Frequency modulation transfer system and method

A system for transferring the operation of an electrically controllable mechanism from one to the other of two control signals,

• means to generate a first control signal,
• means to generate a second control signal,
• an electrically controllable mechanism responsive to either the first or second control signal,
• switching means when in one condition to conduct the first control signal only to the mechanism, and when in the other condition to conduct the second control signal only to the mechanism,
• means to operate the switching means to its other condition repetitively at an increasing frequency to a predetermined maximum frequency at times when the switching means is controlled by the first control signal,
• means to operate the switching means to its one condition repetitively at an increasing frequency to a predetermined maximum frequency at times when the switching means is controlled by the second control signal, and
• means to operate the switching means to the opposite condition at a decreasing frequency at times when the switching means is operated to either the one condition or the other condition at the maximum predetermined frequency.

A system for transferring the operation of an electrically controllable mechanism from a first control signal to a second control signal,

• means to generate a first control signal,
• means to generate a second control signal,
• an electrically controllable mechanism normally connected electrically to the first signal operating means to respond to the first control signal,
• switching means operable to connect and disconnect substantially simultaneously the second and first control signals respectively, and
• means to operate the switching means first to connect and disconnect the second and first respective control signals repetitively at an increasing frequency to a predetermined maximum frequency and then to connect and disconnect the first and second control signals repetitively at a decreasing frequency whereby the switching means ultimately connects electrically the second signal generating means to the electrically operable mechanism.

A method of transferring the operation of an electrically controllable mechanism from one to the other of two control signals having a first and second amplitude level comprising

• controlling the mechanism in accordance with the first amplitude level of the one control signal,
• switching the control signal to the second amplitude level repetitively at an increasing rate until a predetermined maximum frequency,
• switching the control signal to the first amplitude level repetitively at a decreasing rate until the mechanism is controlled at the second amplitude level, and
• filtering the first and second occurring amplitude signals during the switching at the increasing and decreasing frequency, whereby the mechanism is controlled by a filtered control signal having an amplitude that gradually changes from the first to the second amplitude during the transfer period.