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. 18, 2001
Filed:
Mar. 04, 1999
Masami Kondo, Osaka, JP;
Yanmar Diesel Engine Co., Ltd., Osaka, JP;
Abstract
A hydraulic circuit which, when applied to a turning excavator having hydraulic actuators for the working arms and the turning excavator body supplied with pressure oil from three pumps, can increase the operation speed of the booms and arms without providing a separate hydraulic pump to improve the work efficiency. During the individual driving, the boom cylinder (CY,) is supplied with a pressure oil from the first and third pumps (P,, P,), the arm cylinder (CY,) from the second and third pumps (P,, P,), the bucket cylinder (CY,) from the first pump (P,), and the turning motor (M) from the third pump (P,). During the simultaneous driving of the boom and arm cylinders (CY,, CY,), the arm is supplied with an operation speed increasing pressure oil from the third pump (P,). When the boom cylinder (CY,) and the turning motor (M) are simultaneously operated, a part of the pressure oil to the turning motor (M) from the third pump (P,) is supplied to the boom cylinder (CY,).