JPH0324381A - Three-way valve - Google Patents

Abstract

PURPOSE:To miniaturize and lighten a three-way valve, reduce its noise and enhance its profitability by switching the switching direction of a delivery port by means of electricity transmission to a switching means made of an electrothermal shape memory alloy and extended with one end fixed to a valve and the other end to a frame. CONSTITUTION:A linear material 8 made of an electrothermal shape memory alloy is constantly held in a low temperature relaxed state and is stretched and deformed more than its basic form by the resilient force of a spring 6, and a valve 5 is energized leftward and a rubber 11 provided at the end of the valve 5 is seated on the inner end portion of a delivery port 3 so that the delivery port 3 is closed. An auxiliary flow passage 10 and a flow passage 13 are communicated with each other so that a delivery port 4 is opened. The linear material 8 is caused to generate heat by means of electricity transmission and is deformed and recovers to its contracted form at a predetermined temperature. The valve body 5 shifts to the delivery port 4 side and the delivery port 4 is closed, while the delivery port 3 is opened. The three-way valve is thus miniaturized and its working noise, vibration by impact and power consumption are reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a three-way valve that is installed in a pipe or the like that controls a fluid flow path and switches the flow path of a JF fluid. <Prior art> This type of three-way valve has a frame with a flow path and three ports communicating with the flow path, and the fluid introduced from one of the inlet ports is directed to one of the two discharge ports. It is equipped with a valve body that switches the flow path to selectively discharge from either side. The valve body is normally elastically biased in the direction of closing one discharge port and opening the other discharge port by a spring disposed at an appropriate position on the frame body. On the other hand, when switching the flow path, the valve body is slid by a solenoid attached to the frame in the direction of closing the other discharge port and opening one discharge port, thereby selecting the fluid flow path. It is known that there is a structure L7 that can be switched quickly. <Problems to be Solved by the Invention> However, such conventional three-way valves have a structure in which a solenoid is used as a means for switching the valve body, and therefore, there are various problems as follows. Ta. That is, since a coil or the like for controlling part of the solenoid is attached to the frame, the device becomes large and heavy. In addition, since the valve device must be installed in consideration of the influence of the magnetic field on the surrounding area, the mounting position of the valve device is restricted, and as a result, its usage is also restricted. Furthermore, when the valve body slides, the valve body moves rapidly and hits the valve seat, etc., which generates operating noise and shock vibrations, and generates a large amount of noise, which also limits the application. In addition, solenoids consume a large amount of electricity, making them economically disadvantageous. Therefore, in view of the above-mentioned conventional circumstances, the present invention adopts a valve body switching means using a conductive shape memory alloy instead of a solenoid, thereby achieving miniaturization, weight reduction, versatility, and noise reduction. The purpose is to provide a three-way valve with improved economic efficiency. <Means for Solving the Problems> For this reason, the three-way valve of the present invention has three ports that communicate with the flow path formed inside the r frame, and two ports that allow fluid flowing in from one of the introduction ports. In a three-way valve comprising a valve body for switching a flow path within the frame so as to selectively discharge from one of the two discharge ports, the valve body normally closes one discharge port. and a spring for resiliently biasing the other discharge port in the direction of opening, and an electrically heated shape memory alloy whose one end is fixed to the valve body and the other end is fixed and stretched to the frame. 1. A three-way valve, characterized in that the switching means is configured to move the valve body against the spring by energizing the switching means to switch the opening/closing direction of the discharge port. The precepts are as follows.

In this configuration, when the valve body is not energized, the energized heat-generating shape-memory alloy wire is in a relaxed state, so it is biased by the elastic force of the spring and closes one discharge port. are doing. In this state, since the other discharge port is open, the other discharge port and the introduction port are in communication. Therefore, the fluid introduced from the introduction port reaches the other discharge port and is discharged from there. On the other hand, when electricity is applied to the wire made of the current-heating shape memory alloy, the wire generates heat due to its own electrical resistance,
When the temperature exceeds a predetermined temperature, it deforms into a pre-memorized contracted shape against the elastic force of the spring. This contraction and deformation of the wire causes the valve body to slide in the direction opposite to the biasing direction of the spring, so that, contrary to the above, the other discharge port is closed and one discharge port is opened. Therefore, the fluid introduced from the introduction port reaches one of the discharge ports via the flow path of the frame and is discharged. When the electric current is turned off to the shape memory alloy wire that generates electricity, the temperature of the wire rapidly decreases to below a predetermined temperature due to the cooling effect caused by the passage of the fluid. the result,
As the wire is elongated and deformed to its original length again by the return force of the spring, the valve body returns to its normal position where it comes into pressure contact with one of the discharge ports and closes the port. <Example> Next, an example of the present invention will be described based on the drawings. In Figures 1 to 4, 1 is a frame with one introduction port 2 and two discharge ports 3.4, and 5 is an introduction port 2.
a valve body that switches the flow path within the frame l to selectively guide the fluid introduced from the discharge port 3.4 to either one of the discharge ports 3.4;
6 is a spring for normally biasing the valve body 5 in a direction that closes one discharge port 3 and opens the other discharge port 4; 8 has one end fixed to the valve body 5; It is a wire rod made of a shape memory alloy of an energized heat generation type whose other end is stretched and fixed to the frame body 1, and when energized, it contracts and deforms into the matrix shape due to self heat generation, and the valve body 5 The valve body is slid in the direction of closing the other discharge port 4 and opening one discharge port 3, and the valve body switching stage 7
It is in the form of Here, the frame 1 is made of a conductive material such as metal,
Discharge ports 3 and 4 are provided at both ends, respectively, and an introduction port 2 is provided at the same end in the orthogonal direction. There is a valve body 5 inside the frame l.
A main flow path 9 is formed in which the discharge ports 3 and 4 and the introduction port 2 are communicated from three directions. The other discharge port 4 is connected to the main flow channel 9 via a sub flow channel 10 formed in the frame l. This sub-flow path 10 is formed between a small tube portion 10a that communicates with the discharge port 4 at one end, a small chamber 10b that communicates with the other end of the small tube portion 10a, and between the small chamber 10b and the main flow path 9. A plurality of small holes 1 connecting both flow channels provided in the partition wall 1
0c and is sidelined by. The frame body 1 includes a frame structure member IA that includes an introduction port 2, a discharge port 3, and a portion that forms a part of the main flow path 9, and a cylindrical portion that forms the other portion of the main flow path 9. A frame member IB having a wall 18 and a recess la, and a small tube part L.
It is composed of a frame structure member IC provided with Oa and a discharge port 4, and these frame structure members IA, IB, I
The valve bodies 5 are assembled by being screwed together by threaded parts provided at their respective joint parts.In addition, a sealing O-ring may be provided at each assembly part.The valve body 5 is made of conductive material. The cylindrical part 5a is made of a member such as metal.
, the cylindrical portion 5b and the cone-shaped rubber 11 attached to the tip of the cylindrical portion 5a. Further, four insulating spacers l2 extending in the axial direction are installed on the outer circumferential surface of the valve body 5, respectively, and are spaced apart by 90 degrees.
The outer surface of the insulating spacer l2 is slidably in contact with the inner circumferential surface of the main flow path 9 in the longitudinal direction, and a predetermined flow path l3 is formed between the outer circumferential surface of the valve body 5 and the inner circumferential surface of the frame 1. (See Figure 4). The spring 6 is housed inside the cylindrical portion 5b of the valve body 5, has one end in contact with the inner bottom surface of the cylindrical portion 5b, the other end in contact with the inner surface of the wall portion 18, and has a rubber tip. The valve body 5 is elastically biased in the direction in which the valve body 11 is seated at the inner end of the discharge port 3. Reference numerals 19 and 20 are insulating members disposed to prevent electrical continuity between the spring 6 and the valve body 5 and the frame body 1. However, when the spring 6 is formed of a non-conductive material, the insulating material 19 may be omitted. Incidentally, the insulating member 20 also serves as a sealing material when the valve body 5 comes into contact with the inner surface of the wall portion l8. The electric heating type shape memory alloy (
For example, a wire rod 8 made of (TI-Nl shape memory alloy) is disposed inside the cylindrical portion 5b of the valve body 5 substantially along the axis. Further, the one end portion 8a is connected to the cylindrical portion 5 of the valve body 5.
The other end 8b passes through the wall 18 and is fixed on the outer side of the wall l8. The wire rod 8 made of the current-generating shape memory alloy generates heat when it is energized, and when the heat generated by itself reaches a predetermined temperature or higher, it shrinks and deforms into a pre-memorized matrix shape. When the power supply is stopped and the temperature drops below a predetermined temperature due to no longer generating heat, the spring 6 is expanded by the restoring force of the spring 6 and returns to its original deformed shape. Further, a lead wire l6 is connected to the valve body 5, which passes through a hole 14 formed in the peripheral wall of the frame l and filled with an insulating material 15. Further, a lead wire 17 is connected to the frame l. The pair of glued M16.17 is connected to an external power supply circuit (not shown) to be energized, and the opening/closing of energization and voltage adjustment are controlled by the t-source circuit. ．． Next, we will explain the action of this three-way valve. Normally, the wire 8 is in a low-temperature relaxed state with no current applied, so it receives the elastic force from the spring 6 and is elongated and deformed more than its parent shape, so the valve body 5 has the shape shown in FIG. The valve body 5 is biased to the left, and the rubber 1l at the tip of the valve body 5 is seated on the inner end of the discharge port 3, thereby airtightly closing the discharge port 3. On the other hand, in this state, the auxiliary flow path 10 and the flow path 13 formed between the outer circumferential surface of the valve body 5 and the inner circumferential surface of the frame l are in communication with each other.
The discharge port 4 is opened, and the discharge port 4 and the introduction port 2 are opened.
The two are connected. Therefore, the fluid introduced from the introduction port 2 flows through the flow path l3 between the outer circumferential surface of the valve body 5 and the inner circumferential surface of the frame l.
and reaches the discharge port 4 through the sub-flow path 10, from which it is discharged. On the other hand, when the power supply circuit is turned on and electricity is applied to the current-heating type shape memory alloy wire 8 through the lead wires 16 and 17, the wire 8 generates heat and the second
As shown in the figure, it is heated by the heat it generates,
When it reaches a predetermined temperature, it recovers and deforms to the pre-memorized contracted shape. Note that this shape recovery force is significantly larger than the elastic force of the spring 6. This contraction and deformation of the wire 8 causes the valve body 5 to slide toward the discharge port 4 side (right side in FIG.
8. Contacts the inner surface. In this manner, the rear end surface of the valve body 5 abuts against the inner surface of the wall portion 18 so as to surround and enclose the small hole 10c, thereby cutting off communication between the flow path 13 and the sub flow path 10, and discharging the discharge port 4.
is closed, while discharge port 3 is opened. Therefore,
The fluid introduced from the introduction port 2 reaches the discharge port 3 via the main flow path 9, and is discharged from there. In such a state, when the power supply circuit is turned off and the power supply to the wire rod is stopped, the generation of heat in the wire rod 8 is stopped and the temperature is lowered to below a predetermined temperature, so that the elastic force of the spring 6 causes the wire rod 8 to return to its original elongated shape. At the same time, the valve body 5 is urged toward the discharge port 3 side (left side in FIG. 1) and closes the discharge port 3 as described above. According to the three-way valve configured as described above, the wire rod 8 made of an energized heat-generating shape memory alloy is used as the means 7 for switching the opening/closing direction of the valve body 5, so that the device can be made smaller and its weight can be reduced. In addition, unlike conventional solenoid drive, there is no magnetic field effect on the area around the valve, so there are no restrictions on the installation position of the device, and there are no restrictions on the application. Furthermore, when the valve body 5 slides, the valve body 5 moves slowly and closes the discharge port 4, so no operation noise or impact vibration is generated, and the noise is small, so there are no restrictions on the application. I don't accept it. Furthermore, the wire rod 8 made of a shape memory alloy that generates electricity when heated consumes less power than a solenoid, and is therefore economically advantageous. Note that the structure of the above embodiment does not limit the present invention in any way. For example, in this embodiment, the valve body 5 and the frame l
Lead wire 16. Although the wire 8 is energized by connecting the wire 8, the present invention is not limited to this, and a structure in which the wire 8 is energized by directly connecting a lead wire or the like may be used. Effects of the Invention> As explained above, according to the three-way valve of the present invention, the valve body switching means using a conductive heat-generating shape memory alloy is used as the actuator for driving the valve body, so that the three-way valve can be made smaller and lighter.
It is useful for increasing versatility, reducing noise, and improving economic efficiency.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing an embodiment of a three-way valve according to the present invention;
FIG. 2 is a cross-sectional view showing the operating state of the bear according to the same embodiment, FIG. 3 is a cross-sectional view taken along the line AA in FIG. 1, and FIG. 4 is a cross-sectional view taken along the line B-B in FIG. 2...Introduction port 3.4...Discharge port 5...Valve body 6...Spring 7...Switching means

Claims (1)

[Claims] Three ports communicating with a flow path formed inside the frame, and a fluid flowing in from one of the introduction ports is selectively discharged from one of two discharge ports. A three-way valve having a valve body for switching a flow path in a frame body, and a valve body for switching a flow path in a frame body, wherein the valve body is normally spring-loaded in a direction to close one discharge port and open the other discharge port. and a switching means made of an energized heat-generating shape memory alloy whose one end is fixed to the valve body and the other end is fixed to the frame, and the switching means is energized. A three-way valve characterized in that the valve body is moved against the spring to switch the opening and closing direction of the discharge port.