Transport apparatus
A conveying device detects an abnormality due to a change in the surface state of the conveying plane. The conveying device has a conveying plane for conveying thereabove a conveying container equipped with a magnetic body, a position detection unit for detecting the position of the conveying container above the conveying plane, a magnetic pole disposed below the conveying plane and equipped with a core and a coil, a drive unit for applying a voltage to the magnetic pole, and a calculation unit for controlling the drive unit. The calculation unit calculates the conveying speed of the conveying container on the basis of the position of the conveying container above the conveying plane and the time at which the conveying container passes through the position, and detects the surface state of the conveying plane on the basis of the calculated conveying speed of the conveying container.
1 . A transport apparatus comprising:
a plurality of transport containers, each transport container including a magnetic body;
a transport plane on which a plurality of transport containers are transported;
a position detector that detects respective positions of the transport containers on the transport plane;
a plurality of magnetic poles, which are arranged under the transport plane, each magnetic pole including a core and a coil;
a drive unit that applies a voltage to each magnetic pole; and
a calculation unit that controls the drive unit,
wherein the calculation unit is configured to:
calculate a transport speed of each transport container transported along a same route passing through a plurality of positions, based on the respective transport container passing through each position on the transport plane and a time at which the respective transport container passes through each position using an interval of time required for the respective transport container to move between ones of the plurality of magnetic poles in an acceleration region where the respective transport container accelerates from a first position to a second position, the transport speed being greatest at the second position among the positions the transport container passes through, and a distance between the magnetic poles in the acceleration region,
estimate a mass of each of the transport containers based on an average acceleration in the acceleration region of the transport containers,
compare the calculated transport speed of the respective transport containers and a reference transport speed of a reference transport container having a predetermined mass, and
detect a surface state of the transport plane based on a difference in the mass of the transport containers, and the respective comparisons of the transport speeds of the transport containers and the reference transport speed.
2 . The transport apparatus according to claim 1 ,
wherein each position detector is arranged to transmit a time at which a magnetic body passes through or reaches the magnetic poles to the calculation unit.
3 . The transport apparatus according to claim 1 ,
wherein the calculation unit records the positions of the magnetic poles and the time, and calculates the transport speeds of the transport containers based on the positions and the time.
4 . The transport apparatus according to claim 1 ,
wherein a reference surface state of the transport plane is detected using the reference transport container, the reference transport container having a constant mass and a same shape and magnetic force of the magnetic bodies of the transport containers.
5 . The transport apparatus according to claim 1 ,
further comprising a monitoring system that displays a change in the surface state of the transport plane.
6 . A transport apparatus comprising:
a plurality of transport containers, each transport container having a magnetic body;
a transport plane on which the plurality of transport containers are transported;
a plurality of magnetic poles that are arranged under the transport plane, each magnetic pole including a core and a coil;
a drive unit that applies a voltage to the magnetic poles; and a calculation unit that controls the drive unit,
wherein the drive unit detects a current that flows through the magnetic poles, and
wherein the calculation unit is configured to:
detect respective positions of the transport containers on the transport plane based on the detected currents, calculate respective transport speeds of the transport containers transported along a same route passing through a plurality of positions, based on the respective transport passing through each position on the transport plane and a time at which the respective transport container passes through each position and using an interval of time required for the transport containers to move between ones of the plurality of magnetic poles in an acceleration region where the respective transport containers accelerate from a first position to a second position, the transport speed being greatest at the second position among positions the transport container passes through, and a distance between the magnetic poles in the acceleration region,
estimate a mass of each of the transport containers based on an average acceleration in the acceleration region of the transport containers,
compare the calculated transport speed of the respective transport containers and a reference transport speed of a reference transport container having a predetermined mass, and
detect a surface state of the transport plane based on a difference in the mass of the transport containers, and the respective comparisons of the transport speeds of the transport containers and the reference transport speed.
7 . The transport apparatus according to claim 6 ,
wherein the drive unit detects a current that flows through a resistance connected to the coils.
8 . The transport apparatus according to claim 6 ,
wherein the voltage applied to the magnetic poles by the drive unit is a voltage pulse, and the current detected by the drive unit is a current waveform.
9 . The transport apparatus according to claim 6 ,
comprising a database that stores a current flowing through the magnetic poles, a voltage applied to the magnetic poles, respective positions of the transport containers on the transport plane, a time at which the transport containers pass through the respective positions, transport speeds of the transport containers, and a surface state of the transport plane.
10 . The transport apparatus according claim 9 ,
wherein the current flowing through the magnetic poles, the voltage applied to the magnetic poles, the respective positions of the transport containers on the transport plane, the time at which the transport containers pass through the respective positions, the transport speeds of the transport containers, and the surface state of the transport plane are transmitted to the database by a communication device.