IP Library › Granted Patent US 4,230,022
Granted Patent Utility
US 4,230,022 · App. 06/001,492

Hydraulic rock breaker circuit for an excavator

Inventors: Donald L. Bianchetta, Lawrence F. Schexnayder
Patented Case View Patent ↗
Granted: Oct 28, 1980 Filed: Jan 8, 1979
Inventors
Donald L. Bianchetta
Lawrence F. Schexnayder
Assignee (at issue)
Caterpillar Tractor Co.

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Quick Facts
Patent No.
US 4,230,022
App. No.
06/001,492
Filed
1979-01-08
Granted
1980-10-28
Kind
A