Piezoelectric-based multiple impact sensors and their electronic circuitry

Patent metadata

Field	Value
Publication number	US-9910060-B2
Application number	US-201514589933-A
Country	US
Kind code	B2
Filing date	Jan 5, 2015
Priority date	Jul 10, 2007
Publication date	Mar 6, 2018
Grant date	Mar 6, 2018

Abstract

An electrical energy harvesting device for harvesting electrical energy from a pulsed impact loading event. The device including: a piezoelectric element configured to be loaded and unloaded to a first load level by the pulsed impact loading event; and a first inductor coupled to the piezoelectric element configured to be loaded and unloaded to a second load level by the pulsed impact loading event, wherein the piezoelectric element and the first inductor together operate as a first inductor/capacitor (LC) resonant circuit having a first resonance frequency and wherein the loading of the first inductor lags in time the loading of the piezoelectric element.

First claim

What is claimed is:

1. A shock detection circuit comprising:
a piezoelectric device configured to generate a voltage over a duration responsive to one or more shock loading events;
an electrical storage device configured to receive the generated voltage to accumulate a charge;
an energy dissipating device coupled to the electrical storage device and configured to dissipate the accumulated charge at least one of before and after the one or more shock loading events and not to substantially dissipate the accumulated charge during the one or more shock loading events;
a detector coupled to the electrical storage device and configured to detect a portion of the accumulated charge;
a housing containing the shock detection circuit, wherein the piezoelectric device is fixed to a first portion of an interior surface of the housing; and
a compressively preloaded elastic element positioned between a second portion of the interior surface of the housing and the piezoelectric device to configure the piezoelectric device to generate a voltage responsive to acceleration in at least two opposite directions.

2. The shock detection circuit of claim 1 , wherein the energy dissipating device comprises a diode and a resistor coupled in series to the electrical storage device.

3. The shock detection circuit of claim 1 , wherein the energy dissipating device comprises a capacitor and a resistor coupled in series to the electrical storage device to dissipate the accumulated charge related to mechanical residual energy.

4. The shock detection circuit of claim 1 , wherein the detector is configured to compare a voltage at each of a plurality of outputs coupled to the electrical storage device to a corresponding reference voltage to produce a corresponding plurality of accumulated charge results based on the plurality of comparisons.

5. The shock detection circuit of claim 1 , wherein the shock detection circuit is a portion of an all-fire detection circuit for an electrically initiated inertial igniter munition.

6. The shock detection circuit of claim 1 , comprising a control circuit, wherein the energy dissipating device comprises a switch and a resistor coupled in series to the electrical storage device and the control circuit is configured to detect an end of the one or more shock loading events to close the switch and connect the resistor to the electrical storage device until the accumulated charge is below a predetermined voltage.

7. The shock detection circuit of claim 6 , wherein the control circuit is configured to determine whether the shock loading event has occurred within a predetermined period of time and to connect the resistor to the electrical storage device only during the predetermined period.

8. The shock detection circuit of claim 1 , comprising a platform and a vibration isolation layer wherein the housing is attached to the platform through the vibration isolation layer.

9. A shock detection circuit comprising:
a piezoelectric device configured to generate a voltage over a duration responsive to one or more shock loading events;
an electrical storage device configured to receive the generated voltage to accumulate a charge;
an energy dissipating device coupled to the electrical storage device and configured to dissipate the accumulated charge at least one of before and after the one or more shock loading events and not to substantially dissipate the accumulated charge during the one or more shock loading events;
a detector coupled to the electrical storage device and configured to detect a portion of the accumulated charge; and
a housing containing the shock detection circuit, wherein the piezoelectric device is fixed to a first portion of an interior surface of the housing;
wherein the energy dissipating device comprises a capacitor and a resistor coupled in series to the electrical storage device to dissipate the accumulated charge related to mechanical residual energy; and
an inductor is coupled to the resistor in series with the diode and the resistor, wherein the inductor, the diode and the resistor are selected to be responsive to one or more frequencies within a selected range corresponding to a dominant mode of vibration of the housing.

10. A shock detection circuit comprising:
a piezoelectric device configured to generate a voltage over a duration responsive to one or more shock loading events;
an electrical storage device configured to receive the generated voltage to accumulate a charge;
an energy dissipating device coupled to the electrical storage device and configured to dissipate the accumulated charge at least one of before and after the one or more shock loading events and not to substantially dissipate the accumulated charge during the one or more shock loading events; and
a detector coupled to the electrical storage device and configured to detect a portion of the accumulated charge;
wherein the detector is a processor that is configured to record the detected portion of the accumulated charge.

11. The shock detection circuit of claim 10 , wherein the processor is configured to record results including the detected portion of the accumulated charge together with an indication of when the detected portion of the accumulated charge occurred.

12. The shock detection circuit of claim 11 , wherein the detector is configured to continuously record results together with an indication of when each of the plurality of results occurred.

13. The shock detection circuit of claim 10 , wherein the processor is configured to record a plurality of detected portions of the accumulated charge together with an indication of when each of the plurality of the detected portions of the accumulated charge occurred.

14. A shock detection circuit comprising:
a piezoelectric device configured to generate a voltage over a duration responsive to one or more shock loading events;
an electrical storage device configured to receive the generated voltage to accumulate a charge;
an energy dissipating device coupled to the electrical storage device and configured to dissipate the accumulated charge at least one of before and after the one or more shock loading events and not to substantially dissipate the accumulated charge during the one or more shock loading events; and
a detector coupled to the electrical storage device and configured to detect a portion of the accumulated charge;
wherein the detector is configured to compare a voltage at each of a plurality of outputs coupled to the electrical storage device to a corresponding reference voltage to produce a corresponding plurality of accumulated charge results based on the plurality of comparisons; and
the reference voltages are selected so that each of the plurality of results are an indication of different levels of an impact.

15. A shock detection circuit comprising:
a piezoelectric device configured to generate a voltage over a duration responsive to one or more shock loading events;
an electrical storage device configured to receive the generated voltage to accumulate a charge;
an energy dissipating device coupled to the electrical storage device and configured to dissipate the accumulated charge at least one of before and after the one or more shock loading events and not to substantially dissipate the accumulated charge during the one or more shock loading events; and
a detector coupled to the electrical storage device and configured to detect a portion of the accumulated charge;
wherein the detector is configured to record a plurality of accumulated charge results together with an indication of when each of the plurality of results occurred.

Assignees

• Rastegar Jahangir S
• Omnitek Partners Llc

Inventors

• Rastegar Jahangir S

Classifications

• G01P15/001 Primary

  by measuring acceleration changes by making use of a triple differentiation of a displacement signal · CPC title

• B01J31/2265

  Carbenes or carbynes, i.e.(image) · CPC title

• H02N2/183

  using impacting bodies (high voltage generators in spark lighters F23Q) · CPC title

• F42C11/02

  with piezo-crystal · CPC title

• C07F11/00

  Compounds containing elements of Groups 6 or 16 of the Periodic Table · CPC title