Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
230 words
An actuator driving circuit for driving an actuator employed in a servocontrol system, the circuit comprising: an error signal input terminal to which an error signal obtained in the servocontrol system is supplied, amplifying means for amplifying the error signal supplied through said error signal input terminal to produce a driving signal and for supplying said driving signal to the actuator, power supply voltage source means for producing a first power supply voltage and a second power supply voltage higher than said first power supply voltage, power supply voltage selecting means for selecting one of the first and second power supply voltages so as to supply said amplifying means with said one of the first and second power supply voltages selected, and level detecting means for detecting a specific portion of the error signal having such a level as to cause said amplifying means to produce a portion of the driving signal having a level limited to be constant under a condition in which said first power supply voltage is supplied to said amplifying means and for producing a detection output by which said power supply voltage selecting means is controlled to select said second power supply voltage in place of said first power supply voltage when said specific portion of the error signal is detected, thereby enabling the circuit to compensate for shocks and vibrations caused by external force.
Claim 2
Dependent Claim
230 words
An actuator driving circuit for driving an actuator employed in a servocontrol system, the circuit comprising: an error signal input terminal to which an error signal obtained in the servocontrol system is supplied, amplifying means for amplifying the error signal supplied through said error signal input terminal to produce a driving signal and for supplying said driving signal to the actuator, power supply voltage source means for producing a first power supply voltage and a second power supply voltage higher than said first power supply voltage, power supply voltage selecting means for selecting one of the first and second power supply voltages so as to supply said amplifying means with said one of the first and second power supply voltages selected, and level detecting means for detecting a specific portion of the error signal having such a level as to cause said amplifying means to produce a portion of the driving signal having a level limited to be constant under a condition in which said first power supply voltage is supplied to said amplifying means and for producing a detection output by which said power supply voltage selecting means is controlled to select said second power supply voltage in place of said first power supply voltage when said specific portion of the error signal is detected, thereby enabling the circuit to compensate for shocks and vibrations caused by external force.
Claim 3
Dependent Claim
36 words
An actuator driving circuit according to claim 1, wherein said amplifying means comprises an operational amplifier having a pair of input terminals, one of said pair of input terminals being supplied with the tracking error signal.
Claim 4
Dependent Claim
73 words
An actuator driving circuit according to claim 2, wherein said level detecting means is connected to said pair of input terminals of the operational amplifier so as to detect a level of a voltage difference between said pair of input terminals and is further connected to said power supply voltage selecting means so as to supply said power supply voltage selecting means with a detection output of the level of said voltage difference.
Claim 5
Dependent Claim
97 words
An actuator driving circuit according to claim 3, wherein said level detecting means comprises a first level comparator for comparing a voltage level at one of said pair of input terminals with a voltage level at the other of said pair of input terminals and a second comparator for comparing the voltage level at said other of said pair of input terminals with the voltage level at said one of said pair of input terminals and an output terminal of each of said first and second level comparators is connected to said power supply voltage selecting means.
Claim 6
Dependent Claim
48 words
An actuator driving circuit according to claim 3, wherein said level detecting means is connected directly to one of said pair of input terminals of the operational amplifier and connected through threshold level generating means to the other of said pair of input terminals of the operational amplifier.
Claim 7
Dependent Claim
36 words
An actuator driving circuit according to claim 2, wherein said amplifying means further comprises a pair of power amplifying transistors having respective collectoremitter paths connected in series with a connection point therebetween coupled with said actuator.
Claim 8
Dependent Claim
38 words
An actuator driving circuit according to claim 6, wherein said pair of power amplifying transistors are connected to said power supply voltage selecting means so as to be supplied with said first and second power supply voltages selectively.
Claim 9
Dependent Claim
73 words
An actuator driving circuit according to claim 7, wherein said level detecting means is connected to said pair of input terminals of the operational amplifier so as to detect a level of a voltage difference between said pair of input terminals and is further connected to said power supply voltage selecting means so as to supply said power supply voltage selecting means with a detection output of the level of said voltage difference.
Claim 10
Dependent Claim
53 words
An actuator driving circuit according to claim 1, wherein said power supply voltage selecting means comprises a switching device controlled by the detection output obtained from said level detecting means to be made conductive for selecting the second power supply voltage and supplying said amplifying means with said second power supply voltage selected.