GB1021865A - Winching system - Google Patents

Abstract

1,021,865. Winches; trimming apparatus. FREDERICK PARKER Ltd. April 3, 1964 [April 4, 1963], No. 13301/63. Headings B8B and B8E. A winching system 6 for pulling in a shovel 5 of a concrete mixer 1 comprises a winch drum 22 driven through a freewheel device 23 from an hydraulic motor 12 which has its hydraulic supply controlled by a reversing valve 34 operable by a switch 9 on the shovel 5. The winch drum 22 is mounted outside of a casing 10, 11, 19 and on a shaft 20 driven through a worm and wheel 17, 18 from a shaft 15 normal thereto. The shaft 15 is driven through a flexible coupling 14 from the output shaft 13 of the hydraulic motor 12. The motor 12 is of the gear type in which the gears, one of which has the output shaft 13 attached thereto, may be driven in either direction by fluid supplied from a reservoir 37 by a constantly operating gear pump 33. The reversing valve 34 has a spool 38 actuated by a solenoid 39 against a spring 40, to cause a reverse rotation of the motor 12 which drives the winch drum 22. The solenoid is energized by closure of the remote switch 9. Upon de-energization of the solenoid, the spool is returned under the action of spring 40 and the motor 12 is driven forwardly, in which direction the winch drum 22 free wheels. A stub shaft 25 on the winch drum shaft 20 is subject to braking by resilient brake strips 27 loaded against the stub shaft by a spring 28 subjected to loading by a screwed nut. The electrical lead 41 from the switch 9 to the solenoid 39 passes over a jib supported pulley 43 with a loop passing around a loose pulley 44 to take up excess length of lead.