JPH0225992Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a temperature-sensitive valve that operates by transmitting a temperature-sensitive element and a valve that operate in response to temperature through a mechanical transmission means, which are located apart from each other.

Conventionally, when detecting temperature and operating an operating mechanism based on the detected temperature, the temperature detection signal is converted into an electrical signal, transmission is performed using electric wire, and the operating part is a valve that uses electromagnetic force. Most of them open and close. The method of detecting temperature and converting the detection signal into an electrical signal is useful when long-distance transmission is required, but it requires a power source for both the temperature detection and actuating device, and it is difficult to use depending on the usage environment. This causes various problems such as electrical insulation properties and fire prevention measures.

In view of these points, the present invention is capable of reversibly opening and closing the valve as the temperature changes, without using a power source for the temperature detection and actuating device. The main objective is to propose a temperature-sensitive valve using a shape memory alloy that can continuously control the degree of opening and closing.

First, the shape memory alloy used in the present invention will be explained. Shape memory alloys have the property of remembering the shape formed by the matrix during the phase transformation of matrix-martensitic transformation that occurs as the temperature rises and falls. Because it has large displacement and deformation force, it is attracting attention as a new temperature-sensitive element.

Shape memory alloys include Ni-Ti alloy, Cu-Al-Ni
There are various alloys such as alloys, Cu-Zn-Al alloys, etc., but in a certain alloy composition range, these alloys undergo martensitic transformation at a temperature near room temperature, and in this alloy composition range, the parent phase at a temperature above martensitic transformation occurs. The formed shape has the characteristic that it deforms below the martensitic transformation temperature and returns to the shape previously formed in the matrix when the temperature is returned to the matrix temperature. The tensile strength for the same amount of strain at a certain time is more than three times that during martensitic transformation. Therefore, by combining it with a mechanical spring, the deformation force of the temperature sensing element made of the shape memory alloy is large when it is in the matrix state, and when the temperature is low and the shape memory alloy is undergoing martensitic transformation, the deformation force of the spring is large. The spring force is strong, and the shape memory alloy can be deformed by the force of the spring. Therefore, it is possible to construct a temperature-sensitive mechanism that repeats expansion and contraction as the temperature rises and falls.

Next, the structure of the present invention will be described. A temperature sensing element includes two or more shape memory alloys having different martensitic transformation temperatures and a heat collecting plate formed in series in the operating direction.
A temperature-sensitive valve comprising a transmission mechanism that mechanically connects a temperature-sensitive element and a valve portion of the valve, and a valve configured such that the valve portion is biased in response to mechanical displacement of the temperature-sensitive element, The valve portion of the valve is provided with a spring that generates a force greater than the deformation force during martensitic transformation of the temperature sensing element and smaller than the deformation force during matrix transformation.

An example of the present invention will be described below with reference to the drawings. FIG. 1 is a plan view showing an example of a temperature-sensitive valve, and FIG. 2 is a side view of the same. A indicates a temperature sensing element, which consists of two types of shape memory alloys 11a and 11b having different martensitic transformation temperatures, a metal body 2 for heat collection connected to both ends of the metal body 2, and a holding part 3 for fixing the temperature sensing element A. It consists of The metal body 22 is made of copper or a copper alloy. In this case, the configuration is such that the displacement length when all the shape memory alloys are deformed is the same as the displacement length of the operating shaft of the valve. That is, as shown in FIG. 2, the shape memory alloy 11a with a low martensitic transformation temperature is deformed sequentially and the connection part with the line C is displaced, and as the temperature of the temperature sensing element A further increases, as shown in FIG. , the shape memory alloy 11b is also deformed.

B indicates a valve, which, when temperature sensing element A generates mechanical displacement in response to temperature, continuously controls the flow rate of fluid or detects an abnormality by mechanical displacement and stops the flow of fluid. This is a valve for
C indicates a line for transmitting the displacement of the temperature sensing element A when the temperature sensing element A responds and is displaced; this line must not be loose and does not need to be a hard rod;
Any wire that does not deform due to mechanical tension may be used.
Furthermore, it is not necessary to draw the lines in a straight line for the purpose of transmitting displacement.
Therefore, when there is no slack in the line C and the temperature sensing element A and the operating valve B move easily due to the displacement of the temperature sensing element A, the distance between the temperature sensing element A and the operating valve B may be several to several tens of meters.

FIG. 3 is a sectional view showing the detailed structure of valve B, and FIG. 4 is a side view of FIG. 3. Reference numeral 5 usually indicates a mechanical spring, which is made to provide a force that balances the deformation pressure of the temperature-sensitive element A due to changes in temperature, and the spring pressure is adjusted by screws 9 and 20. 6 indicates the operating axis, which is the first
As shown in the figure, the temperature sensing element A is connected to the transmission mechanism 4 and moves inside the main body 7 when the temperature sensing element A is displaced due to temperature. A notch 6a is formed in a part of the operating shaft 6,
The fluid entering from the right side in FIG. 3 enters the left chamber through the notch 6a of the operating shaft 6 and flows toward the outlet indicated by the arrow. The other part of the operating shaft 6 serves as a valve portion for the discharge side valve seat of the main body 7.

In FIG. 3, the temperature is low and it is in a state of martensitic transformation as shown in FIG. Therefore, since the pressure of the spring 5 is greater than the biasing force of the shape memory alloy 1, the temperature sensing element A is in an extended state. Now, when the temperature rises and the temperature sensing element A becomes the matrix, the temperature sensing element A returns to the memorized shape, and the deformation force of the temperature sensing element A increases due to the pressure of the spring 5, as shown in Fig. 5. As shown in FIG. 2, the shape memory alloy 1 is deformed and force is transmitted to the actuating valve B via the transmission line C. Therefore, the operating shaft 6 is pulled against the force of the spring 5, and as shown in FIG. 6, the operating shaft 6 closes the outlet 7a and the flow of fluid is interrupted. The pressure of the spring 5 is larger than the pressure when the shape memory alloy is the matrix and the deformation force of the alloy 1 is contracted, and when the temperature of the temperature sensing element A is low and martensitic transformation occurs. The pressure of the spring 5 is configured to be greater than the displacement force of the temperature sensing element A. Therefore, the valve of the present invention can continuously open and close the valve as the temperature of the temperature sensing element A rises and falls, thereby controlling the flow of fluid.

The temperature range that can be controlled by two or more types of temperature sensing elements is determined in advance by the alloy composition, but the spring pressure of the spring 5 can be adjusted to a temperature of around 5°C by adjusting the position of the screws 9 and 20. The width can be adjusted.

In the above description, the transmission line C is used as a method for mechanically transmitting the displacement sensed by the temperature sensing element, but a mechanical transmitting means similar to a release may be used instead. In addition, the degree of tension of the transmission line can be adjusted by providing a mechanism for adjusting the tension using a screw at any position of the transmission means, by checking the degree to which the screw 9 of the operating shaft 10 is lifted from the main body of the operating section. can be done.

Furthermore, in the above example, when the temperature of the temperature sensing element rises and contracts, the spring of the valve is compressed, but by incorporating a lever between the temperature sensing element and the transmission part, the temperature sensing element The system converts the force of contraction when the temperature rises into the force of expansion, uses a release in the transmission part, and configures the valve so that the displacement when the temperature sensing element is activated causes the force to push against the valve, causing the valve to operate. be able to.

As described above, according to the present invention, there is provided a temperature sensing element in which two or more shape memory alloys having different martensitic transformation temperatures and a heat collecting plate are formed in series in the operating direction;
A temperature-sensitive valve comprising a transmission mechanism that mechanically connects a temperature-sensitive element and a valve portion of the valve, and a valve configured such that the valve portion is biased in response to mechanical displacement of the temperature-sensitive element, The valve part of the valve is equipped with a spring that generates a force that is greater than the deformation force during martensitic transformation of the temperature-sensitive element and smaller than the deformation force during matrix transformation, so that the above-mentioned deformation force is applied to areas where the ambient temperature changes over time. By installing a temperature element, the valve can be reversibly opened and closed as the temperature rises and falls without using a power source, and the degree of opening and closing of the valve can be continuously controlled according to temperature changes. It has the effect of obtaining. Therefore, it is useful as a temperature monitoring and protection device in places with poor environmental conditions or places where flammable gas, oil, etc. are used, or in temperature control and temperature abnormality detection of heating and steam equipment.

[Brief explanation of drawings]

Fig. 1 is a plan view showing an example of the present invention, Fig. 2 is a side view, Fig. 3 is a sectional view showing the configuration of the main parts of the valve, Fig. 4 is a side view, and Fig. 5 is a side view of the valve.
FIG. 6 is a cross-sectional view for explaining the operation of the example shown in FIG. 3. 11a, 11b...Shape memory alloy, A...Temperature sensing element, B...Valve, C...Transmission line.

Claims (1)

[Scope of Claim for Utility Model Registration] A temperature sensing element in which two or more shape memory alloys having different martensitic transformation temperatures and a heat collecting plate are formed in series in the operating direction, and between the temperature sensing element and the valve part of the valve. In the temperature-sensitive valve, the temperature-sensitive valve includes a transmission mechanism that mechanically connects the temperature-sensitive element, and a valve configured such that the valve part is biased in accordance with the mechanical displacement of the temperature-sensitive element. A temperature-sensitive valve characterized by being provided with a spring that generates a force greater than the deformation force during martensitic transformation and smaller than the deformation force during matrix transformation.