公开(公告)号：CA1208993A

公开(公告)日：1986-08-05

申请号：CA440572

申请日：1983-11-07

Applicant: UNITED TECHNOLOGIES CORP

Inventor： DUCHESNEAU JEROME G ,  SCHWARTZ ROBERT A

IPC: B63H3/10 ,  B64C11/38 ,  B64C11/40 ,  F02K3/04 ,  B63H3/00

Abstract: Pitch Control System For Variable Pitch Propeller A pitch control system (10) for a variable pitch propeller effects engine governor (330), control of blade pitch under normal operating conditions and automatically effects direct (beta) control of blade pitch by the power lever (305) throughout a predetermined range of power lever settings, The system is hydromechanical and comprises a pitch actuator (40) and a pair of control valves (120 and 210), a first of the valves (120) applying a metered fluid pressure from a governor controlled pilot valve to the actuator and blocking that signal and replacing it with a supply fluid pressure at the point of transition from governor to beta control. The second control valve (210) effects a controlled draining of the actuator and connection thereof with the power lever (305).

公开(公告)号：BR9007949A

公开(公告)日：1992-10-27

申请号：BR9007949

申请日：1990-12-05

Applicant: UNITED TECHNOLOGIES CORP

Inventor： DUCHESNEAU JEROME G ,  SCHWARTZ ROBERT A

IPC: B64C11/38

Abstract: A pitch control system has a main electronic control, a mechanical back-up control and a switching system for transferring pitch control from the electronic to the mechanical control in the event of electronic control failure. The switching system utilizes a switch for comparing the output of the electronic and mechanical control systems, the switch choosing the mechanical system if a failure occurs in the electronic control system. In certain failure modes, an enable solenoid simultaneously locks out the switch, to ensure mechanical pitch change control, and resets the mechanical back-up control to provide a lower degree of pitch control than conventional back-up controllers.

公开(公告)号：CA1227386A

公开(公告)日：1987-09-29

申请号：CA455760

申请日：1984-06-04

Applicant: UNITED TECHNOLOGIES CORP

Inventor： DUCHESNEAU JEROME G ,  SCHWARTZ ROBERT A

IPC: B64C11/38 ,  B64C11/40 ,  B64C11/42

Abstract: Engine Speed Control in Propeller Pitch Control Systems In a propeller pitch control system, a selector 10 isolates engine (42) speed control in one of two engine governor (175 and 300) systems. The selector is input with fluid pressure signals from a pair of pilot valves (215 and 325), each operated by a corresponding one of the governors. The selector passes the signal of lowest magnitude to an actuator 40 which sets blade pitch in accordance with the magnitude of the signal whereby the governor providing such signal (through its associated pilot valve) controls engine speed independently of the other governor.

公开(公告)号：CA1209559A

公开(公告)日：1986-08-12

申请号：CA443667

申请日：1983-12-19

Applicant: UNITED TECHNOLOGIES CORP

Inventor： SCHWARTZ ROBERT A ,  DUCHESNEAU JEROME G

IPC: B64C11/32 ,  B64C11/38 ,  B64C27/72

Abstract: Propeller Pitch Change Actuation System A propeller pitch change actuation system comprises an input actuator (230) driving a ball screw (200). operation of the ball screw rotates a torque tube (140) about the longitudinal axis thereof to drive a screw 145 and control valve 120 which controls the pressurization of pitch change actuator (87). Actuator (87) is supplied with hydraulic fluid through the interior of the torque tube.

公开(公告)号：BR9007947A

公开(公告)日：1992-10-06

申请号：BR9007947

申请日：1990-12-05

Applicant: UNITED TECHNOLOGIES CORP

Inventor： SCHWARTZ ROBERT A ,  CARVALHO PAUL A ,  LAMPETER ROBERT J

IPC: B64C11/38 ,  B64C11/30

Abstract: A pitch control system has a main electronic control, a mechanical back-up control and a switching system for transferring pitch control from the electronic to the mechanical control in the event of electronic control failure. The switching system utilizes a switch for comparing the output of the electronic and mechanical control systems, the switch choosing the mechanical system if a failure occurs in the electronic control system. By utilizing the switching system, a failure of the electronic control does not permit the blades to go to feather. In certain failure modes, an enable valve or an enable solenoid locks out the switch, to ensure mechanical pitch change control.

公开(公告)号：CA1246519A

公开(公告)日：1988-12-13

申请号：CA462199

申请日：1984-08-30

Applicant: UNITED TECHNOLOGIES CORP

Inventor： DUCHESNEAU JEROME G ,  SCHWARTZ ROBERT A

IPC: B63H3/10 ,  B64C11/40 ,  F02D29/02

Abstract: Pitch Control System For Variable Pitch Propeller A propeller pitch control system having a mechanical low pitch stop which includes an electrical backup therefor. The backup comprises an electrically operatable means (245) to effect blade pitch adjustment toward feather under conditions of failure of the low pitch stop indicated by propeller operation at pitch angles in the range of beta operation, but power settings in the range of normal engine speed governor pitch control. Such operating conditions actuate a pair of switches (190 and 195) connecting the means (245) to a voltage source to increase blade pitch toward feather, thereby preventing overspeed operation of the propeller.