GB569477A - Improvements in or relating to systems for driving vessels - Google Patents

Abstract

569,477. Fluid-pressure servomotorcontrol systems . HAMMOND, J. H. May 5, 1943, No. 7126. [Class 135] The pitch of a ship's propeller is varied in accordance with the integrated value, over a definite period of time, of the deviation from normal of a condition of propulsion. The form shown includes mechanism comprising a pointer 53 indicating propeller thrust and controlling a motor 55 in the manner described in Specification 546,197. The motor acts through a reducing gear 85 and a threaded shaft 86 on a rider 87, operatively connected to an arm 90 having a contact 92. A timing device comprises a cam 101, and the arrangement is such that while the high part of the cam lifts a roller 102, the contacts 103, 105 are in engagement, the motor 55 is driven, and the contact 92 is moved to a position proportional to the integrated deviation of thrust from normal. When the low part of the cam operates, .contact is broken at 103, 105 and established at 103, 106, so that the motor 55 is stopped, and a motor 21 driven through establishment of contact between 92 and 95 or 96, to move a lever 23 controlling a servomotor 27 which operates a rod 19 controlling the propeller pitch. Forms are also described in which the pointer 53 is operated in accordance with the ship's speed, or by the steam consumption.