Level with magnetic coupling

Patent metadata

Field	Value
Publication number	US-10317209-B2
Application number	US-201615271045-A
Country	US
Kind code	B2
Filing date	Sep 20, 2016
Priority date	Sep 21, 2015
Publication date	Jun 11, 2019
Grant date	Jun 11, 2019

Abstract

A tool, such as a level, including one or more magnetic coupling device is provided. The magnetic coupling device may be a magnetic circuit including metal components surrounding a magnet, such as a permanent rare-earth magnet.

First claim

What is claimed is:

1. A level comprising:
a level body formed from a first metallic material, the level body defining a base surface configured to engage a workpiece;
at least one level vial located within the level body;
a cavity located in the level body defining an opening along the base surface;
a magnetic circuit coupled to the level body within the cavity, the magnetic circuit comprising:
a pair of metallic structures, formed from a second metallic material, wherein the second metallic material is a ferromagnetic material and is different from the first metallic material; and
a permanent magnet located between opposing inner surfaces of the pair of metallic structures;

wherein each of the opposing inner surfaces of the metallic structures is a non-vertical, non-planar surface, and the permanent magnet includes a pair of non-vertical, non-planar lateral surfaces each facing the opposing inner surfaces of the metallic structures, wherein the non-vertical, non-planar shape of the lateral surfaces of the permanent magnet engages the opposing non-vertical, non-planar surfaces of the metallic structures such that relative movement between the permanent magnet and the metallic structures is resisted.

2. The level of claim 1 , wherein the first metallic material has a first magnetic reluctance and the second metallic material has second magnetic reluctance, wherein the second magnetic reluctance is less than the first magnetic reluctance.

3. The level of claim 1 , wherein the permanent magnet defines a north-south axis oriented in a direction extending between the opposing inner surfaces of the pair of metallic structures.

4. The level of claim 3 , wherein the base surface defines a plane, wherein the north-south axis of the magnet is substantially parallel to the plane of the base surface.

5. The level of claim 4 , wherein the base surface defines a longitudinal axis extending between front and rear ends of the level body, wherein the north-south axis of the magnet is substantially perpendicular to the longitudinal axis of the level body.

6. The level of claim 1 , wherein the level body defines a longitudinal axis extending between front and rear ends of the level body, wherein the pair of metallic structures combined has a first width perpendicular to the longitudinal axis and the permanent magnet has a second width perpendicular to the longitudinal axis, wherein the first width is greater than the second width.

7. The level of claim 6 , wherein the first width is a maximum width of the pair of metallic structures in the direction perpendicular to the longitudinal axis, wherein the second width is a maximum width of the permanent magnet in the direction perpendicular to the longitudinal axis.

8. The level of claim 1 , wherein a maximum height of each of the metallic structures is less than a depth of the cavity such that an outermost horizontal surface of each of the metallic structures is recessed below the base surface.

9. The level of claim 8 , wherein a maximum height of the permanent magnet is less than the maximum height of each of the metallic structures such that the permanent magnet is recessed below the outermost horizontal surfaces of the metallic structures.

10. The level of claim 1 , further comprising a groove formed in the base surface and extending in a longitudinal direction along an entire longitudinal length of the base surface, wherein the cavity is located within the groove, wherein each of the metallic structures includes an angled outer surface defining a plane located at an angle relative to the base surface between 0 degrees and 90 degrees, the angled outer surface facing in a direction away from the base surface and away from the permanent magnet.

11. The level of claim 1 , wherein the magnetic circuit generates a magnetic coupling force of at least 8 lbs., wherein the permanent magnet is a rare earth magnet and has a volume between 0.005 inches 3 and 0.3 inches 3 .

12. The level of claim 1 , wherein the permanent magnet defines a north-south axis and the level body defines a width axis, wherein the permanent magnet is positioned relative to the level body such that an angle between the north-south axis and the width axis is between 0 degrees and 45 degrees.

13. The level of claim 1 , wherein the permanent magnet has a first Rockwell hardness and the metallic structures have a second Rockwell hardness, wherein the second Rockwell hardness is greater than the first Rockwell hardness.

14. A tool comprising:
a tool body formed from a first material and having a first surface;
a magnetic coupling element supported by the tool body such that a magnetic field generated by the magnetic coupling element extends outward from the first surface, the magnetic coupling element comprising:
a permanent magnet; and
a metallic sleeve structure at least partially surrounding the permanent magnet, wherein the metallic sleeve structure is formed from a magnetic material that is different from the first material and has a magnetic reluctance that is less than a magnetic reluctance of the first material,

wherein the metallic sleeve structure comprises an inner surface facing an outer surface of the permanent magnet, wherein the inner surface of the metallic sleeve structure is a non-vertical, non-planar surface, and the outer surface of the permanent magnet is a non-vertical, non-planar surface facing the inner surface of the metallic sleeve structure, wherein the non-vertical, non-planar shape of the outer surface of the permanent magnet engages the non-vertical, non-planar inner surface of the metallic sleeve structure such that relative movement between the permanent magnet and the metallic sleeve structure is resisted.

15. The tool of claim 14 , wherein both the permanent magnet and the metallic sleeve structure are recessed relative to the first surface.

16. The tool of claim 15 , wherein the tool body is a level body and further comprising:
at least one level vial located within the tool body, wherein the first surface is a planar base surface configured to engage a workpiece; and
a cavity formed in the level body, wherein the magnetic coupling element is located in and coupled to the level body within the cavity.

Assignees

• Milwaukee Electric Tool Corp

Inventors

• Lasota Richard J
• Schultz Timothy Allen
• Boehme Christopher Frederick
• Resnick Adam Christopher

Classifications

• G01C9/28 Primary

  Mountings · CPC title