The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Dec. 09, 2025
Filed:
Oct. 25, 2021
Caterpillar Inc., Peoria, IL (US);
Ernest E. Stoops, Mt. Zion, IL (US);
Nathaniel K. Harshman, Sullivan, IL (US);
Jonathan M. Bloot, Tucson, AZ (US);
Caterpillar Inc., Peoria, IL (US);
Abstract
A hydraulic system for operating a circle drive gear of a grading machine includes a pump configured to output pressurized fluid, a directional control valve fluidly coupled to the pump, a bidirectional hydraulic motor located downstream of the directional control valve and fluidly coupled to the directional control valve via hydraulic lines. The hydraulic motor has an output shaft that is configured to be rotationally driven by pressurized fluid output by the pump. Dual counterbalance valves may be disposed within the hydraulic circuit of the directional control valve and hydraulic motor such that any gearbox driven by the hydraulic motor is protected from external opposing forces. Accordingly, motion in the circle drive system is hydraulically locked at the beginning and release of a circle rotation command with the help of fluid pressure in the hydraulic lines.