KR20050021374A - Liquid cooling arrangement for electric machines - Google Patents

Abstract

The cooling apparatus of the electric machine includes a heat storage member provided with a plurality of C-shaped channels and a cooling tube formed to a size so as to be inserted into the plurality of C-shaped channels of the heat storage member. The cooling tube once inserted into the plurality of channels is deformed to fit the plurality of C-shaped channels, thereby providing for the heat stored in the heat storage member to be extracted by the cooling fluid circulating in the cooling tube.

Description

LIQUID COOLING ARRANGEMENT FOR ELECTRIC MACHINES}

The present invention relates to an electric machine. More specifically, the present invention relates to a liquid-cooled apparatus of an electric machine.

Electric machines, such as motors or generators, are well known in the art. In addition, it is well known that electric machines generate heat as a by-product, and this heat must somehow be extracted from the machine in order to improve the performance of the machine and to prevent degradation in the early stages.

In general, electric machines are air-cooled. This air cooling is easily performed by providing an aperture in the body of the machine and forcing air into the opening. Since air is generally an inefficient cooling fluid, the efficiency of such a cooling device is low. In addition, some electric machines operate in environments where such openings cannot be provided in the machine body.

In addition, an electric machine using a cooling fluid is a known technique. For example, European Patent No. 003093, named inventor Nakamura and entitled "Motor Liquid Cooling Apparatus", provides a plurality of openings provided so that the cooling liquid flows in an axial direction when a plurality of laminations are assembled. An electric motor having two laminated plates has been proposed. The drawback of Nakamura's system is the risk of motor failure caused by a short circuit. In practice, the failure cause can occur suddenly by breaking the connection between adjacent laminates.

Thus, electrical machinery still requires cooling device technology.

In the accompanying drawings,

1 is a perspective view and a partially exploded view showing a stator of an electric machine provided with a cooling device according to a first embodiment of the present invention;

2 is a perspective view of a cooling tube inserted into a plurality of channels provided in the stator of FIG.

3 is a perspective view showing that the stator of FIG. 1 is complete;

FIG. 4 is a cross-sectional view illustrating the insertion of a cooling tube into a plurality of channels provided in the stator of FIG.

5A is a cross-sectional view of a cooling tube inserted in a plurality of channels and modified in accordance with a first pattern for permanently installing the cooling tube in the plurality of channels;

Fig. 5B is a cross sectional view showing a cooling tube inserted in a plurality of channels and modified according to a second pattern for permanently installing the cooling tube in the plurality of channels;

6 is an exploded perspective view of a cooling apparatus according to a second embodiment of the present invention.

FIG. 7 is a side view showing deformation of a cooling tube in a plurality of channels of the heat storage member in the cooling device of FIG.

8 is a perspective view and a partially exploded view showing the stator of the cooling device and the electric machine of FIG.

Figure 9 is a side view of the assembled stator including the cooling device of Figure 6;

It is therefore an object of the present invention to provide a liquid-cooled apparatus of an improved electrical machine.

More specifically, the cooling device of the electric machine according to the present invention,

A heat storage member provided with a plurality of C-shaped channels; And

It includes a cooling tube formed in accordance with the standard to be inserted into the plurality of C-shaped channels of the heat storage member,

a) the cooling tube once inserted into the plurality of C-shaped channels is deformed to fit the plurality of C-shaped channels, and b) the heat stored in the heat storage member is provided to be extractable by the cooling tube.

An electric machine according to another aspect of the present invention,

A stator of a cylindrical shape having a substantially hollow;

A rotor rotatably installed on the stator; And

Including a cooling device,

The cooling device

A heat storage member provided with a plurality of C-shaped channels and coupled with the stator to extract heat; And

It includes a cooling tube formed in accordance with the standard to be inserted into the plurality of C-shaped channels of the heat storage member,

a) the cooling tube once inserted into the plurality of channels is deformed to fit the plurality of C-shaped channels, and b) the heat stored in the heat storage member is provided to be extractable by the cooling tube.

Here, the expression "electric machine" is understood not only to be used in such a machine, but also to include both an electric motor and an electric generator.

Other objects, advantages and features of the present invention will become more apparent from the following detailed description of the embodiments described in conjunction with the accompanying drawings.

In short, the first embodiment of the present invention is shown in Figs. 1 to 5b, and uses a plurality of laminates of stators as heat storage members provided with approximately a plurality of C-shaped channels in which cooling tubes are installed. In operation, cooling fluid is circulated in the cooling tube to extract heat stored in the plurality of laminates.

A second embodiment of the present invention is shown in Figures 6-9 and also utilizes a separate heat storage member provided with a plurality of C-shaped channels in which cooling tubes are installed. The heat storage member is inserted into a stator of an electric machine having a cooling tube in contact with both the heat storage member and the stator. In operation, cooling fluid is circulated in the cooling tube to extract heat accumulated in the heat storage member and stator.

1 to 5B, the cooling device 10 according to the first embodiment of the present invention will be described in detail.

1 shows a stator 12 of an electric machine (not shown). The stator 12 consists of a plurality of identical laminations stacked. The stator 12 has a substantially cylindrical shape and includes a plurality of right angled external channels 14 provided in the coil 16. The stator 12 is a so-called internal stator. That is, a rotor (not shown) is installed in the stator 12 so that the stator 12 is coaxial and external.

As will be described later, a plurality of laminates of the stator 12 are used as heat-storing elements.

The inner side of the stator 12 is provided with a plurality of C-shaped channels 20.

The cooling device 10 also comprises a cooling tube 22 having a substantially circular cross section, provided with a suction tube 24 and a discharge tube 26. As shown in Fig. 1, the cooling tube 22 can be folded to have a bent shape.

As will be described in detail below, the cooling tube 22 is formed to a size so as to be inserted into the plurality of C-shaped channels 20 of the stator 12.

2 shows a cooling tube 22 inserted into a plurality of C-shaped channels 20 of the stator 12 approximately. As shown in Fig. 2, the bent portion of the cooling tube 22 may optionally be formed such that its rounded portion extends outward of the singer stator 12. As shown in Fig. 3, since the round portion of the cooling tube 22 is folded outward, this can increase the contact surface between the cooling tube 22 and the stator 12, so this device is important.

4 and 5A show that each C-shaped channel 20 has a substantially closed C-shaped shape. That is, the opening of each C-shaped channel 20 is smaller than the largest width in the channel. The circular cross section of the cooling tube 22 also corresponds to the opening of the C-shaped channel 20 to be inserted into the C-shaped channel.

As shown in Fig. 4, the first step for inserting the cooling tube 22 into the plurality of channels 20 is that of the stator 12 corresponding to the plurality of straight portions of the cooling tube 22. Roughly aligned with channel 20. This operation is facilitated by significantly modifying the bent shape of the tube 22 to be inserted into the central opening of the stator 12.

The next insertion step deforms the curved shape of the cooling tube 22 such that each straight cross section is inserted into a corresponding channel (indicated by arrow 28 in FIG. 4). The result of this step is shown in broken lines in FIG.

In order to keep the plurality of straight portions of the cooling tube 22 in the channel 20, these straight portions are deformed to conform to the C-shaped shape of the plurality of substantially closed channels 20. To achieve this, pressure is radially pressed on the cooling tube 22 (indicated by arrow 30a in FIG. 5A). This radial pressure is applied to tube 22 as indicated by arrow 32. This results in widening of the. According to the first deformation type of the cooling tube 22, the cooling tube 22 once deformed exhibits a slightly convex surface with respect to the inner surface of the stator 12.

Optionally, thermal conductivity and / or adhesive material may be positioned between the channel 20 and the tube 22 to enhance heat transfer between the channel 20 and the tube 22.

In addition, although many materials can be used for the cooling tube 22, good results can be obtained by using copper tubes.

Referring to FIG. 5B, the second variant type of cooling tube 22 inside the plurality of channels 20 will be briefly described. As shown in FIG. 5B, the second variant type of cooling tube 22 exhibits a slightly concave surface with respect to the inner surface of the stator 12. In addition, to achieve this, pressure is radially pressed on the cooling tube 22 (indicated by arrow 30b in FIG. 5B).

This second variant type is important because it prevents unwanted looseness of the cooling tube 22 inside the plurality of channels 20.

6 to 9, the cooling device 100 according to the second embodiment of the present invention will be described in detail.

As mentioned above, the cooling device 100 uses a separate heat storage member 102. As will be described in detail below, the heat storage member 102 includes an outer circumferential channel 104 into which a cooling tube 106 having a curved shape can be inserted. Although not shown in the figure, the channel 104 has a bent shape corresponding to the bent shape of the cooling tube 106.

The cooling tube 106 has a generally bent shape and includes a suction pipe 110 and a discharge pipe 112.

As shown in Figures 7-9, the channel 104 has an approximately open C-shape. That is, the opening of the channel 104 is approximately the same width as the largest portion of the channel.

In addition, the cooling tube 106 inserted into the channel 104 is substantially straight. The cooling tube 106 is first positioned so that the cooling tube 106 properly faces the channel 104. The cooling tube 106 (shown in solid line in FIG. 7) is then inserted into the channel 104. Finally, the cooling tube 106 is deformed so that the cooling tube 106 (shown in broken lines in FIG. 7) does not protrude to the outer surface of the heat storage member 102. This is done by pressurizing the pressure radially inside (indicated by arrow 114), which is applied by force on tube 106 to fit channel 104 (indicated by arrow 116).

As mentioned above, thermal conduction and / or adhesive material may optionally be positioned between channel 104 and tube 106 to enhance heat transfer between channel 104 and tube 106.

As shown in FIG. 8, once the cooling tube 106 is properly inserted into the heat storage member 102, the cooling device 100 may be inserted into a stator 118 of an electrical machine (not shown).

9 is a cross-sectional view of the cooling device 100 installed in the stator 118. As the cooling tube 106 contacts both the heat storage member 102 and the stator 118, one skilled in the art will recognize that heat is extracted from these two elements by the cooling fluid circulating in the cooling tube 106. will be.

Although two embodiments of the present invention are shown as part of an electric machine provided with an internal stator and an external rotor (not shown), those skilled in the art can readily adapt the present invention to use in an electric machine having an external stator and an internal rotor. There will be.

In addition, while embodiments of the present invention have been described above using an open cooling tube in which a flow of fluid is used to extract heat from the heat storage member, other cooling techniques, such as, for example, heat pipes, can be expected. In practice, those skilled in the art will have no problem designing or modifying known heat pipes so that the heat pipes can be installed in a plurality of C-shaped channels. For example, in the first embodiment shown in Figs. 1-5B, a separate straight heat pipe (not shown) can be inserted into each longitudinal channel 20, and the first shown in Figs. In two embodiments, a continuous heat pipe (not shown) may be inserted into the channel 104.

In addition, the two embodiments shown in Figs. 1 to 5B and 6 to 9, respectively, can be combined to improve the cooling efficiency.

The present invention described above is not limited to the above-described embodiment and the accompanying drawings, and various substitutions, modifications, and changes are possible within the scope without departing from the technical spirit of the present invention. It will be apparent to those who have knowledge.

Claims (21)

A heat storage member provided with a plurality of C-shaped channels; And Cooling tube is formed in accordance with the standard to be inserted into the plurality of C-shaped channels of the heat storage member Including; The cooling tube inserted into the plurality of channels is deformed to fit the plurality of C-shaped channels, and heat stored in the heat storage member is extracted by the cooling tube. Cooling system for electric machines. The method of claim 1, Extraction of heat stored in the heat storage member Through the circulation of cooling fluid in the cooling tube Cooling system for electric machines. The method of claim 1, The cooling tube has a circular cross section Cooling system for electric machines. The method of claim 1, The cooling tube is folded to be bent shape Cooling system for electric machines. The method of claim 1, The heat storage member Formed of multiple laminates of stators of electrical machines Cooling system for electric machines. The method of claim 5, The stator has a tubular shape, A plurality of C-shaped channels are provided on the inner surface of the stator Cooling system for electric machines. The method of claim 6, The plurality of channels Parallel to the longitudinal axis direction of the tubular stator Cooling system for electric machines. The method of claim 7, wherein The cooling tube is folded to be bent shape, When the cooling tube is inserted into a plurality of channels of the heat storage member, the cooling tube represents a protruding round that is folded on the heat storage member to maximize the contact surface between the cooling tube and the heat storage member. Cooling system for electric machines. The method of claim 6, The plurality of channels Perpendicular to the longitudinal direction of the tubular stator Cooling system for electric machines. The method of claim 6, The plurality of channels has a closed C shape Cooling system for electric machines. The method of claim 6, The plurality of C-shaped channels and cooling tube When the cooling tube is inserted into a plurality of channels and deformed, the cooling tube is formed to be coplanar with the inner surface of the stator. Cooling system for electric machines. The method of claim 6, The plurality of C-shaped channels and cooling tube When the cooling tube is inserted into a plurality of channels and deformed, the cooling tube is formed to be concave with respect to the inner surface of the stator. Cooling system for electric machines. The method of claim 1, The heat storage member Made of heat storage material and having a cylindrical shape with a hollow having an outer diameter smaller than the inner diameter of a cylindrical stator with a hollow of an electrical machine Cooling system for electric machines. The method of claim 13, The heat storage material comprises aluminum Cooling system for electric machines. The method of claim 13, The plurality of C-type channels Provided on the outer surface of the heat storage material Cooling system for electric machines. The method of claim 15, The plurality of C-shaped channels have an open C-shaped shape Cooling system for electric machines. The method of claim 15, The plurality of C-shaped channels and cooling tubes are sized such that the cooling tubes are coplanar with the inner surface of the stator when the cooling tubes are inserted into and deformed; When the heat storage member is inserted into the stator of the electric machine, the cooling tube provides contact with both the heat storage member and the inner side of the stator of the electric machine. Cooling system for electric machines. A stator of cylindrical shape with a hollow; A rotor rotatably installed on the stator; And Cooling system Including, The cooling device A heat storage member provided with a plurality of C-shaped channels and coupled with the stator to extract heat; And Cooling tube is formed in accordance with the standard to be inserted into the plurality of C-shaped channels of the heat storage member Including; The cooling tube inserted into the plurality of channels is deformed to fit the plurality of C-shaped channels, and the heat stored in the heat storage member is extracted by the cooling tube. Electromechanical. The method of claim 18, Extraction of heat stored in the heat storage member Through the circulation of cooling fluid in the cooling tube Electromechanical. The method of claim 18, The heat storage member is formed of a plurality of laminated plates of the stator; A plurality of C-shaped channels are provided on the inner surface of the stator Electromechanical. The method of claim 18, The heat storage member Made of heat storage material, and having a cylindrical shape having an outer diameter smaller than the inner diameter of the cylindrical stator having the hollow Electromechanical.