JPS61173606A - Traveling vehicle by linear motor - Google Patents

Abstract

PURPOSE:To efficiently accelerate and start a truck by controlling to energize a stator to start the truck at the position displaced in the reverse direction to the accelerating direction from the position of the stator at the position of the truck when starting the truck. CONSTITUTION:The idly traveling first truck 1 has a reaction plate 3 stood on the lower end of a casing 2 capable of placing a load, and receives a propulsive force or a reverse propulsive force by stators 9 provided at the prescribed interval along a railway 6 to travel A control circuit 1 inputs starting position information and stopping position information from the truck 1 through an operation unit 13, and stops the truck 1 at the position displaced in the reverse direction to the accelerating direction from the position of the stator 9. A drive circuit 10 supplies 2-phase or 3-phase AC from a power source 12 by a control signal of the control circuit 11, for example, through an inverter to the stator 9, thereby switching and regulating the thrust. Accordingly, since the thrust generating zone increases in length at the accelerating time, the thrust is increased.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to an improvement in a method of accelerating the stator or the secondary conductor from a stationary state using a linear motor consisting of a stator and a secondary conductor.

[Technical background of the invention and its problems] An example of this type of device is a traveling device using a linear induction motor. This traveling device is provided with a reaction plate (secondary conductor) as a movable element so as to be able to freely travel along a traveling path, and also has a plurality of stators arranged at a distance along the traveling path as stators, and the vehicle passes through the stators. A magnetic flux that changes over time is applied to the reaction plate, and this change causes the reaction plate to generate a constant propulsive force or reverse propulsive force to move and stop the movable element.

By the way, when accelerating the movable element from a resting state, it has been usual to make the centers of the movable element and the stator coincident with each other in the longitudinal direction along the travel path.

However, in order to accelerate the mover to a predetermined speed, the larger the tm of the moving body equipped with the mover, the greater the propulsive force required, and according to the above method, it is not necessary unless the size of the mover and stator itself is increased. We were unable to obtain the driving force to do so.

[Object of the Invention] The present invention has been made in view of the above circumstances, and it is an object of the present invention to provide a traveling device using a linear motor that can efficiently accelerate and start a mover while maintaining the miniaturization of the linear motor. The purpose is to

[Summary of the Invention] The outline of the present invention for achieving the above object is to provide a running system in which either a stator or a secondary conductor is used as a stator and the other as a movable element, and the movable element is accelerated by energizing the stator. In the device, when the mover is accelerated and started, the center position of the mover in the longitudinal direction along the acceleration direction is shifted from the center position of the stator in the longitudinal direction in a direction opposite to the acceleration direction. The present invention is characterized in that a control means is provided for controlling energization of the stator in order to accelerate and start the movable element at the position where the movable element is moved.

[Embodiment of the Invention] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. This embodiment relates to a traveling system using a linear induction motor.

Fig. 1 is a schematic perspective view of the traveling body and guide rail, Fig. 2 is a vertical cross-sectional view of the running path of the traveling body, and Fig. 3 is a schematic perspective view of the traveling body and the guide rail.
8 is a cross-sectional view showing the cross section, FIG. 4 is an explanatory diagram of the operating principle of the linear induction motor, FIG. 5 is a schematic explanatory diagram of the running path, FIG. 6 is a block diagram of the stator drive control system, and FIG. 7 (A >, (
B) is an explanatory diagram of the operation at the time of acceleration start.

In FIGS. 1 and 2, the inertial traveling body has a reaction plate 3 as a secondary conductor erected at the lower end of a casing 2 on which articles can be loaded. This reaction plate 3 is a metal plate made of copper, aluminum, etc., and is adapted to be provided with propulsive force or reverse propulsive force based on magnetic flux generated from a stator 9, which will be described later. In addition, the running body 1
The leading end side and the rear end side of the vehicle with respect to the traveling direction A are as follows.
A total of four wheels 4, two wheels each serving as guided members, each having a circumferential surface that protrudes beyond the width of the housing 2 are arranged. Further, on both sides of the housing 2 in the traveling direction A of the first traveling body 1, four wheels 5, which are guided members, are arranged on one side, two on each side on the top and bottom, and a total of four wheels 5 on both sides. The running path 6 of the first running body 1 is formed by arranging guide rails (tracks) 7.7 having a trowel-shaped cross section and facing each other with their opening ends facing inward. The distance a between the inner surfaces 7a and 7c of the guide rail 7.7 is slightly better than the length b in the width direction of the first traveling body 1 formed by the wheels 4, 4.

Moreover, the separation distance C formed by the face-shaped facing surfaces 7b and 7c of the guide rail 7 is slightly longer than the distance d from the upper end to the lower end of the wheel 5. In addition, the inner surface 7
a, and the opposing surfaces 7b and 7c are the wheels 4.a and 7c, which are the guided members.
It is a guide surface of 5°. A linear induction motor 8 is provided below the travel path 6. This linear induction motor 8 consists of a reaction plate 3 as a movable element attached to the housing 2, and a pair of stators 9.9 as stators disposed opposite to each other across the running path of the reaction plate 3. ing. As shown in FIGS. 3 and 4(a), the stator 9.9 is made by laminating electric iron plates with teeth and grooves punched out therein, and a coil is wound around the trapezoid. Note that a gap of a certain distance Q is provided between the reaction plate 3 and the stator 9.

Here, the principle of generation of propulsive force or reverse propulsive force by the linear induction motor will be briefly explained with reference to FIGS. 4(a) and 4(b). FIG. 4(a) is a schematic perspective view of a planar one-sided type linear induction motor as an example, and FIG. 4(b) is a characteristic diagram showing the relationship between magnetic flux bO and eddy current jr. When a two-phase or three-phase alternating current is passed through the coil of the stator 9, the instantaneous value of the magnetic flux density at the gap bq (T> is the peak value of B9, and b Q = B g cos (ω is - πχ/τ ) Here, ω-2πf: angular frequency of power supply (rad/s) f double layer wave number (Hz) t: time (s) χ: distance on the stator surface (m) τ: ball pitch (W). The ball pitch τ is the length of a half period of magnetic flux density.Also, since the magnetic flux generated from the stator 9 is alternating current, it generates an eddy current in the reaction plate 3, which is a movable element, according to Lenz's law. Figure 4 (a)
Marks and X shown in the cross section of the reaction plate 3 shown in the figure.
The marks represent the direction in which eddy current flows and its magnitude.

The instantaneous value jr of this eddy current is jr-Jr 5in (ωt-ycz/r-ψ), where ψ is a phase difference based on the impedance of the reaction plate 3. The magnetic flux density bg of the gap is shifted! Since an IJI field is formed, the product of this magnetic flux density bg and eddy current jr generates a continuous thrust F according to Fleming's left hand rule. Note that this thrust is generated in either the left or right direction in Fig. 4(a), but as shown in Fig. 4(b).
Since bgxjr in the left region is larger than that in the right region, the reaction plate 3 moves to the left. Further, in order to apply a reverse propulsion force to the reaction plate 3, an alternating current of opposite phase may be caused to flow through the coils of the stator 9. As a method of varying the magnitude of this propulsive force F, methods such as varying the alternating current frequency f or varying the alternating current amplitude are adopted.

Next, the traveling path 6 of the traveling body 1 to which the propulsion force is applied as described above will be explained with reference to FIG. 5. Driving route 6
As shown in FIG. F is arranged so that propulsive force or reverse propulsive force can be applied to the reaction plate 3 of the traveling body 1 at each position.

Next, a drive control system for each of the stators 9A to 9F will be explained with reference to FIG. 6.

A drive circuit 10 connected to each stator 9 (stators 9A to 9F) drives each stator 9 at a predetermined timing to generate a predetermined propulsive force or reverse propulsive force. The drive circuit 10 is connected to a power supply 12 and a control circuit 11, receives two-phase or three-phase alternating current from the power supply 12, and supplies the stator 9 to one stator 9 selected based on a control signal from the control circuit 11. The drive energy based on alternating current is inputted in a variable manner. The drive circuit 10 and the control circuit 11 constitute a control means 14 for the stator 9. This drive circuit 10 includes a frequency conversion means such as an inverter, and the control circuit 11
The magnitude of the thrust (propulsive force or reverse propulsive force) generated by each stator 9 is varied by varying the alternating current frequency based on a control signal from the stator 9. Furthermore, the drive circuit 10 includes a switching means for switching the input terminals of the stator coils into which two-phase or three-phase alternating current is input, and operates the switching means based on the control signal from the control circuit 11 to It is designed to generate a propulsive force or to input an alternating current of the opposite phase to this to generate a reverse propulsive force. The control circuit 11 controls the drive circuit 10 to control the traveling and stopping of the traveling body 1 based on starting position information and stop position information of the traveling body 1 inputted through the operation unit 13. be. Here, in this control circuit 11, as shown in FIG. 7(A), the center position a2 in the longitudinal direction of the reaction plate 3, which is a movable element, in the acceleration direction is equal to the length of the stator 9, which is a stator. The stator 9 is energized via the drive circuit 10 so that the traveling body 1 is accelerated from a stationary state at a position shifted in the direction opposite to the acceleration direction A from the center position a1 of the direction. .

The operation of the device configured as above will be explained.

As input information to the operation unit 13, the traveling body 1 is connected to the stator 9.
Assume that it is input that the engine should be started from position A and stopped at position 9F of stator. At this time, the control means 14 avoids starting the traveling body 1 by setting the position shown in FIG. There are two possible ways to do this. One is when stopping the traveling body 1 at each stator 9, taking into consideration the direction during the next traveling, as shown in FIG. 7(A), both center positions al, This is a method in which a2 is stopped at a shifted position and accelerated and started from this position.The other method is to set the stopping position of the traveling body 1 at the center of both sides as shown in No. 7 (B). ff1a1.82, or stop the traveling body 1 without considering the stop position, and when accelerating the vehicle 1, run the traveling body 1 from the above-mentioned stopping position in the opposite direction to the acceleration direction. Figure 7 (A
) and then accelerates to start.

In any of the above methods, the time for the reaction plate 3, which is a secondary conductor, to pass through the stator 9 and the area on which the thrust is applied during this time increase, so that a large propulsive force can be received.

Moreover, according to the above method, given Reaxidine plate 3. The size of the stator 9 can be utilized to the maximum for efficient acceleration, and even when the traveling body 1 with a weight is to be accelerated and started, the rear accisine plate 3.
It is possible to accelerate to a predetermined final speed without increasing the size of the stator 9.

It should be noted that the present invention is not limited to the above-mentioned embodiments, and various modifications can be made within the scope of the gist of the present invention. For example, various linear motors such as a linear induction motor can be used as the linear motor.

Further, although the above embodiment uses a double-sided linear motor, a single-sided linear motor can also provide the same effect. In addition, in the embodiment, the running system was constructed using the reaction plate 3 as a secondary conductor as a movable element and the stator 9 as a stator, but conversely, the secondary conductor is used as a stator and the stator as a movable element runs. You may also do so.

[Effects of the Invention] As detailed above, according to the present invention, since the movable element and the stator of the linear motor are shifted from each other, the movable element is accelerated and started. next conductor,
The size of the stator can be utilized to the maximum for efficient acceleration. That is, the acceleration time of the linear motor (the time during which the secondary conductor and the stator act as a motor) can be increased, thereby enabling efficient acceleration.

Therefore, the secondary conductor to obtain a given final velocity.

It is possible to reduce the size and cost of the traveling device without increasing the size of the stator.

[Brief explanation of the drawing]

Fig. 1 is a schematic perspective view of the traveling body and guide rail, Fig. 2 is a vertical cross-sectional view of the running path of the traveling body, and Fig. 3 is a schematic perspective view of the traveling body and the guide rail.
4(a) and 4(b) are explanatory diagrams of the operating principle of the linear induction motor, FIG. 5 is a schematic explanatory diagram of the running path, and FIG. 6 is a block diagram of the drive control system. Figure 7 (A),
(B) is a schematic explanatory diagram for explaining the acceleration start operation. 3... Secondary conductor, 9... Stator, 14... Control means, A... Acceleration direction, al, a2... Center position. Figure 2 Funeral 3 Figure 4

Claims (3)

[Claims] (1) A traveling device that has a linear motor consisting of a stator and a secondary conductor, uses either the stator or the secondary conductor as a stator, the other as a movable element, and accelerates the movable element by energizing the stator. , when the mover is accelerated and started, the center position of the mover in the length direction along the acceleration direction is shifted from the center position of the stator in the length direction in a direction opposite to the acceleration direction. 1. A traveling device using a linear motor, comprising: a control means for controlling energization of a stator in order to accelerate and start the movable element at a certain position. (2) The control means controls energization of the stator in order to cause the movable element to once travel from a stop position in a direction opposite to the acceleration direction, and then to start in the acceleration direction. Traveling device using a linear motor. (3) The control means controls energization of the stator so as to stop the stator and the movable element at a position where their center positions are shifted in the direction, and to start the movable element from this position. A traveling device using a linear motor according to item 1.