Method for producing an acceleration sensor

Patent metadata

Field	Value
Publication number	US-9841434-B2
Application number	US-201414766566-A
Country	US
Kind code	B2
Filing date	Feb 6, 2014
Priority date	Feb 7, 2013
Publication date	Dec 12, 2017
Grant date	Dec 12, 2017

Abstract

The invention relates to a method for producing an acceleration sensor having a housing ( 1 ), which has a cylindrical or cubic basic shape, having at least one internal support ( 4 ) and having a sensor element ( 2 ) arranged thereon. According to the invention a sensor element ( 2 ) comprising a main body ( 29 ) having a head part ( 21 ) and an end face ( 24 ) opposing said head part ( 21 ) is premounted, by surrounding the head part ( 21 ) with at least one piezoelectric measuring element ( 23 ), a seismic composition ( 22 ) and a clamping ring ( 27 ). The end face ( 24 ) is subsequently positioned on the inner support ( 4 ) of the housing ( 1 ) in contact therewith to form a contact zone ( 7 ) between the end face ( 24 ) and the support ( 4 ). Finally, the sensor element ( 2 ) is welded in this contact zone ( 7 ) to the housing ( 1 ). The invention further relates to an acceleration sensor produced using said method.

First claim

The invention claimed is:

1. A method for producing an acceleration sensor for use in machines, systems, vehicles or aircraft, wherein the acceleration sensor comprises a housing defining an outer shell having an interior surrounded by an exterior, which is cylindrical or cubic in terms of its basic exterior shape, the housing further defining at least one internal support, the acceleration sensor including at least one sensor element arranged on the at least one internal support, the at least one sensor element including at least one piezoelectric measuring element and a base body having a head part and an end face opposite the head part, the end face defining an annular elevation surrounded by a groove, each of the at least one internal support and the at least one sensor element being disposed within the interior of the outer shell of the housing, the method comprising;
a) pre-installing the at least one sensor element by encompassing the head part of the base body with the at least one piezoelectric measuring element, and enclosing the sensor element with a seismic mass and a clamping ring,
b) forming a contact zone between the end face and the at least one internal support by positioning only the annular elevation of the end face in contact with the at least one internal support in the interior of the outer shell of the housing, and
c) constructing a materially-bonded connection at the contact zone by welding the end face on the at least one internal support.

2. The method according to claim 1 , wherein the welding comes about by resistance welding, in that a welding electrode is contacted with the head part of the at least one sensor element and a counter electrode is contacted on the housing, and subsequently a defined voltage for generating a current flow between the welding electrode, the at least one sensor element, the housing and the counter electrode is applied for constructing the materially-bonded connection at the contact zone.

3. The method according to claim 2 , wherein the welding electrode for the resistance welding is applied onto the head part of the at least one sensor element with a defined force.

4. The method according to claim 1 , wherein the welding comes about by friction welding.

5. The method according to claim 1 , further comprising the step of attaching measuring electronics on the at least one internal support or on the head part.

6. The method according to claim 1 , wherein the at least one internal support and two additional supports are provided in the housing and each of the at least one internal support and the two additional supports is respectively connected in a materially-bonded manner to one of a plurality of sensor elements that includes the at least one sensor element.

7. The method according to claim 1 , further comprising the steps of: subsequently to the method step c), closing the housing above the at least one sensor element with respect to the outside and contacting the at least one piezoelectric measuring element using a connector plug.

8. The method according to claim 1 , wherein in step b), the contact zone is formed by contacting a jointing surface on the at least one internal support with tips of the annular elevation of the end face of the base body of the at least one sensor element.

9. The method according to claim 1 , wherein the annular elevation is at least partially melting in the contact zone during the welding step.

10. An acceleration sensor for measuring acceleration values in one or three axes, wherein the acceleration sensor comprises:
a housing defining an outer shell having an interior surrounded by an exterior, which is cylindrical or cubic in terms of its basic exterior shape, the housing further defining a plurality of internal supports disposed within the interior of the outer shell of the housing;
a plurality of sensor elements, wherein each of the plurality of sensor elements is arranged on a respective one of the plurality of internal supports, each of the plurality of sensor elements including a base body having a head part and an end face opposite the head part, the end face defining an annular elevation surrounded by a groove, each of the plurality of internal supports and the plurality of sensor elements being disposed within the interior of the outer shell of the housing, each of the plurality of sensor elements including at least one piezoelectric measuring element encompassing the head part of the base body;
each of the plurality of sensor elements including a respective seismic mass and a respective clamping ring enclosing said each of the plurality of sensor elements;
wherein, for each of the plurality of sensor elements, by positioning only the annular elevation of the end face in contact with the respective one of the plurality of internal supports in the interior of the outer shell of the housing, a contact zone is formed between the end face and the respective one of the plurality of internal supports;
wherein each end face is welded at each contact zone on each of the plurality of internal supports to form a materially-bonded connection.

11. The acceleration sensor according to claim 10 , wherein the housing consists of a titanium material or an aluminium material.

12. The acceleration sensor according to claim 10 wherein the base bodies of the plurality of sensor elements consist of titanium or steel.

13. The acceleration sensor according to claim 10 , wherein each of the plurality of sensor elements is configured in a pin-shaped manner, in that each of the plurality of sensor elements has an axis transverse to the end face and the end face is axially spaced from the at least one piezoelectric measuring element and also from the respective seismic mass and the respective clamping ring.

Assignees

• Kistler Holding Ag

Inventors

• Sonderegger Christof
• Tack Peter Charles

Classifications

• G01P1/023 Primary

  for acceleration measuring devices · CPC title

• B23K11/20

  of different metals · CPC title

• G01P15/0802 Primary

  Details · CPC title

• G01P15/09

  by piezoelectric pick-up · CPC title

• B23K11/087

  for rectilinear seams · CPC title