Thin magnet fabrication

Patent metadata

Field	Value
Publication number	US-2016358703-A1
Application number	US-201514733844-A
Country	US
Kind code	A1
Filing date	Jun 8, 2015
Priority date	Jun 8, 2015
Publication date	Dec 8, 2016
Grant date	—

Abstract

This application relates to manufacturing techniques for producing thin magnetic elements. In particular, the manufacturing processes are designed to accommodate the mechanical properties of sintered magnetic substrates. One of the manufacturing processes involves cutting a magnetizable substrate into a number of slices and adhesively coupling the slices to a sheet that can take the form of a layer of grinding tape. After concurrently grinding a first surface of each of the slices, the slices are flipped over so that the first surface of each slice is attached to another layer of grinding tape. A second surface of each of the slices is then ground until a desired thickness is achieved. Subsequent to the grinding, dicing operations can be applied to the slices to produce magnets having a desired length and width.

First claim

What is claimed is:

1 . A manufacturing method, comprising:
cutting a substrate formed of magnetizable material into slices having an initial thickness greater than a desired thickness; removing portions of the slices until the desired thickness of the slices is achieved; singulating each of the slices into a number of magnetic elements while the slices are coupled with a support structure; and magnetizing the magnetic elements in accordance with a desired magnetic property prior to removing the magnetic elements from the support structure.

2 . The manufacturing method as recited in claim 1 , wherein the magnetic elements are adhesively coupled to the support structure.

3 . The manufacturing method as recited in claim 2 , wherein magnetizing the magnetic elements comprises applying sequential magnetizing operations to the magnetic elements to achieve the desired magnetic property in which at least two of the magnetic elements emit magnetic fields oriented in opposite directions.

4 . The manufacturing method as recited in claim 2 , further comprising:
magnetically coupling a ferrous substrate with each of the magnetic elements by placing the ferrous substrate in direct contact with a surface of the support structure opposite the magnetic elements.

5 . The manufacturing method as recited in claim 2 , wherein the support structure comprises a layer of UV-curable adhesive to affix a surface of each slice to the support structure, and wherein UV irradiation of the UV-curable adhesive substantially reduces a strength of an adhesive bond between the magnetized magnetic elements and the support structure.

6 . The manufacturing method as recited in claim 1 , wherein removing portions of the slices comprises concurrently applying a grinding operation to an exposed surface of each slice until each of the slices are substantially the same thickness.

7 . The manufacturing method as recited in claim 1 , wherein singulating each of the slices comprises applying a number of sawing operations in a first direction and a number of sawing operations in a second direction orthogonal to the first direction.

8 . The manufacturing method as recited in claim 1 , wherein the desired thickness is less than 100 microns.

9 . The manufacturing method as recited in claim 1 , wherein the magnetizable material is a neodymium alloy.

10 . A method, comprising:
cutting a magnetizable substrate into a number of slices; grinding a first side of each of the slices; coupling the first side of each of the slices to a support structure; concurrently grinding a second side of each of the slices until a desired thickness of each of the slices is achieved, the second side being opposite the first side; dicing each of the slices into a number of magnetic elements having a desired length and width; plating exposed surfaces of each of the magnetic elements with an anti-corrosive layer; magnetizing the magnetic elements; and coupling a magnetically attractable plate to a surface of the support structure opposite the magnetic elements to keep the magnetic elements fixed in place on the support structure.

11 . The method as recited in claim 10 , further comprising:
removing the magnetic elements from the support structure and installing the magnetic elements on a printed circuit board (PCB) so that an exposed surface of each of the magnetic elements is coupled with a surface of the PCB.

12 . The method as recited in claim 10 , wherein dicing the slices comprises using a linear cutting tool to cut each of the slices into magnetic elements having substantially the same length and width.

13 . The method as recited in claim 12 , wherein the linear cutting tool is a diamond saw.

14 . The method as recited in claim 10 , wherein the support structure is a first adhesive sheet and wherein the method further comprises prior to grinding the first side of each of the slices, adhesively coupling the second side of each of the slices to a second adhesive sheet.

15 . The method as recited in claim 14 , further comprising:
irradiating the second adhesive sheet to reduce the adhesive coupling between the second side of each of the slices and the second adhesive sheet; and separating each of the slices from the second adhesive sheet.

16 . A non-transitory computer readable storage medium configured to store instructions that, when executed by a processor in a computer numerical control (CNC) device, cause the CNC device to carry out a manufacturing method, by carrying out steps that include:
cutting a magnetizable substrate into a number of slices having substantially similar geometries; adhesively coupling a first surface of each of the slices to a first adhesive sheet; grinding a second surface of each of the slices, the second surface being positioned opposite the first surface, until a desired surface finish is achieved on the second surface; adhesively coupling the second surface of each slice to a second adhesive sheet; separating the first surface of each of the slices from the first adhesive sheet; grinding the first surface of each of the slices until a desired thickness of each of the slices is reached; and dicing each of the slices into a number of magnetic elements.

17 . The non-transitory computer readable storage medium as recited in claim 16 , wherein separating the first surface of each slice from the first adhesive sheet comprises irradiating the first adhesive sheet with ultraviolet (UV) light to reduce a strength of the adhesive coupling between the first surface and the first adhesive sheet.

18 . The non-transitory computer readable storage medium as recited in claim 16 , wherein the desired thickness of the slices is less than 150 microns.

19 . The non-transitory computer readable storage medium as recited in claim 16 , wherein the steps further include magnetizing the magnetic elements while the magnetic elements are still attached to the second adhesive sheet.

20 . The non-transitory computer readable storage medium as recited in claim 16 , wherein the steps further include plating the magnetic elements before the magnetic elements are removed from the second adhesive sheet.

Assignees

• Apple Inc

Inventors

• Kriman Moshe
• Magen Adar

Classifications

• H01F7/02 Primary

  Permanent magnets {[PM]} · CPC title

• Y10T156/1917

  Electromagnetic radiation delaminating means [e.g., microwave, uv, ir, etc.] · CPC title

• Y10T29/49078

  Laminated · CPC title

• Y10T29/49075

  including permanent magnet or core · CPC title

• H02K15/03

  having permanent magnets · CPC title