KR19980078351A - Linear step motor - Google Patents

Abstract

The linear step motor according to the present invention includes a plurality of iron cores provided with a plurality of protruding poles in which a plurality of teeth having a predetermined pitch are formed at an end thereof, at least one permanent magnet and a plurality of iron cores respectively coupled to the plurality of iron cores. A linear step motor having a mover having coils each wound and a stator having a plurality of teeth having a predetermined pitch formed at a portion facing the mover, wherein the coils are respectively wound around a plurality of protruding poles of the iron core. The plural teeth of a different pitch from the pitch of the stator of the stator are formed at the end portions of the plurality of protruding poles.

According to the present invention, since the pitch arrangement and the combination of the mover and the stator are different from each other, the generating force has an ideal sine wave shape, and as a result, accurate force control is possible and the positional error at the time of stopping can be significantly reduced. have.

Description

Linear step motor

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a linear step motor for use in a precision position control device and the like, and more particularly to a linear step motor structurally improved to improve the positional accuracy of the mover.

In general, a linear motor is a motor in linear motion, the basic principle of which is similar to an induction motor. That is, in an induction motor, a magnetic field is generated in the stator winding by the supply of AC power, and a force in accordance with Fleming's left hand law is generated by the rotating magnetic field and the current flowing in the rotor winding, thereby causing the rotor to rotate. On the contrary, the linear motor uses a moving magnetic field instead of the rotating magnetic field, thereby linearly moving instead of rotating.

The linear step motor is a variation of the linear motor as described above. The stator has a principle of step motor, i.e., a multiphase winding in the stator, and a stator core having a protruding pole slightly shifted from the stator core and the pitch, The application of the principle of moving the mover by sucking the protruding poles of the mover by excitation of the multiphase windings provided in this order is to move linearly at a predetermined distance in response to an electrical pulse.

1 and 2 schematically show a conventional linear step motor, FIG. 1 is a device configuration diagram in which two permanent magnets are used, and FIG. 2 is a device configuration diagram in which one permanent magnet is used. .

First, referring to FIG. 1, the conventional linear step motor is largely composed of a movable element 11 that is a dynamic device element and a stator 12 that is a static device element. The mover 11 is wound around two iron cores 13 and 14 each having two protruding poles 13a, 13b, 14a and 14b, and two iron cores 13 and 14, respectively. It provides a path of magnetic flux generated from the coils 15 and 16, the permanent magnets 17 and 18 provided on the two iron cores 13 and 14, respectively, and the two permanent magnets 17 and 18. At the same time, it consists of a yoke 19 made of a magnetic steel sheet which forms two movable magnets 17 and 18 to form one movable structure. The protruding poles 13a, 13b, 14a and 14b and the stator 12 of the movable iron cores 13 and 14 have teeth 12t and 13t of a predetermined pitch. ) Are formed respectively.

FIG. 2 is another example of the conventional linear step motor, which is almost similar to the overall structure of the motor of FIG. 1, but has one permanent magnet 27 between the movable iron cores 23 and 24, and the permanent magnet ( By connecting the two iron cores 23 and 24 by 27), the yoke 19, which is a separate connecting member as in the motor of FIG. 1, is unnecessary, and the number of permanent magnets is reduced to one. In Fig. 2, reference numeral 22 denotes a stator, 22t denotes a stator, 23t and 24t denotes a movable teeth, and 25 and 26 denote coils.

In the conventional linear step motor having the above configuration, the movable teeth 13t, 14t, 23t provided in the iron cores 13, 14, 23, 24 of the movable elements 11, 21. The arrangement of the stator teeth 12t and 22t provided in the 24t and the stator 12 and 22t, as shown in FIG. 3, is provided in the first iron cores 13 and 23 of the mover. Seven teeth (1 to 7) are formed in the first poles (13a) and the third poles (13b) and (23b), respectively, and all the teeth (13t) (23t) of the first poles (13a) and (23a) are formed. ) Are arranged in the same pitch as the teeth 12t and 22t of the corresponding stator 12 and 22 portions, and all teeth 13t and 23t of the third poles 13b and 23b correspond to each other. The teeth 12t and 22t of the stator 12 and 22 portions are arranged such that the pitch is shifted by 1/2 pitch. In addition, as shown in FIG. 4, seven teeth (1 to 1) are also provided in the second poles 14a and 24a and the fourth poles 14b and 24b provided in the second iron cores 14 and 24 of the mover, respectively. 7 is formed, and all the teeth 14t and 24t of the second poles 14a and 24a have a tooth 12t and 22t of the corresponding stator 12 and 22 part and the pitch is 1/4. All teeth 14t and 24t of the fourth poles 14b and 24b are arranged so as to be pitch shifted, and teeth 12t and 22t of the corresponding stator 12 and 22 portions are 3/4 in pitch. It is arranged so that pitch may shift. Therefore, when current is sequentially applied to each of the coils 15, 16, 25, and 26, magnetic flux is generated by each of the coils 15, 16, 25, and 26. The movers 11 and 21 are moved by the interaction of the magnetic flux by the permanent magnets 17, 18 and 27 with the magnetic flux by the 15, 16, 25 and 26, respectively. At this time, the movable members 11 and 21 are the first poles 13a and 23a → the second poles 14a and 24a → the third poles 13b and 23b and the fourth poles 14b and 24b. The forces are moved in the order of 1/4 pitch.

On the other hand, in a general linear step motor, when the characteristic curve of the force generated by the arrangement of the mover and the stator has an ideal sinusoidal wave shape according to the change of position according to the mover movement, the mover stops. The position error that occurs is almost zero. The fundamental factor influencing this generating force is the tolerances related to the mechanical dimensions of the pitch of the mover and the stator. If the distribution according to the position of the impurity has a sinusoidal shape, the generating force also has a sinusoidal shape.

However, in the conventional linear step motor of Figs. 1 and 2, the pitches of the movers 11, 21 and the stator 12, 22 are equal to each other, so that the teeth of the movers 11, 21 are different. 13t) The distribution of the permission and the generating force according to the positional change of the 14t, 23t, and 24t does not have an ideal sine wave shape, and a quasi-sinusoidal wave shape as shown in FIG. 5. Therefore, when the movers 11 and 21 are stopped, they have a lot of positional errors, and as a result, it is difficult to expect a position accuracy of a certain degree or more.

The present invention has been made in view of the above problems, and provides a linear step motor that can obtain the resistance and generation force having the sinusoidal curve characteristics by increasing the number of winding coils and varying the pitches of the stator and the mover. There is a purpose.

1 is a schematic configuration diagram of a conventional linear step motor.

Figure 2 is a schematic configuration diagram of another conventional linear step motor.

3 is a diagram showing a mutual arrangement structure of teeth of a first iron core of a mover of a conventional linear step motor and a stator thereof;

Fig. 4 is a diagram showing a structure of mutual arrangement of a second iron core of a mover of a conventional linear step motor and a stator thereof;

5 is a characteristic curve diagram of a generation force and a tolerance of a conventional linear step motor.

Figure 6 is a schematic diagram of the configuration of the first mover and the stator of the linear step motor according to the present invention.

7 is a schematic configuration diagram of a second mover and a stator of the linear step motor according to the present invention.

Fig. 8 is a diagram showing a mutual arrangement of teeth of a first iron core of a first mover of a linear step motor according to the present invention and a stator thereof;

9 is a diagram showing a mutual arrangement of teeth of a first iron core of a second mover of a linear step motor according to the present invention and a stator thereof;

10 is a characteristic curve diagram of the generating force and the tolerance of the linear step motor according to the present invention;

Explanation of symbols for the main parts of the drawings

11,21 ... operator 12,22,62 ... stator

12t, 22t, 62t ... teeth 13,23,63,63 '... first iron core

13a, 23a, 63a, 63a '... first pole 13b, 23b, 63b, 63b' ... third pole

13t, 23t ... first iron core 14,24,64,64 '... second iron core

14t, 24t ... 2nd core 14a, 24a, 64a, 64a '... 2nd pole

14b, 24b, 64b, 64b '... 4th pole 15,16,25,26,65a, 65b, 66a, 66b ... coil

17,18,27 Permanent magnet 19

61 ... First Operator 61 '... Second Operator

65a ', 65b', 66a ', 66b' ... coil 61t ₁ ... first mover first pole

61t ₂ ... 1st Mobile _2nd Pole 61t ₃ ... 1st Mobile _3rd Pole 2

61t ₄ ... 1st Mobile _4th Pole 61t ₁ '... 2nd Mobile _1st Pole 2

61t ₂ '... 2nd Mobile 2nd Pole 61t ₃ ' ... 2nd Mobile _3rd Pole 2

61t ₄ '... 2nd mover 4th pole Lee

In order to achieve the above object, the linear step motor according to the present invention includes a plurality of iron cores provided with a plurality of protruding poles in which a plurality of teeth having a predetermined pitch are formed at an end thereof, and at least one permanently coupled to the plurality of iron cores, respectively. A linear step motor comprising a mover having a magnet and a coil wound around the plurality of iron cores, and a stator having a plurality of teeth having a predetermined pitch formed at a portion facing the mover. It is wound around a plurality of protruding poles, and each of the plurality of protruding pole ends has a feature in that a plurality of teeth of different pitches and pitches of different dimensions of the stator are formed.

According to the present invention, since the pitch arrangement and the combination of the mover and the stator are different from each other, the generating force has an ideal sine wave shape, and as a result, accurate force control is possible and the positional error at the time of stopping can be significantly reduced. have.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

6 and 7 are schematic configuration diagrams of a linear step motor according to the present invention.

6 and 7, the linear step motor according to the present invention, unlike the conventional linear step motor, the first and second two movers (61, 61 ') and the two movers (61) It consists of one stator 62 in which the plurality of teeth 62t of a predetermined pitch are formed in the site | part which faces the (61)). The first and second movers 61, 61 'have basically the same device configuration, except that the first and second movers 61, 61' with respect to the teeth 62t of the stator 62. The starting position of the teeth 61t ₁ and 61t ₁ ′ is configured differently. Then, the structure of the first operator 61 will be described in more detail, and the first operator 61 has the same device configuration as that of the first operator 61 for the second operator 61 ′. Will be replaced by

As illustrated in FIG. 6, the first mover 61 has a plurality of teeth (for example, ten teeth) 61t ₁ , 61t ₃ , 61t ₂ , 61t ₄ having a predetermined pitch at an end thereof. Two iron cores 63 and 64 provided with two protruding poles 63a, 63b, 64a and 64b, respectively, and one permanent magnet coupled between the two iron cores 63 and 64. 67 and coils 65a, 65b, 66a, 66b wound around the protruding poles 63a, 63b, 64a, 64b of the two iron cores 63, 64, respectively. Here, in particular, the plurality of teeth 61t ₁ , 61t ₃ , 61t ₂ , 61t ₄ at the ends of each of the protruding poles 63a, 63b, 64a, 64b is a plurality of teeth of the stator 62. It is formed with a pitch of a dimension different from the pitch of 62t, and the teeth 61t ₁ (61t ₁ ′) of the first and second movable members 61, 61 'with respect to the teeth 62t of the stator 62. The starting position of is configured differently. This will be described in more detail with reference to FIGS. 8 and 9.

As shown in FIG. 8, the starting position of the first tooth of the teeth 61t ₁ of the first pole 63a of the first iron core 63 of the first movable member 61 is the teeth of the stator 62. 62t), and the rest of them are sequentially arranged on the basis of this, and the virtual eleventh start position is exactly 1/4 pitch shifted from the start position of the teeth 62t of the stator 62. The pitch dimension of these 61t ₁ of this first electrode 63a is determined. And, the start position of the first tooth among the teeth 61t ₃ of the third pole 63b of the first iron core 63 of the first movable member 61 is the start position of the teeth 62t of the stator 62. It is configured to deviate 1/2 pitch, and the rest of them are sequentially arranged based on this, and the virtual 11th tooth start position is exactly 1/2 pitch +1/4 of the start position of the tooth 62t of the stator 62. the pitch dimension of these (61t ₃₎ a third electrode (63b) is determined so that the pitch can slip out. The teeth 61t ₂ and 61t ₄ of the second pole 64a and the fourth pole 64b of the second iron core 64 of the first mover 61 are formed of the first mover 61. It is formed in the same arrangement structure as the teeth 61t ₁ and 61t ₃ of the 1st pole 63a of the 1st iron core 63, and the 3rd pole 63b, respectively.

In addition, as shown in FIG. 9, the start position of the first tooth among the teeth 61t ₁ ′ of the first pole 63a ′ of the first iron core 63 ′ of the second movable member 61 ′ is the stator. It is configured to deviate 1/4 pitch from the starting position of the teeth 62t of the 62, and based on this, the remaining ones are sequentially arranged, and the virtual 11th starting position of the teeth 62t of the stator 62 is located. The pitch dimension of these 61t ₁ ′ of this first electrode 63a 'is determined so that it can be shifted exactly 1/4 pitch + 1/4 pitch from the starting position. And, the starting position of the first tooth among the teeth 61t ₃ ′ of the third pole 63b ′ of the first iron core 63 ′ of the second movable member 61 ′ is the tooth 62t of the stator 62. It is configured to deviate 3/4 pitch from the start position of the rest, based on this, the rest are arranged sequentially, the virtual 11th start position is exactly 3/4 pitch than the start position of the teeth (62t) of the stator 62 to slip out of +1/4 pitch is the pitch dimension of the "thereof (61t ₃ a third electrode (63b) ') is determined. In addition, the teeth 61t ₂ ′ and 61t ₄ ′ of the second pole 64 a ′ and the fourth pole 64 b ′ of the second iron core 64 ′ of the second mover 61 ′ are second movable. is formed of a chair (61) of the first core (63 'are _{(61t 1') (61t 3} ') and each of the same arrangement of the first electrode (63a') and a third electrode (63b ') of a).

In the linear step motor of the present invention having the above configuration, the generating force and the tolerance have the ideal sinusoidal curve characteristics as shown in FIG. Therefore, the position error value generated when the movable members 61 and 61 'are stopped is significantly reduced.

As described above, the linear step motor according to the present invention has different pitch arrangements and combinations of the mover and the stator so that the generating force has an ideal sine wave shape, and as a result, accurate force control is possible and Positioning errors can be significantly reduced. Therefore, when the linear step motor of the present invention is employed in a system for controlling the linear step motor by a control device, the positional accuracy can be improved, and the smooth thrust is generated, and semiconductor manufacturing, assembly and inspection requiring high precision is required. Suitable for positioning actuators in equipment (eg wire bonders, stepper exposure equipment, IC probe testers, die bonders) as well as surface mounting device (SMD) equipment (eg chip mounters, screen printers, chip-on board machines) Can be used.

Claims (11)

A mover having a plurality of iron cores provided with a plurality of protruding poles having a plurality of teeth having a predetermined pitch formed at an end thereof, at least one permanent magnet respectively coupled to the plurality of iron cores, and a coil wound around the plurality of iron cores; A linear step motor including a stator having a plurality of teeth of a predetermined pitch formed at a portion facing the mover, wherein the mover is provided with two coils, and the plurality of protruding poles of the iron cores of the two movers are coiled. A plurality of teeth each of which is wound, and a plurality of teeth of a pitch having a different dimension from a plurality of teeth pitches of the stator are formed at the end portions of the plurality of protruding poles. 2. The linear step motor according to claim 1, wherein the first position of the first pole of the first pole of the first iron core of the first mover of the two movers is made to coincide with the start position of the stator. The method according to claim 1 or 2, wherein when the teeth of the first pole of the first iron core of the first mover are ten teeth, the starting position of the virtual eleventh teeth is shifted 1/4 pitch from the starting position of the teeth of the stator. 10. A linear step motor, wherein ten of the first poles of the first iron core of the first mover are arranged. 2. The start position of the first teeth of the third pole of the first iron core of the first mover of the two movers is deviated from the start position of the teeth of the stator by 1/2 pitch. Linear step motor. The start position of the virtual eleventh tooth is 1/2 pitch + 1 / of the stator's tooth position according to claim 1 or 4, when the teeth of the third pole of the first iron core of the first mover are ten teeth. 10. The linear step motor, wherein ten of the third poles of the first iron core of the first mover are arranged so as to deviate by four pitches. The first and third poles of the first and second poles of the first iron core of the first mover, respectively, of the two movers. A linear step motor, characterized in that formed in a structure. The start position of the first tooth of the first pole of the first iron core of the second mover among the two movable members is shifted by a quarter pitch from the start position of the teeth of the stator. Linear step motor. 8. The start position of the virtual eleventh tooth is 1/4 pitch + 1 / of the stator's tooth start position according to claim 1 or 7, wherein the number of teeth of the first pole of the first iron core of the second mover is ten teeth. 10. The linear step motor, wherein ten of the first poles of the first iron core of the second mover are arranged so as to deviate by four pitches. 2. The start position of the first teeth of the third pole of the first iron core of the second mover of the two movers is deviated by 3/4 pitch from the start position of the teeth of the stator. Linear step motor. 2. The start position of the virtual eleventh tooth is 3/4 pitch + 1 than the start position of the stator when the third pole of the first iron core of the second mover among the two movers is 10 teeth. 10. These linear step motors are arranged so that ten of the third poles of the first iron core of the second mover are arranged so as to deviate from each other by 4/4 pitch. The second and fourth poles of the second iron core of the second mover among the two movers, which are the same as the first poles and the third poles of the first iron core of the second mover, respectively. A linear step motor, characterized in that formed in a structure.