JP3738289B2 - Three-way switching valve using shape memory alloy - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a three-way switching valve that uses a shape memory alloy to switch a three-way valve depending on a fluid temperature.
[0002]
[Prior art]
One valve body is provided with three inlets / outlets, one of which is used as a fluid inlet and the other two as fluid outlets, and the fluid flowing in from one inlet is activated by any of the outlets by the operation of the internal valve body. Three-way valves that are selectively switched to each other are used in various fields. As an example of the use of such a three-way valve, for example, the one shown in FIG. 5 exists.
[0003]
That is, the tap water supply channel 51 is connected to the first inlet 53 of the four-way valve 52, the water purifier main body 55 containing activated carbon is connected to the connection line from the first outlet 54, and the outlet 56 is connected to the outlet 56. Connected to the inlet 58 of the three-way switching valve 57, the first outlet 60 of the three-way switching valve 57 is connected to the second inlet 61 of the four-way valve 52, and this is supplied as purified water from the second outlet 62. I am doing so. In the case of using such a water purifier, the water purifier main body will become clogged due to the long-term use of the water purifier and the organic matter in the water will gradually become clogged and the function of the activated carbon will deteriorate. The heater provided in 55 is operated and high temperature water is supplied to the activated carbon to activate the filter and clean the water purifier. At this time, since the hot water discharged from the water purifier main body 55 is contaminated, it is preferable to discharge the hot water from another drainage system. Therefore, the three-way switching valve 57 is switched, and the hot water from the inlet 58 is switched to the three-way switching valve 57. The second discharge port 63 is discharged into the water distribution pipe 64.
[0004]
In the three-way switching valve used in such a device, it is necessary to switch the flow path from the first outlet 60 to the second outlet 63 when the heater built in the water purifier main body 55 is operated. In addition, if the operation of the heater is detected or the temperature of the fluid from the water purifier main body 55 is detected and the three-way switching valve 57 is switched by an electromagnetic device, many parts and a control device are required, which is expensive. It must be. As a countermeasure, a three-way switching valve using a shape memory alloy spring has attracted attention as a three-way valve that automatically switches depending on the temperature.
[0005]
On the other hand, in order to automatically switch the three-way valve at a predetermined temperature, there is a need not only in the above-mentioned fields but also in various fields, so various three-way valves using shape memory alloy springs have been proposed. Yes. For example, a three-way switching valve as disclosed in Japanese Utility Model Laid-Open No. 59-51265 has been proposed. This three-way switching valve is provided with an inlet on the central side wall in the cylindrical valve body, a first discharge port on one end surface of the valve body, and a second discharge port on the other end surface. Is provided with a valve body provided with valves facing both discharge ports at both ends in a state of being slidable in a state of being supported by a central support portion, and a bias that constantly biases the valve body in the direction of one discharge port. A spring is provided, and a spring made of a shape memory alloy having a spring constant stronger than that of the bias spring above the predetermined temperature is provided opposite to the spring. Closed by the body, the other outlet is open, and when the temperature of the fluid exceeds a predetermined temperature, the shape memory alloy spring has a strong spring constant, thereby resisting the biasing force of the bias spring. Open the outlet and close the other outlet More, you have to switch the channel.
[0006]
[Problems to be solved by the invention]
In the three-way switching valve using the conventional shape memory alloy spring as described above, particularly when the three-way switching valve is provided in the pipe of the water purifier as described above, the temperature drops below a predetermined temperature from the drain mode. Then, when switching the flow path by the action of the shape memory alloy spring and switching to the water purification mode, at the moment when the valve is switched from the state where the pressure at the inlet is high and the pressure of the drainage path is low, the valve on the water purification side Therefore, the pressure in the drainage channel becomes higher, so that pulsation occurs in the pipe, and a hunting phenomenon in which the valve body repeatedly opens and closes, resulting in vibration and noise. It is understood that this is a water hammer phenomenon caused by a water flow hitting the valve mouth.
[0007]
Accordingly, an object of the present invention is to provide an apparatus that does not generate vibration and noise when a three-way switching valve using a shape memory alloy spring is operated.
[0008]
[Means for Solving the Problems]
In order to solve the above problems, the present invention provides a valve body provided with one inlet and first and second outlets, and a valve body provided with valves opposed to both outlets at both ends. A bias spring is provided to bias the valve body so as to open the first discharge port and close the second discharge port. The spring is opposed to the bias spring and is stronger than the bias spring above a predetermined temperature. In a three-way switching valve using a shape memory alloy spring provided with a constant shape memory alloy spring and closing the first discharge port and opening the second discharge port above the predetermined temperature, the first discharge port side flow A channel buffer is provided in the path.
[0009]
[Means for Solving the Problems]
In order to solve the above-mentioned problems, the present invention enables a valve body provided with a valve facing both discharge ports at both ends to be slidable in a valve body provided with one inlet and first and second discharge ports. A bias spring that biases the valve body so as to open the first discharge port and close the second discharge port, and is opposed to the bias spring and is stronger than the bias spring above a predetermined temperature. In a three-way switching valve using a shape memory alloy spring provided with a constant shape memory alloy spring and closing the first discharge port and opening the second discharge port above the predetermined temperature, the first discharge port side flow A first sliding part having a cross-shaped partition is provided in the passage, extends from a second discharge port provided in the valve body, and is slidable in a second sliding hole, and is formed on the side of the second sliding hole. the shape in which a second sliding portion consisting of a cylindrical valve having a cruciform partition to the second discharge port side It is obtained by constituting the three-way valve with 憶合 gold.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described with reference to the drawings. FIG. 1 shows a first embodiment of the present invention. The operation principle of the three-way switching valve itself is the same as that of the conventional one, but it shows a further improvement. That is, the valve main body 2 having the cylindrical valve chamber 1 is provided with a fluid inlet 3 on the side wall, and a first discharge port 5 is provided on the first end face 4. The valve body 2 has an opening on the second end face 6 side. On the other hand, a discharge port member 8 provided with a flange 7 abuts the flange 7 on the end face and is fixed with a screw 10. An L-shaped drainage channel 11 is formed in the discharge port member 8, and a second discharge port 14 that is open to an end portion 13 that is provided with an O-ring 12 and inserted into the valve chamber 1 is provided. A main valve seat 15 is formed around the second discharge port 14. In the valve chamber 1, there is provided a valve body 16 that secures a sufficient flow path around it and slides in the axial direction in the cylindrical valve chamber. The first sliding portion 17 and the second sliding portion 18 having the first sliding portion 17 extend from the disk portions 20 and 21, and the first sliding portion 17 is in the first sliding hole 22 formed in the first end surface 4 of the valve body 2. The second sliding portion 18 is slidable in the second sliding hole 23 extending from the second outlet 14 portion of the outlet member 8. Further, since each sliding portion 17, 18 has a cross-shaped partition 19, a sufficient fluid flow path is formed in this portion.
[0011]
A first seal ring 25 is provided on the base 24 of the first sliding portion 17, and a second seal ring 27 is provided on the base 26 of the second sliding portion 18. Further, a spring receiver 28 is provided at the center of the valve body 16, and a bias spring 30 is contracted between one side surface of the spring receiver 28 and the inner surface on the first end surface 4 side in the valve chamber 1. A shape memory alloy spring 31 is provided between the other side surface of the spring receiver 28 and the end surface of the discharge port member 8 inserted into the valve chamber.
[0012]
The shape memory alloy spring 31 has a small spring constant in a low temperature state, and is therefore compressed by the biasing force of the bias spring 30, and the valve body 16 is in the state shown in the drawing. Further, when the fluid reaches a predetermined temperature or higher, its shape memory state is entered, and the spring constant increases, so that the valve body 16 is slid to the opposite side against the bias spring 30. In addition, a check valve 33 is provided in the connection pipe 32 of the discharge port member 8 to permit the flow of fluid from the valve chamber side and to block the flow of fluid from the reverse side.
[0013]
When the three-way switching valve 34 as described above is used as the three-way switching valve in the fluid path shown in FIG. 5, in the normal use state of the water purifier, the tap water passes through the four-way valve 52 as described above. Since the spring constant of the shape memory alloy spring 31 is reduced by the surrounding low temperature through the main body 55 and the valve body 16 of the three-way switching valve as described above, the state shown in FIG. It passes through the first discharge port 5 side of the valve body 2 and is further supplied as purified water from another flow path in the four-way valve 52.
[0014]
When the function of the activated carbon has deteriorated due to long-term use of the water purifier, the heater provided in the water purifier main body 55 is operated as described above, and the water in the activated carbon is heated to the boiling state (100 ° C.). The Since the switching temperature of the three-way switching valve is about 40 ° C., when water of 40 ° C. or more flows, the three-way switching valve is switched. At this time, the fluid flowing out from the activated carbon is contaminated because the activated carbon has been purified. When this fluid enters the valve chamber from the inlet of the three-way switching valve, the shape memory alloy spring 31 in the valve chamber is set to be in the shape memory state at that temperature, so the spring constant of the shape memory alloy spring increases. The force causes the valve element to move toward the first discharge port 5 against the biasing force of the bias spring.
[0015]
As a result, the first discharge port 5 is closed by the first seal ring 25, and conversely, the second discharge port 14 that has been closed by the second seal ring 27 is opened, and the activated carbon is purified. The heater in the water purifier main body 55 becomes inoperative, the spring constant of the shape memory alloy spring becomes small, and the valve body is moved to the second discharge port 5 side by the biasing force of the bias spring. At this time, a frictional force is generated when the first sliding portion 17 and the second sliding portion 18 provided at both ends of the valve body 16 slide in the first sliding hole 22 and the second sliding hole 23. , The rapid movement of the valve body is prevented, resulting in a buffering action of the fluid flow.
[0016]
Regardless of the action of the frictional force of the valve body, when the pressure of the water supply line communicating with the water pipe is high and the drainage resistance is large due to the long water distribution line, the pipe line is moved by the movement of the valve body. It is thought that the water hammer phenomenon occurs inside. When such a water hammer phenomenon occurs, the fluid in the pipe line pulsates, but the flow of fluid from the valve chamber side is allowed in the connection pipe 32 of the discharge port member 8, and the reverse side Since the check valve 33 that shuts off the flow of fluid from the pipe is fixed, only one-way flow is allowed in the pipe and the fluid flow is buffered. Generation of pulsation can be prevented, and generation of noise due to the valve body moving left and right in the figure and repeatedly opening and closing the valve can be prevented.
[0017]
2 to 4 show another embodiment of the present invention. In this three-way switching valve, as shown in FIG. 3, the second sliding portion 18 in the three-way switching valve of FIG. 1 is extended, and a cylindrical valve 40 having a cross-shaped partition 19 is provided at the tip thereof. Thus, when the second discharge port 14 is closed by the second seal ring 27, the cylindrical valve 40 closes the opening 41 of the second connection pipe 32 of the discharge port member 8 with its cylindrical surface. A check valve 33 can be provided in the second connection pipe 32 as in the embodiment of FIG.
[0018]
In this embodiment, when the first outlet 5 is closed and the second outlet 14 is released as shown in FIG. In operation, the valve body 16 moves to the left as in the previous embodiment. At this time, the cylindrical valve 40 provided in the second sliding portion 18 opens and closes in a direction crossing the opening 41, so that the seal ring 27 portion closes sufficiently late compared with the valve seat 15 and closes. Therefore, it is possible to prevent a large pressure change from occurring in the fluid pipe line, and to prevent the occurrence of the water hammer phenomenon as described above. In this three-way switching valve, the valve body 16 moves to the left by the movement of the valve body 16, and the state shown in FIG. 4 is reached. The drainage mode is switched to the water purification mode, and the fluid from the water purifier body 55 is purified. Will flow to the side.
[0019]
1, in this embodiment, the fluid flow from the valve chamber side is allowed in the connection pipe 32 of the discharge port member 8, and the fluid flow from the opposite side is blocked. By providing the check valve 33, the buffering effect on the fluid is further improved.
[0020]
【The invention's effect】
Since the present invention is configured as described above, when the three-way switching valve using the shape memory alloy spring is operated, rapid pressure fluctuations in the fluid pipe line can be prevented, and the water hammer phenomenon can be prevented. Generation of vibration and noise can be prevented.
[0021]
By providing the check valve 33 as the flow path buffering portion, the flow of fluid from the valve chamber side is allowed, the flow of fluid from the reverse side is blocked, and the buffering effect on the fluid is further improved.
[0022]
When the flow path buffer part is composed of a sliding part having a cross-shaped partition, a frictional force is generated when sliding in the sliding hole, so that rapid movement of the valve element is prevented and the fluid flow is buffered. Produce. Thereby, a rapid pressure fluctuation in the fluid pipe line can be prevented, and the water hammer phenomenon can be prevented.
[0023]
When the flow path buffer part is composed of a cylindrical valve having a cross-shaped partition, the hot water from the inlet is shut off due to the temperature drop of the water purifier, the shape memory alloy spring is activated and the valve body is closed sufficiently late, It is possible to prevent a large pressure change from occurring in the fluid conduit, and to prevent the occurrence of the water hammer phenomenon.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing an embodiment of the present invention.
FIG. 2 is a cross-sectional view showing a first operating state of another embodiment of the present invention.
FIG. 3 is a partial perspective view of the embodiment.
FIG. 4 is a sectional view showing a second operating state of the same embodiment.
FIG. 5 is a configuration diagram of a fluid pipe line to which the valve of the present invention is applied.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Valve chamber 2 Valve body 3 Inlet 4 1st end surface 5 1st discharge port 6 2nd end surface 7 Flange 8 Discharge port member 11 Drainage channel 12 O-ring 14 2nd discharge port 15 Main valve seat 16 Valve body 17 1st sliding Part 18 Second sliding part 19 Cross-shaped partition 22 First sliding hole 23 Second sliding hole 25 First seal ring 27 Second seal ring 30 Bias spring 31 Shape memory alloy spring 32 Connection pipe 33 Check valve

Claims (2)

In a valve body provided with one inlet and first and second outlets, a valve body provided with valves opposed to both outlets at both ends is provided slidably, and the first outlet is provided to the valve body. A bias spring that biases the outlet direction to open and closes the second discharge port is provided, and a spring made of a shape memory alloy that has a spring constant stronger than the bias spring at a predetermined temperature or more is provided opposite to the bias spring, In the three-way switching valve using a shape memory alloy spring that closes the first discharge port and opens the second discharge port above the predetermined temperature, the first slide having a cross-shaped partition in the first discharge port-side flow path. A moving portion is provided, extends from a second discharge port provided in the valve body, and is slidable within a second slide hole, and has a cross-shaped partition on the second slide hole side and a cross-shaped partition on the second discharge port side using shape memory alloy, characterized in that a second sliding portion consisting of a cylindrical valve having a Three-way valve.   The three-way switching valve using the shape memory alloy according to claim 1, wherein a check valve is provided in a connection pipe connected to the drainage channel.

Images