A linear motor

Abstract

The present invention discloses a linear motor, which includes an installation mechanism. The installation mechanism is fixedly connected with a plurality of permanent magnet monomers. At least one permanent magnet monomer forms a permanent magnet group, and at least four permanent magnet groups form a permanent magnet row. There are two permanent magnet rows which are distributed in parallel. Three coil groups are arranged between the two permanent magnet rows. The magnetic pole arrangement rule on the same side of all the permanent magnet groups in one of the permanent magnet rows is as follows: the magnetic pole polarity of the first permanent magnet group is N pole, the magnetic pole polarity of the second permanent magnet group is S pole. Starting from the third permanent magnet group, the magnetic pole polarity of the odd-numbered permanent magnet group is the same as that of the previous permanent magnet group, and the magnetic pole polarity of the even-numbered permanent magnet group is opposite to that of the previous permanent magnet group. When the same driving force is output, the present invention uses fewer permanent magnet monomers, reduces the volume of the linear motor, lowers the production cost, improves the utilization efficiency of the permanent magnet monomers, and has strong practicability.

Description

[Technical Field]

[0001] The present invention relates to a linear motor. [Background Art]

[0002] Linear motors are widely used in equipment such as rail transit, machine tools, and amusement facilities. The permanent magnet arrangement structure of existing linear motors generally consists of a plurality of permanent magnet monomers (magnets) with the same specifications arranged side by side to form two parallel permanent magnet columns. The polarities of the opposite permanent magnet monomers between the two permanent magnet columns are opposite, and the polarities of all the permanent magnet monomers on one side of one permanent magnet column are arranged alternately as N poles and S poles. In order to obtain sufficient driving force, existing linear motors need to use a large number of permanent magnets, resulting in low utilization efficiency of permanent magnets, large volume of linear motors, and high production costs. When the output power remains unchanged, the driving force fluctuation range of existing linear motors is relatively large, generally up to 15%, which is not conducive to the normal and stable operation of equipment.

[0003] The present invention is generated based on the above problems. [Summary of the Invention]

[0004] The purpose of the present invention is to address the deficiencies of the prior art and propose a new type of linear motor. Compared with existing linear motors under the same output driving force, the present invention uses a smaller number of permanent magnet monomers, has a smaller overall volume, and lower production costs.

[0005] To solve the above technical problems, the technical solution adopted by the present invention is:

[0006] A linear motor includes an installation mechanism, on which a plurality of permanent magnet monomers with the same specifications are fixedly connected. At least one of the permanent magnet monomers is arranged side by side to form a permanent magnet group. All the permanent magnet monomers in the permanent magnet group with the same polarity of magnetic poles are arranged on the same side to form the N pole and S pole of the permanent magnet group respectively. At least four of the permanent magnet groups are arranged side by side in a straight line to form a permanent magnet column. There are two permanent magnet columns and they are distributed in parallel. The number of permanent magnet groups in each permanent magnet column is an even number. There is a gap between the two permanent magnet columns and they are arranged opposite to each other left and right. Three coil groups capable of moving relative to them are provided between the two permanent magnet columns. The polarities of the opposite magnetic poles between the two permanent magnet columns are opposite. The arrangement rule of the magnetic poles on the same side of all the permanent magnet groups in one of the permanent magnet columns is as follows:

[0007] The polarity of the magnetic pole of the first permanent magnet group is N pole, and the polarity of the magnetic pole of the second permanent magnet group is S pole. Starting from the third permanent magnet group, the polarity of the magnetic pole of the odd-numbered permanent magnet group is the same as that of the previous permanent magnet group, and the polarity of the magnetic pole of the even-numbered permanent magnet group is opposite to that of the previous permanent magnet group.

[0008] A linear motor as described above, the pole pitch L of two adjacent permanent magnet groups in the permanent magnet column is the same, the coil group includes at least one sub-coil with the same specification, the number i of the sub-coils in each coil group is the same, and the center distance P between two adjacent coil groups is the same. The three parameters of the pole pitch L, the number i, and the center distance P satisfy:

[0009] A linear motor as described above, when the coil group includes at least two sub-coils, the center distance Q between two adjacent sub-coils in the coil group is the same.

[0010] A linear motor as described above, the two parameters of the pole pitch L and the center distance Q satisfy: Q = 2L.

[0011] A linear motor as described above, the installation mechanism and the two permanent magnet columns form the mover of the linear motor, and the three coil groups form the stator of the linear motor.

[0012] A linear motor as described above, the installation mechanism includes a bottom plate and two side plates perpendicular to the bottom plate. The two side plates are parallel and opposite to each other, and the two permanent magnet columns are located between the two side plates and are respectively fixedly connected to the two side plates.

[0013] A linear motor as described above, the installation mechanism is an integrally formed integral structure, and the installation mechanism is a magnetic conductive material.

[0014] A linear motor as described above, the installation mechanism is connected with a sliding mechanism for it to slide.

[0015] A linear motor as described above, the sliding mechanism includes a track fixed on the bearing surface, a slider connected to the track and capable of sliding along it, and the installation mechanism is fixedly connected to the slider.

[0016] A linear motor as described above, there are two tracks arranged in parallel, and the installation mechanism can slide along the tracks.

[0017] The beneficial effects of the present invention are:

[0018] 1. Compared with the existing linear motors, when the present invention outputs the same driving force, the present invention uses a smaller number of permanent magnet monomers, thereby greatly reducing the volume of the linear motor, greatly reducing the production cost, and improving the utilization efficiency of the permanent magnet monomers well, with strong practicability.

[0019] 2. Compared with the existing linear motors, under the condition of unchanged output power, the driving force fluctuation range output by the present invention is narrower, and can be maintained at about 0.9%. The driving force output is more stable, and precise control of the output speed can be achieved. Especially in the heavy load or high-speed state, the linear motor of the present invention runs more smoothly and reliably, the output speed control accuracy is higher, the structure is simple, and the practicability is strong. [Description of the Drawings]

[0020] Figure 1 is a schematic structural diagram of one of the permanent magnet column arrangement structures of the present invention;

[0021] Figure 2 is a schematic structural diagram of the second permanent magnet column arrangement structure of the present invention;

[0022] Figure 3 is a schematic structural diagram of one of the coil group structures of the present invention;

[0023] Figure 4 is a schematic structural diagram of the second coil group structure of the present invention;

[0024] Figure 5 is a schematic structural diagram of Embodiment 1 of the present invention;

[0025] Figure 6 is Figure 5 a cross-sectional view in the direction of the arrow at A-A in

[0026] Figure 7 is a schematic structural diagram of Embodiment 2 of the present invention;

[0027] Figure 8 is a schematic structural diagram of one of the permanent magnet column arrangement structures of the existing linear motor;

[0028] Figure 9 is a schematic structural diagram of the second permanent magnet column arrangement structure of the existing linear motor;

[0029] Figure 10 is a schematic structural diagram of the third permanent magnet column arrangement structure of the present invention;

[0030] Figure 11 is Figure 8 、 Figure 9 、 Figure 10 the change trend diagram of the magnetic induction intensity of

[0031] Figure 12 is Figure 5 the driving force fluctuation curve graph of [Detailed Embodiments]

[0032] The following is a more detailed description of the embodiments of the present invention in conjunction with the drawings:

[0033] As shown Figures 1 to 7 in the figure, a linear motor includes an installation mechanism 3. A number of permanent magnet monomers 100 with the same specifications are fixedly connected to the installation mechanism 3. At least one of the permanent magnet monomers 100 is arranged side by side to form a permanent magnet group 10. All the permanent magnet monomers 100 in the permanent magnet group 10 with the same polarity magnetic poles are arranged on the same side to respectively form the N pole and the S pole of the permanent magnet group 10. At least four of the permanent magnet groups 10 are arranged side by side in a straight line to form a permanent magnet row 1. There are two permanent magnet rows 1 and they are distributed in parallel. The magnetic poles at both ends of all the permanent magnet groups 10 in the permanent magnet row 1 are arranged side by side. The number of permanent magnet groups 10 in each permanent magnet row 1 is an even number. There is a gap between the two permanent magnet rows 1 and they are arranged opposite to each other left and right. Three coil groups 5 that can move relative to them are arranged between the two permanent magnet rows 1. The polarities of the opposite magnetic poles between the two permanent magnet rows 1 are opposite. The arrangement rule of the magnetic poles on the same side of all the permanent magnet groups 10 in one of the permanent magnet rows 1 is as follows:

[0034] The polarity of the magnetic pole of the first permanent magnet group 10 is the N pole, and the polarity of the magnetic pole of the second permanent magnet group 10 is the S pole. Starting from the third permanent magnet group 10, the polarity of the magnetic pole of the odd-numbered permanent magnet group 10 is the same as that of the previous permanent magnet group 10, and the polarity of the magnetic pole of the even-numbered permanent magnet group 10 is opposite to that of the previous permanent magnet group 10.

[0035] The permanent magnet monomer 100 is a single magnet, Figure 8 which is one of the permanent magnet arrangement structures of the existing linear motor. In this arrangement structure, two rows of permanent magnets face each other. There are only three permanent magnets in each row of permanent magnets. The arrangement order of the left magnetic poles of the right row of permanent magnets is "N pole - S pole - N pole". The change trend of the magnetic induction intensity of the magnetic field along the permanent magnet arrangement direction at the middle position between the two rows of permanent magnets is as shown by the curve a in Figure 11 . Figure 11 In the coordinate system in , the X-axis represents the middle position between the two rows of permanent magnets, and the Y-axis represents the magnitude of the magnetic induction intensity of the magnetic field. Figure 9 which is the second permanent magnet arrangement structure of the existing linear motor. In this structure, two rows of permanent magnets face each other. There are only six permanent magnets in each row of permanent magnets. The arrangement order of the left magnetic poles of the right row of permanent magnets is "N pole - S pole - N pole - S pole - N pole - S pole". The change trend of the magnetic induction intensity of the magnetic field along the permanent magnet arrangement direction at the middle position between the two rows of permanent magnets is as shown by the curve b in Figure 11 . Figure 10This is the third permanent magnet arrangement structure of the linear motor of the present invention. In this structure, each permanent magnet group 10 includes a single permanent magnet 100. Each permanent magnet row 1 includes six permanent magnet groups 10. The arrangement of the left magnetic poles of all the permanent magnet groups 10 in the rightmost permanent magnet row 1 satisfies the above magnetic pole arrangement rule. The variation trend of the magnetic induction intensity of the magnetic field along the arrangement direction of the single permanent magnets 100 at the middle position between the two permanent magnet rows 1 is as Figure 11 shown by the curve c in

[0036] By Figure 11 comparing the three curves in

[0037] compared with the existing permanent magnet arrangement structure of the linear motor, for the permanent magnet arrangement structure of the linear motor of the present invention, when using the same number of single permanent magnets 100, the magnetic induction intensity of the magnetic field at the middle position between the two permanent magnet rows 1 in the present invention is greater, and the variation trend of the magnetic induction intensity of the magnetic field along the arrangement direction of the single permanent magnets 100 at the middle position between the two permanent magnet rows 1 is closer to a sine curve. The linear motor of the present invention can output a greater driving force during operation; when obtaining the same driving force, the linear motor of the present invention uses a smaller number of single permanent magnets 100, which can greatly reduce the volume of the linear motor, greatly reduce the production cost, and improve the utilization efficiency of the single permanent magnets 100 well, with strong practicability.

[0038] The pole pitch L is the distance between the central positions of two adjacent permanent magnet groups 10 in the permanent magnet row 1. The central position of the permanent magnet group 10 is the geometric center of the permanent magnet group 10. As Figure 1 shown, the permanent magnet group 10 includes a single permanent magnet 100, the permanent magnet row 1 includes eighteen permanent magnet groups 10, and the pole pitch L is the distance between the central positions of two adjacent single permanent magnets 100. As Figure 2 shown, the permanent magnet group 10 includes three single permanent magnets 100, the permanent magnet row 1 includes six permanent magnet groups 10, the central position of the permanent magnet group 10 is the center of the middle single permanent magnet 100, and the pole pitch L is the distance between the central positions of two adjacent permanent magnet groups 10.

[0039] The center pitch P is the distance between the central positions of two adjacent coil groups 5. The central position of the coil group 5 is the geometric center of the coil group 5. As Figure 3As shown, each coil group 5 includes a sub-coil 50, and the center pitch P is the distance between the center positions of two adjacent sub-coils 50. As Figure 4 shown, each coil group 5 includes two sub-coils 50. The center position of the coil group 5 is the midpoint between the center positions of the two sub-coils 50 within the coil group 5, and the center pitch P is the distance between the midpoint positions of two adjacent coil groups 5.

[0040] Figure 12 For Figure 5 is the driving force fluctuation curve of the linear motor of the present invention. When the output power remains unchanged, the driving force fluctuation range of the linear motor of the present invention is narrower, and can be maintained at about 0.9%. The driving force output is more stable, enabling precise control of the output speed. Especially in the state of heavy load or high speed, the linear motor of the present invention runs more smoothly and reliably, has higher output speed control accuracy, a simpler structure, and stronger practicability.

[0041] When the coil group 5 includes at least two sub-coils 50, the center pitch Q between two adjacent sub-coils 50 within the coil group 5 is the same.

[0042] The center pitch Q is the distance between the centers of two adjacent sub-coils 50 within the coil group 5. As Figure 4 and Figure 7 shown, each coil group 5 includes two sub-coils 50, and the center pitch Q is the distance between the center positions of two adjacent sub-coils 50 within the coil group 5.

[0043] The pole pitch L and the center pitch Q satisfy: Q = 2L.

[0044] As Figures 5 to 7 shown, the mounting mechanism 3 and the two permanent magnet arrays 1 constitute the mover of the linear motor, and the three coil groups 5 constitute the stator of the linear motor. Or the mounting mechanism 3 and the two permanent magnet arrays 1 constitute the stator of the linear motor, and the three coil groups 5 constitute the mover of the linear motor.

[0045] The mounting mechanism 3 includes a bottom plate 31 and two side plates 32 perpendicular to the bottom plate 31. The two side plates 32 are parallel and opposite to each other, and the two permanent magnet arrays 1 are located between the two side plates 32 and are respectively fixedly connected to the two side plates 32.

[0046] The mounting mechanism 3 is an integrally formed integral structure, and the mounting mechanism 3 is a magnetic conductive material. The permanent magnet monomer 100 is adsorbed on the mounting mechanism 3, and the mounting mechanism 3 can greatly enhance the magnetism of the permanent magnet monomer 100, with a simpler structure and stronger practicability.

[0047] The installation mechanism 3 is connected to a sliding mechanism 4 for it to slide. When the three coil groups 5 form the mover of a linear motor, the sliding mechanism 4 is movably connected to the coil groups 5 to enable the coil groups 5 to slide.

[0048] The sliding mechanism 4 includes a track 41 fixed on the bearing surface. A slider 42 capable of sliding along the track 41 is connected to the track 41, and the installation mechanism 3 is fixedly connected to the slider 42.

[0049] There are two tracks 41 arranged in parallel, and the installation mechanism 3 can slide along the tracks 41.

[0050] The polarities of the three coil groups 5 are determined by the current directions of the coil groups 5. A linear motor driver can be used to control the current directions and magnitudes of the three coil groups 5, and the current waveform of each sub-coil 50 is a sine wave. In Figure 5 the illustrated embodiment, each coil group 5 includes one sub-coil 50. The three sub-coils 50 are respectively a U-phase sub-coil, a V-phase sub-coil, and a W-phase sub-coil. In order to obtain the maximum output driving force, the current phases of adjacent sub-coils 50 are respectively staggered by 120 degrees. For example, the current phase difference between the U-phase sub-coil and the V-phase sub-coil is 120 degrees, and the current phase difference between the V-phase sub-coil and the W-phase sub-coil is 120 degrees.

[0051] In Figure 7 the illustrated embodiment, the three coil groups 5 are respectively a U-phase coil group, a V-phase coil group, and a W-phase coil group. Each coil group 5 includes four sub-coils 50. That is, the U-phase coil group includes U1 sub-coil, U2 sub-coil, U3 sub-coil, and U4 sub-coil; the V-phase coil group includes V1 sub-coil, V2 sub-coil, V3 sub-coil, and V4 sub-coil; the W-phase coil group includes W1 sub-coil, W2 sub-coil, W3 sub-coil, and W4 sub-coil. In order to obtain the maximum output driving force, the current phases of adjacent sub-coils 50 within each coil group 5 are respectively staggered by 180 degrees. For example, within the U-phase coil group, the current phases of U1 sub-coil and U3 sub-coil are the same, the current phases of U2 sub-coil and U4 sub-coil are the same, and the current phase difference between U1 sub-coil and U2 sub-coil is 180 degrees; the current phases of the sub-coils 50 with the same digital number in adjacent coil groups 5 are respectively staggered by 120 degrees, that is, the current phase difference between U1 sub-coil and V1 sub-coil is 120 degrees, the current phase difference between U2 sub-coil and V2 sub-coil is 120 degrees, the current phase difference between U3 sub-coil and V3 sub-coil is 120 degrees, the current phase difference between U4 sub-coil and V4 sub-coil is 120 degrees, the current phase difference between V1 sub-coil and W1 sub-coil is 120 degrees, the current phase difference between V2 sub-coil and W2 sub-coil is 120 degrees, the current phase difference between V3 sub-coil and W3 sub-coil is 120 degrees, and the current phase difference between V4 sub-coil and W4 sub-coil is 120 degrees.

Claims

1. A linear motor, characterized in that: It includes an installation mechanism (3), and a number of permanent magnet monomers (100) with the same specifications are fixedly connected to the installation mechanism (3). At least one of the permanent magnet monomers (100) is arranged side by side to form a permanent magnet group (10). All the permanent magnet monomers (100) within the permanent magnet group (10) have the same-polarity magnetic poles arranged on the same side to form the N pole and the S pole of the permanent magnet group (10) respectively. At least four of the permanent magnet groups (10) are arranged side by side in a straight line to form a permanent magnet row (1). There are two permanent magnet rows (1) which are distributed in parallel. The number of permanent magnet groups (10) in each permanent magnet row (1) is an even number. There is a gap between the two permanent magnet rows (1) and they are arranged opposite to each other left and right. Three coil groups (5) capable of moving relative to them are provided between the two permanent magnet rows (1). The polarities of the opposite magnetic poles between the two permanent magnet rows (1) are opposite. The arrangement rule of the magnetic poles on the same side of all the permanent magnet groups (10) in one of the permanent magnet rows (1) is as follows: The polarity of the magnetic pole of the first permanent magnet group (10) is N pole, and the polarity of the magnetic pole of the second permanent magnet group (10) is S pole. Starting from the third permanent magnet group (10), the polarity of the magnetic pole of the odd-numbered permanent magnet group (10) is the same as that of the previous permanent magnet group (10), and the polarity of the magnetic pole of the even-numbered permanent magnet group (10) is opposite to that of the previous permanent magnet group (10).

2. The linear motor according to claim 1, wherein: The pole pitch L between two adjacent permanent magnet groups (10) within the permanent magnet column (1) is the same. The coil group (5) includes at least one sub-coil (50) with the same specification. The number i of the sub-coils (50) within each coil group (5) is the same. The center-to-center distance P between two adjacent coil groups (5) is the same. The pole pitch L, the number i, and the center-to-center distance P satisfy:

3. A linear motor according to claim 2, characterized in that: When the coil group (5) includes at least two of the sub-coils (50), the center distance Q between two adjacent sub-coils (50) within the coil group (5) is the same.

4. A linear motor according to claim 3, characterized in that: The pole pitch L and the center distance Q satisfy: Q = 2L.

5. A linear motor according to any one of claims 1-2, characterized in that: The installation mechanism (3) and the two permanent magnet rows (1) constitute the mover of the linear motor, and the three coil groups (5) constitute the stator of the linear motor.

6. The linear motor according to claim 5, characterized in that: The installation mechanism (3) includes a bottom plate (31) and two side plates (32) perpendicular to the bottom plate (31). The two side plates (32) are parallel and opposite to each other. The two permanent magnet rows (1) are located between the two side plates (32) and are respectively fixedly connected to the two side plates (32).

7. A linear motor according to claim 6, characterized in that: The installation mechanism (3) is an integrally formed integral structure, and the installation mechanism (3) is a magnetic conductive material.

8. A linear motor according to claim 5, characterized in that: The installation mechanism (3) is connected with a sliding mechanism (4) for its sliding.

9. The linear motor according to claim 8, wherein: The sliding mechanism (4) includes a track (41) fixed on the bearing surface. A slider (42) capable of sliding along the track (41) is connected to the track (41). The installation mechanism (3) is fixedly connected to the slider (42).

10. A linear motor according to claim 9, characterized in that: There are two tracks (41) which are arranged in parallel, and the installation mechanism (3) can slide along the track (41).

Images