JPH09163653A - Hollow motor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a motor which can efficiently dissipate heat and improve the degree of freedom of use mode. SOLUTION: Apertures 8A are formed on both ends of a cylindrical housing 8. A cylinder 4 has a circular section, is inserted in the housing 8, and rotatably fixed by the housing, via a bearing 12. In order to form a three-phase induction motor, a cylinder 14 provided with a cage winding is installed on the outer peripheral surface of the cylinder 4, being in close contact with it. The cylinders 14 and 4 constitute a rotor. Inside the housing 8, many laminated cores 16 are arranged at intervals in the peripheral direction of the cylinder, in such a manner that the cores face the cylinder 14 on which the cage winding is formed and form a specific gap with the surface of the cylinder 14. A winding 20 is formed around each of the laminated cores 16 and forms the three-phase induction winding. The laminated cores 16 and the wingings 20 constitute a rotor.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to an electric motor.

[0002]

2. Description of the Related Art Conventional electric motors generally have a rotor formed around a rotating shaft made of a strong and solid material such as iron.
Around this, a gap is formed between the rotor and the stator, and the stator is arranged. Then, the power generated by the electric motor is transmitted to a device or the like which is to be rotationally driven by attaching a gear or pulley to the rotary shaft, or is used to directly drive a fluid by attaching a blade or the like to the rotary shaft. There is.

[0003]

By the way, when the electric motor rotates, a part of the electric energy is converted into heat energy, so that heat is generated from the electric motor. Therefore, depending on the electric motor and depending on the magnitude of the load, the electric motor may reach a considerably high temperature. And if the motor gets too hot,
The driving force is reduced due to a reduction in magnetic field strength, and further, a thermal load is excessively applied to a material forming the electric motor, which causes a failure or shortens a life.

When a conventional electric motor is used to form, for example, a blower, the blades are attached directly to the rotary shaft of the electric motor as described above and rotated. as a result,
Air is driven by the rotating blade body to generate an air flow. However, in such a blower, since the electric motor is arranged in the center of the blade body, the air flow is obstructed by the electric motor in the center, and as a result, the blowing efficiency is reduced.

Therefore, an object of the present invention is to provide a space in the center for free circulation of fluids, placement and insertion of objects, efficient heat dissipation, and flexibility in the usage of electric motors. Another object of the present invention is to provide a hollow electric motor that has high efficiency and can efficiently flow a fluid.

[0006]

In order to achieve the above object, the present invention supports a cylindrical body having a circular cross section and the cylindrical body so as to be rotatable about a center line parallel to the extending direction of the cylindrical body. Supporting means, a rotor formed with the tubular body as a rotation axis, and a stator of an electric motor arranged outside the rotor with a gap formed between the rotor and the rotor. Is characterized by.

The present invention also includes a first cylindrical body having a circular cross section,
A second cylindrical body having a circular cross section inserted inside the first cylindrical body and the first cylindrical body can be rotated around a center line parallel to the extending direction of the first cylindrical body. Support means for supporting
A stator fixed to the second tubular body outside the second tubular body, and a gap is formed between the stator and the stator to face the stator, and the first tubular body is provided. And a rotor formed to include.

According to the present invention, the stator includes an iron core and a winding attached to the iron core, and the rotor is at least partially formed of a conductive material, and is guided by the rotor and the stator. It is characterized in that an electric motor is formed. The invention is also characterized in that the winding is a three-phase induction winding.

The present invention also includes both the rotor and the stator including an iron core and a winding mounted on the iron core.
A direct current motor is formed by the rotor and the stator. The present invention also includes one of the rotor and the stator, which includes an iron core and a winding attached to the iron core, and the other rotor that does not include the iron core and the winding, or The stator includes a permanent magnet, and a DC motor is formed by the rotor and the stator.

In the hollow electric motor of the present invention, the cylindrical body is supported by the supporting means so as to be rotatable about the center line of the cylindrical body, and the rotor is formed with this cylindrical body as the rotation axis.
The stator is arranged outside the rotor with a gap formed between the stator and the rotor. Therefore, the magnetic force acts between the rotor and the stator to rotate the rotor.

In the hollow motor of the present invention in which the first cylinder rotates, the first cylinder is rotatably supported by the support means about the center line of the first cylinder, and the first cylinder is rotated. A stator is fixed to the outer side of the second cylindrical body inserted inside the body. Further, the rotor is configured to include a first tubular body, which faces the stator with a gap formed between the rotor and the stator. Therefore, when the magnetic force acts between the rotor and the stator, the first cylindrical body forming the rotor rotates around the second cylindrical body.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION Next, embodiments of the present invention will be described. 1 is a perspective view showing a first embodiment of the present invention, FIG.
FIG. 4 is a sectional view of the same half. As shown in FIGS. 1 and 2, the hollow electric motor 2 which is a three-phase induction electric motor includes a rotor 6 formed by including a tubular body 4 forming a rotating shaft, a stator 10 housed in a housing 8, and the like. It is composed by. Openings 8A are provided at both ends of the substantially cylindrical housing 8 having a circular cross section.
And a bearing 12 is formed on the inner surface of the edge of the opening 8A.
Is installed. The tubular body 4 has a circular cross section, is inserted into the inside of the housing 8, and is rotatably supported by the housing 8 via a bearing 12 about a center line O parallel to the extending direction of the tubular body 4. There is.

A cylindrical body 14 is closely attached to the outer peripheral surface of the cylindrical body 4 to form a three-phase induction motor. A large number of grooves parallel to the center line of the cylinder 4 are formed on the outer peripheral surface of the cylinder 14 at regular intervals in the circumferential direction, and aluminum or copper bars (not shown) are fitted in these grooves. A squirrel cage winding is formed. The cylindrical body 4 and the cylindrical body 14 having the cage winding form the rotor of the hollow motor 2.

Inside the housing 8, a large number of laminated cores 16 are formed in the circumferential direction of the cylindrical body 14 so as to face the cylindrical body 14 and form a predetermined gap with the surface of the cylindrical body 14. It has been placed. The ends of the laminated cores 16 on the housing 8 side are connected to each other by a laminated core 18, and the laminated cores 18 are attached and fixed to the inner surface of the housing 8. A winding 20 is wound around each laminated core 16,
It forms a three-phase induction winding. These laminated iron cores 16 and 1
The stator of the hollow motor 2 is formed by 8 and the winding 20. The laminated iron cores 16 and 18 may be formed by punching a plate-shaped material by press working in a state where the respective portions of the laminated iron cores 16 and 18 are integrated, and laminating the laminated iron cores 16 and 18 to form an integrated laminated iron core 16. Of course it is possible. Reference numeral 26 in the figure denotes a flange for mounting and fixing the housing 8.

When a three-phase AC voltage is applied to the winding 20 through the cable 22 to the hollow electric motor 2 thus constructed, the magnetic field generated at the laminated iron core 16 causes the cylindrical body 1 to move.
An electromotive force is induced in 4 to cause a current to flow, and the magnetic force acting between the laminated iron core 16 and the cylindrical body 14 causes the cylindrical body 14 and thus the cylindrical body 4 to be rotationally driven in the direction of arrow A, for example.

The hollow electric motor 2 has a hollow central portion, and air can freely flow in the hollow portion 4A. Therefore, the heat generated by the hollow electric motor 2 is radiated only from the outside of the housing 8. Instead, heat is also radiated from the inner surface side of the cylindrical body 4. Therefore, the heat generated can be removed very efficiently as compared with the conventional electric motor. Therefore, it is possible to prevent a decrease in driving force due to a decrease in magnetic field strength, a failure, or a shortened life.

Further, in the case of constructing a blower using the hollow motor 2, for example, as shown in FIG. 3, inside the tubular body 4, a blade that rotates with the tubular body around the center line of the tubular body 4 is provided. The body 24 may be attached. As a result, when the tubular body 4 rotates in the direction of arrow A, for example, the blade body 24 rotates,
For example, air is flowed and blown in the direction of arrow B (FIG. 1). In such a blower, since there is no electric motor or the like in the central portion of the blade body 24 as in the conventional case and there is no obstruction to the movement of air, it is possible to efficiently blow air.

Even if the hollow electric motor 2 is not used as a blower, if some kind of blade body such as the blade body 24 in FIG. An air flow is generated, more heat is removed from the inside of the cylindrical body 4, and a further heat dissipation effect is obtained.

Next, a second embodiment will be described. FIG.
Is a perspective view of the second embodiment, and FIG. 5 is a half sectional view of the same.
As shown in FIGS. 4 and 5, the hollow motor 32, which is a three-phase induction motor, includes a rotor 36 formed by including a first cylindrical body 34 having a circular cross section and a first cylinder. Body 34
The stator 40 is formed by including a second tubular body 38 having a circular cross section inserted therein. The first tubular body 34 has the bearings 42 at the inner portions of both end portions thereof, so that the first tubular body 34 is different from the second tubular body 38.
Is rotatably supported around a center line O parallel to the extending direction of the. A cylinder 44 is closely attached to the inner surface of the first cylinder 34 to form a three-phase induction motor. A large number of grooves parallel to the extending direction of the first tubular body 34 are formed on the outer peripheral surface of the tubular body 44 at regular intervals in the circumferential direction.
An aluminum rod or a copper rod (not shown) is filled in these grooves to form a cage winding. The rotor of the hollow motor 2 is formed by the first cylinder 34 and the cylinder 44 in which the cage winding is formed.

On the outer peripheral surface of the second tubular body 38, a large number of laminated cores 46 are formed so as to face the tubular body 44 and form a predetermined gap with the inner surface of the tubular body 44. 38 are arranged at regular intervals in the circumferential direction. The ends of the laminated cores 46 on the second cylinder 38 side are connected to each other by a laminated core 48, and the laminated core 48 is attached to and fixed to the outer surface of the second cylinder 38. A winding 50 is wound around each laminated core 46 to form a three-phase induction winding. The hollow electric motor 3 is formed by the laminated cores 46, 48 and the winding wire 50.
Two stators are formed. The laminated cores 46, 4
8 is a laminated core 46, 4 made by pressing a plate-shaped material
Of course, it is also possible to form the laminated cores 46 and 48 by punching and stacking the respective portions of 8 integrally. Reference numeral 56 in the drawing denotes a flange for attaching and fixing the second tubular body 38.

When a three-phase AC voltage is applied to the winding 50 through the cable 52 to the hollow motor 32 thus constructed, an electromotive force is induced in the tubular body 44 by the magnetic field generated at the laminated core 46. Then, a current flows and the magnetic force acting between the laminated iron core 46 and the cylindrical body 44 causes the cylindrical body 4 to move.
4, therefore the first cylindrical body 34 is rotationally driven in the direction of arrow A, for example.

The hollow electric motor 32 has a hollow central portion, and air can freely flow in the hollow portion 38A. Therefore, the heat generated by the hollow electric motor 32 is radiated only from the outside of the rotor 36. In addition, the heat is also radiated from the inner surface side of the second tubular body 38. Therefore, the heat generated can be removed very efficiently as compared with the conventional electric motor. Therefore, it is possible to prevent a decrease in driving force due to a decrease in magnetic field strength, a failure, or a shortened life.

Further, as shown in FIG. 6, if the blade body 54 is attached to the outer periphery of the first cylindrical body 34 forming the rotor 36, an air flow is generated with the rotation of the first cylindrical body 34. As a result, more heat is removed from the outside of the first cylindrical body 34, and a further heat dissipation effect is obtained.

The hollow portion 4 of these hollow electric motors 2 and 32
Not only can air be circulated in A and 38A, but some member can be inserted or arranged. For example,
In the case of the hollow electric motor 32, the supporting member of the hollow electric motor 32 is inserted into the hollow portion 38A, and the second cylindrical body 38 is inserted into the supporting member.
Can be attached to support the hollow motor 32 so as to be movable along the support member. Not limited to this example,
The hollow portions 4A and 38A of the hollow electric motors 2 and 32 can be used in various ways, and the degree of freedom in the usage form of these hollow electric motors 2 and 32 is extremely high.

In the above embodiment, the case of a three-phase induction motor has been described as an example, but of course, the present invention is also effective in the case of a single-phase induction motor and is also effective for a DC motor. is there. In the case of a DC motor, as is conventionally known,
Each of the rotors 6 and 36 and the stators 10 and 40 may be composed of an iron core and a winding wound around the iron core, or one of them may be composed of a permanent magnet. At that time, when the rotor is composed of the iron core and the winding, the current flowing through the winding may be switched by the commutator and the brush according to the rotation angle of the rotor, as in the conventional DC motor. Further, when the rotor is configured by using permanent magnets, the current supplied to the winding of the stator may be switched according to the rotation angle of the rotor by an appropriate control device.

The lengths of the rotor 6 and the stator 10 of the hollow motor 2 are arbitrary. Therefore, for example, the cylindrical body 4,
If the length 14 is shorter than the diameter and the stator 10 is also composed of the laminated iron core 16 or the like having a length corresponding thereto, the thin hollow electric motor 2 can be formed. The same applies to the hollow motor 32. The thin hollow motor 32 can be formed by using, as the first cylindrical bodies 34, 44, 38, those having a length shorter than the diameter.

[0027]

As described above, in the hollow motor of the present invention in which the cylindrical body of the central portion rotates, the cylindrical body is rotatably supported by the supporting means about the center line of the cylindrical body, and the rotor is rotated. Is formed with this cylindrical body as a rotation axis. The stator is arranged outside the rotor with a gap formed between the stator and the rotor. Therefore, the magnetic force acts between the rotor and the stator to rotate the rotor.

Further, in the hollow motor of the present invention in which the first cylindrical body rotates, the first cylindrical body is rotatably supported around the center line of the first cylindrical body by the supporting means. A stator is fixed to the outer side of the second cylindrical body inserted inside the second cylindrical body. Further, the rotor is configured to include a first tubular body, which faces the stator with a gap formed between the rotor and the stator. Therefore, when the magnetic force acts between the rotor and the stator, the first cylindrical body forming the rotor rotates around the second cylindrical body.

Therefore, in these hollow motors of the present invention,
Since the central portion, that is, the inside of the cylinder and the second cylinder is hollow and air can freely flow, heat is radiated not only from the outside of the electric motor but also from the inside surface facing the hollow portion, The heat generated is removed very efficiently. Further, some member can be arranged or inserted inside the cylindrical body or the second cylindrical body, and the degree of freedom in the usage form of the electric motor is high. Furthermore, when a fluid driving means is configured by mounting a blade on the inside of the cylindrical body, there is nothing in the center of rotation of the blade such as an electric motor that hinders the movement of the fluid as in the conventional case. The fluid can be moved very efficiently.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a first embodiment of the present invention.

FIG. 2 is a partial cross-sectional view showing in detail a part of the hollow motor of FIG.

FIG. 3 is a perspective view showing a modified example of the hollow electric motor of FIG.

FIG. 4 is a perspective view showing a second embodiment of the present invention.

5 is a partial cross-sectional view showing in detail a part of the hollow electric motor of FIG.

FIG. 6 is a perspective view showing a modified example of the hollow electric motor of FIG.

[Explanation of symbols]

 2, 32 Hollow motor 4, 14, 44 Cylindrical body 4A, 38A Hollow part 6, 36 Rotor 8 Housing 8A, 38A Opening 10, 40 Stator 12, 42 Bearing 16, 18, 46, 48 Laminated iron core 20, 50 Winding Wire 22, 52 Cable 24, 54 Blade body 34 First cylinder body 38 Second cylinder body

Claims (6)

[Claims] 1. A cylindrical body having a circular cross section, a supporting means for rotatably supporting the cylindrical body around a center line parallel to the extending direction of the cylindrical body, and the cylindrical body as a rotating shaft. And a stator disposed outside the rotor with a gap formed between the rotor and the rotor. 2. A first tubular body having a circular cross section, a second tubular body having a circular cross section inserted inside the first tubular body, the first tubular body, and the first tubular body. Support means for rotatably supporting about a center line parallel to the extending direction of the body, a stator fixed to the second cylinder outside the second cylinder, and the stator And a rotor formed to include a gap between the rotor and the stator, the rotor being opposed to the stator, and the rotor. 3. The stator includes an iron core and a winding attached to the iron core, the rotor is at least partially formed of a conductive material, and the rotor and the stator form an induction motor. The hollow electric motor according to claim 1 or 2, which is provided. 4. The winding is a three-phase induction winding.
Hollow electric motor as described. 5. The rotor and the stator both include an iron core and a winding attached to the iron core, and a DC motor is formed by the rotor and the stator. Hollow electric motor as described. 6. One of the rotor and the stator includes an iron core and a winding attached to the iron core,
The hollow according to claim 1 or 2, wherein the other rotor or stator that does not include the iron core and the winding includes a permanent magnet, and a DC motor is formed by the rotor and the stator. Electric motor.