Model helicopter throttle governor/collective pitch control apparatus

An auto-collective pitch control apparatus for radio controlled model helicopters having an engine throttle servo for varying the rotational speed of the helicopter rotor and a collective pitch servo for varying the collective pitch of said rotor, said apparatus comprising:

• sensing means for periodically sensing changes in the model helicopter rotor speed in response to a first variation in rotor speed, including means for generating a timing signal corresponding to the sensed rotor speed;
• reference means responsive to said timing signal for providing a reference signal representing a first sensed rotor speed;
• comparison means coupled to said sensing means and said reference means for comparing said reference signal representing said first sensed rotor speed with said timing signal for a subsequently sensed rotor speed, including means for generating an error signal proportional to changes between said first and subsequently sensed rotor speeds;
• control signal means connected to said comparison means and responsive to said error signal for generating a control signal proportional to said error signal;
• and
• means for coupling said control signal to said collective pitch servo for proportionately varying said collective pitch in response to said first variation in rotor speed.

Control apparatus for radio controlled model helicopters having an engine throttle servo for varying the rotational speed of the helicopter rotor and a collective pitch servo for varying the collective pitch of said rotor, said apparatus comprising:

• sensing means for periodically sensing changes in the model helicopter rotor speed in response to a first variation in rotor speed or collective pitch, including means for generating a timing signal corresponding to the sensed rotor speed;
• said sensing means including,
• a series of magnetic members mounted equidistantly around said model helicopter rotor for rotation therewith;
• a magnetic transducer element rigidly mounted in position immediately adjacent said series of magnetic members for detecting the movement of each of said members adjacent said transducer element during rotation of said rotor;
• and
• a first monostable multivibrator coupled to said magnetic transducer element, said first monostable multivibrator triggered ON by the detected movement of said members;
• reference means responsive to said timing signal for providing a reference signal representing a first sensed rotor speed;
• comparison means coupled to said sensing means and said reference means for comparing said reference signal representing said first sensed rotor speed with said timing signal for a subsequently sensed rotor speed, including means for generating an error signal proportional to changes between said first and subsequently sensed rotor speeds;
• control signal means connected to said comparison means and responsive to said error signal for generating a control signal proportional to said error signal;
• and
• means for coupling said control signal to a respective one of said servos for proportionately varying either said rotor speed for said collective pitch in response to said first variation.

In radio controlled model helicopter apparatus including a model helicopter, a helicopter rotor, an engine for rotating said rotor, a throttle servo connected to said engine for varying the model helicopter rotor speed function, a collective pitch servo coupled to said rotor for varying the rotor collective pitch function, and a radio receiver for receiving a radio transmitter signal for manually controlling one of said helicopter functions from said radio transmitter, the improvement comprising:

• sensing means for periodically sensing changes in the model helicopter rotor speed in response to a manual variation in one of said helicopter functions, including means for generating a timing signal corresponding to the sensed rotor speed;
• reference means responsive to said timing signal for providing a reference signal representing a first sensed rotor speed;
• comparison means coupled to said sensing means and said reference means for comparing said reference signal representing said first sensed rotor speed with said timing signal for subsequently sensed rotor speed, including means for generating an error signal proportional to changes between said first and subsequently sensed rotor speeds;
• control signal means connected to said comparison means and responsive to said error signal for generating a control signal proportional to said error signal;
• and
• means for coupling said control signal to the other of said servos for varying the respective other of said helicopter functions in response to said manual variation of said first helicopter function, including means for coupling said control signal to said throttle servo for maintaining said rotor speed substantially constant in response to manual variations in collective pitch.

In radio controlled model helicopter apparatus including a model helicopter, a helicopter rotor, an engine for rotating said rotor, a throttle servo connected to said engine for varying the model helicopter rotor speed function, a collective pitch servo coupled to said rotor for varying the rotor collective pitch function, and a radio receiver for receiving a radio transmitter signal for manually controlling one of said helicopter functions from said radio transmitter, the improvement comprising:

• sensing means for periodically sensing changes in the model helicopter rotor speed in response to a manual variation in one of said helicopter functions, including means for generating a timing signal corresponding to the sensed rotor speed;
• reference means responsive to said timing signal for providing a reference signal representing a first sensed rotor speed;
• comparison means coupled to said sensing means and said reference means for comparing said reference signal representing said first sensed rotor speed with said timing signal for subsequently sensed rotor speed, including means for generating an error signal proportional to changes between said first and subsequently sensed rotor speeds;
• control signal means connected to said comparison means and responsive to said error signal for generating a control signal proportional to said error signal;
• and
• means for coupling said control signal to the other of said servos for varying the respective other of said helicopter functions in responsive to said manual variation of said first helicopter function including means for coupling said control signal to said collective pitch servo for proportionally varying said collective pitch in response to manual variations in rotor speed.