JPH06311609A - Levitation transfer system - Google Patents

Abstract

PURPOSE:To save the space at a branch part in a transfer path while stabilizing the running of carrier thereat by providing a main line, a branch line substantially perpendicular to the main line, and a stretching part formed at a specific position. CONSTITUTION:When a carrier 2 arrives at a branch part A, the carrier 2 is subjected to noncontact brake force. When the carrier 2 is pushed out in the direction of branch lines 33a, 33b after stoppage thereof, the carrier 2 begins to run in the substantially normal direction, i.e., along the branch lines 33a, 33b, while sustaining the orientation of the vehicle body. Furthermore, a part 38 stretching oppositely to the extending direction of the branches 33a, 33b is provided on the side of the main,1ines 32a, 32b oppositely to the branch lines 33a, 33b in order to relax the difference of magnetic resistance of a guide rail 1 thus suppressing the vibration. This constitution saves the space at the branch part A of a carrying path while stabilizing the running of carrier thereat.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a levitation type conveyance device suitable for conveying small articles, and more particularly to a space saving of a branch portion in a conveying path and a stable traveling at the branch portion. The present invention relates to a floating transfer device.

[0002]

2. Description of the Related Art In recent years, as a part of office automation and factory automation, slips, documents, cash, samples and the like have been moved between a plurality of points in a building using a carrier device.

The transport device for such an application should not impair the environment of the office, and is required to have low noise without generation of dust. Therefore, this type of transfer device is configured to support the transfer vehicle in a non-contact manner with respect to the guide rail.

In order to support the carrier vehicle in a non-contact manner, it is general to use pneumatic force or magnetic force. Above all, the method of supporting the carrier vehicle by using magnetic attraction force follows the guide rail. It is considered to be the most promising support method due to its excellent performance and noise reduction effect.

By the way, in a normal office environment, since many obstacles exist, the construction of the transport path is often complicated. Further, there are various destinations of a plurality of transport vehicles on the transport path, and it is necessary to form the transport paths so that the transport vehicles do not interfere with each other on the transport path as much as possible, and to control the traveling of each transport vehicle. Considering these points,
It is desirable to provide a number of branching portions on the transport path and divide the plurality of transport vehicles on the main line into branch lines passing through the respective transport destinations.

However, in this case, when it is attempted to branch the transporting vehicle while the vehicle is running, as is usually done, a curved section is provided at the branching portion or a part of the track is mechanically moved in the branching direction. Therefore, the branch portion becomes large, and the space saving of the transport path is significantly impaired. Further, in a small office environment, it is not possible to provide a large number of such branching parts, so that the probability that a plurality of transport vehicles will interfere with each other on the transport path eventually increases. However, there is a problem that it takes time to move each carrier to the destination because the traveling of the vehicle is controlled.

[0007]

As described above, in the conventional levitation type transporting apparatus, even if an attempt is made to branch the transporting path, the branching portion becomes large, so that space saving cannot be achieved. As a result, there was a problem that the number of branches was suppressed.

[0008] Therefore, the present invention provides a levitation type transporting device which can save space at a branching portion, can provide a required number of branching portions, and can stably run a transport vehicle at the branching portion. It is intended to be provided.

[0009]

In order to achieve the above object, the present invention provides a guide rail made of a ferromagnetic material,
The transport vehicle is arranged so as to be able to travel along the lower surface of the guide rail, and an electromagnet mounted on the transport vehicle and opposed to the lower surface of the guide rail via a gap is provided. A magnetic support unit for levitating the magnetic force, control means for controlling an exciting current of the electromagnet to stabilize a magnetic circuit through which a magnetic flux generated in the magnetic support unit passes, In a levitation type conveyance device including a driving means for applying a driving force to a contact, the guide rail has a main line, a branch line branching from the main line at a substantially right angle, and the branch line branches at a side portion of the main line. It is characterized in that the side surface portion located on the side opposite to the side surface portion includes a projecting portion formed to extend in a direction opposite to the direction in which the branch line extends.

[0010]

When the transport vehicle advances from the main line to the branch line, when the transport vehicle approaches the branch portion, the driving device applies a braking force to the transport vehicle in a non-contact manner. After the carrier stops,
When the transport vehicle is pushed out in the branch line direction by the drive device, the transport vehicle travels along the branch line in a direction substantially 90 ° with respect to the traveling direction up to now, while keeping the orientation of the vehicle body.
That is, the carrier moves laterally along the branch line. Therefore, it is possible to change the direction of the carrier vehicle by 90 ° with a minimum amount of movement, and in the end, a large space is not required at the branching portion.

Further, when the carrier vehicle advances along the main line as it is without advancing to the branch line, when the carrier vehicle approaches a branch portion, the guide rail made of a ferromagnetic material forming the branch portion is formed. , Which is magnetically asymmetrical to the path of the carrier, receives a force that causes the carrier to be temporarily pulled toward the branch line due to the difference in magnetic resistance. Tries to proceed while vibrating in the direction orthogonal to the path. However, in the device of the present invention, since the side portion of the main line that is located on the side opposite to the side portion where the branch line branches off is provided with the overhang portion that extends in the direction opposite to the direction in which the branch line extends, The difference in magnetic resistance described above can be alleviated, and the occurrence of vibration described above can be suppressed. Therefore, it is possible to prevent the unstable traveling of the carrier caused by the presence of the branch portion.

[0012]

Embodiments will be described below with reference to the drawings. FIG. 1 shows a guide rail in a levitation type conveyance device according to an embodiment of the present invention, a branch portion A where a branch line branches from the main line, and FIG. 2 shows a conveyance vehicle approaching the branch portion A. The state is shown.

In this device, a carrier 2 is arranged below a ferromagnetic guide rail 1 laid in an office space or the like so as to avoid obstacles so that it can travel along the guide rail 1. A magnetic force attracting means for guiding the guide rail 1 of the carrier 2 supports the carrier 2 in a non-contact state with the guide rail 1, and a moving force applying means (not shown) provided along the guide rail 1 at predetermined intervals. The (drive means) is configured to drive the transport vehicle 2 in a non-contact manner. Further, this device includes a branch portion A of a guide rail 1 described later.
In FIG. 1, a vehicle traveling control device (not shown) for branching control of the vehicle 2 is provided.

As shown in FIG. 2, the transport vehicle 2 has a base 11 arranged so as to face the lower surface of the guide rail 1,
Four magnetic support units 12a, 12b, 12c, 12d arranged at the four corners of the upper surface of the base 11, respectively.
And a carrier body 13 supported on the lower surface of the base 11, and a secondary conductor 14 arranged at the center of the upper surface of the base 11.

Four magnetic support units 12a-12d
As shown in FIG. 3, is attached to the upper surface of the base 11 using bolts and a base 21 not shown. These magnetic support units 12a to 12d have two electromagnets 22 and 23 arranged on a line orthogonal to the main traveling direction of the carrier 2 shown by the arrow in FIG. 2 so that the upper end thereof faces the lower surface of the guide rail 1. The permanent magnet 24 magnetically connects the lower side surfaces of the electromagnets 22 and 23, and is formed in a U shape as a whole.

Each electromagnet 22, 23 has a yoke 25 made of a ferromagnetic material and a coil 26 wound around the yoke 25.
It consists of and. Each coil 26 includes electromagnets 22, 2
They are connected in series so that the magnetic fluxes formed by 3 are added to each other. An optical gap sensor 27 that detects the gap length between the upper end surfaces of the electromagnets 22 and 23 and the lower surface of the guide rail 1 is attached to each of the magnetic support units 12a to 12d.

On the other hand, in the transport vehicle main body 13, a levitation stabilization control device (not shown) for controlling the exciting currents of the corresponding magnetic support units 12a to 12d based on the outputs of the four optical gap sensors 27, It is equipped with a constant voltage generator and a small-capacity power supply that is a power supply source.

The secondary conductor 14 is a movable body of a linear induction motor (not shown) which serves as the above-mentioned moving force imparting means, and three movable bodies of linear induction motors which are drive elements (described later) provided in the branch portion A. When the apparatus is in operation, it is arranged at a height facing the stators of these linear induction motors with a slight gap.

On the other hand, the guide rail 1 is formed with an inverted U-shaped cross section, and a track frame 31 for protecting the moving space of the carrier 2.
It is installed on the lower surface of the upper wall of. The guide rail 1 has two main lines 32a and 32b laid in parallel so as to go around the office space, and these main lines 3 at the branch portion A.
Two branch lines 33a, 33b laid in parallel so as to branch from 2a, 32b at a substantially right angle, and these main lines 32a,
32b and the branch lines 33a and 33b are connected to each other by a well-shaped connecting plate 34 which is connected by a predetermined method.

The main lines 32a and 32b are the magnetic support units 12b (12d) and 12 on the left and right in the traveling direction of the main line.
a (12c) is formed at an interval that can be located just on the lower side and in the same width as the magnetic support units 12a to 12d. In addition, the branch lines 33a and 33b are provided on the front and rear magnetic support units 12a (12b) and 12c in the main line traveling direction.
(12d) are formed at intervals so that they can be located just on the lower side and have the same width as the thickness of the magnetic support units 12a to 12d. The main lines 32a and 32b and the branch lines 33a and 33b have a divided structure in order to facilitate the installation work in the office.

The coupling plate 34 is made of a ferromagnetic material, and as shown in FIG. 4, main line coupling portions 35a and 35b having the same width and the same spacing as the main lines 32a and 32b, and the branch line 33.
a and 33b, branch line coupling portions 36a and 3 having the same width and the same interval
6b and 6b are connected at a substantially right angle.

A predetermined padding portion 37 is provided at a portion B where the branch line coupling portions 36a and 36b are connected to the main line coupling portions 35a and 35b. Further, on the side surface portion of the side surface portion of the coupling plate 34, which is located on the side opposite to the branch line extending direction, an overhang portion 38 is integrally formed so as to project outward by a predetermined length.

This overhanging portion 38 is used for the magnetic support unit 1.
When 2a to 12d approach the portion B, the magnetic support units 12a to 12b are prevented from being pulled to the branch line side having a low magnetic resistance and vibrating the carrier vehicle 2. The purpose is to reduce the magnetic resistance.

In the branch portion A, a square hole 41 slightly larger than the central hole 39 of the connecting plate 34 is bored in the upper wall of the track frame 31, as shown in FIG. Three linear induction motor stators 43a, 43b, 43c are fixed to the lower surface of the support plate 42 that closes the rectangular hole 41 from the upper surface so as to face the central hole 39 of the coupling plate 34.

These stators 43a to 43c are used for the transport vehicle 2.
Together with the secondary conductor 14 attached to the drive element in the branch portion A described above. Of these three stators 43a to 43c, the two stators 43a and 43c arranged at both ends in the traveling direction of the main line apply a driving force in the branch line direction to the secondary conductor 14 of the transport vehicle 2. In addition, the stator 43b at the center provides a driving force in the main line direction to the secondary conductor 14.

On the other hand, as shown in FIG. 4, optical sensors 44a, 44b and 44c are arranged at the front left and right sides and the center portion on the right side of the central hole 39 of the coupling plate 34 in the main traveling direction, respectively. These optical sensors 44a to 44c are reflection type optical sensors that detect the secondary conductor 14 of the transport vehicle 2. These three optical sensors 44a to 44c detect the position of the transport vehicle 2 with respect to the branch portion A, and based on this, the three stators 43a to 43 in the transport vehicle travel control device described above.
c is controlled. FIG. 5 shows a configuration example for realizing the control in the branch unit A.

That is, the detection signals from the optical sensors 44a to 44c are input to the microcomputer 51. On the other hand, a series circuit of three stators 43a to 43c and thyristor switches 54a to 54c is connected in parallel to the three-phase AC power source 52 via a slidac 53. The microcomputer 51 has three optical sensors 44.
a-44c based on the present detection status and the past detection information stored in the internal memory, the thyristor switch 54a.
To 54c are selectively switched to the stators 43a to 4a.
A power supply voltage is selectively supplied to 3c. At this time, the traveling directions of the moving magnetic fields of the stators 43a to 43c are also controlled at the same time.

Next, the operation of the levitation type transport device configured as described above will be described. When the device is activated, the control device causes the electromagnets 22 and 23 to generate a magnetic flux in the same direction or in the opposite direction to the magnetic flux generated by the permanent magnet 24, and at the same time, the magnetic support units 12a to 12d and the guide rail 1 are generated.
To maintain a predetermined air gap between the excitation coil 26 and
Control the current flowing through. Thereby, as shown in FIG. 3, the permanent magnet 24, the yoke 25, the void P, and the guide rail 1 are provided.
A magnetic circuit including a path of the void P, the yoke 25, and the permanent magnet 24 is formed. The gap length is set so that the weight of the supported body such as the transport vehicle 2 and the magnetic attraction force between the magnetic support units 12a to 12d and the guide rail 1 due to the magnetomotive force of the permanent magnet 24 are just balanced. It The controller is
The excitation current of the electromagnets 22 and 23 is controlled to maintain this gap length. As a result, so-called zero power control is performed.

Now, assuming that the transport vehicle 2 is located directly below the stator of the linear induction motor (not shown) that is the moving force applying means,
When the stator is biased, the secondary conductor 14 receives an electromagnetic force from the stator. As a result, the transport vehicle 2 starts traveling along the main lines 32a and 32b of the guide rail 1 in a state of being levitated by the magnetic force. If the stator is arranged again until the carriage 2 is completely stationary due to the influence of air resistance or the like, the carriage 2 is urged again and continues traveling along the main lines 32a and 32b.

Now, at the branch A, the carrier 2 is moved to the main line 32.
It is assumed that a command for advancing from a, 32b to branch lines 33a, 33b is given to the vehicle traveling control device. When the transport vehicle 2 approaches the branch portion A, the optical sensor 44c first detects the secondary conductor 14 as shown in FIG. The microcomputer 51 urges only the stator 43b in the direction of the arrow in the drawing to drive the transport vehicle 2 in the main line traveling direction. When the transport vehicle 2 moves to the position shown in FIG. 7, all of the optical sensors 44a to 44c detect the secondary conductor 14, so that the microcomputer 51 stops the biasing of the stator 43b and the stators 43a and 43c. Is urged toward the branch line. As a result, when the speed of the transport vehicle 2 is not too high, the transport vehicle 2 stops when the magnetic support units 12a to 12d cross the portion B of the coupling plate 34 having the smallest magnetic resistance. However, when the speed of the carrier 2 is high,
As shown in FIG. 8, the guided vehicle 2 passes through the branch portion A. At this time, since the optical sensor 44c does not detect the secondary conductor 14, the microcomputer 51 causes the stator 43 to
B is urged to apply a driving force to the transport vehicle 2 in a direction opposite to the traveling direction of the main line. As a result, when the transport vehicle 2 returns to the branch portion A, all of the optical sensors 44a to 44c detect the secondary conductor 14, so that the microcomputer 51 causes the stator 43 to operate.
Energize a and 43c. As a result, the transport vehicle 2 moves along the branch lines 33a and 33b in the horizontal direction as shown in FIG. Then, when all the optical sensors 44a to 44c no longer detect the secondary conductor 14, the stators 44a, 44
The excitation of c is stopped. Even when the transport vehicle 2 enters the branch portion A from the right side in the figure or from the lower side in the figure, the transport vehicle 2 can be advanced to the target route by the same excitation control.

The above description is based on the description that the carrier 2
This is the case when the traveling direction of the car is converted by 90 degrees,
The transport vehicle 2 without stopping at the main lines 32a, 32b.
Sometimes run along the line. In this case, the guided vehicle 2 can be stably passed without being influenced by the presence of the branch portion A.

The reason for this will be described with reference to FIG.
In FIG. 10 (a), the main line 32a and the magnetic support unit 12 are
b and the main line connecting portion 35a and the branch line connecting portion 36a of the connecting plate 34, the carrier vehicle, that is, the magnetic support unit 12 is used.
It shows how b invades the branch portion A.

The magnetic support unit 12b moves to X ₁ position, X ₂ position, and X ₃ position in the figure with the passage of time. When the magnetic support unit 12b is at the X ₁ position, the center line of the magnetic support unit 12b in the direction orthogonal to the traveling direction and the center line of the main line 32a in the direction orthogonal to the traveling direction are substantially aligned with each other. Therefore, for this reason, the upper end surface of each yoke 25 of the magnetic support unit 12b and the main line 32 are
The reluctance with a is almost balanced. Therefore, almost no force acts on the magnetic support unit 12b in the direction orthogonal to the traveling direction.

When the magnetic support unit 12b reaches the X ₂ position, the branch line connecting portions 36a are provided on both sides in the traveling direction at this position.
Since the overhanging portion 38 and the overhanging portion 38 exist, the so-called solid angle at which the ferromagnetic material can be seen from the upper end surface of each yoke 25 of the magnetic support unit 12b rapidly increases. In this case, since the branch line coupling portion 36a and the overhanging portion 38 are present on both sides of the magnetic support unit 12b as a boundary, the increase in the compatibility angle is about the same. Therefore, the magnetic resistance between the upper end surface of each yoke 25 and the main line side is almost balanced.
Therefore, the force in the direction orthogonal to the traveling direction hardly acts on the magnetic support unit 12b.

When the magnetic support unit 12b arrives at the X ₃ position, the same state as when the magnetic support unit 12b is located at the X ₁ position is formed, so that the magnetic force between the upper end surface of each yoke 25 of the magnetic support unit 12b and the main line side is increased. The resistance is almost balanced. Therefore, almost no force acts on the magnetic support unit 12b in the direction orthogonal to the traveling direction.

After all, the overhanging portion 38 has the branch line connecting portion 36a.
Prevents the magnetic resistance from becoming unbalanced due to the presence of. As a result, as shown by the broken line arrow in FIG. 10 (a), the branch portion A is stabilized in a state in which almost no force acts on the magnetic support unit 12b in the direction orthogonal to the traveling direction, that is, in a state in which no rolling occurs. Can be passed.

When the overhanging portion 38 does not exist, as shown in FIG. 10 (b), the magnetic support unit 12b is formed.
A force in a direction orthogonal to the traveling direction is applied to the carriage 2, and as a result, the carrier 2 passes through the branch portion A while undergoing severe lateral rolling.

That is, the magnetic support unit 12b is X ₂
When reaching the position, since the branch line coupling portion 36a is present only on one side in the traveling direction at this position, the so-called solid angle where the ferromagnetic material can be seen from the upper end surface of each yoke 25 of the magnetic support unit 12b is the traveling direction. Only the yoke located on the right side of the direction increases rapidly. That is, the magnetic resistance between the yoke located on the right side in the traveling direction and the main line side is smaller than the magnetic resistance between the yoke located on the left side in the traveling direction and the main line side. For this reason, a pulling force is applied to the magnetic support unit 12b toward the branch line connecting portion 36a, and the magnetic support unit 12b moves to the branch line connecting portion 36a as shown in FIG. 10 (b).
Move to the side.

Then, when the magnetic support unit 12b passes the X ₂ position, the magnetic resistance is unbalanced again, so that a force acts to return the magnetic support unit 12b to the original position. This force causes the magnetic support unit 12b to return to its original position, but an overshoot phenomenon that normally passes through the original position occurs, the magnetic support unit 12b moves in the opposite direction again, and eventually the magnetic support unit 12b. Is a zigzag route as shown by the dashed arrow in the figure,
In other words, it progresses while rolling. Therefore, stable traveling cannot be expected without the overhanging portion 38.

As described above, according to the present embodiment, the space required for branching the transport vehicle 2 can be made very small, and along with this, a large number of branches can be provided relatively densely in the transport path. Therefore, it is possible to reduce the probability that the transport routes of the multiple transport vehicles 2 to the transport destination interfere with each other. In addition, since the transport vehicle can be branched while it is in a floating state and the track is not moved, the original purpose of the levitation type carrier device is to prevent the generation of noise and dust at the time of branching. Does not hurt at all.

Further, a bulge extending in a direction opposite to the extending direction of the branch lines 33a, 33b is located on the side face portion located on the side opposite to the side face portion where the branch lines 33a, 33b branch off on the side face portions of the main lines 32a, 32b. Since the portion 38 is provided, it is possible to reduce the above-mentioned difference in magnetic resistance and prevent unstable traveling of the transport vehicle 2 caused by the presence of the branch portion A.

The present invention is not limited to the above embodiment. As shown in FIG. 11, a linear induction motor as a drive element includes a stator 61 for driving in the main line direction.
It is also possible to dispose a and 61c at both ends in the main line direction and dispose the stator 61b for driving the branch line direction in the center. In this case, the range in which the carriage 2 can be pulled back when the vehicle 2 passes the branch portion A can be expanded more than in the above case. Further, as shown in FIG. 12, the driving device may be one in which a plurality of air nozzles 62 are arranged in three directions to obtain driving by blowing air. In this case, a space for arranging the stator is not required, so that the reinforcing member 63 is provided in the central hole 39 of the coupling plate 34.
Can also be integrally formed. Further, the stator of the linear induction motor for two-way conveyance may be arranged so as to face the central hole 39 of the coupling plate 34 as a drive element. In this case, the space for arranging the stator can be greatly reduced.

Further, the present invention is not limited to the case where the number of guide rails is two, and can be applied to the case where the number of guide rails is one, and more than three. Needless to say. Further, the present invention is also applicable to a levitation-type transfer device using only an electromagnet as a magnetic support unit.

[0044]

As described above, according to the present invention,
It is possible to save space at the branching portion, make it possible to provide the required number of branching portions, and it is possible to stably run the carrier vehicle at the branching portion.

[Brief description of drawings]

FIG. 1 is a perspective view showing only a portion where a branch line is branched from a main line in a levitation type transporting apparatus according to an embodiment of the present invention.

FIG. 2 is a diagram showing a state in which a carrier vehicle is approaching the branch portion.

FIG. 3 is a vertical sectional view of a magnetic support unit in the same device.

FIG. 4 is a plan view of the device with a part of a branch portion omitted.

FIG. 5 is a block diagram of a circuit that realizes branch control in the device.

FIG. 6 is a partial plan view for time-sequentially explaining the operation of the apparatus when branching.

FIG. 7 is a partial plan view for time-sequentially explaining the operation of the apparatus when branching.

FIG. 8 is a partial plan view for time-sequentially explaining the operation of the device when branching.

FIG. 9 is a partial plan view for time-sequentially explaining the operation of the device when branching.

FIG. 10 is a view for explaining the action of an overhanging portion provided at a branch portion of the same device.

FIG. 11 is a partial plan view showing an essential part of another embodiment of the present invention.

FIG. 12 is a partial plan view showing an essential part of still another embodiment of the present invention.

[Explanation of symbols]

1 ... Guide rail 2 ... Transport vehicle 11 ... Base 12a-12d
... Magnetic support unit 13 ... Car body 14 ... Secondary conductor 31 ... Track frames 32a, 32b
... Main line 33a, 33b ... Branch line 34 ... Coupling plate 35a, 35b ... Main line coupling part 36a, 36b
... Branch line coupling portion 38 ... Overhang portion 43a to 43c, 61
a-61c ... Stator 44a-44c ... Optical sensor 62 ... Air nozzle A ... Branch part B ... Intersection part

Claims (4)

[Claims] Claim: What is claimed is: 1. A guide rail made of a ferromagnetic material, a carrier arranged so as to run along the lower surface of the guide rail, and a carrier mounted on the carrier via a gap between the lower surface of the guide rail and the guide rail. And one or more magnetic support units for magnetically levitating the carrier with respect to the guide rails, and a magnetic flux generated by the magnetic support unit that controls the exciting current of the electromagnets. In a levitation type conveyance device comprising a control means for stabilizing a circuit and a drive means for applying a driving force to the conveyance vehicle in a non-contact manner, the guide rail branches off from the main line at a substantially right angle. A branch line; and a projecting portion formed on a side surface portion of the side surface of the main line, which is located on a side opposite to a side surface portion on which the branch line is branched, extending in a direction opposite to a direction in which the branch line extends. Floating type transport device characterized in that 2. The driving means includes a first element for applying a braking force or a propulsive force to the vehicle traveling on the main line at a portion where the branch line branches from the main line, and the vehicle for the main line. The levitation type conveyance device according to claim 1, further comprising: a second element that applies a propulsive force to the conveyance vehicle in a branch line direction when the conveyance type is stopped. 3. The first element and the second element are
The levitation type conveyance device according to claim 2, wherein each of the levitation type conveyance devices is constituted by a stator of a linear induction motor. 4. The first element and the second element are
The levitation-type conveyance device according to claim 2, wherein the levitation-type conveyance device is controlled based on an output of a detector that detects a positional relationship between the main line and the branch line and the conveyance vehicle.