Electrically-excited movable iron core type linear oscillation motor

Abstract

The invention discloses an electro-magnetic movable iron core type linear oscillation motor, which belongs to the field of linear oscillation motor design and comprises a stator iron core, an excitation winding, an armature winding, a rotor iron core, a shaft, a linear bearing and a resonance plate spring. The stator cores are symmetrically distributed on two sides of the motion plane of the mover, and one armature winding and one excitation winding are respectively wound on the stator core on each side; and the shaft passes through the two sides of the automatic sub-iron core and is supported by the linear bearing and the resonance plate spring. The size of an excitation magnetic field can be changed by adjusting the current of the excitation winding, and meanwhile, the motor can realize linear reciprocating motion by matching with power supply of the armature winding. According to the linear oscillation motor, the resonant frequency can be freely adjusted in a wide range, and the linear oscillation motor has the advantages of being adjustable in maximum efficiency working point, high in economical efficiency and the like.

Description

Technical Field

[0001] The present invention belongs to the field of linear oscillation motor design, and more specifically, relates to an electrically excited moving iron core type linear oscillation motor. Background Art

[0002] Traditional rotary compressors have many friction points and low efficiency. However, linear compressors driven by linear oscillation motors can reduce friction points, improve efficiency and reduce the overall size of the compressor because they eliminate intermediate conversion structures such as crank connecting rods.

[0003] The linear oscillation motor driving the linear compressor works on the principle of forced simple harmonic vibration and has maximum efficiency at the resonant frequency point, so it usually runs at the resonant frequency point, which is determined by the spring elastic coefficient, the equivalent magnetic spring elastic coefficient in the motor, and the mass of the mover. The existing linear oscillation motor adopts the structure of a permanent magnet motor. When the motor design is completed, the properties of the spring and permanent magnet are determined. At this time, the motor usually runs near a constant resonant frequency point. When there is a need to change the resonant frequency, usually only the spring can be replaced or a new motor can be redesigned, which makes the motor not very expandable and applicable. Summary of the invention

[0004] In view of the defects and improvement needs of the prior art, the present invention provides an electrically excited moving iron core type linear oscillation motor, which aims to solve the problems of the existing linear oscillation motor in practical engineering applications, such as the non-adjustable excitation magnetic field and the difficulty in adjusting the resonant frequency. The motor of the present invention can adjust the excitation magnetic field within a large range, and the armature magnetic field can adjust the equivalent magnetic spring coefficient, thereby realizing the adjustment of the resonant frequency.

[0005] To achieve the above-mentioned purpose, the present invention provides an electrically excited moving iron core type linear oscillation motor, comprising: a stator core, an excitation winding, an armature winding, a mover core, a shaft, a linear bearing, and a resonant plate spring; the stator core is symmetrically distributed on both sides of the moving plane of the mover core, and each side of the stator core is respectively wound with an armature winding and an excitation winding; the shaft passes through both sides of the mover core and is supported by linear bearings and resonant plate springs; the size of the excitation magnetic field can be changed by adjusting the size of the excitation winding current, and at the same time, the motor can achieve linear reciprocating motion by cooperating with the armature winding to supply power.

[0006] Furthermore, the mover core and the shaft together constitute the mover.

[0007] Furthermore, the excitation windings are wound around the corresponding stator cores along the normal direction, and the winding directions of the two excitation windings are symmetrical and the same with respect to the motion plane of the mover.

[0008] Furthermore, direct current is passed into the excitation winding to establish an excitation magnetic field for the motor.

[0009] Furthermore, the armature windings are wound longitudinally across the corresponding stator cores, and the winding directions of the two armature windings are symmetrical and the same with respect to the moving plane of the mover.

[0010] Furthermore, alternating current is passed into the armature winding to generate an armature magnetic field, thereby driving the motor to achieve reciprocating motion.

[0011] Furthermore, the field winding and the armature winding are both in the form of concentrated windings.

[0012] Furthermore, the stator core is formed by laminating a minimum laminating unit in a transverse direction, and the minimum laminating unit is made of silicon steel sheets.

[0013] Furthermore, both ends of the shaft are provided with external threads, which can be connected in series in multiple stages or connected to loads and displacement sensors through nuts.

[0014] In general, the above technical solutions conceived by the present invention can achieve the following beneficial effects compared with the prior art: (1) The linear oscillation motor of the present invention adopts excitation winding excitation. This excitation method has the characteristic of freely adjusting the excitation magnetic field. The excitation magnetic field will produce a positioning force on the rotor core. The positioning force increases linearly with the position of the rotor, forming an equivalent magnetic spring. Therefore, the spring elastic coefficient can be adjusted by adjusting the excitation current, so that the motor has the characteristic of variable resonance frequency over a wide range.

[0015] (2) When the excitation winding of the present invention is energized to generate an excitation magnetic field, in addition to being able to generate an equivalent magnetic spring on the mover, it can also cooperate with the armature winding to generate a periodic electromagnetic thrust on the mover core.

[0016] (3) The linear oscillation motor of the present invention adopts a moving iron core structure. The mover of this structure is made of soft magnetic materials such as silicon steel sheets, etc., which has high reliability and long motor life. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a three-dimensional overall schematic diagram of an electrically excited moving iron core type linear oscillation motor of the present invention; Figure 2 It is a schematic diagram of the magnitude of the positioning force generated by the excitation magnetic field on the motor mover when the mover of the electric excitation moving iron core type linear oscillation motor of the present invention is in a balanced position; Figure 3 It is a schematic diagram of the direction of the positioning force exerted on the motor mover when the mover of an electrically excited moving iron core type linear oscillation motor of the present invention is in a negative displacement state; Figure 4 It is a schematic diagram of the direction of the positioning force exerted on the motor mover when the mover of an electrically excited moving iron core type linear oscillation motor of the present invention is in a positive displacement state; Figure 5 It is a two-dimensional schematic diagram of a resonant plate spring used in an electrically excited moving iron core type linear oscillation motor of the present invention; Figure 6 It is a three-dimensional schematic diagram of a linear bearing used in an electrically excited moving iron core type linear oscillation motor of the present invention; Figure 7 It is a schematic diagram of the size of an equivalent magnetic spring generated by an electrically excited moving iron core type linear oscillation motor of the present invention under different excitation currents; Among them, 1 is the stator core; 2 is the excitation winding; 3 is the armature winding; 4 is the mover core; 5 is the shaft; 6 is the linear bearing; and 7 is the resonant plate spring. DETAILED DESCRIPTION

[0018] In order to make the purpose, technical scheme and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention. In addition, the technical features involved in each embodiment of the present invention described below can be combined with each other as long as they do not conflict with each other. To achieve the above-mentioned purpose, the present invention adopts the following technical scheme.

[0019] Figure 1 This is a three-dimensional overall schematic diagram of an electrically excited moving iron core linear oscillation motor of the present invention (excluding the resonant plate spring and the linear bearing), see Figure 1 , combined with Figure 2-Figure 7 , the electrically excited moving iron core type linear oscillation motor in an embodiment of the present invention is described in detail.

[0020] See also Figure 1 , this embodiment includes a stator core 1, an excitation winding 2, an armature winding 3, a mover core 4, a shaft 5, a linear bearing 6, and a resonant plate spring 7; the stator core 1 is symmetrically distributed on both sides of the moving plane of the mover core 4, and each side of the stator core 1 is respectively wound with an armature winding 3 and an excitation winding 2, and the shaft 5 passes through both sides of the mover core 4 and is supported by linear bearings 6 and resonant plate springs 7, and the mover core 4 and the shaft 5 together constitute a mover. The size of the excitation magnetic field can be changed by adjusting the size of the excitation winding current, and the motor can achieve linear reciprocating motion by cooperating with the armature winding power supply. The stator core 1 is made of the smallest stacking unit stacked in the transverse direction, and the smallest stacking unit is made of silicon steel sheet material. There are external threads on the outer surface of both ends of the shaft, which can be connected in multiple stages in series or connected to loads and displacement sensors through nuts.

[0021] Combination Figure 1 and Figure 2-Figure 4, the excitation winding 2 is wound along the normal direction on the corresponding stator core 1, and the winding directions of the two excitation windings 2 are symmetrical about the plane of motion of the rotor. The armature winding 3 is wound along the longitudinal direction on the corresponding stator core 1, and the winding directions of the two armature windings 3 are symmetrical about the plane of motion of the rotor. Among them, direct current is passed through the excitation winding 2 to establish an excitation magnetic field for the motor, and alternating current is passed through the armature winding 3 to generate an armature magnetic field to drive the motor to achieve reciprocating motion. Both the excitation winding 2 and the armature winding 3 are concentrated windings. The excitation winding 2 is Figure 2-Figure 4 When the power is on, Figure 2 It shows the situation that the positioning force on the mover is zero when it is in the equilibrium position; Figure 3 It shows the situation that the positioning force on the mover is in the positive direction when it is in the negative stroke position; Figure 4 It shows the situation that the positioning force on the mover is in the negative direction when it is in the positive stroke position.

[0022] Figure 5 A three-dimensional schematic diagram of the resonant plate spring 7 used in the electrically excited moving iron core type linear oscillation motor of the present invention is given. The resonant plate spring 7 comprises three vortex arms, and a small hole for connecting the motor shaft is opened in the middle; Figure 6 A three-dimensional schematic diagram of the linear bearing 6 used in the electro-magnetic moving iron core linear oscillation motor of the present invention is given. The linear bearing 6 is installed on the other side of the motor relative to the resonant plate spring 7. The two cooperate with each other to support the motor. The resonant plate spring 7 adopts an Archimedean spiral plate spring, and the linear bearing 6 adopts a flange linear bearing.

[0023] Figure 7 The schematic diagram of the equivalent magnetic spring size generated by the electric-excited moving-iron-core linear oscillation motor under different excitation currents is given. When the excitation winding is passed through 0, 1 (pu), and 2 (pu) currents, the schematic diagram of the positioning force on the motor is shown. It can be seen that at -x m to x m Within the stroke range, at the same mover position, the magnitude of the positioning force increases with the increase of the excitation current; in addition, at the same excitation current, the positioning force and the mover position maintain a highly linear relationship, satisfying Hooke's law F d = -kx, where F d is the magnitude of the positioning force, and k is the elastic coefficient of the equivalent magnetic spring. Therefore, the positioning force can play the role of an equivalent magnetic spring.

[0024] It can be seen that the invention can adjust the size of the equivalent magnetic spring elastic coefficient of the positioning force by adjusting the excitation current within a large range, thereby indirectly adjusting the resonant frequency. The size of, where k is the total elastic coefficient of the system, is the sum of the elastic coefficient of the equivalent magnetic spring and the elastic coefficient of the leaf spring, and m is the total mass of the mover, so that it can work at the maximum efficiency point under different speed requirements to further reduce energy consumption, which illustrates the correctness and advancement of the theory of the present invention.

[0025] The electrically excited moving iron core type linear oscillation motor of the present invention has the characteristic that the resonant frequency can be freely adjusted, and is particularly suitable for scenarios where it is inconvenient to disassemble the motor in actual engineering.

[0026] It will be easily understood by those skilled in the art that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. An electrically excited moving iron core type linear oscillation motor, characterized in that: include: stator core, field winding, armature winding, mover core, shaft, linear bearing, resonant plate spring; wherein, The stator core is symmetrically distributed on both sides of the moving plane of the mover core, and each side of the stator core is wound with an armature winding and an excitation winding respectively; the shaft passes through both sides of the mover core and is supported by linear bearings and resonant plate springs; the size of the excitation magnetic field is changed by adjusting the size of the excitation winding current, and at the same time, the armature winding is powered to enable the motor to achieve linear reciprocating motion.

2. The electrically excited moving iron core type linear oscillation motor according to claim 1, characterized in that: The mover core and the shaft together constitute the mover.

3. The electrically excited moving iron core type linear oscillation motor according to claim 1, characterized in that: The excitation windings are wound around the corresponding stator cores along the normal direction, and the winding directions of the two excitation windings are symmetrical and the same about the moving plane of the mover.

4. An electrically excited moving iron core type linear oscillation motor according to any one of claims 1 and 3, characterized in that: A direct current is passed through the field winding to establish an excitation magnetic field for the motor.

5. The electrically excited moving iron core type linear oscillation motor according to claim 1, characterized in that: The armature windings are wound longitudinally across the corresponding stator cores, and the winding directions of the two armature windings are symmetrical and the same with respect to the moving plane of the mover.

6. The electrically excited moving iron core type linear oscillation motor according to any one of claims 1 and 5, characterized in that: The armature winding is supplied with alternating current to generate an armature magnetic field, which drives the motor to achieve reciprocating motion.

7. An electrically excited moving iron core type linear oscillation motor according to any one of claims 1, 3 and 5, characterized in that: The field winding and the armature winding are both in the form of concentrated windings.

8. The electrically excited moving iron core type linear oscillation motor according to claim 1, characterized in that: The stator core is formed by stacking the smallest stacking unit in the transverse direction, and the smallest stacking unit is made of silicon steel sheets.

9. The electrically excited moving iron core type linear oscillation motor according to claim 1, characterized in that: The two ends of the shaft are provided with external threads, and are connected to the resonant plate spring or connected in series in multiple stages to connect the load through nuts.

10. The electrically excited moving iron core type linear oscillation motor according to claim 1, characterized in that: The resonant frequency is indirectly adjusted by adjusting the excitation current to adjust the equivalent magnetic spring elastic coefficient of the positioning force; the calculation formula of the resonant frequency is: ； Among them, k is the total elastic coefficient of the system, which is the sum of the elastic coefficient of the equivalent magnetic spring and the elastic coefficient of the leaf spring, and m is the total mass of the mover.

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