JPS6039658Y2 - heat pipe - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a heat pipe used as a heat transport means, and particularly to a heat pipe having variable conductance that changes the condensation area by a gas buffering method in response to fluctuations in heat input to the evaporation section.

Conventionally known as this type of variable conductance heat pipe, a large-capacity gas reservoir is connected to the condensing section of a container, and the working fluid vapor in the container and the gas in the gas reservoir are transferred to any position in the condensing section. This method is called a gas buffer method, in which the pressure is balanced at the boundary surface, and the condensation area is changed by shifting the position of the boundary surface in response to changes in the steam pressure due to fluctuations in heat input.

Therefore, according to this, although it is effective against fluctuations in the amount of heat input to the evaporation section, some of the gas in the gas reservoir also enters the container and is affected by the heat of the condensation section. When the temperature changes due to fluctuations in the heat release and heat absorption of the gas, the pressure of the gas also changes, shifting the boundary surface with the equilibrium steam, which changes the condensation area and makes it difficult to maintain a constant temperature of the working liquid steam. The problem is that it makes the system go crazy.

The present invention was developed to solve these problems, and focuses on a shape memory member that has the property of changing its shape substantially reversibly in response to temperature changes. A bellows that has the characteristic of contracting as it rises is installed in the gas reservoir, and changes in the gas pressure in the gas reservoir due to fluctuations in the temperature of the condensing section are absorbed by changing the volume of the gas reservoir by contraction of the bellows, thereby reducing the fluctuation in the temperature of the condensing section. The present invention provides a heat pipe in which the heat pipe does not affect the vapor of the working fluid.

Hereinafter, one embodiment of the present invention will be described in detail with reference to the drawings. In the drawings, reference numeral 1 denotes a closed cylindrical container, a fibrous wick 2 is attached to the inner wall of the container 1, and A working fluid 4 is contained in an internal vapor space 3, and predetermined ranges at both ends of the container 1 serve as an evaporating section 5 and a condensing section 6, respectively, and a heat insulating section 7 between them.

Further, a gas reservoir 8 having a large capacity for filling a non-condensable gas 9 is connected to the condensing part 6 at one end of the container 1,
The gas in the gas reservoir 8 and the vapor of the working fluid in the container 1 are pressure-equilibrium at the boundary surface 10 at an arbitrary position of the condensing section 6, and the hydraulic fluid may also leak to the inner wall of the gas reservoir 8. A wick 2 is attached to return the water to the evaporation section 5.

A gas chamber 12 is further attached to the gas reservoir 8 adjacently via a partition wall 11, and a bellows 14 made of a shape memory member expands and contracts on the gas reservoir side of the hole 13 in the approximate center of the partition wall 11 to change the volume. The bellows 14 and the gas chamber 12 are also filled with non-condensable gas 15.

Shape memory members are Cu-Zn-Al, Cu-3i, C
u-Au-Zn, Cu-Al-Ni, Ti-Ni
It is made by heat-treating alloys such as , martensitic transformation to produce a memory effect, and has the property that its shape changes markedly when the temperature changes, and when the temperature is returned, the shape returns to its original memorized state.

Therefore, according to the present invention, the shape memory member is formed into an accordion-shaped bellows 14 so that the volume changes depending on the temperature, and when the temperature rises, it contracts and reduces the volume.

Since the present invention is configured in this manner, when heat absorption is smoothly performed in the condensing section 6 of the container 1 and the temperature there does not rise, the temperature and pressure of the gas 9 in the gas reservoir 8 are maintained constant. Bellows 14 made of a shape memory member
expands and expands its original shape, which increases its volume, so that the volume of the gas reservoir 8 is reduced.

In this state, when the evaporator 5 is heated and the working fluid is evaporated by a predetermined heat input, the vapor moves through the vapor space 3 in the container 1 to the condenser 6.
The boundary surface 10 is arbitrarily set to balance the pressure of the gas 9 in the gas reservoir 8, and the boundary surface 1 thus set is
A condensation area A is determined at 0, and heat radiation or absorption is performed in this condensation area A in an optimal state.

On the other hand, when the vapor of the working fluid is liquefied in the condensing section 6, the liquid returns to the condensing section 5 by capillary force through the wick 2 on the inner wall of the container 1, and by repeating this continuously, the liquid returns to the evaporating section. The heat is sequentially transported from the condensing section 5 to the condensing section 6.

Next, when the heat input to the evaporator 5 changes, the vapor pressure of the working fluid changes and the position of the boundary surface 10 between the gas reservoir 8 and the gas 9 becomes smoother, thereby causing the heat input to the evaporator 5 to change. The condensing area of the condensing section 6 is automatically adjusted according to fluctuations in the temperature, and variable conductance control is performed to keep the working fluid vapor temperature constant.

Furthermore, if heat absorption in the condensing section 6 is interrupted and the temperature there increases due to heat accumulation, the pressure will increase along with the temperature of the gas 9 in the gas reservoir 8 that is partially contained in the condensing section 6. .

Then, the bellows 14 made of a shape memory member inside the gas reservoir 8 detects this and contracts to increase the volume of the gas reservoir 8, thereby absorbing the increased pressure of the gas 9.

Therefore, the position of the boundary surface 10 is connected without shifting,
A constant control of the steam temperature is maintained because an increase in gas pressure does not cause the boundary surface 10 to shift in a direction that reduces the condensation area, thereby increasing the steam temperature.

In addition, to explain how to assemble the gas reservoir 8, gas chamber 12, bellows 14, etc., first, a container is made from a plate material by deep drawing, and this container is bulged to form the bellows 1.
Make 4.

Next, this bellows 14 is brazed to the partition wall 11 without leakage, and heat-treated to impart shape memory, that is, the bellows 14 is heated below the transformation temperature range (-20 to 0°) while inserting a push rod.
C), the partition wall 11 provided with the bellows 14 thus produced is brazed between the gas reservoir 8 and the gas chamber 12, and a non-metallic material is placed inside the gas reservoir 8 and the gas chamber 12. Fill with condensed gas.

As described above, according to the present invention, even if the endothermic temperature in the condensing section 6 fluctuates, the resulting gas temperature and pressure in the gas reservoir 8 are automatically absorbed to prevent this influence from affecting the vapor of the working fluid. Therefore, the variable conductance property is improved, and it can be applied even under usage conditions where the temperature changes to the extent that the condensing section 6 is formed.

Since the temperature of the gas 9 in the gas reservoir 8 is directly detected by the bellows 14 made by using a shape memory member whose shape changes depending on temperature, and the volume of the gas reservoir is changed, the sensor, volume There is no need for increasing/decreasing means, electrical circuits, etc., and the structure is simple.

[Brief explanation of the drawing]

The drawing is a sectional view showing an embodiment of the heat pipe according to the present invention. 1...Container, 4...Hydraulic fluid, 6.
... Condensing section, 8 ... Gas reservoir, 9,15
...Non-condensable gas, 10...Boundary surface, 1
2... Gas chamber, 14... Bellows.

Claims (1)

[Scope of utility model registration request] A gas reservoir filled with gas is connected to the condensing section of the container, and the vapor of the working fluid in the container and the gas in the gas reservoir are brought into pressure equilibrium at an arbitrary position of the boundary surface of the condensing section, and the heat in the evaporating section is reduced. In a heat pipe with variable conductance that changes the condensation area by shifting the position of the boundary surface in response to fluctuations in input, a shape-memory bellows that shrinks as the temperature rises is installed in the gas chamber from a shape-memory member. 1. A heat pipe, characterized in that the heat pipe is provided in communication with the gas reservoir, and is configured to absorb changes in gas pressure in the gas reservoir due to fluctuations in temperature of the condensing section by a change in volume of the gas reservoir due to the bellows.