Mechanical component having a cylindrical nanotube force sensor

• US 10,035,399 B2
• Filed: 10/19/2015
• Issued: 07/31/2018
• Est. Priority Date: 11/20/2014
• Status: Active Grant

• Current Assignee: ZF Friedrichshafen AG (Zeppelin - Stiftung der Stadt Friedrichshafen)
• Original Assignee: ZF Friedrichshafen AG (Zeppelin - Stiftung der Stadt Friedrichshafen)
• Inventors: Haskamp, Klaus, Klank, Michael, Hofmann, Peter
• Primary Examiner(s): Noori, Max
• Application Number:
  US15/527,782
• Publication Number:
  US 20170320369A1
• Time in Patent Office: 1,016 Days
• Field of Search: 7386268
• CPC Class Codes: B60G 17/019 characterised by the type of sensor or the arrangement thereof B60G17/01941 takes precedence
• CPC Class Codes: B60G 2204/1162 directly mounted on the suspension arm
• CPC Class Codes: B60G 2204/416 Ball or spherical joints
• CPC Class Codes: B60G 7/005 Ball joints B60G7/006 takes precedence; for steering linkage B62D7/16; ball joints per se F16C11/06
• CPC Class Codes: F16C 11/0604 Construction of the male part
• CPC Class Codes: F16C 11/0619 the female part comprising a blind socket receiving the male part
• CPC Class Codes: F16C 2233/00 Monitoring condition, e.g. temperature, load, vibration
• CPC Class Codes: F16C 41/007 Encoders, e.g. parts with a plurality of alternating magnetic poles
• CPC Class Codes: G01L 1/18 using properties of piezo-resistive materials, i.e. materials of which the ohmic resistance varies according to changes in magnitude or direction of force applied to the material
• CPC Class Codes: G01L 1/2293 of the semi-conductor type semi-conductor devices controllable by variations of applied mechanical force H01L29/84

Abstract

A mechanical component for a vehicle, such as a ball stud, having a cylindrical measurement region with an outer surface. A force sensor is associated with the cylindrical measurement region for detecting at least one force to which the component is exposed. The forces detected by the nanotube sensor may include compressive and/or tensile stress forces. The force sensor includes a layer of carbon nanotubes applied to the outer surface of the cylindrical measurement region.

Claims

1. A mechanical component for a vehicle comprising:

a cylindrical measurement region of a ball stud (3) having an outer surface,

a force sensor associated with the cylindrical measurement region for detecting at least one force to which the mechanical component is exposed,

the force sensor comprising a layer (5) of carbon nanotubes, and

the layer (5) of carbon nanotubes being applied to the outer surface of the cylindrical measurement region (x).

2. The mechanical component according to claim 1, wherein an insulating layer (4) is disposed between the layer (5) of carbon nanotubes and the outer surface of the cylindrical measurement region (x) of the mechanical component (3b).

3. The mechanical component according to claim 1, wherein the layer (5) of carbon nanotubes forms an electrically conductive connection and has at least one input contact (6) and at least one output contact (7).

4. The mechanical component according to claim 3, wherein the input and the output contacts (6, 7) are connected, by electrical conductors (6a, 7a), to evaluation electronics (8) and a power source.

5. The mechanical component according to claim 1, wherein the layer (5) of carbon nanotubes is formed as a varnish layer which adheres to the outer surface of the cylindrical measurement region (x) of the mechanical component (3b).

6. The mechanical component according to claim 1, wherein either the layer (5) of carbon nanotubes or a varnish layer, that forms the layer (5) of carbon nanotubes, is applied to the shaft (3b) of the ball stud (3).

8. The mechanical component for a vehicle according to claim 1, wherein the at least one force comprises compressive and/or tensile stress.

10. The mechanical component for a vehicle according to claim 4, wherein the power source produces a constant current through the layer of carbon nanotubes.

7. A mechanical component for a vehicle comprising:

a cylindrical measurement region of a shaft of a ball stud (3b),

the cylindrical measurement region of the shaft of the ball stud having an outer surface,

a force sensor being associated with the cylindrical measurement region for determining stress forces to which the shaft of the ball stud is exposed,

the force sensor comprising a layer of carbon nanotubes,

the layer of the carbon nanotubes being coated on the outer surface of the cylindrical measurement region of the shaft of the ball stud,

the layer of carbon nanotubes being electrically conductive and having an electrical resistance that changes based on mechanical stress placed on the carbon nanotubes,

the layer of the carbon nanotubes having an input contact and an output contact, and

the input and the output contacts being connected, via electrical conductors, to evaluation electronics and evaluate voltage signals are transmitted between the evaluation electronics and the layer of the carbon nanotubes for determining a stress force to which the shaft of the ball stud is exposed.

9. The mechanical component for a vehicle according to claim 7, wherein the stress forces comprise compressive and/or tensile stress forces.

11. The mechanical component for a vehicle according to claim 7, further comprising a power source that produces a constant current through the layer of nanotubes.