Acceleration transducer

Patent metadata

Field	Value
Publication number	US-11754589-B2
Application number	US-202117513977-A
Country	US
Kind code	B2
Filing date	Oct 29, 2021
Priority date	Nov 2, 2020
Publication date	Sep 12, 2023
Grant date	Sep 12, 2023

Abstract

An acceleration transducer defines a rectangular coordinate system with two orthogonal horizontal axes that are both normal to a vertical axis and includes a main body disposed within a housing and defining tangential side faces arranged tangentially to the vertical axis, and a normal side face arranged normally to the vertical axis. A piezoelectric element is secured to one of the tangential side faces, and a seismic mass secured to the piezoelectric element. A signal output is attached to the housing and includes a signal conductor spaced apart by an assembly gap from a tangential side face that is not attached to the piezoelectric element. The assembly gap extends perpendicularly to the vertical axis. The normal side face includes main body output conductors spanning the assembly gap in a direction perpendicular to the vertical axis and directly contacting the signal conductor.

First claim

What is claimed is:

1. An acceleration transducer arranged in a rectangular coordinate system with three mutually orthogonal axes, one of the three axes being a transverse axis, one of the three axes being a longitudinal axis, one of the three axes being a vertical axis, the acceleration transducer comprising:
a housing;
a main body disposed within the housing and defining a first tangential side face lying in a first plane, a second tangential side face lying in a second plane that is disposed spaced apart from and normal to the first plane, a third tangential side face lying in a third plane that is disposed spaced apart from and parallel to the first plane, and a fourth tangential side face lying in a fourth plane that is disposed spaced apart from and parallel to the second plane, wherein each of the first, second, third and fourth tangential side faces is disposed tangentially to the vertical axis;
wherein the main body further defines a lower normal side face lying in a fifth plane that is normal to each of the first, second, third and fourth planes, and wherein the main body further defines an upper normal side face lying in a sixth plane that is disposed spaced apart along the vertical axis from and parallel to the fifth plane;
exactly three piezoelectric elements, which include only a first piezoelectric element secured to the first tangential side face, a second piezoelectric element secured to the second tangential side face, and a third piezoelectric element secured to the third tangential side face;
exactly three seismic masses, which include only a first seismic mass secured to the first piezoelectric element so that acceleration of the first seismic mass exerts on the first piezoelectric element a first shear force proportional to the acceleration, a second seismic mass secured to the second piezoelectric element so that acceleration of the second seismic mass exerts on the second piezoelectric element a second shear force proportional to the acceleration, and a third seismic mass secured to the third piezoelectric element so that acceleration of the third seismic mass exerts on the third piezoelectric element a third shear force proportional to the acceleration, wherein each of the three piezoelectric elements generates piezoelectric charges under the action of each respective shear force; and
a signal output attached to the housing and including a signal conductor that is spaced apart by an assembly gap from the fourth tangential side face to which no piezoelectric element is attached, wherein the assembly gap extends in a direction perpendicularly to the vertical axis;
a main body output conductor spanning the assembly gap perpendicularly to the vertical axis and directly connected to the signal conductor, wherein the main body output conductor is defined by one of the following: the lower normal side face of the main body, the upper normal side face of the main body, a support that is attached to either the lower normal side face of the main body or to the upper normal side face of the main body;
wherein each of the three piezoelectric elements defines end faces; and
wherein each of the three piezoelectric elements is configured with a high sensitivity for a shear force exerted by the respective seismic mass secured to each of the three piezoelectric elements; and
wherein each of the three piezoelectric elements is further configured to generate piezoelectric charges on the end faces under the action of the shear force;
wherein the piezoelectric element comprises lateral surfaces;
wherein a first end face comprises a first electrically conductive end face coating;
wherein a second end face comprises a second electrically conductive end face coating;
wherein a first lateral surface comprises a first electrically conductive lateral surface coating and a further first electrically conductive lateral surface coating;
wherein the first electrically conductive end face coating and the first electrically conductive lateral surface coating form a continuous first electrically conductive coating; and
wherein the second electrically conductive end face coating and the further first electrically conductive lateral surface coating form a continuous second electrically conductive coating.

2. The acceleration transducer according to claim 1 , further comprising a converter unit that is attached to the lower normal side face or to the support attached to the lower normal side face;
wherein the converter unit includes a plurality of first piezoelectric element conductors and a plurality of second piezoelectric element conductors;
wherein the first electrically conductive lateral surface coating is materially bonded to a first one of the plurality of first piezoelectric element conductors;
wherein the further first electrically conductive lateral surface coating is materially bonded to a first one of the plurality of second piezoelectric element conductors;
wherein the first one of the plurality of first piezoelectric element conductors is configured to receive piezoelectric charges from the first electrically conductive lateral surface coating and configured to transmit them as the first acceleration signals; and
wherein the first one of the plurality of second piezoelectric element conductors is configured to receive piezoelectric charges from the further first electrically conductive lateral surface coating and configured to transmit them as the second acceleration signals.

3. The acceleration transducer according to claim 2 , wherein the converter unit comprises a plurality of first main body conductors and a plurality of second main body conductors and a plurality of transimpedance transducers;
wherein the first one of the plurality of first piezoelectric element conductors is contacted with a first one of the plurality of first main body conductors;
wherein a first one of the plurality of first main body conductors is configured to transmit the first acceleration signals to a first one of the plurality of transimpedance transducers, which the transimpedance converter is configured to convert the first acceleration signals;
wherein a first one of the plurality of second piezoelectric element conductors is contacted with a first one of the plurality of second main body conductors; and
wherein the first one of the plurality of second main body conductors is configured to transmit the second acceleration signals.

4. The acceleration transducer according to claim 3 , wherein the first one of the plurality of first main body conductors is contacted with a first one of a plurality of first main body output conductors, which is configured to transmit the converted first acceleration signals to the signal output; and
wherein the first one of the plurality of second main body conductors is contacted with a second main body output conductor, which is configured to transmit the converted second acceleration signals to the signal output.

5. An acceleration transducer arranged in a rectangular coordinate system with three mutually orthogonal axes, one of the three axes being a transverse axis, one of the three axes being a longitudinal axis, one of the three axes being a vertical axis, the acceleration transducer comprising:
a housing defining a housing bottom and defining a housing opening disposed opposite the housing bottom, wherein the housing further defining a cable opening;
a main body disposed within the housing and defining a cuboid shape that includes:
an upper end defining an upper end face lying in an upper plane that is normal to the vertical axis,
a lower end connected to the housing bottom and defining a lower end face spaced apart along the vertical axis from the upper end face and lying in a lower plane that is normal to the vertical axis and parallel to the upper plane,
a first

Assignees

• Kistler Holding Ag

Inventors

• Laffranchi Marco
• Frommenwiler Tobias
• Weber David

Classifications

• G01P15/09 Primary

  by piezoelectric pick-up · CPC title

• G01P15/18 Primary

  in two or more dimensions · CPC title

• G01P1/023

  for acceleration measuring devices · CPC title

• G01P15/0915

  of the shear mode type · CPC title

• G01P15/097

  by vibratory elements · CPC title