Karl M. Groetschel

Follow

Person

8 Munchen 40, DE

People

Patents Grantslast 30 patents

Information Patent Grant
Method of and apparatus for applying mat to the roof of a mine working
- Patent number 4,379,660
- Issue date Apr 12, 1983
- Karl M. Groetschel
- E21 - EARTH DRILLING MINING
Information Patent Grant
Recorder control apparatus and method
- Patent number 4,369,362
- Issue date Jan 18, 1983
- Karl M. Groetschel
- G06 - COMPUTING CALCULATING COUNTING
Information Patent Grant
Apparatus for supporting the roof of an underground mine working
- Patent number 4,358,159
- Issue date Nov 9, 1982
- Karl M. Groetschel
- E21 - EARTH DRILLING MINING
Information Patent Grant
Fastening means for roof mats for mine workings
- Patent number 4,251,168
- Issue date Feb 17, 1981
- Karl M. Groetschel
- E21 - EARTH DRILLING MINING
Information Patent Grant
Method of and apparatus for preselecting operation of television or...
- Patent number 4,222,069
- Issue date Sep 9, 1980
- Karl M. Groetschel
- H04 - ELECTRIC COMMUNICATION TECHNIQUE
Information Patent Grant
Methods of and apparatus for applying roof mats to mine workings
- Patent number 4,122,682
- Issue date Oct 31, 1978
- Karl M. Groetschel
- E21 - EARTH DRILLING MINING