Selector valve

Abstract

Provided is a selector valve with which it is possible to accurately dispose a valve body at a rotation position.　The present invention is provided with engagement means 3 that mutually engage at a prescribed position between an outer peripheral section 1A of a valve body 1 and an inner peripheral section 1A of a housing 50.

Description

Switching valve

[0001] The present invention relates to a switching valve, for example, a switching valve that switches a flow path through which a fluid flows.

[0002] In various industrial fields, fluid circuits are used in which a fluid supply source and a fluid load such as a fluid working device or a heat exchanger are connected by a flow path. Some of these fluid circuits are provided with a switching valve that switches the flow path of the working fluid, thereby realizing multiple modes for operating the fluid load using a single fluid circuit.

[0003] For example, the switching valve disclosed in Patent Document 1 includes a valve case having a first valve seat, a second valve seat, and a third valve seat, a main valve element rotatably disposed within the valve case between the first and second valve seats, an auxiliary valve element rotatably disposed within the valve case between the second and third valve seats, and a drive shaft for driving the main valve element and the auxiliary valve element. The first valve seat is provided with first to third ports, and the second valve seat is provided with first and second communication holes.

[0004] The main valve element is switchable between a first communication position, which connects the first port with the second port, and a second communication position, which connects the first port with the third port. The auxiliary valve element is switchable between a blocking position and an open position for the second communication hole. When the auxiliary valve element is in the open position, the first port to the third port are connected via the first communication hole and the second communication hole. This allows switching between a first mode in which the main valve element is in the first communication position and the auxiliary valve element is in the blocking position; a second mode in which the main valve element is in the second communication position and the auxiliary valve element is in the blocking position; and a third mode in which the main valve element is in the second communication position and the auxiliary valve element is in the open position.

[0005] JP 2015-218893 A (page 13, Figure 4)

[0006] In a switching valve such as that described in Patent Document 1, the main valve element can be accurately positioned at the communication position by controlling the rotation angle of the main valve element with a stepping motor. However, external factors such as vibrations can cause the main valve element to deviate from the appropriate communication position, and in this case, there is a risk that the main valve element will remain in this position.

[0007] The present invention has been made in view of the above-mentioned problems, and has as its object to provide a switching valve in which the valve element can be accurately positioned in a rotational position.

[0008] In order to solve the above problems, the present invention provides a switching valve comprising: a housing; a disk-shaped valve element disposed in a valve chamber formed inside the housing and rotatable relative to the housing; and a drive device connected to the valve element to rotate the valve element, wherein the housing is formed with a plurality of ports communicating with the valve chamber for introducing and urging fluids therein, the valve element has a passage, and the rotation of the valve element changes the combination of the plurality of ports to switch the flow path, and the switching valve is provided with engaging means that engages with the outer periphery of the valve element and the inner periphery of the housing at a predetermined position. According to this, by utilizing the engagement position of the engaging means provided at a position radially apart from the rotation axis of the valve element as an initial position, the rotation of the valve element can be controlled from a state where it is set in the initial position, and therefore the valve element can be accurately positioned at a desired rotation position.

[0009] The engaging means may be configured by an elastic portion provided on one of the valve body and the housing, and a step portion provided on the other of the valve body and the housing with which the elastic portion can engage. In this way, the elastic portion reliably engages with the step portion when the engaging means is in the engaged position, and the elastic portion retracts against the biasing force of the elastic portion when the engaging means is in the disengaged position, thereby preventing interference with the rotation of the valve body.

[0010] The elastic portion may include an elastic member and a contact member that is biased by the elastic member and can engage with the step portion. This allows the contact member to have rigidity, eliminating the need to design the elastic member with high rigidity.

[0011] The contact member may engage with the step portion from a direction different from the opening direction of the passage, thereby making the contact member less susceptible to the influence of fluid flowing from the valve chamber into the passage.

[0012] The passage may be formed to penetrate the valve body in the up-down direction, and the step may be formed on the outer peripheral surface of the valve body, whereby gravity is less likely to affect the engagement between the contact member and the valve body.

[0013] The step portion may be formed by cutting out the outer periphery of the valve body, thereby making it possible to make the structure of the switching valve compact.

[0014] The engaging means may be a ratchet mechanism that allows the valve body to rotate to one side and restricts rotation to the other side. In this case, the engaging means engages at the engaging position when the valve body rotates to the other side, and does not engage when the valve body rotates to one side, making it easy to control the setting of the valve body to the initial position.

[0015] The valve may further include a motor that drives the valve element, and a detection unit that detects the engagement state of the engagement means based on the value of a current to the motor. In this way, the engagement state of the engagement means can be detected by monitoring the value of the current to the motor, thereby simplifying the structure of the switching valve.

[0016] Fig. 1 is a perspective view showing a switching valve in Example 1 of the present invention. Fig. 2 is a cross-sectional view showing a switching valve in Example 1. Fig. 3 is a top view of an upper cover in Example 1. Fig. 4 is a top view of a lower cover in Example 1. Fig. 5 is a top view of a case and a valve body in Example 1. (a) is a schematic view showing an engaged state of a ratchet mechanism, and (b) is a schematic view showing a disengaged state of the ratchet mechanism. Fig. 6 is a cross-sectional view showing a switching valve in Example 2 of the present invention.

[0017] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A switching valve according to an embodiment of the present invention will be described below with reference to the accompanying drawings.

[0018] The switching valve according to the first embodiment will be described with reference to Fig. 1 to Fig. 7. In the following description, the top and bottom of Fig. 2 will be referred to as the top and bottom of the switching valve. Specifically, the top side of the paper on which the motor is located will be referred to as the top side of the switching valve, and the opposite side, the bottom side of the paper, will be referred to as the bottom side of the switching valve.

[0019] The switching valve V of the present invention is used to select one of a plurality of modes of the fluid circuit and to switch the flow path through which the working fluid flows.

[0020] As shown in FIGS. 1 and 2, the switching valve V is mainly composed of a valve body 1, a housing 5, a drive unit 6, and a ratchet mechanism 3 (see FIG. 5) serving as an engagement means.

[0021] The housing 5 is made up of a disk-shaped upper cover 5A and lower cover 5B, and a cylindrical case 5C. The upper cover 5A, lower cover 5B, and case 5C are made of a metal material or a resin material.

[0022] The upper cover 5A is fastened to the case 5C with bolts (not shown) to close the upper opening of the case 5C, and the lower cover 5B is fastened to the case 5C with bolts (not shown) to close the lower opening of the case 5C.

[0023] 3, a first port P10 is provided in the top cover 5A, penetrating it in the vertical direction. The first port P10 functions as an inlet port through which the working fluid discharged from an external fluid load (not shown) flows into the switching valve V.

[0024] A through-hole 5Ab is provided in the center of the upper cover 5A, and a drive shaft 6A serving as a rotation shaft, as will be described later, is rotatably inserted therethrough (see FIG. 2).

[0025] As shown in FIG. 4, the lower cover 5B is provided with a second port P20, a third port P30, a fourth port P40, and a fifth port P50 that penetrate the lower cover 5B in the vertical direction.

[0026] The second port P20 to the fifth port P50 are arranged at uneven intervals in the circumferential direction on a circle of the same radius from the center of the bottom cover 5B. Specifically, the second port P20 is located at approximately the 9 o'clock position on the bottom cover 5B. The third port P30 is located approximately 40 degrees clockwise from the second port P20. The fourth port P40 is located approximately 95 degrees clockwise from the third port P30. The fifth port P50 is located approximately 100 degrees clockwise from the fourth port P40.

[0027] These second port P20 to fifth port P50 function as outflow ports through which the working fluid in the switching valve V flows out toward an external fluid load (not shown).

[0028] The lower cover 5B has a recess 5Bb at its center, which is open upward, into which the lower end of the drive shaft 6A is rotatably inserted (see FIG. 2).

[0029] Next, the valve body 1 will be described with reference to FIG.

[0030] The valve body 1 is disk-shaped and has a through-hole 1a and an insertion hole 1b as passages.

[0031] The insertion hole 1b passes through the center of the valve body 1, and the drive shaft 6A is press-fitted into the insertion hole 1b, thereby allowing the valve body 1 to rotate together with the drive shaft 6A.

[0032] The through hole 1a can be selectively connected to any one of the second port P20 to the fifth port P50 by changing the rotational position of the valve body 1.

[0033] A step 3A that forms part of a ratchet mechanism 3 (described later) is formed on the outer circumferential portion 1A of the valve body 1. This step 3A is composed of an outer circumferential surface 1c of the valve body 1, an end face 3Aa that extends radially inward from the counterclockwise end of the outer circumferential surface 1c in a top view, and an inclined surface 3Ab that extends radially outward from the inner end of the end face 3Aa in a counterclockwise direction in a top view and is continuous with the outer circumferential surface 1c.

[0034] Returning to FIG. 2, the drive unit 6 is mainly composed of a drive shaft 6A and a drive device 6B.

[0035] The drive unit 6B is a device that transmits an external driving force to the outer peripheral surface of the upper end of the drive shaft 6A. For example, the drive unit 6B in this embodiment includes a stepping motor, a gearbox, and a rotary encoder, and is capable of rotating the valve element 1 to any rotation position around the drive shaft 6A. A detector 7 that detects the current value to the stepping motor is connected to the drive unit 6B.

[0036] The switching valve V of this embodiment 1 is capable of changing the destination of the working fluid flowing in from the first port P10 by changing the rotational position of the valve body 1 and appropriately selecting the second port P20 to the fifth port P50 to which the through hole 1a is connected.

[0037] Next, the ratchet mechanism 3 will be described with reference to FIGS.

[0038] The ratchet mechanism 3 is mainly composed of a step portion 3A, a hinge piece 3B as a contact member, and a torsion spring 3C as an elastic member.

[0039] As described above, the step portion 3A is formed by cutting out a part of the outer periphery 1A of the valve body 1.

[0040] The hinge piece 3B is made of resin, metal, or the like, and is attached to be swingable about a fixed shaft 5Cb extending vertically and provided in a groove 5Ca in the inner periphery 5CA of the case 5C.

[0041] The torsion spring 3C has its torsion portion 3Ca fitted onto the fixed shaft 5Cb, one arm 3Cb contacting the peripheral side wall 5Cc forming the groove 5Ca, and the other arm 3Cc fixed to the hinge piece 3B, so that the end of the hinge piece 3B opposite the fixed shaft 5Cb is biased radially inward.

[0042] Referring to FIG. 7, hinge piece 3B is disposed above torsion spring 3C, and the load of hinge piece 3B presses down on torsion spring 3C, thereby preventing deformation of torsion spring 3C in the vertical direction.

[0043] Additionally, washers 3D and 3E are disposed on the fixed shaft 5Cb below the torsion spring 3C and above the hinge leaf 3B, restricting the vertical movement of the hinge leaf 3B and the torsion spring 3C. The material of the washers 3D and 3E is not particularly limited, but by using a low-friction material such as fluororesin, they are less likely to impede the rotation of the hinge leaf 3B and the torsion spring 3C.

[0044] As shown in FIG. 5, the hinge piece 3B and the torsion spring 3C are provided at a position slightly closer to the 1 o'clock side than the 12 o'clock position in a top view on the inner circumferential portion 5CA of the case 5C.

[0045] Referring to Figure 6 (a), the hinge piece 3B and the torsion spring 3C are capable of engaging with the end face 3Aa of the step portion 3A of the valve body 1, which rotates counterclockwise when viewed from above, and are configured to restrict further counterclockwise rotation of the valve body 1.

[0046] 6(b), the hinge piece 3B and the torsion spring 3C are configured to allow the valve body 10 to rotate clockwise when viewed from above. The step portion 3A has an inclined surface 3Ab, which allows the hinge piece 3B to smoothly come off the step portion 3A (see FIG. 6(a)).

[0047] In such a switching valve V, the valve element 1 often deviates from the desired rotation position due to external factors such as vibration. In the switching valve V of this embodiment, for example, control is performed to set the valve element 1 to its initial position at predetermined time intervals.

[0048] When the valve disc 1 is set to its initial position using the ratchet mechanism 3 from a state in which the hinge piece 3B is not engaged with the step portion 3A and the valve disc 1 is at any rotational position (for example, the state shown in FIG. 6(b)), the valve disc 1 is rotated clockwise (i.e., rotated to the other side) as viewed from below until the hinge piece 3B engages with the step portion 3A, as shown in FIG. 6(a). When the hinge piece 3B engages with the step portion 3A, the detector 7, which detects the current value of the stepping motor of the drive unit 6B, detects a current value exceeding a predetermined threshold. This stops the stepping motor of the drive unit 6B, and the valve disc 1 is set to its initial position.

[0049] In this way, the valve body 1 can be set to the initial position, and from the state in which the valve body 1 is set to the initial position, the valve body 1 can be controlled to rotate to any rotation position as appropriate, so that the valve body 1 can be accurately positioned at the desired rotation position.

[0050] In addition, the engagement position of the ratchet mechanism 3 provided on the outer periphery 1A of the valve body 1, which is radially away from the drive shaft 6A, i.e., the position where the hinge piece 3B and the step portion 3A engage, is used as the initial position, so the valve body 1 can be accurately set to the initial position.

[0051] Furthermore, since the ratchet mechanism 3 is used to mechanically restrict the rotation of the valve element 1, the valve element 1 can be accurately positioned in the initial position.

[0052] Furthermore, the engagement state of the hinge piece 3B and the step portion 3A can be detected by monitoring the current value to the stepping motor of the drive unit 6B using the detection unit 7, so the structure of the switching valve V can be simplified without using high-performance sensors, etc.

[0053] Furthermore, when the ratchet mechanism 3 is in the engaged position, the torsion spring 3C ensures that the hinge piece 3B engages with the step portion 3A, and when the ratchet mechanism 3 is in the disengaged position, the hinge piece 3B retracts from the step portion 3A against the biasing force of the torsion spring 3C, thereby preventing interference with the rotation of the valve body 1. Furthermore, the biasing force from the torsion spring 3C is always applied to the outer circumferential surface 1c of the valve body 1, so the operation of the valve body 1 is stable.

[0054] Furthermore, the torsion spring 3C and the hinge piece 3B form an elastic part that can engage with the step portion 3A. This allows the hinge piece 3B to have rigidity, so there is no need to design the torsion spring 3C to have high rigidity.

[0055] Furthermore, because the hinge pieces 3B engage with the step portion 3A from a radial direction, which is a direction different from the axial direction in which the through hole 1a is formed, it is possible to reduce the effect that the fluid pressure of the working fluid flowing through the through hole 1a, which is provided in the axial direction, has on the engagement state between the hinge pieces 3B and the step portion 3A. Furthermore, because the load of the valve body 1 does not act on the hinge pieces 3B, and similarly, the load of the hinge pieces 3B does not act on the valve body 1, it is possible to reduce the effect that gravity has on the engagement state between the hinge pieces 3B and the step portion 3A.

[0056] Furthermore, since the step portion 3A is formed by cutting out the outer peripheral portion 1A of the valve body 1, the structure of the switching valve V can be made more compact than when the step portion 3A is provided by protruding outward from the outer peripheral surface of the valve body 1.

[0057] Furthermore, the ratchet mechanism 3 allows the valve element 1 to rotate to one side and restricts rotation to the other side, so that when the valve element 1 rotates to the other side, the hinge piece 3B and the step portion 3A engage at the engagement position, but when the valve element 1 rotates to one side, the hinge piece 3B and the step portion 3A do not engage with each other. This makes it easy to control the valve element 1 to set it to its initial position.

[0058] In particular, the valve body 1 can rotate 360 ​​degrees to one side, and rotation to the other side is restricted at only one point in the circumferential direction, so the valve body 1 has a high degree of rotational freedom, which is useful in a configuration such as this embodiment 1 in which the through hole 1a of the valve body 1 is connected to the second port P20 to the fifth port P50 that are unevenly arranged in the lower cover 5B.

[0059] In addition, although the present embodiment has been described as an example in which one disc is provided as the valve body, the present invention can also be applied to cases in which there are multiple discs, as long as one ratchet mechanism is provided for the disc directly connected to the drive unit. For example, if there are two discs and each is connected to a drive unit, one ratchet mechanism can be provided for each disc.

[0060] Next, a switching valve according to a second embodiment will be described with reference to Fig. 8. Note that the description of the same configuration as in the first embodiment will be omitted.

[0061] 8, the switching valve V2 has a plurality of inlet ports P1 and outlet ports P2 (only one of each port is shown) provided on the case 50C of the housing 50. No ports are provided on the upper cover 50A or the lower cover 50B.

[0062] The valve body 10 is provided with communication passages 10A and 10B (only a portion of each communication passage is shown) that connect the desired inlet port P1 and outlet port P2. By rotating the valve body 10, the combination of the inlet port P1 and outlet port P2 that communicate with the communication passages 10A and 10B can be changed.

[0063] An upwardly projecting protrusion 10a is provided on the top surface of the valve body 10. Furthermore, a radially inwardly projecting protrusion 50Ca is provided on the inner peripheral surface of the case 50C. The protrusion 10a comes into contact with the protrusion 50Ca when the valve body 10 rotates. The protrusion 10a and the protrusion 50Ca function as an engagement means.

[0064] The valve element 10 is rotated clockwise or counterclockwise from any rotational position until the protruding piece 10a engages with the protruding piece 50Ca, and when the protruding piece 10a engages with the protruding piece 50Ca, the detector 70, which detects the current value of the stepping motor of the drive device 60, detects a current value exceeding a predetermined threshold value. This stops the stepping motor of the drive device 60, and the valve element 10 is set to the initial position.

[0065] Although the embodiments of the present invention have been described above with reference to the drawings, the specific configuration is not limited to these embodiments, and the present invention also includes modifications and additions that do not deviate from the gist of the present invention.

[0066] For example, in the first embodiment, the engaging means is described as a ratchet mechanism, but it is not limited to a ratchet mechanism and can be freely changed as long as it engages between the outer periphery of the valve disc and the housing when the valve disc is in its initial position. For example, the contact member may be a ball, the elastic member a coil spring, the step portion a recess provided in the valve disc, etc.

[0067] In the first embodiment, the engaging means is engaged between the outer peripheral surface of the valve disc and the inner peripheral surface of the housing, which is advantageous in that the axial and radial dimensions of the switching valve can be made compact, but the engaging means does not necessarily have to be engaged between the outer peripheral surface of the valve disc and the inner peripheral surface of the housing. For example, a contact member provided on the inner peripheral part of the housing may be engaged with a step provided on the upper surface of the valve disc that is radially outer than the passage.

[0068] In addition, in the first embodiment, a torsion spring is used as the elastic member, but it may be replaced with a leaf spring or the like. Also, if the elastic member has sufficient rigidity, the contact member may be omitted and the valve body may be engaged only with the elastic member. In other words, the elastic member may also serve as the contact member.

[0069] Furthermore, in the first embodiment, a form in which a hinge piece is used as a contact member is exemplified, but this is not limiting, and the contact member may be, for example, an elastic member provided on the inner periphery of the housing so as to be crushed when one side of the valve body is rotated, and to return elastically to engage with the step portion of the valve body when the other side of the valve body is rotated.

[0070] The shape of the step is not limited to that of the first embodiment, and may be any shape that allows the contact member to engage when the valve body rotates to the other side. A plurality of step portions may be provided in the circumferential direction of the outer periphery of the valve body.

[0071] In addition, in the above-mentioned Example 1, an example was given in which the hinge piece and the torsion spring are provided on the housing side and the step portion is provided on the valve body side, but it is also possible that the contact member and the elastic member are provided on the valve body and the step portion is provided on the housing side.

[0072] In addition, although the first embodiment exemplifies a configuration having one inlet port and four outlet ports, the numbers of inlet ports and outlet ports can be freely changed as long as one or more of one is present and the other is present as two or more. Furthermore, the numbers of inlet ports and outlet ports do not have to be different, and the same number of ports may be provided.

[0073] The valve body is not limited to a disk shape, but may be freely changed to, for example, a fan shape, an arc shape, a C-shape, etc. Also, the valve body does not have to be provided with a passage.

[0074] DESCRIPTION OF SYMBOLS 1 Valve body 1A Outer periphery 1a Through hole (passage) 3 Ratchet mechanism (engagement means) 3A Step 3B Hinge piece (contact member, elastic portion) 3C Torsion spring (elastic member, elastic portion) 5 Housing 5CA Inner periphery 6 Drive unit 6A Drive shaft (rotating shaft) 6B Drive device (motor) 7 Detection section V Switching valve

Claims

1. A switching valve comprising a housing, a disk-shaped valve body disposed in a valve chamber formed inside the housing and relatively rotating with respect to the housing, and a driving device connected to the valve body to rotate the valve body. A plurality of ports communicating with the valve chamber and for introducing and discharging fluid are formed in the housing. The valve body has a passage, and by changing the combination of the plurality of ports as the valve body rotates, the flow path can be switched. An engaging means is provided at a predetermined position between the outer peripheral portion of the valve body and the inner peripheral portion of the housing for engaging with each other.

2. The switching valve according to claim 1, wherein the engaging means is composed of an elastic portion provided on one of the valve body and the housing, and a stepped portion provided on the other of the valve body and the housing with which the elastic portion can engage.

3. The switching valve according to claim 2, wherein the elastic portion includes an elastic member and a contact member urged by the elastic member and capable of engaging with the stepped portion.

4. The switching valve according to claim 3, wherein the contact member engages with the stepped portion from a direction different from the opening direction of the opening in the passage.

5. The switching valve according to claim 4, wherein the passage is formed to penetrate in the vertical direction of the valve body, and the stepped portion is formed on the outer peripheral surface of the valve body.

6. The switching valve according to claim 5, wherein the stepped portion is formed by notching the outer peripheral portion of the valve body.

7. The switching valve according to any one of claims 2 to 6, wherein the engaging means is a ratchet mechanism that allows rotation of the valve body in one direction and restricts rotation in the other direction.

8. The switching valve according to claim 1, further comprising a motor for driving the valve body, and a detection unit for detecting the engagement state of the engaging means based on the current value applied to the motor.

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