JP2019199921A - Three-way switching valve - Google Patents

Abstract

To provide a three-way switching valve which can easily perform change and adjustment of a maximum flow rate at valve-opening time, and which also has excellent durability.SOLUTION: A driven member 60 which is moved up/down by a stepping motor 50 and which separates (raises) an upper part valve body 20 from an upper part valve seat 9a against an energization force of an upper part closing valve spring 20A, and a connection rod 65 for separating (pushing down) a lower part valve body 70 from a lower part valve seat 9b against an energization force of a lower part closing valve spring 70A are constituted as separate components from each other.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a three-way switching valve, and more particularly to a three-way switching valve used as a flow path switching device capable of switching the flow direction (flow path) of a fluid (refrigerant) and adjusting the flow rate in a refrigeration cycle such as an air conditioner. About.

  As this type of three-way switching valve, a valve body having an inflow / outlet, an inflow / outlet and an outflow / outlet, a first valve seat disposed between the inflow / outlet and the inflow port inside the valve body, and the valve body A second valve seat disposed between the inflow outlet and the outflow outlet in the interior of the valve body, and disposed on the same axis within the valve body, and capable of opening and closing the first valve seat and the second valve seat. A first valve body, a second valve body, a push-pull rod that is connected to the first valve body and the second valve body and pushes and pulls the first valve body and the second valve body, and drives the push-pull rod An electric actuator that opens the first valve body by pushing the first valve body through the push-pull rod, and the second valve body through the push-pull rod. To open the second valve body, and Both the first valve body and the second valve body are closed by moving the rod to an intermediate position that does not push the first valve body and does not pull the second valve body. Things are known.

  When the conventional three-way switching valve is provided in an air conditioner having a refrigeration cycle, the inlet / outlet is in an indoor unit, the inlet is in a high-pressure pipe of an outdoor unit, and the outlet is in a low-pressure pipe of an outdoor unit, By connecting both the first valve body and the second valve body simultaneously, the refrigerant circulation to the indoor unit that does not require air conditioning for cooling and heating can be blocked (for example, the following patents) Reference 1).

JP 2013-204695 A

  By the way, in the conventional three-way switching valve described in Patent Document 1, the first valve body is changed by changing the length of the push-pull rod that operates (pushes and pulls) the first valve body and the second valve body. It is conceivable to change and adjust the maximum flow rate when the valve is opened and the maximum flow rate when the second valve body is opened, but the push-pull rod is connected to the electric actuator as a male screw integrated structure. There is a problem that it is difficult to add processing to the push-pull rod.

  The push-pull rod contacts the first valve body and the second valve body while rotating to operate the first valve body and the second valve body, so that the push-pull rod, the first valve body and the second valve body are operated. The durability of the first valve seat and the second valve seat on which the first valve body and the second valve body are seated may be reduced.

  The present invention has been made in view of the above-mentioned problems, and the object thereof is three-way that can easily change and adjust the maximum flow rate at the time of valve opening and has excellent durability. It is to provide a switching valve.

  In order to solve the above-described problems, a three-way switching valve according to the present invention basically includes a valve chamber, a first inlet / outlet opening to the valve chamber, a second inlet / outlet, a third inlet / outlet, and the An upper valve seat provided between the first inlet / outlet and the second inlet / outlet; and a valve body having a lower valve seat provided between the first inlet / outlet and the third inlet / outlet; An upper valve body that is disposed in the valve chamber so as to be movable up and down, and that contacts and separates from the upper valve seat; a lower valve body that is disposed in the valve chamber so as to be movable up and down and contacts and separates from the lower valve seat; An upper urging member for urging the body in the valve closing direction, a lower urging member for urging the lower valve body in the valve closing direction, a relative movement in the ascending / descending direction with respect to the upper valve body, and A follower member disposed to be engageable with the upper valve body so as to separate the upper valve body from the upper valve seat against the urging force of the upper urging member. The driven member and the lower valve body can be moved integrally to separate the lower valve body from the lower valve seat against the urging force of the lower urging member, and the driven member and the lower valve A connecting member for connecting the body with each other so as to be relatively movable in the up-and-down direction, and a raising and lowering drive unit for raising and lowering the driven member, wherein the upper valve body is the upper valve according to the lift amount of the driven member The lower valve body is pushed down from the lower valve seat by the connecting member while being seated on the seat, the upper valve body is seated on the upper valve seat, and the lower valve body is seated on the lower valve seat. The seating state and the state where the upper valve body is pulled up from the upper valve seat by the driven member while the lower valve body is seated on the lower valve seat can be selectively taken. It is characterized by that.

  In a more specific preferred aspect, the upper valve body remains seated on the upper valve seat by the biasing force of the upper biasing member until the lift amount of the driven member reaches a predetermined first lift amount. The connecting member pushes down the lower valve body from the lower valve seat against the urging force of the lower urging member, and the lift amount of the driven member exceeds the first lift amount. Up to two lifts, the upper valve body is seated on the upper valve seat by the biasing force of the upper biasing member, and the lower valve body is seated on the lower valve seat by the biasing force of the lower biasing member. When the lift amount of the driven member exceeds the second lift amount, the lower valve body is seated on the lower valve seat by the urging force of the lower urging member, and the upper member is moved by the driven member. Energizing part The upper valve member is adapted to be lifted from the upper valve seat against the biasing force of the.

  In a preferred aspect, the connecting member is constituted by a cylindrical member or a columnar member extending along the ascending / descending direction.

  In another preferred aspect, the connecting member is inserted into the follower member so that the upper end portion thereof can be moved relative to the driven member and can be engaged with the driven member, and the lower end portion can be moved relative to the lower valve body and moved relative to the lower valve member. Interpolated as possible.

  In another preferred aspect, the upper biasing member is interposed between the upper valve body and the driven member.

  In another preferred embodiment, the upper urging member is interposed between the upper valve body and the valve body.

  In another preferred embodiment, the driven member is inserted into the upper valve body so as to be relatively movable in the up-and-down direction, and is engaged with the upper valve body on the outer periphery of the lower end portion of the driven member according to a lift amount. An outer hook-shaped locking portion for lifting the upper valve body from the upper valve seat is provided.

  In another preferred embodiment, a stopper mechanism that regulates the downward movement of the driven member includes the driven member and the upper valve body.

  In another preferred embodiment, a stopper mechanism that regulates the downward movement of the driven member includes the lower valve body and the valve body.

  In another preferred embodiment, the chamber diameter of the upper back pressure chamber defined above the upper valve body and the aperture of the upper valve seat are set to be the same, and the upper back pressure chamber and the valve chamber are always connected. An upper pressure equalizing passage is provided, and / or a chamber diameter of the lower back pressure chamber defined below the lower valve body and a diameter of the lower valve seat are set to be the same, and the lower A lower pressure equalizing passage that always communicates the back pressure chamber and the valve chamber is provided.

  In a further preferred aspect, the upper pressure equalizing passage includes a through hole provided in the connection member, a communication hole communicating the through hole and the valve chamber, and the inside of the driven member.

  In a further preferred aspect, the upper pressure equalizing passage is constituted by an upper vertical through passage provided inside the upper valve body.

  In a further preferred aspect, the lower pressure equalizing passage includes a through hole provided in the connecting member, a communication hole communicating the through hole and the valve chamber, and an inside of the lower valve body. .

  In a further preferred aspect, the lower pressure equalizing passage is configured by a lower vertical through passage provided inside the lower valve body.

  In another preferred aspect, the elevating drive unit includes a stepping motor having a stator that is externally mounted on a can fixed to the valve body, and a rotor that is rotatably disposed inside the can, and the rotor The driven member can be moved up and down without rotating via a screw feed mechanism provided between the driven member and the driven member.

  In a further preferred aspect, a planetary gear type speed reduction mechanism that reduces and transmits the rotation of the rotor is interposed between the rotor and the screw feed mechanism.

  According to the flow path switching valve of the present invention, the driven member for lifting and lowering the upper valve body from the upper valve seat against the biasing force of the upper biasing member that is lifted and lowered by the lift drive unit, The connecting member for separating (pressing down) the lower valve element from the lower valve seat against the urging force of the urging member is configured as a separate part. In addition, since it is sufficient to process the connecting member, for example, the maximum flow rate at the time of opening the valve can be easily changed and adjusted as compared with the conventional one using a push-pull rod with a male screw integrated structure. .

  Further, since the connecting member and the driven member can be moved up and down without rotating, the durability of the connecting member, the driven member, the lower valve body, the upper valve body, the lower valve seat, the upper valve seat, etc. is effectively enhanced. You can also.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a longitudinal sectional view showing a state of an upper valve body: closed and a lower valve body: opened (a position where a lift amount is 0) in a first embodiment of a three-way switching valve according to the present invention. The longitudinal cross-sectional view which shows the state (uplift amount is the position of 1st lift amount) of the upper valve body: closed and the lower valve body: closed of the three-way switching valve shown by FIG. The longitudinal cross-sectional view which shows the state (uplift amount is the position of 2nd lift amount) of the upper valve body: closed and the lower valve body: closed of the three-way selector valve shown by FIG. The longitudinal cross-sectional view which shows the state (open position of the maximum lift amount) of the upper valve body: open and the lower valve body: closed of the three-way switching valve shown by FIG. The figure which shows the relationship between the lift amount of a driven member, and the flow volume (opening area) of the three-way switching valve shown by FIG. The longitudinal cross-sectional view which shows the upper valve body: closed and the lower valve body: open state (position where lift amount is 0) of 2nd Embodiment of the three-way selector valve which concerns on this invention. The longitudinal cross-sectional view which shows the upper valve body: closed and the lower valve body: open state (position where lift amount is 0) of 3rd Embodiment of the three-way selector valve concerning this invention.

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

[First Embodiment]
1 to 4 are longitudinal sectional views showing a first embodiment of a three-way switching valve according to the present invention. FIG. 1 shows an upper valve body: closed and a lower valve body: opened (the lift amount is 0). 2), FIG. 2 shows the upper valve body: closed, the lower valve body: closed (the position where the lift amount is the first lift amount), and FIG. 3 shows the upper valve body: closed, the lower valve body: closed ( FIG. 4 shows a state where the upper valve body is open and the lower valve body is closed (position where the lift amount is maximum).

  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 three-way switching valve 1 of the illustrated embodiment is mainly composed of a valve body 5 having a tubular base 6 made of sheet metal, a can 58 fixed to the valve body 5, and an internal space defined by the valve body 5 and the can 58. The support member 19 fixedly disposed on the valve body 5, the upper valve body 20 and the lower valve body 70 disposed to be movable up and down in the internal space, and the follower member disposed to be engageable with the upper valve body 20. 60, a connecting rod (connecting member) 65 that connects the driven member 60 and the lower valve body 70, a stepping motor (elevating drive unit) 50 attached above the valve body 5 to raise and lower the driven member 60, It has.

  For example, a metal lid member 6A is hermetically attached to the lower opening of the tubular base body 6 of the valve body 5 by welding, caulking, brazing, or the like, and a valve chamber 7 is defined therein. The lateral inlet (second inlet / outlet) 11a and the outlet (third inlet / outlet) 12a that open to the valve chamber 7 are formed in the side portion so as to be spaced apart from each other in the direction of the axis O (the vertical direction). A lateral inlet / outlet (first inlet / outlet) 10a is formed between the outlet 12a and the outlet 12a. The conduit joints 10, 11, and 12 are attached to the inlet / outlet port 10a, the inlet port 11a, and the outlet port 12a by brazing or the like, respectively.

  In this example, the inlet / outlet port 10a, the inlet port 11a, and the outlet port 12a are formed on the opposite side (with an angular interval of 180 degrees) when viewed in a plan view (that is, in the direction of the axis O). However, it goes without saying that the positions of the inlet / outlet port 10a, the inlet port 11a, and the outlet port 12a in the circumferential direction can be changed as appropriate.

  A thick cylindrical valve seat member 8 having a communication port 8a communicating with the inlet / outlet 10a is welded to the inner periphery between the inlet 11a and the outlet 12a in the cylindrical base 6 of the valve body 5. It is fixed by insertion, caulking, brazing, etc.

  The valve seat member 8 is made of, for example, a metal material such as SUS. The upper end side opening is an upper valve seat 9a, the lower end side opening is a lower valve seat 9b, and the communication port is formed in the middle of the abdomen. 8a is formed. The upper and lower end portions of the valve seat member 8 are formed with an upper tapered surface 9c and a lower tapered surface 9d connected to the upper valve seat 9a and the lower valve seat 9b. Here, the diameter φa of the upper valve seat 9a and the lower valve seat 9b (that is, the inner diameter of the cylindrical valve seat member 8) is the chamber diameter φb of the upper back pressure chamber 30 defined above the upper valve body 20. And the chamber diameter φc of the lower back pressure chamber 80 defined below the lower valve body 70 is set to be substantially the same (detailed later).

  A stepped tubular base 13 is attached to the upper opening of the tubular base body 6 of the valve body 5, and the ceiling surface of the valve chamber 7 is formed by the lower surface of the tubular base 13. The lower end of a cylindrical can 58 with a ceiling is joined to the outer periphery of 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 partition wall 14c and a bearing member 15 with a female screw 15i. The cylindrical holding member 14 is a portion below the partition wall 14c on the inner side of the cylindrical base 13. A cylindrical and downwardly opened sleeve portion 14d is fixed by press-fitting or the like so as to protrude into the valve chamber 7. And the cylindrical bearing member 15 by which the internal thread 15i was screwed by the inner peripheral lower half part is being fixed to the upper part of the cylindrical holding member 14 by caulking. Further, a spring chamber 14a is defined between the partition wall 14c of the cylindrical holding member 14 and the bearing member 15, and a compression coil spring 25 that biases the driven member 60 upward is accommodated in the spring chamber 14a. . A portion of the inner periphery of the bearing member 15 above the female screw 15i is a fitting hole 15a into which a lower portion of an output shaft 46 of a speed reduction mechanism 40 described later is fitted.

  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 whose upper portion is fixed by press-fitting into a hole formed at the bottom of the output gear 45. 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 in the central portion of the upper portion of the output shaft 46, and the lower portion of the support shaft 49 that is inserted through the central portion 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 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 lower portion of the output shaft 46 is laterally passed through its center. A slit-like fitting portion 46a extending in the direction 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 a female screw 15i screwed on the inner periphery of the bearing member 15 is provided, and the plate-like portion 17c is fitted in a slit shape. The joint 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 lift shaft 17, and is rotated by a screw feed mechanism including the female screw 15 i of the bearing member 15 and the male screw 17 a of the rotary lift shaft 17. The elevating shaft 17 moves up and down while rotating.

  Below the rotary lift shaft 17, a stepped cylindrical thrust transmission shaft 23 and a substantially cylindrical follower member 60 through which thrust downward of the rotary lift shaft 17 is transmitted via the ball 18, the ball seat 16. Are integrally disposed along the axis O (in the up-and-down direction). In addition, by interposing the ball 18 between the rotary lift shaft 17 and the thrust transmission shaft 23, for example, even if the rotary lift shaft 17 is lowered while rotating, the thrust transmission shaft 23 (and the driven member) is rotated from the rotary lift shaft 17. Only the downward thrust is transmitted to 60), and the rotational force is not transmitted.

  Here, as described above, the compression coil spring 25 housed in the spring chamber 14a above the partition wall 14c of the cylindrical holding member 14 is disposed with its lower end in contact with the partition wall 14c. In order to transmit the urging force (pull-up force) of the compression coil spring 25 to the thrust transmission shaft 23 (and the driven member 60), a pull-up spring receiving body 28 having a hook-like hook portion on the top and bottom is arranged. The upper hook portion of the lifting spring receiver 28 is placed on the upper portion of the compression coil spring 25, and the lower hook portion is hooked on the thrust transmission shaft 23 (the lower end step surface of the large-diameter upper portion 23a). The cylindrical holding member 14 is formed with a communication hole 14e that allows the spring chamber 14a and the can 58 to communicate with each other.

  The thrust transmission shaft 23 includes, from above, a large-diameter upper portion 23a into which the ball seat 16 is fitted on the inner periphery, an intermediate body portion 23b inserted through a central hole formed in the partition wall 14c of the cylindrical holding member 14, and an intermediate body The lower portion 23c is smaller in diameter than the portion 23b, and opens into a vertical hole 23d composed of a vertical through hole constituting the upper portion of the upper pressure equalizing passage 31 described later and an upper back pressure chamber 30 described later. A plurality of lateral holes 23e are formed. Note that the upper end opening of the vertical hole 23 d is closed by the ball seat 16.

  The center hole 61 of the driven member 60 disposed below the thrust transmission shaft 23 is formed with a step, and the small diameter lower portion 23 c of the thrust transmission portion shaft 23 is an upper large diameter fitting hole of the center hole 61 of the driven member 60. The driven member 60 and the thrust transmission shaft 23 are lifted and lowered integrally with the 61a by press fitting or the like. When the small diameter lower portion 23c is press-fitted between the upper end surface of the driven member 60 and the lower end step portion of the intermediate body portion 23b of the thrust transmission shaft 23, the spring receiver and the follower of the upper valve closing spring 20A (the upper end thereof) described later are driven. A saddle-shaped member 62 made of a thick disc that also functions as one of stoppers that regulates the downward movement of the member 60 (in other words, defines the lowering limit position of the driven member 60) is sandwiched and fixed.

  Further, on the outer periphery of the lower end portion of the driven member 60, the upper valve body 20 is engaged with the upper valve body 20 (the lower surface thereof) slidably inserted on the driven member 60 to prevent the upper valve body 20 from coming off and locked (that is, And an outer hook-like locking portion 63 for projecting the upper valve body 20 (projecting outward).

  Further, an upper end portion of a cylindrical connecting rod 65 described later is fitted (from the lower side) into the lower large-diameter insertion hole 61b of the center hole 61 of the driven member 60 so as to be slidable (in other words, relatively movable). ), And the upper end portion (surface) of the connecting rod 65 is in contact with the upper end step portion of the lower large-diameter fitting insertion hole 61b.

  The upper valve body 20 is formed in a stepped cylindrical shape, and can slide on the sleeve portion 14d in the axis O direction (up and down direction) so that the lower portion protrudes from the sleeve portion 14d of the cylindrical holding member 14. The driven member 60 is fitted into the inner side (from the lower side) so as to be slidable in the direction of the axis O (in the up-and-down direction) (that is, relatively movable) and the outer hook-shaped locking part 63. Is retained and inserted by the stopper. In other words, the upper valve body 20 is slidably inserted between the flange-shaped member 62 and the outer flange-shaped engaging portion 63 of the driven member 60 so as to be slidable in the direction of the axis O (the vertical direction). A pressing member 21 is fixed to the stepped portion provided on the outer periphery of the upper valve body 20 by caulking or the like, and is formed by the pressing member 21 and a stepped portion formed on the upper outer periphery of the upper valve body 20. An O-ring for sealing the gap between the upper valve body 20 (the outer peripheral surface thereof) and the sleeve portion 14d (the inner peripheral surface thereof) in the annular groove (made of Teflon (registered trademark)). A seal member 22 made of a cap seal or the like is attached.

  Further, the upper valve body 20 faces downward (valve closing direction) between an inner circumferential stepped portion (step surface) 20a formed on the inner periphery of the upper surface of the upper valve body 20 and the bowl-shaped member 62 (the lower surface thereof). An upper valve closing spring 20A composed of a compression coil spring as an upper urging member to be urged is interposed (reduced), and at the center of the upper surface of the upper valve body 20 (around the upper valve closing spring 20A). The cylindrical stopper convex portion 20b that constitutes the other of the stopper function for regulating the downward movement of the driven member 60 together with the flange-shaped member 62 (specifically, in contact with the flange-shaped member 62) protrudes (upward). It is installed.

  Here, the lower end outer peripheral portion of the upper valve body 20 is an upper valve body portion that is seated (from the upper side) on the upper valve seat 9 a of the valve seat member 8.

  On the other hand, in this example, the lower valve body 70 is formed to have an outer shape that is substantially the same diameter as the upper valve body 20 and is approximately inverted from the upper valve body 20. The lid-like member 6A of the valve main body 5 is provided with a cylindrical and upwardly opening sleeve portion 6d protruding upward (toward the valve chamber 7 side). The sleeve 6d is inserted into the sleeve 6d so as to be slidable in the direction of the axis O (the up-and-down direction) so as to protrude from the sleeve 6d of 6A. The lower valve body 70 is provided with a stepped central hole 70a along the direction of the axis O (the up-and-down direction), and the upper large-diameter fitting insertion hole 70b of the central hole 70a has a cylindrical shape described later. The lower end portion of the connecting rod 65 is fitted (from the upper side) so as to be slidable (in other words, relatively movable), and at the lower end step portion of the upper large-diameter fitting insertion hole 70b, the lower end of the connecting rod 65 is inserted. The part (surface) comes into contact. A pressing member 71 is fixed by caulking or the like to the stepped portion provided on the outer periphery of the lower end of the lower valve body 70, and is formed by the pressing member 71 and the stepped portion formed on the lower outer periphery of the lower valve body 70. An O-ring for sealing the annular groove between the lower valve body 70 (the outer peripheral surface thereof) and the sleeve portion 6d (the inner peripheral surface thereof) (sliding surface gap formed thereon), manufactured by Teflon (registered trademark) A seal member 72 made of a cap seal or the like is attached.

  Further, a lower portion that urges the lower valve body 70 upward (in the valve closing direction) between the pressing member 71 (the lower surface thereof) fixed to the lower valve body 70 and the lid-like member 6A (the outer peripheral portion of the upper surface thereof). A lower valve closing spring 70A composed of a compression coil spring as an urging member is interposed (reduced).

  Here, the upper end outer peripheral portion of the lower valve body 70 is a lower valve body portion that is seated (from the lower side) on the lower valve seat 9 b of the valve seat member 8.

  A connecting rod 65 made of a cylindrical member is inserted between the driven member 60 and the lower valve body 70 so as to pass through the inside of the valve seat member 8 along the axis O direction (up and down direction). Is distributed. As described above, the upper end portion of the connecting rod 65 is slidably fitted into the lower large-diameter fitting insertion hole 61b of the center hole 61 of the driven member 60, and the lower end portion thereof is the central hole 70a of the lower valve body 70. The driven member 60 and the lower valve body 70 can be moved relative to each other in the direction of the axis O (the up-and-down direction) via the connecting rod 65. Yes. The upper end portion of the connecting rod 65 abuts and engages with the driven member 60 (the upper stepped portion of the lower large-diameter fitting hole 61b), and the lower end portion of the connecting rod 65 is the upper portion of the lower valve body 70 (the upper portion thereof). The driven member 60 and the lower valve body 70 can be integrally moved via the connecting rod 65. The lower end step portion of the large-diameter insertion hole 70b is in contact with and engaged therewith. (Details later).

  In addition, a plurality of (or one) may be provided in the central portion (in the direction of the axis O) of the connecting rod 65 to communicate the longitudinal through hole 66 provided in the connecting rod 65 and the valve chamber 7. A communication hole 67 made of a horizontal hole is established.

  In this example, the upper end portion of the connecting rod 65 is slidably fitted into the lower large-diameter fitting insertion hole 61 b of the center hole 61 of the driven member 60, and the lower end portion is the center hole of the lower valve body 70. 70a is slidably fitted in the upper large-diameter insertion hole 70b, but the driven member 60 and the lower valve body 70 can be moved relative to each other in the direction of the axis O (elevating direction) via the connecting rod 65. In addition, it is only necessary to be able to move integrally through the connecting rod 65. For example, only the connecting rod 65 (the upper end portion thereof) may be fixed to the driven member 60 (the center hole 61 thereof). It goes without saying that only the connecting rod 65 (the lower end portion thereof) may be fixed to the lower valve body 70 (the central hole 70a thereof).

  The thrust transmission shaft 23 is defined above the upper valve body 20 by the horizontal hole 23e and the vertical hole 23d, the center hole 61 of the driven member 60, the upper half of the through hole 66 of the connecting rod 65 and the communication hole 67. The upper back pressure chamber 30 (specifically, the space surrounded by the upper valve body 20, the sleeve portion 14 d, and the partition wall 14 c) and the upper pressure equalizing passage 31 that communicates with the valve chamber 7 is configured. The lower back pressure chamber 80 defined on the lower side of the lower valve body 70 by the central hole 70a of the lower valve body 70, the lower half of the through hole 66 of the connecting rod 65 and the communication hole 67 (in detail, A lower pressure equalizing passage 81 communicating with the valve chamber 7 and a space surrounded by the lower valve body 70, the sleeve portion 6d, and the lid-like member 6A is formed. Further, in order to balance the push-down force and push-up force acting on the upper valve body 20 in the closed state (cancel the differential pressure), the chamber diameter φb of the upper back pressure chamber 30 (that is, the inner diameter of the sleeve portion 14d) is: The upper valve seat 9a has a diameter φa (that is, the inner diameter of the cylindrical valve seat member 8) that is set to be substantially the same, and balances the pressure-up force and the pressure-down force acting on the lower valve body 70 in the closed state (differential pressure). The chamber diameter φc of the lower back pressure chamber 80 (that is, the inner diameter of the sleeve portion 6d) is substantially the same as the diameter φa of the lower valve seat 9b (that is, the inner diameter of the cylindrical valve seat member 8). Is set to

  In the three-way switching valve 1 having such a configuration, when the rotor 57 of the stepping motor 50 is rotationally driven, the rotary elevating shaft 17 moves up and down while rotating, but between the rotary elevating shaft 17 and the thrust transmission shaft 23 and the driven member 60. By interposing the ball 18, only the downward thrust is transmitted from the rotary lift shaft 17 to the thrust transmission shaft 23 and the driven member 60 (rotational force is not transmitted), and the rotary lift shaft 17, the thrust transmission shaft 23 and the driven shaft are transmitted. The member 60 is integrally moved up and down in the direction of the axis O. As a result, the upper valve body 20 sheathed on the driven member 60 and the lower valve body 70 connected to the driven member 60 via the connecting rod 65 are brought into contact with and separated from the upper valve seat 9a and the lower valve seat 9b of the valve seat member 8. Thus, the flow direction (flow path) among the inlet / outlet 10a, the inlet 11a, and the outlet 12a is switched.

  More specifically, in the three-way switching valve 1 of the present embodiment, the lift amount (valve opening degree) of the driven member 60 (and the upper valve body 20 and the lower valve body 70) as shown in FIG. In the state (in other words, when it is at the lowest position), the hook-like member 62 of the driven member 60 contacts the stopper convex portion 20b of the upper valve body 20, and the upper valve body 20 (the upper valve body portion) is the upper valve. Seated on the seat 9a (specifically, pressed by the urging force of the upper valve closing spring 20A), the upper end opening of the valve seat member 8 is closed, and the upper end step portion of the lower large-diameter fitting hole 61b of the upper valve body 20 is closed. Comes into contact with the upper end portion of the connecting rod 65, and the lower end portion of the connecting rod 65 comes into contact with the lower end step portion of the upper large-diameter fitting insertion hole 70b of the lower valve body 70 to resist the biasing force of the lower valve closing spring 70A. The lower valve body 70 (the lower valve body portion) is separated from the lower valve seat 9b and the valve seat member 8 The lower end opening is opened, and the fluid (refrigerant) flows from the conduit joint 10 connected to the inlet / outlet 10a to the communication port 8a of the valve seat member 8 → the inside of the valve seat member 8 → the lower end opening of the valve seat member 8 (lower valve). It flows to the conduit joint 12 connected to the outlet 12a via the seat 9b). When the lift amount of the driven member 60 is 0, the flow rate of the fluid (refrigerant) flowing into the outflow port 12a is maximum (see FIG. 5). At this time, the lower valve body 70 (the lower valve body portion) and the lower valve seat 9b are positioned away from each other by the first lift amount L1 in the direction of the axis O (in the up-and-down direction). The portion 63 (the upper surface thereof) and the upper valve body 20 (the lower surface thereof) are positioned apart from each other by the second lift amount L2 in the direction of the axis O (the up-and-down direction), and the second lift amount L2 is greater than the first lift amount L1. The dimension shape of each part is set so that it may become large.

  When the rotor 57 of the stepping motor 50 is rotationally driven in one direction from the state shown in FIG. 1, 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. The rotary elevating shaft 17 is raised while being rotated by screw feeding by the female screw 15 i of the member 15 and the male screw 17 a of the rotary elevating shaft 17, and accordingly, the driven member 60 is pulled up together with the rotary elevating shaft 17. When the driven member 60 is raised, as shown in FIG. 2, the upper valve body 20 (the upper valve body portion thereof) is moved to the upper valve seat by the urging force of the upper valve closing spring 20A up to the first lift amount L1. The driven member 60 is moved so as to slide in the upper valve body 20 while sitting on 9a and the upper end opening of the valve seat member 8 is closed. At this time, since the length of the upper valve closing spring 20A (in the direction of the axis O) gradually increases, the sealing performance (pressing force) of the upper valve body 20 against the upper valve seat 9a gradually decreases. At the same time, the lower valve body 70 connected to the driven member 60 via the connecting rod 65 is raised (together with the driven member 60) by the urging force of the lower valve closing spring 70A, and flows into the outlet 12a (refrigerant). ) Gradually decreases (see FIG. 5), and when the lift amount of the driven member 60 reaches the first lift amount L1, the lower valve body 70 (the lower valve body portion thereof) is moved to the lower valve seat 9b (lower side). From the bottom, the lower end opening of the valve seat member 8 is closed (specifically, pressed by the urging force of the lower valve closing spring 70A). At this time, the outer flange-like locking portion 63 (the upper surface) of the driven member 60 and the upper valve body 20 (the lower surface) are positioned apart by L2-L1 in the axis O direction (up and down direction).

  When the driven member 60 is further raised to the first lift amount L1, and then the driven member 60 is further raised, as shown in FIG. 3, the upper valve closing spring 20A is attached until the second lift amount L2. The upper valve body 20 (the upper valve body portion thereof) is seated on the upper valve seat 9a by the urging force, the upper end opening of the valve seat member 8 is closed, and the lower valve body 70 is urged by the urging force of the lower valve closing spring 70A. (The lower valve body portion) is seated on the lower valve seat 9b and the lower end opening of the valve seat member 8 is closed, and the driven member 60 is located on the inner side of the upper valve body 20 and the outer side of the connecting rod 65 (the upper end portion thereof). When the lift amount of the driven member 60 reaches the second lift amount L2, the outer hook-like locking portion 63 of the driven member 60 is engaged with the upper valve body 20. At this time, the length of the upper valve closing spring 20A (in the direction of the axis O) gradually increases.

  When the driven member 60 is raised to the second lift amount L2 and then the driven member 60 is further raised, as shown in FIG. 4, the outer hook-like locking portion 63 of the driven member 60 becomes the upper valve body 20. The lower valve body 70 (the lower valve body portion) is seated on the lower valve seat 9b by the urging force of the lower valve closing spring 70A, and the lower end opening of the valve seat member 8 is closed, and the upper valve body is closed. 20 is moved (increased) together with the driven member 60, the upper valve body 20 (the upper valve body portion thereof) is separated from the upper valve seat 9a, the upper end opening of the valve seat member 8 is opened, and the fluid ( Refrigerant) enters from the conduit joint 11 connected to the inflow port 11a through the upper end opening (upper valve seat 9a) of the valve seat member 8 → the inside of the valve seat member 8 → the communication port 8a of the valve seat member 8. It flows to the conduit joint 10 connected to the outlet 10a. As the driven member 60 rises, the upper valve body 20 (the lower valve body portion thereof) is further separated from the upper valve seat 9a, and the flow rate of the fluid (refrigerant) flowing into the inlet / outlet port 10a gradually increases. When the lift amount reaches the maximum lift amount Lmax (that is, when the upper valve body 20 (the upper valve body portion thereof) is positioned apart from the upper valve seat 9a by Lmax-L2 in the axis O direction (lifting direction)). The flow rate of the fluid (refrigerant) flowing into the inlet / outlet 10a is also maximized (see FIG. 5). At this time, the length (in the direction of the axis O) of the upper valve closing spring 20A is constant and does not change.

  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. The rotary elevating shaft 17 is lowered while being rotated by the screw feed, and the driven member 60 is pushed down together with the rotary elevating shaft 17 against the urging force of the compression coil spring 25 by the thrust of the rotary elevating shaft 17. When the driven member 60 is lowered, the lower valve body 70 (the lower valve body portion thereof) is seated on the lower valve seat 9b by the urging force of the lower valve closing spring 70A. The upper valve body 20 (the upper valve body portion thereof) is seated (from the upper side) on the upper valve seat 9a while the lower end opening of the valve seat member 8 is closed, and then the upper end opening of the valve seat member 8 is closed. When further lowered, the upper valve body 20 (the upper valve body portion thereof) is seated on the upper valve seat 9a by the urging force of the upper valve closing spring 20A, and the upper end opening of the valve seat member 8 is kept closed, and the lower valve is closed. The lower valve body 70 (the lower valve body portion thereof) is separated from the lower valve seat 9b against the biasing force of the valve spring 70A, and the lower end opening of the valve seat member 8 is opened. When the follower member 60 is further lowered after the upper valve body 20 (the upper valve body portion) is seated on the upper valve seat 9a (from the upper side) and the upper end opening of the valve seat member 8 is closed, the follower is moved. Since the length (in the direction of the axis O) of the upper valve closing spring 20A interposed between the flange-shaped member 62 of the member 60 and the upper valve body 20 is gradually shortened (that is, compressed), the upper valve body 20 The sealing performance (pressing force) against the upper valve seat 9a gradually increases.

  Here, in this embodiment, when the upper valve body 20 (the upper valve body portion thereof) is seated on the upper valve seat 9a (the state shown in FIGS. 1 to 3), from the through hole 66 of the connecting rod 65 and the like. The upper back pressure chamber 30 defined on the upper side of the upper valve body 20 and the valve chamber 7 are always in communication with each other through the upper pressure equalizing passage 31. In other words, the upward surface of the upper valve body 20 (surface on the upper back pressure chamber 30 side) and the downward surface of the upper valve body 20 (surface on the valve chamber 7 side) are equalized. The chamber diameter φb of the upper back pressure chamber 30 (that is, the inner diameter of the sleeve portion 14d) and the diameter φa of the upper valve seat 9a (that is, the inner diameter of the cylindrical valve seat member 8) are set to be substantially the same. Yes.

  Therefore, the balance of the forces acting on the moving direction of the upper valve body 20 (the push-down force and the pushing-up force acting on the upper valve body 20) when the flow path is switched by the movement of the upper valve body 20 in the axis O direction (all the differential pressures). Canceling), the load acting on the upper valve body 20 when the flow path is switched can be made as small as possible, and the driving torque by the stepping motor 50 can be reduced.

  Similarly, when the lower valve body 70 (the lower valve body portion) is seated on the lower valve seat 9b (the state shown in FIGS. 2 to 4), the lower pressure equalizing passage including the through hole 66 of the connecting rod 65 and the like. The lower back pressure chamber 80 and the valve chamber 7 defined on the lower side of the lower valve body 70 are always in communication with each other through the valve 81. In other words, the downward surface of the lower valve body 70 (surface on the lower back pressure chamber 80 side) and the upward surface of the lower valve body 70 (surface on the valve chamber 7 side) are equalized. The chamber diameter φc of the lower back pressure chamber 80 (that is, the inner diameter of the sleeve portion 6d) and the diameter φa of the lower valve seat 9b (that is, the inner diameter of the cylindrical valve seat member 8) are set to be substantially the same. Yes.

  Therefore, the balance of the force (the pushing force and the pushing force acting on the lower valve body 70) acting in the moving direction of the lower valve body 70 when the flow path is switched by the movement of the lower valve body 70 in the direction of the axis O (all the differential pressures). Canceling), the load acting on the lower valve body 70 when the flow path is switched can be made as small as possible, and the driving torque by the stepping motor 50 can be reduced.

  Further, in the three-way switching valve 1 of the present embodiment, the follower is moved up and down by the stepping motor 50 to separate (pull up) the upper valve body 20 from the upper valve seat 9a against the urging force of the upper valve closing spring 20A. The member 60 and the connecting rod 65 for separating (pressing down) the lower valve body 70 from the lower valve seat 9b against the urging force of the lower valve closing spring 70A are configured as separate parts. When changing or adjusting the maximum flow rate, for example, it is only necessary to process the connecting rod 65 or the like (see FIG. 5). For example, compared to the conventional one using a push-pull rod with a male screw integrated structure, the valve is opened. The maximum flow rate can be changed and adjusted easily.

  In addition to the connecting rod 65 or instead of the connecting rod 65, the shape and dimensions of the driven member 60, the upper valve body 20, and the lower valve body 70 are changed to change the maximum flow rate when the valve is opened. Adjustments may be made.

  Further, since the connecting rod 65 and the driven member 60 can be moved up and down without rotating, the connecting rod 65 and the driven member 60, the lower valve body 70, the upper valve body 20, the lower valve seat 9b, the upper valve seat 9a, etc. Durability can also be effectively increased.

  Further, in the three-way switching valve 1 of the present embodiment, as described above, the upper valve closing spring 20 </ b> A is interposed between the flange-shaped member 62 of the driven member 60 and the upper valve body 20 that are moved up and down with respect to the valve body 5. Since it is interposed, the sealing performance (pressing force) of the upper valve body 20 with respect to the upper valve seat 9a can be effectively enhanced.

[Second Embodiment]
FIG. 6 shows a second embodiment of the three-way switching valve according to the present invention.

  The three-way switching valve 2 of the second embodiment is mainly composed of an upper valve closing spring 20A for energizing the upper valve body 20 in the valve closing direction with respect to the three-way switching valve 1 of the first embodiment, and a driven member 60 ( That is, the arrangement configuration of the stopper mechanism for regulating the downward movement of the lower valve body 70) is different, and the other configurations are substantially the same. Accordingly, portions corresponding to the respective portions of the first embodiment are denoted by common reference numerals, and redundant description is omitted, and hereinafter, differences will be mainly described.

  In the three-way switching valve 2 of the second embodiment, the hook-shaped member 62 serving as one of the spring receiver of the upper valve closing spring 21 (the upper end thereof) and the stopper function for restricting the downward movement of the driven member 60 is omitted. The upper valve body 20 faces downward (closed) between the pressing member 21 (the upper surface thereof) fixed to the outer periphery of the upper end of the body 20 and the cylindrical holding member 14 (the outer peripheral portion of the partition wall 14c) fixed to the valve body 5. An upper valve closing spring 20A composed of a compression coil spring as an upper biasing member biasing in the valve direction) is interposed (reduced).

  Further, a slightly movable small cylindrical movable stopper convex portion 70c constituting one of the stopper functions for restricting the downward movement of the driven member 60 is projected (downward) at the center of the lower surface of the lower valve body 70, and the valve body A slightly large-diameter columnar fixed stopper convex portion 6c that constitutes the other of the stopper functions protrudes (upward) at the center of the upper surface of the lid-shaped member 6A of No. 5, and together with the driven member 60 according to the lift amount. When the lower valve body 70 is lowered, the movable stopper convex portion 70c comes into contact with the fixed stopper convex portion 6c, and the lift amount (valve opening degree) of the driven member 60 (and the upper valve body 20 and the lower valve body 70) is increased. The state of 0 (in other words, the lowest position) can be taken.

  In the present embodiment, the lower surface central portion (the movable stopper convex portion 70c) of the lower valve body 70 abuts on the upper surface central portion (the fixed stopper convex portion 6c) of the lid-like member 6A of the valve body 5. The movable stopper convex portion 70c of the valve body 70 is provided with a plurality (or one) of horizontal holes 70d that allow the central hole 70a and the lower back pressure chamber 80 to communicate with each other. A lower pressure equalizing passage 81 that connects the lower back pressure chamber 80 and the valve chamber 7 is constituted by the hole 70 a, the lower half portion of the through hole 66 of the connecting rod 65, and the communication hole 67.

  Further, in the present embodiment, in addition to the above configuration, in order to suppress the generation of abnormal noise when the fluid (refrigerant) passes, the communication hole 67 that connects the through hole 66 of the connecting rod 65 and the valve chamber 7 includes the above-described configuration. Instead of the central part (in the direction of the axis O) of the connecting rod 65 as in the first embodiment (that is, the position facing the inlet / outlet 10a), the upper and lower parts (in the direction of the axis O) of the connecting rod 65, more specifically, It is provided in the recessed hole 20B provided in the lower surface of the upper valve body 20, and the part located in the recessed hole 70B provided in the upper surface of the lower valve body 70.

  In the three-way switching valve 2 of the second embodiment configured as described above, unlike the three-way switching valve 1 of the first embodiment, the upper valve closing spring 20 </ b> A is a presser fixed to the outer periphery of the upper end of the upper valve body 20. Since it is interposed between the member 21 and the cylindrical holding member 14 fixed to the valve body 5, when the driven member 60 is raised by rotating the rotor 57 of the stepping motor 50 in one direction, Up to the second lift amount L2 (see FIG. 3) beyond the first lift amount L1 (see FIG. 2), the upper valve body 20 (the upper valve body portion thereof) is seated on the upper valve seat 9a and the valve seat member 8 While the upper end opening of the upper valve body 20 is closed, the length (in the direction of the axis O) of the upper valve closing spring 20A is constant and does not change (that is, the sealing performance (pressing force) of the upper valve body 20 with respect to the upper valve seat 9a does not change). When the second lift amount L2 is exceeded, the driven member 60 The upper valve body 20 (the upper valve body portion thereof) is separated from the upper valve seat 9a by the shaped locking portion 63, the upper end opening of the valve seat member 8 is opened, and the length of the upper valve closing spring 20A (in the direction of the axis O) is It gradually becomes shorter (that is, compressed).

  Also in the three-way switching valve 2 of the second embodiment configured as described above, since the driven member 60 and the connecting rod 65 are configured as separate parts, the same functions and effects as those of the three-way switching valve 1 of the first embodiment are used. Is obtained, and the configuration around the upper valve body 20 can be simplified.

[Third Embodiment]
FIG. 7 shows a third embodiment of the three-way switching valve according to the present invention.

  The three-way selector valve 3 of the third embodiment is mainly different from the three-way selector valve 2 of the second embodiment in the arrangement configuration of the upper pressure equalizing passage 31 and the lower pressure equalizing passage 81. The configuration is substantially the same. Accordingly, portions corresponding to the respective portions of the second embodiment are denoted by common reference numerals and redundant description is omitted, and hereinafter, differences will be mainly described.

  In the three-way switching valve 3 of the third embodiment, the lateral hole 23e of the thrust transmission shaft 23, the center hole 61 of the driven member 60 (the lower large-diameter fitting hole 61b into which the upper end of the connecting rod 65 is inserted so as to be relatively movable). And the horizontal hole 70d and the central hole 70a of the lower valve body 70 (parts other than the upper large-diameter fitting hole 70b into which the lower end of the connecting rod 65 is inserted so as to be relatively movable) are omitted. The connecting rod 65 is composed of a cylindrical member (in other words, a solid member) that is long in the direction of the axis O (in the up-and-down direction) instead of a cylindrical member (in other words, a hollow member).

  Further, in order to communicate the upper back pressure chamber 30 and the valve chamber 7, a plurality of (or one) upper vertical through passages 20 e penetrating the upper valve body 20 in the vertical direction may be opened, and the lower back pressure chamber may be provided. A plurality of (or even one) lower vertical through passages 70 e that penetrate the lower valve body 70 in the vertical direction are provided in order to communicate the valve chamber 7 with the valve chamber 7, and are provided inside the upper valve body 20. The upper vertical equalizing passage 31 is constituted by the upper vertical through passage 20e, and the lower equalizing passage 81 is constituted by the lower vertical through passage 70e provided in the lower valve body 70.

  Also in the three-way switching valve 3 of the third embodiment configured as described above, the driven member 60 and the connecting rod 65 are configured as separate parts, so the three-way switching valves 1 and 2 of the first and second embodiments described above. In addition to obtaining the same operational effects, the configuration of the driven member 60 and the connecting rod 65 can be simplified and reduced in size (for example, reduced in diameter). Although the rod-shaped member having a circular cross section is used for the connecting rod 65 of the present embodiment, a plate-shaped member having a rectangular cross section or an ellipse may be used. In this case, the pressure loss when the refrigerant passes through the valve chamber 7 can be reduced.

  In the above embodiment, the inlet / outlet (first inlet / outlet) 10a is connected to the indoor unit of the air conditioner having a refrigeration cycle, the inlet (second inlet / outlet) 11a is connected to the high-pressure piping of the outdoor unit, and the outlet (first 3 inlet / outlet) 12a is connected to the low-pressure piping of the outdoor unit, respectively, and fluid (refrigerant) flows from the inlet (second inlet / outlet) 11a (the conduit joint 11) to the inlet / outlet (first inlet / outlet) 10a An example of flowing toward the conduit joint 10) or from the inlet / outlet (first inlet / outlet) 10a (the conduit joint 10) toward the outlet (third inlet / outlet) 12a (the conduit joint 12) As described above, the flow direction (flow path) of the fluid (refrigerant) among the inlet / outlet (first inlet / outlet) 10a, the inlet (second inlet / outlet) 11a, and the outlet (third inlet / outlet) 12a is switched. Of course, this is not a limitation.

1 Three-way selector valve (first embodiment)
2 Three-way selector valve (second embodiment)
3 Three-way selector valve (third embodiment)
5 Valve body 6 Cylindrical base body 6c Fixed stopper convex part (2nd Embodiment)
6d Sleeve portion 7 Valve chamber 8 Valve seat member 9a Upper valve seat 9b Lower valve seat 10, 11, 12 Pipe joint 10a Inlet / outlet (first inlet / outlet)
11a Inlet (second entrance / exit)
12a Outlet (third entrance / exit)
14 Cylindrical holding member 14c Bulkhead 14d Sleeve portion 15 Bearing member 15i Female screw 17 Rotating lift shaft 17a Male screw 19 Support member 20 Upper valve body 20A Upper valve closing spring (upper biasing member)
20a Inner peripheral step part 20b Stopper convex part 20e Upper vertical penetration path (3rd Embodiment)
23 Thrust transmission shaft 30 Upper back pressure chamber 31 Upper pressure equalizing passage 40 Mysterious planetary gear type reduction mechanism 50 Stepping motor (lifting drive unit)
55 Stator 57 Rotor 58 Can 60 Follower member 61 Center hole 61a Upper large-diameter fitting hole 61b Lower large-diameter fitting insertion hole 62 Gutter-shaped member 63 Outer collar-shaped locking portion 65 Connecting rod (connecting member)
66 Through hole 67 Communication hole 70 Lower valve body 70A Lower valve closing spring (lower urging member)
70a Center hole 70b Upper large-diameter fitting insertion hole 70c Movable stopper convex part (2nd Embodiment)
70d side hole (second embodiment)
70e Lower vertical through passage (third embodiment)
80 Lower back pressure chamber 81 Lower pressure equalizing passage

Claims (16)

A valve chamber, a first inlet / outlet opening to the valve chamber, a second inlet / outlet, and a third inlet / outlet, and an upper valve seat provided between the first inlet / outlet and the second inlet / outlet; and A valve body having a lower valve seat provided between the first inlet / outlet and the third inlet / outlet;
An upper valve body disposed in the valve chamber so as to be movable up and down and contacting and separating from the upper valve seat;
A lower valve body that is arranged to be movable up and down in the valve chamber and is in contact with and separated from the lower valve seat;
An upper biasing member for biasing the upper valve body in the valve closing direction;
A lower urging member for urging the lower valve body in a valve closing direction;
Relative movement in the up-and-down direction with respect to the upper valve body, and engagement with the upper valve body to separate the upper valve body from the upper valve seat against the biasing force of the upper biasing member A driven member distributed in
The driven member and the lower valve body can be moved together in order to move the lower valve body away from the lower valve seat against the biasing force of the lower biasing member, and the driven member and the lower valve body And a connecting member that is connected so as to be relatively movable in the up and down direction,
An elevating drive unit for elevating the driven member,
According to the lift amount of the driven member,
While the upper valve body is seated on the upper valve seat, the lower valve body is pushed down from the lower valve seat by the connecting member;
The upper valve body is seated on the upper valve seat, and the lower valve body is seated on the lower valve seat;
A state in which the upper valve body is pulled up from the upper valve seat by the driven member while the lower valve body is seated on the lower valve seat can be selectively taken. Three-way switching valve. Until the lift amount of the driven member reaches a predetermined first lift amount, the lower valve is attached by the connecting member while the upper valve body is seated on the upper valve seat by the biasing force of the upper biasing member. The lower valve body is pushed down from the lower valve seat against the biasing force of the biasing member,
The upper valve body is seated on the upper valve seat by the biasing force of the upper biasing member until the lift amount of the driven member exceeds the first lift amount and reaches a predetermined second lift amount. The lower valve body is seated on the lower valve seat by the biasing force of the lower biasing member,
When the lift amount of the driven member exceeds the second lift amount, the upper urging member is moved by the driven member while the lower valve body is seated on the lower valve seat by the urging force of the lower urging member. 2. The three-way switching valve according to claim 1, wherein the upper valve body is lifted from the upper valve seat against a biasing force.   3. The three-way switching valve according to claim 1, wherein the connecting member is configured by a cylindrical member or a columnar member that extends in the ascending / descending direction.   The connecting member has an upper end inserted into the driven member so as to be relatively movable and engageable in the ascending / descending direction, and a lower end thereof is inserted into the lower valve body so as to be relatively movable and engageable in the ascending / descending direction. The three-way switching valve according to any one of claims 1 to 3, wherein the three-way switching valve is provided.   The three-way switching valve according to any one of claims 1 to 4, wherein the upper urging member is interposed between the upper valve body and the driven member.   The three-way switching valve according to any one of claims 1 to 4, wherein the upper urging member is interposed between the upper valve body and the valve body.   The driven member is inserted into the upper valve body so as to be relatively movable in the up-and-down direction, and is engaged with the upper valve body on the outer periphery of the lower end portion of the driven member according to a lift amount. The three-way switching valve according to any one of claims 1 to 6, further comprising an outer hook-shaped locking portion for lifting the upper valve seat.   The three-way switching valve according to any one of claims 1 to 7, wherein a stopper mechanism that regulates the downward movement of the driven member includes the driven member and the upper valve body.   The three-way switching valve according to any one of claims 1 to 7, wherein a stopper mechanism that controls the downward movement of the driven member includes the lower valve body and the valve body.   An upper pressure equalizing passage in which the chamber diameter of the upper back pressure chamber defined on the upper side of the upper valve body and the aperture of the upper valve seat are set to be the same, and the upper back pressure chamber and the valve chamber are always in communication. And / or the diameter of the lower back pressure chamber defined on the lower side of the lower valve body and the diameter of the lower valve seat are set to be the same, and the lower back pressure chamber The three-way switching valve according to any one of claims 1 to 9, wherein a lower pressure equalizing passage that always communicates with the valve chamber is provided.   The upper pressure equalizing passage includes a through hole provided in the connecting member, a communication hole communicating the through hole and the valve chamber, and an inside of the driven member. The three-way switching valve according to claim 10.   The three-way switching valve according to claim 10, wherein the upper pressure equalizing passage is configured by an upper vertical through passage provided inside the upper valve body.   The lower pressure equalizing passage is configured to include a through hole provided in the connecting member, a communication hole communicating the through hole and the valve chamber, and an inside of the lower valve body. The three-way switching valve according to claim 10.   The three-way switching valve according to claim 10, wherein the lower pressure equalizing passage is constituted by a lower vertical through passage provided inside the lower valve body. The elevating drive unit includes a stepping motor having a stator externally mounted on a can fixed to the valve body, and a rotor rotatably disposed inside the can.
15. The driven member can be moved up and down without rotating through a screw feed mechanism provided between the rotor and the driven member. The three-way selector valve described in the item.   The three-way switching valve according to claim 15, wherein a planetary gear type speed reduction mechanism for reducing and transmitting the rotation of the rotor is interposed between the rotor and the screw feed mechanism.