JP2851636B2 - Multiple stator induction motor - Google Patents

Description

The present invention has a single rotor and a plurality of stators,
A voltage induced in a rotor conductor portion facing one of the plurality of stators by rotating an arbitrary stator and a corresponding conductor portion of the rotor facing the other stator. Causes a phase difference between the induced voltage and
The present invention relates to an induction motor having a so-called multiple stator configuration that can arbitrarily change the rotation speed and generated torque of a rotor.

[Conventional technology]

Conventionally, when a squirrel-cage induction motor, which is generally used, is started, a means for controlling a starting current includes a star delta start, a reactor start, a start compensator start, and the like. However, although the starting current can be controlled, the starting torque cannot be improved.

Further, in the wound motor, the starting torque can be improved by changing the resistance value of the secondary resistor,
Use of a brush and a stop ring was inevitable, and maintenance was difficult.

To deal with the above problems, for example, Japanese Patent Application Laid-Open
There is a technique disclosed in -29005. This device has two sets of rotor cores installed on the same axis, and two independent stator windings opposed to the rotor core.
Pairs of stators, cage-type conductors that are commonly installed across the rotor cores and are short-circuited at both ends through short-circuit rings, respectively, and cage-type conductors between the two rotor cores. A high-resistance element that short-circuits the cage conductors at the center is provided.When starting, the phases of the stator windings are shifted by 180 °, and during operation after startup, power is supplied in phase. This is a twin-core squirrel-cage motor, which is designed to increase the starting torque by shifting the phase between the stator windings by 180 ° at start-up to improve the starting characteristics. It is characterized in that it can be operated with normal torque characteristics by matching the phases between the two. Therefore,
Although the effect of improving the startability is recognized, when increasing or decreasing the rotational speed under load, sufficient torque should be secured and a device that automatically changes the phase difference with less shock should be provided. However, the purpose is only to decrease the starting current and increase the starting torque. Also, the phase difference
Only 180 ° and 0 ° could be set and held, and did not have a wide range of loads. Therefore the starting torque is the phase difference
Since it was limited to a torque characteristic of 180 °, it could not cope with a wide range of changes in load.

Here, the applicant has disclosed in Japanese Patent Application Laid-Open No. 62-260590 that the speed control area can be set to any desired speed with a wide range of speed control and stepless speed control, and can be started with any torque. Also disclosed is an induction motor having a plurality of stators and having excellent torque characteristics and efficiency over the entire speed range from the starting point to the maximum rotation speed.

[Problem to be Solved by the Invention] The present invention is to further improve the prior art,
Japanese Patent Application Laid-Open No. 62-260590 discloses an induction motor having a plurality of stators, in which at least one of the plurality of stators is rotatably formed concentrically with a rotor shaft as means of variable speed.
By rotating at least one of the rotatably formed stators, a phase difference is generated in voltages induced in the rotor conductors facing the plurality of stators, respectively. As a result, a voltage is applied to the resistance material between the rotor cores, a current flows between the plurality of conductors via the resistance material, and a large torque can be secured even in a low-speed rotation region. The rotation of the rotating stator that causes a phase difference in the voltage induced in the slave conductor is performed by providing an engaging member such as a gear on the outer periphery of the rotating stator rotatably provided on the inner periphery of the motor frame. However, in order to secure the rotating position of the rotating stator in accordance with the rotation speed of the rotor and the fluctuation of the external load, the rotation of the rotating stator was performed. A rotating position sensor, a rotor tachometer, a rotating stator driving device, and the like, and a control device controlled by various sensors are required.

When such an induction motor having a plurality of stators is used in a device only for the purpose of improving startability, speed and torque control in the medium speed range is unnecessary and is expensive if used as it is. Become. However, there are many devices that require a smooth change in rotation from start to rated rotation, and in order to solve these problems, due to the characteristics of general induction motors, there is a margin for starting torque. You have to use a big motor.
Further, there is a problem that even a motor that generates a high torque at the time of startup disclosed in Japanese Patent Application Laid-Open No. 54-29005 and whose shock increases due to a gradual increase in rotation is avoided. In order to solve the above-mentioned problems, the present invention relates to the development of a multiple stator induction motor that can provide a low-price multi-stator induction motor that can smoothly increase the rotation from the start of a device having a large starting load to the rated rotation. Subject.

[Means for solving the problem]

In order to achieve the above object, the present invention relates to a method in which a plurality of conductors provided on a plurality of rotor cores provided at arbitrary intervals on the same rotating shaft are connected to each other in a communicating manner and integrally formed. And a plurality of conductors are short-circuited and connected by a resistance material between the plurality of rotor cores, and the outer periphery of the outer periphery is concentric with the plurality of rotor cores in a machine frame. A plurality of stators are provided side by side in a portion, and at least one of the plurality of stators is rotated concentrically with the rotor and with a reluctance torque of the rotor. Formed on the stator, the rotating stator, between the voltage induced in the rotor conductor portion facing one stator, and the voltage induced in the rotor conductor portion facing the other stator Is formed in a voltage phase shifter for generating a phase difference, An electric device for providing a driving force action or a braking force action with respect to the rotation of the rotating stator from the starting position to the steady operation position is provided, and the rotating stator is formed so as to fix the rotating stator when the motor stops. The rotating stator has a starting position and a steady operating position for each of the left and right rotations of the rotor, and the starting position is provided at an intermediate portion of a rotating range of the rotating stator. Further, a means for solving the above-mentioned problem is provided by providing a start position detector and a steady operation position detector of the rotating stator inside and outside the machine frame.

(Operation)

In the multiple stator induction motor, at least one of the plurality of stators is formed as a rotating stator that rotates with a reluctance torque of the rotor, and the rotating stator moves from a starting position to a steady operation position. An electric device that provides a driving force action and a braking force action to the rotation is provided, and the rotating stator is turned from a starting position to a steady operation position by a reaction torque received from the rotation of the rotor, and braking of the electric device is performed. The action prevents sudden rotation of the rotating stator due to the repulsive torque. Also, when the reaction torque at the time of starting is weak due to a load, the electric device acts as a driving device and rotates the rotating stator to the steady operation position.

Further, the electric device has an operation of fixing the rotating stator by stopping the electric device, and can fix the rotating stator at the start position or the steady operation position.

Further, since the starting position is provided in the middle portion of the rotating range of the rotating stator, the rotating stator can be formed to be capable of coping with the forward and reverse rotation of the rotor. Thus, the rotating stator also rotates forward and backward.

Since the start position and the normal operation position are provided with position detectors for detecting the respective positions, when the stator is at the start position or the steady operation position, the position detectors respectively detect the positions, and The device can reliably stop and fix the rotating stator at the start position or the steady operation position by the fixing operation of the stator of the electric device according to the signal of the position detector.

With the above-described operation, it has become possible to provide the simplest and cheapest multiple stator induction motor with improved startability, in which the transition from low-speed rotation to rated rotation can be smoothly performed from start to steady operation.

The power supply to the multiple stator induction motor of the present invention can be implemented in a single phase or a three phase.

〔Example〕

An embodiment of the present invention will be described with reference to FIGS. Reference numeral 1 in FIG. 1 is a multiple stator induction motor according to the present invention, and the induction motor has the following configuration.

Rotor portions 2 and 3 made of an iron core are mounted on a rotor shaft 4 at an arbitrary interval, and the rotor portion is formed by casting aluminum or the like into a rotor core to form a plurality of conductors 5 and a plurality of conductors 5. Short-circuit rings 6 and 7 are formed at one end and an end 51 is formed at the other end. Further, the rotor 8 is integrally formed between the rotor portions 2 and 3 by connecting a conductor 55 to the end portion 51 of the conductor 5 in a communicating manner. Further, the conductor 55 connected in a communicating manner between the rotor parts 2 and 3 is short-circuited and connected via a resistance material r, for example, aluminum, a copper-nickel alloy, a nickel-chromium alloy, an iron-chromium alloy, and stainless steel. The rotor part
The portions other than the conductor 55 and the resistance material r between the two are formed by a space or a non-magnetic material.

The rotor portions 2 and 3 are provided with a plurality of ventilation drums 12 communicating with both side portions 10 and 11 of the rotor 8. Further, the stators 25, 31 are provided with a plurality of ventilation ducts 60 communicating with both sides of the stator. Further, the plurality of resistance members r can be formed in the cooling body 13 as, for example, a zigzag shape or any other cooling stirrer.

Bearing plates 15 and 16 provided on both sides of a cylindrical machine frame 14 are integrally assembled on both sides by bolts 17, and cooling impellers 19 and 20 are mounted on both sides of the rotor 8. Both ends of the shaft 4 are supported by bearings 21, 21 fitted to bearing plates 15, 16, and the rotor 8 is rotatable.

As shown in FIGS. 1 and 2, a rotating stator 31 having windings 22 and 23 applied concentrically to rotor cores 2 and 3 and a second stator 25 face each other. Set up. A sliding bearing 26 is provided between the machine frame 14 and the rotating stator 31 so that the sliding bearing 26
Is fixed by a stop ring 28 fitted to the machine frame 14. The second stator 25 is a fixed stator fixed to the inner wall surface of the machine casing 14. The rotating stator 31 which is rotatable and which is rotatable relative to the second stator 25 fixed to the machine frame 14 is formed in a voltage phase shifter.

The cooling device 73 is fixed to the machine frame 14, and the suction unit 74A of the cooling device 73 is connected to the inside of the machine frame 14.

A plurality of openings 39 are opened in the machine frame 14 between the rotor cores, and the plurality of openings 39 are provided with an arbitrary number of blowing ports 65 and exhaust ports 66.
The exhaust port 66 communicates with the suction port 74A. Further, a plurality of ventilation holes 40 are formed in the bearing plates 15 and 16.

Although the example of the slide bearing is shown for the rotation of the rotating stator 31, a roller bearing or a ball bearing is provided in addition to the present example, or the outer periphery of the rotating stator is supported from one side of the rotating stator. There is a method of rotating the support around a rotor shaft, and the method is not limited to this embodiment. (FIG. 5) Next, FIG. 3 is a side sectional view between rotor portions including the resistance material r and the conductor 55. A conductor 55 having a curved portion is fixed to the end portions 51 of the rotor portions 2 and 3 around the support body 75. The rotor parts 2 and 3 to which the conductors 55 are fixed are mounted on the rotating shaft 4. Here, the fixation includes the brazing. Further, the resistance material r is connected and welded between the adjacent conductors. At this time, the resistor r is integrally formed so as to surround the conductor 55 by welding (FIG. 4), or a plurality of resistance pieces are welded between the conductors. At this time, the resistance material r is formed concentrically with the rotating shaft 4 in contact with the support 75. A support facing the resistance material r
Insulation material is applied to the circumference of 75 or the entire circumference.

The support 75 is mounted on a ring 76 fitted on the rotating shaft 4,
By caulking the side end of the ring 76 together with the stopper 77, the support 75 is formed integrally with the ring 76, and the ring 76 is
Fit between upper rotor parts. At this time, the ring 76 may be coated for insulation.

The conductor 55 is formed by the conductor 56 and the conductor 57. The conductor 56 having a curved portion and the conductor 57 are provided symmetrically and the joined portion is fixed by welding means such as spot welding. At this time, it is easier to process and weld the conductors 56 and 57 in a plate shape. Further, the conductor 56 and the conductor 57 may be formed integrally by providing a curved portion with one member.

Next, a method and an apparatus for rotating a rotating stator according to an embodiment of the present invention will be described with reference to FIG. Rotating stator
A worm wheel 33 is fitted on the outer peripheral surface of one side of 31 and a small forward / reverse rotation motor fixed to the outer peripheral portion of the machine frame 14
A worm gear 36 is mounted on 35. Machine frame 14 from opening 37
A worm gear 36 partially inserted therein and a worm wheel 33 fitted to the rotating stator 31 are engaged with each other, and the worm gear is rotated via an electric device 30 including a small motor 35 and the worm wheel 33 and the worm gear 36. The rotating stator 31, which is connected to the moving stator 31 and is rotatable in relation to the second stator 25 fixed to the machine frame 14, is formed in the voltage phase shifter as described above.

Worm gear 36 and worm wheel formed here
The rotation shaft 33 of the small motor 35 of the worm gear 36 and the rotation shaft 4 of the rotor 8 of the worm wheel 33 are at right angles to each other, and have a small torsion angle of the gear so that they cannot be reversed. It is also possible to form the rotating shaft 4 and the rotating shaft of the small motor 35 at an arbitrary intermediate position parallel to each other or parallel to a right angle.

On the other hand, the rotating stator 31 and the machine casing 14 are configured as follows.

As described above, the worm wheel 33 is fixed to the outer periphery of the rotating stator 31 with an extension required for left-right rotation. Protrusions 46 and 47 indicating a steady operation position are fixed to both ends in the extending direction of the worm wheel 33, and also serve as stoppers for preventing unnecessary rotation.

On the machine frame side, limit switches 41, 4 serving as a steady operation position detector for detecting a steady operation position of the rotating stator 31 are provided.
3, and stoppers 42 and 44 for preventing unnecessary rotation together with the projections 46 and 47 are provided.

Further, a concave portion 48 is provided on the outer periphery of the rotating stator 31, and a limit switch 45 is provided as a starting position detector for detecting a starting position by contacting the concave portion 48 from the machine frame 14 side.

By the way, when the extension intermediate portion of the worm wheel 33 contacts the worm gear 36, that is, when the limit switch 45 and the concave portion 48 contact, the rotating stator 31 is configured to be in the starting position.

In the above configuration, the limit switches 41, 43, 45 as the start position detector and the steady operation position detector, and the worm wheel 33 and the worm gear 36 as the electric device are not limited to the members of the present embodiment, As a device for determining the start position and the steady operation position, an electric solenoid, a gas compressor or the like is used, and as a small motor of the electric device, a pulse motor or the like can be used.

By the way, in the case of the multiple stator induction motor of the present embodiment configured to generate a phase difference by the rotation of the rotary stator 31, when the limit switch 45 is in contact with the concave portion 48 of the rotary stator 31. 180 ° phase difference in electrical angle, protrusion 46 or 4
7 is configured such that when the limit switch 41 or 43 is hit, the phase difference becomes 0 ° in electrical angle. However, depending on the load condition, the set value of the phase difference is 90 ° or 0 ° <θ <
Any of 180 ゜. In the present embodiment, the setting of the phase difference is 0 ° to 180 °.

Next, the rotating stator 31 in the first to third embodiments is described.
An example of the connection of the windings 22 and 23 wound around the second stator 25 will be described with reference to FIGS. 6 and 7. FIG. Further, here, a case where a three-phase power supply is used is described, and a single-phase power supply is omitted.

First, FIG. 6 shows a rotating stator 31 and a second stator.
The windings 22 and 23 applied to each of the 25 are star-connected and connected in series to a power supply. That is, the terminals A, B, and C of the winding 22 of the rotating stator 31 are connected to the commercial three-phase power supplies A, B, and C, and the terminals a, b, and c of the winding 22 are connected to the second stator 25. Terminal of winding 23
A, B and C are connected, and terminals a, b and c of the winding 23 are short-circuited and connected.

FIG. 7 shows a rotating stator and a second stator 3.
1,25 windings 22 and 23 are connected in series and delta-connected to a commercial three-phase power supply, but detailed description thereof will be omitted.

 Hereinafter, the operation of the above configuration will be described.

When current is supplied to the winding 22 of the rotating stator 31 from a commercial three-phase power source, a rotating magnetic field is generated in the stators 31 and 25 to induce a voltage in the rotor 8, and a current flows through the conductor 5 of the rotor 8 to rotate the rotor 8. The child 8 rotates. When the amount of rotation of the rotating stator 31 with respect to the second stator 25 is set to zero, the voltages induced in the conductor 5 of the rotor 8 by the respective stators 31 and 25 have no phase shift. As will be described in detail later, no current flows through the resistance material r, and in this state, the motor has the same torque characteristics as a general induction motor.

Next, a case where the rotation stator 31 is rotated by θ at the phase angle will be described. The phases of the magnetic fluxes φ ₁ and φ ₂ of the rotating magnetic field generated by the rotating stator 31 and the second stator 25 are determined by the arbitrary conductors 5 of the rotor 8.
Are shifted by θ, so that the stator 31 and the second
The voltage induced on the conductor 5 of the rotor 8 by the stator 25,
2 will be shifted by θ. Now the second stator
With reference to the voltage 2 induced in the conductors 5 of the rotor 8 by 25, the voltage 2 = SE. Where S is the slip, E
Is the induced voltage at the time of slip 1. At this time, the voltage 1 induced on the conductor 5 by the rotating stator 31 is 1 = SE
ε ^jθ .

FIG. 8 shows the slip S of the rotor 8 when the resistance material r for short-circuiting the plurality of conductors 5 is not mounted,
It shows the relationship between the rotor input and the active power P. When the voltage phase is θ = 0 °, the active power P becomes maximum, and when 0 ° <θ <180 °, it becomes smaller. . Here, if the resistance and inductance of the conductor 5 are R and L, and the angular frequency of the power supply is ω, the maximum value of the active power P appears when S = (R / ωL).

Since the active power P is proportional to the drive torque of the induction motor, the voltage induced on the rotor 8 can be adjusted by rotating the rotating stator 31 to control the speed of the rotor, but the phase difference is reduced. The torque suddenly decreases as the size increases, and is not practical.

Next, the resistance from the short-circuit ring 7 of the conductor 5 of the rotor 8 to the resistance material r is R ₁ , R ₂ , and the inductance is L ₁ , L ₂
And then, the angular frequency of the power source was omega, if the resistance r of the resistor material r for short-circuiting each of the conductors 5, the electrical equivalent circuit of the rotor 8 becomes as shown in FIG. 9, reference numeral I _1, I ₂ and I ₃ indicate the current flowing through each branch.

Next, when the circuit shown in FIG. 9 is converted into an equivalent circuit viewed from both stators 31 and 25, the circuit becomes as shown in FIG. 10, where R ₁ = R ₂ , L ₁
= L ₂ and θ = 0 °, I ₃ = I ₁ −I ₂ = 0, and no current flows through the resistor r. This means that when θ = 0 °, the torque T is equal to the value when there is no r. Therefore, when θ = 0 °, it has the same torque characteristics as the conventional induction motor.

Next, when R ₁ = R ₂ , L ₁ = L ₂ and θ = 180 °, I ₁ =
I ₂ , I ₃ = I ₁ −I ₂ = 2I ₁ , and if the resistance of the rotor conductor 5 is R ₁ + R ₂ = R in the conventional induction motor, the result is the same as that when R is increased to R + 2r. I have.

Next, the operation of connecting the windings 22, 23 wound around the rotating stator 31 and the second stator 25 in series will be described with reference to FIG.

Since the windings 22 and 23 are connected in series, a current is input from the commercial three-phase power supply to the winding 22 and a current flows between the windings 22 and 23. Regardless of the difference or the difference in the capacity of the two stators 31, 25, regardless of the difference, the magnitude of the current flowing through the respective windings 22, 23 is equal, and therefore, the rotation stator 31 and the second The effect that the magnitude of the current induced from each of the stators 25 and flowing into the conductors 5 of the rotor 8 becomes equal, and the rotation difference between the rotating stator 31 and the second stator 25, that is, the magnetic flux of the rotating magnetic field. In accordance with the generated phase shift, an action is generated in which the magnitude of the current flowing from each of the stators 31 and 25 to the conductor 5 of the rotor 8 becomes equal, and the voltage between the stators 31 and 25 is reduced. The current of the vector difference caused by the phase difference necessarily flows through each of the plurality of conductors 5 through the resistor. Due to the synergistic effect of the generated action, the efficiency can be improved and a large torque can be output in each shift range as shown in FIG. 11, as in the slip and torque characteristics. This makes it easy to start each time, and it can be used arbitrarily, such as smooth start according to the start characteristics of the load, or starting at high output, and it can be used as a power source that repeatedly starts and stops frequently. Can respond optimally. As described above, the speed change of the rotor 8 is performed by the rotation stator.
By controlling the phase shift by rotating the rotor 31, the rotor 8
The rotation speed of the rotor 8 can be arbitrarily changed only by controlling the current flowing through the conductors 5 to increase or decrease.

It should be noted that the magnitude of the current flowing from each of the rotating stator 31 and the second stator 25 in which the windings 22 and 23 are connected in series to the conductors 5 of the rotor 8 is different between the plurality of conductors 5. Resistance material r ...
Are independent of the resistance value r and the slip of the resistance members r... P (P = the number of pole pairs, θ
= Phase angle), where the ratio is Pθ
= Π is maximum and Pθ = 0 and becomes zero.) If Pθ is constant, the slip and torque characteristics are the same as those when the secondary insertion resistance of a general wound-type induction motor is fixed, and Pθ becomes small. Then, the ratio of the current flowing through the conductors 5 of the rotor 8 becomes small, and reducing Pθ has the same effect as reducing the secondary insertion resistance of a general wound induction motor. When the rated currents of both stators 31 and 25 are passed, depending on the selection of the slip value and the design of the resistance value of the connecting member resistance material r even if the phase difference θ is arbitrarily changed, the rated current having the highest speed and The rated torque characteristics can be applied almost simultaneously in each shift range. Even if the windings 22 and 23 of the rotating stator and the second stators 31 and 25 are connected in series, if there is no short circuit by providing the resistance material r between the conductors 5, the fixed A voltage is hardly induced from the stator to the rotor conductors 5.
The efficiency and torque are lower than those in which the windings 22 and 23 of No. 5 are connected to the power supply in parallel.

On the other hand, when the rotating stator 31 and the windings 22 and 23 of the second stator 25 in FIG. 12 are connected in parallel to a commercial three-phase power source, the rotating stator 31 and the second stator The voltages input to the windings 22 and 23 of the stator 25 are equal, the voltages induced on the conductors 5 of the rotor 8 from each of the stators 31 and 25 are the same, and the phases of the voltages differ by Pθ. Resistor r between conductors 5 ...
The current flowing through... Is substantially proportional to (1/2) × (difference voltage induced in the rotor conductor from each of the first and second stators) ÷ (the resistance value of the resistance materials r...) Become. However, in addition to the current flowing through the resistance members r, the conductors 5 of the rotor 8 have a sum of (the sum voltage induced in the rotor conductors of the rotating stator and the second stator) ÷ (impedance of the rotor conductor). An almost proportional current is superimposed and flows. (The sum voltage is Pθ =
When π is zero and Pθ = 0, the impedance of the rotor conductor depends on the slip because it consists of the resistance of the conductor and the secondary leakage reactance, respectively.
The ratio of the current flowing between the plurality of conductors 5 through the resistance material r to the magnitude of the current flowing through the conductors 5 of the rotor 8 varies depending on the slip and resistance even if Pθ is constant. The slip and torque characteristics in the case where the constant value is constant are obtained by mixing the characteristics when the secondary insertion resistance of the general winding type induction motor is constant and the characteristics when the primary voltage of the general induction motor is controlled. The characteristics are shown in FIG. This characteristic is different from the characteristic when the windings 22 and 23 of the rotating stator and the second stators 31 and 25 are connected in series, in the case of a specific load characteristic, the range of the speed control becomes narrower. However, in the case of a load having a reduced torque characteristic, the load can be used in a wide range almost equivalent to the case of the series connection.

Next, the operation of the embodiment will be described. When the multiple stator induction motor is started by connecting to an arbitrary load, the phase shift angle of the rotating stator is set to 180 °.
_The electric device 30 is started while being started along the _s curve. When the rotor 8 is activated and starts rotating rightward, a corresponding reaction torque acts on the stator 31 side. Since a bearing is provided on the circumference of the rotating stator 31, a force of the left rotation opposite to the rotation of the rotor 8 is generated by the action of the reaction torque.
Start acting on 31. However, if the reaction torque acts on the rotating stator 31 as it is, the rotating stator suddenly has a phase difference of 0 ° and shifts to the torque curve of the Tr curve in FIG. 11 or FIG. or if the rotational speed at that time exceeds P _1, it will generate a shock due to the sudden torque change. Therefore, in this embodiment, the electric device 30 is provided.

Here, although the rotation direction of the worm gear 36 is the same as the rotation direction of the stator due to the resistance torque of the rotor, the small motor 35 with the worm gear 36 The rotation direction of 35 is set, and when the rotation of the rotor is reverse rotation, the rotation stator also rotates in reverse, so the rotation direction of the small motor 35 with the worm gear 36 mounted on it is also set to reverse rotation. I do.

The electric device 30 including the worm gear 36 controls the speed of the rapid rotation of the rotation stator due to the reaction torque of the rotor by engagement with the worm wheel 33 by the constant rotation of the worm gear 36.

That electric device 30 while gradually absorb the action of the torque at the rated rotation by the rotation of the worm gear 36 of the electric device 30 from the torque curve T _s during startup, by using the power of defiance torque,
By changing the phase difference from 180 ° to 0 °, it is intended to smoothly reach the rated rotation and maintain an efficient use state. In the present embodiment, the main phase difference is 0 ° and 180 °, but the phase difference between 0 <θ <180 ° is for transition from the quiet start to the maximum rotation smoothly with a constant torque. The electric device 30 works effectively.

When the rotation stator 31 rotates, the protrusion 47 strikes the limit switch 43, detects the steady operation position, and
Stops and the rotation is fixed at the steady operation position.

Conversely, when the power is turned off, the reaction torque to the rotating stator 31 disappears, and the rotating stator 31 is again driven by the electric device 30.
Slowly returns to the starting position with a phase difference of 180 ° by reverse rotation of. That is, when the limit switch 45 comes into contact with the concave portion 48 due to the rotation, the starting position is detected, the worm gear 36 of the electric device 30 stops, and the rotation stator 31 is fixed.

Next, when the rotor 8 starts reverse rotation, that is, left rotation, the operation is reverse to that described above.

The rotating stator 31 receives a resistance torque to the right rotation and
Also rotates in the same direction as the rotation direction of the rotation stator 31. The rotating stator 31 receives the action of the reaction torque,
The rotation stator 31 is gradually rotated to the steady operation position, and the projection 46 hits the limit switch 45, so that the rotation stator 31 is fixed to the steady operation position when the electric device 30 stops.

By the way, in the above examples, the case where the reaction torque of the rotor is sufficient torque to rotate the rotating stator 31 has been described. When the reaction torque at the time of starting is small due to the load, it takes time for the rotating stator 31 to rotate from the starting position to the steady operation position, and the rotation speed of the rotor 8 increases slowly. However, as described above, since the electric device 30 starts rotating upon activation, the electric device becomes a driving device, and the rotating stator 31 rotates to the steady operation position without stopping at the starting position.

Here, an overall block diagram for controlling the operation of the plural stator induction motor of the present invention will be briefly described.

Small motor 35 and limit switch 4 provided on motor 1
1, 43 and 45 are connected to the control unit 80. Further, a forward / reverse switching device 81 for switching between forward and reverse rotation is provided in the middle of the power supply 82 of the motor, and the forward / reverse switching device 81 is forward / reverse controlled by the control unit 80. The control unit 80 includes a switch for switching the direction of rotation of the small motor 35 for forward rotation and reverse rotation and a limit switch for use.
A changeover switch 83 is provided for switching between 41 and 43, receiving signals from the limit switches 45 and 41 or 43, and switching between normal rotation and reverse rotation.

By switching the changeover switch 83, forward / reverse switching of the motor, selection of a limit switch and switching of the rotation direction of the small motor are performed, and the motor is operated as described above.

The sequence or microcomputer control of the control unit 80 can be easily implemented by those skilled in the art.

As described above, in the electric device of the present invention, when the reaction torque due to the rotation of the rotor is relatively large, the braking device that controls the rotation speed of the rotating stator has a relatively small resistance torque due to the rotation of the rotor. At times, it becomes a driving device for the rotating stator, and in the starting position or the steady operation position, it becomes a fixing device for the rotating stator.

In addition, since the intermediate portion on the extension of the worm wheel in which the rotation angle of the rotation stator is set is formed so as to be the starting position of the rotation stator, an electric motor that can rotate forward and reverse around the starting position as it is. can do.

Further, the provision of the position detector for detecting the start position of the rotating stator and the steady operation position in each of the left rotation and the right rotation makes it possible to stop and fix the start position and the normal operation position. The starting position detector and the steady-state operating position detector, with the middle part between the electric device and the worm wheel as the starting position, enable smooth operation at high torque from low speed to high speed regardless of load fluctuations. It became.

Here FIG. 11, Fig. 12 torque curve during startup phase difference and adding explained by T _s and the torque curve Tr during operation retardation
Intersection P ₁ and is determined to be the resistance of the rotor conductor 5 and 55 to be greater than the load torque curve T ₁ leading to rated operation from the starting of the load and the resistance of the resistor material r. The generated torque of the motor 1 at the time of start-up of the load is made as of the torque curve T _s.
Next, when the rotation speed gradually increases, the phase difference gradually shifts from the starting phase difference to the operating phase difference, and the torque of the torque curve _Tr is generated.

By the way, the torque curve of a general low-resistance induction motor is Tr
When a general low-resistance type induction motor having the same Tr torque curve is used for a load having a load torque similar to the load according to the present invention, the load torque is T ₂ or less when P ₂ or less.
Obviously, it can only be used for the following loads:

The torque characteristic of the high-resistance induction motor is such that the starting torque is improved when the peak value of the torque is near S (slip) = 1, but the efficiency is reduced and the generated torque decreases as the rotation speed increases. , And the drivable load torque is greatly reduced as compared with the starting torque, which is the same result as that of a general low-resistance induction motor.

〔The invention's effect〕

According to the present invention, a complicated configuration is required when a plurality of stator induction motors capable of generating a high torque by setting the starting current within the rated current range even in a low-speed rotation range are used for a device for improving starting characteristics. Therefore, it can be formed at a low cost, and can be used for a higher load as compared with a normal induction motor.

Further, the present invention has a great effect that a plurality of stator induction motors capable of quiet start-up and smooth transition to rated rotation with constant torque can be provided at a low cost with a simple configuration.

From the above, the phase shift of the rotating magnetic field is provided between the two stators to diversify the induction, which is the torque, and to expand the applications of the induction motor that improves the startability, This can greatly contribute to any field that requires an induction motor having a high torque at a rated current or less.

[Brief description of the drawings]

1 is a multiple stator induction motor according to the present invention, FIG. 2 is a front sectional view of FIG. 1 in the embodiment, FIG. 3 is a detailed view of a resistance material portion of the multiple stator induction motor according to the present invention, FIG. 4 is a front sectional view of the resistance member portion of FIG. 1, FIG. 5 is a side sectional view of another embodiment of the rotary stator with a part omitted, and FIG.
FIG. 7, FIG. 7 is a connection diagram of windings wound on both stators, FIG. 8 is a diagram showing the relationship between rotor slip and active power, FIG. 9 is an electrical equivalent circuit diagram of the rotor, FIG. Fig. 10 is an electrical equivalent circuit diagram viewed from the stator side, Fig. 11 shows the relationship between speed and torque when the stator windings are connected in series, and Fig. 12 shows the stator windings connected in parallel to the power supply. FIG. 13 is a diagram showing a relationship between speed and torque when connected, and FIG. 13 is a simplified diagram showing control of the present invention. 1 ... variable speed induction motor, 2,3 ... rotor part, 4 ...
Rotor shaft, 5 ... Rotor conductor, 6, 7 ... Short-circuit ring, 8 ...
Rotor, 10, 11 ... both sides, 12 ... passageway body, 13 ... cooling body, 14 ... machine frame, 15, 16 ... bearing plate, 17 ... bolt, 19, 20 ... for cooling Impeller, 21 ... bearing, 22, 23 ... winding, 25 ... second stator, 26 ... sliding bearing, 28 ... stop ring, 30 ... electric device, 31 ... rotating stator, 33…
… Warm wheel, 35 …… Small motor, 36 …… Worm gear, 37 …… Opening, 40 …… Ventilation opening, 41 …… Limit switch, 42 …… Stopper, 43 …… Limit switch, 44 …… Stopper, 45 …… Limit switch, 46…
... Projection, 47 ... Projection, 48 ... Recess, 51 ... End, 55 ...
Conductor having a curved portion, 56 ... conductor, 57 ... conductor, 58 ...
Bending part, 59 ... cutout, 60 ... ventilator, 65 ... vent, 66 ... exhaust vent, 70 ... fan case, 71 ... centrifugal fan, 72 ... motor, 73 ... cooling device, 74A ... suction port, 74B ... exhaust port, 75 ... support, 76 ... ring, 77
…… Stopper, 80 …… Control unit, 81 …… Forward / reverse switching, 82
... power supply, 83 ... changeover switch, r ... resistance material.

Claims (4)

(57) [Claims] 1. A plurality of conductors mounted on a plurality of rotor cores mounted on the same rotation shaft at arbitrary intervals and connected to each other in a communicating manner to form an integral rotor. The plurality of conductors are short-circuited and connected to each other by a resistance material between the plurality of rotor cores, and a plurality of conductors are fixed to an outer peripheral portion of the machine frame and concentrically with the plurality of rotor cores. The stators are arranged side by side, and at least one of the plurality of stators is formed as a rotating stator that rotates concentrically with the rotor and with the reluctance torque of the rotor. ,
A voltage shift which causes a phase difference between the voltage induced in the rotor conductor portion facing the one stator and the voltage induced in the rotor conductor portion facing the other stator. In the multiple stator induction motor formed in the phase device, a driving force action is exerted on the rotation of the rotating stator from the starting position with a large phase difference to the steady operation position with a small phase difference due to the reaction torque of the rotor. Alternatively, a plurality of stator induction motors, provided with an electric device for giving a braking force effect. 2. The multiple stator induction motor according to claim 1, wherein the rotating stator is fixed when the electric device is stopped. 3. The rotation of the rotating stator has a starting position with a large phase difference and a steady operation position with a small phase difference for each of the left and right rotations of the rotor, and the rotating range of the rotating stator. 3. The multiple stator induction motor according to claim 1, wherein the starting position having the large phase difference is provided at an intermediate portion of the motor. 4. The apparatus according to claim 1, wherein a starting position detector having a large phase difference of the rotating stator and a steady operation position detector having a small phase difference are provided inside and outside the machine frame. A multiple stator induction motor according to any of the preceding claims.