JP2019157898A - Three-way valve - Google Patents

Abstract

To provide a three-way valve capable of positively keeping a closed state against opposing ports even if it has a simple structure.SOLUTION: Two opposing ports are communicated to each other at positions where they are oppositely faced within a valve chamber and a valve body within the opposing ports is pushed against a valve seat by a biasing member to keep the opposing ports in their closed states. Then, a cam shaft is arranged at the center of the valve chamber and the cam shaft is provided with two cam crests in a line symmetry. With such an arrangement as above, when the cam shaft is rotated to cause a valve body at one opposing port to be moved in a valve opening direction by one cam crest, the valve body at the other opposing port is moved by a biasing member in a valve closing direction and in turn when the valve body at one opposing port is moved by the biasing member in a valve closing direction, it is possible to move the valve body at the other opposing port in the valve opening direction, As a result, it is possible to realize a three-way valve capable of positively keeping the opposing port in the closed state even if its structure is simple.SELECTED DRAWING: Figure 1

Description

  The present invention includes two opposed ports and one non-opposed port that communicate with the valve chamber, and the opposed port communicates with the non-opposed port via the valve chamber by changing the open / closed state of the two opposed ports. The three-way valve can be changed.

  The valve chamber, two opposed ports that communicate with the valve chamber at positions facing each other, one non-opposed port that communicates with the valve chamber at a position different from the two opposed ports, and two valves that open and close the respective opposed ports A three-way valve that includes a body and drives two valve bodies using a cam mechanism is known (Patent Document 1).

  In this three-way valve, when the valve body is brought into contact with the valve seat in order to close the opposed port, the valve body is driven using a cam mechanism, and conversely, the opposed port is opened. Also when separating the valve body from the valve seat, the valve body is driven using a cam mechanism. When one of the opposed ports is opened, the other opposed port is closed. When the other opposed port is opened, one of the opposed ports is closed. Realized.

JP 2013-044410 A

  However, the above-described three-way valve has a problem in that it is difficult to reliably close the opposed port because the valve body is brought into contact with the valve seat using the cam mechanism when the opposed port is closed. was there. That is, if the amount of movement of the valve body by the cam mechanism is too large, the force for bringing the valve body into contact with the valve seat becomes excessive, and the valve body or the valve seat may be damaged. In order to avoid such a situation, if the moving amount of the valve body by the cam mechanism is made too small, the valve body cannot be brought into contact with the valve seat and the opposed port cannot be closed. Thus, although the three-way valve described above has a simple structure, there is a problem that it is difficult to reliably close the opposed port.

  The present invention has been made to solve the above-described problems in the prior art, and an object thereof is to provide a three-way valve capable of reliably closing an opposed port while having a simple structure. And

In order to solve the above-described problems, the three-way valve of the present invention employs the following configuration. That is,
Two opposed ports communicating with the valve chamber at positions facing each other, a non-opposed port communicating with the valve chamber at a position different from any of the two opposed ports, and a first opposed one of the two opposed ports In a three-way valve comprising: a first valve body that opens and closes a port; and a second valve body that opens and closes the other second opposing port of the two opposing ports.
In the first opposed port, the first valve body, a first valve seat against which the first valve body is pressed, and the first valve body are urged in the direction of the valve chamber, A first biasing member that closes the first opposed port by pressing against the seat is provided;
In the second opposed port, the second valve body, a second valve seat against which the second valve body is pressed, and the second valve body are urged toward the valve chamber to urge the second valve. A second biasing member that closes the second opposed port by pressing against the seat is provided;
In the valve chamber,
A cam shaft having a rotation axis orthogonal to a direction in which the first opposed port communicates with the valve chamber and a direction in which the second opposed port communicates with the valve chamber;
A rotating plate that is attached to the camshaft and rotates about the rotating shaft when the camshaft is rotated;
On the one end side of the rotating plate, the first counter port is opened by separating the first valve body from the first valve seat against the force biased by the first biasing member. The first cam mountain is formed,
On the other end side of the rotating plate, the second counter port is opened by separating the second valve body from the second valve seat against the force biased by the second biasing member. A second cam peak to be in a state is formed.

  In the three-way valve of the present invention, the first opposed port and the second opposed port communicate with the valve chamber at a position facing each other. A first valve body is provided in the first counter port, and the first valve body is biased by the first biasing member and pressed against the first valve seat to close the first counter port. Yes. Moreover, the 2nd valve body provided in the 2nd opposing port is also urged | biased by the 2nd urging | biasing member, and is closing the 2nd opposing port by pressing against a 2nd valve seat. Further, a cam shaft with a rotating plate attached is provided in the valve chamber, and the first counter port is formed on one end side of the rotating plate by pushing up the first valve body and separating it from the first valve seat. A first cam crest for opening the second valve body is formed, and the second counter port is opened on the other end side of the rotating plate by pushing up the second valve body and separating it from the second valve seat. For this purpose, a second cam peak is formed.

  In this case, the first valve crest is formed on one end side, and the rotating plate having the second cam crest formed on the other end side is attached to the camshaft, and the camshaft is rotated in the valve chamber. A three-way valve can be realized with a simple structure in which one of the body and the second valve body is separated from the first valve seat or the second valve seat. The first valve body is biased toward the first valve seat by the biasing force of the first biasing member, and the second valve body is biased toward the second valve seat by the biasing force of the second biasing member. Has been. Therefore, if the first cam crest does not separate the first valve body from the first valve seat, or if the second cam crest does not separate the second valve body from the second valve seat, the first cam The force of the urging member or the second urging member urging the first valve body or the second valve body can also ensure that the first opposed port or the second opposed port is closed.

  In the above-described three-way valve of the present invention, the shapes of the first cam crest and the second cam crest provided on the rotating plate are shaped so as to cause the first valve body and the second valve body to move as follows. It is also good. That is, when the first valve body moves in a direction in which the first counter port is opened, the second valve body moves in a direction in which the second counter port is in the closed state, and the first valve body is in the first counter direction. In the case of moving in the direction in which the port is closed, the second valve body may be shaped to move in the direction in which the second opposing port is opened.

  In this way, the movement of the first valve body to open and close the first counter port and the movement of the second valve body to open and close the second counter port are in opposite directions. Can be realized. In addition, by changing the shapes of the first cam peak and the second cam peak, it is possible to adjust the opening ratio between the first counter port and the second counter port.

  Further, in the above-described three-way valve of the present invention, one end side of the cam shaft is pivotally supported by a bearing portion that forms a part of the valve chamber, and the other end side of the cam shaft is provided in a non-opposing port. You may make it support rotatably by abutting the end surfaces of the three support plates formed from three directions.

  If it carries out like this, it will become possible to support the other end side of a cam shaft by the simple structure of making the end surface of three support plates contact | abut from three directions.

  Further, in the above-described three-way valve of the present invention that supports the other end side of the cam shaft by bringing the end surfaces of the three support plates into contact with each other in three directions, the three support plates may be provided at the following positions. good. First, a straight line extending from the position where the first opposed port opens to the valve chamber to the cam shaft and a straight line extending from the cam shaft to the position where the second opposed port opens to the valve chamber are all centered on the cam shaft. Divide the perimeter range into two angular ranges. One of the three support plates is in the following position, that is, the side on which the first cam crest exists when the first cam crest attempts to separate the first valve body from the first valve seat. Is provided within the angle range on the opposite side. The remaining two of the three support plates are provided within an angular range on the side where the first cam crest exists when the first cam crest attempts to separate the first valve body from the first valve seat. You may do it.

  Although the detailed mechanism will be described later, if the three support plates are provided in such a position, the first cam crest is going to push up the first valve body, or the second cam crest is the second valve body. When trying to push up, the large reaction force received by the camshaft can be shared and supported by the two support plates. As a result, the camshaft can be reliably supported even with a simple structure in which the end surfaces of the three support plates are brought into contact with each other from three directions.

It is the exploded assembly figure which showed the internal structure of the three-way valve 1 of a present Example. It is explanatory drawing about the support structure which supports the lower end side (non-opposing port 13 side) of the cam shaft 30 of a present Example with three support plates 15a-15c. It is explanatory drawing about the positional relationship between the three support plates 15a-15c and the central axis Lp of the 1st opposing port 11 and the 2nd opposing port 12. FIG. It is explanatory drawing which showed the operation | movement which the three-way valve 1 of a present Example switches a flow path. It is explanatory drawing about the reason why three support plates 15a-15c can support a load efficiently.

A. Device configuration :
FIG. 1 is an exploded view showing the internal structure of the three-way valve 1 of this embodiment. FIG. 1A shows the external shape of the three-way valve 1 of this embodiment. As shown in the figure, the valve body 10 is shaped like a cross of a large-diameter circular tube and a small-diameter circular tube, and at one end of the large-diameter circular tube is a bearing section having a circular cross section. 20 is inserted, and a cam shaft 30 is inserted through the center of the bearing portion 20. A first opposing port 11 and a second opposing port 12 are respectively formed inside the left and right circular pipes that intersect the large diameter circular pipe of the valve body 10. Further, a non-opposing port 13 is formed on the side of the valve body 10 on the side where the bearing portion 20 is not inserted inside the large-diameter circular tube.

  FIG. 1 (b) shows an exploded view of the three-way valve 1 of this embodiment. As shown in the drawing, an upper portion of a large-diameter circular pipe of the valve body 10 is formed with an inlay portion 10a having an enlarged inner diameter, and the bearing portion 20 is inserted into the inlay portion 10a and assembled. A cylindrical space below the bearing portion 20 serves as the valve chamber 14, and the lower portion of the valve chamber 14 is connected to the cylindrical non-facing port 13 as it is.

  The first facing port 11 has a circular cross section and communicates with the valve chamber 14. An annular first valve seat 11a is formed on the front side where the first opposed port 11 communicates with the valve chamber 14, and a circular first valve hole 11b is formed at the center of the first valve seat 11a. Has been. The second facing port 12 also has a circular cross section, communicates with the valve chamber 14, and has an annular second valve seat 12 a formed on the front side thereof communicating with the valve chamber 14. A circular second valve hole 12b is formed at the center of the seat 12a. Further, the first opposed port 11 and the second opposed port 12 are disposed at coaxial positions, and the central axis Lp of the first opposed port 11 and the second opposed port 12 is the same as that of the cylindrical valve chamber 14. It is orthogonal to the central axis. For this reason, the position where the first counter port 11 communicates with the valve chamber 14 and the position where the second counter port 12 communicates with the valve chamber 14 are positions facing each other.

  In the present embodiment, the first opposed port 11 and the second opposed port 12 are formed to have the same diameter and are provided coaxially, but they need not necessarily have the same diameter. For example, at least one of the inner diameter and the outer diameter may be different. Further, if the position where the first counter port 11 opens to the valve chamber 14 and the position where the second counter port 12 opens to the valve chamber 14 are in a position facing each other, the first counter port 11 The second facing port 12 may communicate with the valve chamber 14 at a different height. Alternatively, if the first opposed port 11 and the second opposed port 12 are in a range where they communicate with each other in the valve chamber 14 facing each other, the first opposed port 11 when viewed from the central axis direction of the valve chamber 14. The second opposed port 12 may not be a straight line but may be bent.

  A first valve body 11v is inserted into the first opposed port 11 toward the first valve seat 11a, followed by a first spring 11s, and finally a first spring receiving portion 11t. 1 spring receiving part 11t is fixed in the 1st counter port 11 with the snap ring which is not illustrated. As a result, the first valve body 11v is urged with an appropriate force by the first spring 11s and comes into contact with the first valve seat 11a to close the first opposed port 11. A rubber seal member 11vs is attached to a portion where the first valve body 11v contacts the first valve seat 11a. Similarly, with respect to the second opposed port 12, the second valve body 12v, the second spring 12s, and the second spring receiving portion 12t are inserted toward the second valve seat 12a, and the second spring is formed by a snap ring (not shown). The receiving portion 12t is fixed in the second opposing port 12. As a result, the second valve body 12v is also urged with an appropriate force by the second spring 12s and comes into contact with the second valve seat 12a to close the second opposed port 12. A rubber seal member 12vs is also attached to a portion where the second valve body 12v contacts the second valve seat 12a. Further, the first spring 11s of the present embodiment corresponds to the “first biasing member” in the present invention, and the second spring 12s of the present embodiment corresponds to the “second biasing member” in the present invention.

  An O-ring 21 is mounted on the outer peripheral side surface of the bearing portion 20. By inserting the bearing portion 20 into the spigot portion 10 a of the valve body 10, the bearing portion 20 is airtight (or liquid-tight) to the valve body 10. Can be assembled. In addition, an elongated cylindrical cam shaft 30 is inserted into the bearing portion 20 at a position coaxial with the cylindrical valve chamber 14. As described above, since the central axis Lp of the first opposing port 11 and the second opposing port 12 is orthogonal to the central axis of the circumferential valve chamber 14, the rotation axis Lc of the cam shaft 30 is also the first opposing port. 11 and the second opposed port 12 are orthogonal to the central axis Lp. The cam shaft 30 can be rotated around the rotation axis Lc.

  A rotating plate 40 is attached to the cam shaft 30. The position where the rotating plate 40 is attached to the cam shaft 30 is determined by attaching the bearing portion 20 to the valve body 10 (with the cam shaft 30 attached). The position is on the center axis Lp of the opposed port 12. Further, the rotating plate 40 has a first cam peak 41 formed on the side facing the first opposing port 11, and a second cam peak 42 formed on the side facing the second opposing port 12. For this reason, when the camshaft 30 is rotated about the rotation axis Lc, the first valve body 11v is separated from the first valve seat 11a by the first cam peak 41, or the second valve body 12v is moved by the second cam peak 42. It can be separated from the second valve seat 12a. This point will be described in detail later. Further, one end side of the cam shaft 30 is pivotally supported by the bearing portion 20, but the other end side of the cam shaft 30 across the rotating plate 40 is a support plate provided in the non-facing port 13 of the valve body 10. (Not shown in FIG. 1).

  2 shows three support plates 15a and 15b provided in the non-facing port 13 of the valve body 10 by breaking the valve body 10 at a position below the first facing port 11 and the second facing port 12. FIG. , 15c. As shown in the figure, the three support plates 15 a, 15 b, and 15 c are erected at equal intervals from the inner peripheral surface of the non-facing port 13 toward the center. The end surfaces of the three support plates 15a, 15b, and 15c are formed in a concave shape. When the bearing portion 20 to which the cam shaft 30 is attached is assembled to the valve body 10, the other end side of the cam shaft 30 has three support surfaces. It will be in the state supported from three directions by the end surface of board 15a, 15b, 15c. Thus, in the three-way valve 1 of the present embodiment, one end side of the cam shaft 30 is pivotally supported by the bearing portion 20, but the other end side of the cam shaft 30 is the end face of the three support plates 15 a to 15 c. It has a simple structure that supports it from three directions. The other end side of the cam shaft 30 can be supported by such a simple structure because the three support plates 15a to 15c are provided at special positions. This point will be described in detail later.

  As shown in FIG. 2, the first cam peak 41 and the second cam peak 42 are substantially fan-shaped, and are monotonous from a small radius Ros on one end side to a large radius Rfo on the other end side. The angle from the one end side to the other end side of the sector is about 75 degrees. The first cam peak 41 and the second cam peak 42 having such a shape are provided at positions that are line-symmetric with each other. The three support plates 15 a to 15 c of the non-facing port 13 are erected at the following positions with respect to the first cam peak 41 and the second cam peak 42.

  FIG. 3 is an explanatory diagram showing the positional relationship between the three support plates 15 a to 15 c erected from the non-facing port 13 and the first cam peak 41 and the second cam peak 42. First, as shown in the figure, the cam shaft 30 is rotated so that the first cam peak 41 faces the first opposing port 11 and the second cam peak 42 faces the second opposing port 12. Then, the end point Pos on the short diameter side (radius Ros side) of the fan-shaped first cam peak 41 and the end point Pos on the short diameter side (radius Ros side) of the second cam peak 42 are the first. The opposing port 11 and the second opposing port 12 are on the same side with respect to the central axis Lp. Therefore, the support plate 15 c is erected toward the cam shaft 30 from the side where the two end points Pos are present. Then, with the support plate 15c as a reference, the support plate 15a and the support plate 15b are erected toward the cam shaft 30 from positions of 120 degrees in the left-right direction. The reason why the three support plates 15a to 15c are provided at such positions will be described in detail later.

B. Operation of the three-way valve 1 of this embodiment:
FIG. 4 is an explanatory view showing the operation of the three-way valve 1 of this embodiment by taking a cross section at the QQ position in FIG. 4A shows a case where the first opposing port 11 is in the open state with the maximum opening and the second opposing port 12 is in the closed state, and FIG. 4B shows the first opposing port 11 and Each of the second opposed ports 12 represents a small open position. FIG. 4C shows a case where the first opposing port 11 is in the closed state and the second opposing port 12 is in the open state with the maximum opening. In the following description, the opening state with the maximum opening is simply referred to as “being fully open”, and the opening state with a small opening is simply referred to as “being in the small opening state”. .

  Further, the three-way valve 1 of the present embodiment is configured such that the fluid that flows into the valve chamber 14 from the first opposed port 11 or the second opposed port 12 flows out from the non-opposed port 13, and the valve chamber 14 from the non-opposed port 13. However, the three-way valve 1 operates in the same manner regardless of how it is used. Therefore, for convenience of explanation, in the following, using the former case, that is, a case where the fluid flowing into the valve chamber 14 from the first opposing port 11 or the second opposing port 12 is caused to flow out from the non-opposing port 13 as an example, The operation of the three-way valve 1 will be described.

  As shown in FIG. 4A, when the first opposed port 11 is in a fully opened state (the second opposed port 12 is in a closed state), the first cam crest 41 resists the urging force of the first spring 11s. The first valve body 11v is separated from the first valve seat 11a by pushing up the one valve body 11v to the fully open position. Further, the second cam crest 42 is disengaged from the second valve body 12v, and as a result, the second valve body 12v is pressed against the second valve seat 12a by the urging force of the second spring 12s. Is closed.

  When the camshaft 30 is rotated clockwise from the state shown in FIG. 4A, the height of the first cam peak 41 that pushes up the first valve body 11v gradually decreases, and the first opposing port 11 Gradually changes from the fully open state to the small open state. On the other hand, the second cam crest 42 comes into contact with the second valve body 12v pressed against the second valve seat 12a and then gradually moves from the second valve seat 12a to the second valve body as the camshaft 30 rotates. Accordingly, the second opposed port 12 gradually changes from a closed state to a small open state. As a result, as shown in FIG. 4B, both the first opposed port 11 and the second opposed port 12 are in a small open state.

  When the camshaft 30 is further rotated in the clockwise direction, as shown in FIG. 4C, the second cam crest 42 further pushes up the second valve body 12v to move the second valve body 12v to the fully open position. On the other hand, the first cam crest 41 is disengaged from the first valve body 11v, and the first valve body 11v is pressed against the first valve seat 11a by the urging force of the first spring 11s. It becomes a state. As a result, contrary to the case of FIG. 4A, the second opposing port 12 is fully open and the first opposing port 11 is closed. When the camshaft 30 is rotated counterclockwise from the state shown in FIG. 4C, the state shown in FIG. 4B (the first opposing port 11 and the second opposing port 12 are both small). Through the open state, the state shown in FIG. 4A (the first counter port 11 is in the fully open state and the second counter port 12 is in the closed state) can be obtained.

  As described above, in the three-way valve 1 of the present embodiment, the first opposed port 11 is opened by rotating the camshaft 30 in the valve chamber 14 and pushing up the first valve body 11v in the first opposed port 11. By pushing up the second valve body 12v in the second opposing port 12, the second opposing port 12 can be opened. The first valve body 11v is pressed against the first valve seat 11a by the urging force of the first spring 11s when the first cam peak 41 is detached from the first valve element 11v and cannot be pushed up from the first cam peak 41. It is done. For this reason, the 1st opposing port 11 can be made into a closed state reliably. Similarly, for the second valve body 12v, when the second cam crest 42 is detached from the second valve body 12v and cannot be pushed up by the second cam crest 42, the second valve seat 12a is urged by the urging force of the second spring 12s. Pressed against. For this reason, the 2nd opposing port 12 can also be made into a closed state reliably.

  Furthermore, in the three-way valve 1 of the present embodiment, the first opposed port 11 and the second opposed port 12 are communicated at positions facing each other in the valve chamber 14. Therefore, one sheet of the first cam peak 41 for pushing up the first valve body 11v of the first counter port 11 and the second cam peak 42 for pushing up the second valve element 12v of the second counter port 12 are provided. It can be formed on both ends of the rotating plate 40. As a result, if one rotating plate 40 is attached to the camshaft 30, the first valve body 11v and the second valve body 12v can be pushed up, so that the structure of the three-way valve 1 can be simplified. As described above, in the three-way valve 1 of the present embodiment, the first opposed port 11 or the second opposed port 12 can be reliably closed while having a simple structure.

  In addition, as shown in FIG. 4 (b), when both the first opposed port 11 and the second opposed port 12 are in the small open state, as the cam shaft 30 is rotated clockwise, the first The opening degree of the first opposing port 11 is continuously reduced, and the opening degree of the second opposing port 12 is continuously increased. Further, as the camshaft 30 is rotated counterclockwise, the opening degree of the first opposing port 11 is continuously increased, and the opening degree of the second opposing port 12 is continuously reduced. For this reason, it can also be used as a mixing valve capable of adjusting the ratio of the inflow amount from the first opposing port 11 and the inflow amount from the second opposing port 12 depending on the angular position of the camshaft 30. In addition, if the shapes of the first cam peak 41 and the second cam peak 42 are changed, the ratio of the inflow amounts of the first opposing port 11 and the second opposing port 12 can be easily set according to the angular position of the cam shaft 30. It becomes possible to adjust.

C. Support structure of the camshaft 30 by the support plates 15a to 15c:
As described above with reference to FIG. 2, the three-way valve 1 of the present embodiment has a structure in which the lower end side (the non-opposing port 13 side) of the cam shaft 30 is supported from three directions by the three support plates 15 a to 15 c. ing. As described above with reference to FIG. 3, one of the three support plates 15 a to 15 c (in this embodiment, the support plate 15 c) has the following position, that is, the first cam crest 41 in the first position. The first cam with respect to the central axis Lp of the first opposing port 11 and the second opposing port 12 when facing the first opposing port 11 and the second cam crest 42 facing the second opposing port 12 The ridge 41 and the second cam ridge 42 are erected toward the cam shaft 30 from the side where the end point Pos on the short diameter side comes. The remaining two (in this embodiment, the support plate 15a and the support plate 15b) are erected from the position of 120 degrees in the left-right direction with respect to the support plate 15c toward the cam shaft 30. The three support plates 15a to 15c are provided at such positions for the following reason.

  FIG. 5 shows the force exerted by the first cam peak 41 and the second cam peak 42 on the first valve element 11v and the second valve element 12v, respectively, when pushing up the first valve element 11v and the second valve element 12v. It is explanatory drawing about. FIG. 5A shows a state where the first valve body 11v in contact with the first valve seat 11a is pushed up by the first cam peak 41 by rotating the cam shaft 30 counterclockwise. ing. When the camshaft 30 is rotated counterclockwise in order to push up the first valve body 11v that is in contact with the first valve seat 11a, first, the end point Pos on the short diameter side of the first cam peak 41 is the first point. It contacts the valve body 11v. Then, by further rotating the camshaft 30 counterclockwise from that state, the first valve body 11v is gradually pushed up by the first cam peak 41. At this time, in addition to the force against the urging force of the first spring 11s, the first cam peak 41 has a force against the pressure of the fluid in the first opposed port 11 (in FIG. 5A) The first valve body 11v is pushed up by the force indicated by the arrow. As a result, the first cam crest 41 receives the force of the same size in the reverse direction (the direction toward the camshaft 30) from the first valve body 11v.

  Further, the first cam crest 41 gradually contacts the first valve body 11v at the end point Pos and then rotates counterclockwise together with the cam shaft 30 to gradually push up the first valve body 11v. A strong force in the lateral direction for the body 11v (force indicated by a rough hatched arrow in FIG. 5A) is applied to the first valve body 11v. As a result, the first cam crest 41 receives the same lateral force in the opposite direction from the first valve body 11v. On the other hand, in a state where the first valve body 11v that is in contact with the first valve seat 11a is being pushed up, the second valve body 12v is pushed up to a nearly fully opened state by the second cam crest 42, and accordingly, the second cam The mountain 42 pushes up the second valve body 12v with a large force for compressing the second spring 12s (a force indicated by a black arrow in FIG. 5A). As a result, the second cam crest 42 also receives force from the second valve body 12v of the same size and in the reverse direction (direction toward the camshaft 30).

  Thus, when the first valve body 11v is to be pushed up from the state in contact with the first valve seat 11a, both the first cam peak 41 and the second cam peak 42 are directed toward the cam shaft 30. The power of Here, the force exerted on the first cam peak 41 by the first spring 11s is smaller than the force exerted on the second cam peak 42 by the second spring 12s. Force due to fluid pressure is also applied. Therefore, the force that the first cam peak 41 receives in the cam shaft 30 direction and the force that the second cam peak 42 receives in the cam shaft 30 direction roughly cancel each other. As a result, the camshaft 30 is mainly subjected to the force indicated by the rough hatched arrow in FIG. 5A (that is, the force that the end point Pos of the first cam peak 41 pushes the first valve body 11v from the side. ) Will be added. In FIG. 5 (a), this reaction force is represented by arrows with fine oblique lines.

  As is clear from FIG. 5A, the reaction force mainly received by the camshaft 30 is divided and supported by the support plate 15a and the support plate 15b. Of course, the direction of the reaction force that the camshaft 30 mainly receives changes as the camshaft 30 rotates, but compared to the angle between the support plate 15a and the support plate 15b (120 ° in this embodiment). Since the angle at which the direction of the reaction force changes is small, the situation in which the reaction force received by the camshaft 30 is shared and supported by the two support plates 15a and 15b does not change.

  FIG. 5B shows a state where both the first valve body 11v and the second valve body 12v are separated from the first valve seat 11a and the second valve seat 12a. In this state, the force exerted on the first cam peak 41 by the first spring 11s and the force exerted on the second cam peak 42 by the second spring 12s are small and moreover cancel each other, so that a large force is exerted on the camshaft 30. There is no participation.

  FIG. 5C shows a state in which the second valve body 12v in contact with the second valve seat 12a is pushed up by the second cam crest 42 by rotating the camshaft 30 clockwise. Yes. Even when the camshaft 30 is rotated clockwise to push up the second valve body 12v that is in contact with the second valve seat 12a, first, the end point Pos of the second cam crest 42 on the short diameter side Comes into contact with the second valve body 12v. And the 2nd valve body 12v is gradually pushed up by rotating the camshaft 30 from the state. At this time, the second cam crest 42 is a force obtained by adding a force that resists the biasing force of the second spring 12s and a force that resists the pressure of the fluid in the second opposing port 12 (in FIG. 5C). The second valve body 12v is pushed up with the force indicated by the white arrow). Furthermore, the second cam crest 42 also applies a force (a force indicated by a rough hatched arrow in FIG. 5C) that pushes the second valve body 12v from the side in the rotation direction to the second valve body 12v. . As a result, the first cam crest 41 has the reaction force of these forces (two forces, the force indicated by the white arrow in FIG. 5C and the force indicated by the arrow with rough diagonal lines), It will be received from the second valve body 12v. Further, in a state where the second valve body 12v that is in contact with the second valve seat 12a is about to be pushed up, the first valve body 11v is pushed up by the first cam peak 41 to near the fully opened state. For this reason, the first cam peak 41 applies a large force (the force indicated by the black arrow in FIG. 5C) for compressing the first spring 11s to the first valve body 11v. A reaction force is received from the first valve body 11v.

  Therefore, in the same manner as in the case where the first valve body 11v is pushed up from the state described with reference to FIG. 5A, that is, the state in which the first valve body 11v is in contact with the first valve seat 11a, Even when trying to push up the second valve body 12v in contact, the force received by the first cam peak 41 and the force received by the second cam peak 42 are roughly canceled out in the direction toward the camshaft 30. As a result, the reaction force of the force indicated by the rough hatched arrow in FIG. 5C is applied to the camshaft 30 (the force indicated by the fine hatched arrow in FIG. 5C). Become. And even when it is going to push up the 2nd valve body 12v contact | abutted to the 2nd valve seat 12a, the reaction force which the camshaft 30 receives mainly is divided and supported by the support plate 15a and the support plate 15b, It has become.

  As described above, in the three-way valve 1 of this embodiment, when the first valve body 11v or the second valve body 12v is to be pushed up from the first valve seat 11a or the second valve seat 12a, a large force is applied to the camshaft 30. The force can be shared and supported by the two support plates 15a and 15b. Therefore, the cam shaft 30 can be reliably supported even with a simple structure in which the end surfaces of the three support plates 15a to 15c are brought into contact with the cam shaft 30.

  Although the three-way valve 1 of the present embodiment has been described above, the present invention is not limited to the above-described embodiment, and can be implemented in various modes without departing from the gist thereof.

1 ... Three-way valve, 10 ... Valve body, 10a ... Inlay part,
11 ... 1st opposing port, 11a ... 1st valve seat, 11s ... 1st spring,
11v ... 1st valve body, 12 ... 2nd opposing port, 12a ... 2nd valve seat,
12s ... 2nd spring, 12v ... 2nd valve body, 13 ... Non-opposing port,
14 ... Valve chamber, 15a-15c ... Support plate, 20 ... Bearing part,
30 ... Cam shaft, 40 ... Rotating plate, 41 ... First cam mount,
42 ... 2nd cam crest, Lc ... rotating shaft.

Claims (4)

Two opposed ports communicating with the valve chamber at positions facing each other, a non-opposed port communicating with the valve chamber at a position different from any of the two opposed ports, and a first opposed one of the two opposed ports In a three-way valve comprising: a first valve body that opens and closes a port; and a second valve body that opens and closes the other second opposing port of the two opposing ports.
In the first opposed port, the first valve body, a first valve seat against which the first valve body is pressed, and the first valve body are urged in the direction of the valve chamber, A first biasing member that closes the first opposed port by pressing against the seat is provided;
In the second opposed port, the second valve body, a second valve seat against which the second valve body is pressed, and the second valve body are urged toward the valve chamber to urge the second valve. A second biasing member that closes the second opposed port by pressing against the seat is provided;
In the valve chamber,
A cam shaft having a rotation axis orthogonal to a direction in which the first opposed port communicates with the valve chamber and a direction in which the second opposed port communicates with the valve chamber;
A rotating plate that is attached to the camshaft and rotates about the rotating shaft when the camshaft is rotated;
On the one end side of the rotating plate, the first counter port is opened by separating the first valve body from the first valve seat against the force biased by the first biasing member. The first cam mountain is formed,
On the other end side of the rotating plate, the second counter port is opened by separating the second valve body from the second valve seat against the force biased by the second biasing member. A three-way valve characterized in that a second cam crest is formed. The three-way valve according to claim 1,
The shapes of the first cam peak and the second cam peak are such that when the first valve element moves in a direction to open the first counter port, the second valve element defines the second counter port. When the first valve body moves in the closed state and the first valve body moves in the direction to close the first opposed port, the second valve body moves in the direction to open the second opposed port. A three-way valve that is formed in a moving shape. The three-way valve according to claim 1 or 2,
One end side of the camshaft is pivotally supported by a bearing portion that forms a part of the valve chamber,
The three-way valve is characterized in that the other end side of the cam shaft is rotatably supported by the end surfaces of three support plates provided in the non-facing port coming into contact with each other from three directions. The three-way valve according to claim 3,
The camshaft is defined by a straight line from the position where the first opposed port opens to the valve chamber to the camshaft and a straight line from the camshaft to the position where the second opposed port opens to the valve chamber. When the range of the entire circumference centered on is divided into two angular ranges,
One of the three support plates is located on a side opposite to the side on which the first cam crest is located when the first cam crest attempts to separate the first valve body from the first valve seat. Provided within the angular range;
The remaining two of the three support plates are within the angular range on the side where the first cam crest is present when the first cam crest attempts to separate the first valve body from the first valve seat. A three-way valve characterized by being provided in

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