Hydraulic system for operation of a winch

• US 4,188,790 A
• Filed: 10/04/1978
• Issued: 02/19/1980
• Est. Priority Date: 02/21/1974
• Status: Expired due to Term

• Current Assignee: A/S Bergens Mekaniske Verksteder
• Original Assignee: A/S Bergens Mekaniske Verksteder
• Inventors: Pedersen, Hakon S.
• Primary Examiner(s): Geoghegan, Edgar W.
• Application Number:
  US05/948,551
• Time in Patent Office: 503 Days
• Field of Search: 60/483, 60/484, 60/485, 60/905, 91/508, 254/172, 74/661, 74/665 R
• US Class Current: 60/483
• CPC Class Codes: B66D 1/44 pneumatic of hydraulic
• CPC Class Codes: Y10S 60/905 Winding and reeling

Abstract

Hydraulic system for operation of a winch, including a hydraulic motor for operation of the winch, a pump for pumping hydraulic oil for operation of the motor, a manoeuvering valve for control of the speed of the motor and rotational direction, a first choke valve which is connected in series with the pump, and a second choke valve which is connected in parallel with the motor, the system including two or more hydraulic motors connected in parallel, with throughflow both ways, preferably of the multi-stage type, and drive-connected to the same winch shaft.

Claims

1. A hydraulic system operating in combination with a winch, comprising at least two hydraulic motors connected in parallel for operation of the winch, pump means for supplying oil to the motors, a control valve for controlling the speed and direction of rotation of the motors, one of the motors having a dual capacity and a valve for selecting the capacity of the dual capacity motor, means for selectively coupling the motors to the oil supply to provide a plurality of speed ranges, a return connection for the oil to the pump, and means to restrict flow in the return connection to provide a braking action on the motors when the motors are driven by the load.

2. A hydraulic system as claimed in claim 1, said pump means comprising a plurality of fixed capacity pumps operating in parallel.