JP2589586Y2 - Rotary heat pipe - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotary heat pipe used for various kinds of rotating shafts, for discharging or taking in heat through the rotating shaft to efficiently cool or heat. .

[0002]

2. Description of the Related Art One of the uses of a rotary heat pipe is a rotating shaft of a motor. This is to provide a heat pipe function to the rotating shaft of the motor, thereby releasing the heat generated from the rotor of the motor to the outside through the rotating shaft, which is a heat pipe, to prevent overheating. In particular, in a quiet type motor or the like whose outside is sealed with sound insulating material for soundproofing, heat is easily trapped in the motor case, so it is important how to cool it. 2. Description of the Related Art A method using a rotary heat pipe as a rotating shaft of a motor has been conventionally used.

A conventional rotary heat pipe used in a motor has a cylindrical metal container filled with a working fluid as a rotating shaft, and a rotor is attached to an outer periphery of an evaporating portion. The opposite side extends to the outside of the motor to form a condensing portion, and radiation fins are attached to the outer periphery thereof. Therefore, during the operation of the motor, the heat generated by the rotor heats the evaporator of the rotary heat pipe, which is the rotating shaft. On the other hand, the working fluid sealed inside the rotating rotary shaft forms a liquid pool in the lower portion inside the cylinder, and is dispersed in a liquid film form on the inner peripheral surface with the rotation of the rotary shaft.
The liquid film is heated and evaporates, becomes a vapor of the working fluid, and moves to the condensing section. Then, the vapor of the working fluid is deprived of heat in the condensing portion provided with the radiation fins, condensed, returns to the working fluid in a liquid phase, condenses on the inner peripheral surface of the rotating cylinder, and spreads in a liquid film form. Then, the working fluid that has returned to the liquid phase flows due to the positive pressure due to the difference in the thickness of the liquid film, and the working fluid is recirculated. That is, the working fluid in the liquid phase moves from the condensing portion side where the liquid film is thick to the evaporating portion side where the liquid film is thin. Then, it spreads again in the form of a liquid film on the inner peripheral surface of the evaporator, and is repeatedly heated, evaporated, moved to the condenser, and condensed, releasing the heat of the rotor out of the case and cooling. To prevent motor overheating.

[0004]

However, in the above-described motor using a conventional rotary heat pipe as a rotating shaft, the working fluid is supplied to the evaporating section by a difference in thickness of a liquid film formed on the inner peripheral surface of the cylinder. Although the method of refluxing is employed, there is a limit to the amount of the working fluid that can be refluxed to the evaporating section only by the flow caused by the positive pressure generated by the thickness of the liquid film, and thus there is also a limit to improving the heat transport capacity.

The present invention has been made in view of the above circumstances, and has as its object to provide a rotary heat pipe having an excellent heat transport ability.

[0006]

According to the present invention, there is provided a rotary heat pipe in which a condensable working fluid is sealed in a cylindrical rotary shaft. A cross-sectional shape that opens into the inner wall surface of the inside and gradually expands from the opening to the bottom
Shape and a number of grooves continuous in the longitudinal direction
Formed and communicate with each of those grooves
Connecting groove oriented in the circumferential direction of the cylindrical rotary shaft
Is provided .

[0007]

[Function] The cylindrical rotary shaft, which is a rotary heat pipe,
Open to the inner wall surface and from the opening to the bottom
Grooves having a gradually expanding cross-sectional shape and being continuous in the longitudinal direction are formed. Therefore, when this rotating shaft is used for cooling or heating, the effective area of the evaporating section is greatly increased, and a large amount of working fluid can be held in the groove . As mentioned above,
Each group through a connecting groove formed in the direction
The tubes are in communication with each other,
With the rotation, the groove is made to the neighboring groove.
A fluid is supplied. As a result, many grooves
The moving fluid is kept uniform . The working fluid held in each groove is heated from the entire inner surface of the groove and boils vigorously. At this time, since each groove has a shape in which the opening portion is narrow and the inside is widened, the boiling working fluid becomes a vapor bubble in the working fluid in the groove, and when the opening of the groove is narrow, Bumps. As a result, the pressure in the groove is rapidly reduced, so that the liquid-phase working fluid around the groove is sucked into the groove, and the liquid is supplied to the evaporator. In addition, the vapor of the working fluid ejected from the groove moves to the low-temperature, low-pressure condensing part, releases a large amount of heat transported in the form of latent heat of evaporation from the evaporating part, and condenses to become a liquid-phase working fluid. Return to the evaporator again. As a result, it is possible to efficiently cool the evaporator or heat the condenser.

[0008]

FIG. 1 shows an embodiment in which the rotary heat pipe of the present invention is applied to a rotating shaft of a motor as a cooling means.
This will be described with reference to FIG.

The rotary shaft 1 of the motor has a function of a rotary heat pipe. The inner peripheral surface of the rotary shaft 1 is formed in a slit shape having a wide groove and a narrow opening 2a. A plurality of grooves 2 having a size (diameter) that does not generate capillary pressure are continuously formed in the longitudinal direction . Sand
That is, each groove 2 gradually expands from the opening to the bottom.
It has a sharp cross section. Its to the inner the bottom of the rotary shaft 1, the groove 2 is formed on the peripheral surface, puddle of condensable working fluid 3 is sealed is formed. Further, communication grooves 4 are formed at predetermined intervals on the inner peripheral surface of the rotating shaft 1 so as to be substantially orthogonal to the respective grooves 2, so that the working fluid supplied in the axial direction by the respective grooves 2 is formed. The amount is made uniform, and the variation in the amount of working fluid held in each groove 2 is eliminated . That is, this chain
The connection groove 4 is formed so as to communicate with each groove 2. Although not shown, a rotor is formed on the outer periphery of the evaporator on one end of the rotating shaft 1, and the condensing unit on the other end extends outside the casing of the motor, and has radiation fins on the outer periphery. It is provided and can be cooled . The times
The turning shaft 1 is arranged horizontally.

Next, the operation of this embodiment configured as described above will be described. When the motor is operated, the cylindrical rotary shaft 1 rotates integrally with the rotor in the direction of the arrow. Each glue
A liquid reservoir formed at the bottom of the rotary shaft 1 in FIG.
Movement when passing through the inner, its space portion working fluid 3 is filled, the direction of the arrow while holding the working fluid 3 therein
I do. As described above, since the communication groove 4 is formed so as to be orthogonal to each groove 2, the working fluid 3 in the groove 2 is formed.
Is a groove adjacent to the lower side in FIG.
2 is supplied. As a result, the amount of the working fluid 3 in each groove 2 is made uniform.

When the motor is continuously operated and the rotor generates heat, the heat is transmitted to the cylindrical rotary shaft 1 having a heat pipe function. The rotating shaft 1 to which heat has been transferred is heated at an evaporating portion at one end, and the working fluid 3 held in each of a plurality of grooves 2 formed on the inner periphery thereof is heated and boiled. Vapor bubbles are generated. At this time,
Since the working fluid 3 in the groove 2 is heated from the entire inner peripheral surface of the groove 2, the working fluid 3 boils vigorously and generates a large amount of vapor bubbles. However, since the opening 2a of each groove 2 is formed in a narrow slit shape, the steam 3a of the working fluid 3 generated inside is in a bumping state and is ejected from the opening 2a into the space inside the rotary shaft 1. I do. As a result, the inside of the groove 2 is rapidly decompressed, so that the liquid-phase working fluid 3 around the groove 2 is sucked into the groove 2 and passes through each groove 2 in the axial direction, that is, from the condensing portion. The liquid is moved toward the evaporating section.

The steam 3a of the working fluid 3 ejected from the inside of the groove 2 moves to the low-temperature and low-pressure condensing part through the space in the center, and removes a large amount of heat transported from the evaporating part in the form of latent heat of evaporation. The condensed and deprived heat is released into the air from the radiation fins, while the working fluid 3 condensed and returned to the liquid phase returns to the evaporator. Therefore, the heat generated by the rotor is exhausted to the outside of the casing via the rotating shaft 1, and
Motor cooling is performed.

As described above, in this embodiment, since the communication grooves 4 are formed in the direction orthogonal to the large number of grooves 2 formed on the inner circumference of the rotating shaft of the motor, the amount of the working fluid 3 in each groove 2 is increased. Can be equalized, and a stable heat transport ability can be obtained.

In this embodiment, the case where the rotary heat pipe is used for cooling the motor has been described. However, the rotary heat pipe can be used for heating.

[0015]

[Effects of the Invention] As described above, this invention has an opening
The cross section gradually expands from the bottom to the bottom, and the rotation axis
The inner wall has a number of grooves continuous in the longitudinal direction
And the circumference of the rotating shaft so that it can communicate with each groove.
It has a connection groove directed in the direction, and has a structure in which the effective area of the evaporator is enlarged and a large amount of working fluid is easily held on the inner peripheral surface. Therefore, the amount of evaporation of the working fluid is increased, and the heat transport capability is improved.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a rotating shaft according to an embodiment of the present invention.

FIG. 2 is a partially enlarged view of FIG.

FIG. 3 is a sectional front view of a rotating shaft.

[Explanation of symbols]

1 ... rotary axis, 2 ... groove, 2a ... opening, 3 ...
Working fluid, 4 ... communication groove.

Continuing on the front page (72) Inventor Yuji Saito 1-5-1, Kiba, Koto-ku, Tokyo Inside Fujikura Co., Ltd. (72) Inventor Fumiaki Aoyama 1-5-1, Kiba, Koto-ku Tokyo, Japan References JP-A-58-35389 (JP, A) JP-A-58-19691 (JP, A) JP-A-1-203894 (JP, A) JP-B-58-40119 (JP, B2) (58) Field surveyed (Int.Cl. ⁶ , DB name) F28D 15/02

Claims (1)

(57) [Scope of request for utility model registration] 1. A rotary heat pipe in which a condensable working fluid is sealed in a cylindrical rotating shaft, wherein the cylindrical rotating shaft has an opening on an inner wall surface and an opening from the opening to the bottom. Cross section gradually expanded toward
A number of grooves having a shape and continuous in the longitudinal direction
Are formed, and further communicate with the respective grooves.
So that the connection of the cylindrical rotary shaft is oriented in the circumferential direction
A rotary heat pipe having a groove .