Elevator active suspension system

Apparatus for stabilizing a cab suspended in an elevator car frame in a hoistway, comprising:

• sensor means, responsive to a magnitude and phase of a selected parameter associated with said suspended cab, for providing a sensed signal indicative thereof;
• control means, responsive to said sensed signal, for providing a control signal having a magnitude and phase selected according to said magnitude and phase of said selected parameter;
• and
• actuator means, responsive to said control signal, for actuating said suspended cab, wherein said control means comprises means responsive to said sensed signal for providing a command signal and further comprises means responsive to a sensed signal indicative of a response of said cab to said actuator means for comparison to said command signal.

Apparatus for stabilizing a cab suspended in an elevator car frame in a hoistway, comprising:

• sensor means, responsive to a magnitude and phase of a selected parameter associated with said suspended cab, for providing a sensed signal indicative thereof;
• control means, responsive to said sensed signal, for providing a control signal having a magnitude and phase selected according to said magnitude and phase of said selected parameter;
• and
• actuator means, responsive to said control signal, for actuating said suspended cab, wherein said control means provides a force command signal in response to said sensed signal and further comprises comparator means for comparing the magnitude of said force command signal to the magnitude of a force feedback signal and wherein said control signal is proportional to an error signal having a magnitude indicative of a difference between said magnitudes of said force command signal and said force feedback signal.

A method for stabilizing a cab suspended in an elevator car frame in a hoistway, comprising the steps of:

• sensing a selected parameter associated with the suspended cab and providing a sensed signal indicative thereof;
• providing a control signal comprising a summation of signal components of said sensed signal, each component signal increased or decreased and shifted in phase according to a function of gain and phase shift versus component signal frequency;
• actuating said suspended cab in response to said control signal, and wherein said step of sensing comprises the step of sensing translational movement of the cab by providing said sensed signal as three sensed signals indicative thereof for providing said control signal as one or more control signals required to counteract movements indicated by said sensed signals, and
• wherein two of said three sensed signals are indicative of translational movement of the cab along lines situated on opposite sides of the cab centerline and parallel to a signal selected axis and wherein a single sensed signal is indicative of translational movement along an axis perpendicular to said single selected axis.

Apparatus for stabilizing a cab suspended in an elevator car frame in a hoistway, comprising:

• sensor means, responsive to a magnitude and phase of a selected parameter associated with said suspended cab, for providing a sensed signal indicative thereof;
• control means, responsive to said sensed signal, for providing a control signal having a magnitude and phase selected according to said magnitude and phase of said selected parameter;
• and
• actuator means, responsive to said control signal, for actuating said suspended cab, wherein said magnitude of said control signal is selected according to a compensation function having negative gain (dB) or less than unity gain below a first selected frequency .omega..sub.1 and also above a second selected frequency .omega..sub.2 and positive gain (dB) or gain greater than unity in between .omega..sub.1 and .omega..sub.2.

A method for stabilizing a cab suspended in an elevator car frame in a hoistway, comprising the steps of:

• sensing a selected parameter associated with the suspended cab and providing a sensed signal indicative thereof;
• providing a control signal comprising a summation of signal components of said sensed signal, each component signal increased or decreased and shifted in phase according to a function of gain and phase shift versus component signal frequency the magnitude of said control signal is selected according to a compensation function having negative gain (dB) or less then unity gain below a first selected frequency w.sub.1 and above a second selected frequency w.sub.2 and a positive or greater then unity in between;
• and
• actuating said suspended cab in response to said control signal.

Apparatus for horizontally stabilizing an elevator car, comprising:

• sensor means, responsive to acceleration of said car, for providing a sensed signal indicative thereof comprising component signals having differing magnitudes at differing frequencies;
• compensation means, responsive to said sensed signal, for providing a control signal having a magnitude comprising a summation of said component signals each increased or decreased according to a function of gain and phase shift versus component frequency which function provides maximum gain and minimum phase shift in a central region of a selected range of frequencies;
• and
• actuator means, responsive to said control signal, for actuating said car.