JPS62272852A - Motor - Google Patents

Abstract

PURPOSE:To obtain rotational power of two sets or more with a device of small size and light weight, by a method wherein two rotors or more are constituted independently within the same shaft. CONSTITUTION:A center shaft is projected at side of upper and lower surfaces, and one flat motor is arranged to each of both portions. As the motor therefor, a brushless motor to rotate and drive each of rotor magnets 18, 18' by control power supply to each of stator coils 21, 21' is used. Respective motors have rotary bodies 4, 4', rotor magnets 18, 18', stator coils 21, 21', rotary yokes 22, 22', wiring circuit boards 25, 25', sensors 40, 40', and signal of the sensors 40, 40', FG signal and the like are inputted to an electronic circuit connected at outside and control power supply is performed to each of the stator coils 21, 21', whereby rotational drive power is generated independently to each of the rotor magnets 18, 18'.

Description

Detailed Description of the Invention 5. Detailed Description of the Invention [Field of Industrial Application] The present invention relates to a small motor structure, and particularly to a structure that is small, lightweight, and compact, and can realize multiple functions and high performance.

[Conventional technology]

An example of the structure of a motor that obtains rotational power from multiple locations on the same shaft is the structure described in Japanese Patent Publication No. 57-40574.

This structure has a first rotary output shaft to which a first rotor is fixed and a second rotary output shaft to which a second rotor is fixed on the same axis, and the first rotor is attached to this. The second rotor is electromagnetically coupled to a part of the first rotor, and the second rotor is electromagnetically coupled to a part of the first rotor.
It is configured to rotate following the rotor of. Therefore, this structure is configured to obtain both the first rotating shaft output and the second rotating shaft output from the rotational force of the first motor rotor, and it is not possible to obtain each output separately and control the rotation. It's also difficult. In addition, since two combined bodies each consisting of one rotor and one rotating shaft are provided as a unit structure as a five-rotation unit, it is difficult to improve assembly precision such as concentricity between each rotating combined body. Further, it is thought that the loss in the electromagnetic coupling portion is particularly large, and the power consumption of the motor for generating the first rotor power increases. Furthermore, the speed controllability of the second rotor is poor and constant speed control is difficult. The motor scale also tends to be large, and there is a limit to miniaturization.

[Problem that the invention seeks to solve]

The above conventional technology is configured to obtain a first rotational output from the rotational force of one motor and a second rotational output using a coupling, so it cannot be applied to load drive devices with significantly different rotational speeds. and high controllability of rotation.

High-precision assemblability, compactness and weight reduction, high efficiency, etc. are not considered, and it is impossible to achieve significant improvements in these aspects with this structure.

SUMMARY OF THE INVENTION An object of the present invention is to improve the drawbacks of the prior art described above and to provide a small, highly efficient, and highly controllable multifunctional motor.

[Means for solving problems]

In order to achieve the above object, in the motor of the present invention, a plurality of motors are arranged concentrically in the length direction with respect to the central axis, and at least one of the motors is rotated with a stator coil in between. The motor has a structure having a paired rotor consisting of a child magnet and a rotating yoke, or a first rotor magnet and a second rotor magnet, and prevents the occurrence of iron loss in the motor stator and the occurrence of cogging torque. By eliminating the magnetic attraction force on the bearing, etc., we aim to improve motor efficiency, reduce uneven rotation, and improve servo controllability.In addition, the concentric arrangement structure of multiple motors on a fixed shaft allows for a small and compact structure, high efficiency, Realizes high controllability, etc.

[Effect]

(1) In a structure in which a plurality of motors are arranged concentrically on a central axis, outputs from individual shafts can be easily obtained independently from the same axis, and individual control is also easy. The entire structure, including the driven load, can be significantly downsized. In addition, since the structure shares a common shaft, the number of parts can be reduced, and it is easy to assemble, so costs can be reduced.

(2) In the structure in which the air-core stator coil is used as a scissor-paired rotor, no iron loss is generated in the stator even when the rotor magnet rotates, and no cogging torque is generated.

Furthermore, since the attractive force of the rotor magnet acts only within the rotor and does not act on the stator side, the load applied to the bearing of the rotor support is also significantly reduced.

〔Example〕

The present invention will be explained below based on examples.

FIG. 1 is a diagram showing a first embodiment of the motor of the present invention.

The central shaft 1 is fixed to a boss portion of a fixed base 3 by press fitting or the like. This embodiment has a structure in which the central axis protrudes from the upper and lower surfaces of the fixed pace 3 and flat motors are arranged one at a time in each image area. A brushless motor is used to rotate the magnet (18.18'). In the first motor arranged on the upper surface side of the fixed base 3, a rotor magnet (first rotor magnet) 18 is fixed to the first rotating structure 4 via a rotating yoke 19 made of a magnetic material. The stator coil (first stator coil) 21 is fixed to the upper surface of the fixed base 3 by screws 12 at its outer peripheral edge. The rotating structure 4 passes through the center hole of the first stator coil 21, and a first rotating yoke 22 is fixed to the lower surface thereof.

A thin magnet 51 for an FG (frequency generator) having a predetermined number of poles in the circumferential direction is fixed to the lower surface of the rotating yoke 22. Furthermore, on the fixed pace surface on the bottom surface is the FG
An FG substrate 26 having a patterned conductor for signal generation on its surface is provided. A tisf 7 as a load rotating body is fixed to the upper part of the rotating structure 4, and the rotating structure 4 is rotatably engaged with the central fixed shaft 1 through bearings 5α and 5A at its center. 6 is a preload piece that applies preload to the bearings 5α and 5b. As the rotor magnet 18 rotates, these rotating parts rotate integrally. A thin wiring board 25 is provided on the back surface (first rotation yoke 22 side) of the first stator coil 21 for wiring the coil terminal, the terminal of the sensor 40, and the like. 35 is the terminal drawer part. The second motor provided on the lower surface side of the fixed base 3 has almost the same structure as the first motor, 4' is a rotating structure, 18' is a second rotor magnet), 21' is a second stator coil, 22' is a second rotating yoke, 25' is a wiring board, 40' is a sensor, 1
1 is a pulley, 5c and 5d are bearings, and 6' is a preload piece.

By inputting the signals of the sensors 40, 40' and the FG multiplied signal to an externally connected electronic circuit and controllingly supplying power to each stator coil 21, 21', each rotor magnet 18.18
' generate rotational driving force independently to rotate each rotating body independently. Each sensor 4Q, 4Q' is each rotor magnet)
It detects the magnetic pole rotation position of 18.18', and a Hall element or the like is suitable. In this structure, the FG of the second motor is
It is assumed that the stator coil 21' is formed of a patterned conductor or the like on the surface of the wiring board 25', and power is generated by changes in the magnetic field of the second rotor magnet 18'. The speed of both the first motor and the second motor is detected from each FG multiplier signal, and constant speed control is performed to a predetermined target speed. FG board 2 in the first motor
If a magnetic material such as a thin iron plate is fixed to the lower part of the FG, the output voltage of the FG can be increased. The stator coils 21, 21' may be sheet-like coils in which a coil conductor is formed in a pattern by plating or etching, or wire-wound coils formed by winding conductive wire. In the case of a wire-wound coil, a structure in which the planar rigidity of the coil is increased by using plastic molding technology etc. is practical for this structure.

According to the structure of this embodiment.

(1) Since two motors are independently configured on the fixed shaft 1, two types of rotational power can be easily extracted independently. Furthermore, the space occupied by the entire power transmission system including the driven part (load part) can be reduced, allowing a compact set to be constructed.

(2) Due to the fixed shaft structure, there is little rotational vibration and uneven rotation can be achieved. Eliminates torsional vibration of the shaft.

(3) Both the first motor and the second motor include a yoke 22.22' sandwiching the air-core stator coil 21.21' and facing the rotor magnet magnetic poles t-the rotor magnet 18
．． Since it is paired with 18' and rotated integrally, iron loss in the stator can be eliminated and motor efficiency can be improved. Also, the attraction force of rotor magnet) 18.18' is yoke 22.2, respectively.
2' and does not act at all on the bearings 5g, 5b, 5c, and 5d, the load on each bearing can be significantly reduced, friction loss during rotation can be reduced, and motor efficiency can be improved. The start-up time can be shortened, assembly work is easy, and bearings are not damaged. Since troubles such as bearing preload waves can be eliminated, the bearing preload value can be significantly reduced, and from this point of view, friction can also be reduced. Furthermore, cogging torque caused by the rotor magnet can also be eliminated, resulting in low rotational unevenness.

(4) Since the structure is such that the yoke 22.22'' and the FG magnet 51 are rotated, rotational inertia can be increased, and controllability can also be improved from this point of view, making it possible to reduce unevenness in rotation.

(5) Since the electromagnetic parts of the first and second motors are arranged close to each other on the shaft 1, magnetic leakage can be easily prevented.

(6) Since the shaft and fixed base can be shared between two monitors, the number of parts and assembly man-hours can be reduced, resulting in low cost and high accuracy.

(7) Setting up test drive machines, jigs, etc. for dynamic balancing of rotating parts is simple and easy.

(8) When decelerating the load rotating body, one motor is used at relatively high speed rotation, so the FG signal rate per motor rotation can be lowered. Therefore, the number of magnetic pole divisions of the FG magnet and the number of FGA turn conductors on the FG board can be reduced to improve the accuracy of the generated FG signal. Furthermore, since the rotational inertia in terms of the load shaft can be increased, the accuracy of the upper FG signal is improved, thereby improving servo performance and reducing rotational unevenness.

FIG. 2 is a diagram showing a second embodiment of the motor of the present invention, in which the first auxiliary rotor magnet 18b and the second auxiliary rotor magnet 18b are replaced with the first and second rotating yokes 22 and 22' in the first embodiment, respectively. This configuration uses a child magnet 186'.

18α is the first main rotor magnet.

18a is the second main rotor magnet 19a 119
b+19'a+19' is each rotor yoke. The first main rotor magnet 18α and the first auxiliary rotor magnet 18b have magnetic poles equally divided into even numbers in each circumferential direction, and have magnetic poles of different polarity facing each other. Similarly, the second main rotor magnet 18α and the second auxiliary rotor magnet 186
′ also has magnetic poles of different polarity facing each other.

According to the structure of this embodiment, in addition to the effects of the first embodiment described above, (1) the magnetic poles of the two magnets are made to face each other so that they have different polarities across the air-core stator coil; By shortening the magnetic path length of the magnetic circuit formed between the magnetic poles, the permeance coefficient can be increased, and as a result, the amount of magnetic flux linked to the stator coil can be significantly increased, and the motor constant can be increased to generate large torque. Furthermore, a predetermined amount of magnetic flux can be easily obtained even by using a low-cost, low-magnetic-energy magnet.

(2) The uniformity of the magnetic field distribution between the magnetic poles in the circumferential direction, radial direction, and axial direction can be increased, and the ripples of the generated torque can be reduced.

FIG. 3 shows a third embodiment of the motor of the present invention, which has a structure in which a fixing member 60 is further fixed on the upper part of the fixed pace 3, a third motor stator is attached to this, and a third motor is added. be. Similar to the first and second motors at the bottom, this third motor also has an air-core stator coil 21# sandwiched between the rotor magnet 1 and the rotor magnet 1.
It has a pair of rotors consisting of an 8# and a rotating yoke 22'. 40# is a sensor.

25# is a wiring board, 11a is a pulley, and 5., 5f is a bearing. According to the structure of this embodiment, in addition to the first effect of the first embodiment, there is a new effect that one more rotational output can be obtained independently.

FIG. 4 is a diagram showing a fourth embodiment of the motor of the present invention.

As the first motor, a paired rotor motor consisting of a first rotor magnet 18 and a first rotating yoke 22 sandwiching a first stator coil 21 is used, and as a second motor, a second rotor motor is used.
The stator coil 22 is sandwiched between the second main rotor magnet 18
; and a second auxiliary rotor magnet 18b'. A belt 150 is connected to the second motor's boot 1 and connected to a load pulley 160 to drive it. 100 is a load rotating shaft, 170 is a load rotating body, 50 is a bearing housing part,
6, 6 are bearing preload pieces. According to the structure of this embodiment,
There is an advantage that the motor specifications such as motor constants can be easily changed to correspond to the rotational speed, torque value, etc. of the load.

FIG. 5 shows a fifth embodiment of the motor of the present invention, in which grooves 71a, 71A, and 71c for bearing rolling elements (balls) are provided on the outer shaft of the shaft 1 as the bearings of the first motor and the second motor.

71d is provided and combined with the outer ring portion 75α, or 75C, and 75d. The structure of the motor electromagnetic section is almost the same as that of the first embodiment.

According to the structure of this embodiment.

(11) Since the outer diameter of the outer ring of the bearing can be made smaller compared to a structure using a conventional ball bearing, the dimensions of the motor, etc. can be made smaller.

(2) Also, since the rolling pitch circle diameter of the balls can be made smaller, bearing vibration can be reduced.

(3) Furthermore, since a material with high rigidity and hardness such as bearing steel is used as the shaft material, the shaft diameter can be made thinner, and from this point of view, it is also possible to achieve a smaller size and lower friction.

(4) Since the structure does not use an inner ring, it is possible to greatly improve the assembly accuracy such as the runout accuracy of the rotating structure 4 with respect to the axis 1.

(5) Since the shaft and the bearing are integrated, it is possible to improve first-class workability by eliminating the process of managing and selecting fit tolerances between the shaft and the bearing in the case of conventional ball bearings.

(6) It has the first effect of being able to reduce costs. Other effects are the same as in the above embodiments.

FIG. 6 is a diagram showing a sixth embodiment of the present invention, which is a structural example in which a fixed shaft 1 is used and the shaft diameter is changed between its upper and lower parts. The relatively large first motor engages its rotating portion with the thick shaft portion 1a, while the small second motor engages its rotating portion with the thin shaft portion 1b. According to this structure, the motor size can be freely configured from small to large and can be optimized to meet the purpose.

FIG. 7 shows another example of the structure of the fixed shaft according to the present invention, in which two shafts are fixed concentrically to the fixed base 6 with a length of 1.1' ft. According to this structure, even if shafts 1 and 1' having short shaft lengths are used, the same shaft structure as in the first to sixth embodiments can be obtained.

The above embodiments all have a structure in which a plurality of flat brushless motors are arranged on the same axis, but there are also structures in which this thin cylindrical brushless motor or a combination of motors of other types other than brushless motors are used. A structure using a pair of rotors having a structure in which a stator coil is sandwiched between one or more of a plurality of motors arranged in a shape to form a magnetic circuit may also be used.

FIG. 8 is a seventh embodiment of the present invention, and is a diagram of an embodiment of a cylindrical motor. A cylindrical stator coil 21.21' is sandwiched between a rotor magnet 18.18' and a rotating yoke 22°22.
′ is arranged. According to the structure of this embodiment, in addition to being able to reduce the motor diameter, the stator coils 21 and 21' can be assembled in combination with the motor rotor with the stator coils 21 and 21' fixed on the fixed pace s in advance, so that assembly, disassembly, adjustment, etc. Easy to do.

In the structures of the various embodiments described above, the stator coil is an air-core coil that does not contain a magnetic material, but there are other examples.

A part of the stator coil contains a magnetic material to create a weak attractive force between it and the rotor magnet, and two magnets (main rotor magnet, auxiliary rotor magnet) are used as the rotor. ) with their magnetic poles facing each other, in addition to the combination of the different-polarity magnetic pole opposing structure and the air-core stator coil described in the example, the different-polarity magnetic pole opposing structure and a part of the structure may be partially laminated with magnetic material. , or a combination configuration with a stator coil of the structure containing it.

A combination configuration of a same-polarity magnetic pole facing structure and an air-core stator coil or a stator coil having a magnetic material inside is also within the scope of the present invention.

〔Effect of the invention〕

According to the invention.

(1) Since two or more rotors can be configured independently within the same shaft, rotational power of two or more rotors can be obtained at the same time, and the entire structure including the load can be made smaller and lighter. Therefore, a small, lightweight and compact set can be realized.

(2) Due to the fixed shaft structure, there is little vibration of the rotating body and rotation is stable.

(3) A yoke (rotating yoke) sandwiching the stator coil and facing the magnetic poles of the rotor magnet or a second rotor magnet paired with the rotor magnet and rotated integrally eliminates iron loss and greatly increases remotor efficiency. can be improved. Furthermore, since the attraction force of the rotor magnet does not act on the bearing that supports the rotating body, the rotational friction of the bearing can be significantly reduced, and efficiency can also be improved from this point of view. Starts up quickly too. Furthermore, assembly work is easy and the bearings are not damaged by suction force or the like. Additionally, cogging torque caused by the rotor magnet can be eliminated, resulting in low rotational unevenness.

(4) Since the inertia of the rotor can be increased, rotational unevenness can also be reduced from this point of view.

(5) Since a plurality of motor electromagnetic parts are arranged together on the same straight line, magnetic leakage can be easily prevented.

(6) Costs can be reduced because the number of parts and assembly man-hours can be reduced.

(7) Since the structure has each rotating part on the same linear axis, there is no need to replace testing machines, jigs, etc. during dynamic balancing work of the rotating parts, allowing efficient work.

(8) When using this motor to decelerate and rotate a load rotating body, the motor speeds up, so the speed control signal frequency per rotation of the motor can be lowered, signal accuracy can be increased, and rotational inertia converted to the load shaft can be increased. Excellent effects such as improved servo performance and less uneven rotation of the loaded rotating body can be obtained.

[Brief explanation of drawings]

FIG. 1 is a diagram showing a first embodiment of the motor of the present invention, FIG. 2 is a diagram of a second embodiment of the same, and FIG. 3 is a diagram of a fifth embodiment of the same. Fig. 4 is a diagram of the fourth embodiment, Fig. 5 is a diagram of the fifth embodiment, Fig. 6 is a diagram of the sixth embodiment, Fig. 7 is a diagram of another embodiment of the shaft fixing method, and Fig. 8 is a diagram of the sixth embodiment. FIG. 7 is a diagram of a seventh embodiment.

Claims (1)

[Claims] 1. Equipped with a plurality of motor rotors concentrically and independently rotatably engaged around a fixed central axis, at least one of the rotors sandwiching a stator coil between a rotor magnet and a rotating yoke. , or a motor having a paired rotor configuration consisting of a combination of a first rotor magnet and a second rotor magnet.