JPH0198788A - Passage closing gear - Google Patents

Abstract

PURPOSE:To reduce costs and frequency in a breakdown and simplify a mechanism by reducing the number of parts by opening and closing a fluid passage by only a thermosensitive operation element made of shape memory alloy or shape memory resin. CONSTITUTION:A thermosensitive operation element 1, whose cross section is nearly U shaped, for example, made of shape memory alloy or shape memory resin is arranged on the outer periphery of a passage 3. Which is made of an elastic pipe-like member 2, for pressure fluid. When the temperature of pressure fluid becomes higher than specified temperature, the thermosensitive operation element 1 shrinks to compress the elastic pipe-like member 2 for shutting-off the passage for fluid at this portion. When it becomes lower than the specified temperature, the thermosensitive operation element 1 expands to open the passage 3.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention uses a shape memory alloy or shape memory resin as a temperature-responsive element and utilizes its thermal deformation to open and close a flow path, thereby allowing air flow from a fluid piping system to a temperature below a predetermined temperature. The present invention relates to a channel opening/closing device that automatically discharges fluid. Discharges condensate from heating radiators, discharges low-temperature water from trace pipes that keep oil pipes warm with steam or hot water, and discharges water below a specified temperature to prevent equipment that uses steam or hot water from freezing. Used when doing something.

2. Description of the Related Art A temperature-responsive valve as an example of a conventional flow path opening/closing device using a shape memory alloy will be described with reference to FIGS. 4 to 6.

The casing parts 71, 72 form fluid passages 73, 74 and a valve chamber 75. The valve chamber 75 is connected to the fluid passage 73 through a through hole 77 formed in a guide wall 76 of the casing member 71 and a valve lower 9 of a valve seat member 78 screwed to the casing member 72.
．． It is connected to 74. A valve body 80 is disposed within the valve chamber 75 facing the valve lower 9. A valve rod 82 is integrally formed on the valve body 80 via a collar portion 81 and guided by a guide wall 76.

A temperature-responsive element 83 made of a shape memory alloy and formed into a coil is disposed between the guide wall 76 and the collar portion 81.

A coiled bias spring 84 is disposed between the valve seat member 78 and the collar portion 81.

As shown in FIG. 6, the temperature-responsive element 83 undergoes thermoelastic martensitic transformation from an austenite phase to a full tensile phase 1 to phase when cooled to a predetermined temperature or lower, and undergoes the reverse transformation when heated to a predetermined temperature or higher. .

It is made to elongate in the austenite phase and contract in the martensite phase.

Bias spring 84 (J As shown in Figure 5, the load and displacement are in direct proportion. Figure 4 shows that when the temperature of the fluid to be controlled is low, the temperature responsive element 83 contracts and the force of the bias spring 84 causes the valve to close. The state in which the body 80 opens the valve lower 9 is shown.

When the temperature of the controlled fluid increases from this state, the temperature responsive element 83 expands against the force of the bias spring 84, and the valve body 80 closes the valve lower 9. When the temperature of the fluid to be controlled becomes low again, the temperature responsive element 83 contracts and enters the state shown in FIG. 4.

Problems to be Solved by the Invention The above-mentioned conventional temperature-responsive valve operates the valve body 80 by utilizing the displacement force of the coiled shape-memory alloy temperature-responsive rope 83 that occurs as the temperature of the fluid to be controlled changes. The flange portion 81 receives the displacement force of the temperature-responsive element 83, and the valve stem 82 and guide wall 76 guide the sliding movement of the valve body 80.
, bias spring 84, etc., the number of parts increases and the structure becomes complicated, leading to problems such as increased costs and increased failure frequency.

The technical object of the present invention is to solve the above problems by minimizing the number of parts and simplifying the structure.

Means for Solving the Problems The technical means of the present invention to solve the above-mentioned technical problems is to form the fluid contact part of the pressure fluid into a pipe shape using an elastic member such as synthetic resin or rubber. A temperature-responsive element made of a shape-memory alloy or shape-memory resin that undergoes reversible transformation in response to temperature changes is disposed around the entire or partial outer periphery of the elastic member, and the pressure fluid passage is opened and closed by expansion and contraction of the temperature-responsive element. This is how it was done.

action The operation of the above technical means is as follows.

A temperature-responsive element made of a shape-memory alloy or shape-memory resin is heated and cooled via the elastic member by a pressure fluid flowing within the elastic member, and reversibly transforms and expands and contracts in response to temperature changes. By opening and closing the pipe-shaped elastic member due to this expansion and contraction action, the fluid passage is opened or closed, and fluid at a temperature below a predetermined temperature is discharged into the automatic fishing rod.

Effect of the invention The present invention produces the following unique effects.

By opening and closing the fluid passage only with a temperature-responsive element made of shape-memory alloy or shape-memory resin, there is no need for a separate valve body, valve port, bias spring, etc., and the number of parts is reduced compared to conventional temperature-responsive valves. In addition, the structure can be simplified, and costs can be reduced and failure frequency can be reduced.

Further, since the fluid contact portion is formed of an elastic member such as synthetic resin or rubber, it is possible to ensure sealing performance when the flow path is closed.

Example An example showing a specific example of the above technical means will be described.

(Example 1: See Figure 1) A pressure fluid passage 3 is formed by a pipe-shaped elastic member 2.

A rod-shaped or flat-shaped temperature-responsive element made of shape memory alloy or shape memory resin is disposed around the outer periphery of the elastic member 2. The temperature-responsive rope has a substantially U-shaped cross section, and is held with an elastic member 2 sandwiched between the U-shaped inner peripheral portion. The heat of the pressure fluid flowing within the elastic member 2 is conducted within the elastic member 2 and transferred to the temperature responsive element 1 . This heat transfer also occurs in the opposite direction.

When the temperature of the pressure fluid reaches a predetermined temperature or higher, the temperature-responsive rope 1 contracts to compress the pipe-shaped elastic member 2 and close the pressure fluid passage 3 (see FIG. 1(b)). When the temperature of the pressure fluid falls below a predetermined temperature, the temperature-responsive element 1 expands and restores its pipe shape to the passage 3 due to the fluid pressure.
(See Figure 1(a)).

(Second embodiment: see FIG. 2) An elastic member 6 such as rubber or synthetic resin is inserted or coated into the inner periphery of the pipe-shaped temperature-responsive element 5 made of shape memory alloy or shape memory resin, that is, the fluid contact part. and set it up. When the temperature of the pressure fluid reaches a predetermined temperature or higher, the temperature-responsive element 5 contracts, and the elastic member 6 on the inner circumference also contracts at the same time, closing the pressure fluid passage 7 (second
(See figure (b)). When the temperature of the pressure fluid falls below a predetermined temperature, the temperature-responsive element 5 expands and restores its original pipe-like shape due to the fluid pressure, opening the passage 7 (see FIG. 2).
a)).

(Third Embodiment: See FIG. 3) A pressure fluid passage 13 is formed by a pipe-shaped elastic member 11. A flat temperature-responsive element 10 made of a shape memory alloy or shape memory resin is arranged on the top of the elastic member 11. When the flat temperature responsive element 10 reaches a predetermined temperature or higher, it bends in a dogleg shape from approximately the center and connects the elastic member 11 to the passage 1.
The pressure fluid passage 13 is closed by pushing it toward the center of the three axes and abutting the convex valve seat 12 provided integrally with the elastic member 11 (see FIG. 3(b)). When the temperature drops below a predetermined temperature, the temperature-responsive element 10 restores its flat shape and opens the passage 13 due to fluid pressure (see FIG. 3(a)).

The shape memory alloy or shape memory resin shall be appropriately selected from conventionally known ones depending on the application and usage conditions.

In this way, by opening and closing the pressure fluid passage 3.7.13 by the expansion and contraction of the temperature responsive elements 1, 5.10, fluid below a predetermined temperature can be automatically discharged with a minimum number of parts and a simple structure. However, it is possible to reliably close fluids with a temperature above a predetermined temperature.

[Brief explanation of the drawing]

1 to 3 are sectional views of a channel opening/closing device according to an embodiment of the present invention, and FIGS. 1 to 3 (a) are sectional views showing a state in which the channel is opened; Figure 3 (b)
) is a sectional view showing a state in which the flow path is closed, FIG. 4 is a sectional view of a temperature-responsive valve as an example of a conventional flow path opening/closing device, and FIG. 5 is a view showing the characteristics of the bias spring shown in FIG. 4. , FIG. 6 is a diagram showing the characteristics of the temperature-responsive element shown in FIG. 4. 1.5, 10: Temperature responsive element 2.6.1 and elastic member 3.7.13: Pressure fluid passage

Claims (1)

[Claims] 1. The fluid contact part of the pressure fluid is formed into a pipe shape using an elastic member such as synthetic resin or rubber, and the entire or partial outer periphery of the elastic member is made of a shape memory alloy or shape memory resin that undergoes reversible transformation in response to temperature changes. A flow path opening/closing device in which the temperature-responsive elements created are arranged and the pressure fluid passage is opened and closed by the expansion and contraction of the temperature-responsive elements.