JPH11341757A - Motor, power transmission apparatus, and hybrid vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To downsize a device for a motor having two rotating shafts, capable of rotating relative to each other. SOLUTION: This motor is constituted by disposing an inner rotor 110, a stator, and an outer rotor 170 concentrically from its center. Both rotors are relatively rotatably-connected to two rotating shafts. The inner rotor 110 is a permanent magnet containing type rotor, and the outer rotor 170 is a wound rotor. In the stator, a plurality of independent cores wound concentratedly are disposed in a circumferential form, and a section between adjacent cores is fixed through resin-molding. The stator has a yoke-free structure. A magnetic circuit penetrating from the inner rotor 110 through the stator to the outer rotor 170 is formed in the motor, energization for the stator is controlled by one drive circuit to control the operation of the motor. It is thus possible to use the motor as a power transmission device, which transmits power from one rotating shaft to the other.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a motor having two relatively rotatable rotating shafts arranged coaxially, a power transmission device using the motor, and a hybrid vehicle.

[0002]

2. Description of the Related Art An electric motor having two rotating shafts is used for various purposes. One of the uses is as a power transmission device for a hybrid vehicle. FIG. 55 shows a configuration of such a hybrid vehicle, for example. FIG. 55 shows an example of a configuration of a parallel-type hybrid vehicle including an engine EG, a clutch motor CM, and an assist motor AM and capable of running with power from the engine EG. The clutch motor CM is a pair rotor motor in which both the outer rotor RO and the inner rotor RI can relatively rotate. As shown, the clutch motor C
In M, the output shaft of the engine EG is connected to the outer rotor RO, and the drive shaft DS is connected to the inner rotor RI. Drive wheels are connected to the drive shaft DS via a reduction gear or the like. In FIG. 55, illustration of the drive wheels is omitted. Also,
The rotor R of the assist motor AM is connected to the drive shaft DS. The assist motor AM is a synchronous motor, and its stator S is fixed to a case. Note that the inner rotor RI of the clutch motor CM and the assist motor AM
In each of the stators, a coil is wound, and the operation of each motor can be controlled by energizing the coil through drive circuits DC1 and DC2.

[0003] In the hybrid vehicle having the above configuration,
Due to relative slip between the outer rotor RO and the inner rotor RI of the clutch motor CM, a part of the power output from the engine EG is regenerated as electric power,
The remaining power can be transmitted to the inner rotor RI, that is, to the drive shaft DS. In addition, the assist motor AM is driven using the regenerated electric power to add power to the drive shaft DS. With such an action, in the above hybrid vehicle,
The power output from the engine EG is converted into various rotational speeds and torques, and the power is output from the drive shaft DS to travel. By coupling the assist motor AM to the clutch motor CM having two rotation shafts as described above, a power transmission device can be configured.

The configuration shown in FIG. 55 requires two electric motors, the clutch motor CM and the assist motor AM, to perform the above-described torque conversion, and has a disadvantage that the size of the device becomes large. As a technique for solving such disadvantages and reducing the size of the apparatus, a technique in which a clutch motor CM and an assist motor AM are coaxially arranged has been proposed (for example, a technique described in Japanese Patent Application Laid-Open No. 9-46815). FIG. 56 shows a cross-sectional view of a motor based on such a configuration. As shown in the figure, the electric motor includes a first rotor 1210 having a coil wound around a rotation axis, a second rotor 1310 having a permanent magnet affixed to the outside thereof, and a stator 1410 having a coil wound further outside. It has. The first rotor 1210 and the second rotor 1310 are relatively rotatable. The first rotor 1210 and the second rotor 1310 act like a clutch motor CM, and the second rotor 1310
And the stator 1410 act like an assist motor AM. With such an operation, the above-described torque conversion can be performed by the electric motor alone.

[0005]

However, in the motor having the structure shown in FIG. 56, it is possible to reduce the size in the axial direction, but it is not possible to sufficiently reduce the size in the radial direction. That is, the volume of the entire power transmission device cannot be reduced sufficiently, and the weight of the device cannot be reduced sufficiently.

[0006] In a conventional motor having two rotating shafts, it is necessary to supply electric power to a rotating rotor.
Such power supply is performed via a slip ring or a differential transformer, but there is a problem that durability is low when a slip ring is used, and efficiency is low when a differential transformer is used. There were challenges. This problem was common to the clutch motor CM shown in FIG. 55 and the electric motor shown in FIG.

Further, when a power transmission device is formed using a conventional motor having two rotating shafts, at least two drive circuits for driving the power transmission device are required.
For example, as shown in FIG. 55, when a power transmission device is configured by a combination of a clutch motor CM and an assist motor AM, two drive circuits DC1 and DC2 are required to drive each motor. Met. Also, the electric motor shown in FIG. 56 also requires two driving circuits, one for supplying electric power to first rotor 1210 and the other for supplying electric power to stator 1410. This complicates the configuration of the device and also causes problems such as an increase in size and weight.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and has as its first object to reduce the size of an electric motor having two relatively rotatable rotating shafts. It is a second object of the present invention to eliminate the need for a member for supplying power to a rotating rotor such as a slip ring. Further, it is a third object to provide an electric motor having a reduced number of drive circuits. It is another object of the present invention to provide a power transmission device for transmitting power from one rotation shaft to another rotation shaft and a hybrid vehicle as a device using such an electric motor.

[0009]

Means for Solving the Problems and Their Functions and Effects In order to solve at least a part of the above problems, the present invention employs the following constitution. A first electric motor according to the present invention is an electric motor having two relatively rotatable rotary shafts on the same axis, wherein a magnetic element which contributes to the formation of a magnetic circuit is concentric with the rotary shaft as a center. The first magnetic element, the second magnetic element, and the third magnetic element are provided in this order from the inside, and the two rotation axes are connected to any two of the first to third magnetic elements. The magnetic elements are coupled to each other, and each magnetic element is configured to form a magnetic circuit extending from the first magnetic element to the third magnetic element through the second magnetic element.

According to such an electric motor, by providing the above-mentioned three magnetic elements coaxially, as a first effect, the size of the entire apparatus can be reduced. The magnetic element in the present invention is a general term for a so-called rotor and a stator, and includes various elements that can contribute to the formation of a magnetic circuit, such as those using a permanent magnet, those wound with coils, and the so-called cage rotor. It is. Further, the first to third magnetic elements include two rotors and one stator, but any of the magnetic elements may correspond to the stator. Specifically, there are three types, those arranged from the inside as "rotor, rotor, stator", those arranged as "rotor, stator, rotor", and those arranged as "stator, rotor, rotor".

According to the motor of the present invention, in addition to the above-described effects, it is also possible to reduce the number of drive circuits for operating the motor to one as a second effect. By reducing the number of drive circuits, the size, weight, and the like of the entire device can be further reduced. The first and second effects will be described in comparison with a conventional motor (FIG. 56).

In the conventional motor shown in FIG. 56, the first rotor 1210 and the second rotor 131
0 and the stator 1410 in this order. The second rotor 1310 includes permanent magnets 1220 and 142 on inner and outer peripheral surfaces of a rotor yoke formed of a magnetic material, respectively.
0 is affixed. In an electric motor having such a structure,
The magnetic circuit is formed like Min and Mout shown in FIG. The magnetic circuit Min penetrating through the first rotor 1210 passes through the rotor yoke portion of the second rotor 1310 in the circumferential direction, and returns to the first rotor 1210 again. The magnetic circuit Mout penetrating through the stator 1410 circumferentially passes through the rotor yoke of the second rotor 1310 and returns to the stator 1410 again. Among the magnetic fluxes emitted from the first rotor 1210, almost no magnetic flux reaches the stator 1410. In order to drive such an electric motor, it is necessary to control the position and strength of the magnetic circuits Min and Mout. When two independent circuits are formed as shown in FIG. 56, a drive circuit is required for each magnetic circuit. As a result, the motor shown in FIG. 56 requires two drive circuits. Further, in order to form the two magnetic circuits in this manner, a rotor yoke portion is required for the rotor 1310 existing therebetween, and the size of the device in the radial direction has been increased.

On the other hand, according to the electric motor of the present invention, the first magnetic element, the second magnetic element, and the third magnetic element are arranged in this order from the inside of the rotating shaft. These magnetic elements are configured to be capable of forming a magnetic circuit extending from the innermost first magnetic element through the second magnetic element to the outermost third magnetic element. I have. That is, the magnetic circuit in the electric motor of the present invention is not formed separately as in the case of the electric motor shown in FIG. 56, but is formed as one circuit from the first magnetic element to the third magnetic element. You. In order to control the driving of the electric motor of the present invention,
What is necessary is just to control one magnetic circuit formed in this way.
Therefore, in the present invention, the number of drive circuits required for driving the electric motor can be reduced to one. Of course, this means that the minimum required driving circuit can be reduced to one, and the driving can be performed using two or more driving circuits. By configuring the second magnetic element so as not to have a portion in which the magnetic circuit passes in the circumferential direction, the size of the entire apparatus can be reduced. Of course, the point that the number of drive circuits can be reduced also contributes to downsizing of the entire device.

A second electric motor according to the present invention is a motor having two relatively rotatable rotary shafts on the same axis, wherein the first rotor and the stator are arranged concentrically around the rotary shaft from the inside. , A second rotor in order, the first rotor being coupled to one of the rotating shafts,
The rotor is coupled to the other of the rotation shafts, and the stator is formed by arranging a plurality of cores in a circumferential shape, and coupling the circumferentially adjacent cores with a non-magnetic material. It is characterized by the following.

According to such an electric motor, similarly to the first electric motor described above, the size of the entire device can be reduced, and the number of drive circuits can be reduced. Further, the electric motor of the present invention has an advantage that control for driving is easy for the following reason.

Controlling the operation of a motor having two rotors as proposed in the present invention is nothing less than controlling the rotational state of the two rotors. The present invention is capable of controlling the formation of a magnetic circuit by controlling one drive circuit and controlling the rotational state of these two rotors. In this case, for example, if the first rotor, the second rotor, and the stator are arranged in this order from the inside of the rotation shaft, the control of the first rotor allows
The reaction appears on the second rotor. Further, since the first rotor and the stator are separated, a large amount of energy is required to control the rotation of the first rotor by controlling the magnetic field in the stator portion, which is inefficient. Naturally, at this time, the rotation state of the second rotor is greatly affected. On the other hand, in the electric motor of the present invention, since the rotors are arranged inside and outside with the stator interposed therebetween, the respective rotations can be controlled without the above-mentioned problems.

Heretofore, only an electric motor having a stator disposed on the outermost side has been proposed. This seems to take into account the convenience of fixing the motor to the case or the like. However, even if the outermost shell is formed of a rotor, it is not so difficult to fix the case to the case if a bearing is used. From such a viewpoint, the present inventor:
The fixed idea that the outermost shell of a motor having two rotating shafts should be a stator has been removed, and a new structure that has not been assumed to be applied conventionally has been adopted.
As a result, the electric motor of the present invention was able to obtain the above-described effects.

Further, the electric motor of the present invention has a significant feature in the structure of the stator. Conventionally, the stator is formed by winding a coil around a core formed of a ring-shaped yoke portion and a plurality of salient poles (see stator 1410 in FIG. 56). On the other hand, in the stator of the present invention, a plurality of cores corresponding to the salient poles in FIG. That is, there is no ring-shaped yoke. Therefore, according to the stator having the structure of the present invention, no magnetic circuit is formed in the circumferential direction. That is, the magnetic circuit formed on the stator penetrates in the radial direction. As a result, a magnetic circuit is formed from the first rotor located on the inside of the stator to the second rotor located on the outside through the stator, and it is possible to form an electric motor having the various effects described above. .

The coupling between the cores of the stator may use any non-magnetic material. As long as each core can be fixed, it is also possible to leave a gap between each core. As a preferable example of the connection by the nonmagnetic material, the stator may be one in which the cores are fixed by a resin mold. In this case, the stator can be easily manufactured, and there is an advantage that the rigidity of the stator is increased.

The structure of the stator proposed in the above invention, that is, the structure having no yoke portion is also a completely new structure devised by the present inventors. As described above, conventionally, a structure in which salient poles are provided in a yoke portion has been adopted. This is because it has been desired to form a magnetic circuit also in the circumferential direction of the stator in order to efficiently drive the electric motor by preventing the magnetic flux from escaping to the outside. Another reason is that the provision of the yoke facilitates the formation of the stator.
On the other hand, in the present invention, as described above, it was necessary to form a magnetic circuit extending from the first rotor to the stator and reaching the second rotor. That is, in the present invention, it is necessary to avoid forming a magnetic circuit in the circumferential direction of the stator. From such a viewpoint, the inventor has taken away the fixed idea that the yoke portion exists in the stator, and has found an important significance in adopting a completely new structure in which each core is fixed without the yoke portion. Although the structure of forming the stator without the yoke portion was hard to imagine, he realized the possibility of fixing with a non-magnetic material, especially a resin mold, and devised the configuration of the present invention.

Further, in the electric motor according to the present invention, the stator has a coil wound around a plurality of cores, and is capable of generating a magnetic field by energizing the coil.
One of the first rotor and the second rotor is a rotor having a permanent magnet, and the other of the first rotor and the second rotor constitutes the stator and the induction machine. It is also possible to use a rotor having such a structure.

According to the electric motor having such a configuration, the first
No power needs to be supplied to the first rotor and the second rotor. Only coils wound on a fixed stator need to be supplied with power. Therefore, in the electric motor of the present invention, a slip ring for supplying power is not required, and the durability is greatly improved.

Here, it is preferable that the coil is concentratedly wound around a core provided in the stator. There are various winding methods for the coils of the stator, and a distributed winding in which the coils are wound over a plurality of cores is also possible. Of the various winding methods, so-called concentrated winding has the advantage that the manufacture of the stator becomes very easy. In other words, the stator can be formed by first winding the coil independently on each core, and thereafter arranging and fixing the core around which the coil is wound circumferentially.

In the above invention, various structures can be considered as structures that can be employed for the first rotor and the second rotor. For example, as a first mode of the electric motor of the present invention, the one rotor may include permanent magnets arranged radially.

In such an electric motor, if a rotating magnetic field is generated by, for example, a stator, a rotor having a permanent magnet rotates as a synchronous machine according to the magnetic field. In order to achieve such a function, the permanent magnet can be arranged on the rotor by various known methods. For example, the permanent magnet may be attached to the outer peripheral surface of the rotor, or a permanent magnet may be inserted into a hole provided in the circumferential direction near the outer peripheral surface. Among the various possible arrangements, as listed in the above invention,
If the permanent magnets are arranged radially, there is an advantage that the lines of magnetic force penetrating through the rotor can be effectively used, and the motor can be operated efficiently. Note that the term “radial” means that the permanent magnets are arranged so that the radial length is longer than the circumferential length.

According to a second aspect of the present invention, the other rotor may be a rotor having a structure capable of forming the stator and the winding type induction machine. Also,
The other rotor may be a rotor having a structure capable of forming the cage and the cage induction machine.

When the above structure is applied to the other rotor, when a rotating magnetic field is generated in the stator, this rotor rotates as an induction machine. In addition, since it can function as an induction machine even with the above-mentioned "one rotor", for example, if this one rotor is rotated by an external force, the other rotor of the present invention can be rotated accordingly. As a result, even when a current cannot be supplied to the stator due to a failure or other reasons, there is an advantage that the other rotor can be rotated according to the rotation of one rotor.

According to a third aspect of the electric motor of the present invention, the other rotor is the first rotor, and further inside the first rotor is not restricted by the first rotor by switching. It is also possible to provide a permanent magnet capable of taking either a rotatable state or a state rotatable integrally with the first rotor.

According to the electric motor having such a configuration, the first
Can be rotated in the state of both the induction machine and the synchronous machine. If the above-mentioned permanent magnet is made to be rotatable without being restricted by the first rotor, the first rotor functions as an induction machine with the stator. On the other hand, if the permanent magnet is made rotatable integrally with the first rotor, the first rotor functions as a synchronous machine with the stator.
When the first rotor functions as an induction machine, the rotation speed of the first rotor is lower than the rotation speed of the rotating magnetic field due to its nature. According to the above configuration, since the first rotor can also function as a synchronous machine, it can rotate at the same speed as the rotating magnetic field.

When the second rotor is a rotor having a permanent magnet, a similar effect can be obtained between the second rotor and the second rotor. That is, when the second rotor is rotated by an external force or the like, by causing the first rotor to function as an induction machine, the first rotor can be rotated at a lower rotation speed than the second rotor. On the other hand, by causing the first rotor to function as a synchronous machine, it can be rotated at the same speed as the second rotor. Therefore, when the second rotor is connected to the input shaft and the first rotor is connected to the output shaft, and the electric motor of the present invention is used as a power transmission device,
There is an advantage that the rotatable range of the output shaft can be widened.

Further, as the electric motor of the present invention, both the first rotor and the second rotor may be rotors provided with permanent magnets.

In the electric motor having such a configuration, when a rotating magnetic field is generated in the stator, the first rotor and the second rotor can be rotated as a synchronous machine. Also,
For example, when the first rotor is rotated by an external force, the second rotor also rotates due to magnetic coupling between the first rotor and the second rotor. The rotation speeds of the two are basically the same, but by controlling the magnetic field generated in the stator, it is also possible to make the rotation speed relatively slip between the two.

As the electric motor of the present invention, the first rotor includes two rotors each having a permanent magnet-provided rotor arranged in series in the direction of the rotation axis. It can be characterized in that it can be changed in the circumferential direction of the rotating shaft.

According to the electric motor having such a configuration, the strength of the magnetic coupling between the first rotor and the stator is changed by changing the positional relationship between the two rotors (hereinafter referred to as pitch). be able to. For convenience of description, the two rotors will be referred to as rotor A and rotor B. For example, consider the case where the rotor A faces the coils of the stator. At this time, a very strong magnetic coupling is obtained between the rotor A and the stator. At this time,
If the pitch between the rotors A and B is adjusted so that the rotor B also faces the stator, very strong magnetic coupling can be obtained between the rotor B and the stator. Therefore, at this time, the strongest magnetic coupling is obtained between the first rotor and the stator. If the pitch of the rotor B is changed from this state, the coupling between the rotor B and the stator is weakened. Therefore, the coupling between the first rotor and the stator is also weakened. As described above, according to the above invention, the strength of the magnetic coupling between the first rotor and the stator can be changed, and the power output from the first rotor can be changed. Naturally, the power output from the first rotor can also be controlled by controlling the magnetic field with the stator. Therefore, according to the electric motor of the present invention, the power output from the first rotor can be controlled in a wide range by using both the control of the pitch of the first rotor and the control of the magnetic circuit.

In the above invention, the inner rotor may be provided with three or more rotors. This makes it possible to control the power output from the first rotor in a wider range.

In the electric motor of the present invention, one of the first rotor and the second rotor has a permanent magnet, and the stator and the one rotor have a structure forming a vernier motor. You can also.

The operation of the present invention will be described by taking a case where the first rotor corresponds to the one rotor as an example. The vernier motor is a type of synchronous motor. However, the relationship between the number of salient poles of the stator around which the coil is wound and the number of permanent magnets provided on the first rotor is different from that of a normal synchronous motor. Is what you have. In a normal synchronous motor, a relationship of “number of salient poles / number of phases = number of permanent magnets / 2” is established. For example, when the number of salient poles is 12 in a synchronous motor using three-phase alternating current of U, V, and W phases, the number of salient poles / 3 = 4, and four salient poles are provided for each phase. become. On the other hand, if eight permanent magnets are alternately arranged with N and S magnetic poles appearing on the outer peripheral surface, the number of magnets having N poles on the outer peripheral surface is the number of permanent magnets / 2 = 4. Therefore, one U through which the U-phase current flows
When one N pole faces the phase coil, the remaining U phase coil also faces the N pole. By maintaining such a relationship, the motor can be rotated most efficiently. However, on the other hand, the pulsation of torque, mainly due to the phase change of the current that generates the magnetic field,
That is, there is a characteristic that cogging torque is easily generated.

In the vernier motor, the number of salient poles and the number of permanent magnets are set so that the above-mentioned relationship, that is, "number of salient poles / number of phases = number of permanent magnets / 2" is not established. Specifically, when three-phase alternating current is used, “the number of salient poles / the number of phases = the number of permanent magnets / 2 ± 1”. With such a setting, it is possible to avoid a state where all the U-phase coils and the N pole face each other at once. The same applies to coils of other phases. Therefore, during the rotation of the first rotor, there is an advantage that the interaction of the magnetic field between the stator and the first rotor can be averaged, and the torque fluctuation during the rotation can be reduced. According to the above-described invention, the variation in the output torque of the first rotor can be reduced by employing a structure in which the stator and the first rotor form a vernier motor having such characteristics. The same applies to the case where the second rotor corresponds to one rotor in the above-described invention.

In this electric motor, the other rotor, which is different from the one rotor, has a structure capable of forming a winding type induction machine, and the winding efficiently removes magnetic flux from the one rotor and the stator. It is desirable to be wound so as to be able to interlink.

The operation efficiency of the motor can be improved by winding the coil of the other rotor so that the magnetic flux from the one rotor can be efficiently linked. Since this winding method changes depending on the number of magnetic poles of the one rotor, the number of cores of the stator, and the like, it is determined experimentally or analytically.

The following power transmission device can be configured as a device using the electric motors of various forms described above. The power transmission device of the present invention includes an input shaft and an output shaft provided coaxially, a motor coupled to both, and control means for controlling operation of the motor, and receives power from the input shaft. A power transmission device capable of outputting power from the output shaft, wherein the electric motor is concentrically formed around the rotation shaft, the first rotor being connected to the input shaft, and being connected to the output shaft. And a single stator, and a magnetic circuit passing through all of the first rotor, the second rotor, and the stator can be formed, and the stator flows a current. A motor that is wound with windings that can affect the strength of the magnetic circuit by controlling the current flowing through the windings of the stator; The said And summarized in that a means for controlling the magnetic coupling between the rotor.

According to this power transmission device, the degree of magnetic coupling between the input shaft and the output shaft is controlled by controlling the strength and the like of the magnetic circuit passing through all of the first rotor, the second rotor, and the stator. To adjust. As a result, the power input at a certain rotational speed and torque from the input shaft can be output from the output shaft after the torque is converted to a different rotational speed and torque from that at the time of input.

The operation described above is the same as the operation realized by using a combination of the clutch motor CM and the assist motor AM as shown in FIG. 55 as the prior art, for example. ADVANTAGE OF THE INVENTION According to the power transmission device of this invention, there exists an advantage which can implement | achieve the same effect | action while keeping the size of an apparatus smaller than before.

In the conventional power transmission device, a part of mechanical power is extracted as electric power by the clutch motor CM.
By supplying this electric power to the assist motor AM,
Torque conversion was realized. If a part of mechanical power is converted to electric power, or conversely, electric power is converted to mechanical power, a certain amount of energy loss occurs in each conversion. On the other hand, the power transmission device of the present invention controls a magnetic coupling between a magnetic element coupled to the input shaft and a magnetic element coupled to the output shaft, thereby converting a part of power to electric power. The torque can be directly converted and output. Therefore, it is possible to eliminate the loss that occurs when converting between mechanical power and electric power, and it is possible to transmit power efficiently.

Various arrangements are possible for the arrangement of the rotor and the stator and the state of connection with the input shaft and the output shaft in the power transmission device. Specifically, from inside the rotating shaft, “rotor, rotor, stator”, “rotor,
Three types of configurations, "stator, rotor," and "stator, rotor, rotor" are possible. In each configuration, any of the inner rotor and the outer rotor may be used as the input shaft and any of the rotors may be used as the output shaft. Of course,
In one operating state, the rotating shaft connected to the inner rotor corresponds to the input shaft, and in another operating state, the rotating shaft corresponds to the output shaft. This includes those in which the axes to be replaced are replaced.

The above-described power transmission device can be operated in various modes by the function of the control means. For example, the control means controls a current flowing through a winding of the stator, thereby controlling the first rotor and the second rotor.
Means for interrupting the magnetic circuit between the rotors.

According to the power transmission device having such control means, it is possible to prevent the power input from the input shaft from being transmitted to the output shaft. If the power transmission device is replaced with a mechanical clutch and described, the above function corresponds to a released state of the clutch. Various methods can be considered as a method of interrupting the magnetic circuit between the first rotor and the second rotor. For example, a current that generates a magnetic field having the same strength and an opposite direction to the magnetic field generated between the first rotor and the second rotor in a state where no current is flowing through the stator winding flows through the stator winding. There is a way. It is also possible to change the path of the magnetic circuit formed between the first rotor and the second rotor by passing a current through the windings of the stator so that a magnetic circuit is not formed between the two. is there.

According to another aspect of the present invention, the control unit controls the current flowing through the windings of the stator so that the positive power is transmitted between the stator and the second rotor. It may be a means for generating torque.

According to such a power transmission device, power can be output from the output shaft even when there is no input of power from the input shaft. In other words, this corresponds to a so-called power running operation in which the magnetic element coupled to the output shaft and the stator are ordinary motors. Of course, when power is input from the input shaft, it is also possible to apply additional torque and output from the output shaft.

According to another aspect of the present invention, the control means includes means for controlling a part of the power input from the input shaft to a magnetic element which is not coupled to either the input shaft or the output shaft. It may be a means for regenerating the electric power via the output shaft and transmitting the remaining power to the output shaft.

According to such a power transmission device, while the power input from the input shaft is torque-converted and transmitted to the output shaft,
Part of it can be regenerated as electric power. The regenerated power may be stored in power storage means such as a battery, or may be used for driving another device.

Further, in the power transmission apparatus of the present invention, the power transmission apparatus further includes a detecting means for detecting a difference between the number of rotations of the input shaft and the output shaft, and the motor includes an outer rotor having a first rotor provided with a permanent magnet. The second rotor is an inner rotor capable of forming a cage induction machine with the stator, and further inside the inner rotor, is rotatable without being restricted by the inner rotor, and integrally with the inner rotor. An electric motor including a permanent magnet that can take any of a rotatable state, wherein the control means, in addition to the control, when an absolute value of a difference between the number of rotations detected by the detection means is equal to or less than a predetermined value. In some cases, the means may be a means for making a permanent magnet provided inside the inner rotor rotatable integrally with the inner rotor.

According to the power transmission device having such a configuration, the range in which torque can be converted from the input shaft to the output shaft can be increased by controlling the rotation state of the permanent magnet provided inside the inner rotor. That is, if the permanent magnet provided inside the inner rotor is made to be rotatable without being restricted by the inner rotor, the inner rotor becomes a state forming an outer rotor and an induction machine. Therefore, at this time, the inner rotor rotates at a lower rotation speed than the outer rotor. On the other hand, if the permanent magnet provided inside the inner rotor is made rotatable integrally with the inner rotor, the inner rotor is in a state where a magnetic coupling is formed with the outer rotor provided with the permanent magnet. Therefore, the inner rotor can rotate at the same rotation speed as the outer rotor. As described above, according to the power transmission device, the power input from the input shaft can be torque-converted in a wide range and output from the output shaft.

Further, in the power transmission device of the present invention, a rotor having a permanent magnet is connected in series in the direction of the input shaft and the output shaft as an inner rotor located inside the first rotor or the second rotor. An electric motor having two rotors arranged therein, wherein a positional relationship between the two rotors can be changed in a circumferential direction of the input shaft and the output shaft, and the control device performs the control in the control. In addition, according to the magnitude of the torque input from the input shaft,
The means for changing the positional relationship between the two rotors so that the strength of the magnetic coupling between the inner rotor and the stator changes.

The power transmission device of the present invention uses the electric motor of the fifth embodiment described above. As described above, the fifth motor transmits a signal from the input shaft to the output shaft by controlling the pitch of the two rotors provided as the inner rotor and controlling the magnetic coupling between the inner rotor and the outer rotor. Power can be varied over a wide range. Therefore, according to the power transmission device having the configuration using such an electric motor, it is possible to torque-convert the power input from the input shaft in a wide range and transmit the torque to the output shaft.

Further, in the power transmission device of the present invention, one of the first rotor and the second rotor of the electric motor is a wound-type rotor having windings wound thereon, and is wound around the wound-type rotor. It is also possible to provide a rotor control device that controls an interaction between a magnetic field generated in the wound rotor and the magnetic circuit by controlling a current flowing through the turned winding.

According to this power transmission device, in addition to controlling the magnetic coupling between the first rotor and the second rotor by the control device, the first rotor or the second rotor is controlled by the rotor control device. It is possible to control the interaction between the magnetic field generated in the wound rotor constituting one of the rotors and the magnetic circuit. Therefore, according to the power transmission device,
When the degree of freedom for controlling the magnetic coupling and interaction between the first rotor, the stator, and the second rotor is increased, for example, when a wound-type rotor functions as a rotor of an induction machine,
It is possible to control the current flowing through the wound rotor so as to suppress the loss caused by slip. As a result, the power transmission device can be operated in an operation state with a higher power factor and efficiency. Further, the wound-type rotor having the wound windings can function not only as a rotor of the induction machine but also as a synchronous motor controlled by a rotor control device with the stator. For this reason, according to the power transmission device, the rotation speed of the electric motor can be controlled in a wide range, and, for example, the winding type rotor can be rotated at a higher rotation speed than the other rotor.

The electric motor and the power transmission device described above can be applied to various devices, but can be applied to a hybrid vehicle as shown below as an example. A hybrid vehicle according to the present invention includes a prime mover and a power transmission device according to the present invention coupled to a drive shaft having a rotating shaft and wheels of the prime mover, and is a hybrid vehicle that can travel with power output from at least the prime mover. is there.

An example of the configuration of a conventional hybrid vehicle has been described with reference to FIG. In such a hybrid vehicle, the clutch motor CM and the assist motor AM
Were used as power transmission devices. In contrast,
In the hybrid vehicle of the present invention, the above-described electric motor or power transmission device of the present invention is applied. As a result,
The hybrid vehicle of the present invention can obtain the various effects already described for the electric motor and the power transmission device of the present invention. Specifically, since the power transmission device can be downsized, the size of the power output device including the prime mover can be downsized. In general, in a vehicle, space restrictions for mounting a power output device are severe, so that the merit of downsizing the device is very large.

Further, in the above hybrid vehicle, the efficiency of the power transmission device can be improved, so that the driving efficiency of the entire vehicle can be improved. Originally, a hybrid vehicle is characterized by being excellent in fuel efficiency, but according to the hybrid vehicle of the present invention, the characteristics can be further improved.

It should be noted that the electric motor and the power transmission device of the present invention can be applied not only to a hybrid vehicle but also to a power output device in combination with a prime mover and to be used as a power source for various devices. . For example, application to various transport machines such as trains, machine tools, and the like can be considered.
In this case, an internal combustion engine, an electric motor, or the like can be used as the prime mover.

[0062]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below based on examples. (1) Configuration of Motor as First Embodiment: FIGS. 1 and 2 show the configuration of a motor as a first embodiment of the present invention.
FIG. 1 is a cross-sectional view in a cross section orthogonal to the rotation axis,
FIG. 2 is a cross-sectional view in a cross section along a rotation axis.
As shown in FIG. 1, the electric motor 100 according to the first embodiment has an inner rotor 110, a stator 140, and an outer rotor 170 arranged concentrically around an inner rotor shaft 102 from the inside. In FIG. 1, illustration of the wound coil is omitted. As shown in FIG. 2, the outer rotor 170 is connected to the outer rotor shaft 104.
The inner rotor shaft 102, the stator 140, and the outer rotor shaft 104 are relatively rotatably coupled to each other via bearings 106 to 108.

The structure of each of the inner rotor 110, the stator 140, and the outer rotor 170 of the electric motor 100 will be described. 3 to 5 are cross-sectional views of the inner rotor 110, the stator 140, and the outer rotor 170 in cross sections orthogonal to the rotation axis. 6 to 8 show the inner rotor 11 in a cross section in a direction along the rotation axis.
FIG. 3 is a cross-sectional view of a stator 0, an outer rotor 170, and a stator 140; First, the inner rotor 110 will be described with reference to FIGS.
Next, the configuration of the stator 140 will be described with reference to FIGS. 4 and 7, and finally, the configuration of the outer rotor 170 will be described with reference to FIGS.

The inner rotor 110 is, as shown in FIG.
It is mainly composed of an inner rotor core 112 and a permanent magnet 114. As shown in FIG. 3, the inner rotor core 112 includes eight substantially fan-shaped portions. The inner rotor core 112 is formed by laminating a plate-shaped inner rotor core formed by punching a thin sheet of non-oriented electrical steel sheet in the direction of the inner rotor shaft 102 as shown in FIG. An insulating layer is formed on the surface of the plate-shaped inner rotor core. After the plate-shaped inner rotor cores are laminated, they are radially arranged at equal intervals in the aluminum case 118. Note that an adhesive layer is formed on the surface of the plate-shaped inner rotor core 112, the plate-shaped inner rotor cores 112 are laminated and pressed against each other, and then the adhesive layer is heated and melted, temporarily fixed, and then aluminum It may be arranged in the case.

Between the eight inner rotor cores 112,
As shown in FIG. 3, eight permanent magnets 114 are radially arranged. The permanent magnets 114 are arranged such that their magnetic poles face in the circumferential direction, and adjacent permanent magnets are arranged such that the same magnetic poles face each other. As shown in FIG. 3, the inner rotor core 112 has a cross-sectional shape that prevents the permanent magnet 114 from jumping out in the radial direction due to centrifugal force when the electric motor rotates. FIG. 9 is a perspective view showing the arrangement of the inner rotor core 112 and the permanent magnets. After disposing the inner rotor core 112 and the permanent magnets 114 in the aluminum case 118 in this manner, the entire body is fixed by the fixing lid 116 with the aluminum lid 120. Next, the inner rotor shaft 102 is pressed into the center of the aluminum case 118 and fixed with the bolts 122 to complete the inner rotor 110.

The reason why the permanent magnets 114 are radially arranged is that the magnetic flux of the permanent magnets can be effectively used by this arrangement, and the operating efficiency and torque of the motor can be increased. As a structure of the rotor, a structure in which a permanent magnet is attached to the outer peripheral surface of the rotor, a structure in which a permanent magnet is inserted into a hole provided in the circumferential direction near the outer periphery, and the like are known. These configurations can be adopted as the configuration of the inner rotor 110.

Next, the configuration of the stator 140 will be described. The stator 140 is mainly composed of a stator core 142 and a coil 144, as shown in FIG. As shown in FIG. 4, the stator core 142 has a cross section in which only the teeth of a normal stator for winding a coil around the teeth are made independent, that is, a portion located on the inner peripheral side and the outer peripheral side based on a substantially rectangular shape. And 12 independent parts having a cross-section with some flanges. As shown in FIG. 7, the stator core 142 is formed by laminating a plate-shaped stator core formed by punching a thin sheet of non-oriented electrical steel sheet in the rotation axis direction. An insulating layer is formed on the surface of the plate-shaped stator core. After the plate-shaped stator cores are laminated, fixing bolts 146 are provided.
Is fixed by The plate-like inner rotor core 112
An adhesive layer is formed on the surface of the substrate, the plate-like inner rotor cores 112 are laminated and pressed against each other, and then the adhesive layer is heated and melted, temporarily fixed, and further fixed with fixing bolts 146. It does not matter.

The coils 144 are wound around the twelve stator cores 142, respectively. In FIG. 4, a state in which the coil 144 is wound is shown only for a part of the stator core 142, and the coil of the remaining stator core 142 is omitted. The coil 144 is wound by so-called concentrated winding, and is wound around each stator core 142 independently. FIG. 10 is a perspective view showing a state where the coil 144 is wound around the stator core 142. Adopting the concentrated winding in this way has an advantage that the manufacture of the stator core 142 becomes very easy. Of course, a distributed winding in which a coil is wound over a plurality of stator cores 142 may be employed. The electric motor according to the present embodiment is driven by flowing three-phase alternating current of U, V, and W phases through the stator 140. Therefore, as shown in FIG. 4, every third coil 144 located in the circumferential direction is connected as a coil through which a current having the same phase flows. These coils 144 can be connected to an external power supply.

The stator core 142 around which the coil 144 is wound is arranged circumferentially as shown in FIG. At this time, aluminum flanges 147 and 148 are used to determine the position of each stator core 142. Pins 149 used for positioning each stator core 142 are circumferentially arranged at equal intervals on the flanges 147 and 148. The arrangement shown in FIG. 4 is realized by sandwiching each stator core 142 between the flanges 147 and 148 using these pins 149 as guides. In this state, since the flanges 147 and 148 are separable, a jig for temporarily fixing the flanges 147 and 148 and the stator core 142 is used.

In this state, the outer peripheral surface and the inner peripheral surface between the stator cores 142 are fixed by a resin mold. FIG. 11 shows a perspective view of the stator core 142. The portion painted black in FIG. 11 is the resin mold 150. FIG.
In FIG. 1, the flanges 147 and 148 are not shown,
The stator core 142 is also fixed to the flanges 147 and 148 by the resin mold 150. Thus, the stator 140 of this embodiment is completed.

In the stator 140 of this embodiment, as shown in FIG. 11, the member connecting the stator core 142 in the circumferential direction is only the resin mold 150. As a structure of a stator that has been conventionally used, a stator 1 shown in FIG.
As shown by reference numeral 410, it was constituted by a ring-shaped yoke portion and salient pole portions. As described above, the stator 1 according to the present embodiment has a structure having no yoke.
40 has a structure completely different from the conventional stator. By adopting such a structure, as described later, the magnetic flux passing through the stator core 142 cannot escape in the circumferential direction. That is, the magnetic flux passes through the stator core 142 in the radial direction. By such an operation, the electric motor of the present embodiment can obtain various effects described later.

The stator 140 of this embodiment is such that the space between the stator cores 142 is filled with the resin mold 150 and the stator core 142 is fixed in the circumferential direction. It does not matter. Stator core 142
If each stator core 142 can be fixed,
There may be a gap between them. In this embodiment, the resin mold 150 is employed because of the ease of manufacture and the
0 stiffness and heat resistance to heat from the coil 144;
This is because heat dissipation and the like are considered.

Finally, the structure of the outer rotor 170 will be described. As shown in FIG. 5, the outer rotor 170 mainly includes an outer rotor core 172 and a coil 174. The outer rotor core 172 is formed by punching a thin sheet of non-oriented electrical steel sheet into a ring-shaped cross section having 72 slots on the inside as shown in FIG. It is formed by doing. An insulating layer is formed on the surface of the plate-shaped outer rotor core. After the plate-shaped outer rotor cores are laminated, they are press-fitted into an aluminum case 176 and caulked and fixed by a circular fixing ring 178. An adhesive layer was formed on the surface of the plate-like outer rotor core, and the plate-like outer rotor cores were laminated and pressed against each other. It may be inserted.

The coil 174 is wound between the slots of the outer rotor core 172. FIG. 12 shows a method of winding a coil in this embodiment. For convenience of explanation, FIG.
As shown in FIG.
Numbers are given in a clockwise order from the number. The coils are wound sequentially between every nine slots. That is, after being wound between the 0th slot and the 9th slot, it is wound between the 9th slot and the 17th slot. Similarly, a coil is wound between each slot. The coil 174 of the outer rotor 172 is not connected to an external power supply. The outer rotor 172 is a rotor that functions as an induction machine with the stator 140 or the inner rotor 110 as described later. The coil 174 can be wound by various methods. In the present embodiment, the coil 174 is wound so as to effectively intersect with the magnetic flux from the stator 140. The case 176 of the outer rotor 170 assembled in this way is
As shown in FIG. 7, the outer rotor shaft 104 is press-fitted to the flange 177 with bolts.

The motor 100 according to the first embodiment is completed by assembling the inner rotor 110, the stator 140, and the outer rotor 170 having the above-described configurations via the bearings 106 to 108 in the arrangement shown in FIG. Although not shown in FIG. 1 and FIG.
Can be mounted on various devices by fixing the stator 140 to a case or the like. Of course, the inner rotor shaft 102 and the outer rotor shaft 104 may be assembled to the device via a bearing.

(2) Structure of the motor control device:
A configuration of a power transmission device using the electric motor 100 according to the embodiment will be described. FIG. 13 is a block diagram illustrating a schematic configuration of the power transmission device 10 according to the first embodiment. The power transmission device 10 includes the electric motor 10 according to the first embodiment described above.
0, an ECU 12 for controlling its operation, a sensor unit for detecting information necessary for the control, and an electric motor 10.
It is composed of a drive circuit 20 for applying a voltage required for the operation of a zero and a battery 30 as a power supply.

As shown in the figure, the ECU 12 is a microcomputer having a control CPU 13, a ROM 14, a RAM 15 and the like therein. Execute This ECU 1
2 inputs information necessary for control via an input port 17 and outputs a control signal via an output port 18. Further, a torque command value required for controlling the electric motor 100 can be externally input to the input port 17.

The signal input to the ECU 12 as information necessary for control includes a current value flowing through each phase of the electric motor 100. As described above, the motor 100 of the first embodiment applies three-phase AC of U, V, and W phases to the coil 14 of the stator 140.
4 is operated. Of this three-phase exchange,
A current sensor 2 for detecting a current value in the U phase and the V phase
2, 23 are provided. These current sensors 22,
After the high-frequency component is removed by the filters 24 and 25 from the current value detected by the filter 23, the current value is converted into a digital signal by the ADCs 26 and 27 and input to the ECU 12. The reason that the current sensors 22 and 23 are provided only for the U-phase and the V-phase is that the three-phase alternating current flows under the condition that the sum of the currents of the U-phase, the V-phase and the W-phase becomes zero. This is because if the V-phase current value can be detected, the W-phase current can be obtained by calculation. Of course, a current sensor may be provided in the W phase.

The ECU 12 is connected to the drive circuit 20 via the output port 18 by four signal lines. U phase,
Gate signal G for controlling the current of each phase of V phase and W phase
These are three lines for outputting u, Gv, and Gw, and a line for outputting a signal SD for shutting down all currents. The ECU 12 controls the operation of the drive circuit 20 and the electric motor 100 by outputting a high or low signal to these signal lines.

The drive circuit 20 is electrically connected to the battery 12 and the motor 100 in addition to the ECU 12. The drive circuit 20 uses the battery 30 as a power source,
Is a circuit for flowing current to each of the U, V, and W phases. FIG. 14 shows the configuration of the drive circuit 20. Drive circuit 20
Are configured as a transistor inverter as shown in FIG. The transistor on the source side (T in FIG. 14)
u +, Tv +, Tw +) and transistors on the sink side (Tu−, Tv−, Tw− in FIG. 14) are provided as a set of two for each of the U, V, and W phases of the electric motor 100. The source side is connected to the plus side of the battery 30, and the sink side is connected to the minus side of the battery 30.
Each transistor has a diode called a flywheel diode (Du +, Du−, Dv in FIG. 14).
+, Dv-, Dw +, Dw-) are connected in series.

As described above, this drive circuit 20
It is electrically connected to the CU 12 by four signal lines. E
From the CU 12 to the drive circuit 20, signals Gu and G for controlling the switching of the U, V and W phase transistors.
v and Gw are output. As shown in FIG. 14, for example, the signal Gu is branched into two, and each of them is delayed by a delay circuit Dly.
+, Dly− and AND gates Ag +, Ag− are input as gate signals to the transistors Tu +, Tu−. Since the signal transmitted to the sink-side transistor Tu− is inverted by the inverter Inv on the way, the signal G
When a high or low signal is input as u, the transistors Tu + and Tu− are exclusively turned on / off. The same configuration applies to the V phase and the W phase. When a low signal is output from the ECU 12 to the shut-down signal SD, all outputs through the AND gates Ag +, Ag−, and the like become low. No current will flow.

Although FIG. 13 shows only a portion related to the control of the electric motor 100, other sensors or switches may be connected to the ECU 12 depending on the device on which the power transmission device 10 is mounted. . The torque command value may be input from outside as shown in the ECU 12, or may be set by calculation in the ECU 12 based on information from various sensors.

The electric motor 100 has the inner rotor shaft 102 and the outer rotor shaft 104 as rotating shafts as described above. The power transmission device 10 according to the present embodiment having the configuration described above converts the power input from one of the two rotation shafts provided in the electric motor 100 into the rotation speed and the rotation speed based on the operation principle and control described later. The torque can be converted and output to the other. Also, power can be output from one or both of the two rotating shafts without inputting power. Further, power input from one or both of the two rotating shafts can be regenerated as electric power.

(3) Principle of Operation of Power Transmission Device: The operation principle of the power transmission device described above will be described.
FIG. 15 shows an electric motor 100 used in a power transmission device.
FIG. 4 is an explanatory view showing the operation principle of FIG. Similar to FIG. 1, a cross-sectional view in a cross section orthogonal to the inner rotor shaft 102 is shown.
In FIG. 15, for convenience of explanation of the operation principle, the outer rotor 1
70 are shown with a radial interval between the stator 140 and the inner rotor 110.

As described above, the electric motor 10 of this embodiment is
The zero stator 140 has a structure without a yoke. Therefore, in the electric motor 100 of the present embodiment, the inner rotor 110
The magnetic flux generated by the permanent magnet 114 provided in the inner rotor core 112 is radially curved by the inner rotor core 112 as shown in FIG.
It passes through the stator 140 and reaches the outer rotor 170. After reaching the outer rotor 170, a magnetic circuit is formed which is bent in the circumferential direction and penetrates through the stator 140 again and returns to the inner rotor 110, as shown by the broken line in FIG. For comparison, FIG. 16 shows a conventional configuration, that is, a magnetic circuit in the case where a yoke exists in the stator. As shown in the figure, when a yoke is present, the magnetic flux emitted from the inner rotor 110a reaches the stator, is bent in the circumferential direction along the yoke of the stator 140a, and returns to the inner rotor 110a without reaching the outer rotor 170a.

As shown in FIG. 16, the inner rotor 11
When a magnetic circuit from 0 to the outer rotor 170 is not formed, no induced electromotive force is generated in the outer rotor 170 even when the inner rotor 110 is rotated. Therefore,
Power cannot be transmitted from the inner rotor 110 to the outer rotor 170. On the other hand, in the electric motor 100 of the present embodiment, a magnetic circuit from the inner rotor 110 to the outer rotor 170 is formed as shown in FIG. When the inner rotor 110 is rotated by an external force in this state, an induced electromotive force is generated in the outer rotor 170 according to a change in the magnetic circuit. When an induced electromotive force is generated, a magnetic field is generated in the outer rotor 170, and the outer rotor 170 is rotated by the interaction between the magnetic field and the magnetic field generated by the inner rotor 110. That is, the electric motor 100 of the present embodiment can constitute a kind of induction machine between the inner rotor 110 and the outer rotor 170. As a result,
When power is input from the inner rotor shaft 102, the power can be transmitted to the outer rotor shaft 104. At this time, based on the properties of the induction machine, the outer rotor shaft 104 rotates while sliding with respect to the inner rotor shaft 102. That is, “the rotation speed of the outer rotor shaft 104 <the rotation speed of the inner rotor shaft 102”. These effects can be obtained even when no current is flowing through the coil 144 of the stator 140.

In the electric motor 100 of this embodiment, the transmission of power can be controlled by controlling the magnetic circuit from the inner rotor 110 to the outer rotor 170 based on the above-described principle of power transmission. The principle of this power transmission control will be described. FIG. 17 is an explanatory diagram showing a state of the magnetic circuit when the coil 144 of the stator 140 is energized. In FIG. 17, the electric motor 10 of this embodiment is
Part of 0 is shown enlarged. Coil 1 of stator 140
By energizing 44, various magnetic fields can be generated in the stator. For example, it is also possible to generate a magnetic field in a direction opposite to the magnetic field from the inner rotor 110 to the outer rotor 170. FIG. 17 shows a state in which such a magnetic field in the opposite direction is generated. At this time, as a result of the superposition of the magnetic field of the inner rotor 110 and the magnetic field of the coil 144 on the outer rotor 170, FIG.
7, a magnetic field indicated by a white arrow is generated. That is, a weak magnetic field reaches the outer rotor 170 as compared with the state before the coil 144 is energized.

Generally, in an induction machine, the outer rotor 17
The torque output from 0 changes according to the strength of the magnetic field in the air gap between the outer rotor 170 and the stator 140 and the relative slip amount between the inner rotor 110 and the outer rotor 170. FIG. 18 shows the relationship between the torque output from the induction machine, the slip amount, and the strength of the magnetic field in the air gap. As illustrated, if the slip amount is constant, the output torque increases as the magnetic field in the air gap increases. Further, when the magnetic field in the air gap gradually increases the constant slip amount, the torque increases in accordance with the slip amount until a certain slip amount is reached. The torque becomes maximum at a certain slip amount, and the torque gradually decreases at a certain slip amount. Usually, the induction machine is used with a slip amount equal to or less than the slip amount at which the torque is maximized.

In this embodiment, as described above, the stator 14
By energizing the zero coil 144, the strength of the magnetic field in the air gap between the outer rotor 170 and the stator 140 can be changed. If the magnetic field in the air gap is weakened by energizing the coil 144 as shown in FIG. 17, the transmitted torque can be made smaller than in the state before energization based on the principle of the induction machine described above. If the transmitted torque is constant, that is, if the load applied to the outer rotor shaft 104 is constant, the amount of slip between the inner rotor shaft 102 and the outer rotor shaft 104 can be increased. This is because the outer rotor shaft 1 is
04 can be rotated at a lower speed.

FIG. 19 shows such power transmission.
As shown in FIG. 19, the power of each rotating shaft can be represented by any one of the rotating points in a plane in which the horizontal axis represents the rotation speed and the vertical axis represents the torque. Generally, power, that is, energy per unit time is represented by rotation speed × torque. Accordingly, various rotation points correspond to the rotation at which the magnitude of the power is constant. Curves P1, P2, P shown in FIG.
3 is a curve connecting the rotation points where the magnitude of the power is constant.

It is assumed that the rotation state of the outer rotor shaft 104 when the coil 144 of the stator 140 is not energized is represented by a rotation point DP1 in FIG. That is, it is assumed that the rotation speed is N1 and the torque is T1. At this time, the load torque T1 applied to the outer rotor shaft 104
With the outer rotor 170 and the stator 140 kept constant.
If the magnetic field in the air gap is weakened, the outer rotor shaft 104 shifts to a lower rotation point, that is, a rotation point DP2 (rotation speed N2, torque T1) in FIG. As a result, the power P2 (N2 × T1) lower than the power P1 (N1 × T1) before energization from the outer rotor shaft 104.
1) will be output. Note that the rotation state of the outer rotor shaft 104 at the time of energization can take not only the rotation point DP2 but also a state corresponding to various rotation points on the curve P2 according to the load.

By controlling the amount of current supplied to the coil 144 of the stator 140, the inner rotor 110
It is also possible to interrupt the magnetic circuit up to 70. Such a state is shown in FIG. FIG. 20 shows the inner rotor 11.
This figure shows a state in which a magnetic field having the same strength and opposite direction to the magnetic field from 0 to the outer rotor 170 is generated in the stator 140. In this case, since the magnetic field generated by the inner rotor 110 and the magnetic field generated by the stator 140 cancel each other, no magnetic field from the inner rotor 110 to the outer rotor 170 is formed. Even if the inner rotor 110 is rotated in this state, the outer rotor 170 does not rotate. Electric motor 10 of the present embodiment
In the case of 0, by controlling the strength of the magnetic field generated in the stator 140 in this way, it functions as a clutch between the inner rotor shaft 102 and the outer rotor shaft 104 and can realize a state in which the clutch is released. The rotation state of the outer rotor shaft 104 at this time corresponds to the origin O in FIG.

On the other hand, the outer rotor 170 is
An induction machine is also configured between zero. Therefore, if the inner rotor 110 is made unrotatable and the coil 144 of the stator 140 is energized to generate a rotating magnetic field, the outer rotor 170 rotates according to the rotating magnetic field. By controlling the strength and the rotation speed of the rotating magnetic field, the outer rotor 170 can be rotated at a desired torque and rotation speed as an induction machine. Generally, in induction machines, coil 1
The current flowing through 44 is controlled based on two components of the current for generating torque by the interaction between the current for generating an induced electromotive force in outer rotor 170 and the magnetic field generated by the induced electromotive force. The former is called an exciting current, and the latter is called a torque current. After setting the magnitudes of the exciting current and the torque current in accordance with the torque command value, the current flows through each phase so that the magnetic field rotates in accordance with the rotation speed command value. Details of such control are well-known as control of an induction machine, and thus description thereof is omitted here.

The control of the current of the stator 140 described with reference to FIGS. 17 and 20 is a type of control of the exciting current and the torque current. In the case of a general induction machine, since the inner rotor 110 does not exist, the current value is
The setting is made in consideration of only the magnetic field generated by the inner rotor 11.
The difference is that the current value is set so that the operation can be performed with high efficiency and high power factor in consideration of the magnetic field due to zero.

In FIG. 17, it has been described that, by controlling the excitation current and the torque current, for example, the power input from the inner rotor 110 can be transmitted to the outer rotor 170 with a large slip amount. That is, it has been described that power can be output with the same torque and a lower rotation speed than the rotation speed and the torque of the outer rotor shaft 104 before the coil 144 is energized. At this time, FIG.
As shown in FIG. 5, the power output from the outer rotor shaft 104 is lower than the power P1 (N1 × T1) before energization.
2 (N2 × T2). As shown below, in the state of FIG. 17, the power of this difference is regenerated from the coil 144 of the stator 140 as electric power.

In FIG. 17, it has been described above that a current is applied to the coil 144 to generate a magnetic field in a direction opposite to the magnetic field generated by the inner rotor 110. Actually, this energization is realized as a current based on the induced electromotive force generated in the coil 144 by the rotation of the inner rotor 110. When a magnetic field is generated in the coil 144 in the direction shown in FIG.
At 44, an induced electromotive force is generated which allows a current for generating a magnetic field in the opposite direction to flow. The magnetic field generated by this electromotive force is nothing but the opposite magnetic field shown in FIG. Therefore, FIG.
In the state of 7, the electric motor 100 corresponds to a state in which the electric motor 100 is regenerating part of the power input from the inner rotor shaft 102 as electric power and outputting the remaining power from the outer rotor shaft 104.

In the state where the reverse exciting current shown in FIG. 17 is flowing, by further applying a positive torque current to the coil 144, the torque output from the outer rotor shaft 104 can be increased according to the magnitude. it can. By appropriately setting the torque current, it is possible to output a power equal to the power P1 before energization from the outer rotor shaft 104. An exciting current flows so as to generate the magnetic field shown in FIG.
When the outer rotor shaft 104 is rotating at a lower rotation speed N2 than before the energization and the magnitudes of the powers are equal, the rotation state of the outer rotor shaft 104 shifts to a rotation point DP3 shown in FIG. As a result, a torque larger than the rotation point DP1 before energization is output.

When power equal to power P1 before energization is output from outer rotor shaft 104, no energy is transferred between stators 140, as is apparent from the energy balance. The exciting current is the inner rotor 110
It has been described above that the current is generated by the induced electromotive force accompanying the rotation of the. When a torque current is supplied to the coil 144 so that the power of the inner rotor shaft 102 and the power of the outer rotor shaft 104 become equal, the power regenerated by the rotation of the inner rotor 110 is consumed as the power for transmitting the torque current, and the coils are balanced. The current flows through 144. This corresponds to a state in which reflux occurs inside the U-phase, V-phase, and W-phase of the coil 144, and there is no exchange of power with the battery 30.

An example of the reflux is shown by an arrow in FIG. As shown, the current passing through the U-phase source side transistor Tu + flows into the U-phase coil, and flows out of the V-phase and W-phase. Since an induced electromotive force is generated in each coil, the potential increases during this time. As a result, the currents flowing out of the V-phase and W-phase coils pass through the flywheel diodes Dv + and Dw + provided on the respective source sides, and return to the U-phase source-side transistor Tu +. That is, current flows without passing through the battery 30. This is an example of reflux. However, this is only an ideal case with no energy loss. In reality, energy loss occurs due to the impedance of the coil 144, the on-resistance of the transistor, and the like, so that the power is supplied from the battery 30.

If a larger positive torque current is applied, a larger power than the rotation point DP1 before energization, for example, as shown in FIG.
It is also possible to output a power corresponding to the rotation point DP4 in FIG. In such a case, the inner rotor shaft 1
This corresponds to a state in which torque is assisted using the electric power of the battery 30 with respect to the motive power input from 02 and then output from the outer rotor shaft 104. Of course, the outer rotor shaft 104 can rotate at various points other than the rotation point DP4.

Thus, in the electric motor 100 of the present embodiment, by controlling the excitation current and the torque current, the power input from the inner rotor shaft 102 can be converted into various rotation speeds and torques and output from the outer rotor shaft 104. It is possible. In the above description of the operation principle, a description has been given by capturing a certain static state of the inner rotor 110 and the outer rotor 170. However, since both are actually rotating,
The magnetic field generated in the stator 140 is also controlled so as to rotate according to the rotational speeds of the two. In the above description of the operation principle, the case where the inner rotor shaft 102 serves as the power input shaft has been described as an example.
A similar effect can be achieved even when the power input shaft is a power input shaft.

According to the electric motor 100 described above, the inner rotor 110, the stator 140, and the outer rotor 170 are arranged coaxially, so that the inner rotor shaft 10
An electric motor capable of controlling the rotation state of both the outer rotor shaft 104 and the outer rotor shaft 104 can be formed in a small size.
Further, by employing so-called concentrated winding for the stator 140, the electric motor 100 can be easily manufactured.

The electric motor 100 according to the present embodiment also has an advantage that only one drive circuit 20 for controlling the rotation state of the inner rotor shaft 102 and the outer rotor shaft 104 is required. Since the number of drive circuits 20 can be reduced, the size of the device can be further reduced, and the cost of the device can be reduced. As described above, this drive circuit is a circuit for controlling the current flowing through the coil 144 of the stator 140. In the electric motor 100 of the present embodiment, it is not necessary to supply electric power to the inner rotor 110 and the outer rotor 170. Therefore, it is not necessary to use a slip ring or the like when supplying power. As a result,
The electric motor 100 of the present embodiment is an electric motor having extremely excellent durability.

In the motor 100 of this embodiment, the inner rotor 110, the stator 140, and the outer rotor 17
By arranging in the order of 0, there is also an advantage that the rotation of the inner rotor 110 and the outer rotor 170 can be easily controlled. For example, when the stator 140 is disposed on the outermost or innermost side, if the rotation of the inner rotor 110 is controlled, the reaction appears on the outer rotor 170, and it is difficult to appropriately control the torque of both. In the electric motor 100 of the present embodiment, by taking the above-described arrangement, the inner rotor 110 or the outer rotor 17 is provided.
Since the reaction at the time of controlling the rotation of zero can be absorbed by the stator 140, the control of these rotations is facilitated. In addition, such an arrangement has an advantage that the distance between the stator 140 and the inner rotor 110 and the outer rotor 170 is reduced, so that a large amount of energy is not required for controlling both of them.

In the above description, the power transmission device 10 using the electric motor 100 of the present embodiment has been proposed. According to the power transmission device 10 of the present embodiment, the power input from the inner rotor shaft 102 can be converted into various rotation speeds and torques and output from the outer rotor shaft 104. In addition, power can be output from the outer rotor shaft 104 regardless of the input of power from the inner rotor shaft 102.
Further, the power input from the inner rotor shaft 102 can be regenerated as electric power. These functions are achieved by a power transmission device combining a clutch motor CM and an assist motor AM described in the related art (see FIG. 55).
This is the same operation as. According to the power transmission device 10 of the present embodiment, such an operation can be realized by a small device.

In the power transmission device shown in FIG. 55 as a prior art, a process in which a part of mechanical power is once converted into electric power in the clutch motor CM and then converted again into mechanical power in the assist motor AM is performed. After that, torque conversion is realized. The conversion between mechanical power and electric power usually causes some loss. In contrast,
In the power transmission device 10 of the present embodiment, the two inner rotors 1 are driven by the current flowing through the coil 144 of the stator 140.
The transfer of magnetic energy between the outer rotor shaft 104 and the outer rotor 170 and the stator 140 is directly controlled.
Can be converted to a desired rotation speed and torque. Therefore, the power transmission device 10 of the present embodiment
Can torque-convert the power input from the inner rotor shaft 102 and output the torque from the outer rotor shaft 104 efficiently.

In the motor 100 of this embodiment, an induction motor is constituted by the inner rotor 110 having permanent magnets and the outer rotor 170 having windings. In such an electric motor 100, even when the coil 144 of the stator 140 is not energized, the outer rotor 170 rotates with the rotation of the inner rotor 110. Therefore, the power transmission device 10 according to the present embodiment to which the electric motor 100 is applied has the coil 144 due to the failure of the drive circuit 20 or the battery 30 or the like.
Even when power cannot be supplied to the inner rotor shaft 102,
Can transmit power to the outer rotor shaft 104.

(4) Motor and Power Transmission Device as Second Embodiment: Next, the configuration of the motor and power transmission device as the second embodiment will be described. FIGS. 21 and 22 show the configuration of an electric motor according to a second embodiment of the present invention. FIG.
FIG. 2 is a cross-sectional view in a cross section orthogonal to the rotation axis.
2 is a cross-sectional view in a cross section along a rotation axis. As shown in FIG. 21, the electric motor 200 of the second embodiment has an inner rotor 210, a stator 240, and an outer rotor 270 arranged concentrically around an inner rotor shaft 202 from the inside. In FIG. 21, illustration of the wound coil is omitted. As shown in FIG. 22, outer rotor 270 is coupled to outer rotor shaft 204.
The inner rotor shaft 202, the stator 140, and the outer rotor shaft 204 are relatively rotatably coupled to each other via bearings 206 to 208.

The structure of each of the inner rotor 210, the stator 240, and the outer rotor 270 of the electric motor 200 will be described. 23 to 25 show the inner rotor 210 and the stator 24 in cross sections orthogonal to the rotation axis, respectively.
0 is a sectional view of the outer rotor 270. 26 to 2
8 is a cross-sectional view of the inner rotor 210, the stator 240, and the outer rotor 270 in a cross section in a direction along the rotation axis. First, the configuration of the inner rotor 210 will be described with reference to FIGS.
7, the structure of the stator 240 will be described.
The configuration of the outer rotor 270 will be described with reference to FIG.

As shown in FIG. 23, the inner rotor 210 is roughly composed of an inner rotor core 212 and a permanent magnet 214.
It is composed of The inner rotor core 212 is shown in FIG.
Has a ring-shaped cross section as shown in FIG. The inner rotor core 212 is formed by laminating a plate-shaped inner rotor core formed by punching a thin non-oriented electrical steel sheet in the direction of the inner rotor shaft 202 as shown in FIG. An insulating layer is formed on the surface of the plate-shaped inner rotor core. After the plate-shaped inner rotor core is laminated,
The inner rotor shaft 202 is press-fitted and fixed with bolts 216. Note that an adhesive layer is formed on the surface of the plate-like inner rotor core 212, the plate-like inner rotor cores are laminated and pressed against each other, and then the adhesive layer is heated and melted, fixed temporarily, and then fixed to the inner rotor shaft. 202 may be press-fitted.

As shown in FIG. 23, 16 permanent magnets 214 are attached to the outer peripheral surface of the inner rotor core 212. The permanent magnets 214 are arranged such that the magnetic poles face in the radial direction, and are arranged such that the N pole and the S pole alternately appear on the outer peripheral surface. In the second embodiment, the permanent magnet 21
4, the permanent magnet may be included in the inner rotor 210 as described in the first embodiment. Further, a permanent magnet may be inserted into a hole provided in the circumferential direction near the outer periphery.

The structure of the stator 240 is almost the same as the structure of the stator 140 described in the first embodiment. The stator 140 in the first embodiment has 12 stator cores 1.
, The stator 24 of the second embodiment is provided.
0 is different in that it has 18 stator cores 242. The coil 244 is concentratedly wound around the stator core 242. The stator cores 242 and the flanges 247 and 248 are fixed by resin molding.
The stator 240 of the present embodiment is also the same as the stator 14 of the first embodiment.
Like the case of No. 0, it has a structure without a yoke.

As shown in FIG. 25, the outer rotor 270 is roughly composed of an outer rotor core 272 and a permanent magnet 274.
It is composed of The outer rotor core 272 has a ring-shaped cross section as shown in FIG. Further, it is formed by laminating thin sheets of non-oriented electrical steel sheets. A permanent magnet 274 is attached to the inner peripheral surface of the outer rotor core 272. The permanent magnets 274 are arranged such that the magnetic poles face in the radial direction, and are arranged such that N poles and S poles alternately appear on the inner peripheral surface. The outer rotor 270 is fixed by a bolt 278 and a flange 277 into which the outer rotor shaft 204 is press-fitted.

As described above, in the motor of the second embodiment, the permanent magnets 214 and 274 are attached to the inner rotor 210 and the outer rotor 270. The numbers of the permanent magnets 214 and 274 attached to both are equal. The number of permanent magnets 214 and 217 can be set freely according to the number of stator cores 242. However, it is desirable that the number of permanent magnets provided in the inner rotor 210 and the outer rotor 270 be the same for the reason described later.

The electric motor 200 according to the second embodiment is completed by assembling the inner rotor 210, the stator 240, and the outer rotor 270 having the above-described configurations via the bearings 206 to 208 in the arrangement shown in FIG. Although not shown in FIGS. 21 and 22, the electric motor 200 can be mounted on various devices by fixing the stator 240 to a case or the like. Of course, the inner rotor shaft 202 and the outer rotor shaft 204 may be assembled to the device via a bearing.

In the power transmission device 10 of the first embodiment,
If the motor 100 is replaced with the motor 200 of the second embodiment, a power transmission device can be configured. The hardware configuration other than the electric motor is the same as that of the first embodiment. The operation principle of such a power transmission device will be described.

Also in the electric motor 200 of the second embodiment, since a structure without a yoke is applied as the stator 240, a magnetic circuit extending from the inner rotor 210 through the stator 240 to the outer rotor 270 is formed. First
In the electric motor 100 of the embodiment, the inner rotor 110 and the outer rotor 170 constitute an induction machine. On the other hand, in the electric motor 200 of the second embodiment, the inner rotor 11
0 and the outer rotor 170 form a magnetic coupling that rotates integrally by magnetic coupling. That is, when the coil 244 of the stator 240 is not energized, the inner rotor shaft 202 and the outer rotor shaft 204 rotate without slippage. In this embodiment, the inner rotor 2
10 and permanent magnet 21 attached to outer rotor 270
The reason for matching the numbers of 4,274 is that the strongest magnetic coupling is obtained between the inner rotor 210 and the outer rotor 270 in such a case.

When the coil 244 of the stator 240 is energized, the intensity of the magnetic field from the inner rotor 210 to the outer rotor 270 can be controlled. Therefore, similarly to the electric motor 100 of the first embodiment, the magnitude of the power output to the outer rotor shaft 204 with respect to the power input from the inner rotor shaft 202 can be controlled. At this time, unlike the electric motor 100 of the first embodiment, the inner rotor 210 and the outer rotor 270 rotate in a state where no slip occurs.
Is weakened, power is transmitted to the outer rotor shaft 204 with a correspondingly lower torque.

Further, the energized state of the coil 244 can be controlled to cut off the magnetic field from the inner rotor 210 to the outer rotor 270. In this case, the power transmission device will function as a solved clutch.
As described above in the first embodiment, such a case corresponds to a state in which all of the power input from the inner rotor shaft 202 is regenerated as electric power.

On the other hand, the stator 240 and the outer rotor 27
0 configures a synchronous machine. That is, when the coil 244 of the stator 240 is energized to generate a rotating magnetic field, the outer rotor 270 rotates according to the rotation of the magnetic field. In the synchronous machine, as in the control of the induction machine described in the first embodiment, the magnitude of the current flowing through the coil 244 is determined based on the two components. If the inner rotor 210 is fixed to be unrotatable and a current is supplied to the coil 244 based on the torque and the command value of the rotation speed, the outer rotor 2
70 runs at a desired rotational speed and torque.

A current for regenerating the power of the inner rotor 210 and a current for powering the outer rotor 270 at a desired torque and rotation speed are superimposed on the stator
If the current flows through the zero coil 244, the power from the inner rotor 210 can be converted into torque and output from the outer rotor 270. If the power input from the inner rotor 210 and the power output from the outer rotor 270 are equal, the torque can be converted without transmitting and receiving the power from the battery 30. If there is a difference between the two, Electric power corresponding to the difference is exchanged with the battery 30.

According to the electric motor 200 and the power transmission device described above, substantially the same effects as those of the electric motor 100 of the first embodiment can be obtained. In the first embodiment, the outer rotor 27 is rotated at a lower rotational speed with respect to the inner rotor 110.
Although the state where 0 rotates is the basic state, in the second embodiment, the state where the inner rotor 210 and the outer rotor 270 rotate at the same rotational speed is the basic operation state. Therefore, the electric motor 200 and the power transmission device of the second embodiment are suitable when the difference between the rotation speeds of the inner rotor shaft 202 and the outer rotor shaft 204 is relatively small.

(5) Motor and Power Transmission Device as Third Embodiment: Next, the configuration of the motor 300 and the power transmission device as the third embodiment will be described. FIG. 29 shows a configuration of an electric motor 300 according to a third embodiment of the present invention. FIG.
Is a cross-sectional view in a cross section orthogonal to the rotation axis. The configuration in the cross section in the direction along the rotation axis is substantially the same as that of the electric motors of the first embodiment and the second embodiment, and therefore the description thereof is omitted. As shown in FIG. 29, in the electric motor 300 of the third embodiment, an inner rotor 310, a stator 340, and an outer rotor 370 are arranged concentrically around an inner rotor shaft 302 from the inside. Similarly to the electric motors of the first and second embodiments, the outer rotor 370 is connected to the outer rotor shaft. The inner rotor shaft 302, the stator 320, and the outer rotor shaft 304 are relatively rotatably coupled to each other via bearings.

The structure of each of the inner rotor 310, the stator 340, and the outer rotor 370 of the electric motor 300 will be described. 30 to 32 show the inner rotor 310 and the stator 34 in cross sections orthogonal to the rotation axis, respectively.
0 is a sectional view of the outer rotor 370. FIG. 33
3 schematically shows a cross-sectional view of a cross section of the inner rotor 310 in a direction along the inner rotor shaft 302.

As shown in FIG. 30, the inner rotor 310 is composed of a cage rotor used for a so-called cage induction machine and a permanent magnet 316 located inside the cage rotor. The cage rotor includes an inner rotor core 312 and a rotor bar 314. Inner rotor core 31
Numeral 2 has a ring-shaped cross section as shown in FIG. 30, and is formed by laminating thin sheets of non-oriented electrical steel sheets. Rotor bar 314 is a copper bar, and is embedded in a groove formed on the outer peripheral surface of inner rotor core 312. In addition, the rotor bar 314 is joined at its ends by a ring-shaped short-circuit plate. An insulating layer is formed on the surface of the rotor bar 314.

As shown in FIG. 30, eight permanent magnets 316 are provided inside the cage rotor. The permanent magnet 316 is attached to the outer peripheral surface of a second inner rotor core 318 different from the inner rotor core 312. The permanent magnets 316 are arranged such that the magnetic poles face in the radial direction, and are arranged such that N poles and S poles alternately appear on the outer peripheral surface.

The second inner rotor core 318 to which the permanent magnet 316 is attached is rotatable without being restricted by the inner rotor 310. Further, as shown in FIG. 33, by coupling with a clutch disk 306 provided on the inner rotor shaft 302 by a clutch 308, both can be rotated integrally.

The structure of the stator 340 is almost the same as the structure of the stator 140 described in the first embodiment. The stator 140 in the first embodiment has 12 stator cores 1.
31, the stator 240 of the third embodiment is different in that it has 24 stator cores 342 as shown in FIG. 31. In the first embodiment, the coil 14
4 differs from the third embodiment in that the coils 344 are distributed and wound in the third embodiment. The stator cores 342 and the flange are fixed by a resin mold. Like the stator 140 of the first embodiment, the stator 340 of this embodiment has a structure without a yoke. Of course, in the stator 340 of this embodiment, the coil 344 may be wound by concentrated winding as in the first embodiment.

As shown in FIG. 32, the outer rotor 370 is roughly composed of an outer rotor core 372 and a permanent magnet 374.
It is composed of The outer rotor core 372 has a ring-shaped cross section as shown in FIG. Further, it is formed by laminating thin sheets of non-oriented electrical steel sheets. A permanent magnet 374 is attached to the inner peripheral surface of the outer rotor core 372. The permanent magnets 374 are arranged such that the magnetic poles face in the radial direction, and are arranged such that the N pole and the S pole alternately appear on the inner peripheral surface. Outer rotor 370 is fixed to the outer rotor shaft.

The motor 300 of the third embodiment is completed by assembling the inner rotor 310, the stator 340, and the outer rotor 370 having the above-described configurations via bearings. Although not shown in FIG. 29, the electric motor 300 can be mounted on various devices by fixing the stator 340 to a case or the like. Of course, the inner rotor shaft 302 and the outer rotor shaft may be assembled to the device via a bearing.

In the power transmission device 10 of the first embodiment,
If the motor 100 is replaced with the motor 300 of the third embodiment, the power transmission device 10A can be configured. FIG. 34 shows the configuration of this power transmission device 10A. Although the hardware configuration other than the electric motor is almost the same as that of the first embodiment,
The power transmission device 10A of the third embodiment further includes an inner rotor shaft speed sensor 303 for detecting the speed of the inner rotor shaft 302 and an outer rotor shaft speed sensor 305 for detecting the speed of the outer rotor shaft 304. As described later, the inner rotor shaft 302 and the outer rotor shaft 3
The permanent magnet 316 and the inner rotor 3
This is for controlling the connection with the number 10. Various sensors can be applied as the rotation speed sensor, and the rotation speed sensor may be calculated by calculation or the like without using the sensor. The operation principle of the power transmission device 10A will be described.

Also in the electric motor 300 of the third embodiment, since a structure without a yoke is applied as the stator 340, a magnetic circuit extending from the inner rotor 310 to the outer rotor 370 through the stator 340 is formed. First
In the electric motor 100 of the embodiment, the inner rotor 310 and the outer rotor 370 constitute an induction machine. In the third embodiment, the permanent magnet 316 provided in the inner rotor 310
If it is not restrained by the inner rotor 310, a cage-type induction machine can be configured with the outer rotor 370. However, considering that the permanent magnet is arranged on the inner rotor 110 in the electric motor 100 of the first embodiment and the outer rotor 170 is a winding-type rotor, the arrangement is reversed in the electric motor 300 of the third embodiment. Is equivalent to

On the other hand, if the second inner rotor provided with the permanent magnet 316 is switched to a state in which it can be rotated integrally with the inner rotor 310, similar to the electric motor 200 of the second embodiment,
The inner rotor 310 and the outer rotor 370 form a magnetic coupling. That is, the electric motor 30 of the third embodiment
At 0, by switching the coupling state between the permanent magnet 316 and the inner rotor 310, the same operation as the motor of the first embodiment can be performed, and the same operation as the motor of the second embodiment can be performed. .

The principle of controlling the magnetic field from the inner rotor 310 to the outer rotor 370 by energizing the coil 344 of the stator 340 and controlling the rotation of both of them is as follows.
This is the same as the power transmission devices of the first and second embodiments. Therefore, detailed description is omitted here. In the third embodiment, since the switching of the coupling state between the permanent magnet 316 and the inner rotor 310 is characteristic, such control will be described.

FIG. 35 is a flowchart showing the control of the switching of the coupling in the inner rotor 310. This process is a process that is periodically executed by the CPU 13 in the ECU 12. When this process starts, C
The PU 13 reads the rotation speed Nin of the inner rotor shaft 302 and the rotation speed Nout of the outer rotor shaft 304 (Steps S100 and S102). The rotation speeds of both are detected by rotation speed sensors 303 and 305, respectively. Next, the rotation speed Nin of the inner rotor shaft is compared with the rotation speed Nout of the outer rotor shaft (step S10).
4). When the rotation speed Nin of the inner rotor shaft is smaller than the rotation speed Nout of the outer rotor shaft, the clutch 30
8 is executed (step S108). If the rotation speed Nin of the inner rotor shaft is equal to or higher than the rotation speed of the outer rotor shaft, a process for engaging the clutch 308 is executed (step S110).

As described above, if the permanent magnet 316 is made to be rotatable without being restrained by the inner rotor 310, the electric motor 300 of the third embodiment becomes the electric motor 1 of the first embodiment.
Has the same effect as 00. The basic state of the electric motor 100 according to the first embodiment is such that the outer rotor 170 rotates at a lower rotational speed than the inner rotor 110. Therefore, in the power transmission device of the third embodiment, the “inner rotor shaft 302
Rotation speed Nin <rotation speed Nou of outer rotor shaft 304
t ”, the permanent magnet 316 is attached to the inner rotor 3
The state is switched to a rotatable state without being restricted by 10.

On the other hand, the permanent magnet 316 is
The motor 300 according to the third embodiment has the same effect as the motor 200 according to the second embodiment if the motor 300 is rotatable integrally with the motor 0. The electric motor 200 according to the second embodiment has an inner rotor 21.
0 and the outer rotor 270 rotated at the same rotation speed were the basic states. Therefore, in the power transmission device of the third embodiment, when the rotation speed Nin of the inner rotor shaft 302 and the rotation speed Nout of the outer rotor shaft 304 are substantially equal, the two are switched to a state in which they can be integrally rotated. In the flowchart of FIG. 35, the inner rotor shaft 30
2 is the rotation number No of the outer rotor shaft 304.
Although it is illustrated that the clutch release process is always performed when the rotation speed is smaller than “out”, in actuality, the “inner rotor shaft 30
2 rotation speed Nin <rotation speed No of outer rotor shaft 304
"ut", the clutch 308 can be engaged when both of them reach substantially the same rotational speed.

It is desirable to provide a certain hysteresis for the switching in order to avoid frequent switching due to fluctuations in the number of rotations of the inner rotor shaft 302 and the outer rotor shaft 304. According to the power transmission device of the third embodiment described above, power can be appropriately transmitted in a wider range than the power transmission devices of the first embodiment and the second embodiment.

(6) Motor and Power Transmission Device as Fourth Embodiment: Next, the configuration of the motor and power transmission device as the fourth embodiment will be described. FIGS. 36 and 37 show a configuration of a motor as a fourth embodiment of the present invention. FIG.
FIG. 3 is a sectional view taken along a section perpendicular to the rotation axis, and FIG.
FIG. 7 is a cross-sectional view in a cross section along a rotation axis. As shown in FIG. 36, in the electric motor 400 of the fourth embodiment, an inner rotor 410, a stator 440, and an outer rotor 470 are arranged concentrically around an inner rotor shaft 402 from the inside. Although not shown in FIG. 37, the outer rotor 470 is connected to the outer rotor shaft. Inner rotor shaft 402, stator 440, outer rotor shaft 4
04 are mutually rotatably connected via a bearing.

The respective structures of the inner rotor 410, the stator 440, and the outer rotor 470 of the electric motor 400 will be described. 38 to 40 show the inner rotor 410 and the stator 44 in a cross section orthogonal to the rotation axis, respectively.
0 is a sectional view of an outer rotor 470.

As shown in FIG. 37, two inner rotors 410 are arranged in series in the direction of the inner rotor shaft 402.
It is composed of two rotors 410A and 410B. As shown in FIG. 38, each of the inner rotors 410A and 410B roughly includes an inner rotor core 412 and a permanent magnet 41.
And 4. Its configuration is the motor 2 of the second embodiment.
00 is the same as the inner rotor 210. That is, FIG.
Sixteen permanent magnets 414 are attached to the outer peripheral surface of the inner rotor core 412 having the cross section shown in FIG. The permanent magnets 214 are arranged such that the magnetic poles face in the radial direction, and are arranged such that the N pole and the S pole alternately appear on the outer peripheral surface.

Both inner rotors 410A and 410B are connected to inner rotor shaft 402. In both cases, the positional relationship in the rotation direction (hereinafter, referred to as pitch) can be changed. This positional relationship can be changed even during the operation of the electric motor 400. In FIG. 38 (a), both rotors 410
A, about the permanent magnet 414 provided in 410B, the state where the corresponding permanent magnets match when seen from the front is shown. In FIG. 38B, the rotor 41 located at the rear is
OB is relatively rotated with respect to the rotor 410A, and the corresponding permanent magnets are in a shifted position.
In this embodiment, the inner rotors 410A, 410
The positional relationship of B can be changed. The range in which the positional relationship between the two can be changed is a range corresponding to the rotation of the magnet at the position of No. 0 in the rotor 410B to the position of No. 1 in FIG.

Referring to FIG. 37, inner rotor 410A,
A mechanism for changing the pitch of 410B will be described. The inner rotor shaft 402 is provided with a thread-shaped groove in a portion connected to the inner peripheral surface of the inner rotor 410B as shown by a broken line OL in FIG. A groove that matches this groove OL is also formed on the inner peripheral surface of the inner rotor 410B. An actuator 406 is coupled to the inner rotor 410B, and can be moved in the SLD direction shown in FIG. 37, that is, in the axial direction of the inner rotor shaft 402 by hydraulic pressure. When the inner rotor 410B is moved in the axial direction SLD by the actuator 406, the inner rotor 410B relatively rotates in the circumferential direction of the inner rotor shaft 402 with the movement in the SLD direction due to the action of the groove OL described above. At this time, the inner rotor 410A is
02, the pitch of the inner rotors 410A and 410B changes. As the pitch changing mechanism, various mechanisms other than such a mechanism may be employed, such as providing a motor for rotating the inner rotor 410B in the circumferential direction of the inner rotor shaft 402. Note that the actuator 406 of this embodiment is
Is electrically connected to the ECU 12, and controls the movement of the inner rotor 410B in the SLD direction by a control signal from the ECU 12, thereby changing the rotor pitch.

As shown in FIG. 37, the stator 440 has a stator core 442 corresponding to the rotors 410A and 410B.
A, 442B, coils 444A, 444B, and guide portions 446A, 446B. Stator core 4
42A and 442B are each composed of twelve portions having a cross section shown in FIG. As shown in FIG. 37, these stator cores 442A and 442B are formed by laminating plate-shaped stator cores formed by punching out thin sheets of non-oriented electrical steel sheets in the rotation axis direction. In addition, each of the stator cores 442A and 442B has
The coils 444A and 444B are wound.

The stator cores 442A, 442B
Are arranged in the circumferential direction, and the stator 140 of the first embodiment is
Similarly to the above, it is fixed by a resin mold. The outer periphery of the stator cores 442A and 442B is
Guide portions 446A and 446B for guiding the magnetic flux from A and 442B to the outer rotor 470 are coupled. The guide portions 446A and 446B are integrally formed of a non-oriented electrical steel sheet. In the direction along the rotation axis, it has a cross-sectional shape shown in FIG. 37, and in the direction orthogonal to the rotation axis, it has a rectangular cross-sectional shape as shown in FIG. Guide part 446A,
446B are alternately arranged on the circumference as shown in FIG. In FIG. 39, the guide portion 446B is indicated by a chain line. The structure of the stator 440 is shown in FIG. 41 in a perspective view. In FIG. 41, a hatched portion is a resin molded portion. The magnetic flux penetrating through the stator 440 slides in the direction of the inner rotor shaft 402 by passing through the guide portions 446A and 446B, and reaches the outer rotor 470. In that the stator 440 of the fourth embodiment also has no yoke, the electric motor 10 described above is used.
It is common to the 0, 200, and 300 stators.

As shown in FIG. 40, the outer rotor 270 is configured as a cage rotor that can form a cage induction machine with the stator 440. It is mainly composed of an outer rotor core 472 and a rotor bar 474. The outer rotor core 472 has a ring-shaped cross section as shown in FIG. Further, it is formed by laminating thin sheets of non-oriented electrical steel sheets. Outer rotor core 472
The rotor bar 474 is embedded in the inner peripheral surface of the.
Rotor bar 474 is a copper bar and the surface is insulated. Although not shown in FIGS. 37 and 40,
The rotor bars 474 are connected at their ends by a ring-shaped short-circuit plate. Outer rotor 470 is fixed to the outer rotor shaft. In the present embodiment, the outer rotor 470 is formed as a cage type rotor, but may be configured as a winding type rotor like the outer rotor 170 of the first embodiment.

The motor 400 according to the fourth embodiment is completed by assembling the inner rotor 410, the stator 440, and the outer rotor 470 having the above-described configurations via bearings in the arrangement shown in FIG. With this configuration, the electric motor 400 according to the fourth embodiment includes the stator 44
A squirrel-cage induction machine is constituted between the inner rotor 410 and the outer rotor 470. Although not shown in FIGS. 36 and 37, the electric motor 400 can be mounted on various devices by fixing the stator 440 to a case or the like. Of course, the inner rotor shaft 402
Alternatively, the outer rotor shaft 404 may be assembled to the device via a bearing.

In the power transmission device 10 of the first embodiment,
If the motor 100 is replaced with the motor 400 of the fourth embodiment, a power transmission device can be configured. The hardware configuration other than the electric motor is the same as that of the first embodiment. The operation principle of such a power transmission device will be described.

Also in the electric motor 400 of the fourth embodiment, since a structure without a yoke is applied as the stator 440, a magnetic circuit extending from the inner rotor 410 to the outer rotor 470 through the stator 440 is formed. 4th
In the electric motor 400 according to the embodiment, the electric motor 100 according to the first embodiment is used.
Similarly to the above, an induction machine is configured between the inner rotor 410 and the outer rotor 470. Further, by energizing the coil 444 of the stator 440, the strength of the magnetic field from the inner rotor 410 to the outer rotor 470 can be controlled. Therefore, the magnitude of the power output to the outer rotor shaft 404 with respect to the power input from the inner rotor shaft 402 can be controlled by the same control as that of the electric motor 100 of the first embodiment. The power input from the inner rotor shaft 402 is regenerated as electric power,
It is also possible to power 0.

On the other hand, in the electric motor of the fourth embodiment, the power transmitted from the inner rotor shaft 402 to the outer rotor shaft 404 by controlling the positional relationship between the inner rotors 410A and 410B without depending on the energization of the coil 444 of the stator 440. Can be controlled.

For example, when the rotor 410A is the stator 440
Let us consider a case where it faces one of the stator cores 442A. At this time, the rotor 410A and the stator core 442A
A very strong magnetic coupling is obtained between. At this time, if the pitch between the rotors 410A and 410B is adjusted so that the rotor 410B also faces the stator core 442B, very strong magnetic coupling can be obtained between the rotor 410B and the stator core 442B. Therefore,
At this time, the strongest magnetic coupling is obtained between the inner rotor 410 and the stator 440. If the pitch of the rotor 410B is changed from this state, the coupling between the rotor 410B and the stator core 442B is weakened. Therefore, the inner rotor 410 and the stator 440
Will also weaken.

As described above, in the electric motor 400 according to the fourth embodiment, the strength of the magnetic coupling between the inner rotor 410 and the stator 440 can be changed by changing the pitch between the inner rotors 410A and 410B.
If the strength of the magnetic coupling changes, the power output from the outer rotor 470 changes accordingly. Therefore, in the electric motor 400 of the fourth embodiment, it is possible to control the output power without depending on the control of energization of the coils 444A and 444B of the stator 440.

An example of the control of the pitch of the electric motor 400 in the fourth embodiment will be described. FIG. 42 is a flowchart showing the flow of the rotor pitch control process. This process is a process that is periodically executed by the CPU 13 in the ECU 12. When this process is started, the CPU 13 reads the required torque Td * (Step S200). Next, the torque change rate ΔT is calculated from the difference between the required torque Td * and the required torque when the rotor pitch control processing routine was executed last time (step S202).
Further, the pitches of the inner rotors 410A and 410B are read (step S204). This pitch can be calculated from the control signal of the actuator 406. Of course, a sensor for detecting the relative angle between the two may be provided.

When the rotor pitch is detected, the maximum torque Tmax that motor 400 can output at the pitch is detected.
And the minimum torque Tmin are determined. The reason why the range of torque that can be output varies according to the rotor pitch is as described above. The CPU 13 calculates the required torque Td *
Is determined to be larger than the maximum torque Tmax thus obtained (step S206). If it is larger, a rotor pitch setting process is executed so that the required torque Td * can be output by changing the rotor pitch. (Step S212). Required torque Td * is maximum torque Tm
If it is smaller than ax, it is determined whether the required torque Td * is smaller than the minimum torque Tmin (step S208). The required torque Td * is the minimum torque Tmi
If it is smaller than n, a rotor pitch setting process is executed to change the rotor pitch and output the required torque Td * (step S212).

If the required torque Td * is equal to or greater than the minimum torque Tmin, it is next determined whether or not the absolute value of the torque change rate ΔT is greater than a predetermined value α (step S).
210). If the torque change rate ΔT is larger than the predetermined value α, it is expected that the current rotor pitch is likely to be an inappropriate value with respect to the required torque Td *. Execute (Step S21)
2). In such a case, the reason why the rotor pitch setting process is performed is to make the control of the rotor pitch sufficiently follow a change in the required torque Td * because a change in the rotor pitch takes a little response time.

As a process for setting the rotor pitch, in this embodiment, a map for giving an appropriate rotor pitch to the required torque Td * is stored in the ROM 14 in the ECU 12 in advance, and the rotor pitch is set according to the required torque Td *. It is to be read from this map. In accordance with the rotor pitch set in this way, the ECU 12
When the control signal is sent to 6, the rotor pitch is changed by the operation described above.

In the electric motor 400 of the fourth embodiment, the power output to the outer rotor shaft 404 can be controlled by two means. Both can be used in parallel. Therefore, according to the electric motor 400 of the fourth embodiment, the power output from the outer rotor shaft 404 can be controlled in a wide range by using both in parallel. For example, in an operation state in which a large output torque is required, the pitch of the inner rotors 410A and 410B is adjusted to a position where the magnetic coupling with the stator 440 becomes the strongest, and then the energization of the coil 444 of the stator 440 is controlled. To control the output torque. On the other hand, in an operation state in which the required torque is relatively small, the stator 44
After adjusting the pitch to a position where the magnetic coupling with zero is weakened, the amount of current supplied to the coil 444 can be controlled to control the output torque. In this way, even when the range in which the power can be controlled by energizing the coil 444 is limited, it is possible to control the power over a wide range as the entire power transmission device.

(7) Motor and Power Transmission Device as Fifth Embodiment: Next, the configuration of a motor 500 and a power transmission device as a fifth embodiment will be described. FIG. 43 and FIG.
FIG. 4 shows a configuration of a motor 500 according to a fifth embodiment of the present invention. FIG. 43 is a cross-sectional view in a cross section orthogonal to the rotation axis, and FIG. 44 is a cross-sectional view in a direction along the rotation axis. As shown in FIG. 43, the electric motor 50 of the fifth embodiment
Reference numeral 0 denotes an inner rotor 510, a stator 540, and an outer rotor 570 that are arranged concentrically from the inner side around the inner rotor shaft 502. As shown in FIG. 44, outer rotor 570 is coupled to outer rotor shaft 504. The inner rotor shaft 502, the stator 540, and the outer rotor shaft 504 are relatively rotatably coupled to each other via bearings 506 to 508.

The structure of each of inner rotor 510, stator 540, and outer rotor 570 of electric motor 500 will be described. 45 to 47 show the inner rotor 510 and the stator 54 in a cross section orthogonal to the rotation axis, respectively.
0 is a sectional view of an outer rotor 570. 48 to 5
0 is a cross-sectional view of the inner rotor 510, the stator 540, and the outer rotor 570 in a cross section in a direction along the rotation axis. First, the configuration of the inner rotor 510 will be described with reference to FIGS.
9, the configuration of the stator 540 will be described.
The configuration of the outer rotor 570 will be described with reference to FIG.

The inner rotor 510 has the same configuration as the inner rotor 210 in the electric motor 200 of the second embodiment. That is, as shown in FIG. 45, the inner rotor core 512 is formed by attaching 16 permanent magnets 514 to the outer peripheral surface. The inner rotor core 512 has a ring-shaped cross section as shown in FIG. Inner rotor core 51
No. 2 is formed by laminating thin sheets of non-oriented electrical steel sheets. Further, the permanent magnets 514 attached to the outer peripheral surface are arranged such that the magnetic poles are oriented in the radial direction, and the N pole and the S pole alternately appear on the outer peripheral surface. In the fifth embodiment, the permanent magnet 514 is attached to the surface, but the permanent magnet may be included in the inner rotor 210 as described in the first embodiment. Further, a permanent magnet may be inserted into a hole provided in the circumferential direction near the outer periphery.

The structure of the stator 540 is the same as the structure of the stator 240 described in the second embodiment. That is, as shown in FIGS. 46 and 49, the eighteen stator cores 542 around which the coils 244 are concentratedly wound are arranged in a circumferential shape, and the respective stator cores 542 and the flanges 547, 548 are arranged.
Are fixed by a resin mold. The stator 540 of this embodiment also has a structure without a yoke, similarly to the stator in each of the embodiments described above. Therefore, it is possible to form a magnetic circuit extending from the inner rotor 510 to the outer rotor 570 through the stator 540.

The electric motor 500 according to the fifth embodiment has a structure in which the inner rotor 510 and the stator 540 described above form a vernier motor. The vernier motor is a type of synchronous machine, and includes the number of cores 542 of the stator 540 around which the coil 544 is wound, and the inner rotor 51.
This means that the relationship with the number of permanent magnets 514 provided in 0 is different from that of a normal synchronous machine. In a normal synchronous machine, a relationship of “number of cores / number of phases = number of permanent magnets / 2” is established. In the present embodiment, since the three-phase alternating current of the U, V, and W phases is used, “the number of phases = 3”. As described above, since the stator 540 of the fifth embodiment is provided with 18 stator cores 542, “the number of cores / 3 =
6 ", which means that six salient poles are provided for each phase. On the other hand, 16 permanent magnets are attached to the inner rotor 510 of the fifth embodiment. Therefore, the number of magnets in which the N pole appears on the outer peripheral surface is “the number of permanent magnets / 2 = 8”.

When the relationship of “number of cores / number of phases = number of permanent magnets / 2” holds, when one N pole faces one U-phase coil through which a U-phase current flows, the remaining U-phase coils And the N pole. Setting the number of cores and the like in this way has the advantage that a large torque can be output, and has the characteristic that torque pulsation, that is, cogging torque, is likely to occur mainly due to the change in the phase of the current that generates the magnetic field. On the other hand, the motor 50 of the fifth embodiment
At 0, this relationship does not hold, so that all U-phase coils and N poles do not face at once. The same applies to coils of other phases. Therefore, during the rotation of the inner rotor 510, the interaction of the magnetic field between the stator 540 and the inner rotor 510 can be averaged, and the cogging torque during the rotation can be reduced.

The outer rotor 570 is similar to that shown in FIGS.
As shown in FIG. 0, the outer rotor 170 of the first embodiment has almost the same configuration. That is, the configuration is a winding type rotor. The outer rotor 570 is configured by winding a coil 574 around a slot provided on the inner peripheral surface of an outer rotor core 572 having a ring-shaped cross section shown in FIG. The outer rotor core 572 is formed by laminating non-oriented electromagnetic steel sheets. The winding method of the coil 574 of the outer rotor 570 is shown in FIG. Fifth
The winding of the coil 574 in the embodiment is not as axially symmetric as the outer rotor 170 of the first embodiment (see FIG. 12). In the fifth embodiment, the inner rotor 510 and the stator 54
0 is due to the formation of the vernier motor. That is, the coil 574 of the outer rotor 570 is wound so that the magnetic flux emitted from the inner rotor 510 can be effectively linked in a situation where the permanent magnet 514 attached to the inner rotor 510 and the stator core 542 are not completely opposed. is there. FIG. 51 shows one winding method for the permanent magnet 514 and the stator core 542 in the fifth embodiment. The winding method of the coil 574 of the outer rotor 570 differs depending on the number of permanent magnets and the number of stator cores. It will be.

The motor 500 according to the fifth embodiment is completed by assembling the inner rotor 510, the stator 540, and the outer rotor 570 having the above-described configurations via the bearings 506 to 508 in the arrangement shown in FIG. Although not shown in FIGS. 43 and 44, the electric motor 500 can be mounted on various devices by fixing the stator 540 to a case or the like. Of course, the inner rotor shaft 502 and the outer rotor shaft 504 may be assembled to the device via a bearing.

In the power transmission device 10 of the first embodiment,
If the motor 100 is replaced with the motor 500 of the fifth embodiment, a power transmission device can be configured. The hardware configuration other than the electric motor is the same as that of the first embodiment. Also,
The electric motor 500 has the same configuration as the electric motor 100 of the first embodiment except that the inner rotor 510 and the stator 540 form a vernier motor, and can be controlled by the same method as the first embodiment. By configuring the vernier motor, the current value to be passed through the coil 544 of the stator 540 is different from that of the electric motor 100 of the first embodiment, but the control principle is the same.

Therefore, according to the electric motor 500 and the power transmission device described above, the same effects as those of the electric motor 100 and the power transmission device of the first embodiment can be obtained. In addition, since the inner rotor 510 and the stator 540 form a vernier motor, there is an advantage that the cogging torque between the two can be reduced.

(8) Sixth Embodiment: A power transmission device 10B according to a sixth embodiment will be described. FIG. 52 is an explanatory diagram showing a schematic configuration of the power transmission device 10B. The power transmission device 10B of the sixth embodiment is different from the power transmission device 10 of the first embodiment.
It is almost the same configuration as. The motor applied to the power transmission device 10B has substantially the same configuration as the motor 100 of the first embodiment. However, in the first embodiment, the outer rotor 17
The coil wound around 0 is closed so as to form a circuit by itself. On the other hand, the coil wound around the outer rotor 170 of the electric motor 100 according to the present embodiment is different in that the coil is wound so that a three-phase alternating current can be supplied from outside. Drive circuit 2
0 indicates that a three-phase alternating current flows through the electric motor 100 as in the case of the power transmission device 10 of the first embodiment. In FIG. 52, the electric wires between the drive circuit 20 and the electric motor 100 are collectively shown by a single line for convenience of illustration. The current flowing through the motor 100 is controlled by the current sensor 32,
U12 is captured as a signal that can be processed. Although the current sensor 32, the filter 34, and the ADC 36 are shown as one element for convenience of illustration, actually, like the power transmission device 10 of the first embodiment, there are sensors that handle U-phase and V-phase currents, respectively. They are provided in pairs. The drive circuit 20 is connected to the ECU 12, and four control signals for controlling switching of the drive circuit 20 can be input from the ECU 12. In FIG. 52, these control signals are collectively shown by one line for convenience of illustration.

In the sixth embodiment, a driving circuit 21 is further connected to the battery 30 and the electric motor 100 in addition to the above-described configuration. The drive circuit 21 is similar to the drive circuit 20,
This is a circuit for flowing a current to the electric motor 100, and is configured by a transistor inverter (see FIG. 14). Further, as the drive circuit 21 is added, a current sensor 33, a filter 35, and an ADC 37 are respectively added and connected to the input port 17 of the ECU 12. These elements are for taking in the electric current flowing through the electric motor 100 by the drive circuit 21 as a signal that the ECU 12 can process. Current sensor 33, filter 35, AD
Although C37 is shown as one element for the sake of illustration, actually, sensors and the like for handling U-phase and V-phase currents are provided as a pair. Further, the driving circuit 21
Are connected to the ECU 12 so that four control signals for controlling the switching of the drive circuit 21 can be input from the ECU 12. In FIG. 52, these control signals are collectively shown by one line for convenience of illustration.

FIG. 53 shows how the drive circuits 20, 21 and the motor 100 are connected. As shown, the drive circuit 20
Is connected to a coil wound around the stator 140 of the electric motor 100. The drive circuit 21 is connected to a coil wound around the outer rotor 170 of the electric motor 100. The energization of the outer rotor 170 is performed via the slip ring 40. Instead of the slip ring 40, a differential transformer or the like may be used.

Power transmission device 10B having such a configuration
By controlling the current by the drive circuit 20, the same function as the power transmission device 10 of the first embodiment can be achieved. In the power transmission device 10 of the first embodiment, the current generated in the winding of the outer rotor 170 is based on the induced electromotive force caused by the rotation of the inner rotor 110 and the like. In the power transmission device 10B of the seventh embodiment, in addition to the current based on the induced electromotive force, the outer rotor 1
An electric current can flow through 70. Therefore, the interaction between the magnetic field generated in the outer rotor 170 and the magnetic circuit formed from the inner rotor 110 through the stator 140 can be controlled with a high degree of freedom.

For example, by controlling the switching of the drive circuit 21, an induced current accompanying the rotation of the inner rotor 110 can flow through the coil of the outer rotor 170. At this time, the outer rotor 170 functions as a rotor of the induction machine. Generally, in an induction machine, loss occurs due to slippage of the outer rotor. Power transmission device 10B of the above embodiment
By controlling the current flowing through the outer rotor 170, the loss due to the slip can be suppressed.
Such control can be realized by various methods. In the present embodiment, the current value of each phase at which the loss is minimized according to the rotation speed and torque of the electric motor 100 is determined in advance by the R
The current is stored in the OM 14 as a map, and a current flows through the coil of the outer rotor 170 according to the map. By performing such control, the power transmission device 1
OB suppresses a loss due to slippage of the outer rotor 170, and allows the motor 100 to be operated with a high power factor and efficiency.

Further, the outer rotor 170 and the stator 14
A kind of synchronous motor can also be configured between 0 and 0.
Therefore, by controlling the current flowing through the outer rotor 170, the magnitude of the torque output from the outer rotor 170 can be controlled. Further, by supplying a current capable of outputting a positive torque to the outer rotor 170, the outer rotor 170 can be rotated at an increased speed. Accordingly, the power transmission device 10B can relatively easily realize the rotation of the outer rotor 170 at a higher rotation speed than the inner rotor 110. In the present embodiment, the above-described control is realized by storing a current flowing through the outer rotor 170 as a map in advance in the ROM 14 in accordance with the rotation speeds and torques of the outer rotor 170 and the inner rotor 110, and applying a current according to this map. This map is set in consideration of not only the magnetic field generated by the coil wound around the stator 140 but also the magnetic field generated by the inner rotor 110 and the induced electromotive force generated in the winding of the outer rotor 170 due to its rotation.

In the power transmission device of the sixth embodiment described above, a motor having substantially the same configuration as the motor 100 of the first embodiment is used. On the other hand, the motors of the various embodiments described above can be used instead of the motor 100. In the sixth embodiment, the outer rotor 170
However, when the inner rotor 110 has a winding, the inner rotor 110 may be energized.

(9) Seventh Embodiment Next, a hybrid vehicle to which the power transmission device 10 of the present invention is applied will be described as a seventh embodiment. FIG. 54 is an explanatory diagram showing the configuration of the drive system of the hybrid vehicle according to the seventh embodiment. As shown in the figure, the drive system of this hybrid vehicle has an engine 6
02 and EFIECU 62 for controlling its operation
0 and a power transmission device 10.

Engine 602 is a normal gasoline engine. The crankshaft 604 of the engine 602 is
The damper 606 is coupled to the inner rotor shaft 102 of the electric motor 100 provided in the power transmission device 10. The damper 606 is for preventing torsional vibration of the crankshaft 604 and the inner rotor shaft 102 due to the inertia of the electric motor 100 and the like. Outer rotor shaft 104 of motor 100 is coupled to drive shaft 610. Although not shown in FIG. 54, the drive shaft 610 is coupled to the drive wheels via a reduction gear or the like so as to transmit power.

The structure of the power transmission device 10 is the same as that described with reference to FIG. In FIG. 54, a driving circuit 20 for driving the operation of the electric motor 100, a battery 30 for exchanging electric power with the electric motor 100, and the electric motor 100
Only the ECU 12 for controlling the operation of the vehicle is shown. In the hybrid vehicle of the seventh embodiment, the ECU 1
Numeral 2 controls not only the power transmission device 10 but also the entire drive system of the hybrid vehicle. As shown in FIG. 54, ECU 12 is electrically connected to EFIECU 620. The ECU 12 indirectly controls the operation of the engine 602 by outputting a command value related to the operation of the engine 602 to the EFIECU 620. To make such control executable, the ECU 1
Various sensors and switches not shown in FIG. 54 are connected to 2. Examples of such a sensor include an accelerator pedal position sensor and a shift position sensor.

When the hybrid vehicle travels, it is necessary to output power from the drive shaft 610 at a desired rotational speed and a suitable torque. The ECU 12 calculates the required torque and the number of revolutions in accordance with the amount of depression of the accelerator detected by the accelerator pedal position sensor. Further, the magnitude of the power to be output is obtained from the product of the two. In order to travel without consuming the power of the battery 30, it is necessary to output the required power from the engine 602.
Engine 602 can be operated at various rotation speeds and torques corresponding to the power. In order to drive the hybrid vehicle efficiently, the ECU 12 selects the torque and the rotational speed with the highest driving efficiency from these various driving points. Then, the operating point is assigned to the engine
Is output to the EFIECU 620 as the operation command value. As a result, the engine 602 is controlled to operate at the set operating point.

The power output from the engine 602 operated in such a state is equal in magnitude to the required power, but the rotational speed and the torque are not always the same. Accordingly, the ECU 12 controls the operation of the power transmission device 10 to convert the power output from the engine 602 to the required rotation speed and torque and transmit the converted power to the drive shaft 610.

The method of controlling the torque conversion is as follows.
This is as already described as “(3) Operation principle of power transmission device”. The torque conversion is performed by controlling the exciting current and the torque current flowing through the coil 144 of the electric motor 100. By executing such control, the seventh
The hybrid vehicle of the embodiment can run using the engine 602 as a drive source.

"(3) Operating principle of power transmission device"
In the power transmission device 10 of the present embodiment, the battery 30
It has been explained that power can be transmitted in a form that involves the exchange of power with the power. For example, the inner rotor shaft 10
It is possible to transmit the remaining power to the outer rotor shaft 104 while regenerating part or all of the power input from Step 2 as electric power. Therefore, in the hybrid vehicle of the seventh embodiment, if the engine 602 is operated so as to output power larger than the power to be output from the drive shaft 610,
The surplus power is regenerated by the power transmission device 10 and the battery 30
It is also possible to drive while charging. Further, by controlling the current of the electric motor 100 to set the magnetic field to the state shown in FIG. 20, a state in which power is not transmitted to the outer rotor shaft 104 can be created, and the engine 602 can be operated even when the hybrid vehicle is stopped. Drive and battery 3
0 can be charged.

As described above, the power transmission device 10 according to the present embodiment receives the supply of power from the battery 30 to power the electric motor 100, and regardless of the presence or absence of power input from the inner rotor shaft 102, It is also possible to output power. Therefore, in the hybrid vehicle of the present embodiment, the vehicle can be driven by the torque output from the electric motor 100 even when the engine 602 is stopped, for example. Of course, the engine 602
Is operating at a certain operating point, the motor 10
It is also possible to perform torque assist by powering 0.

Further, the power transmission device 10 of the present embodiment can function also by using the outer rotor shaft 104 as a power input shaft. Therefore, the hybrid vehicle of the present embodiment can apply so-called regenerative braking by regenerating the rotation of the drive wheels as electric power by the electric motor 100. Also, the rotation of the drive wheels is transmitted to the inner rotor shaft 102,
It is also possible to apply a so-called engine brake.

Naturally, the power transmission device 10 of this embodiment can also run the electric motor 100 and rotate the inner rotor shaft 102 by receiving the supply of power from the battery 30. Therefore, the electric motor 100 can be used as a starter motor of the engine 602.

Although FIG. 54 shows the case where the electric motor 100 of the first embodiment is used as a hybrid vehicle, the electric motors 200, 300, and 300 described in each of the other embodiments are used.
Needless to say, 400 and 500 are applicable respectively.

Although various embodiments have been described above with respect to the electric motor, the power transmission device, and the hybrid vehicle of the present invention, the present invention can be embodied in various other forms without changing the gist thereof. For example, a hybrid vehicle is merely an example to which the electric motor and the power transmission device of the present invention are applied. The power transmission device of the present invention can function as a so-called power output device by being connected to various motors. This power output device is applicable to various devices that require power having a predetermined rotation speed and torque, such as a hybrid vehicle described above, a transport machine such as a train, and a machine tool.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view in a cross section orthogonal to a rotation axis of a motor as a first embodiment.

FIG. 2 is a cross-sectional view in a cross section along a rotation axis of the electric motor as the first embodiment.

FIG. 3 is a cross-sectional view in a cross section orthogonal to a rotation axis of an inner rotor of the electric motor as the first embodiment.

FIG. 4 is a sectional view in a section orthogonal to a rotation axis of a stator of the electric motor as the first embodiment.

FIG. 5 is a cross-sectional view in a cross section orthogonal to a rotation axis of an outer rotor of the electric motor as the first embodiment.

FIG. 6 is a sectional view in a section along a rotation axis of an inner rotor of the electric motor as the first embodiment.

FIG. 7 is a sectional view in a section along a rotation axis of a stator of the electric motor as the first embodiment.

FIG. 8 is a sectional view in a section along a rotation axis of an outer rotor of the electric motor as the first embodiment.

FIG. 9 is a perspective view of an inner rotor of the electric motor as the first embodiment.

FIG. 10 is a perspective view of a stator core of the electric motor as the first embodiment.

FIG. 11 is a perspective view of a stator of the electric motor as the first embodiment.

FIG. 12 is an explanatory diagram showing a state of connection of an outer rotor of the electric motor as the first embodiment.

FIG. 13 is an explanatory diagram showing a configuration of a power transmission device as the first embodiment.

FIG. 14 is a circuit diagram showing a drive circuit of the power transmission device.

FIG. 15 is an explanatory diagram showing a magnetic circuit in the electric motor as the first embodiment.

FIG. 16 is an explanatory diagram showing a magnetic circuit in a conventional electric motor.

FIG. 17 is an explanatory diagram illustrating a first state when the electric motor according to the first embodiment operates.

FIG. 18 is a graph showing a relationship between an output torque and a slip amount in the induction machine.

FIG. 19 is an explanatory diagram showing a change in output torque in the electric motor of the present embodiment.

FIG. 20 is an explanatory diagram illustrating a second state when the electric motor according to the first embodiment operates.

FIG. 21 is a cross-sectional view in a cross section orthogonal to a rotation axis of a motor as a second embodiment.

FIG. 22 is a cross-sectional view in a cross section along a rotation axis of the electric motor as the second embodiment.

FIG. 23 is a cross-sectional view in a cross section orthogonal to the rotation axis of the inner rotor of the electric motor as the second embodiment.

FIG. 24 is a cross-sectional view in a cross section orthogonal to the rotation axis of the stator of the electric motor as the second embodiment.

FIG. 25 is a cross-sectional view in a cross section orthogonal to the rotation axis of the outer rotor of the electric motor as the second embodiment.

FIG. 26 is a cross-sectional view in a cross section along a rotation axis of an inner rotor of the electric motor as the second embodiment.

FIG. 27 is a cross-sectional view in a cross section along a rotation axis of a stator of the electric motor as the second embodiment.

FIG. 28 is a sectional view in a section along a rotation axis of an outer rotor of the electric motor as the second embodiment.

FIG. 29 is a cross-sectional view in a cross section orthogonal to the rotation axis of the electric motor as the third embodiment.

FIG. 30 is a cross-sectional view in a cross section orthogonal to the rotation axis of the inner rotor of the electric motor as the third embodiment.

FIG. 31 is a cross-sectional view in a cross section orthogonal to the rotation axis of the stator of the electric motor as the third embodiment.

FIG. 32 is a sectional view in a section orthogonal to a rotation axis of an outer rotor of the electric motor as the third embodiment.

FIG. 33 is a sectional view in a section along a rotation axis of an inner rotor of the electric motor as the third embodiment.

FIG. 34 is a power transmission device 1 using the electric motor of the third embodiment.
It is explanatory drawing which shows the structure of 0A.

FIG. 35 is a flowchart showing a control flow relating to coupling of an inner rotor and a second inner rotor of the electric motor according to the third embodiment.

FIG. 36 is a cross-sectional view in a cross section orthogonal to the rotation axis of the electric motor as the fourth embodiment.

FIG. 37 is a cross-sectional view in a cross section along a rotation axis of a motor as a fourth embodiment.

FIG. 38 is a cross-sectional view in a cross section orthogonal to the rotation axis of the inner rotor of the electric motor as the fourth embodiment.

FIG. 39 is a cross-sectional view in a cross section orthogonal to the rotation axis of the stator of the electric motor as the fourth embodiment.

FIG. 40 is a cross-sectional view in a cross section orthogonal to the rotation axis of the outer rotor of the electric motor as the fourth embodiment.

FIG. 41 is a perspective view of an inner rotor of a motor as a fourth embodiment.

FIG. 42 is a flowchart showing a flow of control of the rotor pitch of the electric motor as the fourth embodiment.

FIG. 43 is a cross-sectional view in a cross section orthogonal to the rotation axis of the electric motor as the fifth embodiment.

FIG. 44 is a cross-sectional view of a cross section along a rotation axis of a motor according to a fifth embodiment.

FIG. 45 is a cross-sectional view in a cross section orthogonal to the rotation axis of the inner rotor of the electric motor as the fifth embodiment.

FIG. 46 is a cross-sectional view in a cross section orthogonal to the rotation axis of the stator of the electric motor as the fifth embodiment.

FIG. 47 is a cross-sectional view in a cross section orthogonal to the rotation axis of the outer rotor of the electric motor as the fifth embodiment.

FIG. 48 is a cross-sectional view in a cross section along a rotation axis of an inner rotor of an electric motor as a fifth embodiment.

FIG. 49 is a cross-sectional view in a cross section along a rotation axis of a stator of an electric motor as a fifth embodiment.

FIG. 50 is a cross-sectional view in a cross section along a rotation axis of an outer rotor of an electric motor as a fifth embodiment.

FIG. 51 is an explanatory diagram showing a state of connection of an outer rotor of an electric motor as a fifth embodiment.

FIG. 52 is an explanatory diagram showing a configuration of a power transmission device 10B as a sixth embodiment.

FIG. 53 is an explanatory diagram showing a connection between a drive circuit and a motor in a configuration of a power transmission device as a sixth embodiment;

FIG. 54 is an explanatory diagram showing a configuration of a hybrid vehicle as a seventh embodiment.

FIG. 55 is an explanatory diagram showing a configuration of a conventional hybrid vehicle.

FIG. 56 is a cross-sectional view of a conventional electric motor having two rotation shafts in a cross section orthogonal to the rotation shaft.

[Explanation of symbols]

10, 10A, 10B power transmission device 12 ECU 13 CPU 14 ROM 15 RAM 16 clock 17 input port 18 output port 20, 21 driving circuit 22, 23 current sensor 24, 25 filter 26 , 27 ADC 30 Battery 32, 33 Current sensor 34, 35 Filter 36, 37 ADC 40 Slip ring 100 Electric motor of the first embodiment 102 Inner rotor shaft 104 Outer rotor shaft 106, 107, 108 Bearing 110: inner rotor of the first embodiment 112: inner rotor core 114: permanent magnet 116: bolt 118: aluminum case 120: lid 122: bolt 140: stator 142 of the first embodiment 142: stator core 144: coil 146: bolt 147, 148 Flange 149 ... pi 150 resin mold 170 outer rotor 172 of first embodiment outer rotor core 174 coil 176 case 177 flange 178 fixing ring 200 electric motor of second embodiment 202 inner rotor shaft 204 outer rotor shaft 206, 207, 208 ... Bearing 210 ... Inner rotor 212 of the second embodiment 212 ... Inner rotor core 214 ... Permanent magnet 216 ... Bolt 240 ... Stator 242 ... Stator core 244 ... Coil 247,248 ... Flange 270 ... Outer rotor 272 of the second embodiment ... Outer rotor core 274 ... Permanent magnet 277 ... Flange 278 ... Bolt 300 ... Electric motor 302 of the third embodiment 302 ... Inner rotor shaft 303 ... Inner rotor shaft rotation speed sensor 304 ... Outer rotor shaft 305 ... Outer rotor shaft rotation speed Sensor 306 ... Clutch disk 308 ... Clutch 310 ... Inner rotor of the third embodiment 312 ... Inner rotor core 314 ... Rotor bar 316 ... Permanent magnet 318 ... Second inner rotor core 340 ... Stator 342 ... Stator core 344 ... Coil 370 ... Coil of the third embodiment Outer rotor 372: outer rotor core 374: permanent magnet 377: flange 400: electric motor of the fourth embodiment 402: inner rotor shaft 404: outer rotor shaft 406: actuators 410, 410A, 410B: inner rotor 412 of the fourth embodiment: inner Rotor core 414 Permanent magnet 440 Stator 442A, 442B of the fourth embodiment Stator core 444A, 444B Coil 446A, 446B Guide part 470 Outer rotor 47 of the second embodiment ... Outer rotor core 474 ... Rotor bar 500 ... Electric motor 502 of the fifth embodiment 502 ... Inner rotor shaft 504 ... Outer rotor shaft 506,507,508 ... Bearing 510 ... Inner rotor 512 of the fifth embodiment 512 ... Inner rotor core 514 ... Permanent magnet 540 ... Fifth embodiment Example stator 542 ... stator core 544 ... coil 547, 548 ... flange 570 ... outer rotor 572 of the fifth embodiment ... outer rotor core 574 ... coil 602 ... engine 604 ... crankshaft 606 ... damper 610 ... drive shaft 620 ... EFIECU

Claims (21)

[Claims] An electric motor having two relatively rotatable rotary shafts on the same axis, wherein a magnetic element serving as an element contributing to the formation of a magnetic circuit is concentrically formed around the rotary shaft from the inside. A first magnetic element,
A second magnetic element, a third magnetic element, and the two rotation axes are respectively coupled to any two of the first to third magnetic elements; An electric motor, wherein each magnetic element is configured to form a magnetic circuit extending from the magnetic element to the third magnetic element through the second magnetic element. 2. An electric motor comprising two relatively rotatable rotary shafts on the same axis, wherein the first rotor, the stator, and the second rotor are arranged concentrically around the rotary shaft from the inside in this order. The first rotor is coupled to one of the rotation shafts, the second rotor is coupled to the other of the rotation shafts, and the stator is configured to circumferentially form a plurality of cores. An electric motor, wherein said electric motor is formed by arranging and connecting said circumferentially adjacent cores with a non-magnetic material. 3. The electric motor according to claim 2, wherein the stator is fixed between the cores by a resin mold. 4. The electric motor according to claim 2, wherein the stator has a coil wound around a plurality of cores,
A stator that can generate a magnetic field by energizing the coil; one of the first rotor and the second rotor is a rotor having a permanent magnet; and the first rotor and the second rotor An electric motor, wherein the other rotor is a rotor having a structure capable of forming the stator and the induction machine. 5. The electric motor according to claim 4, wherein the coil is concentratedly wound around a core provided on the stator. 6. The electric motor according to claim 4, wherein said one rotor includes permanent magnets arranged radially. 7. The electric motor according to claim 4, wherein said other rotor is a rotor having a structure capable of forming said stator and a winding type induction machine. 8. The electric motor according to claim 4, wherein the other rotor is a rotor having a structure capable of forming the cage and a cage induction machine. 9. The electric motor according to claim 8, wherein the other rotor is the first rotor, and further inside the first rotor is not restrained by the first rotor by switching. An electric motor including a permanent magnet that can take either a rotatable state or a rotatable state integrally with the first rotor. 10. The electric motor according to claim 2, wherein the first rotor and the second rotor are both rotors provided with permanent magnets. 11. The electric motor according to claim 2, comprising, as the first rotor, two rotors each having a rotor having a permanent magnet arranged in series in a direction of the rotation axis. An electric motor wherein a positional relationship of a rotor can be changed in a circumferential direction of the rotating shaft. 12. The electric motor according to claim 2, wherein one of the first rotor and the second rotor includes a permanent magnet, and the stator and the one rotor form a vernier motor. An electric motor having a structure. 13. The electric motor according to claim 12, wherein the other rotor different from the one rotor has a structure capable of forming a winding type induction machine, and the winding is formed on the one rotor and the stator. An electric motor characterized by being wound so as to be able to efficiently interlink magnetic flux from the motor. 14. An input shaft and an output shaft provided coaxially, a motor coupled to both, and control means for controlling the operation of the motor, wherein power is input from the input shaft and the output A power transmission device capable of outputting power from a shaft, wherein the electric motor is concentrically formed around the input shaft and the output shaft, and is connected to the first rotor connected to the input shaft and the output shaft. A second rotor and one stator, and a magnetic circuit passing through all of the first rotor, the second rotor, and the stator is formed, and the stator passes a current. A motor that is wound with windings that can affect the strength of the magnetic circuit by controlling the current flowing through the windings of the stator; A power transmission device which is means for controlling magnetic coupling with the second rotor. 15. The power transmission device according to claim 14, wherein the control unit controls a current flowing through a winding of the stator to thereby generate a magnetic field between the first rotor and the second rotor. A power transmission device that is a means for interrupting a circuit. 16. The power transmission device according to claim 14, wherein the control means controls a current flowing through a winding of the stator to generate a positive torque between the stator and the second rotor. A power transmission device that is a means for generating. 17. The power transmission device according to claim 14, wherein the control unit regenerates a part of the power input from the input shaft as electric power via the stator, and regenerates the remaining power. A power output device that is a means for transmitting to the output shaft. 18. The power transmission device according to claim 14, further comprising detection means for detecting a difference between the number of revolutions of the input shaft and the number of revolutions of the output shaft, wherein the electric motor comprises: An outer rotor comprising: the second rotor is an inner rotor capable of forming a cage induction machine with the stator; further inside the inner rotor, the inner rotor is rotatable without being restricted by the inner rotor; An electric motor having a permanent magnet that can take any of a rotatable state integrally with the inner rotor, wherein the control means, in addition to the control, determines an absolute value of a difference between the number of rotations detected by the detection means. A power transmission device which is a means for enabling a permanent magnet provided inside the inner rotor to be rotatable integrally with the inner rotor when the value is equal to or less than 19. The power transmission device according to claim 14, wherein the electric motor includes, as an inner rotor located inside the first rotor or the second rotor, a rotor having a permanent magnet as the input shaft. And two rotors arranged in series in the direction of the output shaft, and wherein the positional relationship between the two rotors can be changed in the circumferential direction of the input shaft and the output shaft, The control device may further include, in addition to the control, a positional relationship between the two rotors such that a strength of a magnetic coupling between the inner rotor and the stator changes according to a magnitude of a torque input from the input shaft. A power transmission device that is a means for changing the power. 20. The power transmission device according to claim 14, wherein one of the first rotor and the second rotor of the electric motor is a winding-type rotor having windings wound thereon. A power transmission device including a rotor control device that controls an interaction between a magnetic field generated in a wire-wound rotor and the magnetic circuit by controlling a current flowing through a winding wound around the linear rotor. 21. A hybrid vehicle comprising a prime mover and a power transmission device according to claim 14 coupled to a drive shaft having a rotating shaft and wheels of the prime mover, the hybrid vehicle being capable of traveling by at least power output from the prime mover.