JPH0757042B2 - Floating carrier - Google Patents

Description

Description: TECHNICAL FIELD OF THE INVENTION The present invention relates to a levitation type conveyance device suitable for conveying small articles, and particularly to a levitation type conveyance device adapted to efficiently apply propulsive force to a conveyance vehicle. Regarding

[Technical background of the invention and its problems]

In recent years, as 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 conveying device used for such an application should not damage the environment of the office, and is required to have low noise without generation of dust or the like. For this reason, this type of transport device is configured to support the transport vehicle in a non-contact manner with respect to the guide rail. In order to support the carrier without contact, it is common to use air or magnetism. Among them, the method of magnetically supporting the carrier is excellent in following the guide rails and reducing noise. And is considered the most promising support system.

By the way, in order to run a carrier that is levitated by such a conventional magnetic support system, the secondary conductor plate of a single-sided linear induction motor is attached to the carrier, and the stator of the motor is placed on the track side. The method of applying a thrust required for acceleration and deceleration to a carrier vehicle is most widely used because of its simplified structure.

The one-sided linear induction motor generally has a structure in which a secondary conductor plate is lined with an iron plate and the magnetic flux generated by the stator is concentrated on the secondary conductor to obtain a large thrust. However, when a secondary conductor plate lined with an iron plate is attached to a carrier as described above, a strong magnetic attraction force acts between the stator and the iron plate, which makes magnetic levitation of the carrier extremely difficult. was there. It is also possible to remove the iron plate so that this attractive force is not generated, but if this is done, the magnetic flux generated by the stator will not concentrate on the secondary conductor, and the gap length between the stator and the secondary conductor will be reduced. Unless it is extremely short, a large thrust cannot be obtained. Furthermore, if the void length is extremely shortened,
There also arises a problem that a traveling transport vehicle may collide with the stator.

[Object of the Invention]

The present invention has been made in view of such circumstances, and an object of the present invention is to provide a levitation type conveyance device capable of giving a large acceleration / deceleration force to a conveyance vehicle without adversely affecting the magnetic levitation state of the conveyance vehicle. To provide.

[Outline of Invention]

According to the present invention, at least a lower surface portion is formed of a ferromagnetic material and is arranged on a fixed side, a guide vehicle arranged so as to be able to travel along the guide rail, and a lower surface of the guide rail and a gap therebetween. An electromagnet arranged to face each other, and a permanent magnet interposed in a magnetic circuit formed by the electromagnet, the guide rail, and the air gap to supply a magnetomotive force necessary for levitating the carrier, and And / or a plurality of magnetic support units mounted on the carrier, control means for controlling the exciting current of the electromagnet to stabilize the magnetic circuit in a state where the current flowing through the electromagnet becomes zero, and the carrier. In a levitation type conveyance device including a linear induction motor that applies a thrust force along the guide rail, the linear induction motor includes a secondary conductor provided on the conveyance vehicle, and The secondary conductor is provided between a plurality of stators scattered on the fixed side along the guide rail so as to face the secondary conductor, and between the stators facing and facing the stators. Is provided with a plurality of ferromagnetic bodies arranged on the fixed side with a gap for allowing the non-contact to pass therethrough.

〔The invention's effect〕

According to the present invention, even if a magnetic attraction force acts between the ferromagnetic body for concentrating the magnetic flux in the secondary conductor and the stator of the one-sided linear induction motor, both are fixed to the fixed side. Therefore, the suction force does not affect the transport vehicle at all. Further, the magnetic flux emitted from the stator goes to the opposing ferromagnetic body, travels in this ferromagnetic body, and then goes from the ferromagnetic body to the stator. Therefore, when the secondary conductor enters the space where the stator and the ferromagnetic material face each other, the magnetic flux penetrates the secondary conductor so that the magnetic flux is substantially orthogonal to the traveling direction of the secondary conductor, and this penetration causes the secondary conductor to pass through. The flow path of the eddy current induced in the conductor is located in the plane orthogonal to the direction of the magnetic flux penetrating therethrough. Therefore, almost no force acts on the secondary conductor except in the direction parallel to the stator. Therefore, the floating running state of the carrier can be stabilized.

Moreover, by arranging the ferromagnetic material on the fixed side in this way, the weight of the transport vehicle will be lighter than that when the ferromagnetic material of the secondary conductor is lined, so the load on the transport vehicle must be increased accordingly. You can

In the present invention, the magnetic flux can be concentrated on the secondary conductor by the ferromagnetic material, and a large acceleration / deceleration force can be obtained. Therefore, the climbing ability of the carrier vehicle can be improved. As a result, a complicated transportation path can be set, which contributes to space saving.

Example of Invention

Hereinafter, a levitation type conveyance device according to an embodiment of the present invention will be described with reference to the drawings.

In FIG. 1 to FIG. 3, reference numeral 1 is a track frame having a reverse U-shaped cross section and laid so as to avoid obstacles in an office space, for example. Two guide rails 2a and 2b are laid parallel to each other on the lower surface of the upper wall of the track frame 1, and emergency guides 3a and 3b each having a U-shaped cross section are formed on the inner surface of the side wall of the track frame 1 mutually. Are laid with the open sides facing each other. Below the guide rails 2a, 2b, a carrier vehicle 15 is arranged so as to be able to travel along the guide rails 2a, 2b. A plurality of vertically elongated holes 1a are formed in the central portion of the upper wall of the track frame 1 at a predetermined distance along the transport track, and the bottom surface of the top plate 4 that closes these holes 1a from the top surface of the track frame 1 is formed. In addition, the stator 16 of the linear induction motor is arranged so as to be accommodated in the hole 1a. Further, as shown in FIG. 2, ferromagnetic bodies 5a and 5b made of, for example, iron plates, which are opposed to the lower surface of the stator 16 through a predetermined gap, project from both side edges of the hole 1a of the track frame 1.

The guide rails 2a and 2b are formed by sticking a white vinyl tape 22 on the lower surface of an inverted U-shaped member 21 made of a ferromagnetic material, and have a split structure to facilitate the installation work in an office. Has become. The joint portion A of each member 21 is subjected to a predetermined joining process.

Next, the structure of the carrier vehicle 15 will be described. That is, the flat base 25 is arranged so as to face the lower surfaces of the guide rails 2a and 2b.
Are arranged. The base 25 is composed of two split plates 26a, 26b arranged in the traveling direction, and a connecting mechanism 27 for rotatably connecting the two split plates 26a, 26b in a plane orthogonal to the same traveling direction. There is. The connecting member 27 is for absorbing the deviation of the plane formed by the guide rails 2a and 2b due to the cant when passing through a curved transportation track having a small diameter. Each dividing plate 26a, 26
Above each central part of b, at the position of a height where the space between the stator 16 and the ferromagnetic bodies 5a, 5b can pass in a non-contact state between the stator 16 and the ferromagnetic bodies 5a, 5b at the time of operation of the device, the linear induction described above is provided. Secondary conductor plates 28a and 28b, which are movable elements of the electric motor, are arranged. These secondary conductor plates 28a, 28b are made of a non-magnetic material and are fixed to the split plates 26a, 26b via connecting plates 29a, 29b, respectively. At the four corners of the upper surface of this base 25 ,
A total of four magnetic support units 31 are mounted on each. These magnetic support units 31 use the bolts 32 and the pedestals 33 so that they can rotate on the upper surface of the base 25.
Installed on 25 . These magnetic support units 31, the optical gap sensor 34 for detecting the length of the gap between the lower surface of the unit 31 and the guide rails 2a, 2b are mounted. In addition, the connecting member 35
Containers 37, 38 for accommodating conveyed goods via a, 35b, 36a, 36b
Are installed respectively. And these containers 37,3
The control unit 41 for controlling each of the four magnetic support units 31 , the constant voltage generator 42, and the small-capacity power source 43 for supplying electric power to these units are installed in each of the eight units. Has been done. Further, at the four corners of the lower surface of the base 25 , for supporting the transport vehicle 15 in the vertical direction by contacting the inner surfaces of the upper and lower walls of the emergency guides 3a and 3b when the magnetic force of the magnetic support unit 31 is lost. Four vertical wheels 45a,
Four lateral wheels 45b for contacting the inner surfaces of the side walls of the emergency guides 3a and 3b and supporting the transport vehicle 15 in the left-right direction are attached.

The magnetic support unit 31 includes two electromagnets 51 and 52 arranged in a direction orthogonal to the traveling direction of the transport vehicle 15 such that the upper end faces the lower ends of the guide rails 2a and 2b, and these electromagnets.
It is composed of a permanent magnet 53 interposed between the lower side surfaces of 51 and 52 , and has a U shape as a whole. The electromagnets 51 , 52 are made of a ferromagnetic yoke 55 and the yoke 55.
It is composed of a coil 56 wound around 55, and each coil
56 are connected in series so that the magnetic fluxes formed by the electromagnets 51 and 52 are added to each other.

Further, the control device 41 is configured, for example, as shown in FIG. In this figure, arrows indicate signal paths and bar lines indicate power paths. This controller 41
Includes a sensor unit 61 for detecting a change in motion of the magnetomotive force or magnetic resistance or transport vehicle 15 in the magnetic circuit formed by the magnetic support units 31 mounted on the transport vehicle 15, the signal from the sensor unit 61 The calculation circuit 62 calculates the electric power to be supplied to the coil 56 on the basis of it, and the power amplifier 63 which supplies the electric power to the coil 56 on the basis of the signal from the calculation circuit 62. Control the four magnetic support units 41 respectively. Sensor section 61
Is a modulation circuit 64 that modulates the signal of the optical gap sensor 34 described above to suppress the influence of external noise, and the coil.
It is composed of a current detector 65 that detects the current value of 56. The arithmetic circuit 62, on the one hand, introduces the signal from the optical gap sensor 34 via a modulator circuit 64 and a subtractor 66
The gap length setting value z ₀ is subtracted by, and the output of the subtractor 66 is guided to the feedback gain compensators 68 and 69 directly or via the differentiator 67, and on the other hand, the signal from the current detector 65 is sent. It is introduced to the feedback gain compensator 70, further introduced from the current detector 65 and compared with the O signal by the subtractor 71, and then the integral compensator 72.
The signal compensated in (3) is compared with the addition output by the adder 73 of the three feedback gain compensators 68 to 70 in the subtractor 74, and the deviation is output to the power amplifier 63.

Further, the constant voltage generator 42 is interposed between the power supply 43 and the controller 41, and constantly supplies a constant current to the modulation circuit 64, the arithmetic circuit 62 and the optical gap sensor 34. The constant voltage generator 42 is for removing the influence of the voltage drop caused by the load fluctuation of the power supply 43 on the control device 41. The constant voltage generator 42 has a reference voltage generator 75 and an output signal of the reference voltage generator 75. On the basis of this, a current amplifier 76 is provided which constantly supplies a required current to the control device 41 at a constant voltage.

Next, the operation of the levitation type transporting apparatus according to this embodiment configured as described above will be described.

When the device is in a stopped state, the vertical wheels 45a of the transport vehicle 15 are in contact with the inner surface of one of the upper and lower walls of the emergency guides 3a and 3b. When the device is started in this state, the control device 41 causes the electromagnets 51 and 52 to generate a magnetic flux in the same direction or in the opposite direction to the magnetic flux generated by the permanent magnet 53, and causes the magnetic support unit 31 and the guide rails 2a and 2b to operate. The current flowing through the exciting coil 56 is controlled in order to maintain a predetermined air gap length. As a result, as shown in FIG.
A magnetic circuit is formed by the path of the yoke 55-the air gap P-the guide rails 2a, (2b) -the air gap P-the yoke 55-the permanent magnet 53. The magnetic flux Φ formed in this magnetic circuit is generated along a plane orthogonal to the traveling direction of the transport vehicle 15 . If the magnetic flux is generated in such a direction, the magnetic resistance does not decrease momentarily even when passing through the joint portion A of the guide rails 2a and 2b, and the vibration at the time of passing the joint can be reduced. The gap length is set so that the weight of the supported object such as the transport vehicle 15 and the magnetic attraction force between the magnetic support unit 31 and the guide rail 2a (2b) due to the magnetomotive force of the permanent magnet 53 are just balanced. To be done. The control device 41 controls the exciting current of the electromagnets 51 and 52 to maintain this gap length. As a result, so-called zero power control is performed.

Now, it is assumed that the magnetically levitated carrier 15 is directly below the stator 16 of the linear induction motor. When a three-phase AC voltage is applied to the three-phase winding applied to the stator 16, a moving magnetic field that proceeds in a specific direction is generated. Since the ferromagnetic bodies 5a and 5b are arranged on the side of the carrier 15 that faces the stator 16 via the secondary conductor plates 28a and 28b, the magnetic flux generated by the stator 16 is generated by the ferromagnetic body 5a. Focus on 55b. Therefore, as a result, the magnetic flux concentrates on the secondary conductor plates 28a and 28b. This magnetic flux penetrates the secondary conductor plates 28a, 28b, so that a current flows through the secondary conductor plates 28a, 28b. As a result, the carrier vehicle 15 receives an electromagnetic force due to the interaction between the electric current and the magnetic field, so that the carrier vehicle 15 remains in the magnetically levitated state.
Start traveling along b. If the stator 16 is arranged again until the carrier vehicle 15 is completely stationary due to the influence of air resistance or the like, the carrier vehicle 15 is urged again and continues to move along the guide rails 2a and 2b. This movement continues to the desired point. Thus, the transport vehicle 15 can be moved to the destination point in a non-contact state.

According to this embodiment, the stator winding is excited by exciting the stator winding.
Even if a magnetic attraction force is generated between the 16 and the ferromagnetic bodies 28a, 28b, the ferromagnetic bodies 5a, 5b are fixed on the fixed side, so that the relative positions of the two do not change, It has no effect on the running of car 15 . The magnetic flux is the secondary conductor 5a, 5
Since the secondary conductor plates 5a, 5b are penetrated so as to be substantially orthogonal to the traveling direction of b, almost no force acts on the secondary conductor plates 5a, 5b except in the direction parallel to the stator 16. Therefore, a large acceleration / deceleration force due to the concentration of the magnetic flux can be obtained while maintaining a stable floating state. If such a large acceleration / deceleration force is obtained, the climbing ability is improved, obstacles can be easily avoided in a small space, and space can be saved.

Further, since the weight of the carrier vehicle 15 can be reduced by not lining the ferromagnetic material on the secondary conductor plates 5a and 5b, the weight that can be carried within the set magnetic force range can be increased, and the carrying capacity can be increased. It also leads to improvement of.

The present invention is not limited to the above embodiment.

For example, FIG. 6 shows an example in which a linear induction motor is arranged below the transport vehicle. That is, 101a and 101b in the figure are guide rails laid parallel to a predetermined transport path. The carrier 102 is arranged above the guide rails 101a and 101b in a floating state, and a plurality of stators 103 of the linear induction motor are arranged below the carrier 102 along the carrier track. The carrier 102 connects a container 105, which is arranged on the upper surfaces of the guide rails 101a and 101b and has auxiliary wheels 104 on the lower surface, and a base 106, which is arranged on the lower surfaces of the guide rails 101a and 101b, with a connecting member 107. At the same time, at the four corners of the base 106,
The magnetic support unit 108 is arranged with its magnetic attraction surface facing the lower surfaces of the guide rails 101a and 101b, and a secondary conductor plate 109 is provided below the base 106 to form a non-magnetic spacer 11.
It is fixed through 0. Then, the secondary conductor plate 109
The stator 103 at a position facing the stator 103 via
A ferromagnetic material 111 that guides the magnetic flux of is arranged. This ferromagnetic material 111 is made of a non-magnetic spacer 112 and a stator 103.
It is fixed to.

Even with such a configuration, the effects of the present invention described above can be achieved. Further, in this case, since the linear induction motor and the guide rail are separately arranged, the work of laying the guide rail can be easily performed.

The secondary conductor is not limited to the plate-shaped one, and the present invention can be applied to, for example, an apparatus using a linear conductor. In addition, without providing a secondary conductor,
For example, a slit extending in the vertical direction may be formed in the center of the base on which the magnetic support unit is mounted, and the base may also be used as a secondary conductor.

In addition, the shapes of the container and other components can be variously changed without departing from the scope of the present invention.

[Brief description of drawings]

FIG. 1 is a perspective view showing a schematic configuration of a levitation type transporting apparatus according to an embodiment of the present invention, FIG. 2 is a vertical sectional view of the apparatus, and FIG. 3 is a side view in which the apparatus is partially cut away. FIG. 4 is a block diagram showing an electrical configuration of a control device of the apparatus, FIG. 5 is a view for explaining the operation of the apparatus, and FIG. 6 is a levitation type transfer apparatus according to another embodiment of the present invention. FIG. 1 …… Track frame, 2a, 2b, 101a, 101b …… Guide rail, 3a,
3b ...... emergency guide, 4 ...... tabletop, 5a, 5b ...... ferromagnetic, 15, 102 ...... transport vehicle, 16,103 ...... linear induction motor stators, 25,106 ...... base, 26a, 26b ...... Split plate, 27 ……
Coupling mechanism, 28a, 28b, 111 ... Secondary conductor plate, 34 ... Gap sensor, 37,38,105 ... Container, 41 ... Control device, 42 ...
… Constant voltage generator, 43 …… Power supply, 51, 52 …… Electromagnet, 53
…… Permanent magnet, 55 …… Yoke, 56 …… Coil, A …… Seam, P …… Void.

Claims (2)

[Claims] 1. A guide rail, at least a bottom surface of which is made of a ferromagnetic material and which is laid on a fixed side, a transporting vehicle which is movably arranged along the guide rail, and a gap between the guide rail and the guide rail. It is composed of electromagnets arranged so as to face each other, and a permanent magnet that intervenes in a magnetic circuit constituted by the electromagnets, the guide rails, and the air gap to supply a magnetomotive force necessary for levitating the carrier vehicle. And a magnetic support unit mounted on the carrier, control means for controlling the exciting current of the electromagnet to stabilize the magnetic circuit in a state where the current flowing through the electromagnet becomes zero, and the guide for the carrier. In a levitation type transfer device equipped with a linear induction motor that applies propulsive force along a rail,
The linear induction motor is provided with a secondary conductor provided on the transport vehicle, a plurality of stators arranged on the fixed side along the guide rail so as to face the secondary conductor, and a plurality of these stators. A plurality of ferromagnetic bodies arranged on the fixed side with a gap facing the stator and allowing the secondary conductor to pass through without contact between the stator and the stator. Floating type transport device. 2. The levitating transfer apparatus according to claim 1, wherein the secondary conductor is a conductor plate.