Method and apparatus for classifying and recovering the main components of used batteries

• US 6,337,450 B1
• Filed: 12/08/1999
• Issued: 01/08/2002
• Est. Priority Date: 12/08/1998
• Status: Expired due to Fees

• Current Assignee: Mitsubishi Heavy Industries, Ltd.
• Original Assignee: Mitsubishi Heavy Industries, Ltd.
• Inventors: Honnmura, Shiro, Hirai, Takahiko, Miyauchi, Reizou, Kurokawa, Masaaki, Tsuzuki, Satoshi, Tanii, Tadaaki, Kamimura, Takeo
• Primary Examiner(s): Walsh, Donald P.
• Assistant Examiner(s): Rodriguez, Joseph C.
• Application Number:
  US09/456,562
• Time in Patent Office: 762 Days
• Field of Search: 209/571, 209/573, 209/575, 198/391, 198/392, 198/443, 324/426
• US Class Current: 209/575
• CPC Class Codes: B07C 5/344 according to electric or electromagnetic properties sorting according to size measured electrically or electronically B07C5/08; material testing by magnetic means G01N24/00, G01N27/00, by electrical means G01N27/00; electrical measuring devices in general G01R; coin testing G07D5/00
• CPC Class Codes: B07C 5/365 using a single separation means
• CPC Class Codes: H01M 10/54 Reclaiming serviceable parts of waste accumulators
• CPC Class Codes: H01M 6/52 Reclaiming serviceable parts of waste cells or batteries , e.g. recycling
• CPC Class Codes: Y02W 30/84 Recycling of batteries or fuel cells

Abstract

A method and an apparatus for classifying and recovering the main components of used batteries, particularly, a method and an apparatus by which the batteries are conveyed on a conveyor while an alternating magnetic field of a plurality of frequencies is applied to each and a detection means detects what sort of induced magnetic field has resulted from the eddy current induced in the battery. The orthogonal components in the change of the induced magnetic field are detected; the relationship between these orthogonal components and the frequencies are compared with the database of the same which is previously obtained, and the batteries are sorted according to their classification and size. This method can sort large amounts of used batteries continuously. In this invention, the battery will be drawn down into the detection region either magnetically or mechanically while the stable transport of the battery is achieved. The method and apparatus of the invention enable continuous bulk sorting of batteries, assure a smooth feed, and improve the accuracy with which the induced magnetic field generated in the battery is detected.

Claims

1. A method of sorting batteries, comprising:

continuously conveying a plurality of kinds of batteries;

successively aligning the batteries to be sorted;

successively applying a weak non-saturating magnetostatic field of between 0.01 T (Teslas) and 0.3 T and at least an alternating magnetic field having a plurality of different frequencies to the batteries to be sorted in order to induce an eddy current in each of the batteries;

detecting an induced magnetic field created by the eddy current induced in said each of the batteries in order to measure strength and phase-shift of the detected induced magnetic field with respect to the plurality of different frequencies; and

determining a classification and size of said each of the batteries based on a previously obtained relationship of battery classification and size relative to the measured strength and phase-shift of the induced magnetic field generated by the plurality of different frequencies.

2. A method of sorting batteries according to claim 1, wherein said weak magnetostatic field is between 0.01 T and 0.07 T when the kinds of batteries are size AA or smaller.

3. A method of sorting batteries according to claim 1, wherein the previously obtained relationship has a plurality of predetermined tolerance ranges of magnetic field strength and phase-shift for each frequency, and said determining step determines the classification and size of said each of the batteries by a combination of the tolerance ranges at the different frequencies.

4. A method of sorting batteries according to claim 1, wherein:

the plurality of different frequencies is selected from each of high, intermediate, and low frequency ranges;

the induced alternating magnetic field is analyzed at each of the plurality of different frequencies into orthogonal components which are a respective sine component and a respective cosine component; and

a logical operation of “

AND” and

“

OR”

is executed to determine whether or not the respective sine component and cosine component belong to a zone defined by sine components and cosine components determined beforehand for the battery classification and size of each of the batteries for said each of the plurality of different frequencies to sort out the classification and size of the battery to be sorted.

5. A method of sorting batteries, comprising:

continuously conveying a plurality of kinds of batteries;

successively aligning the batteries to be sorted;

successively applying an alternating magnetic field having a plurality of different frequencies to the batteries to be sorted in order to induce an eddy current in each of the batteries;

detecting an induced magnetic field created by the eddy current induced in said each of the batteries in order to measure strength and phase-shift of the induced magnetic field with respect to the plurality of different frequencies; and

determining a classification and size of said each of the batteries based on a previously obtained relationship of battery classification and size relative to the measured strength and phase-shift of the induced magnetic field generated by the plurality of different frequencies, wherein the previously obtained relationship has a plurality of predetermined tolerance ranges of magnetic field strength and phase-shift for each frequency, and said determining step determines the classification and size of said each of the batteries by a combination of the tolerance ranges at the different frequencies.

6. A method of sorting batteries according to claim 5, wherein:

the plurality of different frequencies is selected from each of high, intermediate, and low frequency ranges;

the induced alternating magnetic field is analyzed at each of the plurality of different frequencies into orthogonal components which are a respective since component and a respective cosine component; and

a logical operation of “

AND” and

“

OR”

is executed to determine whether or not the respective sine component and cosine component belong to a zone defined by sine components and cosine components determined beforehand for the battery classification and size of each of the batteries for said each of the plurality of different frequencies to sort out the classification and size of the battery to be sorted.

7. A sorting apparatus for sorting a continuously conveyed succession of batteries, said apparatus comprising:

an arranging and conveying device which arranges and continuously conveys the batteries at regular intervals, said device comprising a rotary-type conveyor and a line-type conveyor, said rotary-type conveyor having an obliquely oriented first disk rotating on a first axis, and a horizontal second disk surrounding the first disk and rotating on a second axis, said first and second axes being position to intersect each other, the second disk being rotating faster than the first disk;

the batteries being forwarded in the rotary-type conveyor and arranged by centrifugal force;

the line-type conveyor conveying the arranged batteries from the rotary-type conveyor at regular intervals;

an alternating magnetic field generator which applies an alternating magnetic field successively to each of the batteries;

a weak magnetostatic field generator which applies a weak non-saturating magnetostatic field of between 0.01 T and 0.3 T to the batteries passing by a position where an attitude of each of the batteries is stabilized on the conveyor belt;

an induced magnetic field detector which successively detects magnetic field strength and phase changes of an induced magnetic field in the batteries for at least 3 different frequencies;

a signal processor which determines a classification and size of each battery by applying “

AND” and

“

OR”

logical operations to the detected magnetic field strength and phase changes of the induced magnetic field, and outputs a sorting output signal for each battery; and

a sorter which sorts the batteries to specific locations according to the sorting output signals.

8. A sorting apparatus for sorting batteries according to claim 7, further comprising a weak magnetostatic field generator which applies a weak magnetostatic field successively to each of the batteries.

9. A sorting apparatus for sorting batteries according to claim 8, wherein said line-type conveyor is tilted along an axis of its width in order to line up and convey the batteries so as to stabilize the position of each battery as the battery passes said weak magnetostatic field generator and said alternating magnetic field generator.

10. A sorting apparatus for sorting batteries according to claim 7, wherein said alternating magnetic field generator is provided with a plurality of generating coils to generate an alternating magnetic field, and said induced magnetic field detector is provided with a plurality of detecting coils to detect the strength and phase changes of the induced magnetic field, wherein the generating coils and the detecting coils are both local acting coils, and wherein both said generating coils and said detecting coils each comprise a large type coil and a small type coil for respectively detecting the composition of large and small batteries.

11. A sorting apparatus for sorting batteries, comprising:

a transporter in which batteries are introduced onto a disk rotating at high speed to be disposed and oriented on a periphery of the disk by centrifugal force acting on the batteries while revolving on the disk;

a conveyor belt for conveying the oriented batteries;

a weak non-saturating magnetostatic field generator which applies a weak magnetostatic field of between 0.01 T and 0.3 T to the batteries passing by a position where an attitude of each of the batteries is stabilized on the conveyor belt; and

an alternating magnetic fields generator which applies a plurality of alternating magnetic fields at frequencies selected from each of high, intermediate, and low frequency ranges to the batteries at the position where the attitude of each of the batteries is stabilized on the conveyor belt.

12. A sorting apparatus for sorting batteries according to claim 11, further comprising:

an analyzer for analyzing induced alternating magnetic fields from application of the alternating magnetic fields into a sine component and a cosine component at each of the frequencies; and

a determiner for determining whether or not the sine component and the cosine component at each of the frequencies belong to a zone defined by sine components and cosine components determined beforehand for each classification and size of batteries for each of the frequencies to sort out the classification and size of the batteries.

13. A sorting apparatus for sorting batteries according to claim 11, wherein:

the conveyor belt is tilted along an axis of width in order to line up and convey the batteries so as to stabilize the position of each of the batteries passing thereby on a lower side position of inclination of the conveyor belt; and

the weak magnetostatic field generator and the alternating magnetic fields generator are provided at the lower side position of inclination of the conveyor belt.