rotation of the rotor 57 is decelerated to the rotary elevating shaft 17 via the output shaft 46 of the reduction mechanism 40. The rotary elevating shaft 17 is lowered while rotating by screw feeding by the female screw 15i of the bearing member 15 and the male screw 17a of the rotary elevating shaft 17, and the thrust transmitting member 23 and the valve body 20 are lowered by the thrust of the rotary elevating shaft 17. Is pushed down against the urging force of the valve opening spring 25, and finally the valve body portion 20a formed of the lower end portion of the skirt portion 20c of the valve body 20 is seated on the valve seat 8a and the valve opening 9 is closed. On the other hand, when the rotor 57 of the motor 50 is rotationally driven in the other direction, the rotation of the rotor 57 is decelerated and transmitted to the rotary elevating shaft 17 via the output shaft 46 of the speed reduction mechanism 40, and is transmitted by the female screw 15i and the male screw 17a. The rotary elevating shaft 17 is raised while rotating by screw feeding, for example, the thrust transmission member 23 and the valve body 20 are pulled up by the urging force of the valve opening spring 25, and the valve body portion 20a is separated from the valve seat 8a and the valve opening. 9 is opened (state shown in FIG. 1).

Further, when the rotor 57 of the motor 50 is rotated in the other direction to open the valve port 9, the fluid (refrigerant) flows in the first flow direction (from the horizontal pipe member 11 connected to the first opening 11a to the second opening 12a). (Flow direction toward the lower pipe member 12 connected to the valve seat member 8) and the opposite second flow direction, but in the motorized valve 1 of the present embodiment, as described above, the valve chamber Of the horizontal pipe member 11 connected to the first opening 11a formed on the side portion of the valve body 5 so as to communicate with 7, the portion opening to the valve chamber 7 has an inner diameter larger than that of the other portion (general portion 11A). Is a large pipe expanding portion 11B (in other words, the inner diameter φB of the portion opening to the valve chamber 7 (diameter expanding portion 11B) is larger than the inner diameter φA of the other portion (general portion 11B)). Even when the valve body 5 is miniaturized, when the fluid flows in the first flow direction or the second flow direction (particularly, the first flow direction), the flow velocity in the valve chamber 7 becomes slow and the flow rate loss becomes small. Therefore, it is possible to suppress a decrease in the flow rate.

In particular, when the inner diameter φB of the pipe expansion portion 11B in the horizontal pipe member 11 is 1.1 times or more the diameter φA of the valve port 9, the valve body 5 is downsized (specifically, the valve body 5). Even when the pipe diameter of the tubular substrate 6 of 5 is reduced), when the fluid flows in the first flow direction or the second flow direction, the same flow rate as that of the conventional motorized valve 1'can be obtained. It has been confirmed by the present inventor and others (detailed later).

Further, in addition to the above, the length L of the pipe expansion portion 11B in the horizontal pipe member 11 (the length in the center line direction of the horizontal pipe member 11) is the inner diameter of the valve chamber 7 (= inner diameter φC of the tubular base 6). When it is set to 1/2 or more, that is, the length L of the pipe expanding portion 11B is the same axis (center line) O of the tubular base 6 of the valve body 5 from the first opening 11a to which the horizontal pipe member 11 is connected. When the distance (in the lateral direction) to the axis (center line) O of the valve seat member 8 (valve port 9) or the lower pipe member 12 arranged above is set to be greater than or equal to the distance, the inside of the valve chamber 7 Since it is considered that the flow velocity can be reduced more reliably, it is possible to more effectively suppress the decrease in the flow rate.

[Results of verifying the change in flow rate with respect to the inner diameter of the expanded pipe member of the horizontal pipe member]
The present inventors, in order to confirm the effect of changing the shape of the valve body 5 (cylindrical base 6) and the horizontal pipe member 11 connected to the valve body 5, the general part 11A of the horizontal pipe member 11 Numerical analysis shows the change in flow rate when the inner diameter of the expansion portion is changed with respect to the diameter of the valve opening (= inner diameter of the general portion of the horizontal pipe member) while applying a predetermined pressure difference between the pipe member 12 and the lower pipe member 12. I verified it.

FIG. 3 is a graph showing a change in the flow rate of the motorized valve shown in FIG. 1 with respect to the inner diameter of the expanded portion of the horizontal pipe member. In the figure, the horizontal axis is the ratio of the inner diameter of the expanded pipe portion to the diameter of the valve opening (= the inner diameter of the general portion of the horizontal pipe member) (= φB / φA), and the vertical axis is the miniaturization of the valve body 5 (specifically). Shows the rate of increase in the flow rate when the flow rate of the electric valve (with the inner diameter φC of the tubular substrate 6 set to about 1.7 times the diameter φA of the valve port 9) as the reference (1.0). ● (black circle) indicates a change in the flow rate increase rate in the first flow direction (horizontal → horizontal), and Δ indicates a change in the flow rate increase rate in the second flow direction (bottom → horizontal). In addition, in FIG. 3, the flow rate of the conventional electric valve 1'shown in FIG. 4 in the first flow direction (horizontal → downward) (■: horizontal pipe member inner diameter / valve diameter = 1.0) increases the flow rate. The ratio = 1.07) and the flow rate in the second flow direction (bottom → lateral) (□: horizontal pipe member inner diameter / valve diameter = 1.0 and flow rate increase ratio = 1.01) are also shown.

From the graph of FIG. 3, it can be seen that the flow rate of the motorized valve increases as the inner diameter of the expanded portion of the horizontal pipe member becomes larger than the diameter of the valve opening (= the inner diameter of the general portion of the horizontal pipe member). In particular, it can be seen that the rate of increase in the flow rate is larger in the first flow direction (horizontal → lower) than in the second flow direction (lower → horizontal).

When the inner diameter of the expanded portion of the horizontal pipe member is 1.1 times or more the diameter of the valve opening (= the inner diameter of the general portion of the horizontal pipe member), it is in both the first flow direction and the second flow direction. It can be seen that a flow rate of 1'or higher than that of the conventional motorized valve shown in FIG. 4 can be obtained.

The flow rate coefficient (Cv) when the ratio of the inner diameter of the expanded pipe portion (= φB / φA) to the diameter of the valve opening (= the inner diameter of the general portion of the horizontal pipe member) is 1.1 to 1.5 is 5. It was 2 to 5.7.

From the above verification results, the flow rate of the electric valve tends to increase as the inner diameter of the expanded portion of the horizontal pipe member becomes larger than the diameter of the valve opening (= the inner diameter of the general portion of the horizontal pipe member). If the inner diameter of the pipe expansion portion is 1.1 times or more the diameter of the valve opening (= the inner diameter of the general portion of the horizontal pipe member), a flow rate of 1'or higher than that of the conventional electric valve shown in FIG. 4 can be obtained. Was confirmed.

In the above description, the solenoid valve of the present embodiment is used as an expansion valve in, for example, a heat pump type heating / cooling system, and is a bidirectional flow type solenoid valve in which a fluid flows in both directions. However, the solenoid valve of the present invention is used. Needless to say, can be applied to other systems other than the heat pump type heating / cooling system, and it is natural that it may be applied to an electric valve in which a fluid flows in only one direction.

1 Electric valve 5 Valve body 6 Cylindrical base 7 Valve chamber 8 Valve seat member 8a Valve seat 8A Small diameter upper 8B Large diameter lower 8c Bottom 9 Valve port 11 Horizontal pipe member 11a First opening 11A General part of horizontal pipe member 11B Horizontal pipe Pipe expansion part 12 Lower pipe member 12a Second opening 13 Cylindrical base 14 Cylindrical holding member 15 Bearing member 15i Female screw 17 Rotating elevating shaft 17a Male screw 19 Support member 20 Valve body 23 Thrust transmission member 40 Mysterious planetary gear type reduction mechanism 50 Stepping motor (elevating drive unit)
55 Stator 57 Rotor 58 Can

Claims (2)

A valve body having a valve chamber defined inside, a valve seat having a valve seat with a valve opening that opens into the valve chamber and provided at the bottom of the valve body, and a side portion of the valve chamber. A horizontal pipe member provided so as to communicate with the lower pipe member provided so as to communicate with the valve chamber via the valve opening, a valve body arranged so as to be able to move up and down in the valve chamber, and the valve. A lifting drive unit for raising and lowering the body with respect to the valve seat is provided.
An electric valve characterized in that the inner diameter of the horizontal pipe member opened in the valve chamber is larger than the inner diameter of the lower pipe member. The electric valve according to claim 1, wherein the inner diameter of the horizontal pipe member opened in the valve chamber is 1.1 times or more the diameter of the valve port.

Images