Method and apparatus for identifying a mover on a track

Patent metadata

Field	Value
Publication number	US-11643281-B2
Application number	US-202117154794-A
Country	US
Kind code	B2
Filing date	Jan 21, 2021
Priority date	Aug 9, 2017
Publication date	May 9, 2023
Grant date	May 9, 2023

Abstract

An improved system for determining the identification of movers in a motion control system is disclosed, where the motion control system includes multiple movers traveling on a track. The physical construction of at least one element of one of the movers is different on one mover than on each of the other movers. The control system for the movers detects the difference in construction and identifies the unique mover as a first mover. Each of the other movers along the track are assigned an identifier based on their relative position to the first mover. According to one embodiment, a position sensing system is utilized to identify the first mover. According to another embodiment, the drive system for the movers is utilized to identify the first mover. In still another embodiment, a combination of the position sensing system and the drive system is utilized to identify the first mover.

First claim

We claim:

1. A system for identifying a first mover, selected from a plurality of movers, wherein each of the plurality of movers is configured to travel along a track, the system comprising:
a plurality of magnets, wherein at least one magnet is mounted to each of the plurality of movers and generates a magnetic field; and
a plurality of sensors spaced along the track, wherein:
a first magnet, selected from the plurality of magnets, is mounted to the first mover,
each of the plurality of sensors generates a first signal having a first waveform corresponding to the magnetic field generated by the first magnet as the first mover passes the corresponding sensor,
each of the plurality of sensors generates a second signal having a second waveform corresponding to the magnetic field generated by each of the other magnets in the plurality of magnets as each of the plurality of movers other than the first mover passes the corresponding sensor, and
the first waveform is different than the second waveform.

2. The system of claim 1 wherein:
an air gap is defined between each of the plurality of magnets and each of the plurality of sensors as one of the plurality of movers passes one of the sensors,
a first air gap distance exists between the first magnet and each of the plurality of sensors,
a second air gap distance exists between each of the other magnets in the plurality of magnets and each of the plurality of sensors, and
the first air gap distance is different than the second air gap distance.

3. The system of claim 1 wherein:
each of the plurality of movers has a central axis extending generally orthogonal to a direction of travel along the track,
the first magnet is mounted to the first mover at a first distance from the central axis, and
each of the other magnets in the plurality of magnets is mounted to one of the other movers at a second distance from the central axis, where the first distance is different than the second distance.

4. The system of claim 3 further comprising a drive system including:
a plurality of coils mounted along the track, and
at least one drive magnet mounted to each mover, wherein:
each of the plurality of coils is energized by a high frequency voltage,
a position of the at least one drive magnet on each mover with respect to the track is detected as a function of the high frequency voltage,
a location of the at least one magnet on each mover with respect to the track is determined, and
whether the at least one magnet is mounted at the first distance or the second distance for each mover is determined as a function of the position of the at least one drive magnet and the location of the at least one magnet on the corresponding mover.

5. The system of claim 1 further comprising at least one additional magnet mounted to the first mover, wherein each of the plurality of sensors generates the first signal corresponding to the magnetic field generated by a combination of the first magnet and the at least one additional magnet.

6. The system of claim 1 wherein at least two sensors, selected from the plurality of sensors, are operative in tandem to generate either the first signal or the second signal, the system further comprising:
a controller configured to receive a feedback signal from each of the at least two sensors to generate the first signal or the second signal and to identify the first mover as a function of either a relative strength or an angle of each feedback signal received from the at least two sensors for each position magnet.

7. The system of claim 1 wherein:
the first magnet includes a first shape, a first magnetic field strength, and a first orientation to generate a first magnetic field,
each of the other magnets includes a second shape, a second magnetic field strength, and a second orientation to generate a second magnetic field, and
at least one of the first shape and the second shape, the first magnetic field strength and the second magnetic field strength, or the first orientation and the second orientation is different, such that the first magnetic field is different than the second magnetic field.

8. The system of claim 1 wherein:
the first magnet is mounted to the first mover with a first polarity,
each of the other magnets in the plurality of magnets is mounted to one of the other movers with a second polarity, and
the first polarity is different than the second polarity.

9. The system of claim 8 , wherein the first magnet and each of the other magnets in the plurality of magnets is a position magnet mounted on the corresponding mover.

10. The system of claim 8 , wherein the first magnet and each of the other magnets is one of a plurality of drive magnets mounted on the corresponding mover.

11. A method for identifying a first mover, selected from a plurality of movers, wherein each of the plurality of movers travels along a track, the method comprising the steps of:
receiving a plurality of position signals at a controller, wherein:
each position signal is generated by one of a plurality of sensors spaced apart along the track,
each position signal corresponds to at least one magnet mounted to one mover of the plurality of movers, and
each position signal is either a first signal or a second signal, the first signal having a different waveform than the second signal;

comparing each of the plurality of position signals to each other in the controller;
identifying in the controller a first mover, selected from the plurality of movers, corresponding to the first signal.

12. The method of claim 11 wherein at least two sensors, selected from the plurality of sensors, generates the position signal corresponding to the at least one magnet mounted to one of the plurality of movers.

13. The method of claim 11 wherein:
the at least one magnet of the first mover includes a first shape, a first magnetic field strength, and a first orientation to generate a first magnetic field,
the at least one magnet of each of the movers includes a second shape, a second magnetic field strength, and a second orientation to generate a second magnetic field, and
at least one of the first shape and the second shape, the first magnetic field strength and the second magnetic field strength, or the first orientation and the second orientation is different.

14. The method of claim 11 wherein:
a first magnet is mounted to the first mover with a first polarity to generate the first signal,
each of the other magnets is mounted to one of the other plurality of movers with a second polarity to generate the second signal, wherein the first polarity is different than the second polarity.

15. The method of claim 14 , wherein the first magnet and each of the other magnets is a position magnet mounted on the corresponding mover.

16. The method of claim 14 , wherein the first magnet and each of the other magnets is one of a plurality of drive magnets mounted on the corresponding mover.

17. A system for identifying a first mover, selected from a plurality of movers, wherein each of the plurality of movers travels along a track, the system comprising:
a plurality of magnets, wherein at least one magnet is mounted to each of the plurality of movers and generates a magnetic field; and
a plurality of sensors spaced apart along the track, wherein:
each of the plurality of sensors generates a signal corresponding to the magnetic field generated by the at least one magnet mounted to a mover as the mover passes the sensor,
a first magnet mounted to the first mover has a first polarity,
each of the magnets mo

Assignees

• Rockwell Automation Tech Inc

Inventors

• Ozimek Patrick E
• Haya Oliver C
• Smit Peter M
• Koeppel Marc

Classifications

• B65G43/10 Primary

  Sequence control of conveyors operating in combination · CPC title

• H02K41/031 Primary

  of the permanent magnet type · CPC title

• H02K11/21

  Devices for sensing speed or position, or actuated thereby (specially adapted for machines having non-mechanical commutating devices H02K29/06, H02K29/14) · CPC title

• B65G54/02

  electrostatic, electric, or magnetic · CPC title

• G11B27/321

  used signal consists of two 180-degr. phase shifted signals of the same frequency · CPC title