JP7187427B2 - Rotary switching valve and refrigeration cycle system - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotary switching valve and a refrigerating cycle system that are used in a heat pump refrigerating cycle or the like and that switch a refrigerant flow path.

Conventionally, there is one disclosed in Japanese Patent No. 4602593 (Patent Document 1), for example, as this type of rotary switching valve (four-way switching valve). In Patent Document 1, when switching from cooling to heating or from heating to cooling, the main valve on the valve seat is rotated. is open to reduce the pressure difference applied to the main valve. That is, after the sub-valve rotates to open the pressure equalizing hole and rotate the main valve in a state where it is lifted from the valve seat due to the pressure difference, the sub-valve rotates in the opposite direction to close the pressure equalizing hole and the main valve is to be seated.

Japanese Patent No. 4602593

In Patent Document 1, when the sub-valve closes the equalizing hole, the main valve is floating from the valve seat. When the sub valve rotates in the opposite direction, the main valve rotates together with the drive unit and rotates integrally with the drive unit.

SUMMARY OF THE INVENTION An object of the present invention is to enable stable switching operation of a main valve in a rotary switching and refrigeration cycle system having a sub-valve for opening and closing a pressure equalizing passage of the main valve.

A rotary switching valve according to the present invention comprises a case member having a valve chamber, a valve seat provided opposite to the valve chamber, and a valve seat rotatably disposed on the valve seat in the valve chamber about an axis. and a sub-valve for opening and closing a pressure equalizing hole of the main valve. In the rotary switching valve for switching the flow path communicating with the port of the valve seat, the case member is provided with a stopper portion for restricting the position of the main valve in the axial direction when the main valve floats in the axial direction. and an upper end surface of the main valve abuts against the stopper portion .

In this case, preferably, the rotary switching valve is characterized in that the free movement distance of the main valve in the axial direction is smaller than the free movement distance of the members other than the main valve, including the auxiliary valve, in the axial direction.

Preferably, the rotary switching valve is characterized in that the passage area calculated from the inner diameter of the suction port formed in the valve seat and the free movement distance of the main valve is smaller than the opening area of the discharge port.

Further, the rotary switching valve characterized in that the flow passage area calculated from the outer peripheral length of the sliding rib surrounding the low-pressure flow passage of the main valve and the free movement distance of the main valve is smaller than the opening area of the discharge port. is preferred.

Preferably, the rotary switching valve is characterized in that at least one of the main valve and the case member is provided with a communication groove that communicates between the outer circumference of the main valve and the back space of the main valve.

A refrigerating cycle system of the present invention is a refrigerating cycle system including a compressor, a condenser, an expansion valve, an evaporator, and a channel switching valve , wherein the rotary switching valve is the channel switching valve It is characterized by being used as

According to the rotary switching valve and refrigerating cycle system of the present invention, when the auxiliary valve is rotated to open the pressure equalizing hole of the main valve and the main valve is lifted from the valve seat in the axial direction, the main valve moves to the stopper portion. , and a frictional force is generated between the main valve and the stopper portion. Therefore, the main valve does not rotate when the sub-valve is counter-rotated to close the pressure equalizing hole, so that the main valve can be stably switched.

FIG. 3 is a vertical cross-sectional view of the main part of the main valve of the rotary switching valve according to the first embodiment of the present invention in a seated state; FIG. 4 is a vertical cross-sectional view of the main part of the main valve of the rotary switching valve in the first embodiment in a floating state; 4 is a top view of the main valve of the rotary switching valve in the first embodiment; FIG. It is a bottom view of the main valve of the rotary switching valve in the first embodiment. It is a bottom view of the sub-valve of the rotary switching valve in the first embodiment. FIG. 4 is a top view of the valve seat of the rotary switching valve in the first embodiment; FIG. 8 is a vertical cross-sectional view of the main part of the main valve of the rotary switching valve according to the second embodiment of the present invention in a floating state; FIG. 10 is a top view of a main valve of a rotary switching valve in a second embodiment; FIG. 5 is a diagram illustrating a preferred example of the floating distance of the main valve in the first and second embodiments; BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows the refrigerating-cycle system of embodiment of this invention.

Next, embodiments of a rotary switching valve and a refrigeration cycle system of the present invention will be described with reference to the drawings. FIG. 1 is a vertical cross-sectional view of the main part of the rotary switching valve in the seated state of the main valve according to the first embodiment of the present invention, and FIG. 2 is a vertical cross-sectional view of the main part of the rotary switching valve in the floating state. 3 is a top view of the main valve of the rotary switching valve, FIG. 4 is a bottom view of the main valve of the rotary switching valve, FIG. 5 is a bottom view of the auxiliary valve of the rotary switching valve, and FIG. FIG. 4 is a top view of the valve seat of the switching valve; It should be noted that the concept of "up and down" in the following description corresponds to up and down in the drawings of FIGS. 1 and 2. FIG.

A rotary switching valve 100 of the first embodiment has a main valve 1 , an auxiliary valve 2 , a valve seat member 3 , a case member 4 , a driving portion 5 and a center shaft 6 . The valve seat member 3 is composed of a thin cylindrical valve seat 31 and a flange portion 32 formed on the outer periphery of the valve seat 31 . A substantially cylindrical valve chamber 4A is formed in the case member 4. As shown in FIG. The main valve 1, the sub-valve 2, the driving portion 5, and the central shaft 6 are housed in the valve chamber 4A. It is fixed between the seat member 3 and the case member 4 . The valve seat member 3 is attached to the case member 4 so that the valve seat 31 is fitted to the opening of the valve chamber 4A of the case member 4 and the flange portion 32 is brought into contact with the lower end of the case member 4. there is

The main valve 1 is a member made of resin and having a circular outer periphery. A piston ring 12 a is arranged around the piston portion 12 . The main valve 1 is rotatably arranged around the axis X of the central shaft 6 by passing the central shaft 6 through the central bearing portion 13 . The space in which the piston portion 12 is accommodated in the upper portion of the valve chamber 4A is a cylindrical guide hole 41. It is movable in the axis X direction. The lower surface of the upper end of the guide hole 41 serves as a stopper portion 411 with which the upper end surface 121 of the piston portion 12 abuts when the main valve 1 rises from the valve seat 31 of the valve seat member 3 as will be described later. .

In the skirt portion 11 of the main valve 1, a dome-shaped low-pressure passage 11A is formed on one side of the axis X. A communicating pressure equalizing passage 11a is formed. In addition, sliding ribs 111 are formed on the bottom surface of the skirt portion 11 on the side of the valve seat member 3 so as to surround the outer periphery of the low-pressure flow path 11A, and the sliding ribs 111 are formed at two locations on the side opposite to the axis X. Sliding ribs 112, 112 are formed on the . Further, in the skirt portion 11, a high-pressure space 11B is formed on the opposite side of the axis X with respect to the low-pressure flow path 11A, and a D port 31D, which will be described later, is always open. Both ends of this opening in the direction around the axis X are stop pin contact portions 113 respectively. This stop pin contact portion 113 contacts a stop pin 31a provided on a valve seat 31, which will be described later.

Further, as shown in FIG. 3, a sub-valve seat plate 14 made of a metal plate (in this example, SUS) is arranged on the inner bottom portion of the piston portion 12 . A pressure equalizing hole 14a is formed in the sub valve seat plate 14 at a position corresponding to the pressure equalizing passage 11a. A part of the inner peripheral surface of the piston portion 12 is formed with a projecting portion 15 projecting toward the axis X side within a range of approximately 90°. A portion 15a. The sub-valve locking portion 15a abuts on a main valve locking portion 21a of the sub-valve 2, which will be described later.

As shown in FIG. 5, the sub-valve 2 has a substantially semi-disk-shaped flange portion 21 housed in the sub-valve housing chamber of the piston portion 12 of the main valve 1 and a central boss portion 22. A substantially rectangular square hole 22 a is formed in the center of the boss portion 22 . A slide valve portion 23 projecting in an annular shape is formed on the surface of the flange portion 21 on the side of the main valve 1 . The distance of the slide valve portion 23 from the axis X is equal to the distance from the axis X of the pressure equalizing hole 14a of the sub-valve seat plate 14 of the main valve 1 . Further, on the periphery of the flange portion 21 around the axis X, there are main valve locking portions 21a forming radial end faces. It is alternatively locked to the valve locking portion 15a.

As shown in FIG. 6, the valve seat 31 has a D port 31D communicating with the valve chamber 4A and the refrigerant discharge side of the compressor, and an S port communicating with the low pressure passage 11A and the refrigerant suction side of the compressor. 31S, a C switching port 31C communicating with the outdoor heat exchanger side, and an E switching port 31E communicating with the indoor heat exchanger side are formed. These ports are opened at positions separated by 90° from each other.

As shown in FIG. 1, the drive unit 5 has a worm wheel 51 rotatably arranged on the central shaft 6 and a worm gear 52 meshed with the worm wheel 51. The worm gear 52 is It is fixed to the drive shaft of a motor (not shown). The worm wheel 51 has a cam portion 51a projecting toward the sub valve 2, and the worm wheel 51 is rotatably arranged on the central shaft 6 by the cam portion 51a. Further, the cam portion 51a is fitted into the substantially rectangular square hole 22a of the sub valve 2. As shown in FIG. As a result, the sub valve 2 is slidable only in the direction of the axis X in a state where rotation about the axis X is restricted with respect to the worm wheel 51, and the sub valve 2 cooperates with the worm wheel 51 to rotate. do. A coil spring 53 is arranged between the worm wheel 51 and the sub valve 2 to bias the sub valve 2 toward the main valve 1 side.

With the above configuration, the driving force of the worm gear 52 and the worm wheel 51 of the drive unit 5 is applied to the sub valve 2 through the cam portion 51a of the worm wheel 51, and the sub valve 2 rotates around the axis X. . When the sub valve 2 rotates, the slide valve portion 23 slides on the sub valve seat plate 14 of the main valve 1, and the pressure equalizing hole 14a of this sub valve seat plate 14 opens. As a result, the pressure equalizing passage 11a in the main valve 1 is opened, and the pressure of the fluid above the main valve 1 escapes into the low pressure passage 11A (low pressure side). Here, the high-pressure fluid flows into the upper part of the piston 1 through the clearance between the piston ring 12a (and the piston portion 12) of the main valve 1 and the guide hole 41 and the clearance between the central shaft 6 and the bearing portion 13. The flow rate flowing into the upper portion of the piston 1 is set smaller than the flow rate escaping from the pressure equalizing hole 14a. Therefore, a pressure difference is generated between the upper and lower sides of the piston ring 12a, and the main valve 1 rises from the valve seat 31. As shown in FIG. Then, when the main valve 1 floats, the upper end surface 121 of the piston portion 12 of the main valve 1 contacts the stopper portion 411 of the case member 4 .

When the sub valve 2 is further rotated, the main valve locking portion 21a of the sub valve 2 contacts the sub valve locking portion 15a of the main valve 1, and the sub valve 2 and the main valve 1 rotate together. Then, the stop pin contact portion 113 of the main valve 1 comes into contact with the stop pin 31a provided on the upper surface of the valve seat 31, and the rotation stops at this predetermined position. Next, when the worm wheel 51 of the drive unit 5 is rotated in the opposite direction, the sub valve 2 rotates in the opposite direction, the slide valve portion 23 of the sub valve 2 slides on the sub valve seat plate 14, and the sub valve seat plate 14 pressure equalizing holes 14a are closed. As a result, the pressure equalizing passage 11a is closed, pressure is accumulated in the upper portion of the main valve 1, and the pressure difference between the upper portion of the main valve 1 and the inside of the low pressure passage 11A (low pressure side) causes the main valve 1 to move to the valve seat 31. take a seat.

As described above, when the sub valve 2 is reversely rotated while the main valve 1 is floating above the valve seat 31, the slide valve portion 23 of the sub valve 2 slides on the sub valve seat plate 14. 1, the upper end surface 121 of the piston portion 12 is in contact with the stopper portion 411 of the case member 4. Therefore, the frictional force between the upper end surface 121 and the stopper portion 411 causes the position of the main valve 1 around the axis X to be It remains fixed. Therefore, the counter-rotation of the sub-valve 2 allows the slide valve portion 23 to reliably close the equalizing hole 14a of the sub-valve seat plate 14, i.e., the equalizing passage 11a.

Further, as shown in FIG. 1, the floating distance L1 of the main valve 1 is smaller than the floating distance L2 of the sub valve 2. As shown in FIG. Therefore, the main valve 1 (upper end surface 121 ) can be reliably brought into contact with the stopper portion 411 .

FIG. 7 is a vertical cross-sectional view of a principal part of a seated state of a main valve of a rotary switching valve according to a second embodiment of the present invention, and FIG. 8 is a top view of the main valve of the same rotary switching valve. Members and elements similar to those of the first embodiment are denoted by the same reference numerals as those of the first embodiment, and detailed description thereof is omitted. The second embodiment differs from the first embodiment in that communication grooves 12A are provided at four locations on the upper end of the piston portion 12 of the main valve 1. As shown in FIG.

The opening area of this communication groove 12A is larger than the opening area of the clearance between the piston ring 12a and the guide hole 41. With the upper end surface 121 in contact with the stopper portion 411 of the case member 4, the high pressure of the clearance between the outer periphery of the piston portion 12 and the guide hole 41 is applied to the back space of the piston portion 12 (main upper space of the main valve 1). will also be supplied. Therefore, the pressure difference between the upper and lower sides of the piston ring 12a is reduced, and the pressing force of the main valve 1 (upper end surface 121) on the stopper portion 411 can be reduced. Therefore, the frictional force between the upper end surface 121 and the stopper portion 411 can be ensured, and the power required for the switching operation of the main valve 1 can be reduced, so that the stable switching operation can be obtained. Note that the communication groove as described above may be provided on the side of the stopper portion 411 of the case member 4 .

Preferred examples of the first and second embodiments are as follows. For example, as shown in FIG. 2, when the main valve 1 rises from the valve seat 31 and the upper end surface 121 of the piston portion 12 contacts the stopper portion 411, the sliding rib 111 of the main valve 1 and the valve seat 31 is the floating distance L1 of the main valve 1. Then, as shown in FIG. 9, the flow path area determined (calculated) from the inner diameter "D1" of the S port 31S, which is the "intake port" of the valve seat 31, and the free movement distance "L1" of the main valve 1 is " It is preferable that the floating distance "L1" is set so as to be smaller than the opening area of the D port 31D, which is the discharge port (inner diameter D2). i.e.
From π×D1×L1<π×(D2/2) ² L1<(D2/2) ² /D1
It is preferable that Thereby, an appropriate pressure difference is applied to the main valve 1 .

Further, the flow passage area determined (calculated) from the outer peripheral length "S" of the sliding rib 111 surrounding the low-pressure flow passage 11A of the main valve 1 and the free movement distance "L1" of the main valve 1 (hatched area in FIG. 9). However, it is preferable that the floating distance "L1" is set so as to be smaller than the opening area of the D port 31D, which is the "discharge port". i.e.
From S×L1<π×(D2/2) ² L1<π×(D2/2) ² /S
It is preferable that Thereby, an appropriate pressure difference is applied to the main valve 1 .

If the floating distance of the main valve 1 is large, a large amount of fluid on the high-pressure side flows out to the low-pressure side after the main valve 1 rises. However, with the above settings this does not happen. That is, by reducing the floating distance L1 of the main valve 1, the outflow to the low-pressure side can be suppressed, an appropriate pressure difference is applied to the main valve 1, and a stable switching operation can be performed.

FIG. 10 is a diagram showing a refrigeration cycle system of an embodiment, which is an example of a refrigeration cycle system for an air conditioner. The air conditioner has a compressor 50, an outdoor heat exchanger 60, an expansion valve 70, an indoor heat exchanger 80, and a rotary switching valve 100 of the embodiment. are connected to form a heat pump refrigeration cycle system.

The flow path of the refrigeration cycle system is switched between two flow paths for cooling operation and heating operation by the rotary switching valve 100 of the embodiment. ). The rotary switching valve 100 shown in FIG. 10 is viewed from the back side of the valve seat portion 3, and shows only the positional relationship of the main parts. The contact part is illustrated. Also, the S port 31S, D port 31D, E switching port 31E, and C switching port 31C are indicated by symbols "S," "D," "E," and "C," respectively.

During the cooling operation of FIG. 10(A), in the rotary switching valve 100, the S port "S" is connected to the E switching port "E" by the low pressure passage 11A of the main valve, and the D port "D" is connected by the high pressure space 11B. It is connected to the C switching port "C". Then, as indicated by an arrow in the figure, the refrigerant as a fluid compressed by the compressor 50 flows into the D port "D" of the rotary switching valve 100 and flows from the C switching port "C" to the outdoor heat exchanger 60. Refrigerant flowing in and out of the outdoor heat exchanger 60 flows into the expansion valve 70 . The refrigerant is expanded by the expansion valve 70 and supplied to the indoor heat exchanger 80 . Refrigerant flowing out of the indoor heat exchanger 80 flows from the E switching port “E” to the S port “S” at the rotary switching valve 100 and is circulated to the compressor 50 from the S port “S”.

During the heating operation of FIG. 10B, in the rotary switching valve 100, the low-pressure passage 11A of the main valve connects the S port "S" to the C switching port "C", and the high-pressure space 11B connects the D port "D". It is connected to the E switching port "E". Then, as indicated by arrows in the figure, the refrigerant compressed by the compressor 50 flows into the D port "D" of the rotary switching valve 100 and flows into the indoor heat exchanger 80 from the E switching port "E", Refrigerant flowing out of the indoor heat exchanger 80 flows into the expansion valve 70 . The refrigerant is expanded by the expansion valve 70 and supplied to the outdoor heat exchanger 60 . Refrigerant flowing out of the outdoor heat exchanger 60 flows from the C switching port “C” to the S port “S” at the rotary switching valve 100 and is circulated from the S port “S” to the compressor 50 .

In the above-described first and second embodiments, the worm gear mechanism including the worm gear 52 and the worm wheel 51 has been described as the gear mechanism for transmitting the rotation of the drive shaft of the motor to the rotation of the sub valve. , and other gear mechanisms may be used. For example, a spur gear, a planetary gear mechanism, or the like may be used.

Although the embodiments of the present invention have been described in detail above with reference to the drawings, the specific configuration is not limited to these embodiments, and design modifications and the like are made within the scope of the present invention. is included in the present invention.

1 main valve 11 skirt portion 11A low-pressure passage 11B high-pressure space 11a pressure equalizing passage 111 sliding rib 112 sliding rib 113 stop pin contact portion 12 piston portion 12A communicating groove 12a piston ring 121 upper end surface 13 bearing portion 14 sub-valve seat Plate 14a Pressure equalizing hole 15 Protruding portion 15a Sub-valve locking portion 2 Sub-valve 21 Flange portion 21a Main valve locking portion 22 Boss portion 22a Square hole 23 Slide valve portion 3 Valve seat member 31 Valve seat 31D D port 31S S port 31E E switching port 31C C switching port 31a Stop pin 32 Flange portion 4 Case member 4A Valve chamber 41 Guide hole 411 Stopper portion 5 Driving portion 51 Worm wheel 51a Cam portion 52 Worm gear 53 Coil spring 6 Central axis X Axis 50 Compressor 60 Outdoor heat Exchanger 70 Expansion valve 80 Indoor heat exchanger 100 Rotary switching valve

Claims (6)

a case member having a valve chamber; a valve seat provided facing the valve chamber; a main valve disposed on the valve seat in the valve chamber so as to be rotatable about an axis; and a sub valve for opening and closing a pressure equalizing hole, and by opening the pressure equalizing hole and floating the main valve from the valve seat in the axial direction to rotate the main valve, the main valve communicates with the port of the valve seat. In the rotary switching valve that switches the flow path,
The case member includes a stopper portion that regulates the position of the main valve in the axial direction when the main valve floats in the axial direction ,
A rotary switching valve , wherein an upper end face of the main valve is in contact with the stopper portion . 2. The rotary switching valve according to claim 1, wherein the free movement distance in the axial direction of the main valve is smaller than the free movement distance in the axial direction of members other than the main valve, including the sub-valve. 3. The rotary switching valve according to claim 2, wherein a passage area calculated from an inner diameter of the suction port formed in the valve seat and a free movement distance of the main valve is smaller than an opening area of the discharge port. 3. A flow passage area calculated from an outer peripheral length of a sliding rib surrounding the low-pressure flow passage of the main valve and a free movement distance of the main valve, according to claim 2, wherein a flow passage area is smaller than an opening area of the discharge port. Rotary switching valve. 5. The rotary switching system according to claim 3, wherein at least one of said main valve and said case member is provided with a communication groove for communicating between an outer periphery of said main valve and a back space of said main valve. valve. A refrigeration cycle system comprising a compressor, a condenser, an expansion valve, an evaporator, and a flow path switching valve, wherein the rotary switching valve according to any one of claims 1 to 5 is the A refrigeration cycle system characterized by being used as a flow path switching valve.

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