Vibration and dynamic acceleration sensing using capacitors

Patent metadata

Field	Value
Publication number	US-10240991-B2
Application number	US-201715785189-A
Country	US
Kind code	B2
Filing date	Oct 16, 2017
Priority date	Aug 26, 2013
Publication date	Mar 26, 2019
Grant date	Mar 26, 2019

Abstract

The present disclosure relates to an apparatus comprising at least one sensing capacitor and a controller, wherein the controller is configured to receive a signal from the at least one sensing capacitor indicative of a change of charge of the sensing capacitor, and wherein the controller is configured to determine an amount of force applied to the sensing capacitor, an acceleration of the sensing capacitor, a torsion of the sensing capacitor, a vibration of the sensing capacitor or a pulling force applied to the sensing capacitor based on the change of charge of the at least one sensing capacitor.

First claim

The invention claimed is:

1. Apparatus comprising:
at least one sensing capacitor, and
a controller, wherein
the controller is configured to receive a signal from the at least one sensing capacitor indicative of a change of charge of the sensing capacitor, and wherein the controller is configured to determine an amount of force applied to the sensing capacitor, an acceleration of the sensing capacitor, a torsion of the sensing capacitor, a vibration of the sensing capacitor or a pulling force applied to the sensing capacitor based on the change of charge of the at least one sensing capacitor.

2. Apparatus according to claim 1 , further comprising
a charge amplifier connected between the at least one sensing capacitor and the controller.

3. Apparatus according to claim 2 , characterized in that
the charge amplifier comprises at least a first operational amplifier.

4. Apparatus according to claim 3 , further comprising
at least one first capacitor is connected between the output of the operational amplifier and the inverting input of the first operational amplifier.

5. Apparatus according to claim 2 , characterized in that
the charge amplifier comprises at least a first and at least a second operational amplifier, wherein the inverting input of the first operational amplifier is connected to the first terminal of the at least one sensing capacitor and the inverting input of the second operational amplifier is connected to the second terminal of the at least one sensing capacitor, and wherein the first capacitor is connected between the output of the first operational amplifier and the inverting input of the first operational amplifier and the second capacitor is connected between the output of the second operational amplifier and the inverting input of the second operational amplifier.

6. Apparatus according to claim 5 , characterized in that
a third operational amplifier is connected to the output of the first and the second operational amplifier.

7. Apparatus according to claim 1 , characterized in that
the at least one sensing capacitor is coupled to a printed circuit board (PCB).

8. Apparatus according to claim 7 , characterized in that
the PCB comprises cuts in form of segments of a circle, wherein at least a first and at least a second cut are arranged symmetrically and mirrored around the centre of the circle, and wherein the at least one sensing capacitor is coupled to the PCB at the centre of the circle or between the first and second cuts.

9. Apparatus of claim 7 , further comprising:
an inertia is coupled to the PCB at the centre of the circle,
a charge amplifier or parts of a charge amplifier are connected between the at least one sensing capacitor and the controller and the charge amplifier or parts of the charge amplifier are coupled to the PCB at the centre of the circle;

wherein
the controller is configured to determine an amount of force applied to the sensing capacitor or an acceleration of the sensing capacitor applied to the sensing capacitor based on the change of charge of the at least one sensing capacitor, and
a charge amplifier or parts of a charge amplifier are connected between the at least one sensing capacitor and the controller is coupled to the PCB between and in equally spaced from the at least two longitudinal cuts.

10. Apparatus according to claim 9 , characterized in that
the controller is configured to determine an amount of force applied to the sensing capacitor or an acceleration of the sensing capacitor applied to the sensing capacitor based on the change of charge of the at least one sensing capacitor.

11. Apparatus according to claim 7 , characterized in that
the PCB comprises at least two longitudinal cuts arranged in parallel to each other, and wherein the at least one sensing capacitor is coupled to the PCB between and equally spaced from the at least two longitudinal cuts.

12. Apparatus according to claim 7 , characterized in that
a first sensing capacitor is coupled to a first side of the PCB and a second sensing capacitor is coupled to a second side opposite to the first side of the PCB, wherein the first and the second sensing capacitor are coupled to the PCB adjacent or directly opposite to each other.

13. Apparatus according to claim 12 , characterized in that
the PCB is of a longitudinal shape having a first end and a second end opposite to the first end and two longitudinal ends, wherein the first end is affixable and the second end is moveable, and wherein a charge amplifier or parts of a charge amplifier are connected between at least one of the first and second sensing capacitors and the controller, and wherein the controller is coupled to the PCB adjacent to the first end and wherein the first and the second sensing capacitor is coupled in a first distance from the first end to the PCB.

14. Apparatus according to claim 11 , characterized in that
the controller is configured to determine an oscillation of the PCB based on an amount of force applied to the first and the second sensing capacitor based on the change of charge of the first and the second sensing capacitor.

15. Apparatus according to claim 7 , characterized in that
the PCB is of a longitudinal shape having a first end and a second end opposite to the first end and two longitudinal ends, wherein the first end is affixable and the second end is rotatable, and wherein the two conductors and the dielectric of the at least one sensing capacitor is coupled to the PCB vertically to the rotation axis of the PCB;
the controller is configured to determine a torsion force applied to the sensing capacitor based on the change of charge of the at least one sensing capacitor;
the PCB is of a longitudinal shape having a first end and a second end opposite to the first end and two longitudinal ends, wherein the first end is affixable and the second end is moveable, and wherein the at least one sensing capacitor is coupled to the PCB adjacent to and spaced from the first end of the PCB in a first distance, and wherein the charge amplifier is coupled to the PCB adjacent to and spaced from the first end of the PCB in a second distance, the second distance being smaller than the first distance; and wherein
the controller is configured to determine a vibration of the sensing capacitor based on the change of charge of the at least one sensing capacitor.

16. Apparatus according to claim 7 , characterized in that
the PCB is arranged within a pressure cell, and wherein the PCB divides the pressure cell into a first and a second pressure chamber, and wherein the first pressure chamber comprises a first opening for applying a first pressure to the first pressure chamber and the second pressure chamber comprises a second opening for applying a second pressure to the second pressure chamber, and wherein a first sensing capacitor is coupled to a first side of the PCB and a second sensing capacitor is coupled to a second side opposite to the first side of the PCB, wherein the first and the second sensing capacitor are coupled to the PCB adjacent or directly opposite to each other;

the controller is configured to determine a differential pressure applied to the first and the second sensing capacitor based on the change of charge of the first and the second sensing capacitor;
the PCB is of a longitudinal shape having a first end and a second end opposite to the first end and two longitudinal ends, wherein the first end is affixable and the second end is moveable, and wherein the two conductors and the dielectric of the at least one sensing capacitor is coupled to t

Assignees

• Texas Instruments Inc

Inventors

• Gossner Kai

Classifications

• G01C19/5719

  using planar vibrating masses driven in a translation vibration along an axis · CPC title

• G01P15/125

  by capacitive pick-up · CPC title

• H01G5/38

  Multiple capacitors, e.g. ganged · CPC title

• G01L1/148 Primary

  using semiconductive material, e.g. silicon · CPC title