JPH0361119B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a gun barrel for a tank or the like, and particularly to a gun barrel equipped with an annular cylindrical heat pipe.

Figure 1 is a schematic diagram of the tank, and Figure 2 is an enlarged view of the gun barrel, where 1 is the tank body and 2 is the gun barrel. In such a structure, the temperature of the upper side of the gun barrel that receives sunlight increases greatly, and the temperature of the lower side that does not receive sunlight increases only slightly.As shown in Figure 3, the difference in thermal expansion causes a long gun barrel There is a drawback that the shooting accuracy deteriorates due to bending (indicated by δ in the figure).

In addition, each time the gun barrel is fired, the inside of the gun barrel receives a gas shock from the combustion of the propellant, and heat is generated due to mechanical friction between the bullet and the bandolier inside the barrel, which causes the gun barrel to reach a high temperature and cause the material to deteriorate. This may affect the lifespan of the gun, or the enlargement of the gun barrel diameter due to thermal expansion may create a gap between the bullet and the cavity, causing combustion gas to leak. In addition, this also induces abrasion of the inner surface of the cavity due to the gas. Since this heat is particularly concentrated at the base and upper part of the gun barrel, it is desirable to promote heat dissipation by equalizing the temperature of the entire gun barrel.

Generally, the amount of heat transferred to the gun barrel is determined by the velocity of the gas inside the gun,
It is said that around 5-8% of the propellant combustion energy is transferred to the gun barrel, a function of density and its flame temperature. However, since the heat transfer time for each shot is extremely short, only a very superficial layer of the inner surface of the barrel cavity is heated within this time. For this reason, during continuous firing, the base temperature (temperature inside the barrel cavity just before the next bullet is fired) rises, and the entire gun barrel becomes overheated, making continuous firing impossible.

The present invention eliminates the above-mentioned drawbacks, eliminates the influence of heat from sunlight, equalizes the temperature of the gun barrel, disperses and cools the heat generated by firing, and has an annular cylindrical heat pipe that is easy to manufacture and inexpensive. The purpose is to provide gun barrels.

According to the present invention, this purpose is to provide an annular cylindrical heat pipe in which an annular groove that causes a capillary phenomenon is formed on both the inner wall of the outer tube and the outer wall of the inner tube, and the space between the two walls is a working steam space. This is achieved by mounting the gun barrel around it.

Embodiments of the present invention are shown below in the longitudinal cross-sectional view of FIG.
The description will be made with reference to the cross-sectional view of FIG. 3 is an annular cylindrical heat pipe having a gun barrel with an annular cylindrical heat pipe, which is a feature of the present invention, in which thin annular grooves 6 and 7 are formed directly on the inner wall of the outer tube 4 and the outer wall of the inner tube 5 so that a capillary phenomenon occurs. The annular cylinder is integrally formed with enough hydraulic fluid 8 to wet both wall surfaces. FIG. 6 shows an embodiment in which a plurality of annular cylindrical heat pipes 3 are attached to the gun barrel 2, and each annular cylindrical heat pipe 3 is
It is attached so as to surround the gun barrel 2. Although the heat pipe 3 can be formed as a single unit, it is preferable to use a plurality of heat pipes from the viewpoint of manufacturing.

In such a configuration, if we consider the case where only sunlight is received, the outer tube 4 receiving sunlight
The working fluid 8 in contact with a part of the inner wall evaporates and carries heat to the outer tube 4 and inner tube 5 sides that are not exposed to sunlight, thereby uniformizing the temperature of the gun barrel. Since an annular groove 6 is provided in the inner wall of the outer tube 4, the working fluid 8 is always present in the evaporation section, and heat is transferred in the height direction. Next, considering the case where combustion energy is generated by firing, the gun barrel 2 generates heat especially at the base of the gun barrel 2 as it fires, causing the hydraulic fluid 8 in contact with the outer wall of the inner tube 5 of the annular cylindrical heat pipe 3 to heat up. It performs evaporation and soaking, and also uses the outer tube 4 as a condensing part to radiate heat.
Since the outer wall of the inner tube 5 is provided with an annular groove 7, the working fluid 8 is always present on the outer periphery of the inner tube 5 as an evaporator, and heat is transferred from this in the radial and axial directions. For this reason, it is necessary to seal the working fluid 8 in an amount sufficient to wet the inner wall of the outer tube 6 and the outer wall of the inner tube 7.

In this way, by repeating the evaporation and condensation cycle of the working fluid, heat is transferred and dispersed, making it possible to equalize and cool the gun barrel at the same time. The contact portion between the gun barrel 2 and the annular cylindrical heat pipe 3 may be in direct contact, but it is more preferable to apply a compound or the like to the contact portion to improve heat conduction.

As the compound, a mixture of silicone grease and alumina powder can be used.

As is clear from the above explanation, in this invention,
It has an annular cylindrical shape with an outer tube and an inner tube, and an annular groove that causes a capillary phenomenon is formed on both the inner wall of the outer tube and the outer wall of the inner tube, and the working vapor of the working fluid flows between the two walls. The spaced heat pipe is attached to surround the gun barrel, resulting in the following effects.

It is possible to eliminate the influence of local heat generation caused by sunlight and achieve uniform heating of the gun barrel.

The effect of local heat generation due to firing heat is also removed by the heat dissipation effect of the heat pipe, making it possible to achieve uniform heating of the gun barrel.

The above allows the gun's shooting accuracy to be significantly improved.

Because the grooves are integrally formed on the inner and outer tubes,
It is easy to manufacture and can be realized at low cost.

[Brief explanation of drawings]

Fig. 1 is a schematic diagram of the tank, Fig. 2 is a cross-sectional view of the gun barrel, Fig. 3 is a side view simulating the state in which the gun barrel is exposed to sunlight and its axis, and Fig. 4 a and b are the invention of the present invention. A vertical sectional view and a cross sectional view showing the annular cylindrical heat pipe of the gun barrel with an annular cylindrical heat pipe according to the fifth embodiment.
The figure is a partially enlarged sectional view of FIG. 4a, and FIG. 6 is a longitudinal sectional view showing one embodiment. 2... Gun barrel, 3... Annular cylindrical heat pipe, 4... Outer tube, 5... Inner tube, 6, 7... Annular groove, 8... Working fluid.

Claims (1)

[Claims] 1. Constructed in an annular cylindrical shape having an outer tube and an inner tube,
An annular groove that causes a capillary phenomenon is formed on both the inner wall of the outer tube and the outer wall of the inner tube, and a heat pipe is attached to surround the gun barrel, with the space between the two walls serving as a working vapor space for the working fluid. A gun barrel with an annular cylindrical heat pipe. 2. A gun barrel with an annular cylindrical heat pipe according to claim 1, characterized in that the gun barrel is composed of a plurality of heat pipes surrounding the gun barrel. 3. A gun barrel with an annular cylindrical heat pipe according to claim 1, characterized in that a compound for improving thermal conductivity is interposed between the heat pipe and the gun barrel. With gun barrel.