Abstract A servosystem having solid-state components includes means for summing an alternating command signal with a motor shaft position signal and when the resulting difference signal exceeds a predetermined threshold drivers are actuated for applying to the motor a voltage having a polarity in accordance with the phase of the difference signal relative to a reference. The voltage is cut off when the motor is at null, whereupon inertia drives the motor past null to provide a difference signal of opposite polarity so that the motor is driven in the opposite direction until it again passes through null, reversing the voltage thereto with the result being that full voltage is applied to the motor until the null is reached.
A servosystem, comprising: a servomotor; means connected to the servomotor for pRoviding a motor shaft position signal; means for providing a command signal; means connected to the shaft position signal means and to the command signal means for summing the signals therefrom and providing a difference signal; a voltage source; switching means connecting the voltage source to the servomotor; driving means connected to the switching means; means for connecting the driving means to the difference signal means, with the driving means responsive to the difference signal above a predetermined level in one sense for rendering the switching means effective to apply voltage from the voltage source to the motor; means for providing an AC reference signal; the means for connecting the difference signal means to the driving means being connected to the reference signal means for providing a first signal when the difference signal is of one phase relative to the reference signal and for providing a second signal when said difference sIgnal is of another phase; the driving means including means responsive to the first signal for providing a signal for driving the motor in one direction and responsive to the second signal for providing a signal for driving the motor in an opposite direction; means connected to the means for providing the motor driving signals for summing the signals therefrom and for providing a signal corresponding to the difference therebetween; means connected to the difference signal for filtering said signal; means for providing a reference signal; means for comparing the reference signal and the filtered signal to provide a triggering signal when the difference between the compared signals exceeds a predetermined level; and braking means connected to the triggering signal means and to the motor for braking the motor in response to the triggering signal.
Claim 2
Dependent Claim
297 words
A servosystem, comprising: a servomotor; means connected to the servomotor for pRoviding a motor shaft position signal; means for providing a command signal; means connected to the shaft position signal means and to the command signal means for summing the signals therefrom and providing a difference signal; a voltage source; switching means connecting the voltage source to the servomotor; driving means connected to the switching means; means for connecting the driving means to the difference signal means, with the driving means responsive to the difference signal above a predetermined level in one sense for rendering the switching means effective to apply voltage from the voltage source to the motor; means for providing an AC reference signal; the means for connecting the difference signal means to the driving means being connected to the reference signal means for providing a first signal when the difference signal is of one phase relative to the reference signal and for providing a second signal when said difference sIgnal is of another phase; the driving means including means responsive to the first signal for providing a signal for driving the motor in one direction and responsive to the second signal for providing a signal for driving the motor in an opposite direction; means connected to the means for providing the motor driving signals for summing the signals therefrom and for providing a signal corresponding to the difference therebetween; means connected to the difference signal for filtering said signal; means for providing a reference signal; means for comparing the reference signal and the filtered signal to provide a triggering signal when the difference between the compared signals exceeds a predetermined level; and braking means connected to the triggering signal means and to the motor for braking the motor in response to the triggering signal.
Claim 3
Dependent Claim
65 words
A system as described by claim 1, wherein: the voltage source provides voltages of opposite polarities; and the switching means is affected by the signal for driving the motor in the one direction for applying voltage of one polarity to the motor, and is affected by the signal for driving the motor in the opposite direction for applying voltage of opposite polarity to the motor.