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:
Jun. 27, 1995
Filed:
May. 24, 1994
Kazushi Nakata, Osaka, JP;
Shigenori Matsushita, Osaka, JP;
Shigeru Yamamoto, Osaka, JP;
Shu h-uai Zhang, Osaka, JP;
Satoru Nihsida, Osaka, JP;
Kabushiki Kaisha Komatsu Seisakusho, Tokyo, JP;
Abstract
In an apparatus for controlling the vertical movement of a scraper blade (18) of a bulldozer, a four-position hydraulic control valve (12), having HOLD, UP, DOWN, and FLOAT positions, maintains the scraper blade in the FLOAT condition without requiring a detent mechanism, even when the three-position operation lever (1, 51) is released with the hydraulic control valve (12) in the FLOAT position. The operation lever (1, 51), having HOLD, UP, and DOWN positions, provides electrical signals to a controller (4) for actuating the hydraulic control valve (12) with pilot pressures provided via solenoid pilot valves (6, 7). A hydraulic cylinder (19), connected to the scraper blade (18), is actuated by hydraulic oil from the hydraulic control valve (12). A control device (2, 52), for generating an electrical signal for the FLOAT position and transmitting that electrical signal to the controller (4), is provided on the three-position operation lever (1, 51), so that the hydraulic control valve (12) is held at the FLOAT position in response to the electrical signal from the control device (2, 52).