JPS6166577A - Stop control method of moving object using induction linear motor - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Application The present invention relates to a method for controlling the stop of a moving body in a conveyance system using a linear motor.

(Although conventional linear motor-driven conveyance devices are generally easy to start and accelerate, a number of considerations are required in control in order to ensure a precise stopping position.)

Conventionally, the method of stopping a linear motor-driven conveyance device is as follows:
Normally, a grooved plate is attached to a moving body and the speed and position are detected and controlled using a pulse counter type sensor, etc., but in order to achieve a high-accumulation stop, a mechanical positioning stop device is also used. Alternatively, a method is known in which the linear motor is made into a special structure in advance and equipped with a single-phase excitation winding for positioning the propulsion winding. However, all of these require complicated special configurations, and a simple and reliable method is desired.

(c) Purpose The present invention adds not only propulsive force to the linear motor itself but also braking force that can constantly stop a moving body at a fixed position with good accumulation,
It is an object of the present invention to provide a method for controlling the stop of a moving body using a dedicated linear motor, which does not require a separate stop mechanism and can simplify the control configuration of the entire system.

(d) Configuration The present invention provides a stop control method for a device that generally transports a moving body to a destination by a linear motor, in which a set of stators is disposed at the destination on the conveyance route, and the stator core is connected to the stator core. To stop a moving body at a fixed position by exciting mutually independent three-phase windings of the same style so that the magnetic fields travel in either one direction, either toward the center of the core or toward both ends of the core. This is a method for controlling the stop of a moving body using an induction linear motor, which is characterized by:

In induction type linear motors, edge effects exist because they are composed of magnetic circuits of finite length, but the present invention eliminates the effects of edge effects on the center side of the iron core when excitation of the three-phase windings. By limiting the length of the reaction plate to a range where the end effects of both end portions of the iron core do not affect the length, the moving body can be stably stopped at a fixed position.

By clarifying the above relationship, the present invention realizes a method of controlling eight moving bodies at a fixed position using a barrel-shaped motor.

(e) Examples Hereinafter, specific examples of the present invention will be described.

FIG. 1 is an explanatory diagram of a method for stopping a moving body using a linear motor according to the present invention. In the figure, A is a moving body, a reaction plate LfJ is disposed below the moving body A, and B is a stator. A near-motor is configured with a relatively opposite direction. Let C be the destination where the moving body A should stop.

FIG. 2 shows three phases on the stator B side of a linear motor according to the present invention, in which the number of slots in the core portion of stator B is 15, the number of windings is 12, and the number of three-phase winding groups is 2. It is a block diagram of a winding. @ u l , vl , W+ and L12 , vfi where the number of three-phase winding groups is the first group and the nth group, respectively
, W2 each represent a terminal. Each terminal u,, u2 has a U
phase to each terminal V, , V, and ■ phase to each terminal w, ,
A W-phase three-phase voltage is applied to w. C11-C16,
C21 to C26 indicate each winding.

Figure 3 is a waveform diagram of the three-phase voltage to be applied, T, ~T7
indicates each time when a predetermined l cycle is divided into six equal parts.

Hereinafter, a specific example will be described in which excitation is applied in the direction in which the magnetic fields advance toward the center of the iron core.

FIG. 4 is a vector diagram showing the phase relationship of the two-phase voltages applied to the three-phase winding group of this embodiment. FIG. 4(A) shows the phase relationship of the three-phase voltages applied to the first group of Sanwa windings, and FIG. 4(B) shows the phase relationship of the three-phase voltages applied to the nth group of three-phase windings.

FIG. 5(A) shows each winding CIl to C16 shown in FIG.
It is a figure which shows the cross-sectional shape of C21-C26 accommodated in each slot of the iron core part of 1 set of stator B. The numbers 31 to S15 in FIG. 5(A) indicate the positions of the slots in the iron core of the stator B. Symbols t1 to 6 indicate the positions of the teeth of the iron core of the stator B. In order to make it easier to understand, FIG. 2 shows which slot of the iron core of which stator B each S wire is housed in, and the positions of the slots of the iron core shown in FIG. Indicated using reference marks.

Figure 5 (B) shows the power supply 1 when the above three-phase voltage is applied.
This is a diagram showing the state of the magnetic field obtained by combining the state of the magnetic field generated by the first group of windings and the nth group of windings for each winding group for three phases according to the time transition of the cycle T, ~T6. be. The a line segment indicates the state of the magnetic field of the first group of windings, and the b line segment indicates the state of the magnetic field of the nth group of windings.

FIG. 6 further shows the magnetic field generated by the first group of windings and the nth group of windings shown in FIG. 5(B).
FIG. 3 is a diagram showing a state of a magnetic field obtained by combining windings of a group.

Hereinafter, the action of the reaction plate and the moving magnetic field according to the present invention will be explained.

The windings of the first group and the nth group shown in FIG.
As shown in the figure, the first
When three-phase voltages having the phase relationships shown in FIG. 4 (A) and (B) are applied to the group and the n-th group, respectively, the first group and the first group at each time T1 to T6 shown in FIG. The state of the magnetic field for each winding group generated by the windings is as shown in the a line and b line shown in FIG. The state of the magnetic field obtained by further combining the two is shown in FIG. However, (1) to (6) in FIG. 5(B) and FIG. 6(B) are waveform diagrams corresponding to times T and -T6. As is clear from FIG. 6, the state of the magnetic field obtained by further combining the magnetic fields transmitted by the windings of the first group and the first group is the same as the power cycle in the range of teeth t5 and t13 of the iron core of stator B. It is a balanced alternating magnetic field with a frequency of 100%, and the end effect at the center of the core has been eliminated.

However, in both end portions of the core other than the above range, that is, between the tooth portions L1 and t5 and between the tooth portions t13 to t16, the end effect is not eliminated and exists. Therefore, in this embodiment, the moving object A
If the length of the reaction plate L is within the length corresponding to the range of teeth t5 and t13 of the iron core of stator B, a stopping braking force will be generated to the center of the iron core, so the purpose of stopping moving body A is Earth cI! In this embodiment, the iron core can always be stably kept at a constant position centered on the peak L9 (2).

In the above, the three-phase voltage shown in Fig. 4 is applied to the Sanwa winding group,
We have explained the case where the magnetic fields are excited in the direction toward the center of the core.Next, we apply three-phase voltage to the Sanwa winding group, and the direction of the magnetic fields is directed toward both ends of the core. A specific example of applying excitation will be explained.

FIG. 7(A) shows the three-phase voltage applied to the first group of Sanwa windings in this embodiment, and FIG. 7(B) shows the phase relationship of the three-phase voltages applied to the three-phase winding groups. It is a hector diagram. Figure 8 is (A
) are each winding C11 to C16, C21 to C2 shown in FIG.
6 is a diagram showing the cross-sectional shape accommodated in each slot of the iron core part of stator B, and FIG. FIG. 4 is a diagram showing a state of a magnetic field obtained by combining the state of the magnetic field generated by the first group of windings and the first group of windings for each winding group for three phases. However, (1) to (6) in FIG. 8(B) are waveform diagrams corresponding to times T1 to T6.

The a line segment shows the state of the magnetic field of the first group of windings, and the b line segment shows the state of the magnetic field of the first group of windings.

FIG. 9 shows the first group of windings shown in FIG. 8(B) and the magnetic field of each winding generated by the first group of windings.
FIG. 3 is a diagram showing a state of a magnetic field obtained by combining windings of a group.

As is clear from FIG. 9, the state of the magnetic field obtained by combining the magnetic fields generated by the first group and the windings of the first group as described in the above embodiment is as follows: A balanced alternating magnetic field having the same frequency as the power supply cycle exists within the range between tooth portions t5 and t13 centered on , and the end effect at the center of the iron core has been eliminated. However, in Figure 9 (B) (
1) to (6) are waveform diagrams corresponding to time TI-T6.However, both ends of the iron core excluding the above range, that is, tooth portion t1
The end effect is not excluded and exists between the teeth L5 and the teeth L5 and between the teeth t13 and t16. Therefore, in this embodiment, as in the previous embodiment, if the length of the reaction plate L of the movable body A is within the length corresponding to the range of teeth t5 and t13 of the iron core of the stator B, the Therefore, the movable body A can be stopped in a very stable position at the destination C, that is, in this embodiment, at a position centered on the teeth t9 of the iron core.

As explained in the above embodiment, when the number of slots in the iron core of one set of stator B is 15, the number of windings is 12, and the number of three-phase winding groups is 2, the direction of magnetic field propagation in each winding is set relative to the iron core. By energizing in one direction, either towards the center or towards both ends of the core, the end effect at the center of the core is eliminated, resulting in a set of balanced alternating magnetic fields. However, between the toothed parts t1 and t5 at both ends of the iron core and between [13 and [
Since the end effect exists without being excluded between 16 and 16, the length of the range corresponding to this part is omitted, that is, in the above embodiment, it corresponds to the range of teeth t5 and t13 of the iron core of stator B. If the reactor plate L has a length within the length of
The stator B can always be stably stopped at a constant position centered on the toothed portion t9 of the iron core.

In the above embodiment, the stator core has 15 slots, 12 windings, and 2 three-phase winding groups, but the present invention is not limited thereto. Therefore,
Select the number of slots and number of windings in the stator core as appropriate.
By applying opposing moving magnetic fields, it is possible to arbitrarily obtain a balanced alternating magnetic field range excluding both ends of the stator core. It becomes possible to arbitrarily select a destination, generate stopping braking force to the central part of the iron core, and realize that the moving object is always stopped stably at a fixed position.

As is clear from the above embodiments, generally all the slots in the stator core are the center of the destination to be stopped and the center of the reaction plate, and the reaction plate is the length of both ends of the core, that is, the slot pitch length. (Ns
-7) By creating the size within twice as much, it is possible to stop the moving body at a fixed position with high precision.

(F) Effects According to the present invention, the following effects are obtained as explained in the above embodiments.

(1) Eliminate end effects and generate stopping braking force by electromagnetic method using a reaction plate of a moving body and a stator having a set of iron cores and windings without adding any special equipment. Since the movable body can be accurately stopped at a stable and constant position, the control configuration of the entire system can be simplified.

(2) By appropriately selecting the number of slots and the number of windings in the iron core of the stator, it is possible to arbitrarily select the length of the reaction plate of the moving body and the position of the destination to which it should stop.

(3) In the case where the reaction plate of the moving object does not use magnetic material and is lightweight, for example, made only of aluminum, and a linear motor is used to move the moving object through air levitation or magnetic levitation. Since no attraction force is generated electromagnetically, this method is extremely effective in obtaining stopping braking force without contact.

(4) R Since the stopping braking force is obtained electromagnetically rather than mechanically, there is less shock when the moving body stops.

[Brief explanation of the drawing]

Fig. 1 is an explanatory diagram of a method for stopping a moving body using a linear motor according to the present invention, and Fig. 2 shows the number of slots in the iron core of the stator: 1
5. A configuration diagram of a three-phase winding of a stator in an example in which the number of windings is 12 and the number of three-phase winding groups is two. Fig. 4 is a vector diagram showing the phase relationship of the three-phase voltages applied to the three-phase winding group when the magnetic fields are excited in the direction toward the center of the iron core. , Fig. 5 is a diagram showing the cross-sectional shape of each winding housed in each slot of the stator core and the state of the magnetic field generated by the first group and nth group windings, and Fig. 6 is a diagram showing the state of the magnetic field generated by the first group and nth group windings. A diagram showing the state of the magnetic field obtained by further combining the magnetic fields generated by the windings of each group. Figure 7 shows the three-phase diagram applied to the three-phase winding group when excitation is applied in the direction in which the magnetic fields advance toward both ends of the iron core. Figure 8 is a vector diagram showing the phase relationship of voltages, and Figure 9 is a diagram showing the cross-sectional shape of each winding housed in the slot of the stator core and the state of the magnetic field generated by the first group and nth group windings. 2 is a diagram showing a state of a magnetic field obtained by further combining the magnetic fields generated by the respective windings of the first group and the n-th group. A... Moving object, B... Stator, C... Destination to stop, and... Reaction plate L<-to, S1 to 51
5...Slot number of stator core, B~6th...
Number of teeth of stator core, CIl~C16, C21-C
26... Winding wire. Patent applicant Hitachi Kiden Kogyo Co., Ltd. Agent
Patent Attorney Takaharu Onishi Fig. 1 C Fig. 2 Fig. 3 Fig. 4 (A) (B) (A) Ul Fig. 7 Handiwork λ1ii Sei 7; (self-motivated) 1980/10/4/3, ldi Person who corrects 6, number of inventions increased by drawing 07, 1 city correct'll figure ill light ♀■ 1', & r detailed explanation of invention j no 8,
Contents of amendment (1) Ming! [[In the ♀ stop control method of a device that generally feeds lines 5 to 7 on page 3 of l book box to The near motor stator is installed on the general feed path, and the three-phase winding is corrected to ``.'' (2) The 9th line of page 9 of the specification is energized to J in either direction toward the r end. (3) Lines 14 to 20 of Book II: ``As is clear from the above example, generally speaking, when the total number of slots and throats in the iron core of the stator is Ns, the 4N5+3)th tooth section The center of the center of the core is the center of the destination to be stopped and the center of the reaction plate, and the reaction plate is the length of the central part of the core excluding the part where the end effect cannot be excluded at both ends of the core, that is, the slot pitch length (Ns -7) By creating within 2 times, it is possible to stop a moving object at a fixed position.'' Procedural amendment (voluntary) August 7, 1985 Director General of the Patent Office, Michibe Uga1, Indication of the case, Patent Application No. 188300 of 19882
, Name of the invention Method for controlling the stop of a moving object using an induction linear motor 3.
Relationship with the case of the person making the amendment Patent applicant Address: 3-11-1 Shimosakabe, Amagasaki City Name: Hitachi Kiden Kogyo Co., Ltd. Representative: Yoshinobu Imamura 4, Agent 6, ? The number of inventions increases due to lli positive 17,
Subject of amendment: Full text of the specification. 8. Contents of amendment The specification will be amended as shown in the attached sheet. Specification 1, Name of the Invention Method for controlling the stop of a moving body using an induction linear motor 2, Claim (1) N! It is equipped with an iron core having a circular slot and two groups of mutually independent three-phase windings wound within the slot, and the amplitude of the magnetic field is varied by applying a symmetrical polyphase alternating voltage to each 1+ wire. are symmetrical about the center of the iron core and are excited in directions in which the traveling directions of the magnetic fields face each other, and the length of the acnosine plate is set within (N-7) times the slot pitch. A method for controlling the stop of a moving object using an induction linear motor. (2) One stop; tI+I control method of a moving body using an induction type linear motor of the first category described in Patent No. 51, characterized in that the symmetrical polyphase alternating voltage is a three-phase alternating voltage. (3) It is equipped with an iron core that accommodates N slots and throats, and two groups of three-phase wires that are independent of each other and are wound inside the slots. By applying an alternating voltage, the amplitude of the magnetic field is excited in a direction that is symmetrical with respect to the center of the core and the traveling direction of the magnetic field is directed toward both ends, and the length of the reaction plate is set within (N-7) times the slot pinch. (4) A method for controlling the stop of a moving object using an induction linear motor, characterized in that the symmetric multiphase alternating voltage is a three-phase alternating voltage. A method for controlling the stoppage of a moving body using an induction linear motor according to item 3. 3. Detailed explanation of the invention Main businessPurification ■And fullness The present invention relates to a method for controlling the stoppage of a moving body using a 3.44 type linear motor.Difference A moving object driven by a linear motor is generally easy to start and accelerate, but it is not so easy to accurately stop the moving object at its destination. As a control method, the moving body is provided with tooth-shaped plates arranged in the direction of movement of the moving body to pass or block light incident in the perpendicular horn direction. The speed and position of the moving object can be determined by providing a light source that makes light incident on the plate and a detector that detects the light that has passed through the plate, and (iii) providing a counter that counts the recorded ratio detector force. A method is used in which the moving object is stopped when it reaches a desired position. However, in the above method, the 1♀ stop ellipse is not very good, so it is necessary to stop the moving object with high precision. In order to achieve this, mechanical means are required in addition to the above methods. However, such methods are inevitably complicated and require special structures, so There is a need for a simple and reliable method.The present invention is capable of stopping a moving object by adding braking force to the linear motor itself, which can accurately stop a moving object at a fixed position, in addition to the propulsive force. The purpose of the present invention is to provide a method for controlling the stop of a moving body using an induction linear motor, which does not require a separate mechanism for controlling the system and can simplify the structure for controlling the entire system. One of these is a device that transports a moving object to a destination using a linear motor. It is wrapped with three-phase winding. The above-mentioned three-phase windings (the windings are arranged so that the directions of the magnetic fields generated by the three-phase windings are in directions facing each other or in opposite directions. Another method is to adjust the length of the reaction plate. In other words, because induction linear motors generally include a magnetic circuit with a finite length due to their structure, there is a magnetic end effect near the end of the magnetic circuit, but this In the invention, the length of the beam plate is limited so as not to be influenced by the magnetic end effect.At the center of the countersunk core, the directions of the magnetic fields based on the three-phase voltages face each other. Therefore, the moving object can be stably stopped at that position. In Figure 1, A is the moving object, and a reaction plate L is provided under the moving object A at the mouth. B is a stator. That is, the rear coupling plate and the stator face each other with a predetermined gap, and the two constitute a linear motor. C shown in the figure is a moving body A. 5t-515 shown in Fig. 2 are 15 slots carved into the stator core in a direction perpendicular to the moving direction of the moving object, and these slots have the How to do <C11
~C16, one winding of C21-C26 is wound,
These windings constitute a first group of three-phase windings and a second group of three-phase windings. Therefore, the three-phase line fli+ has the vector three-phase voltages U1, vl, ■ and 112 as shown in FIG.
, ν2, -2 are applied. T1 to T7 in FIG. 3 represent times when one cycle is divided into six equal parts. Hereinafter, the action between the reaction plate and the magnetic field in the induction linear motor according to the present invention will be explained. Figure 5 (A) shows the windings of the first and second groups shown in Figure 2.
As shown in Figure 4 (A) and Figure 4 (B
), when applying three-phase voltages having the phase relationship shown in Figure 3, the state of the magnetic field at each time T1 to T6 is the fifth
The result will be as shown in a and b shown in Figure (B). The combined magnetic field of a and b is shown in FIG. As can be seen from Fig. 6, this composite magnetic field is a symmetrical alternating magnetic field in the range of teeth L5 and Li3 of the iron core of stator B, proceeding toward tooth L9, and therefore there is a magnetic end effect in the iron core. would have been excluded. However, the part excluding the above range, between the teeth LL and t5, which is the 511th minute of the edge of the J straw iron 7, and between the teeth L13 and 11.
6, the magnetic end effect remains without being eliminated. Therefore, if the length of the reaction plate L to the moving object is within the length corresponding to the range of C L5 and Li2 of the iron core of the stator B, such a moving object will have a stop at the center of the iron core. Since a mechanical force is generated, the movable body can always be stably stopped at the destination C, which is the position of the tooth t9 in this embodiment. The above description is for the case where the three-phase voltage shown in FIG. 4 is applied to the three-phase winding group, and the directions of the magnetic fields are made to face each other toward the center of the iron core. Next, a case will be described in which the directions of the magnetic fields are mutually directed toward both end portions of the iron core. In this case, the three-phase voltages of the vectors shown in FIG.
2.Mari is applied. Figure 8 (A) shows the ridges of the first group and #2 shown in Figure 2.
As shown in Fig. 7(A) and Fig. 7(B), insert the core into the slot of stator B, and insert it into the windings of the first group and the second group, respectively.
When applying three-phase voltages with the phase relationship shown in
The state of the magnetic field at each time T1 to T6 shown in the figure is as shown in a and b shown in FIG. 8(B). The combined magnetic field of a and b is shown in FIG. As is clear from Fig. 9, this composite magnetic field is a symmetrical alternating magnetic field in the range between tooth t9 and Li2 of the iron core of stator B, proceeding from tooth t9 toward both ends. This means that the edge effect has been eliminated. However, the parts excluding the above range, that is, the end part of the iron core between teeth B and L5 and between teeth t13 and Li2
In between, magnetic edge effects remain without being eliminated. However, as in the above embodiment, the length of the reaction plate L of the movable body A is the same as the tooth t5 of the iron core of the stator B and (1
If the length is within the range corresponding to 3, a stopping braking force will be generated on the central part of the iron core in such a moving body, so
The movable body can always be stably stopped at the destination C, in this embodiment at the position of the tooth L9. The above description is based on the case where the three-phase voltage shown in FIG. 7 is applied to the three-phase winding group, and the magnetic fields are directed from the center of the core to both ends. Further, the present invention is not limited to the number of slots and I to the number of lines and the number of phases shown in the above embodiments. The 31st voltage can be referred to as a polyphase alternating voltage. That is, it can be said that selecting these appropriately falls within the scope of the present invention. In more general terms, if the number of slots in the stator core is N, the destination is the mountain at the (N + 3 >i'Zfi mouth) and within (N-7) times the slot pitch. The important point of the present invention is to set a 1m without the need for any special equipment, the traveling direction of the magnetic field is directed toward the center of the stator core at the destination, and the The rear axle lamp plate, either because it is oriented toward the other side and symmetrically, and in addition, because the length of the rear axle lamp plate is limited to the above-mentioned length,
In other words, it is possible to stably stop the moving object at the center of the stator core at the destination. 4. Brief explanation of the drawings Figure 1 shows a stop 1i of a moving body using the linear motor of the present invention.
11 is a principle drawing of the method. Figure 2 shows two three-phase obscuring wires 01 and Vl on stator B in Figure 1.
, 11 and C2, C2 indicate the state in which the lie is wound. FIG. 3 shows the waveforms of the three-phase voltages applied to the three-phase shadow lines. Figure 4 shows the three-phase voltage a applied to the two three-phase single windings.
t, vt, wx and C2, C2, 綽2 are vector diagrams showing the phase relationships, and FIG. The three-phase voltages applied to the second group of three #■ winding wires are respectively shown.
It is a drawing showing a cross section where C21-C26 is housed in the slot of the iron core of stator B. Figure 5 (B) shows the state of the magnetic field generated by the first winding of the first group and the upper line of the second group when the two-phase voltage shown in Figures 4 (A) and (B) is applied. This drawing corresponds to the time course T1 to T6 of the cycle, and the temperature is not shown in °C. Figure WA6 is the WJW when the two magnetic fields are combined by the winding of the first group and the upper line of the second group in Figure 5.
It is J. FIG. 7 shows the three-phase voltages u1, ν! applied to the three-phase obscured wires.
, -1 and C2, C2, -2, and FIG. 7 (^) is the three-phase voltage applied to the first group of three-phase one line, w471! I(B) indicates the three-phase voltages applied to the second group of three-phase stirrers. FIG. 8(^) shows each winding Ctt to C16 shown in FIG.
It is a drawing showing a cross section where C21-C2G is housed in the stator core of the stator B. 811 (B) shows the state of the magnetic field generated by the occult line of the 1st IG and the twist of the 2nd In when the three-phase voltage shown in Fig. 7(A) and (B) is applied in one cycle. It is a drawing shown corresponding to the temporal transition Tl-76. Figure 19 shows the upper line of the first group in Figure 8 and the upper line of the second group.
This is a drawing in which two magnetic fields generated by windings are combined. ^...Moving object, B...Stator, C...Destination, C
Il~C16, C21~C26...t is a line, 31~S
15... Throft.

Claims (1)

[Claims] (1) In a three-phase induction linear motor, two groups of mutually independent three-phase windings of the same style are provided in a set of iron cores having Ns slots, and the respective windings are aligned in the direction of magnetic field propagation with respect to each other. Excite in one direction, either toward the center of the core or toward both ends of the core, and adjust the length of the reaction plate to the slot pitch (Ns-
7) A method for controlling the stop of a movable body using an induction linear motor, which is characterized in that the movable body is stopped at a fixed position by making the movable body at a fixed position.