Composite material for temperature measurement, temperature sensor comprising the composite material, and method for producing the composite material and the temperature sensor

• US 9,341,521 B2
• Filed: 02/09/2009
• Issued: 05/17/2016
• Est. Priority Date: 02/19/2008
• Status: Active Grant

• Current Assignee: TDK Electronics AG (TDK Corporation)
• Original Assignee: Epcos AG (TDK Corporation)
• Inventors: Kloiber, Gerald, Strallhofer, Heinz
• Primary Examiner(s): KAPLAN VERBITSKY, GAIL
• Application Number:
  US12/918,286
• Publication Number:
  US 20110051778A1
• Time in Patent Office: 2,654 Days
• Field of Search: 374/185, 374/178, 374/163, 374/100, 374/179, 338/22.R, 338/25, 338/28
• US Class Current: 1/1
• CPC Class Codes: G01K 7/223 characterised by the shape of the resistive element
• CPC Class Codes: H01C 7/02 having positive temperature coefficient ceramics C04B
• CPC Class Codes: H01C 7/04 having negative temperature coefficient thermometers using resistive elements G01K7/16
• CPC Class Codes: H01C 7/045 Perovskites, e.g. titanates
• CPC Class Codes: Y10T 29/49002 Electrical device making

Abstract

A composite material 1 for temperature measurement is specified, as is a temperature sensor 10 formed from the composite material 1. Additionally specified are processes for producing the composite material 1 and for producing the temperature sensor 10.

Claims

1. A temperature sensor comprising a composite material for temperature measurement, wherein the composite material comprises:

a pulverulent ceramic filler comprising an electrically conductive spinel of the formula A^IIB^III₂O₄ or perovskite of the formula ABO₃ where A and B are each metals; and

a formable matrix which embeds the filler, wherein the matrix comprises a material selected from a group consisting of glass-like materials, thermoplastic thermosets, elastomers, and mixtures thereof;

wherein the ceramic filler has a positive or negative temperature coefficient of electrical resistance, and the composite material has a resistance-temperature characteristic determined by the ceramic filler,

wherein the temperature sensor is in the form of a film, and

wherein the film is flexible.

2. The temperature sensor as claimed in claim 1, wherein the filler is present as a multitude of particles in the matrix.

3. The temperature sensor as claimed in claim 2, wherein the particles have a filling level in the matrix of 50% to 95%.

4. The temperature sensor as claimed in claim 2, wherein the particles form continuous current paths in the matrix.

5. The temperature sensor as claimed in claim 1 having contacts.

6. The temperature sensor as claimed in claim 5, wherein the contacts are applied on the surface of the temperature sensor and/or integrated into the temperature sensor.

7. A process for producing the temperature sensor claimed in claim 1 and having contacts, comprising the steps of:

A. producing the composite material by a process comprising the steps of;

i. producing the ceramic filler,

ii. providing the matrix, and

iii. mixing the filler and the matrix;

B. forming the composite material; and

C. applying the contacts.

8. A temperature sensor comprising a composite material for temperature measurement, the composite material comprising:

a pulverulent ceramic filler comprising an electrically conductive spinel of the formula A^IIB^III₂O₄ or perovskite of the formula ABO₃ where A and B are each metals; and

a formable matrix which embeds the filler, wherein the matrix comprises a material selected from a group consisting of glass-like materials, thermoplastics, thermosets, elastomers, and mixtures thereof;

wherein the ceramic filler has a positive or negative temperature coefficient of electrical resistance, and the composite material has a resistance-temperature characteristic determined by the ceramic filler,

wherein the filler is present as a multitude of particles in the matrix, and

wherein the particles have a filling level in the matrix of 50% to 95%

wherein the temperature sensor is in the form of a film, and

wherein the film is flexible.

9. A process for producing a temperature sensor as claimed in claim 8, comprising the process steps of:

A) producing the ceramic filler;

B) providing the matrix; and

C) mixing the filler and the matrix.

10. The temperature sensor as claimed in claim 8 and having contacts.

11. A process for producing the temperature sensor claimed in claim 8 and having contacts, comprising the steps of:

A. producing the composite material by a process comprising the steps of;

i. producing the ceramic filler,

ii. providing the matrix, and

iii. mixing the filler and the matrix;

B. forming the composite material; and

C. applying the contacts.