JP2017210970A - Channel changeover valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a channel changeover valve capable of changing-over a flow direction (a channel) of fluid efficiently by a simple configuration.SOLUTION: There is provided an ascending or descending driving part for ascending or descending a valve shaft 20 in a direction of axis line O. An inner housing 9A is provided with at least two inner ports p1 to p3 opened into a valve chamber 7A while being spaced apart in the direction of axis line O and opened there and at the same time at least one of communicating ports p11, p12 always communicating the valve chamber 7A and a communicating space 8A is opened, an outside port p10 always communicated with the communicating space is opened at an outer housing 9B, an upper back pressure chamber 30 and a lower back pressure chamber 31 are always communicated to each other, the valve shaft is ascended or descended in the valve chamber under a state in which at least two valve bodies 21 to 23 arranged at the valve shaft are internally contacted with the inner housing, thereby the communicated state between at least two of inner ports and the outer port is changed over.SELECTED DRAWING: Figure 18

Description

  The present invention relates to a flow path switching valve, for example, a flow path switching valve such as an electric valve used in a heat pump air conditioning system.

  As this type of flow path switching valve, conventionally, a pilot solenoid valve using a solenoid coil is used to move the slide valve body within the valve body in the refrigerant flow path switching six-way valve or eight-way valve, and is provided in the valve seat. It is known to switch between a cooling operation (defrosting operation) and a heating operation by switching the communication state of the ports, that is, the refrigerant flow direction (flow path) (for example, see Patent Document 1 below).

JP-A-8-170864

  By the way, in the conventional flow path switching valve, by introducing a high pressure into the pressure conversion chamber formed on both sides of the piston provided in the valve body by controlling the energization state of the solenoid coil of the pilot solenoid valve, The derivation is controlled, whereby the slide valve element fixed to the piston is moved within the valve body. Therefore, it is necessary to separately prepare a pilot electromagnetic valve for driving the slide valve body at the time of switching the flow path, and there are problems that the configuration becomes complicated and miniaturization is difficult. In addition, when an electromagnetic valve is used as a pilot valve, the opening area of both ports changes abruptly at the time of switching, and high-pressure refrigerant flows into the low-pressure side port (conduit) all at once. There is also a problem that a large pressure fluctuation occurs and a loud noise (switching sound) is generated.

  The present invention has been made in view of the above circumstances. The object of the present invention is to enable efficient switching of the fluid flow direction (flow path) with a relatively simple configuration. An object of the present invention is to provide a flow path switching valve that can contribute to downsizing, large capacity, power saving, and the like.

  In order to solve the above-described problems, a flow path switching valve according to the present invention is arranged on the outside of a cylindrical inner housing having a valve chamber and an outer side of the inner housing so as to form a communication space outside the inner housing. An outer housing, a valve shaft disposed in the valve chamber so as to be movable up and down, and having at least two valve bodies inscribed in the inner housing spaced apart in the axial direction, and the valve A lift drive unit for raising and lowering the valve shaft in the axial direction indoors, and the lift drive unit is rotatably arranged around a rotation axis extending in a direction perpendicular to the axial direction; A stepping motor having a stator for rotating the rotor, a rotary shaft that is rotated integrally with the rotor, and a motion conversion mechanism that converts the rotary motion of the rotary shaft into the vertical motion of the valve shaft. You In addition, the inner housing has at least two inner ports that open to the valve chamber spaced apart in the axial direction, and at least one communication port that always communicates the valve chamber and the communication space. The outer housing is opened with an outer port that is always in communication with the communication space, and an upper back pressure chamber defined above the at least two valve bodies in the valve chamber and the valve chamber in the valve chamber. The lower back pressure chamber defined below the at least two valve bodies is always in communication with the at least two valve bodies in the state where the at least two valve bodies are inscribed in the inner housing. The communication state between the at least two inner ports and the outer port is switched by raising and lowering the valve shaft in the valve chamber. It is characterized in that that is so.

  In a preferred aspect, the motion conversion mechanism is composed of drive teeth formed on the outer periphery of the rotating shaft and driven teeth that are formed on the valve shaft and mesh with the drive teeth.

  In another preferred embodiment, the rotation shaft is rotated around the rotation axis while being prevented from moving in the direction of the rotation axis.

  In another preferred aspect, the stepping motor is attached to the side of a base member attached to the end opening of the outer housing.

  In a further preferred aspect, a lateral hole into which the rotating shaft is inserted and a vertical hole into which the valve shaft is inserted are provided inside the base member.

  In another preferred embodiment, the communication space is formed on the outer periphery of the inner housing or formed on a part of the outer periphery of the inner housing.

  In another preferred embodiment, a D-cut surface is provided on the outer periphery of the inner housing, and the communication space is formed by the D-cut surface and the inner peripheral surface of the outer housing.

  In another preferred embodiment, the at least two inner ports and the outer port are opened on opposite sides or the same side as viewed in the axial direction.

  In another preferred embodiment, the communication port is located above the at least two inner ports and below the at least two inner ports, the uppermost valve body and the lowermost valve of the at least two valve bodies. It is opened at the same distance as the body.

  In another preferred embodiment, the outer port communicates with both the uppermost inner port and the lowermost inner port of the at least two inner ports when the valve stem is in a predetermined position. .

  In another preferred aspect, the outer port is opened in the communication space so as to always communicate with the communication space, or is opened at the same height as the communication port in the inner housing. It always communicates with the communication space through the opening.

  In another preferred embodiment, the upper back pressure chamber and the lower back pressure chamber are always communicated with each other via a communication passage provided in the valve shaft.

  In another preferred embodiment, the upper back pressure chamber and the lower back pressure chamber are always communicated with each other via the communication space.

  In another preferred embodiment, a seal member is attached to the outer periphery of the at least two valve bodies, and a packing having a hardness higher than that of the seal member is attached to the outside of the seal member.

  In another preferred embodiment, a concave surface portion is provided in a portion where the at least two inner ports and the at least one communication port are formed on the inner periphery of the inner housing.

  In a further preferred aspect, a tapered surface portion is provided on the upper surface and / or the lower surface of the concave surface portion.

  In another preferred aspect, the valve shaft includes a plurality of connecting shaft components each provided with one valve body.

  In another preferred embodiment, a lid-like member having a stopper portion for restricting the lowering of the valve shaft is attached to the outer housing or the inner housing.

  In a further preferred aspect, the lid-like member is configured to always communicate the upper back pressure chamber and the lower back pressure chamber when the valve shaft is brought into contact with the stopper portion and stopped. A vertical hole and a horizontal hole communicating with a communication path provided in the valve shaft are provided.

  According to the flow path switching valve of the present invention, the valve shaft is moved up and down in the valve chamber by the lift drive unit in a state where at least two valve bodies provided on the valve shaft are inscribed in the inner housing. Since the communication state (flow direction) between the at least two inner ports provided and the outer port provided in the outer housing is switched, the flow direction (flow path) of the fluid can be efficiently controlled with a relatively simple configuration. The upper back pressure chamber defined above the at least two valve bodies and the lower back pressure chamber defined below the at least two valve bodies are always in communication with each other. As a result, the load acting on the valve body when switching the flow path can be made as small as possible to reduce the drive torque of the valve body, thereby further reducing the size, increasing the capacity, and reducing power consumption. Mode That.

  A stepping motor having a rotor disposed to rotate around a rotation axis extending in a direction perpendicular to the axial direction and a stator for rotating the rotor; For example, from a heating operation to a defrosting operation and a defrosting operation because it has a rotating shaft that is rotated integrally with the rotor, and a motion conversion mechanism that converts the rotary motion of the rotating shaft into a lifting motion of the valve shaft When switching from heating to heating, the pressure difference between the high pressure side and the low pressure side can be reduced, so noise can be effectively reduced and the stepping motor that constitutes the lift drive unit can be laid sideways on the valve body. (Transversely), the overall length of the flow path switching valve can be shortened, the overall configuration can be simplified, and the time required for switching the communication state (flow path) can be shortened.

The longitudinal cross-sectional view which shows the 1st flow state (valve shaft: descending position) of 1st Embodiment of the flow-path switching valve which concerns on this invention. The longitudinal cross-sectional view which shows the 2nd flow state (valve shaft: ascending position) of the flow-path switching valve shown by FIG. The perspective view which shows the cover-like member of the flow-path switching valve shown by FIG. The longitudinal cross-sectional view which shows the 1st flow state (valve shaft: descending position) of 2nd Embodiment of the flow-path switching valve which concerns on this invention. The longitudinal cross-sectional view which shows the 2nd flow state (valve body: ascending position) of the flow-path switching valve shown by FIG. The longitudinal cross-sectional view which shows the modification (the 1) of the flow-path switching valve of 2nd Embodiment shown by FIG. (A) is a longitudinal cross-sectional view which shows the deformation | transformation form (the 2) of the flow-path switching valve of 2nd Embodiment shown by FIG. 4, (B) is UA arrow sectional drawing of (A). The longitudinal cross-sectional view which shows the 1st flow state (valve shaft: descending position) of 3rd Embodiment of the flow-path switching valve which concerns on this invention. The longitudinal cross-sectional view which shows the 2nd flow state (valve shaft: ascending position) of the flow-path switching valve shown by FIG. VV arrow sectional drawing of FIG. The longitudinal cross-sectional view which shows the 1st flow state (valve shaft: descending position) of 4th Embodiment of the flow-path switching valve which concerns on this invention. The longitudinal cross-sectional view which shows the 2nd flow state (valve shaft: ascending position) of the flow-path switching valve shown by FIG. The longitudinal cross-sectional view which shows the 1st flow state (valve shaft: descending position) of 5th Embodiment of the flow-path switching valve which concerns on this invention. The longitudinal cross-sectional view which shows the 2nd flow state (valve shaft: ascending position) of the flow-path switching valve shown by FIG. The principal part enlarged view which expands and shows a mode when the valve body in the flow-path switching valve shown by FIG. 13 passes on an inner side port at the time of flow-path switching. The longitudinal cross-sectional view which shows the 1st flow state (valve shaft: descending position) of 6th Embodiment of the flow-path switching valve which concerns on this invention. The longitudinal cross-sectional view which shows the 2nd flow state (valve shaft: ascending position) of the flow-path switching valve shown by FIG. It is a figure which shows the 1st flow state (valve shaft: descending position) of 7th Embodiment of the flow-path switching valve concerning this invention, (A) is a longitudinal cross-sectional view, (B) is X- of (A). X arrow sectional drawing, (C) is the YY arrow sectional drawing of (A). It is a figure which shows the 2nd flow state (valve shaft: raise position) of the flow-path switching valve shown by FIG. 18, (A) is a longitudinal cross-sectional view, (B) is a XX arrow directional cross section of (A). Figure. It is a figure which shows the 1st flow state (valve shaft: descending position) of 8th Embodiment of the flow-path switching valve which concerns on this invention, (A) is a longitudinal cross-sectional view, (B) is X- of (A). X arrow sectional drawing. It is a figure which shows the 2nd flow state (valve shaft: ascending position) of the flow-path switching valve shown by FIG. 20, (A) is a longitudinal cross-sectional view, (B) is a XX arrow cross section of (A). Figure. It is a figure which shows the 3rd flow state (valve shaft: intermediate position) of the flow-path switching valve shown by FIG. 20, (A) is a longitudinal cross-sectional view, (B) is a XX arrow cross section of (A). Figure.

  Hereinafter, an embodiment of a flow path switching valve according to the present invention will be described with reference to the drawings.

[First Embodiment]
1 and 2 are longitudinal sectional views showing a first embodiment of a flow path switching valve according to the present invention. FIG. 1 shows a first flow state (valve shaft: lowered position), and FIG. The flow state (valve shaft: raised position) is shown.

  In this specification, descriptions representing positions and directions such as up and down, left and right, and front and rear are given for the sake of convenience in accordance with the drawings in order to avoid complicated explanation, and the positions and directions in the actual use state. Does not necessarily mean

  In each drawing, the gap formed between the members, the separation distance between the members, etc. are larger than the dimensions of each constituent member for easy understanding of the invention and for convenience of drawing. Or it may be drawn small.

  The flow path switching valve 1 of the present embodiment is an electric multi-way switching valve (in the first embodiment, a four-way switching valve) that switches the flow direction (flow path) of fluid (refrigerant) in multiple directions, for example, in a heat pump air conditioning system or the like. ).

  The flow path switching valve 1 of the illustrated embodiment is mainly composed of a valve body 10 having an outer housing 9B and an inner housing 9A made of a sheet metal cylindrical base (having a constant inner diameter) disposed coaxially. The fixed can 58, the support member 19 fixedly disposed in the valve body 10 in the internal space defined by the valve body 10 and the can 58, and supported by the support member 19 so as to be movable up and down in the internal space. A valve shaft 20 having a valve body (from the upper side, the first valve body 21, the second valve body 22, and the third valve body 23), and a stepping motor attached above the valve body 10 to raise and lower the valve shaft 20 (Elevating drive unit) 50.

  For example, a metal lid-like member 11 is hermetically attached to the lower opening of the outer housing 9B of the valve body 10 by welding, caulking, brazing, or the like. Specifically, the lid-like member 11 has a stepped short columnar shape, as can be understood by referring to FIG. 3 in conjunction with FIG. 1 and FIG. It has a diameter fitting portion 11b and a small diameter protruding portion 11a. The lid-like member 11 is in a state in which the medium diameter fitting portion 11b is airtightly fitted to the lower opening of the inner housing 9A (in other words, the lower opening of the inner housing 9A is airtightly sealed by the medium diameter fitting portion 11b. The lower end of the outer housing 9B is joined by welding or the like to the flange-shaped portion 11d provided at the lower end of the outer periphery of the large-diameter joint 11c, and a cylindrical space is formed inside the inner housing 9A. 7A is defined, and a cylindrical communication space 8A is defined between the inner housing 9A and the outer housing 9B. The small-diameter protruding portion 11a communicates with a through-hole 29a of a connecting shaft 29 of the valve shaft 20 described later (when the valve shaft 20 is in the lowered position) at the center thereof, and slightly from the through-hole 29a. A large-diameter vertical hole 11v is formed, and a plurality of (four in the illustrated example, with 90 ° angular intervals) lateral holes 11u are formed on the side thereof. In addition, here, the upper end of the small-diameter protruding portion 11a abuts against the third valve body 23 to restrict the downward movement (lowering) of the valve shaft 20 when the flow path is switched (in other words, the lowering position of the valve shaft 20). The stopper portion 11s is defined.

  The inner housing 9A disposed inside the outer housing 9B is formed to be slightly thicker than the outer housing 9B, and there are three inner sides arranged in the direction of the axis O (vertical direction) near the center of the side portion. The ports p1, p2, and p3 are opened, and the communication port p11 that communicates with the valve chamber 7A and the communication space 8A is opened above the upper inner port p1, and below the lower inner port p3. A communication port p12 communicating with the valve chamber 7A and the communication space 8A is opened. More specifically, the communication port p11 is positioned above the first valve body 21 when the valve shaft 20 is in the lowered position and below the first valve body 21 when the valve shaft 20 is in the raised position. The communication port p12 is positioned above the third valve body 23 when the valve shaft 20 is in the lowered position and below the third valve body 23 when the valve shaft 20 is in the raised position. While being formed, the communication port p11 and the communication port p12 are opened at the same interval as the interval between the first valve body 21 and the third valve body 23 (details will be described later).

  A laterally facing outer port p10 that opens to the communication space 8A is formed near the center of the side portion of the outer housing 9B. The outer port p10 is always in communication with the communication space 8A.

  In this example, when viewed in a plan view (that is, in the direction of the axis O), the three inner ports p1, p2, and p3 provided apart from each other in the direction of the axis O are formed at the same position, so The ports p11 and p12 are formed at the same position, and are formed on the side opposite to the three inner ports p1, p2 and p3 and the two communication ports p11 and p12 (at an angular interval of 180 °). The outer port p10 is formed on the side opposite to the inner ports p1, p2, and p3 (in other words, on the same side as the two communication ports p11 and p12) when viewed in a plan view.

  Pipe joints # 1, # 2, and # 3 are attached to the three inner ports p1, p2, and p3 sideways by brazing or the like (through the outer housing 9B). A conduit joint # 10 is attached sideways by brazing or the like.

  A stepped cylindrical base 13 is attached to the upper opening of the outer housing 9B of the valve body 10, and the lower surface of the cylindrical base 13 forms the ceiling surface of the communication space 8A. The lower end of a cylindrical can 58 with a ceiling is joined to the upper end of the cylindrical base 13 by welding or the like.

  The support member 19 includes a cylindrical holding member 14 with a bottom wall 14c and a bearing member 15 with an internal thread 15i. The cylindrical holding member 14 is fixed inside the cylindrical base 13 by press-fitting or the like, and is held cylindrical. A cylindrical bearing member 15 in which a female screw 15i is screwed to an inner peripheral lower half portion is fixed to the upper portion of the member 14 by caulking or the like. The bottom wall 14c of the cylindrical holding member 14 is airtightly fitted (internally fitted) into the upper opening of the inner housing 9A, and a cylindrical lifting spring receiver 28 described later is slidably inserted. A cylindrical fitting portion 14b is projected downward. The outer periphery of the bearing member 15 is stepped, and a spring chamber 14a is defined between the cylindrical holding member 14 and the bearing member 15, and the valve shaft 20 is attached to the spring chamber 14a. An energizing compression coil spring 25 is accommodated. A portion of the inner periphery of the bearing member 15 above the female screw 15i is an insertion hole 15a into which a lower base portion of an output shaft 46 of the speed reduction mechanism 40 described later is inserted.

  On the other hand, the stepping motor 50 is disposed inside a can 58 so as to be rotatable with respect to the can 58 and a rotor support member 56. And a rotor 57 fixed inside the upper portion. The stator 55 is externally fixed to the can 58. Further, on the inner peripheral side of the rotor 57, a sun gear 41 formed integrally with the rotor support member 56, and a fixed ring gear 47 fixed to the upper end of the cylindrical body 43 fixed to the upper part of the cylindrical holding member 14. A planetary gear 42 that is disposed 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 shape that meshes with the planetary gear 42 from the outside. Output gear 45, and a strange planetary gear type speed reduction mechanism 40 including an output shaft 46 and the like having an upper fitting portion fixed to a hole formed at the bottom of the output gear 45 by press fitting or the like. Here, the number of teeth of the fixed ring gear 47 is set to be slightly different from the number of teeth of the output gear 45.

  A hole is formed at the center of the upper fitting portion of the output shaft 46, and the lower portion of the support shaft 49 inserted through the center of the sun gear 41 (rotor support member 56) and the carrier 44 is inserted into the hole. . The upper portion of the support shaft 49 has an outer diameter that is substantially the same as the inner diameter of the can 58, and is formed in a hole formed at the center of the support member 48 that is disposed on the upper side of the rotor support member 56 and inscribed in the can 58. It is inserted. The rotor 57 itself does not move up and down inside the can 58 by the support member 48 or the like, and the positional relationship with the stator 55 that is externally fitted and fixed to the can 58 is always maintained constant.

  The lower base portion of the output shaft 46 of the speed reduction mechanism 40 is rotatably inserted into a fitting insertion hole 15a formed in the upper portion of the bearing member 15 with the internal thread 15i, and the center of the lower base portion of the output shaft 46 is centered. A vertically long fitting portion 46a extending in the horizontal direction so as to pass therethrough is formed. A plate-like portion 17c projects from the upper end of the rotary elevating shaft 17 in which a male screw 17a screwed with an internal screw 15i screwed on the inner periphery of the bearing member 15 is provided, and the plate-like portion 17c has a vertically long slit shape. The fitting part 46a is slidably fitted. When the output shaft 46 rotates according to 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 driven by screw feed of the female screw 15 i of the bearing member 15 and the male screw 17 a of the rotary elevating shaft 17. Moves up and down while rotating.

  Below the rotary lift shaft 17, a valve shaft 20 is disposed along the axis O (lifting direction) in which thrust downward of the rotary lift shaft 17 is transmitted through the ball 18 and the ball seat 16. .

  Here, as described above, the compression coil spring 25 housed in the spring chamber 14a above the bottom wall 14c of the cylindrical holding member 14 is disposed with its lower end in contact with the bottom wall 14c. In order to transmit the urging force (lifting force) of the compression coil spring 25 to the valve shaft 20, a cylindrical lifting spring receiving body 28 having a hook-like hook portion on the top and bottom is arranged. The lifting spring receiver 28 is slidably fitted to the bearing member 15 (the lower small diameter portion thereof) and slid to the cylindrical fitting portion 14 b extending downward from the bottom wall 14 c of the cylindrical holding member 14. The upper hook is placed on the upper portion of the compression coil spring 25, and the lower hook is hooked on the valve shaft 20 (the lower end step surface of the large diameter upper portion 27a of the thrust transmission shaft 27). Stopped. That is, the pulling spring receiving body 28 is guided by the bearing member 15 (the lower small diameter portion thereof) and the cylindrical fitting portion 14b of the cylindrical holding member 14 and moves in the axis O direction (up and down direction). The cylindrical holding member 14 is formed with a communication hole 14d that allows the spring chamber 14a and the can 58 to communicate with each other.

  The valve shaft 20 basically includes a stepped cylindrical thrust transmission shaft 27 connected to the rotary elevating shaft 17 via a ball 18 and a ball seat 16 and a thrust transmission shaft 27 (small diameter lower portion 27c). And a cylindrical connecting shaft 29 made of a synthetic resin, which is connected to the connecting shaft 29, and is separated from the connecting shaft 29 in the direction of the axis O by three short columnar valve bodies (first valve body 21, second valve). The body 22 and the third valve body 23) are integrally formed.

  The thrust transmission shaft 27 includes, from above, a large-diameter upper portion 27a into which the ball seat 16 is fitted on the inner periphery, an intermediate body portion 27b inserted into a hook portion formed on the lower side of the lifting spring receiver 28, and a connecting shaft. 29 includes a small-diameter lower portion 27c having a smaller diameter than the intermediate body portion 27b that is fitted into a through-hole 29a provided in the center (along the axis O) and fixed by press-fitting, brazing, or the like. A vertical through hole 27d constituting an upper portion of the communication passage 32 provided in the valve shaft 20 and a plurality of lateral holes 27e opening in the upper back pressure chamber 30 described later are formed. The upper end opening of the through hole 27d is closed by the ball seat 16.

  The connecting shaft 29 is disposed along the vertical direction (axis O direction), and each valve body (the first valve body 21, the second valve body 22, and the third valve body 23) has an inner diameter of the inner housing 9A. And between the valve bodies, the adjacent ports p1-p2 and the p2-p3 of the three inner ports p1-p3 opened in the inner housing 9A are communicated with each other. The connecting shaft 29 is disposed so as to define a space having a size that can be obtained. Further, as described above, the first valve body 21 is positioned below the communication port p11 when the valve shaft 20 is in the lowered position and above the communication port p11 when the valve shaft 20 is in the raised position. The third valve body 23 is disposed on the lower side of the communication port p12 when the valve shaft 20 is in the lowered position and on the upper side of the communication port p12 when the valve shaft 20 is in the raised position. In this way, the connecting shaft 29 is disposed.

  In this example, the first valve body 21 is formed at the upper end portion of the connecting shaft 29, the third valve body 23 is formed at the lower end portion thereof, the second valve body 22 is formed at the upper and lower centers thereof, and the first valve body is formed. The space formed between 21 and the second valve body 22 and the space formed between the second valve body 22 and the second valve body 23 are designed to be substantially the same.

  Further, an annular groove formed on the outer periphery of each valve body (the first valve body 21, the second valve body 22, and the third valve body 23) has a sliding surface clearance between each valve body and the inner housing 9A. The sealing members 21A, 22A, 23A such as O-rings are mounted to seal the inner surface of the sealing member 21 and the outer sides of the sealing members 21A, 22A, 23A to reduce the sliding resistance of the valve elements with respect to the inner housing 9A. Are attached with ring-shaped packings (also referred to as cap seals) 21B, 22B, 23B made of PTFE (Teflon (registered trademark)) or the like.

  Then, the push-down force acting on the valve shaft 20 and the push-up force acting on the valve shaft 20 are balanced (cancel the differential pressure) by the lateral hole 27e and the through-hole 27d of the thrust transmission shaft 27 and the through-hole 29a of the connecting shaft 29. Therefore, an upper back pressure chamber 30 defined above the first valve body 21 in the valve chamber 7A and a lower back pressure chamber 31 defined below the third valve body 23 in the valve chamber 7A are provided. A communication path 32 that is always in communication is configured.

  In the flow path switching valve 1 having such a configuration, when the rotor 57 of the stepping motor 50 is rotationally driven, the rotary lift shaft 17 moves up and down while rotating, but the ball 18 is interposed between the rotary lift shaft 17 and the valve shaft 20. As a result, only the downward thrust is transmitted from the rotary lift shaft 17 to the valve shaft 20 (rotational force is not transmitted), and the rotary lift shaft 17 and the valve shaft 20 are integrally moved up and down in the direction of the axis O. . Here, each valve body (the first valve body 21, the second valve body 22, and the third valve body 23) provided on the valve shaft 20 is brought into contact with the inner housing 9A (the inner periphery thereof), The valve shaft 20 moves up and down in the valve chamber 7A in a state where each valve body (the first valve body 21, the second valve body 22, and the third valve body 23) is inscribed in the inner housing 9A. The communication state (flow direction, flow path) between the inner ports p1, p2, p3 and the outer port p10 is switched.

  That is, when the rotor 57 of the stepping motor 50 is rotationally driven in one direction, the rotation of the rotor 57 is decelerated and transmitted to the rotary lift shaft 17 via the output shaft 46 of the speed reduction mechanism 40, and the female screw 15 i of the bearing member 15 is transmitted. The rotary lift shaft 17 is lowered, for example, while being rotated by screw feed by the male screw 17a of the rotary lift shaft 17, and the valve shaft 20 is pushed down against the urging force of the compression coil spring 25 by the thrust of the rotary lift shaft 17, so that the lowered position is reached. (Here, the third valve body 23 provided at the lower end of the valve shaft 20 is brought into contact with the stopper 11s of the lid-like member 11 and stopped). In this lowered position, the first valve body 21 is positioned between the communication port p11 and the inner port p1, the second valve body 22 is positioned between the inner port p2 and the inner port p3, and the third valve body 23 Is positioned below the communication port p12, and the space between the first valve body 21 and the second valve body 22 is positioned directly beside the inner port p1 and the inner port p2, and the second valve body 22 and the third valve body 22 Since the space between the valve bodies 23 is positioned between the inner port p3 and the communication port p12, the inner port p1 and the inner port p2 pass through the space between the first valve body 21 and the second valve body 22. The inner port p3 and the outer port p10 communicate with each other via the space between the second valve body 22 and the third valve body 23, the communication port p12, and the communication space 8A (first flow state shown in FIG. 1). ).

  On the other hand, when the rotor 57 of the stepping motor 50 is rotationally driven in the other direction, the rotation of the rotor 57 is decelerated and transmitted to the rotary lift shaft 17 via the output shaft 46 of the speed reduction mechanism 40, and the female screw 15i and the male screw 17a are transmitted. For example, the rotary elevating shaft 17 is raised while being rotated by the screw feed, and the valve shaft 20 is raised by the urging force of the compression coil spring 25 to take the raised position. In this raised position, the first valve body 21 is positioned above the communication port p11, the second valve body 22 is positioned between the inner port p1 and the inner port p2, and the third valve body 23 is connected to the inner port p3. The space between the first valve body 21 and the second valve body 22 is positioned between the communication port p12, the space between the communication port p11 and the inner port p1, and the second valve body 22 and the third valve body. 23, since the space between the inner port p2 and the inner port p3 is positioned directly beside the inner port p2 and the inner port p3, the inner port p2 and the inner port p3 communicate with each other via the space between the second valve body 22 and the third valve body 23. Then, the inner port p1 and the outer port p10 communicate with each other via the space between the first valve body 21 and the second valve body 22, the communication port p11, and the communication space 8A (second flow state shown in FIG. 2).

  Here, in the present embodiment, the upper back pressure chamber 30 (the upper portion of the valve chamber 7A) defined on the upper side of the first valve body 21 and the third through the communication passage 32 provided in the valve shaft 20. The lower back pressure chamber 31 (the lower portion of the valve chamber 7A) defined on the lower side of the valve body 23 is always in communication. That is, the upper surface of the first valve body 21 (the surface on the upper back pressure chamber 30 side) and the lower surface of the third valve body 23 (the surface on the lower back pressure chamber 31 side) are equalized, and each valve The surfaces facing each other in the vertical direction of the body (the first valve body 21, the second valve body 22, and the third valve body 23) are also equalized. Therefore, when the flow path is switched by movement of the valve bodies (the first valve body 21, the second valve body 22, and the third valve body 23) in the direction of the axis O, the valve body moves in the direction of movement (the direction of the axis O of the valve shaft 20). The acting force (pressing force acting on the valve body and pushing force) can be balanced (all the differential pressures are canceled).

  Thus, in the present embodiment, the three valve bodies (the first valve body 21, the second valve body 22, and the third valve body 23) provided on the valve shaft 20 are inscribed in the inner housing 9A. Thus, the stepping motor 50 is controlled to raise and lower the valve shaft 20 in the valve chamber 7A, whereby the three inner ports p1, p2, p3 provided in the inner housing 9A and the outer port p10 provided in the outer housing 9B. Since the communication state (flow direction) is switched, the flow direction (flow path) of the fluid can be efficiently switched with a relatively simple configuration, and the uppermost one of the three valve bodies can be switched. Since the upper back pressure chamber 30 above the one valve body 21 and the lower back pressure chamber 31 below the lowermost third valve body 23 are always in communication with each other, the valve body is used when the flow path is switched. As much as possible the acting load And small, can be reduced driving torque of the valve body, has been, further miniaturization, larger capacity, it is also possible to achieve power saving or the like.

  In the present embodiment, the sliding resistance of each valve body with respect to the inner housing 9A is reduced outside the seal members 21A, 22A, and 23A provided on the outer periphery of each valve body (sliding surface with the inner housing 9A). In addition, to suppress the elastic deformation of the seal members 21A, 22A, and 23A (particularly, the elastic deformation that occurs when the seal members 21A, 22A, and 23A pass over the inner ports and the communication port when switching the flow path is suppressed. Packing 21B, 22B made of PTFE (Teflon (registered trademark)) or the like having a relatively high hardness, in order to reduce resistance when the seal members 21A, 22A, 23A pass over the inner ports and the communication ports. , 23B is mounted, so that the load acting on the valve body when switching the flow path can be reduced as much as possible, and the driving torque of the valve body can be reduced more effectively. Can be reduced.

  Furthermore, in the present embodiment, the stepping motor 50 is controlled so that the valve shaft 20 is gradually moved up and down in the valve chamber 7A. For example, from the heating operation to the defrosting operation and from the defrosting operation to the heating. At the time of switching to operation, the pressure difference between the high pressure side and the low pressure side can be reduced, so that noise can be effectively reduced.

[Second Embodiment]
4 and 5 are longitudinal sectional views showing a second embodiment of the flow path switching valve according to the present invention. FIG. 4 shows a first flow state (valve shaft: lowered position), and FIG. The flow state (valve shaft: raised position) is shown.

  The flow path switching valve 2 of the second embodiment is basically the same as the flow path switching valve 1 of the first embodiment with the number of valve bodies formed on the inner port and the valve shaft formed on the inner housing. Only the difference is. Therefore, components having the same functions as those in the first embodiment are denoted by the same reference numerals and detailed description thereof is omitted, and only the differences described above will be described in detail below.

  The flow path switching valve 2 of the present embodiment is used as, for example, a six-way switching valve in a heat pump air conditioning system or the like, and has five side by side in the axis O direction (vertical direction) on the side of the inner housing 9A. The inner ports p1, p2, p3, p4, and p5 are opened, and the communication port p11 that communicates the valve chamber 7A and the communication space 8A is opened above the upper inner port p1, and the lower inner port p5 is opened. A communication port p12 communicating with the valve chamber 7A and the communication space 8A is opened further downward. In addition, each of the inner ports p1, p2, p3, p4, and p5 is provided with conduit joints # 1, # 2, # 3, # 4, and # 5 by brazing or the like (through the outer housing 9B). It is installed sideways.

  In addition, the connecting shaft 29 constituting the valve shaft 20 has four short columnar valve bodies (first valve body 21, second valve body 22, third valve body 23, fourth, spaced apart in the direction of the axis O). A valve body 24) is integrally formed. In this example, the first valve body 21 is formed at the upper end portion of the connecting shaft 29, the fourth valve body 24 is formed at the lower end portion thereof, and each valve body (the first valve body 21, the second valve body 22, the first valve body 24) is formed. The three valve bodies 23 and the fourth valve bodies 24) are arranged at substantially equal intervals in the axis O direction. Also in this example, the annular groove formed on the outer periphery of each valve body (the first valve body 21, the second valve body 22, the third valve body 23, the fourth valve body 24) has a seal such as an O-ring. The members 21A, 22A, 23A, and 24A are mounted, and ring-shaped packings (also referred to as cap seals) made of PTFE (Teflon (registered trademark)) or the like are provided outside the seal members 21A, 22A, 23A, and 24A. 21B, 22B, 23B, and 24B are attached.

  Even in the flow path switching valve 2 configured as described above, when the rotor 57 of the stepping motor 50 is rotationally driven, each valve body (first valve body 21, second valve body 22, third valve body 23, fourth valve body 24). Is in contact with the inner housing 9A, the valve shaft 20 moves up and down in the valve chamber 7A, so that communication between the five inner ports p1, p2, p3, p4, p5 and the outer port p10 (flow) Direction, flow path).

  That is, when the rotor 57 of the stepping motor 50 is rotationally driven in one direction, the valve shaft 20 is in the lowered position (here, the fourth valve body 24 is provided at the lower end portion of the valve shaft 20 as in the first embodiment). In this lowered position, the first valve body 21 is located between the communication port p11 and the inner port p1, and the second valve is stopped. The body 22 is located between the inner port p2 and the inner port p3, the third valve body 23 is located between the inner port p4 and the inner port p5, and the fourth valve body 24 is located below the communication port p12. The space between the first valve body 21 and the second valve body 22 is positioned directly beside the inner port p1 and the inner port p2, and the space between the second valve body 22 and the third valve body 23 is , Located directly beside the inner port p3 and the inner port p4, The space between the valve element 23 and the fourth valve element 24, is caused to position between the inner port p5 and the communication port p12. Accordingly, the inner port p1 and the inner port p2 communicate with each other through the space between the first valve body 21 and the second valve body 22, and the inner port p3 and the inner port p4 are connected to the second valve body 22 and the third valve body 22. The inner port p5 and the outer port p10 communicate with each other through the space between the valve bodies 23, and the space between the third valve body 23 and the fourth valve body 24, the communication port p12, and the communication space 8A. (First flow state shown in FIG. 4).

  On the other hand, when the rotor 57 of the stepping motor 50 is rotationally driven in the other direction, the valve shaft 20 takes the raised position as in the first embodiment. At this raised position, the first valve body 21 is connected to the communication port p11. The second valve element 22 is positioned between the inner port p1 and the inner port p2, the third valve element 23 is positioned between the inner port p3 and the inner port p4, and the fourth valve element. 24 is positioned between the inner port p5 and the communication port p12, and the space between the first valve body 21 and the second valve body 22 is positioned between the communication port p11 and the inner port p1, and the second valve body The space between the second valve body 23 and the third valve body 23 is located directly beside the inner port p2 and the inner port p3, and the space between the third valve body 23 and the fourth valve body 24 is the inner port p4 and the inner port p5. It is positioned right next to As a result, the inner port p2 and the inner port p3 communicate with each other via the space between the second valve body 22 and the third valve body 23, and the inner port p4 and the inner port p5 communicate with the third valve body 23 and the fourth valve body. The inner port p1 and the outer port p10 communicate with each other through the space between the valve bodies 24, and the space between the first valve body 21 and the second valve body 22, the communication port p11, and the communication space 8A. (Second flow state shown in FIG. 5).

  Here, also in the present embodiment, the upper back pressure chamber 30 defined above the first valve body 21 and the lower side of the fourth valve body 24 via the communication passage 32 provided in the valve shaft 20. Since the lower back pressure chamber 31 defined in the above is always in communication, the same effect as the first embodiment can be obtained.

  In this example, the outer port p10 is formed on the side opposite to the inner ports p1, p2, p3, p4, p5 when viewed in plan (in other words, the same side as the two communication ports p11, p12). However, it goes without saying that the positions of the outer port p10, the inner ports p1 to p5, and the communication ports p11 and p12 can be appropriately changed according to the application location of the flow path switching valve 2 and the like. For example, as shown in FIG. 6, the outer port p10 and the inner ports p1 to p5 may be formed on the same side when viewed in a plan view. In the example shown in FIG. 6, the outer port p10 is formed on the upper side of the inner ports p1 to p5, but the outer port p10 may be formed on the lower side of the inner ports p1 to p5. .

  Further, in this example, the cylindrical communication space 8A is formed between the inner housing 9A and the outer housing 9B (outer periphery of the inner housing 9A) by the outer housing 9B and the inner housing 9A made of a cylindrical base disposed coaxially. For example, as shown in FIGS. 7A and 7B, the outer periphery of the inner housing 9A (specifically, the position covering the communication ports p11 and p12 formed in the inner housing 9A). For example, an outer housing 9B composed of a U-shaped housing having a U-shaped cross section is connected (by welding, brazing, etc.), and between the outer housing 9B and an inner housing 9A composed of a cylindrical base (on the outer periphery of the inner housing 9A). A substantially straight communication space 8 </ b> A may be formed in a part). In this case, in the example shown in FIGS. 7A and 7B, the lower end portion of the inner housing 9A is formed between the large-diameter joint portion 11c of the lid-like member 11 and the medium-diameter fitting portion 11b. While being joined to the stepped portion by welding or the like, an enlarged diameter portion 9C is provided at the upper end of the inner housing 9A, and a stepped cylindrical base 13 is attached to the enlarged diameter portion 9C.

[Third Embodiment]
8 and 9 are longitudinal sectional views showing a third embodiment of the flow path switching valve according to the present invention. FIG. 8 shows a first flow state (valve shaft: lowered position), and FIG. The flow state (valve shaft: raised position) is shown.

  The flow path switching valve 3 of the third embodiment basically has an opening position of the outer port and a shape of the communication space between the outer housing and the inner housing with respect to the flow path switching valve 2 of the second embodiment. It is different. Therefore, components having the same functions as those of the second embodiment are denoted by the same reference numerals and detailed description thereof is omitted, and only the differences described above will be described in detail below.

  Similarly to the second embodiment, the flow path switching valve 3 of the present embodiment is used as a six-way switching valve in, for example, a heat pump air conditioning system, and the outer diameter of the inner housing 9A is equal to the inner diameter of the outer housing 9B. The inner housing 9A is fitted into the outer housing 9B and is formed on the outer periphery of the inner housing 9A (specifically, the portion where the communication ports p11 and p12 are formed) (in the vertical direction) D. A cut surface 9D is formed, and the communication space 8A is formed by the D cut surface 9D and the inner peripheral surface of the outer housing 9B (see also FIG. 10).

  In this example, a seal member 14A made of an O-ring or the like is interposed between the upper opening of the inner housing 9A and the cylindrical fitting portion 14b provided on the cylindrical holding member 14 (the bottom wall 14c). It is disguised.

  The outer port p10 is formed above the inner ports p1 to p5 in the outer housing 9B and at substantially the same height as the communication port p11, and is provided in the inner housing 9A so as to be connected to the outer port p10. Through the opening p10a and the communication port p11, the communication space 8A is always in communication.

  Even in the flow path switching valve 3 having such a configuration, when the rotor 57 of the stepping motor 50 is rotationally driven, each valve body (first valve body 21, second valve body 22, third valve body 23, fourth valve body 24). Is in contact with the inner housing 9A, the valve shaft 20 moves up and down in the valve chamber 7A, so that communication between the five inner ports p1, p2, p3, p4, p5 and the outer port p10 (flow) Direction, flow path).

  That is, when the rotor 57 of the stepping motor 50 is rotationally driven in one direction, the valve shaft 20 is moved to the lowered position (here, the fourth valve body 24 is provided at the lower end portion of the valve shaft 20 as in the second embodiment). The position where the first valve element 21 is connected to the communication port p11 and the outer port p10 and the inner port p1 is in this lowered position. The second valve element 22 is positioned between the inner port p2 and the inner port p3, the third valve element 23 is positioned between the inner port p4 and the inner port p5, and the fourth valve element 24 Is positioned below the communication port p12, and the space between the first valve body 21 and the second valve body 22 is positioned directly beside the inner port p1 and the inner port p2, and the second valve body 22 and the third valve body 22 The space between the valve bodies 23 is the inner port Located just beside the p3 and inner port p4, the space between the third valve body 23 of the fourth valve element 24, is caused to position between the inner port p5 and the communication port p12. Accordingly, the inner port p1 and the inner port p2 communicate with each other through the space between the first valve body 21 and the second valve body 22, and the inner port p3 and the inner port p4 are connected to the second valve body 22 and the third valve body 22. The inner port p5 and the outer port p10 communicate with each other through the space between the valve bodies 23, the space between the third valve body 23 and the fourth valve body 24, the communication port p12, the communication space 8A, the communication port p12, The upper back pressure chamber 30 above the first valve body 21 communicates with the opening p10a (first flow state shown in FIG. 8).

  On the other hand, when the rotor 57 of the stepping motor 50 is rotationally driven in the other direction, the valve shaft 20 takes the raised position as in the second embodiment. At this raised position, the first valve body 21 is connected to the communication port p11. And the second valve element 22 is located between the inner port p1 and the inner port p2, and the third valve element 23 is located between the inner port p3 and the inner port p4. The fourth valve body 24 is positioned between the inner port p5 and the communication port p12, and the space between the first valve body 21 and the second valve body 22 is defined as the communication port p11 and the opening p10a and the inner port. p1 and the space between the second valve element 22 and the third valve element 23 is located directly beside the inner port p2 and the inner port p3, and between the third valve element 23 and the fourth valve element 24. The inner space is inside port p4 and inside It is caused to position just beside the over door p5. As a result, the inner port p2 and the inner port p3 communicate with each other via the space between the second valve body 22 and the third valve body 23, and the inner port p4 and the inner port p5 communicate with the third valve body 23 and the fourth valve body. The inner port p1 and the outer port p10 communicate with each other through a space between the valve bodies 24, and a space between the first valve body 21 and the second valve body 22 (second flow shown in FIG. 9). State).

  Here, also in the present embodiment, the upper back pressure chamber 30 defined above the first valve body 21 and the lower side of the fourth valve body 24 via the communication passage 32 provided in the valve shaft 20. Since the lower back pressure chamber 31 defined in the above is always in communication, the same effect as the first and second embodiments can be obtained.

  In this example, the outer port p10 is formed above the inner ports p1 to p5 in the outer housing 9B and at substantially the same height as the communication port p11. For example, the outer port p10 is connected to the outer housing 9B. Needless to say, it may be formed below the inner ports p1 to p5 at approximately the same height as the communication port p12 so as to always communicate with the communication space 8A via the communication port p12.

[Fourth Embodiment]
FIGS. 11 and 12 are longitudinal sectional views showing a fourth embodiment of the flow path switching valve according to the present invention. FIG. 11 shows a first flow state (valve shaft: lowered position), and FIG. The flow state (valve shaft: raised position) is shown.

  The flow path switching valve 4 of the fourth embodiment is basically a communication path that constantly communicates the upper back pressure chamber 30 and the lower back pressure chamber 31 with respect to the flow path switching valve 2 in the second embodiment. The configuration of 32 is different. Therefore, components having the same functions as those of the second embodiment are denoted by the same reference numerals and detailed description thereof is omitted, and only the differences described above will be described in detail below.

  The flow path switching valve 4 of the present embodiment is used as a six-way switching valve in, for example, a heat pump air conditioning system or the like, similar to the second embodiment, and here, the connecting shaft 29 constituting the valve shaft 20 is The small-diameter lower portion 27c of the stepped cylindrical thrust transmission shaft 27 is inserted into a center hole 29b formed in the upper end portion of the connection shaft 29 and is connected by press fitting, brazing, or the like.

  Further, the cylindrical fitting member 14b provided on the cylindrical holding member 14 (the bottom wall 14c thereof) is formed to be slightly longer, and the cylinder is formed so that a gap is provided between the bottom wall 14c and the upper end portion of the inner housing 9A. The cylindrical fitting portion 14b is fitted (internally fitted) into the upper opening of the inner housing 9A, and the upper portion of the cylindrical fitting portion 14b (specifically, corresponds to the gap in the cylindrical fitting portion 14b). A lateral hole 32a is formed in the portion. The lateral hole 32a may be formed above the communication port p11 in the inner housing 9A and above the first valve body 21 when the valve shaft 20 is in the raised position.

  Further, a lateral hole 32b is formed in the inner housing 9A below the communication port p12 and on the side of the small-diameter protruding portion 11a of the lid-like member 11 (that is, the portion corresponding to the lower back pressure chamber 31). Yes.

  Thereby, in the flow path switching valve 4 of the present embodiment, the space between the horizontal hole 32a of the cylindrical fitting portion 14b of the cylindrical holding member 14, the upper end portion of the inner housing 9A, and the bottom wall 14c of the cylindrical holding member 14 is determined. The upper back pressure chamber 30 and the lower side are formed by the communication space 8A between the inner housing 9A and the outer housing 9B (in other words, the outer side of the inner housing 9A) including the gap formed in the inner housing 9A and the lateral hole 32b of the inner housing 9A. A communication path 32 that always communicates with the side back pressure chamber 31 is configured.

  Even in the flow path switching valve 4 having such a configuration, when the rotor 57 of the stepping motor 50 is rotationally driven, each valve body (first valve body 21, second valve body 22, third valve body 23, fourth valve body 24). As the valve shaft 20 moves up and down in the valve chamber 7A with the inner housing 9A being inscribed in the inner housing 9A, the five inner ports p1, p2, p3, p4, p5, and Although the communication state (flow direction, flow path) between the outer ports p10 is switched, the upper side of the first valve body 21 is connected via the communication passage 32 including the communication space 8A between the inner housing 9A and the outer housing 9B. Since the upper back pressure chamber 30 defined at the bottom and the lower back pressure chamber 31 defined at the lower side of the fourth valve body 24 are always in communication, the first, second, and third implementations described above are performed. The same effect as the form can be obtained.

  Moreover, in this embodiment, since the through-hole in the connection shaft 29 which comprises the valve shaft 20 can be abbreviate | omitted, there also exists an effect that valve shaft 20 itself can also be set as a comparatively simple structure.

  In this case, the upper back pressure chamber 30 and the lower back pressure chamber 31 are always in communication with each other via the communication path 32 including the communication space 8A and the like outside the inner housing 9A. One of the ports p11 and p12 may be omitted, or a communication port that connects the valve chamber 7A and the communication space 8A may be formed at a position different from the communication ports p11 and p12.

[Fifth Embodiment]
FIGS. 13 and 14 are longitudinal sectional views showing a fifth embodiment of the flow path switching valve according to the present invention. FIG. 13 shows a first flow state (valve shaft: lowered position), and FIG. The flow state (valve shaft: raised position) is shown.

  The flow path switching valve 5 of the fifth embodiment is basically the same as the flow path switching valve 4 of the fourth embodiment of the inner ports p1 to p5 and the communication ports p11 and p12 formed in the inner housing 9A. The shape near the inner circumference is different. Therefore, components having the same functions as those in the fourth embodiment are denoted by the same reference numerals and detailed description thereof is omitted, and only the differences described above will be described in detail below.

  The flow path switching valve 5 of the present embodiment is used as a six-way switching valve in, for example, a heat pump type air conditioning system or the like, as in the fourth embodiment. Here, the connecting shaft 29 constituting the valve shaft 20 is a connecting shaft 29. It is comprised from three 1st connection shaft structure bodies 29A-29C and one 2nd connection shaft structure body 29D.

  A short columnar valve body (first valve body 21, second valve body 22, third valve body 23) is integrally formed at the upper end of each of the first connecting shaft constituting bodies 29A to 29C, Small-diameter fitting insertion portions 29Aa to 29Ca having the same shape as the small-diameter lower portion 27c of the thrust transmission shaft 27 are formed at the lower end portion. In addition, a short cylindrical valve body (fourth valve body 24) is integrally formed at the upper end portion of the second connecting shaft constituting body 29D.

  A small-diameter lower portion 27c of the thrust transmission shaft 27 is fitted from above to a center hole 29Ab formed in the upper end portion of the first connecting shaft constituting body 29A, and is integrally connected by press fitting, brazing, or the like. The small-diameter fitting insertion portion 29Aa of the first connecting shaft constituting body 29A is fitted from above and integrally connected to the center hole 29Bb formed in the upper end portion of the constituting body 29B, and the upper end of the first connecting shaft constituting body 29C. A small-diameter fitting portion 29Ba of the first connecting shaft constituting body 29B is fitted from above and integrally connected to the center hole 29Cb formed in the portion, and is formed at the upper end portion of the second connecting shaft constituting body 29D. The small-diameter fitting insertion portion 29Ca of the first connecting shaft constituting body 29C is fitted and integrally connected to the center hole 29Db from above, so that it is distributed along the axis O direction and in the axis O direction. 4 valve bodies (first valve body spaced apart) 1, the second valve body 22, the third valve body 23, a fourth the valve shaft 20 to the valve body 24) is provided is configured.

  Further, here, when the small diameter lower portion 27c is press-fitted between the upper end surface of the first valve body 21 of the first connecting shaft constituting body 29A and the lower end step surface of the intermediate body portion 27b of the thrust transmission shaft 27, the pressing member 21C. Is inserted and fixed, and the first valve body 21 (the outer peripheral surface thereof) and the inner housing 9 </ b> A ( The seal member 21A for sealing (the sliding surface gap formed between) is attached to the inner peripheral surface), and is formed of PTFE (Teflon (registered trademark)) or the like outside the seal member 21A. The packing 21B is attached.

  Further, between the second valve body 22 of the first connecting shaft constituting body 29B and the first connecting shaft constituting body 29A, between the third valve body 23 of the first connecting shaft constituting body 29C and the first connecting shaft constituting body 29B. Similarly, the pressing members 22C to 24C are sandwiched and fixed between the fourth valve body 24 and the first connecting shaft constituting body 29C of the second connecting shaft constituting body 29D. The seal members 22A to 24A and the packings 22B to 24B are mounted in an annular groove formed by the members 22C to 24C and the second to fourth valve bodies 22 to 24.

  Further, in the present embodiment, the portions where the inner ports p1 to p5 and the communication ports p11 and p12 are formed on the inner periphery of the inner housing 9A are formed in a concave shape over the entire periphery (concave surface portions s1 to s5, s11, s12) (also referred to as recess processing), and tapered surface portions t1 to t5, t11, and t12 each having a truncated cone surface are provided on the upper and lower surfaces of the concave surface portions s1 to s5, s11, and s12.

  In the illustrated example, the tapered surface portions t1 to t5, t11, and t12 are formed of a truncated cone surface and have a straight shape when viewed in a longitudinal section. For example, the tapered surface portions t1 to t5, t11, and t12 are Alternatively, it may be formed in a curved shape that is convex inward or convex outward when viewed in a longitudinal section. Further, the boundary portions between the inner ports p1 to p5 and the communication ports p11 and p12 and the inner housing 9A, or the boundary portions between the tapered surface portions t1 to t5, t11 and t12 and the inner housing 9A may be rounded.

  Even in the flow path switching valve 5 having such a configuration, when the rotor 57 of the stepping motor 50 is rotationally driven, each valve body (first valve body 21, second valve body 22, third valve body 23, fourth valve body 24). As the valve shaft 20 moves up and down in the valve chamber 7A with the inner housing 9A being inscribed in the inner housing 9A, the five inner ports p1, p2, p3, p4, p5, and Although the communication state (flow direction, flow path) between the outer ports p10 is switched, the communication path 32 including the communication space 8A between the inner housing 9A and the outer housing 9B (in other words, outside the inner housing 9A) is provided. The upper back pressure chamber 30 defined on the upper side of the first valve body 21 and the lower back pressure chamber 31 defined on the lower side of the fourth valve body 24 are always in communication with each other. The same effect as the fourth embodiment can be obtained.

  Further, in the present embodiment, concave portions s1 to s5, s11, and s12 are provided over the entire circumference in the portion where the inner ports p1 to p5 and the communication ports p11 and p12 are formed on the inner periphery of the inner housing 9A. Therefore, the outer periphery of each valve body (including packings 21B, 22B, 23B, 24B and seal members 21A, 22A, 23A, 24A provided on the outer periphery of each valve body) and the inner housing 9A at the time of switching the flow path Since the sliding resistance with the circumference can be reduced, the load acting on the valve body when switching the flow path can be reduced as much as possible, and the driving torque of the valve body can be reduced more effectively.

  Further, PTFE (Teflon) having a relatively high hardness is provided on the outer side of the seal members 21A, 22A, 23A, and 24A provided on the outer periphery of each valve body so as to suppress elastic deformation of the seal members 21A, 22A, 23A, and 24A. (Registered Trademark)) or other packings 21B, 22B, 23B, 24B are mounted, but elastic when the seal members 21A, 22A, 23A, 24B pass over the respective inner ports and communication ports when the flow path is switched. There is a possibility that the outer peripheral portions of the packings 21B, 22B, 23B, and 24B and the seal members 21A, 22A, 23A, and 24A protrude from the annular grooves formed on the outer periphery of each valve body by being deformed. In the present embodiment, taper surface portions t1 to t5, t11, and t12 each having a truncated cone surface are formed on (in the upper and lower portions of) the inner ports p1 to p5 and the communication ports p11 and p12 on the inner periphery of the inner housing 9A. For example, as shown in an enlarged view in FIG. 15, the packings 21B, 22B, 23B, and 24B and the seal members 21A, 22A, 23A, and 24A smoothly move on the inner ports and the communication ports when the flow path is switched. Resistance when the packings 21B, 22B, 23B, 24B and the sealing members 21A, 22A, 23A, 24A pass over the inner ports and the communication ports (in the illustrated example, the inner ports and the communication ports) Can further reduce the resistance caused by the step between the concave surface provided in the portion formed with the inner periphery of the inner housing. Because, this also, the flow path switching can be reduced as much as possible the loads acting on the valve element, can be further effectively reduce the driving torque of the valve body.

[Sixth Embodiment]
16 and 17 are longitudinal sectional views showing a sixth embodiment of the flow path switching valve according to the present invention. FIG. 16 shows a first flow state (valve shaft: lowered position), and FIG. The flow state (valve shaft: raised position) is shown.

  The flow path switching valve 6 according to the sixth embodiment is basically the same as the flow path switching valve 1 according to the first embodiment, except that the number of valve bodies formed on the inner port and the valve shaft is formed on the inner housing. Is different. Therefore, components having the same functions as those in the first embodiment are denoted by the same reference numerals and detailed description thereof is omitted, and only the differences described above will be described in detail below.

  The flow path switching valve 6 of this embodiment is used as, for example, a three-way switching valve in a heat pump air conditioning system or the like, and two side by side in the axis O direction (vertical direction) are arranged on the side of the inner housing 9A. The inner ports p1, p2 are opened, and the communication port p11 communicating with the valve chamber 7A and the communication space 8A is opened above the upper inner port p1, and the valve is opened below the lower inner port p2. A communication port p12 that communicates between the chamber 7A and the communication space 8A is opened. More specifically, the communication port p11 is formed so as to be positioned above the first valve body 21 when the valve shaft 20 is in the raised position, and the communication port p12 is formed when the valve shaft 20 is in the lowered position. It is formed so as to be located below the second valve body 22. That is, here, the communication port p11 is formed so as to be always located above the first valve body 21, and the communication port p12 is formed so as to be always located below the second valve body 22. Pipe joints # 1 and # 2 are attached to the inner ports p1 and p2 sideways by brazing or the like (through the outer housing 9B).

  Further, the intermediate body portion 27b of the thrust transmission shaft 27 constituting the valve shaft 20 is formed to be slightly longer, and the connecting shaft 29 coupled to the thrust transmission shaft 27 (the smaller diameter lower portion 27c) is spaced apart in the axis O direction. Thus, two short cylindrical valve bodies (first valve body 21 and second valve body 22) are integrally formed. Each valve body (the first valve body 21 and the second valve body 22) is separated by approximately the same distance as the hole diameters of the two inner ports p1 and p2 opened in the inner housing 9A. Between the valve bodies, the connecting shaft 29 is disposed so as to define a space having a size communicating with one of the two inner ports p1 and p2 opened in the inner housing 9A. . Further, the first valve body 21 is located between the two inner ports p1, p2 when the valve shaft 20 is in the lowered position and between the inner port p1 and the communication port P11 when the valve shaft 20 is in the raised position. The second valve element 22 is disposed between the inner port p2 and the communication port p12 when the valve shaft 20 is in the lowered position and when the valve shaft 20 is in the raised position. The connecting shaft 29 is disposed between the two inner ports p1 and p2.

  In this example, the first valve body 21 is formed at the upper end portion of the connecting shaft 29, and the second valve body 22 is formed at the lower end portion thereof. Also in this example, seal members 21A and 22A such as O-rings are mounted on the annular grooves formed on the outer periphery of each valve body (first valve body 21 and second valve body 22), and each seal Ring-shaped packings (also referred to as cap seals) 21B and 22B made of PTFE (Teflon (registered trademark)) or the like are mounted on the outside of the members 21A and 22A.

  Even in the flow path switching valve 6 having such a configuration, when the rotor 57 of the stepping motor 50 is rotationally driven, each valve body (the first valve body 21 and the second valve body 22) is in contact with the inner housing 9A. As the valve shaft 20 moves up and down in the valve chamber 7A, the communication state (flow direction, flow path) between the two inner ports p1, p2 and the outer port p10 is switched.

  That is, when the rotor 57 of the stepping motor 50 is rotationally driven in one direction, the valve shaft 20 is in the lowered position (here, the second valve body 22 provided at the lower end portion of the valve shaft 20 is the same as in the first embodiment). In this lowered position, the first valve body 21 is located between the inner port p1 and the inner port p2, and the second valve is stopped. The body 22 is positioned between the inner port p2 and the communication port p12, and the space between the first valve body 21 and the second valve body 22 is positioned directly beside the inner port p2. As a result, the inner port p1 and the outer port p10 communicate with each other via the space above the first valve body 21 (upper back pressure chamber 30), the communication port p11, and the communication space 8A in the valve chamber 7A, and the valve chamber 7A. A space above the first valve body 21 (upper back pressure chamber 30), a communication path 32A provided in the valve shaft 20 (a lateral hole 27e and a through hole 27d of the thrust transmission shaft 27, a through hole 29a of the connecting shaft 29). ), The vertical hole 11v and the horizontal hole 11u of the lid-like member 11 (its small-diameter protruding portion 11a), the space below the second valve body 22 in the valve chamber 7A (lower back pressure chamber 31), the communication port p12, It communicates via the communication space 8A (first flow state shown in FIG. 16).

  On the other hand, when the rotor 57 of the stepping motor 50 is rotationally driven in the other direction, the valve shaft 20 takes the raised position as in the first embodiment. At this raised position, the first valve body 21 is connected to the communication port p11. The second valve body 22 is positioned between the inner port p1 and the inner port p2, and the space between the first valve body 21 and the second valve body 22 is located on the inner side. It is positioned right next to the port p1. As a result, the inner port p2 and the outer port p10 communicate with each other via the space below the second valve body 22 (lower back pressure chamber 31), the communication port p12, and the communication space 8A in the valve chamber 7A. The space below the second valve body 22 in the chamber 7A (lower back pressure chamber 31), the communication path 32A provided in the valve shaft 20 (the lateral hole 27e and the through hole 27d of the thrust transmission shaft 27, the connecting shaft 29) Through hole 29a), a space above the first valve body 21 in the valve chamber 7A (upper back pressure chamber 30), a communication port p11, and a communication space 8A (second flow state shown in FIG. 17).

  Here, also in this embodiment, the communication path 32B including the communication path 32A provided in the valve shaft 20 and the communication space 8A between the inner housing 9A and the outer housing 9B (in detail, the inner housing 9A). The upper side defined on the upper side of the first valve body 21 through the two communication ports p11, p12 and the communication path 32B formed by the communication space 8A between the inner housing 9A and the outer housing 9B. Since the back pressure chamber 30 and the lower back pressure chamber 31 defined on the lower side of the second valve body 22 are always in communication, the same effects as those of the first embodiment can be obtained.

  In this case, the upper back pressure chamber 30 and the lower back pressure chamber 31 are always in communication with each other via the communication path 32B including the communication space 8A on the outside of the inner housing 9A. Of course, the communication passage 32A provided in the valve shaft 20 may be omitted, for example, by forming the connecting shaft 29 constituting the valve shaft 20 substantially solid.

  In addition, by adopting the same configuration as the flow path switching valve 6 of the sixth embodiment, a flow path switching valve that switches the flow direction (flow path) of fluid (refrigerant) such as a five-way switching valve to an odd number direction. Needless to say, it can be configured.

[Seventh Embodiment]
18 and 19 are views showing a seventh embodiment of the flow path switching valve according to the present invention. FIG. 18 shows a first flow state (valve shaft: lowered position), and FIG. 19 shows a second flow state. (Valve shaft: ascending position). In this example, the axis O of the valve body 10 and the center line (rotation axis) L of the stepping motor 50 are set so as to be shifted due to the positional relationship of twist (details will be described later). FIGS. 19A and 19A are cross-sectional views taken along the line Z-z1-z2-Z in FIG. 18C.

  The flow path switching valve 7 according to the seventh embodiment is basically the same as the flow path switching valve 5 according to the fifth embodiment with the number of valve bodies formed on the inner port and the valve shaft formed on the inner housing. The configuration of the lid-like member attached to the lower opening of the outer housing, the arrangement configuration of the stepping motor that configures the elevating drive unit, and the configuration of each part associated therewith are different. Therefore, components having the same functions as those in the fifth embodiment are denoted by the same reference numerals and detailed description thereof is omitted, and only the differences described above will be described in detail below.

  The flow path switching valve 7 of the present embodiment is used as, for example, a four-way switching valve in a heat pump air conditioning system or the like, and has three side by side in the axis O direction (vertical direction) on the side of the inner housing 9A. The inner ports p1, p2, and p3 are opened, and the communication port p11 that communicates with the valve chamber 7A and the communication space 8A is opened above the upper inner port p1, and below the lower inner port p3. A communication port p12 that communicates the valve chamber 7A and the communication space 8A is opened. In addition, conduit joints # 1, # 2, and # 3 are attached to the inner ports p1, p2, and p3 sideways by brazing or the like (through the outer housing 9B).

  The connecting shaft 29 constituting the valve shaft 20 includes two first connecting shaft constituting bodies 29A and 29B and one second connecting shaft constituting body 29C, and each first connecting shaft constituting body 29A, A short cylindrical valve body (first valve body 21 and second valve body 22) is integrally formed at the upper end portion of 29B, and a short cylindrical shape is formed at the upper end portion of the second connecting shaft constituting body 29C. A valve body (third valve body 23) is integrally formed, and three valve bodies (first valve body 21, second valve body 22, and third valve body 23) are separated in the direction of the axis O and are short cylindrical. Is distributed. Also in this example, seal members 21A, 22A, and 23A are attached to the annular grooves formed on the outer periphery of each valve body (the first valve body 21, the second valve body 22, and the third valve body 23). In addition, packings 21B, 22B, and 23B made of PTFE (Teflon (registered trademark)) or the like are attached to the outside of the seal members 21A, 22A, and 23A.

  It should be noted that the number of inner ports and valve bodies is different from the flow path switching valve 5 of the fifth embodiment (the number of inner ports is changed from five to three, and the number of valve bodies is changed from four. Regarding the points that are changed to three), refer also to the first and second embodiments shown in FIGS.

  Here, the lid-like member 11 attached to the lower opening of the outer housing 9B includes a short cylindrical outer peripheral member 11A in which an outer fitting portion 11Ab that is extrapolated to the lower portion of the inner housing 9A is projected (upward), It has a two-part configuration including an inner peripheral member 11B having a convex cross section that is inserted and fixed to the outer peripheral member 11A. The lid-like member 11 has an outer fitting portion 11Ab of the outer peripheral member 11A extrapolated to the lower portion of the inner housing 9A, and an upper protruding portion 11Ba of the inner peripheral member 11B is inserted into the lower opening of the inner housing 9A (with a predetermined gap). In the inserted state, the lower end portion of the outer housing 9B is joined to the flange-shaped portion 11Ad provided at the lower end of the outer periphery of the outer peripheral member 11A by welding or the like. The upper end of the upper projecting portion 11Ba of the inner peripheral member 11B abuts against the third valve body 23 to restrict the downward movement (downward movement) of the valve shaft 20 when the flow path is switched (in other words, the valve shaft 20 The stopper portion 11Bs defines the lowered position.

  Further, in the present embodiment, the upper opening of the outer housing 9B of the valve body 10 is joined to the short cylindrical joint portion 13Aa to which the upper end portion of the outer housing 9B is joined, and is substantially long in the vertical direction (axis O direction). A base member 13A composed of a quadrangular columnar base portion 13Ac is attached, and the lower surface of the base member 13A (joint portion 13Aa thereof) forms the ceiling surface of the communication space 8A. A lower surface of the base member 13A is airtightly fitted (internally fitted) into the upper opening of the inner housing 9A, and a thrust transmission shaft 27 (a large-diameter upper portion 27a) described later is slidably inserted. The cylindrical fitting portion 13Ab protrudes downward, and a horizontal hole 32a (with the inner housing 9A) is formed in an upper portion of the cylindrical fitting portion 13Ab (that is, a portion adjacent to the lower surface of the base member 13A). The communication space 8A between the outer housing 9B and the lateral hole 32b of the inner housing 9A, as well as a hole that forms a communication path 32 that always communicates the upper back pressure chamber 30 and the lower back pressure chamber 31) are formed. ing.

  Further, the large-diameter upper portion 27a (in this example, which is not provided with a ball seat and is solid) of the thrust transmission shaft 27 constituting the valve shaft 20 is formed relatively long in the vertical direction. The base member 13A (inside) is provided with a vertical hole 13Av into which the large-diameter upper portion 27a is inserted from below and is slidably disposed in the axis O direction (vertical direction). On the outer periphery of the upper portion of the large-diameter upper portion 27a (a part of the outer periphery of the portion inserted into the vertical hole 13Av) is a driven tooth 62 as a rack gear that constitutes one of the rack-and-pinion type motion conversion mechanisms 60 described later (in the vertical direction). For a predetermined length).

  Further, in the present embodiment, the stepping motor 50 that constitutes the lifting drive unit lies sideways on the side of the base member 13A (the base portion 13Ac) of the valve body 10 (in other words, when viewed from the side, A center line (rotation axis of the rotor 57) L of the stepping motor 50 is attached (in a state where the center line L is perpendicular to the axis O of the valve body 10).

  The configuration itself of the stepping motor 50 and the strange planetary gear speed reduction mechanism 40 is the same as that described above except that it is changed from vertical installation (arrangement of the center line in the vertical direction) to horizontal installation (arrangement of the center line in the horizontal direction). Although it is substantially the same as the stepping motor 50 and the mysterious planetary gear type reduction mechanism 40 of the flow path switching valves 1 to 6 in the first to sixth embodiments, here, the stepped cylindrical holding member 14 is connected to the reduction mechanism 40. A (cylindrical) bearing member 15 (in this example, which is not provided with a female thread portion) having a fitting hole 15a into which the lower base portion of the output shaft 46 is fitted is fixed by caulking or the like. The cylindrical holding member 14 includes, from the stepping motor 50 side, a small-diameter portion 14e, an intermediate body portion 14f, and a large-diameter portion 14g that are fitted and fixed to the bearing member 15 and to which the cylindrical body 43 of the speed reduction mechanism 40 is fixed. The ring-shaped member 14h is fitted and fixed to the step portion 14s formed between the small-diameter portion 14e and the intermediate body portion 14f by press-fitting or the like. Are joined by welding or the like. Further, the intermediate barrel portion 14f of the cylindrical holding member 14 has a locking portion facing inward to fix the cylindrical holding member 14 to the base member 13A (base portion 13Ac) of the valve body 10. A mounting member 14i having a cylindrical shape (a cylindrical shape having a diameter larger than that of the intermediate body portion 14f by the thickness of a connecting portion 13Ad of a base member 13A to be described later) is provided with a projecting portion 14j and a female screw portion formed on the inner periphery. It is extrapolated (slidable in the direction of the center line L).

  On the inner side of the support member 19 composed of the bearing member 15 and the cylindrical holding member 14, a plate shape that is fitted into a slit-like fitting portion 46 a formed in the lower base portion of the output shaft 46 of the speed reduction mechanism 40. A stepped rotation shaft 17 having a portion 17c (in this example, no male screw portion is provided) is disposed. The rotating shaft 17 rotates around a center line (rotating axis) L but is prevented from moving in the direction of the center line L, and is disposed inside the support member 19 (details will be described later). Further, the rotary shaft 17 (the end opposite to the end provided with the plate-like portion 17 c) has a base of the valve main body 10 when the cylindrical holding member 14 is attached to the valve main body 10. A serration shaft portion 17e to be inserted into the inside of the base member 13A (a lateral hole 13Au to be described later) is provided. A drive tooth 61 as a pinion gear constituting one of a rack and pinion type motion converting mechanism 60 described later is formed on the outer periphery of the tip end portion of the serration shaft portion 17e.

  On the other hand, on one side surface of the base portion 13Ac of the base member 13A of the valve body 10 (in this example, the side surface on the same side as the conduit joints # 1, # 2, and # 3 when viewed in a plan view) Is substantially the same as the large-diameter portion 14g of the cylindrical holding member 14, and a cylindrical connecting portion 13Ad having a male screw portion formed on the outer periphery thereof is projected, and the center of the cylindrical connecting portion 13Ad is Further, a horizontal hole 13Au into which the serration shaft portion 17e of the rotating shaft 17 is inserted is provided. Here, the center line of the cylindrical connecting portion 13Ad and the lateral hole 13Au (that is, the center line of the stepping motor 50 (rotation axis of the rotor 57) L) is a torsional positional relationship with respect to the axis O of the valve body 10 ( The horizontal hole 13Au (extending in the horizontal direction) and the vertical hole 13Av (extending in the vertical direction) are formed so as to partially overlap each other (in particular, FIG. 18C). )reference). As a result, the drive teeth 61 provided on the serration shaft portion 17e of the rotary shaft 17 inserted in the lateral hole 13Au are connected to the driven teeth 62 provided on the large diameter upper portion 27a of the thrust transmission shaft 27 inserted in the vertical hole 13Av. Are designed to mesh. By the drive teeth 61 provided on the rotary shaft 17 and the driven teeth 62 provided on the thrust transmission shaft 27 of the valve shaft 20, the rotary motion (in both forward and reverse directions) of the rotary shaft 17 is moved up and down ( A motion conversion mechanism 60 that converts to a reciprocating linear motion) is configured (rack and pinion type), and the valve shaft 20 is moved in the axis O direction (longitudinal direction) by the stepping motor 50, the rotary shaft 17, the motion conversion mechanism 60, and the like. ) Is configured to move up and down.

  The serration shaft portion 17e of the rotating shaft 17 is inserted into the horizontal hole 13Au, and the large-diameter portion 14g of the cylindrical holding member 14 is inserted into the cylindrical connecting portion 13Ad for positioning, and provided at the connecting portion 13Ad. By screwing a female thread portion provided on a mounting member 14i externally inserted into the intermediate body portion 14f of the cylindrical holding member 14 into the male screw portion, the large-diameter portion 14g (of the cylindrical holding member 14) The locking portion 14j (the inner end) of the mounting member 14i comes into contact with the stepped portion 14t), and the large-diameter portion 14g has a base portion 13Ac (the side surface) of the base member 13A and the locking portion 14j of the mounting member 14i. With respect to the base member 13A (base portion 13Ac) of the valve main body 10, the stepping motor 50, the mysterious planetary gear speed reduction mechanism 40, the support member 19 (the cylindrical holding member 14 and the bearing member 15) are supported. ) The assembly consisting of the rotating shaft 17, etc. are fixed assembled. In addition, between the large-diameter portion 14g (the end surface thereof) of the cylindrical holding member 14 and the base portion 13Ac (the side surface) of the base member 13A (specifically, the lateral hole 13Au on the side surface of the base portion 13Ac of the base member 13A) An O-ring 13Ae as a sealing material is interposed in an annular groove formed around.

  In this example, the diameter of the vicinity of the opening end of the horizontal hole 13Au and the vicinity of the opening end (opening end of the insertion hole for inserting the rotating shaft 17) in the large-diameter portion 14g of the cylindrical holding member 14 are increased. In addition, the space defined by the enlarged diameter portion 13Ar in the horizontal hole 13Au and the enlarged diameter portion 14r in the large diameter portion 14g (the insertion hole) is adjacent to the rotary shaft 17 (the serration shaft portion 17e on the stepping motor 50 side). The large-diameter fitting portion 17d provided in the portion) is fitted (internally fitted so as to be slidable). The rotation shaft 17 is prevented from moving in the direction of the center line L by a step (stopper portion) formed by the enlarged diameter portion 13Ar in the horizontal hole 13Au and the enlarged diameter portion 14r in the large diameter portion 14g (the insertion hole). In this state, it rotates around the center line L.

  In the flow path switching valve 7 having such a configuration, when the rotor 57 of the stepping motor 50 is driven to rotate, the rotation of the rotor 57 is transmitted to the rotary shaft 17 by being decelerated via the output shaft 46 of the speed reduction mechanism 40. The valve shaft 20 is moved up and down in the direction of the axis O by the motion conversion mechanism 60 by the drive teeth 61 of the rotating shaft 17 and the driven teeth 62 of the thrust transmission shaft 27 meshing in the base member 13A. Also here, each valve body (the first valve body 21, the second valve body 22, and the third valve body 23) provided on the valve shaft 20 is in contact with the inner housing 9A in the valve chamber 7A. As the shaft 20 moves up and down, the communication state (flow direction, flow path) between the three inner ports p1, p2, p3 and the outer port p10 is switched as in the fifth embodiment. The upper back pressure chamber 30 defined on the upper side of the first valve body 21 and the first back pressure chamber 30 are connected via a communication passage 32 including a communication space 8A between 9A and the outer housing 9B (in other words, outside the inner housing 9A). Since the lower back pressure chamber 31 defined on the lower side of the three-valve body 23 is always in communication, the same effect as the fifth embodiment can be obtained.

  Further, in the present embodiment, the raising / lowering drive unit for raising and lowering the valve shaft 20 rotates the rotor 57 disposed rotatably around the rotation axis L extending in the direction perpendicular to the axis O direction and the rotor 57. A stepping motor 50 having a stator 55 for rotating, a rotary shaft 17 that is rotated integrally with the rotor 57, and a motion conversion mechanism 60 that converts the rotary motion of the rotary shaft 17 into a lifting motion of the valve shaft 20. As the motion converting mechanism 60, a drive tooth 61 as a pinion gear formed on the outer periphery of the rotating shaft 17 and a driven gear as a rack gear which is formed on the valve shaft 20 (thrust transmission shaft 27) and meshes with the drive tooth 61. Since the rack and pinion type constituted by the teeth 62 is adopted, for example, when switching from the heating operation to the defrosting operation and from the defrosting operation to the heating operation, the outer port p10 and the inner port are temporarily provided. The pressure difference between the high pressure side and the low pressure side can be reduced by communicating with the top p2, so that the noise can be effectively reduced and the stepping motor 50 constituting the lifting drive unit is mounted on the base of the valve body 10. It can be placed sideways (sideways) on the side of the member 13A, the overall length of the flow path switching valve 7 can be shortened, the overall configuration can be simplified, the time required for switching the communication state (flow path) can be shortened, etc. An effect is also obtained. Further, the configuration employing the rack and pinion type can greatly change the ascending / descending speed of the valve shaft 20 as compared with the configuration employing the above-described screw feed mechanism, so that the valve shaft 20 is changed when switching between the heating operation and the defrosting operation. By moving slowly, the pressure difference between the high pressure side and the low pressure side can be gradually reduced, and noise can be further reduced.

[Eighth Embodiment]
20-22 is a figure which shows 8th Embodiment of the flow-path switching valve based on this invention, FIG. 20 is a 1st flow state (valve shaft: descending position), FIG. 21 is a 2nd flow state. FIG. 22 shows the third flow state (valve shaft: intermediate position). In this example as well, the axis O of the valve body 10 and the center line (rotation axis) L of the stepping motor (lifting / lowering drive unit) 50 are set so as to be shifted due to the positional relationship of torsion. ), FIG. 21 (A), and FIG. 22 (A) are cross-sectional views taken along line Z-z1-z2-Z in FIG. 18 (C).

  The flow path switching valve 8 of the eighth embodiment is basically an arrangement of an inner port formed in the inner housing and a valve body formed in the valve shaft with respect to the flow path switching valve 7 in the seventh embodiment. The configuration is different in the configuration of the communication path 32 that always communicates the upper back pressure chamber 30 and the lower back pressure chamber 31 (see also the fourth embodiment shown in FIGS. 11 and 12). . Accordingly, components having the same functions as those of the seventh embodiment are denoted by the same reference numerals and detailed description thereof is omitted, and only the differences described above will be described in detail below.

  The flow path switching valve 8 of the present embodiment is used as a four-way switching valve in, for example, a heat pump type air conditioning system or the like, similar to the seventh embodiment, and is an upper side of the three inner ports p1, p2, and p3. The communication port p11 opened above the inner port p1 is formed so as to be positioned above the first valve body 21 when the valve shaft 20 is in the raised position (see FIG. 21). The communication port p12 opened below the port p3 is formed to be positioned below the second valve body 22 when the valve shaft 20 is in the lowered position (see FIG. 20). In addition, here, the three inner ports p1, p2, and p3 are opened apart (in the axis O direction (vertical direction)), and the upper inner port p1 and the lower inner port p3 are connected to the valve shaft 20. The two valve bodies (the first valve body 21 and the second valve body 22) provided in the opening are opened apart from each other (in the vertical direction), and the valve shaft 20 is in the intermediate position (the lowered position and the raised position). The outer port p10 formed in the outer housing 9B communicates with both the upper inner port p1 and the lower inner port p3 (via the communication space 8A and the like). (See FIG. 22).

  Further, in this example, the horizontal hole 32a in the cylindrical fitting portion 13Ab of the base member 13A and the horizontal hole 32b in the inner housing 9A (below the communication port p12) are omitted.

  On the other hand, the thrust transmission shaft 27 (the intermediate body portion 27b and the like) in the valve shaft 20 is formed long, and the connecting shaft 29 connected to the thrust transmission shaft 27 (the small diameter lower portion 27c) is relatively long. It is composed of a first connecting shaft constituting body 29A and a second connecting shaft constituting body 29B. A short cylindrical first valve body 21 and a second valve body 22 are integrally formed at the upper ends of the first connecting shaft constituting body 29A and the second connecting shaft constituting body 29B, respectively, and separated from each other in the axis O direction. Two short cylindrical valve bodies (first valve body 21 and second valve body 22) are arranged.

  Even in the flow path switching valve 8 having such a configuration, when the rotor 57 of the stepping motor 50 is rotationally driven, each valve body (the first valve body 21 and the second valve body 22) is in contact with the inner housing 9A. As the valve shaft 20 moves up and down in the valve chamber 7A, the communication state (flow direction, flow path) between the three inner ports p1, p2, p3 and the outer port p10 is switched.

  That is, when the rotor 57 of the stepping motor 50 is driven to rotate in one direction, the rotation of the rotor 57 is decelerated and transmitted to the rotary shaft 17 via the output shaft 46 of the speed reduction mechanism 40 and is rotated integrally with the rotor 57. The valve shaft 20 is lowered, for example, by the motion conversion mechanism 60 by the drive teeth 61 of the rotating shaft 17 and the driven teeth 62 of the thrust transmission shaft 27, and is in a lowered position (here, a second connecting shaft structure provided at the lower portion of the valve shaft 20). The position 29B is brought into contact with the stopper portion 11Bs of the inner peripheral member 11B of the lid member 11 and stopped. In this lowered position, the first valve body 21 is positioned between the inner port p1 and the inner port p2, and the second valve body 22 is positioned between the inner port p3 and the communication port p12. The space between 21 and the second valve body 22 is positioned directly beside the inner port p2 and the inner port p3. Thereby, the inner port p2 and the inner port p3 communicate with each other via the space between the first valve body 21 and the second valve body 22, and the inner port p1 and the outer port p10 are the first valve body in the valve chamber 7A. It communicates via the space above 21 (upper back pressure chamber 30), the communication port p11, and the communication space 8A (first flow state shown in FIG. 20).

  On the other hand, when the rotor 57 of the stepping motor 50 is driven to rotate in the other direction, the rotation of the rotor 57 is decelerated and transmitted to the rotary shaft 17 via the output shaft 46 of the speed reduction mechanism 40 and is rotated integrally with the rotor 57. For example, the valve shaft 20 is raised by the motion conversion mechanism 60 by the driving tooth 61 of the rotating shaft 17 and the driven tooth 62 of the thrust transmission shaft 27 to take the raised position. In this raised position, the first valve body 21 is positioned between the communication port p11 and the inner port p1, and the second valve body 22 is positioned between the inner port p2 and the inner port p3. The space between 21 and the 2nd valve body 22 is located just beside the inner side port p1 and the inner side port p2. Thus, the inner port p1 and the inner port p2 communicate with each other through the space between the first valve body 21 and the second valve body 22, and the inner port p3 and the outer port p10 are the second valve body in the valve chamber 7A. 22 communicates via a space (lower back pressure chamber 31), a communication port p12, and a communication space 8A (second flow state shown in FIG. 21).

  Moreover, in this embodiment, the intermediate position between the said fall position and a raise position is taken by making the valve shaft 20 stop in the middle. In this intermediate position, the first valve body 21 is positioned between the inner port p1 and the inner port p2, and the second valve body 22 is positioned between the inner port p2 and the inner port p3. The space between 21 and the 2nd valve body 22 is located just beside the inner side port p2. As a result, the inner port p1 and the outer port p10 communicate with each other via the space above the first valve body 21 (upper back pressure chamber 30), the communication port p11, the communication space 8A in the valve chamber 7A, and the inner port p3. And the outer port p10 communicate with each other via a space (lower back pressure chamber 31) below the second valve body 22 in the valve chamber 7A, a communication port p12, and a communication space 8A (third flow state shown in FIG. 22). ).

  Here, also in the present embodiment, the first valve body 21 is disposed above the first valve body 21 via the communication passage 32 including the communication space 8A between the inner housing 9A and the outer housing 9B (in other words, outside the inner housing 9A). Since the upper back pressure chamber 30 defined and the lower back pressure chamber 31 defined below the second valve body 22 are always in communication, the same effects as the seventh embodiment can be obtained. It is done.

  In each of the above embodiments, the lower end portion of the valve shaft 20 (for example, the second connecting shaft constituting body 29B in the eighth embodiment) is opposed to the stopper portion (for example, the stopper portion 11Bs in the eighth embodiment). Control is performed to stop the valve shaft 20 at a predetermined position (such as an ascending position or an intermediate position) by rotating the stepping motor 50 by a predetermined angle with respect to the position (downward position) stopped in contact.

  Moreover, in the said 1st-6th embodiment, although the electrically driven flow-path switching valve using the stepping motor which has a stator and a rotor as a raising / lowering drive part for raising / lowering a valve body is mainly employ | adopted. Of course, for example, an electromagnetic flow path switching valve using a solenoid or the like may be employed as the elevating drive unit.

1 flow path switching valve (first embodiment)
2 Channel switching valve (second embodiment)
3 Channel switching valve (Third embodiment)
4 Channel switching valve (fourth embodiment)
5 Channel switching valve (fifth embodiment)
6 Channel switching valve (sixth embodiment)
7 Channel switching valve (seventh embodiment)
8 Channel switching valve (8th embodiment)
7A Valve chamber 8A Communication space 9A Inner housing 9B Outer housing 10 Valve body 11 Lid-like member 17 Rotating lift shaft (first to sixth embodiments)
17 Rotating shaft (seventh and eighth embodiments)
20 valve shaft 21 first valve body 22 second valve body 23 third valve body 24 fourth valve bodies 21A to 24A seal members 21B to 24B packing 27 thrust transmission shaft 29 connecting shaft 30 upper back pressure chamber 31 lower back pressure chamber 32 Communication path 40 Strange planetary gear type reduction mechanism 50 Stepping motor 55 Stator 57 Rotor 58 Can 60 Motion conversion mechanism 61 Drive tooth 62 Driven teeth p1 to p5 Inner port p10 Outer port p10a Opening p11, p12 Communication ports # 1 to # 5, # 10 Conduit fitting

Claims (19)

A cylindrical inner housing having a valve chamber;
An outer housing disposed outside the inner housing to form a communication space outside the inner housing;
A valve shaft provided in the valve chamber so as to be movable up and down, and provided with at least two valve bodies inscribed in the inner housing separated in the axial direction;
An elevating drive unit for elevating the valve shaft in the axial direction in the valve chamber,
The elevating drive unit is rotated integrally with the rotor, and a stepping motor having a rotor disposed rotatably around a rotation axis extending in a direction perpendicular to the axial direction and a stator for rotating the rotor. And a motion conversion mechanism for converting the rotary motion of the rotary shaft into the vertical motion of the valve shaft,
In the inner housing, at least two inner ports that open to the valve chamber are opened apart in the axial direction, and at least one communication port that always communicates the valve chamber and the communication space is opened. ,
In the outer housing, an outer port that always communicates with the communication space is opened,
The upper back pressure chamber defined above the at least two valve bodies in the valve chamber and the lower back pressure chamber defined below the at least two valve bodies in the valve chamber are always in communication. And
The communication between the at least two inner ports and the outer ports is achieved by raising and lowering the valve shaft in the valve chamber by the raising and lowering drive unit in a state where the at least two valve bodies are inscribed in the inner housing. A flow path switching valve characterized in that the state can be switched.   The said motion conversion mechanism is comprised by the drive tooth formed in the outer periphery of the said rotating shaft, and the driven tooth which is formed in the said valve shaft and meshes with the said drive tooth. Flow path switching valve.   3. The flow path switching valve according to claim 1, wherein the rotation shaft is configured to rotate around the rotation axis while being prevented from moving in the direction of the rotation axis.   The flow path switching according to any one of claims 1 to 3, wherein the stepping motor is attached to a side of a base member attached to an end opening of the outer housing. valve.   The flow path switching valve according to claim 4, wherein a horizontal hole into which the rotating shaft is inserted and a vertical hole into which the valve shaft is inserted are provided inside the base member.   6. The flow according to claim 1, wherein the communication space is formed on an outer periphery of the inner housing, or is formed on a part of an outer periphery of the inner housing. Road switching valve.   The D-cut surface is provided on the outer periphery of the inner housing, and the communication space is formed by the D-cut surface and the inner peripheral surface of the outer housing. The flow path switching valve according to 1.   The flow path switching according to any one of claims 1 to 7, wherein the at least two inner ports and the outer port are opened to opposite sides or the same side as viewed in the axial direction. valve.   The communication port is located above the at least two inner ports and below the at least two inner ports, and has the same distance between the uppermost valve body and the lowermost valve body among the at least two valve bodies. The flow path switching valve according to any one of claims 1 to 8, wherein the flow path switching valve is opened at an interval.   When the valve shaft is in a predetermined position, the outer port communicates with both the uppermost inner port and the lowermost inner port of the at least two inner ports. The flow path switching valve according to any one of claims 1 to 8.   The outer port is opened in the communication space so as to always communicate with the communication space, or the communication through the opening opened at the same height as the communication port in the inner housing. The flow path switching valve according to any one of claims 1 to 10, wherein the flow path switching valve is always in communication with a space.   12. The upper back pressure chamber and the lower back pressure chamber are always in communication with each other via a communication path provided in the valve shaft. The flow path switching valve described.   The flow path switching valve according to any one of claims 1 to 11, wherein the upper back pressure chamber and the lower back pressure chamber are always in communication with each other through the communication space.   The seal member is mounted on the outer periphery of the at least two valve bodies, and the packing having higher hardness than the seal member is mounted on the outside of the seal member. The flow path switching valve according to Item.   The concave surface portion is provided in a portion where the at least two inner ports and the at least one communication port are formed on the inner periphery of the inner housing. Flow path switching valve.   The flow path switching valve according to claim 15, wherein a tapered surface portion is provided on an upper surface and / or a lower surface of the concave surface portion.   The flow path switching valve according to any one of claims 1 to 16, wherein the valve shaft includes a plurality of connecting shaft components each provided with one valve body. .   The flow path switching valve according to claim 1, wherein a lid-like member having a stopper portion that restricts the lowering of the valve shaft is attached to the outer housing or the inner housing.   The lid-like member is provided in the valve shaft so that the upper back pressure chamber and the lower back pressure chamber are always in communication when the valve shaft is brought into contact with the stopper and stopped. The flow path switching valve according to claim 18, wherein a vertical hole and a horizontal hole communicating with the communication path are provided.

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