JP7383774B2 - Electric valve and refrigeration cycle system - Google Patents

Description

The present invention relates to an electric valve used in a refrigeration cycle system and the like, and a refrigeration cycle system.

BACKGROUND ART Conventionally, as an electric valve provided in a refrigeration cycle of an air conditioner, there is an electric valve that controls the flow rate in a small flow rate control area and a large flow rate control area. Such a motor-operated valve has applications (for example, as a dehumidification valve) that are mounted on an indoor unit, and is disclosed in, for example, Japanese Patent Application Publication No. 2019-132347 (Patent Document 1).

JP 2019-132347 Publication

In recent years, air conditioners for commercial and home use are required to be extremely quiet. The small flow rate control area is used, for example, to perform dehumidifying operation, and particularly in this small flow rate control area, it is required to reduce the sound of refrigerant passing through the constriction section between the auxiliary valve port and the needle valve.

An object of the present invention is to reduce the sound of refrigerant passing through a first throttle part in an electric valve configured such that the needle part does not sit on the valve seat around the valve port.

The motor-operated valve of the present invention allows the fluid in the valve chamber to flow downstream through the valve port, and also causes the needle portion, which rotates due to the rotation of the rotor of the drive portion, to advance and retreat in the axial direction of the valve port, so that the fluid flows through the valve port. In the motor-operated valve for controlling the flow rate of fluid, the motor-operated valve is configured such that the needle portion does not sit on a valve seat around the valve port, and the motor-operated valve is configured such that the needle portion does not sit on a valve seat around the valve port. and a second constriction section provided between the valve chamber and the downstream side, and the first constriction section is configured to close the needle section at a position where the needle section is closest to the valve port. The valve port is characterized by having a radial gap corresponding to the difference between the outer diameter of the straight part without a groove and the inner diameter of the valve port without a groove .

At this time, a main valve body that opens and closes the main valve port of the main valve seat, a sub-valve seat as the valve seat provided on the main valve body, a sub-valve port as the valve port, and the sub-valve port a sub-valve body as the needle portion that changes the opening degree of the sub-valve port, and the sub-valve body changes the opening degree of the sub-valve port when the main valve body closes the main valve port. It is characterized by having a two-stage flow rate control area, a small flow rate control area, and a large flow rate control area in which a large flow rate of fluid flows from the main valve port when the main valve element fully opens the main valve port. Electrically operated valves are preferred.

Further, it is preferable that the electric valve is characterized in that the second throttle portion is formed on the sub-valve seat or the sub-valve body.

Further, it is preferable that the motor-operated valve is characterized in that the second throttle portion is formed on the main valve seat or the main valve body.

Preferably, the motor-operated valve is characterized in that a plurality of the second throttle portions are formed on an opening edge of the sub-valve port of the sub-valve seat on the sub-valve chamber side.

Preferably, the motor-operated valve is characterized in that a plurality of the second throttle portions are formed on an opening edge of the main valve port on the main valve chamber side of the main valve seat.

Preferably, the motor-operated valve is characterized in that a plurality of the second throttle portions are formed around the axis at a portion of the sub-valve body that faces the sub-valve port.

Preferably, the motor-operated valve is characterized in that a plurality of the second throttle portions are formed around the axis at a portion of the main valve body that faces the main valve port.

Further, the second throttle portion is formed on at least one of the sub-valve seat or the sub-valve side of the sub-valve body and the main valve side of the main valve seat or the main valve body. Electrically operated valves are preferred.

Further, it is preferable to provide an electric valve characterized in that the second constriction portion is constituted by a groove or a hole.

The refrigeration cycle system of the present invention includes a compressor, an indoor heat exchanger, an outdoor heat exchanger, an electronic expansion valve provided between the indoor heat exchanger and the outdoor heat exchanger, and the indoor heat exchanger. A refrigeration cycle system including a dehumidification valve provided in an exchanger, characterized in that the electric valve is used as the dehumidification valve.

According to the motor-operated valve and refrigeration cycle system of the present invention, in the motor-operated valve configured so that the needle portion does not sit on the valve seat around the valve port, for example, the motor-operated valve having a two-stage flow control region can be used for particularly small flow control. It is possible to reduce the sound of refrigerant passing through the first constriction section in the region.

FIG. 2 is a longitudinal cross-sectional view of the electric valve according to the first embodiment of the present invention in a small flow rate control region state. FIG. 2 is a longitudinal cross-sectional view of the motor-operated valve according to the first embodiment when the main valve body is fully open and the operation is stopped or when the air conditioner is operating. FIG. 2 is an enlarged vertical cross-sectional view and an enlarged plan cross-sectional view of a sub-valve seat and a sub-valve port of the electric valve of the first embodiment. FIG. 3 is an enlarged view of the needle portion and the sub-valve port of the electric valve of the first embodiment in a small flow rate control region state. It is a figure which shows the modification 1 of 1st Embodiment. It is a figure which shows the modification 2 of 1st Embodiment. It is a figure showing a 2nd embodiment of the present invention. 1 is a diagram showing a refrigeration cycle system according to an embodiment of the present invention.

Next, embodiments of the electric valve and refrigeration cycle system of the present invention will be described with reference to the drawings. FIG. 1 is a longitudinal cross-sectional view of the motor-operated valve according to the first embodiment in a small flow rate control region state, and FIG. 2 is a longitudinal cross-section of the motor-operated valve according to the first embodiment when the main valve body is fully open and the operation is stopped or during cooling operation. 3 is an enlarged vertical sectional view (FIG. 3 (A)) and an enlarged plan sectional view (FIG. 3 (B)) of the auxiliary valve seat and auxiliary valve port of the electric valve of the first embodiment, and FIG. FIG. 3 is an enlarged view of the needle portion and the sub-valve port of the motor-operated valve according to the embodiment in a small flow rate control region state. Note that the concept of "up and down" in the following description corresponds to the up and down in the drawings of FIGS. 1 and 2. Further, in FIGS. 1 and 2, the detailed structure of the sub-valve seat and the sub-valve port is omitted. This electric valve 100 includes a valve housing 1, a guide member 2, a main valve body 3, a needle valve 4, and a drive section 5.

The valve housing 1 is made of, for example, brass or stainless steel and has a substantially cylindrical shape, and has a main valve chamber 1R inside thereof. A first joint pipe 11 that communicates with the main valve chamber 1R is connected to one side of the outer periphery of the valve housing 1, and a second joint pipe 12 is connected to a cylindrical portion extending downward from the lower end. Further, a cylindrical main valve seat 13 is formed on the main valve chamber 1R side of the second joint pipe 12 of the valve housing 1, and the inside of this main valve seat 13 is a main valve port 13a, and the second joint pipe 12 is connected to the main valve chamber 1R. The pipe 12 is connected to the main valve chamber 1R via the main valve port 13a. The main valve port 13a is a cylindrical through hole centered on the axis L (a penetrating hole). Note that the first joint pipe 11 and the second joint pipe 12 are fixed to the valve housing 1 by brazing or the like.

A guide member 2 is attached to an opening at the upper end of the valve housing 1 . The guide member 2 includes a press-fitting part 21 that is press-fitted into the inner peripheral surface of the valve housing 1, approximately cylindrical guide parts 22 and 23 that have a smaller diameter than the press-fitting part 21 and are located above and below the press-fitting part 21, and an upper guide. It has a holder part 24 extending above the part 22 and a ring-shaped flange part 25 provided on the outer periphery of the press-fitting part 21 . The press-fitting part 21, the guide parts 22, 23, and the holder part 24 are constructed as an integral part made of resin. Further, the flange portion 25 is, for example, a metal plate made of brass, stainless steel, or the like, and is integrally provided with the resin press-fit portion 21 by insert molding.

The guide member 2 is assembled to the valve housing 1 through a press-fitting portion 21 and is fixed to the upper end portion of the valve housing 1 via a flange portion 25 by welding. Further, in the guide member 2, a cylindrical guide hole 2A coaxial with the axis L is formed inside the press-fitting part 21 and the upper and lower guide parts 22, 23, and a guide hole 2A is formed in the center of the holder part 24. A female threaded portion 24a coaxial with the threaded portion 24a and its threaded hole are formed. The main valve body 3 is disposed inside the guide hole 2A inside the lower guide portion 23.

The main valve body 3 includes a main valve part 31 that seats and leaves the main valve seat 13, a holding part 32 having a cylindrical needle guide hole 32a, and a sub-valve seat that forms the bottom of the needle guide hole 32a. 33, and a retainer 34 provided at the end of the holding portion 32. Note that a portion of the lower side of the needle guide hole 32a serves as a sub-valve chamber 3R. A washer 43 attached to a rotor shaft 51, which will be described later, and a guiding boss portion 44 formed integrally with the rotor shaft 51 are inserted into the needle guide hole 32a of the holding portion 32, and a ring-shaped retainer 34 is inserted into the needle guide hole 32a of the holding portion 32. is fixed to the upper end of the holding portion 32 by fitting or welding.

A main valve spring 3a is disposed between the retainer 34 and the upper end of the guide hole 2A, and the main valve spring 3a causes the main valve element 3 to move toward the main valve seat 13 (in the closing direction). energized. A cylindrical sub-valve port 33a centered on the axis L is formed at the center of the sub-valve seat 33. Further, a communication hole 32b is formed in at least one part of the side surface of the holding part 32, and the needle valve 4 as a sub-valve body connects the sub-valve port 33a. When in the open state, the main valve chamber 1R, the sub-valve chamber 3R, the sub-valve port 33a, and the main valve port 13a are electrically connected.

The needle valve 4 is a truncated cone-shaped "auxiliary valve body" that is formed integrally with the lower end of a rotor shaft 51, which will be described later, and whose diameter gradually decreases toward the tip connected to the rotor shaft 51 side. The needle portion 42 is integrally formed. Further, the needle valve 4 includes an annular washer 43 made of a lubricating resin and attached to the rotor shaft 51, and a guide boss portion 44 formed integrally with the rotor shaft 51. The washer 43 and guide boss portion 44 are slidably inserted into the needle guide hole 32a.

A case 14 is airtightly fixed to the upper end of the valve housing 1 by welding or the like, and a drive section 5 is configured inside and outside the case 14. The drive unit 5 includes a stepping motor 5A, a screw feeding mechanism 5B that advances and retreats the needle valve 4 by rotation of the stepping motor 5A, and a stopper mechanism 5C that restricts the rotation of the stepping motor 5A.

The stepping motor 5A includes a rotor shaft 51, a magnet rotor 52 rotatably disposed inside the case 14, a stator coil 53 disposed opposite to the magnet rotor 52 on the outer periphery of the case 14, and other components. It is composed of a yoke, an exterior member, etc. (not shown). The rotor shaft 51 is attached to the center of the magnet rotor 52 via a bush, and a male threaded portion 51a is formed on the outer periphery of the rotor shaft 51 on the guide member 2 side. The male threaded portion 51a is screwed into the female threaded portion 24a of the guide member 2, so that the guide member 2 supports the rotor shaft 51 on the axis L. The female threaded portion 24a of the guide member 2 and the male threaded portion 51a of the rotor shaft 51 constitute a screw feeding mechanism 5B.

With the above configuration, when the stepping motor 5A is driven, the magnet rotor 52 and the rotor shaft 51 rotate, and the screw feeding mechanism 5B of the male threaded portion 51a of the rotor shaft 51 and the female threaded portion 24a of the guide member 2 causes the magnet rotor 52 to rotate. At the same time, the rotor shaft 51 moves in the direction of the axis L. Then, the needle valve 4 moves forward and backward in the direction of the axis L, and the needle valve 4 approaches or separates from the sub-valve port 33a. Further, when the needle valve 4 rises, the washer 43 engages with the retainer 34 of the main valve body 3, and the main valve body 3 moves together with the needle valve 4 and leaves the main valve seat 13. Note that the magnet rotor 52 is formed with a protrusion 52a, and as the magnet rotor 52 rotates, the protrusion 52a operates the rotation stopper mechanism 5C, and the lowermost position of the rotor shaft 51 (and the magnet rotor 52) and The top position is restricted.

In the small flow rate control region state shown in FIG. control is performed. For example, when the compressor of the refrigeration cycle system is stopped and the fluid (refrigerant) is stopped and the needle valve 4 and main valve body 3 are raised, the main valve port 13a is fully opened as shown in FIG. Become. This allows a large flow of fluid (refrigerant) to flow from the first joint pipe 11 to the second joint pipe 12 during cooling operation, and a large flow of fluid (refrigerant) from the second joint pipe 12 to the first joint pipe 11 during heating operation. Fluid (refrigerant) is flowed.

As shown in FIG. 3, a plurality (six in this example) of grooves 6 as "second constricted parts" are formed at the opening edge of the sub-valve port 33a on the side of the sub-valve chamber 3R. The grooves 6 are formed at equal intervals (every 60 degrees) around the axis L and at rotationally symmetrical positions with respect to the axis L. The length of the groove 6 in the axis L direction is shorter than the length of the sub-valve port 33a in the axis L direction, and the length of the groove 6 in the axis L direction from the sub-valve chamber 3R on the upstream side of the flow direction The groove 6 is formed so that the horizontal cross-sectional area thereof gradually decreases toward the second joint pipe side. Further, as shown in FIG. 4, the needle portion 42 includes a straight portion 42a made of a cylinder whose center line is the axis L, and a tapered portion 42b whose diameter is reduced toward the distal end. Further, the outer diameter of the straight portion 42a is smaller than the inner diameter of the auxiliary valve port 33a, and a first constricted portion (gap) is formed between the straight portion 42a and the auxiliary valve port 33a. Then, a constant flow rate of refrigerant flows through this first constriction section, thereby performing small flow rate control. Furthermore, during this small flow rate control, the pressure of the refrigerant flowing into the straight portion 42a and the constricted portion of the sub-valve port 33a is controlled by the groove 6 (second constricted portion) formed on the sub-valve chamber 3R side of the sub-valve port 33a. The differential pressure across the first constriction section, which is distributed around the axis L and constituted by the sub-valve seat 33 and the needle section 42, is reduced, and the sound of refrigerant passing through the first constriction section can be reduced.

As described above, in the electric valve 100 of the first embodiment, the auxiliary valve seat 33 and the needle valve 4 (the needle portion 42 of the auxiliary valve body), which operate in a small flow rate control region, are connected to the first constriction portion through which the refrigerant flows. A groove 6 (second constricted portion) is formed in the sub-valve seat 33. Therefore, the sound of refrigerant passing through the first constriction section between the sub-valve port 33a and the needle section 42 can be reduced.

5 to 7 are diagrams showing modifications of the electric valve of the first embodiment and the second embodiment. In each modification and the second embodiment, the entire configuration of the electric valve is shown except for the parts shown in FIGS. 5 to 7. This is similar to FIGS. 1 and 2.

Modification 1 in FIG. 5 is one in which a groove 7 is formed in the needle portion 42 as a “second constriction portion”. The groove 7 is formed from the base portion 42c of the needle portion 42 on the guide boss portion 44 side to the middle of the straight portion 42a. Further, a plurality of grooves 7 (six in this example) are formed, and the grooves 7 are formed at positions rotationally symmetrical to the axis L at equal intervals (every 60 degrees) around the axis L. Further, the horizontal cross-sectional area of the groove 7 becomes smaller as it approaches the sub-valve port 33a in the direction of the axis L. In this modification example 1, the groove 7 is formed only halfway up the straight part 42a, so the opening area of the throttle part between the straight part 42a and the auxiliary valve port 33a is constant as in the embodiment, and the flow rate is small. The flow rate during control can be kept constant.

Also in this modification example 1, during the small flow rate control, the pressure of the refrigerant flowing into the straight part 42a and the constricted part of the sub-valve port 33a is dispersed around the axis L by the groove 7 formed in the needle part 42, and The differential pressure across the throttle section formed by the valve seat 33 and the needle section 42 is reduced, and the sound of refrigerant passing through the throttle section can be reduced.

Modification 2 in FIG. 6 is one in which a groove 7' is formed in the needle portion 42 as a “second constriction portion”. The groove 7' is formed from the middle of the straight part 42a of the needle part 42 to the tapered part 42b. Further, a plurality of grooves 7' (six in this example) are formed, and the grooves 7' are formed at positions rotationally symmetrical to the axis L at equal intervals (every 60 degrees) around the axis L. There is. Also in this modification 2, during small flow rate control, the pressure of the refrigerant flowing into the straight part 42a and the constricted part of the sub-valve port 33a is dispersed around the axis L by the groove 7' formed in the needle part 42, and The pressure difference before and after the constriction section constituted by the seat 33 and the needle section 42 is reduced, and the sound of refrigerant passing through this constriction section can be reduced.

The second embodiment shown in FIG. 7 has features added to the main valve seat 13 and main valve port 13a in the first embodiment shown in FIGS. 1 and 2. Modification 1 of the second embodiment shown in FIG. 7A is such that a plurality of (six in this example) grooves 8 as "second throttle parts" are formed on the opening edge of the main valve port 13a in the main valve seat 13. This is what I did. Similarly to the first embodiment, the grooves 8 are also formed at equal intervals (every 60°) around the axis L at rotationally symmetrical positions with respect to the axis L. The groove 8 allows the refrigerant to flow from the main valve chamber 1R to the main valve port 13a even when small flow rate control is performed by the constriction between the auxiliary valve port 33a and the straight part 42a of the needle part 42. do. Therefore, the pressure difference across the constriction between the auxiliary valve port 33a and the needle portion 42 is reduced, and the sound of refrigerant passing through the constriction can be reduced. Modification 2 of the second embodiment shown in FIG. 7(B) is one in which a plurality (six in this example) of grooves 8' as "second throttle parts" are formed in the main valve part 31 of the main valve 3. . Similarly to the first embodiment, the grooves 8' are also formed at equal intervals (every 60 degrees) around the axis L and at rotationally symmetrical positions with respect to the axis L. The groove 8' allows the refrigerant to flow from the main valve chamber 1R to the main valve port 13a even when small flow rate control is performed by the constriction between the sub-valve port 33a and the straight part 42a of the needle part 42. act. Therefore, the pressure difference across the constriction between the auxiliary valve port 33a and the needle portion 42 is reduced, and the sound of refrigerant passing through the constriction can be reduced.

Next, the refrigeration cycle system of the present invention will be explained based on FIG. Refrigeration cycle systems are used, for example, in air conditioners such as household air conditioners. The motor-operated valve 100 of the embodiment is provided between the first indoor heat exchanger 91 (operates as a cooler during dehumidification) and the second indoor heat exchanger 92 (operates as a heater during dehumidification) of the air conditioner. The compressor 95, four-way valve 96, outdoor heat exchanger 94, and electronic expansion valve 93 constitute a heat pump refrigeration cycle. The first indoor heat exchanger 91, the second indoor heat exchanger 92, and the electric valve 100 are installed indoors, and the compressor 95, four-way valve 96, outdoor heat exchanger 94, and electronic expansion valve 93 are installed outdoors. They have heating and cooling equipment.

In the electric valve 100 of the embodiment as a dehumidification valve, the main valve body is fully opened during cooling or heating other than during dehumidification, and the first indoor heat exchanger 91 and the second indoor heat exchanger 92 are connected to one indoor heat exchanger. It is considered a heat exchanger. The integrated indoor heat exchanger and outdoor heat exchanger 94 function alternatively as an "evaporator" and a "condenser." That is, the electric valve 93 as an electronic expansion valve is provided between the evaporator and the condenser.

Note that the present invention is not limited to the embodiments described above, and includes other configurations that can achieve the object of the present invention, and the present invention also includes the following modifications. For example, in the above embodiment, the electric valve 100 used in an air conditioner such as a domestic air conditioner is illustrated, but the electric valve of the present invention is not limited to a household air conditioner, but may be used in a commercial air conditioner. It is applicable not only to air conditioners but also to various types of refrigerators.

Moreover, although the grooves 6, 7, 7', 8, and 8' serving as the "second constricted portions" in the embodiment have triangular cross sections, they may have square cross sections or circular cross sections. Furthermore, in each of the above embodiments, the grooves as the "second constricted part" are described as being equally spaced, but the grooves are not limited to being equally spaced. In order to cope with the influence of downward fluid flow, etc., a plurality of grooves may be formed at irregular intervals. Further, in each of the embodiments described above, the number of grooves is shown as six, but the number is not limited to six, and may be one or more than six (two or more).

In addition, in the first embodiment, a groove is formed in the sub-valve seat for the sub-valve body, and in the second embodiment, a groove is formed in the main valve seat, and the grooves are formed separately for the main valve seat and the sub-valve seat. Although an example has been given in which the valve seat is formed, the first embodiment and the second embodiment may be combined to form an embodiment in which a groove is formed in the sub-valve seat and a groove is further formed in the main valve seat. Further, as a modification, an embodiment may be adopted in which a groove is formed in the sub-valve seat and a groove is further formed in the main valve body. Furthermore, an embodiment may be adopted in which a groove is formed in the sub-valve body and a groove is formed in the main valve body. Furthermore, an embodiment may be adopted in which a groove is formed in the sub-valve body and a groove is formed in the main valve seat. Further, in the second embodiment, a groove is formed in the main valve body or the main valve seat, but the structure is not limited to a groove, and a “second constriction portion” formed of a hole or the like may be used.

The embodiments of the present invention have been described above in detail with reference to the drawings, and other embodiments have also been described in detail, but the specific configuration is not limited to these embodiments. Even if there are changes in the design within the scope of the invention, they are included in the present invention.

1 Valve housing 1R Main valve chamber 11 First joint pipe 12 Second joint pipe 13 Main valve seat 13a Main valve port 14 Case L Axis 2 Guide member 3 Main valve body 3a Main valve spring 3R Sub-valve chamber 31 Main valve part 32 Holding Part 32a Needle guide hole 32b Conduction hole 33 Sub-valve seat 33a Sub-valve port 4 Needle valve 42 Needle part (sub-valve body)
42a Straight part 43 Washer 44 Guide boss part 5 Drive part 6 Groove (notch part)
7 Groove (notch)
7' Groove (notch)
91 First indoor heat exchanger 92 Second indoor heat exchanger 93 Electronic expansion valve 94 Outdoor heat exchanger 95 Compressor 96 Four-way valve 100 Electrically operated valve

Claims (11)

An electric motor that controls the flow rate of fluid flowing through the valve port by causing the fluid in the valve chamber to flow downstream through the valve port, and by moving the needle part, which rotates due to the rotation of the rotor of the drive part, back and forth in the axial direction of the valve port. A motor-operated valve configured such that the needle portion does not sit on a valve seat around the valve port,
comprising a first constriction section consisting of a gap between the needle section and the valve port, and a second constriction section provided between the valve chamber and the downstream side,
At a position where the needle portion is closest to the valve port, the first constriction portion corresponds to the difference between the outer diameter of a straight portion of the needle portion that is cylindrical and does not have a groove, and the inner diameter of the valve port that does not have a groove. An electric valve characterized by having a radial clearance. A main valve body that opens and closes the main valve port of the main valve seat, a sub-valve seat as the valve seat provided on the main valve body, a sub-valve port as the valve port, and the opening degree of the sub-valve port. a sub-valve body as the needle portion that changes the opening degree of the sub-valve port, the sub-valve body changing the opening degree of the sub-valve port while the main valve body closes the main valve port. and a large flow rate control area in which a large flow rate of fluid flows from the main valve port when the main valve body fully opens the main valve port. 1. The electric valve according to 1. The electric valve according to claim 2, wherein the second throttle portion is formed on the sub-valve seat or the sub-valve body. The electric valve according to claim 2, wherein the second throttle portion is formed on the main valve seat or the main valve body. 4. The motor-operated valve according to claim 3, wherein a plurality of the second throttle portions are formed on an opening edge of the sub-valve port of the sub-valve seat on the sub-valve chamber side. 5. The electric valve according to claim 4, wherein a plurality of the second throttle portions are formed on an opening edge of the main valve port of the main valve seat on the main valve chamber side. The motor-operated valve according to claim 3, wherein a plurality of the second throttle portions are formed around the axis at a portion of the sub-valve body facing the sub-valve port. 5. The electric valve according to claim 4, wherein a plurality of the second throttle portions are formed around the axis at a portion of the main valve body that faces the main valve port. Claim characterized in that the second throttle portion is formed on at least one of the sub-valve seat or the sub-valve side of the sub-valve body, and the main valve seat or the main valve side of the main valve body. 2. The electric valve according to 2. The motor-operated valve according to any one of claims 3 to 9, wherein the second constriction portion is constituted by a groove or a hole. A compressor, an indoor heat exchanger, an outdoor heat exchanger, an electronic expansion valve provided between the indoor heat exchanger and the outdoor heat exchanger, and a dehumidification valve provided in the indoor heat exchanger. A refrigeration cycle system comprising: the electric valve according to any one of claims 1 to 10 being used as the dehumidification valve.

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