JP7320875B2 - Coreless motor and generator - Google Patents

Description

With regard to electric motors, the usage limit that is guaranteed against the temperature rise of coils, magnets, etc. that constitute the electric motor during normal operation is generally indicated as a rating by the manufacturer. Ratings are independent standards guaranteed by the manufacturer when an electric motor is operated at a given voltage and rated torque or rated output, and are generally listed in catalogs and specification tables. For example, the maximum output generated by an electric motor while exhibiting good characteristics at a specified voltage is the rated output, the rotation speed when operating at the rated output is the rated rotation speed, the torque at that time is the rated torque, and the torque at that time is the rated torque. current is displayed as the rated current.

As an electric motor provided on the market by the applicant of the present application, a cylindrical coil is arranged concentrically with respect to the central axis of rotation in a housing, the end face on one side is supported by a stator, and the coil extends in the direction in which the central axis of rotation extends. and a rotor arranged concentrically with respect to the central axis of rotation in a housing and rotating in the circumferential direction of the central axis of rotation.

The rating of this coreless motor is as follows: rated torque T0 = 0.28 Nm, rated current I0 = 9.7 Arms, rated rotational speed n0 = 6537 rpm, rated output P0, under the condition that the temperature of the cylindrical coil does not exceed the allowable upper limit temperature of 130 ° C. = 191.67W.

When this coreless motor was used to drive under conditions exceeding the rating, it was found that the allowable upper limit temperature of the cylindrical coil exceeded 130° C. in just several tens of seconds after the start of driving. The worst case that can be easily assumed from this is that if the motor is driven under conditions exceeding the rating, the cylindrical coil will burn out and be destroyed. Moreover, even if the coreless motor does not break down, it cannot be expected to operate normally for a long period of time from the standpoint of performance.

In this way, although the electric motor may momentarily exceed the rated current at the time of start-up, it is not assumed that the electric motor will normally be continuously operated in a state exceeding the rated current. If the electric motor is overloaded, that is, if it is continuously operated above the rated current, the electric motor coil will generate more heat than expected due to the current.

Therefore, the inventors of the present application provide a cooling mechanism in a coreless motor equipped with a cylindrical coil to prevent the performance deterioration of the electric motor due to heat generation of the cylindrical coil and heating of the magnet, and to prevent the electric motor from exceeding the rating. Proposals have been made to enable operation under load (Patent Documents 1 and 2).

Various proposals have been made to add a cooling function to an electric motor (for example, Patent Documents 3, 4, 5, and 6).

Japanese Patent No. 5943333 Japanese Patent No. 6399721 JP-A-4-359653 JP 2018-157645 A JP 2014-90553 A United States Patent Application Publication US2014/0175917

SUMMARY OF THE INVENTION An object of the present invention is to provide a coreless motor and a power generator that have a simple structure, suppress overheating of coils during operation, and are capable of high output.

In particular, a rotation center axis, a cylindrical coil arranged concentrically with respect to the rotation center axis and extending in a direction in which the rotation center axis extends, and a cylindrical coil arranged concentrically with respect to the rotation center axis, the cylindrical coil It consists of a cylindrical inner yoke and an outer yoke that sandwich a shaped coil in the radial direction between them, and magnets are provided on the outer surface of the inner yoke or the inner surface of the outer yoke, and the magnets are arranged in the circumferential direction of the rotation center axis. An object of the present invention is to provide a coreless motor and a generator capable of suppressing overheating of coils during operation and capable of producing high output in a coreless motor and a generator having a configuration including a rotating rotor.

A rotation center shaft extending axially in the center of a closed housing, and a rotation center shaft disposed concentrically with respect to the rotation center shaft in the housing and having one end face supported by a stator for the rotation. A cylindrical coil extending in the direction in which the central axis extends, and a cylindrical inner yoke that is arranged in the housing concentrically with respect to the rotation central axis and radially sandwiches the cylindrical coil between them. and a cylindrical outer yoke, and a rotor having magnets on the outer surface of the inner yoke or the inner surface of the outer yoke and rotating in the circumferential direction of the rotation center axis. and a generator.

A liquid refrigerant is accommodated in the housing, and the liquid surface of the liquid refrigerant extending in the axial direction in a stationary state is in contact with the outer peripheral surface of the outer yoke. The rotation of the rotor causes the liquid coolant to flow within the housing and contact the cylindrical coil.

Cylindrical coil heats up by causing liquid refrigerant to flow into a donut-shaped space in cross section formed between an inner yoke and an outer yoke that sandwich the cylindrical coil in the radial direction, due to the rotation of the rotor. A liquid refrigerant is brought into contact with the cylindrical coil to take heat from the cylindrical coil, transfer the taken heat to the housing by the liquid refrigerant flowing in the housing, and radiate the heat from the entire outer peripheral surface of the housing having a larger surface area than the cylindrical coil.

As a result, the cylindrical coil that is generating heat due to the operation of rotating the rotor is cooled by the liquid coolant, and the liquid coolant that takes heat from the cylindrical coil that is generating heat flows through the housing. Heat is transferred to the housing and dissipated from the entire outer surface of the housing. As a result, overheating of the coils during operation of the coreless motor is suppressed, and an excessive current is supplied to the coils to enable the coreless motor to output a high rotational speed.

Further, the liquid refrigerant is caused to flow at high speed within the housing by the rotor rotating at high speed within the housing, thereby miniaturizing the liquid refrigerant into fine particles. As a result, the liquid refrigerant in the atomized state flows at high speed inside the housing. Further, part of the flowing liquid refrigerant is vaporized by contacting the heating coil. By these means, the atmosphere inside the housing is mixed with gas and liquid. Since the atmosphere inside the housing is in a gas-liquid mixed state in which the liquid refrigerant in a spray state exists, the heat conduction from the coil that generates heat due to the energization to the housing is improved. As a result, the temperature of the housing is efficiently raised to the same temperature as the heat-generating coil, and the heat is dissipated from the entire outer surface of the housing. As a result, overheating of the coils during operation of the coreless motor is suppressed, and an excessive current is supplied to the coils to enable the coreless motor to output a high rotational speed.

[1]
a central axis of rotation extending axially through the center of the housing to be sealed;
a cylindrical coil arranged in the housing concentrically with respect to the central axis of rotation, having one end face supported by a stator and extending in the direction in which the central axis of rotation extends;
Cylindrical inner rotors arranged in the housing concentrically with respect to the central axis of rotation and rotating in the circumferential direction of the central axis of rotation and sandwiching the cylindrical coils in the radial direction. a rotor comprising a yoke and a cylindrical outer yoke, and having magnets on the outer surface of the inner yoke or the inner surface of the outer yoke;
a liquid refrigerant contained in the housing, the liquid surface extending in the axial direction in a stationary state being in contact with the outer peripheral surface of the outer yoke,
A coreless motor, wherein rotation of the rotor causes the liquid refrigerant to flow within the housing and contact the cylindrical coil.

[2]
The coreless motor according to [1], wherein the outer yoke has a hole radially penetrating the outer yoke.

[3]
a central axis of rotation extending axially through the center of the housing to be sealed;
a cylindrical coil arranged in the housing concentrically with respect to the central axis of rotation, having one end face supported by a stator and extending in the direction in which the central axis of rotation extends;
Cylindrical inner rotors arranged in the housing concentrically with respect to the central axis of rotation and rotating in the circumferential direction of the central axis of rotation and sandwiching the cylindrical coils in the radial direction. a rotor comprising a yoke and a cylindrical outer yoke, and having magnets on the outer surface of the inner yoke or the inner surface of the outer yoke;
a speed reducer comprising a planetary gear mechanism disposed in the housing for transmitting the rotational motion of the rotor about the central axis of rotation to the rotational motion of a rotational motion output section;
a liquid refrigerant contained in the housing, the liquid surface extending in the axial direction in a stationary state being in contact with the outer peripheral surface of the outer yoke,
A coreless motor, wherein rotation of the rotor causes the liquid refrigerant to flow within the housing and contact the cylindrical coil.

[4]
The speed reducer is housed in a cylindrical gear case extending in the direction in which the central axis of rotation extends, and the gear case has a hole radially penetrating the gear case [3]. coreless motor.

[5]
The liquid surface of the liquid refrigerant in the stationary state, which extends in the axial direction, is in contact with the outermost peripheral edge in the radial direction of the planetary gear mechanism.
The coreless motor of [3] or [4].

[6]
A generator equipped with the coreless motor configuration and structure of [1] to [5] above

According to the present invention, it is possible to provide a coreless motor with a simple structure that suppresses overheating of the coils during operation of the motor, and that supplies an excessive current to the coils to allow the electric motor to output a high rotational speed. . Also, a generator having such a structure can be provided.

FIG. 2 is an enlarged cross-sectional view, partly omitted, illustrating the internal structure of a coreless motor according to an embodiment of the present invention; FIG. 2 is an enlarged cross-sectional view, partly omitted, for explaining the internal structure of another embodiment of the coreless motor of the embodiment shown in FIG. 1; FIG. 2 is a conceptual diagram illustrating another embodiment of a liquid refrigerant stirring means in another embodiment of the coreless motor of the embodiment shown in FIG. 1; FIG. 4 is an enlarged cross-sectional view, partly omitted, for explaining the internal structure of a coreless motor according to another embodiment of the present invention; FIG. 5 is an enlarged cross-sectional view, partly omitted, for explaining the internal structure of another embodiment of the coreless motor of the embodiment shown in FIG. 4 ; FIG. 5 is a side view of a cylindrical gear case employed in the embodiment shown in FIG. 5; FIG. 5 is a perspective view of a cylindrical gear case employed in the embodiment shown in FIG. 5; FIG. 5 is a perspective view of another embodiment of the coreless motor of the embodiment shown in FIG. 4; FIG. 9 is a partially cutaway perspective view illustrating the internal structure of the coreless motor shown in FIG. 8 ; FIG. 9 is a partially omitted sectional view for explaining the internal structure of the coreless motor shown in FIG. 8 ; (a) is a partially omitted cross-sectional view for explaining the level of the liquid level of the liquid refrigerant contained in the housing in the stationary state in the embodiment shown in FIGS. 1 and 2; FIG. 11B is a partly omitted cross-sectional view for explaining a case where the height position of the liquid level in the stationary state of the liquid refrigerant is higher than in the case shown in FIG. 11A. FIG. 5 is a partially omitted cross-sectional view for explaining an example of the height position of the liquid level of the liquid refrigerant contained in the housing in the stationary state in the embodiment shown in FIG. 4 ;

(Embodiment 1)
A coreless motor 1 shown in FIG. 1 includes a closed housing 4 and a rotation center shaft 5 extending in the center of the housing 4 in the axial direction (horizontal direction in FIG. 1).

In the embodiment shown in FIG. 1 , the rotation center shaft 5 is rotatably supported by the housing 4 , and the rotation center shaft 5 is the rotary motion output portion of the coreless motor 1 .

In the illustrated embodiment, the sealed housing 4 is composed of a cylindrical casing 2 and a disk-shaped lid 3 that closes the right end opening of the cylindrical casing 2 in FIG. .

The cylindrical casing 2 includes a disk-shaped portion 2b and a cylindrical portion 2a. The right end in FIG. 1 of the cylindrical portion 2a that constitutes the cylindrical casing 2 is crimped to the disk-shaped lid portion 3 via packings 7a and 7b. The rotation center shaft 5 is rotatably supported inside the lid portion 3 in the radial direction by the housing 4 via sealed bearings 6a, 6b, 6c, and 6d. As the sealed bearings 6a, etc., for example, oil-sealed bearings can be employed. Hereinafter, the sealed bearings 6a, 6b, 6c and 6d may be simply referred to as bearings 6a, 6b, 6c and 6d in this specification.

In the illustrated embodiment, the housing 4 is sealed by the presence of packings 7a, 7b and bearings 6a, 6b, 6c, 6d.

The coreless motor 1 has a cylindrical coil 8 and a rotor 12 inside a housing 4 .

The cylindrical coil 8 is arranged concentrically with respect to the rotation center axis 5 and is supported by a stator supported by the housing 4 at one end face (the right end face in the embodiment shown in FIG. 1). It extends in the direction in which the axis 5 extends.

The cylindrical coil 8 is an energizable ironless coil. In the illustrated embodiment, a laminate structure of conductive metal sheets formed by overlapping a plurality of linear portions spaced apart in the longitudinal direction, which is the direction in which the rotation center axis 5 extends in FIG. It is formed in a cylindrical shape. The thickness in the radial direction is, for example, 5 mm or less and has a predetermined rigidity. Such a cylindrical coil is manufactured, for example, by the manufacturing method described in Japanese Patent No. 3704044.

The rotor 12 is arranged concentrically with respect to the rotation center shaft 5 and supported by the rotation center shaft 5 on the center side in the radial direction. In the embodiment shown in FIG. 1, the rotor 12 consists of an inner yoke 9 and an outer yoke 10 which radially sandwich the cylindrical coils 8 between each other. The outer yoke 10 has a magnet 11 on its radial inner surface facing the inner yoke 9 . As a result, a magnetic field having a doughnut-shaped cross section is formed between the inner yoke 9 and the outer yoke 10 having the magnet 11 on the radially inner surface, which sandwiches the cylindrical coil 8 between them, forming a magnetic circuit. It is

In the embodiment shown in FIG. 1, the magnets 11 are arranged on the radial inner surface of the outer yoke 10, but instead of this, the magnets 11 are arranged on the radial outer surface of the inner yoke 9. can also

A liquid refrigerant 20 is contained within the sealed housing 4 . In the embodiment shown in FIG. 1, the disc-shaped lid 3 of the housing 4 has an opening 14 which is sealed by a plug 15 .

After the plug 15 is removed from the opening 14 and a predetermined amount of liquid refrigerant 20 is introduced into the housing 4 , the opening 14 is closed again with the plug 15 to maintain the sealed state of the housing 4 .

As the liquid refrigerant 20, oil used for lubricating mechanical operating parts, antifreeze liquid, water, or the like can be used.

In the coreless motor 1 shown in FIG. 1, a magnetic field having a doughnut-shaped cross section is formed between the inner yoke 9 and the outer yoke 10. By supplying a predetermined current to the cylindrical coil 8, the rotor 12 is moved to the center of rotation. It rotates in the circumferential direction of the shaft 5 . The radially inner side of the inner yoke 9 forming the rotor 12 is supported by the rotation center shaft 5, whereby the rotation center shaft 5 also rotates in the circumferential direction indicated by the arrow 21 in FIG.

As shown in FIGS. 1 and 11(a), the liquid refrigerant 20 contained in the housing 4 has a structure in which the liquid surface extending in the axial direction in a stationary state contacts the outer peripheral surface of the outer yoke 10. .

When the rotor 12 rotates in the circumferential direction of the rotation center axis 5, the liquid refrigerant 20 in contact with the outer peripheral surface of the outer yoke 10 is taken along by the outer peripheral surface of the outer yoke 10, and the outer yoke 10 rotates in the circumferential direction. , and rises on the outer peripheral surface of the outer yoke 10 in the circumferential direction. The liquid refrigerant 4 that rises in the circumferential direction on the outer peripheral surface of the outer yoke 10 in the housing 4 is then pushed along the outer peripheral surface of the outer yoke 10 by its weight toward the bottom surface of the housing 4 in the horizontal state shown in FIG. fall to. While the liquid refrigerant 20 repeats such a flow operation due to the rotary motion of the rotor 12, a cross-sectional doughnut is formed between the inner yoke 9 and the outer yoke 10 that sandwich the cylindrical coil 8 between them in the radial direction. A portion of the liquid refrigerant 20 flows into the space portion having the shape of the groove from the left and right ends in FIG. 1 . The liquid refrigerant 20 that has flowed in comes into contact with the cylindrical coil 8 whose temperature begins to rise due to operation.

In this way, the cylindrical coil 8 is cooled by a part of the liquid refrigerant 20 coming into contact with the cylindrical coil 8 which is generating heat. In addition, the liquid coolant 20, which has taken heat from the cylindrical coil 8 that is generating heat, flows through the housing 4, thereby transferring heat to the housing 4 via the liquid coolant 20, and the temperature of the housing 4 rises. Heat is dissipated from the entire outer surface of 4 . As a result, overheating of the coils during operation of the coreless motor is suppressed, and an excessive current is supplied to the coils to enable the coreless motor 1 to output a high rotational speed.

A rotation center shaft 5 extending in the axial direction at the center of a closed housing 4, and a rotation center shaft 5 fixedly arranged concentrically with respect to the rotation center shaft 5 in the housing 4 and extending in the direction in which the rotation center shaft 5 extends. and a cylindrical inner yoke 9 and an outer yoke 10 which are arranged concentrically with respect to the rotation center axis 5 and sandwich the cylindrical coil 8 in the radial direction. or the inner surface of the outer yoke 10, and a rotor 12 that rotates in the circumferential direction of the rotation center shaft 5. 1, the liquid surface of the liquid coolant 20 extending in the axial direction in the stationary state shown in FIG. The structure in contact with the coil 8 suppresses overheating of the coil during operation of the motor.

In the conventional cooling mechanisms for electric motors proposed in Patent Documents 3 to 6, a cylindrical coil 8 is thus formed between an inner yoke 9 and an outer yoke 10 which are radially sandwiched between each other. A mechanism has not been proposed in which the liquid refrigerant is caused to flow into the donut-shaped space in cross section by the rotation of the rotor 12, the liquid refrigerant is brought into contact with the cylindrical coil 8 that is generating heat, and heat is taken away from the cylindrical coil 8. rice field.

Further, in this embodiment, as described above, the liquid refrigerant 20 contained in the sealed housing 4 is miniaturized by rotating the rotor 12 in the circumferential direction of the rotation center shaft 5 at high speed. , is atomized, becomes a spray state, and flows through the housing 4 at a high speed. The atomized liquid coolant 20 that flows at high speed inside the housing 4 passes through a donut-shaped gap formed between the radially inner side of the magnet 11 and the radially outer side of the cylindrical coil 8 and the inner yoke 9 . and the radially inner side of the cylindrical coil 8 .

The cylindrical coil 8 supplied with electric current generates heat, and part of the atomized liquid coolant 20 in contact with the radially inner surface and the radially outer surface of the cylindrical coil 8 is heated by the high-temperature cylindrical coil. Vaporized by 8.

As a result, the internal space of the housing 4 becomes a gas-liquid mixed state in which the liquid refrigerant atomized and atomized by the rotor 12 rotating at high speed exists. The rotor 12 rotates at a high speed in this sealed gas-liquid mixed atmosphere. The rotor 12, which rotates at high speed, causes the atomized gas-liquid mixture to flow through the sealed housing 4, so that the cylindrical coil generates heat when energized, compared to when the housing 1 is filled only with gas. Heat conduction from 8 to housing 4 is improved.

As a result, the cylindrical coil 8 is energized, the rotor 12 starts to rotate, and the temperature of the cylindrical coil 8 begins to rise. The temperature also begins to rise, and the temperatures of the disk-shaped portion 2b and the cylindrical portion 2a gradually approach the temperature of the cylindrical coil 8. As shown in FIG. In this way, heat is dissipated from the wide heat dissipating area of the outer surfaces of the disk-shaped portion 2b and the cylindrical portion 2a.

As a result, overheating of the cylindrical coil 8 during operation of the coreless motor 1 is suppressed, and an excessive current is supplied to the cylindrical coil 8 to allow the coreless motor 1 to output high rotational speed.

In the embodiment shown in FIG. 1, the liquid refrigerant 20 contained in the housing 4 which is sealed is contained in the housing 4 in contact with a portion of the rotor 12 . As soon as the rotor 12 rotates, the liquid refrigerant 20 starts to flow inside the housing 4 .

Although not shown, the liquid refrigerant 20 contained in the housing 4 may be configured so as not to contact a portion of the rotor 12 . Even in this case, the rotor 12 rotates at a high speed in the housing 4, so that a high-speed airflow is generated in the housing 4 in the rotation direction of the rotor 12, and the liquid refrigerant 20 flows in the housing 4 due to the airflow. get started.

In the embodiment shown in FIG. 1, the outer yoke 8 has holes 13a, 13b, 13c, 13d radially penetrating the outer yoke 8. In the embodiment shown in FIG.

When the rotor 12 rotates, the liquid coolant 20 is allowed to flow radially inwardly of the outer yoke 10 through the holes 13a, 13b, 13c, and 13d.

Therefore, it efficiently comes into contact with the cylindrical coil 8 located radially inside the outer yoke 10, efficiently takes heat from the heat-generating cylindrical coil 8, and contacts the inner wall surface of the housing 4 by flowing. Heat can be efficiently transferred to the housing 4. - 特許庁

In addition, since the rotor 12 rotates at high speed in the circumferential direction of the rotation center shaft 5, the flow state of the liquid refrigerant 20 in the housing 4 is further activated, and the above-described gas-liquid refrigerant in the inner space of the housing 4 is more efficiently discharged. A mixed condition will arise.

As described above, the liquid refrigerant 20 contained in the sealed housing 4 is in contact with a portion of the rotor 12, or even if it is not in contact, the high-speed rotation of the rotor 12 causes the interior space of the housing 4 to expand. is in a gas-liquid mixed state, but since the rotor 12 is provided with the holes 13a penetrating in the radial direction as described above, the gas-liquid mixed state is more efficiently generated and the cylindrical coil 8 that is generating heat. There is more efficient heat transfer from the to the housing 4 .

In the embodiment shown in FIG. 1, a plurality of holes 13a, 13b, 13c, and 13d are formed at predetermined intervals in the circumferential direction of the cylindrical outer rotor 10 on the left end side in FIG. The number and positions of the holes are not limited to those shown in FIG.

Further, in this embodiment, instead of the sealing structure with the opening 14 and the plug 15, a valve body 36 employed in the embodiment shown in FIG. It is also possible to make the housing 4 to be sealed again when the pressure inside the housing 4 is blown out from the inside of the housing 4 to the outside when the pressure exceeds the predetermined pressure.

In this manner, the sealed and closed structure of the housing 4 is such that the liquid refrigerant 20 contained in the housing 4 flows through the housing 4 due to the rotation of the rotor 12, comes into contact with the cylindrical coil 8, absorbs heat, All that is necessary is to maintain a hermetic state that allows heat to be transferred to 4 .

(Embodiment 2)
FIG. 2 illustrates an example of an embodiment in which the liquid coolant 20 contained within the sealed housing 4 is caused to flow more efficiently within the housing 4 by the rotation of the rotor 12 .

The rotor 12 has stirring blades 16, 16 extending toward the inner peripheral surface of the cylindrical portion 2a of the housing 4. As shown in FIG. Since other structures are the same as those of the embodiment shown in FIG. 1, common members are denoted by common reference numerals and descriptions thereof are omitted.

The rotor 12 is provided with the stirring blades 16, 16 extending toward the inner peripheral surface of the cylindrical portion 2a of the housing 4, so that the rotor 12 rotates in the circumferential direction of the rotation center shaft 5, causing The flow of the liquid refrigerant 20 inside the housing 4 is more reliable and strong.

In the embodiment shown in FIG. 2, the stirring blades 16, 16 are radially outward of the rotor 12 and have a radius from the right end surface in FIG. It extends outward in the direction and toward the inner surface side of the disk-shaped portion 2 b of the housing 4 .

Therefore, even when the coreless motor 1 is arranged as shown in FIGS. 1 and 2 and the liquid refrigerant 20 is accommodated as shown in FIGS. , the disk-shaped portion 2b of the housing 4 faces downward, and the tip of the rotation center shaft 5 extending outward from the housing 4 faces upward. Even when positioned on the disk-shaped portion 2b side, the flow of the liquid refrigerant 20 in the housing 4 caused by the rotation of the rotor 12 in the circumferential direction of the rotation center shaft 5 is more reliable and strong. You will be able to

(Embodiment 3)
FIG. 3 is a conceptual diagram illustrating another example of an embodiment in which the liquid refrigerant 20 contained within the sealed housing 4 is caused to flow more efficiently within the housing 4 by the rotation of the rotor 12.

Cylindrical coil 8 is provided with stirring projections 17 extending radially outwards.

When the rotor 12 rotates, the centrifugal force generated by the rotation of the rotor 12 may press the liquid refrigerant 20 against the radial outer surface of the cylindrical coil 8 as shown in FIG.

In FIG. 3, the magnet 11 is arranged on the radial inner surface of the outer yoke 10, and the liquid refrigerant 20 enters around the magnet 11 to form a liquid pool.

Since the agitating projections 17 extending radially outward from the cylindrical coil 8 enter the liquid pool, the liquid pool is eliminated when the rotor 12 rotates, and the liquid refrigerant 20 efficiently flows within the housing 4. become.

(Embodiment 4)
In the embodiment shown in FIGS. 1 and 2, the central axis of rotation, which extends axially in the center of the closed housing 4 and is rotatably supported by the housing 4, in the embodiment shown in FIG. It is composed of a first rotation center shaft 5a, a second rotation center shaft 5b, and a third rotation center shaft 5c extending in the left-right direction in FIG.

Further, in the embodiment shown in FIG. 4, a disk-shaped lid portion 3 is rotatably attached to the right end opening in FIG. The third rotation center shaft 5 c is fixed to the disk-shaped lid portion 3 and rotates together with the disk-shaped lid portion 3 .

In the embodiment of FIGS. 1 and 2, the rotor 12 is supported radially inwardly by the rotation center shaft 5, and the rotation of the rotor 12 directly causes the rotation center shaft 5 to rotate. In the embodiment shown in FIG. 4, the housing 4 includes a speed reducer comprising a planetary gear mechanism for transmitting the rotational motion of the rotor 12 about the rotation center shaft to the rotation motion of the third rotation center shaft 5c, which is the rotational motion output section. is deployed in

In the embodiment shown in FIGS. 1 and 2, the rotation center shaft 5 is the rotational motion output portion of the coreless motor 1, but due to the above-described configuration, in the embodiment shown in FIG. It is a rotary motion output part in the coreless motor 1 .

In the embodiment shown in FIGS. 1 and 2, the disc-shaped lid 3 of the housing 4 has an opening 14 sealed by a plug 15, the plug 15 being removed from the opening 14 and a predetermined amount of After the liquid refrigerant 20 is introduced into the housing 4, the opening 14 is closed again with the plug 15 to keep the housing 4 sealed.

In contrast, in the embodiment shown in FIG. 4 the closed housing 4 is provided with the valve body 36 . In FIG. 4, the valve body 36 is arranged in the cylindrical portion 2a of the housing 4. As shown in FIG. The valve body 36 is detachable from the cylindrical portion 2a. After the valve body 36 is removed from the cylindrical portion 2a and the liquid refrigerant 20 is introduced into the housing 4, the valve body 36 is reattached as shown in FIG. , the housing 4 is sealed by being attached to the cylindrical portion 2a.

The valve body 36 has a function of preventing leakage of liquid from the inside of the housing 4 to the outside. In addition, when the pressure inside the housing 4 exceeds a predetermined pressure, gas is ejected from the inside of the housing 4 to the outside, and when the pressure inside the housing 4 falls below the predetermined pressure, the housing 4 is sealed again. It's becoming

Other configurations are basically in common with the first and second embodiments described with reference to FIGS. Therefore, members common to the embodiment shown in FIGS. 1 and 2 are denoted by common reference numerals in FIG. 4, and descriptions thereof are omitted.

On the tip side (left side in FIG. 4) of the first rotation center shaft 5a that supports the radially inner side of the rotor 12 and whose right end in FIG. is fixed to a first sun gear 30 that constitutes a reduction gear consisting of a planetary gear mechanism.

When the first rotation center shaft 5a and the first sun gear 30 rotate in accordance with the rotation of the rotor 12, this rotational motion is transmitted from the first sun gear 30 via the first planetary gears 31 and the first carrier 32 to the second rotation. It is transmitted to the center shaft 5b, and the second rotation center shaft 5b rotates in the same circumferential direction as the first rotation center shaft 5a.

A second sun gear 33 that constitutes a speed reducer composed of a planetary gear mechanism is fixed to the tip side (left side in FIG. 4) of the second rotation center shaft 5b.

When the second sun gear 33 rotates due to the rotation of the second rotation center shaft 5b, this rotational movement moves from the second sun gear 33 to the third rotation center shaft 5c via the second planetary gears 34 and the second carrier 35. It is transmitted to the disc-shaped cover portion 3 that is fixedly supported, and the third rotation center shaft 5c rotates in the same circumferential direction (for example, the direction indicated by the arrow 21) as the second rotation center shaft 5b.

In this embodiment as well, the rotor 12 rotates along the first rotation center axis by supplying a predetermined current to the cylindrical coil 8 under a donut-shaped cross-sectional magnetic field formed between the inner yoke 9 and the outer yoke 10. It rotates in the circumferential direction of 5a. The radially inner side of the inner yoke 9 forming the rotor 12 is supported by the first rotation center shaft 5a, whereby the first rotation center shaft 5a also rotates in the circumferential direction.

The rotation of the first rotation center shaft 5a is transmitted to and output from the third rotation center shaft 5c via the reduction gear including the planetary gear mechanism described above.

In the embodiment shown in FIG. 4, the above-described two-stage speed reduction mechanism is employed, and the torque generated by the rotation of the rotor 12 is increased and output from the third rotation output shaft 5c.

The speed reducer configured as described above includes a cylindrical gear case 18 extending in the direction in which the first rotation center shaft 5a, the second rotation center shaft 5b, and the third rotation center shaft 5c, which are the rotation center shafts, extend. are housed in

In the coreless motor 1 of the embodiment shown in FIG. 4 as well, the liquid refrigerant 20 contained in the sealed housing 4 causes the rotor 12 to rotate in the circumferential direction of the first rotation output shaft 5a as described above. Thus, it flows inside the housing 4 .

In the embodiment shown in FIG. 4, the liquid refrigerant 20 contained in the housing 4 is structured such that the liquid surface extending in the axial direction in a stationary state contacts the outer peripheral surface of the outer yoke 10 .

Therefore, as described in the embodiment shown in FIG. , and flows in the circumferential direction of rotation of the outer yoke 10 along with the outer peripheral surface of the outer yoke 10 , and rises in the circumferential direction on the outer peripheral surface of the outer yoke 10 . The liquid refrigerant 4 that rises in the circumferential direction on the outer peripheral surface of the outer yoke 10 in the housing 4 is then pushed along the outer peripheral surface of the outer yoke 10 by its weight toward the bottom surface of the housing 4 in the horizontal state shown in FIG. fall to. While the liquid refrigerant 20 repeats such a flow operation due to the rotational motion of the rotor 12, it flows from the left and right ends in FIG. The liquid refrigerant 20 at the part comes into contact with the cylindrical coil 8 whose temperature begins to rise due to operation.

In this way, the cylindrical coil 8 is cooled by a part of the liquid refrigerant 20 coming into contact with the cylindrical coil 8 which is generating heat. In addition, the liquid coolant 20 that takes heat from the heat-generating cylindrical coil 8 flows through the housing 4 , thereby transferring heat from the liquid coolant 20 to the housing 4 , increasing the temperature of the housing 4 . Heat is dissipated from the entire outer surface. As a result, overheating of the coils during operation of the coreless motor is suppressed, and an excessive current is supplied to the coils to enable the coreless motor 1 to output a high rotational speed.

In addition, part of the liquid coolant 20 flows into the cylindrical gear case 18 due to the liquid coolant 20 flowing in this way. Therefore, by using the oil used for lubricating the mechanical operating parts as the liquid coolant 20, it is possible to lubricate each gear part in the speed reducer composed of the planetary gear mechanism.

In addition, as the rotor 12 rotates at high speed in the circumferential direction of the rotation center shaft 5, the internal space of the housing 4 enters a gas-liquid mixed state as described above. It is possible to suppress overheating of the cylindrical coil 8 during operation of the coreless motor 1, supply an excessive current to the cylindrical coil 8, and output the coreless motor 1 at high rotation. This is the same as described in the first and second embodiments.

In this embodiment, the housing 4 is provided with a valve body 36 having the functions described above. Therefore, for example, when the coreless motor 1 is operated at high output for a long time and the pressure inside the housing 4 exceeds a predetermined pressure, gas is ejected from the inside of the housing 4 to the outside. As a result, the coreless motor 1 can be operated at high output for a long period of time, and when the pressure in the housing 4 exceeds the permissible internal pressure, the above-described ejection (exhaust) by the valve body 36 can be performed. , the pressure in the housing 4 can be prevented from exceeding the allowable internal pressure.

In this embodiment, the housing 4 includes a speed reducer composed of a planetary gear mechanism, which transmits the rotational motion of the rotor 12 about the rotational center axis to the rotational motion of the third rotational center shaft 5c, which is the rotational motion output section. deployed inside.

Using the oil used for lubricating the mechanical operating parts as the liquid coolant 20 makes it possible to lubricate each gear part in the speed reducer composed of the planetary gear mechanism.

As a result, in the embodiment shown in FIG. 4, although the reduction gear consisting of the planetary gear mechanism is arranged in the housing 4, the occurrence of noise due to the presence of a plurality of gears that engage with each other in rotational motion is suppressed, and the gears are quietly operated. It can be a coreless motor driven. The presence of moderately viscous oil stably maintains the rotating portion, which is composed of a plurality of gears that constitute the speed reducer.

In addition, since the speed reducer is composed of a plurality of gears, metal powder is generated due to metal wear caused by the rotation of the gears. It may get dirty.

However, since the rotor 12 is provided with the magnets 11 as described above, the metal powder is attracted to the magnets 11, preventing the oil from being contaminated.

The gears that constitute the speed reducer that is a planetary gear mechanism can be made of synthetic resin or stainless steel. By doing so, even if water is used as a coolant, the occurrence of rust can be prevented. If oil is used as the coolant, rust can be prevented even if the gear is made of iron. So-called reduced water (electrolyzed water) may be used. Here, if the speed reducer composed of the planetary gear mechanism is made of synthetic resin, the above-mentioned problem of metal powder generation due to metal abrasion due to rotation of the gear can be eliminated.

Grease is generally used in motors, and high-viscosity materials such as grease are subjected to centrifugal force as the motor rotates, and move away from the application point. In contrast, the present invention uses oil, so grease is not necessary. In the first place, the grease used for lubrication of the gear portion of the gear mechanism generally liquefies at about 80° C., and the effect of adopting the grease cannot be obtained. For this reason, when grease is used to lubricate gears, it is common practice to prevent the temperature from reaching about 80°C.

In the coreless motor of this embodiment, the temperature of the cylindrical coil portion that generates heat when energized generally exceeds 100° C. From this point of view as well, the use of grease is not suitable.

It should be noted that, instead of using the valve body 36, the sealing structure using the opening 14 and the plug 15 described in the first embodiment can be adopted.

(Embodiment 5)
5 to 7 illustrate another embodiment of the fourth embodiment (FIG. 4). In the fourth embodiment (FIG. 4), as described above, the speed reducer extends in the direction in which the first rotation center shaft 5a, the second rotation center shaft 5b, and the third rotation center shaft 5c, which are the rotation center shafts, extend. It is housed in a cylindrical gear case 18 that

In the fifth embodiment shown in FIGS. 5-7, the gear case 18 is provided with a hole 19 radially penetrating the gear case 18 .

As described above, the rotor 12 rotates in the circumferential direction of the first rotary output shaft 5 a , causing the liquid refrigerant 20 contained in the closed housing 4 to flow within the housing 4 . Part of the liquid coolant 20 flowing in the housing 4 contacts the heating cylindrical coil and evaporates, so that the internal space of the housing 4 becomes a gas-liquid mixed state, and the cylindrical coil heats up when energized. Heat is efficiently conducted from 8 to housing 4 .

At the same time, the liquid refrigerant 20 flowing inside the housing 4 is utilized to lubricate each gear portion in the speed reducer composed of a planetary gear mechanism.

In the embodiment shown in FIGS. 5 to 7, the cylindrical gear case 18 that houses the speed reducer is provided with holes 19 radially penetrating the gear case 18 so that the liquid refrigerant 20 is It is efficiently supplied to the speed reducer. Therefore, the lubrication of each gear portion by the liquid coolant 20 is more effectively performed.

As shown in FIG. 12, in the stationary state, the liquid surface of the liquid refrigerant 20 extending in the axial direction can be brought into contact with the outermost peripheral edge of the planetary gear mechanism 40 in the radial direction.

In this way, the liquid refrigerant 20 is supplied to the speed reducer as soon as the rotor 12 starts rotating, and the liquid refrigerant 20 effectively lubricates the gears.

In the embodiment shown in FIGS. 5 to 7, a plurality of gears are provided at predetermined intervals in the circumferential direction of the cylindrical gear case 18 and at predetermined intervals in the longitudinal direction of the cylindrical gear case 18, respectively. A hole 19 of is formed.

The number of holes 19 and the positions where they are formed can be set variously.

(Embodiment 6)
8 to 10 illustrate another embodiment of the fourth embodiment.

8 to 10 illustrate the sealing structure of the housing 4 by the opening 14 and the plug 15 and the sealing structure of the housing 4 by the valve body 36, which were described in the first and fourth embodiments. are omitted.

In the fourth embodiment (FIG. 4), the rotation center shaft constituted by the first rotation center shaft 5a, the second rotation center shaft 5b, and the third rotation center shaft 5c is replaced by the fixed shaft 5d passing through the housing 4. I have to. The housing 4 is rotatably supported by the fixed shaft 5d via an oil seal while the inside is sealed. A cylindrical portion 2a forming the housing 4 serves as a rotary motion output portion.

In the embodiments of FIGS. 8 to 10, the radial center side of the inner yoke that constitutes the rotor 12 is rotatably supported by the fixed shaft 5d. An outer circumference 9a of the inner yoke rotatably supported by the fixed shaft 5d on the radial center side constitutes the first sun gear in the fourth embodiment (FIG. 4).

In the fourth embodiment (FIG. 4), the rotational motion of the first sun gear that rotates together with the first rotation center shaft is transmitted through the first planetary gear, the first carrier, the second sun gear, the second planetary gear, and the third carrier. It was transmitted to the third rotary output shaft, which is the rotary motion output section.

In the embodiment shown in FIGS. 8 to 10, the rotational motion of the first sun gear consisting of the outer circumference of the radial center side portion 9a of the inner yoke rotatably supported by the fixed shaft 5d is controlled by the first planetary gear, the first The fixed shaft 5d of the cylindrical portion 2a that constitutes the housing 4, which is a rotary motion output portion via the carrier, the second sun gear, the second planetary gear, and the third carrier that are rotatably supported by the fixed shaft 5d. Circumferential rotational motion about the center is imparted.

Other basic structures and mechanisms are the same as those described in the fourth embodiment (FIG. 4).

Also in this embodiment, the liquid refrigerant 20 contained in the sealed housing 4 flows in the housing 4 as the rotor 12 rotates in the circumferential direction of the fixed shaft 5d. As a result, the internal space of the housing 4 is in a gas-liquid mixed state, and heat is efficiently conducted from the cylindrical coil 8, which generates heat when energized, to the housing 4, thereby suppressing overheating of the cylindrical coil 8 during operation of the coreless motor 1. As in the first and second embodiments, it is possible to supply an excessive current to the cylindrical coil 8 so that the coreless motor 1 can output a high rotational speed.

In addition, by using the oil used for lubricating the mechanical operation parts as the liquid refrigerant 20, it is possible to lubricate each gear part in the reduction gear consisting of the planetary gear mechanism. It can be a silently driven coreless motor, which is located in the housing 4 but suppresses the presence of a plurality of intermeshing gears in rotational motion.

(Test example)
A test was conducted using a coreless motor (CPH80F) commercially available from the applicant of the present application. This coreless motor includes a cylindrical coil arranged concentrically with respect to the central axis of rotation in a housing, one end face of which is supported by a stator, and extending in the direction in which the central axis of rotation extends; The structure includes a rotor arranged concentrically with respect to the shaft and rotating in the circumferential direction of the central axis of rotation.

Both of the two coreless motors (CPH80F) used for the test had a sealed structure, one of which contained water as a liquid refrigerant, and the other of which was operated in a normal state without water. .

The test operation was carried out simultaneously in the same room with an input of 24Vdc, a torque of 1Nm, and an output of 380W for both units. The results are shown in Table 1 (Example (with liquid refrigerant (water)) and Table 2 (Comparative Example (without liquid refrigerant (water)) below.

Based on the test results, it was found that liquid refrigerant was stored in the sealed housing of the coreless motor, and the rotation of the rotor caused the liquid refrigerant to flow in the housing and bring the liquid refrigerant into contact with the heat-generating cylindrical coil. By vaporizing a part of the housing to create a gas-liquid mixed state in the housing, the heat transfer efficiency in the housing is improved, and the temperature of the housing rises following the temperature rise of the cylindrical coil. It was confirmed that the heat was well dissipated.

(Embodiment of generator)
Although embodiments of coreless motors have been described above, the present invention is not limited to the embodiments described above. The structure of the motor is basically the same as that of the generator. In the configuration and structure of the coreless motor described above, the power generator is a generator that generates power by rotating the rotor by the input rotational force. Therefore, in the present invention, an embodiment of a power generator having the configuration and structure described above is possible.

Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and can be variously modified within the technical scope grasped from the description of the claims.

Claims (8)

A closed body rotatably supported by a shaft, having a cylindrical portion forming a rotary motion output portion, containing a liquid refrigerant therein, and having a cylindrical coil and a rotor disposed therein. with motor housing,
the cylindrical coil is fixedly disposed within the motor housing;
The rotor comprises a cylindrical inner yoke and a cylindrical outer yoke which sandwich the coils in the radial direction, and has magnets on the outer surface of the inner yoke or the inner surface of the outer yoke. The outer yoke has a hole extending radially therethrough ,
When the coil is energized, the rotor that rotates in the motor housing causes the liquid coolant to flow in the motor housing and through the holes provided in the outer yoke ,
the flowing liquid refrigerant comes into contact with the coil that is generating heat due to energization and takes heat from the coil;
The liquid refrigerant that has taken heat from the coil contacts the inner wall of the cylindrical portion of the motor housing rotating about the shaft, thereby transferring heat to the motor housing rotating about the shaft. tell,
A coreless motor in which heat is dissipated from an outer wall surface of the cylindrical portion of the motor housing rotating about the shaft. A closed body rotatably supported by a shaft, having a cylindrical portion forming a rotary motion output portion, containing a liquid refrigerant therein, and having a cylindrical coil and a rotor disposed therein. with motor housing,
the cylindrical coil is fixedly disposed within the motor housing;
The rotor comprises a cylindrical inner yoke and a cylindrical outer yoke which sandwich the coils in the radial direction, and has magnets on the outer surface of the inner yoke or the inner surface of the outer yoke. The outer yoke has a hole extending radially therethrough ,
By energizing the coil, the rotor rotating within the motor housing causes the liquid refrigerant to flow at high speed within the motor housing and through the holes provided in the outer yoke. It is brought into contact with the heat-generating coil to take heat from the coil, and the atmosphere in the motor housing is made into a gas-liquid mixed state by the high-speed rotation of the rotor, and the rotor rotating around the shaft from the coil. Improves heat transfer to the motor housing,
The liquid refrigerant that has taken heat from the coil contacts the inner wall of the cylindrical portion of the motor housing rotating about the shaft, thereby transferring heat to the motor housing rotating about the shaft. tell,
A coreless motor in which heat is dissipated from an outer wall surface of the cylindrical portion of the motor housing rotating about the shaft. A closed body rotatably supported by a shaft, having a cylindrical portion forming a rotary motion output portion, containing a liquid refrigerant therein, and having a cylindrical coil and a rotor disposed therein. with motor housing,
the cylindrical coil is fixedly disposed within the motor housing;
The rotor comprises a cylindrical inner yoke and a cylindrical outer yoke which sandwich the coils in the radial direction, and has magnets on the outer surface of the inner yoke or the inner surface of the outer yoke. The outer yoke has a hole extending radially therethrough ,
Due to the rotation of the rotor, the liquid refrigerant flows into a space having a doughnut-shaped cross section formed between the inner yoke and the outer yoke, and contacts the coils that generate heat. and rotates around the shaft in the space between the radially outer side of the outer yoke and the inner wall surface of the cylindrical portion of the motor housing rotating around the shaft. Flowing within the motor housing and through the holes provided in the outer yoke , transferring heat from the liquid coolant to the motor housing as it rotates about the axis, and in the radial direction of the coil A coreless motor that dissipates heat from an outer wall surface of the cylindrical portion of the motor housing that rotates around the shaft and has a larger surface area than the outer peripheral surface of the outer yoke located outside. 4. The coreless motor according to any one of claims 1 to 3, wherein a gear mechanism for transmitting rotational motion of said rotor to rotational motion of said motor housing about said shaft is built in said motor housing. 5. A coreless motor according to claim 4, wherein said liquid refrigerant is oil used for lubricating said gear mechanism. 4. The coreless motor according to any one of claims 1 to 3, wherein the liquid coolant is antifreeze. 4. The coreless motor according to claim 1, wherein the liquid coolant is water. A generator comprising the configuration and structure of the motor according to any one of claims 1 to 3.

Images