Inductive sensor for a position measuring system, method of manufacturing inductive sensor, and position measuring system provided with inductive sensor

Patent metadata

Field	Value
Publication number	US-9605980-B2
Application number	US-3755408-A
Country	US
Kind code	B2
Filing date	Feb 26, 2008
Priority date	Mar 1, 2007
Publication date	Mar 28, 2017
Grant date	Mar 28, 2017

Abstract

An inductive sensor has an electrically nonconductive substrate, at least one electrically conducting coil that is integrally joined to the substrate, with the mechanical rigidity of the substrate significantly greater than that of the conducting coil, a metal plate covering the conducting coil, with the substrate comprised by the metal plate, and with the surface of the metal plate on the side oriented toward the conducting coil provided with an electrically insulating layer.

First claim

What is claimed as new and desired to be protected by Letters Patent is set forth in the appended claims:

1. A position measuring system, comprising:
a sheet metal strip composed of magnetizable sheet metal and having a multitude of periodically situated rectangular cutouts; and
an inductive sensor with a housing forming a passage with a first opening at one end of the passage and a second opening at another end of the passage, at least one electrically conducting coil and a flexible circuit board connected to the at least one electrically conducting coil at one end and having another end for connecting to evaluation electronics;
wherein the first opening is closed by a steel metal plate formed with an interior surface that faces an interior of the housing and an outer surface that opposes the interior surface and that faces away from the interior of the housing;
wherein an insulation layer is integrally joined to the interior surface of the steel metal plate that faces the interior of the housing;
wherein the at least one electrically conducting coil is positioned on and integrally joined to a surface of the insulation layer that faces away from the metal plate to the interior of the housing;
wherein the insulation layer separates the at least one electrically conductive coil from the interior surface of the steel metal plate;
wherein the steel metal plate both covers the at least one electrically conducting coil and functions as a substrate to provide stability for the at least one conducting coil;
wherein the outer surface of the steel metal plate faces the sheet metal strip; and
wherein a distance between the at least one electrically conducting coil and the sheet metal strip is smaller than a period of the multitude of periodically situated rectangular cutouts.

2. The position measuring system as defined in claim 1 , wherein said insulating layer is thinner than 10 mm.

3. The position measuring system as defined in claim 1 , wherein said at least one conducting coil is a flat spiral.

4. The position measuring system as defined in claim 3 , wherein said flat spiral has at least 10 loops.

5. The position measuring system as defined in claim 1 , wherein said insulating layer is composed of polyimide.

6. The position measuring system as defined in claim 1 , wherein said insulating layer is configured as a layer manufactured with a centrifuge method.

7. The position measuring system as defined in claim 1 , wherein said steel metal plate is a plate welded to said housing with a welding seam that does not protrude above a plane defined by the outer surface of said metal plate.

8. The position measuring system as defined in claim 7 , wherein said steel metal plate is a flat metal plate.

9. The position measuring system as defined in claim 1 , wherein a casting material is poured into the second opening of said housing.

10. The position measuring system as defined in claim 1 , wherein the flexible printed circuit board is provided with a contacting section and a connecting section, said contacting section being completely covered by a casting compound and said connecting section protrudes out from said casting compound.

11. The position measuring system as defined in claim 10 , further comprising a dividing layer provided between said contacting section and said steel metal plate and being at least five times thicker than said metal plate.

12. The inductive sensor as defined in claim 1 , wherein the steel metal plate is fastened directly to the housing.

Assignees

• Reusing Guenter
• Hollweck Roman
• Hauser Karin
• Stier Anton
• Hohnke Florian
• Bosch Gmbh Robert

Inventors

• Reusing Guenter
• Hollweck Roman
• Hauser Karin
• Stier Anton
• Hohnke Florian

Classifications

• Y10T29/4902

  Electromagnet, transformer or inductor · CPC title

• G01B7/023

  for measuring distance between sensor and object (G01B7/082 and G01B7/102 take precedence) · CPC title

• G01D5/2006 Primary

  by influencing the self-induction of one or more coils (G01D5/22 takes precedence) · CPC title

• F16C29/00

  Bearings for parts moving only linearly (F16C32/06 takes precedence; incorporated in flexible shafts F16C1/28 {; parts of bearings in general and special methods for making bearings or parts thereof in general F16C33/00}) · CPC title

• G01B7/14

  for measuring distance or clearance between spaced objects or spaced apertures (G01B7/30 takes precedence) · CPC title