| 摘要 |
<p>1,255,567. Power steering mechanism. CATERPILLAR TRACTOR CO. 22 Dec., 1969 [24 Jan., 1969], No. 62368/69. Heading B7H. [Also in Division F2] A valve for use in controlling flow of pressurized fluid to a double-acting steering-jack 10 between the two articulated sections of a scraper vehicle has a spool 22 with annular recesses 48, 50 for communicating the work ports 32, 34 with either the inlet 30 or the outlets 40, 42. Each recess has associated therewith grooves 52, 54, 56, 58 which communicate with each other and the respective recess and are of different widths to modulate the rate of flow as the valve is opened. Narrow grooves 56, 58 allow flow in valve closed position to prevent cavitation. The spool is moved by a steering wheel 26, nut 28 and pivoted link 29. Spring 24 biases the spool to valve closed position and spring 60 provides " feel " at large valve openings.</p> |
