JPS62114402A - Linear motor type conveyor - Google Patents

Abstract

PURPOSE:To decrease the number of cables wired from a controller by controlling the feed of a primary coil on the basis of the result of detection of a secondary-conductor detecting circuit detecting the position of a secondary conductor according to the value of feeder currents to the primary coil. CONSTITUTION:When a truck is made to travel in the right direction from a station ST, a controller 14 supplies a primary coil 11 with power while supplying the nearest primary coil, a primary coil 1a, in primary coils positioned on the right side of the station ST with power on the basis of an output signal from a sensor 12. A current detecting circuit 15 detects a reaching to the position of the primary coil 1a of a secondary conductor 2 by the change of feeder currents, and transmits a detecting signal over the controller 14. Accordingly, the controller 14 stops feed to the primary coil 11, and starts feed to a primary coil 1b.

Description

DETAILED DESCRIPTION OF THE INVENTION "Field of Industrial Application" The present invention relates to a linear motor type conveyance device that travels along a predetermined conveyance track to convey articles and the like.

``Prior Art'' A linear motor type conveyance device has been developed and has been highly effective, in which a truck or the like supported on a predetermined track so as to be freely movable is driven by the principle of a linear induction motor.

FIG. 3 does not show an example of the configuration of this type of conventional linear motor conveyance device.
1 b and lc are primary coils provided on the ground side, and 2 is a secondary conductor provided on the bogie side.

Iron pieces 3a are provided at the front and rear ends of the secondary conductor 2, respectively.

3b is provided, and the primary coil Ia,
lb.

The iron pieces 3a are located near each front and rear of Ic.

Sensors 4a, 4b, 5a, 5b for detecting 3b
, 6a.

6b is provided. Next, 7 is the sensor 4a, 4b.

This is a control device that controls power supply to primary coils 1a, 1b, and 1c based on output signals of 5a, 5b, Ga, and 6b.

The operation of the conventional linear motor conveyance device with the above configuration is as follows.
An example in which the truck travels in the direction of the arrow in the drawing will be explained.

First, the sensor 4b detects the iron piece 3a, and this detection signal is supplied to the control device 7. As a result, the control device 7
Power is supplied to the secondary coil la to give thrust to the secondary conductor 2. Then, when the secondary conductor 2 passes over the primary coil la, the sensor 4a detects the iron piece 3b, and as a result, the control device 7! The power supply to the next coil la is stopped. After passing through the primary coil Ia, the secondary conductor 2 travels to the right in the drawing due to inertia and enters above the primary coil tb. Then, the control device 7 performs the following operations between the time when the sensor 5b detects the iron piece 3a and the time when the sensor 5a detects the iron piece 3b.
The primary coil Ib is energized to apply thrust to the secondary conductor 2. The control device 7 thereafter performs similar control and supplies power only to the primary coil located above the secondary conductor.

In this way, in the conventional linear motor conveyance device,
A sensor placed in parallel with the primary coil detects the entry of the secondary conductor (Zunaitsuchi trolley), and the primary coil is energized only while the entry is detected.

"Problems to be Solved by the Invention" By the way, in the conventional device described above, it is necessary to provide separate cables for the sensor and for power supply, so the number of cables wired from the control device is extremely large. It had the disadvantage of becoming In particular, it takes a lot of space to store cables near control equipment.
Furthermore, when the track is long, a problem arises in that a large number of cables must be installed over long distances.

The present invention has been made in view of the above-mentioned circumstances, and an object of the present invention is to provide a linear motor transport device in which the number of cables wired from a control device can be extremely reduced.

``Means for Solving the Problems J'' This invention was made in order to solve the above problems, and therefore includes a plurality of primary coils provided along a track, and a bogie provided movably along the track. and a secondary conductor attached to the trolley, and in a linear motor type conveyance device that controls the power supply to each of the primary coils and applies thrust to the secondary conductor, the power supply current to each of the primary coils is controlled. A secondary conductor detection circuit detects whether or not the secondary conductor is located above each of the primary coils by detecting the value of . A sequence control unit that supplies power to the primary coil where it is detected that the secondary conductor is located, and sequentially switches the power supply to the primary coils located before and after the secondary conductor according to the running direction. Equipped with

"Function" When the secondary conductor is placed on the primary coil, the primary coil becomes loaded and its feeding current changes, and this change
Detected by the next conductor detection circuit.

``Example'' Hereinafter, an example of the present invention will be described with reference to the drawings.8 Figure 1 is a schematic diagram of an embodiment of the present invention without showing its configuration, and Figure 3, which is described in detail, The same reference numerals are given to the corresponding parts.

In Fig. 1, +1 is the primary coil installed at station ST, and 12 is the trolley or station ST.
This is a sensor that detects whether the vehicle is located at In this case, a station is a place where various tasks are performed,
For example, it is a place where a mold is loaded and unloaded. The cart is then moved from station to station, and its movement is controlled so that predetermined processes are performed in sequence. Next, 14 is a primary coil 1a, 1b, based on the output signal of the sensor 12 and the current detection circuit 15.
This is a control device that controls power supply to Ic and 11. Further, the current detection circuit 15 includes a primary coil Ia.

The current value supplied to 1b, Ic is detected, and from the change in the detected current value, each primary coil 1a, 1b, I
This circuit detects whether the secondary conductor 2 is located above c. The detection principle in this case is that if the secondary conductor 2 is located above the primary coil, the primary coil will bear the load;
This method takes advantage of the fact that if the secondary conductor is not located, the primary coil will be in an unloaded state, so the current consumption values will be different.

Moreover, FIG. 2 is a sectional view showing a more detailed relationship between the bogie and the track in this embodiment. In this drawing, 2
0 is a cart with a U-shaped cross section, and a secondary conductor 2 is installed on the lower surface of the upper part.
exists. Further, 25 is a track having a hexagonal cross section, and the bogie 20 has four rollers 21 and 2 on both sides of the track 25.
1, 21. It is designed to run while holding the car at 21.

Next, the operation of this embodiment with the above configuration will be explained.

As an example, a case will be described in which a cart (that is, a secondary conductor) is located on station ST, and the cart is caused to travel rightward in the drawing from this position. In this case, the control device 14 supplies power to the primary coil 11 to move the secondary conductor 2 to the right, confirms that the trolley is located at the station ST by the output signal of the sensor 12, and moves the secondary conductor 2 to the right. Power is supplied to the closest one of the primary coils on the right, that is, the primary coil [a.

As a result, the secondary conductor 2 moves to the right and the primary coil Ic
The magnetic force of the primary coil 1a continues to move in the desired direction. On the other hand, when the secondary conductor 2 reaches the position of the primary coil 1a, the current detection circuit I5 detects this from a change in the feeding current and supplies a detection signal to the control device 14. As a result, the control device 14 stops power supply to the primary coil 11, and then starts power supply to the primary coil 1b. Further, when the secondary conductor 2 moves and reaches the position of the primary coil lb, the current detection circuit 15 detects this and supplies a detection signal to the control device 14. As a result, the control device 14
stops power supply to the primary coil Ic and starts power supply to the primary coil Ic. From now on, the control circuit 14 will be
Power feeding to the primary coil on the side in the traveling direction of the secondary conductor 2 is started, and power feeding to the primary coil through which the secondary conductor 2 has passed is stopped +J=.

That is, based on the detection result of the current detection circuit 15, when the secondary conductor is located above any of the primary coils, the control device 14 starts feeding power to the primary coil in front of the vehicle in the traveling direction. At the same time, the power supply to the primary coil at the rear in the traveling direction is stopped.

Note that the control method in this embodiment is not limited to the method described above. For example, the current detection circuit [5] detects the moment when the current passes the primary coil (the moment when there is no load), and at this moment, the power supply to the same primary coil is detected. Control may also be performed such that when the primary coil is stopped, the power supply to the primary coil located ahead in the traveling direction is started. In short, the primary coils on the track may be sequentially switched according to the running direction of the secondary conductor.

According to the above embodiment, each station only needs to have one sensor for detecting the trolley, which has the advantage of reducing the number of sensors and reducing costs compared to conventional devices. It will be done.

"Effects of the Invention" As explained above, according to this invention, the orbit? -, I\-1-Nil (14 coils of t, 1iir, ii'! 11i1+ A trolley installed so that it can run freely along the road, and a secondary conductor attached to this trolley. In the linear motor type conveyance device, the power supply to each of the primary coils is controlled to provide a thrust to the secondary conductor. A secondary conductor detection circuit detects whether the secondary conductor is placed above each primary coil at an angle of 7 degrees, and based on the detection result of this secondary conductor detection circuit,
A sequence control unit that supplies power to the primary coil where the secondary conductor is detected to be located, and sequentially switches power supply to the primary coils located before and after the front and rear bodies of the front and back bodies in accordance with the running direction thereof. Since it is equipped with
It is possible to eliminate the need for sensors for detecting trolleys, which were required on two sides for each primary coil, and thereby extremely reduce the possibility of failure of the cables wired between each primary coil and the control unit. Benefits can be obtained. Therefore, not only can costs be reduced, but also frequent effects such as a reduction in Jf on wiring and a reduction in wiring space can be obtained.

・1 Drawing No. 11if Qj "L 1j':t! Bright FIG. 1 does not show the structure of an embodiment of the present invention, but is a schematic block diagram,
FIG. 2 is a sectional view showing the relationship between the truck and the track in the same embodiment, and FIG. 3 is a schematic configuration diagram showing the configuration of a conventional linear motor conveyance device.

Ia, Ib, Ic...Primary coil, 2
...Secondary conductor, 14...Control device (Noken control unit), 15...N flow detection circuit (Secondary conductor detection circuit).

Claims (1)

[Claims] A plurality of primary coils provided along a track, a cart provided movably along the track, and a secondary conductor attached to the cart are provided, and power supply to each of the primary coils is controlled. In the linear motor conveyance device that applies thrust to the secondary conductor, whether or not the secondary conductor is located above each of the primary coils is determined by detecting the value of the power supply current to each of the primary coils. Based on the secondary conductor detection circuit that detects and the detection result of this secondary conductor detection circuit,
a sequence control unit that supplies power to the primary coil where the secondary conductor is detected to be located, and sequentially switches power supply to the primary coils located before and after the secondary conductor in accordance with the running direction; A linear motor type conveyance device characterized by comprising: