Piezoelectric shock wave generator

• US 5,119,801 A
• Filed: 10/15/1991
• Issued: 06/09/1992
• Est. Priority Date: 02/04/1988
• Status: Expired due to Fees

• Current Assignee: Dornier Medizintechnik GmbH
• Original Assignee: Dornier Medizintechnik GmbH
• Inventors: Eizenhoefer, Harald, Marlinghaus, Ernst
• Primary Examiner(s): Cohen, Lee S.
• Assistant Examiner(s): Pfaffle, Krista M.
• Application Number:
  US07/779,113
• Time in Patent Office: 238 Days
• Field of Search: 128/24 AA, 128/24 EL, 128/662.03, 128/660.01, 310/335, 310/337, 310/311, 310/313 A
• US Class Current: 601/4
• CPC Class Codes: A61B 17/225 for extracorporeal shock wave lithotripsy [ESWL], e.g. by using ultrasonic waves
• CPC Class Codes: B06B 1/0622 on one surface
• CPC Class Codes: G10K 15/043 producing shock waves G10K15/046, G10K15/06 take precedence; generating seismic energy G01V1/02

Abstract

A piezoelectric shock wave generator for use in medical equipment includes a plurality of piezoelectric elements being electrically interconnected to operate in parallel and mounted on a common carrier of curved configuration; a coupler medium couples shock waves as generated by these piezoelectric generators into the body of a living being, the improvement includes electrical insulation between the piezoelements being in fluid, i.e. liquid or gaseous state, in that each piezoelectric element is surrounded by the fluid in any direction towards any other piezoelectric element; the front ends of the piezoelectric elements may be physically separated, so that the coupler fluid and the isolating fluid are the same, and having a common flow space; alternatively, a membrane in front of all said piezoelectric elements provides electrical interconnection between them and physically separates the isolating fluid from the coupler liquid.

Claims

1. In a piezoelectric shock wave generator for use in medical equipment and including a plurality of piezoelectric elements being electrically interconnected to operate in parallel and mounted on a common carrier, there being a coupler medium for coupling shock waves as generated by these piezoelectric elements into the body of a living being, wherein the improvement comprises an electrical insulation between the piezoelectric elements being in a fluid state, in that each of said piezoelectric elements is surrounded by the fluid insulation, and in any direction towards any other of the piezoelectric elements, said insulation having a breakthrough strength in excess of about 5 KV/mm, being larger than the breakthrough strength of air.

2. Generator as in claim 1 wherein front ends of the piezoelectric elements are physically separated, said coupler medium and said insulation fluid being the same and having a common flow space.

3. Generator as in claim 1 there being a membrane in front of all said piezoelectric elements providing electrical interconnection between them and physically separating said insulation fluid from said coupler medium.

4. Generator as in claim 2 further comprising individual impedance matching devices in front of each of said piezoelectric elements.

5. Generator as in claim 1, wherein rear ends of said piezoelectric elements are embedded in said carrier.

6. Generator as in claim 1 further comprising wire loops interconnecting front ends of adjacent piezoelectric elements.

7. In a piezoelectric shock wave generator for use in medical equipment and including a plurality of piezoelectric elements being electrically interconnected to operate in parallel and mounted on a common carrier, there being a coupler liquid for coupling shock waves as generated by these piezoelectric elements into the body of a living being, wherein the improvement comprises an electrical insulation between the piezoelectric elements being a liquid, in that each of said piezoelectric elements is surrounded by the liquid, and in any direction towards any other of the piezoelectric elements, said insulation liquid having a breakthrough strength in excess of about 5 KV/mm which is larger than the breakthrough strength of air.