An induction powered moving coil oscillating motor

Abstract

The present invention discloses an induction-powered moving coil oscillation motor, comprising a hollow annular iron core, and an inner circle DC magnetic pole, an outer circle DC magnetic pole, a front inner circle stator coil, a front outer circle stator coil, a rear inner circle stator coil and a rear outer circle stator coil, all of which are arranged in a hollow annular cavity of the annular iron core, and a moving coil is arranged between the inner circle DC magnetic pole and the outer circle DC magnetic pole; the stator coil supplies power to the moving coil by electromagnetic induction, and there is no electrical connection between the stator coil and the moving coil, which not only reduces the motion mass and improves the driving efficiency, but also avoids the problems of unreliable power supply, fatigue aging and the like that may be caused by contact power supply. The AC magnetic field energy of the stator coil is coupled and transferred to the moving coil through the annular iron core magnetic circuit, rather than through the conventional air magnetic circuit coupling, thereby reducing the leakage magnetic flux, increasing the coupling coefficient between the stator coil and the moving coil, and improving the efficiency of power supply to the moving coil.

Description

Technical Field

[0001] The invention belongs to the technical field of motors and systems thereof, and in particular relates to an induction-powered moving-coil oscillating motor. Background Art

[0002] Linear motors are electromechanical energy conversion devices that convert electrical energy directly into mechanical energy of load linear motion. Since there is no need for an intermediate conversion mechanism from rotational motion to linear motion (such as chain-gear mechanism, wire rope-hub mechanism, belt-drive wheel mechanism, screw-gear mechanism, etc.), linear motors have the characteristics of simple structure, high transmission efficiency, fast movement speed, high operating reliability, low noise, good environmental adaptability, etc., and play an important role in national economic production and life.

[0003] According to the different working mechanisms, linear motors can be divided into two categories: one-way linear motors and reciprocating linear motors. Reciprocating linear motors are linear motors that use electromagnetic force to drive the rotor and the load to make reciprocating linear motion at a certain frequency, also known as oscillation motors. According to the working principle, oscillation motors can be divided into linear induction oscillation motors and linear synchronous oscillation motors.

[0004] The basic structure of the linear induction oscillation motor is a combination of two single-pass linear induction motors, one for forward acceleration and reverse braking, and one for forward braking and reverse acceleration. Its disadvantages are: high heat and loss, low efficiency, large magnetic leakage, and low power factor. Therefore, except for low-frequency long-stroke air compressors, it is generally rarely used.

[0005] As the name implies, the linear synchronous oscillation motor has a mover that moves synchronously with the magnetic field. The oscillation frequency of the mover is strictly controlled by the frequency of the AC power supply, and there is no slip rate. Therefore, it has the characteristics of high output, low loss, and high efficiency. According to the type of mover, the linear synchronous oscillation motor can be divided into a moving coil oscillation motor, a moving iron core oscillation motor, and a moving permanent magnet oscillation motor. Due to the high density of iron and permanent magnets, the mover mass of the moving iron core oscillation motor and the moving permanent magnet oscillation motor is large, so the oscillation frequency that can be achieved is not high, but the volume is small, and it is generally used in small and medium power, medium and low frequency occasions. The mover of the moving coil oscillation motor is composed of a coil, generally made of lightweight conductive metal materials, and the mover is light in weight, and can achieve a higher movement speed and reciprocating frequency, so it is widely used in equipment such as speakers and audio testers.

[0006] The working principle of the moving coil oscillating motor is: a stator (usually a permanent magnet) generates a DC magnetic field, and an AC current is passed through the coil as the mover, so that the current-carrying coil reciprocates under the action of the AC Ampere force, and the movement frequency is the same as the current frequency. Since the moving coil oscillating motor only requires the mover to be made of conductive material, the mover coil can be made of lightweight conductive metal (such as aluminum, titanium), which can achieve the effect of reducing the weight of the mover and improving the driving efficiency.

[0007] The main problems faced by traditional moving coil oscillation motors are: (1) The problem of power supply for the moving coil: Generally, flexible wires or contact slides are used to power the moving coil. If wires are used, part of the wire mass must also be included in the moving mass of the moving coil, which reduces the driving efficiency. In addition, the insulation layer and joints of the wires that move back and forth for a long time are prone to fatigue damage. If contact slides are used, the friction generated during movement will also reduce efficiency. At high speeds, sparks, ablation, poor contact and other problems will also occur. (2) The problem of moving coil inductance: The moving coil has a certain self-inductance. When AC is passed through it, it will generate inductive reactance, and the inductive reactance is generally greater than the resistance. This means that in order to obtain a certain moving coil current, a higher supply voltage is required, thereby increasing the burden on the power supply capacity. Summary of the invention

[0008] The purpose of the present invention is to provide an induction-powered moving-coil oscillation motor to address the defects of the prior art, which can effectively solve the problems of traditional moving-coil oscillation motors such as unreliable operation, reduced efficiency, and high power supply capacity requirements caused by powering the mover.

[0009] To achieve the above-mentioned purpose, the induction-powered moving-coil oscillating motor designed in the present invention comprises a hollow annular core, and an inner-ring DC magnetic pole, an outer-ring DC magnetic pole, a front inner-ring stator coil, a front outer-ring stator coil, a rear inner-ring stator coil and a rear outer-ring stator coil, all of which are arranged in the hollow annular cavity of the annular core, a moving coil is arranged between the inner-ring DC magnetic pole and the outer-ring DC magnetic pole, and the moving coil itself forms a closed conductor along the circumference of the annular core;

[0010] The inner circle DC magnetic poles and the outer circle DC magnetic poles are arranged front-to-back symmetrically with respect to the central axis plane of the annular core perpendicular to the moving direction of the mover coil, and the inner circle DC magnetic poles and the outer circle DC magnetic poles are arranged radially inwardly and outwardly symmetrically with respect to the conductor surface of the mover coil;

[0011] The front inner stator coil and the rear inner stator coil, as well as the front outer stator coil and the rear outer stator coil are all arranged front-to-back symmetrically about the central axis plane of the annular core perpendicular to the direction of movement, and the front inner stator coil and the front outer stator coil, as well as the rear inner stator coil and the rear outer stator coil are respectively arranged radially symmetrically inside and outside about the conductor surface of the mover coil.

[0012] Furthermore, the inner ring DC magnetic poles and the outer ring DC magnetic poles are arranged opposite to each other as opposite poles, and the sizes of the pole shoe surfaces of the inner ring DC magnetic poles and the outer ring DC magnetic poles are much larger than the distance between the opposite poles.

[0013] Furthermore, the inner ring DC magnetic pole is in close contact with the inner ring surface of the hollow annular cavity in the annular core, and the outer ring DC magnetic pole is in close contact with the outer ring surface of the hollow annular cavity in the annular core.

[0014] Furthermore, the front inner ring stator coil is tightly attached to the front side wall and inner ring surface of the hollow annular cavity and is insulated from the annular iron core, the front outer ring stator coil is tightly attached to the front side wall and outer ring surface of the hollow annular cavity and is insulated from the annular iron core, the rear inner ring stator coil is tightly attached to the rear side wall and inner ring surface of the hollow annular cavity and is insulated from the annular iron core, and the rear outer ring stator coil is tightly attached to the rear side wall and outer ring surface of the hollow annular cavity and is insulated from the annular iron core.

[0015] Furthermore, the annular iron core is evenly divided into a number of iron core units along the circumferential direction along a cross section perpendicular to the movement direction of the moving coil, and the number of sections of the iron core units is consistent with the number of phases of the stator coil; there is a gap between each two adjacent sections of the iron core units, and the gap size between each two adjacent sections of the iron core units is much smaller than the cross-sectional size of the annular iron core.

[0016] Furthermore, the inner ring DC magnetic poles and the outer ring DC magnetic poles are divided into a number of radially magnetized sector-shaped magnetic poles along the cross section perpendicular to the movement direction of the mover coil along the circumferential direction, and the number of segments, gaps and positions of the sector-shaped magnetic poles are the same as those of the core unit.

[0017] Compared with the prior art, the present invention has the following advantages:

[0018] 1. The stator coil in the present invention supplies power to the mover coil by electromagnetic induction, and there is no electrical connection between the stator coil and the mover coil, which not only reduces the motion mass and improves the driving efficiency, but also avoids the problems of unreliable power supply, fatigue and aging that may be caused by contact power supply;

[0019] 2. The mover coil in the present invention has its own inductance that couples the magnetic field energy generated by the stator coil to the mover side. The inductance acts as the power supply on the mover side, rather than the inductive reactance in the traditional moving coil oscillation motor. At this time, the load on the mover side can be considered to be only the coil resistance, thereby greatly improving the power factor and reducing the requirements for the voltage and capacity of the AC power supply;

[0020] 3. The present invention couples the AC magnetic field energy of the stator coil to the mover coil through the annular iron core magnetic circuit, rather than through the conventional air magnetic circuit coupling, thereby reducing magnetic leakage, increasing the coupling coefficient between the stator coil and the mover coil, and improving the efficiency of power supply to the mover coil;

[0021] 4. The annular iron core in the present invention is both an AC magnetic circuit coupling path and a DC magnetic circuit coupling path, connecting the DC magnetic poles on both sides of the mover coil, ensuring efficient coupling of the DC magnetic field, reducing DC leakage flux, and improving driving efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 A schematic cross-sectional structure diagram of the induction powered moving coil oscillating motor of the present invention;

[0023] Figure 2 It is a three-dimensional structural schematic diagram of the moving coil oscillation motor of the present invention;

[0024] Figure 3 for Figure 2 Schematic diagram of the DC magnetic pole arrangement structure;

[0025] Figure 4 for Figure 2 Schematic diagram of the stator coil arrangement structure;

[0026] Figure 5 It is a schematic diagram of the AC magnetic circuit coupling path of the moving coil oscillation motor of the present invention;

[0027] Figure 6 It is a schematic diagram of the DC magnetic circuit coupling path of the moving coil oscillation motor of the present invention. DETAILED DESCRIPTION

[0028] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0029] like Figure 1 , 2 The induction powered moving coil oscillating motor shown in the figure comprises a hollow annular iron core 3, and an inner circle DC magnetic pole 1, an outer circle DC magnetic pole 2, a front inner circle stator coil 4, a front outer circle stator coil 5, a rear inner circle stator coil 6 and a rear outer circle stator coil 7, all arranged in the hollow annular cavity of the annular iron core 3, and a mover coil 8 is arranged between the inner circle DC magnetic pole 1 and the outer circle DC magnetic pole 2. The iron core 3 is arranged at the outermost layer of the motor as a coupling path shared by the AC magnetic flux and the DC magnetic flux, and covers the DC magnetic pole, the stator coil and the mover coil. In this embodiment, the moving direction of the mover coil 8 is the front and rear direction.

[0030] Combination Figure 3 , 6 As shown, the inner ring DC magnetic pole 1 and the outer ring DC magnetic pole 2 are arranged front-to-back symmetrically with respect to the central axis plane of the annular core 3 perpendicular to the moving direction of the mover coil 8 (i.e., as shown by the X axis in the figure), and the inner ring DC magnetic pole 1 and the outer ring DC magnetic pole 2 are arranged front-to-back symmetrically with respect to the conductor surface of the mover coil 8 (i.e., along the moving direction, Figure 6The inner ring DC magnetic pole 1 and the outer ring DC magnetic pole 2 are arranged symmetrically inside and outside along the radial direction (as shown by the Y1 axis and the Y2 axis in the middle). This arrangement can make the radial DC magnetic field strength at the position of the mover coil 8 reach the maximum value, and during the reciprocating motion of the mover, the magnetic field strength is approximately a constant, which is easy to achieve motion control. The inner ring DC magnetic pole 1 and the outer ring DC magnetic pole 2 are arranged relative to each other in the form of opposite poles. The pole shoe surface sizes of the inner ring DC magnetic pole 1 and the outer ring DC magnetic pole 2 are much larger than the distance between the opposite poles, so that an approximately uniform DC magnetic field is formed in the center area of ​​the pole shoe surface. In this embodiment, the inner ring DC magnetic pole 1 is in close contact with the inner ring surface of the hollow annular cavity of the annular core 3, and the outer ring DC magnetic pole 2 is in close contact with the outer ring surface of the hollow annular cavity of the annular core 3. The inner ring DC magnetic pole 1 and the outer ring DC magnetic pole 2 can be designed as an integrated annular core 3, and the DC magnetic flux and the AC magnetic flux share the iron core as a common coupling path.

[0031] In addition, the mover coil 8 itself forms a closed conductor along the circumference of the annular core 3. According to the Lorentz force law, the mover coil 8 cuts the DC magnetic field and generates a motional electromotive force when moving, and then bears the Ampere force opposite to the direction of movement. The Ampere force can partially replace the mechanical spring and provide the mover coil with a restoring force of simple harmonic vibration (such as Figure 6 f restore In this embodiment, the material of the mover coil 8 can be a metal with a high unit mass conductivity (which can be understood as the ratio of volume conductivity to density), such as aluminum.

[0032] Combination Figure 4 , 5 As shown, the front inner stator coil 4 and the rear inner stator coil 6, the front outer stator coil 5 and the rear outer stator coil 7 are all perpendicular to the movement direction (such as Figure 5 The central axis of the rotor 8 is arranged symmetrically front to back, and the symmetrically arranged stator coils have the same number of turns and current values. On the one hand, this arrangement allows the electromagnetic forces of the stator coils on the front and rear sides of the rotor coil 8 to approximately cancel each other out during the movement of the rotor coil 8, thereby avoiding interference with the movement of the rotor. On the other hand, the total mutual inductance coupling coefficient between the stator coil and the rotor coil can reach a maximum value, and is approximately a constant during the movement of the rotor. The front inner stator coil 4 and the front outer stator coil 5, and the rear inner stator coil 6 and the rear outer stator coil 7 are respectively arranged with respect to the conductor surface of the rotor coil 8 (i.e., along the direction of movement, Figure 5The stator coils are symmetrically arranged radially inside and outside (as shown by the Y1 axis and the Y2 axis), and the symmetrically arranged stator coils have the same number of turns and current values. This arrangement can make the total mutual inductance coupling coefficient between the stator coil and the mover coil 8 reach a maximum value, and it is approximately a constant during the movement of the mover, thereby improving the coupling efficiency between the stator coil and the mover coil 8. In this embodiment, the annular core 3 forms a circumferential closed loop around the stator coil, and the front inner ring stator coil 4 is tightly attached to the front side wall and inner ring surface of the hollow annular cavity while being insulated from the annular core 3, the front outer ring stator coil 5 is tightly attached to the front side wall and outer ring surface of the hollow annular cavity while being insulated from the annular core 3, the rear inner ring stator coil 6 is tightly attached to the rear side wall and inner ring surface of the hollow annular cavity while being insulated from the annular core 3, and the rear outer ring stator coil 7 is tightly attached to the rear side wall and outer ring surface of the hollow annular cavity while being insulated from the annular core 3. Therefore, the alternating magnetic flux generated by the alternating current in the stator coil forms a closed magnetic circuit along the annular core, and the leakage magnetic flux is extremely small, so that the stator coil and the mover coil are nearly fully coupled, which greatly improves the efficiency of the induction power supply.

[0033] Again Figure 2 As shown, the annular core 3 is evenly divided into several core units along the cross section perpendicular to the moving direction of the moving coil 8 along the circumferential direction. There is a gap or opening between each two adjacent core units for stator coil outlet and mechanical connection between the moving coil and the external moving load. The gap size between each two adjacent core units should be much smaller than the cross-sectional size of the annular core (preferably less than 1 / 10 of the cross-sectional size of the annular core) to minimize magnetic leakage. The number of core units is consistent with the number of phases of the stator coil to facilitate the outlet of the stator coil. The front inner stator coil 4, the front outer stator coil 5, the rear inner stator coil 6 and the rear outer stator coil 7 are supplied with alternating current by an external power supply, generating an AC magnetic circuit in the annular core. The AC magnetic flux located on the inner side of the annular core induces eddy currents closed along the moving coil in the moving coil 8, thereby realizing that the stator coil supplies power to the moving coil in a non-contact induction manner.

[0034] The inner ring DC magnetic pole 1 and the outer ring DC magnetic pole 2 can adopt an integral ring shape without segments, but from the perspective of reducing manufacturing difficulty and facilitating magnetization, the inner ring DC magnetic pole 1 and the outer ring DC magnetic pole 2 are both divided into a number of radially magnetized sector-shaped magnetic poles along the cross section perpendicular to the movement direction of the mover coil 8 along the circumferential direction. The number of segments, gaps, and positions of the sector-shaped magnetic poles are the same as the number of segments, gaps, and positions of the core unit, which facilitates the integrated design and installation of the DC magnetic poles and the annular core.

[0035] Again Figure 5The AC magnetic circuit coupling path (cross-sectional view) of the moving coil oscillating motor of the present invention is shown in FIG. 1 . According to Ampere's circuit theorem, the stator coil carrying AC current surrounded by the annular core generates an annular AC magnetic circuit inside the annular core. According to Faraday's law of electromagnetic induction, the inner side of the annular core ( Figure 5 The AC magnetic flux in the CyI induces eddy currents in the rotor coil, thereby realizing that the stator coil supplies power to the rotor coil by induction. Since the AC magnetic flux forms a circumferential closed magnetic circuit along the annular core, and the stator coil is arranged close to the annular core, the leakage magnetic flux is very small, and the stator coil and the rotor coil are almost fully coupled, which greatly improves the efficiency of induction power supply. Figure 5 CyI) is understood as the core of the transformer, and the rotor coil can be regarded as the secondary winding on the core. Therefore, the method of inductively supplying power to the mover coil by the stator coil of the present invention can be called "transformer power supply".

[0036] The specific embodiments described herein are merely examples of the spirit of the present invention. Those skilled in the art may make various modifications or additions to the specific embodiments described or replace them in similar ways, but they will not deviate from the spirit of the present invention or exceed the scope defined by the appended claims.

Claims

1. An induction powered moving coil oscillating motor, characterized in that: The invention comprises a hollow annular iron core (3), and an inner ring DC magnetic pole (1), an outer ring DC magnetic pole (2), a front inner ring stator coil (4), a front outer ring stator coil (5), a rear inner ring stator coil (6) and a rear outer ring stator coil (7) all arranged in a hollow annular cavity of the annular iron core (3); a mover coil (8) is arranged between the inner ring DC magnetic pole (1) and the outer ring DC magnetic pole (2); the mover coil (8) itself forms a closed conductor along the circumference of the annular iron core (3); The inner ring DC magnetic pole (1) and the outer ring DC magnetic pole (2) are arranged front-to-back symmetrically with respect to the central axis plane of the annular iron core (3) perpendicular to the moving direction of the mover coil (8), and the inner ring DC magnetic pole (1) and the outer ring DC magnetic pole (2) are arranged radially inwardly and outwardly symmetrically with respect to the conductor surface of the mover coil (8); The front inner stator coil (4) and the rear inner stator coil (6), the front outer stator coil (5) and the rear outer stator coil (7) are all arranged front-to-back symmetrically with respect to the central axis plane of the annular core (3) perpendicular to the direction of movement, and the front inner stator coil (4) and the front outer stator coil (5), the rear inner stator coil (6) and the rear outer stator coil (7) are respectively arranged radially inwardly and outwardly symmetrically with respect to the conductor surface of the mover coil (8); The inner ring DC magnetic pole (1) and the outer ring DC magnetic pole (2) are arranged opposite to each other as opposite poles, and the sizes of the pole shoe surfaces of the inner ring DC magnetic pole (1) and the outer ring DC magnetic pole (2) are much larger than the distance between the opposite poles.

2. The induction powered moving coil oscillating motor according to claim 1, characterized in that: The inner ring DC magnetic pole (1) is in close contact with the inner ring surface of the hollow annular cavity of the annular iron core (3), and the outer ring DC magnetic pole (2) is in close contact with the outer ring surface of the hollow annular cavity of the annular iron core (3).

3. The inductively powered moving coil oscillating motor according to claim 1, characterized in that: The front inner stator coil (4) is in close contact with the front side wall and inner ring surface of the hollow annular cavity and is insulated from the annular iron core (3); the front outer stator coil (5) is in close contact with the front side wall and outer ring surface of the hollow annular cavity and is insulated from the annular iron core (3); the rear inner stator coil (6) is in close contact with the rear side wall and inner ring surface of the hollow annular cavity and is insulated from the annular iron core (3); and the rear outer stator coil (7) is in close contact with the rear side wall and outer ring surface of the hollow annular cavity and is insulated from the annular iron core (3).

4. The inductively powered moving coil oscillating motor according to claim 1, characterized in that: The annular iron core (3) is evenly divided into a plurality of iron core units along a cross section perpendicular to the moving direction of the moving coil (8) along the circumferential direction, and the number of the iron core units is consistent with the number of phases of the stator coil; there is a gap between each two adjacent iron core units, and the size of the gap between each two adjacent iron core units is much smaller than the cross-sectional size of the annular iron core.

5. The induction powered moving coil oscillating motor according to claim 1, characterized in that: The inner ring DC magnetic pole (1) and the outer ring DC magnetic pole (2) are divided into a plurality of radially magnetized sector-shaped magnetic poles along a cross section perpendicular to the moving direction of the mover coil (8) along the circumferential direction, and the number of sectors, gaps and positions of the sector-shaped magnetic poles are the same as those of the core unit.

Images