Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
121 words
A power module of the resonant type comprising: a resonant power circuit for supplying current to a load; first and second switching elements coupled to the resonant circuit for alternately supplying current to the resonant circuit; trigger generator means coupled to the switching elements for supplying trigger signals to alternately enable the first and second switching elements; and control means coupled to the trigger generator means for operating the power module in a first mode wherein the resonant circuit current is controlled by varying the repetition rate of the trigger signals and in a second mode wherein the trigger signal repetition rate is fixed and the resonant circuit current is controlled by varying the on/off duty cycle of the power module.
Claim 2
Dependent Claim
121 words
A power module of the resonant type comprising: a resonant power circuit for supplying current to a load; first and second switching elements coupled to the resonant circuit for alternately supplying current to the resonant circuit; trigger generator means coupled to the switching elements for supplying trigger signals to alternately enable the first and second switching elements; and control means coupled to the trigger generator means for operating the power module in a first mode wherein the resonant circuit current is controlled by varying the repetition rate of the trigger signals and in a second mode wherein the trigger signal repetition rate is fixed and the resonant circuit current is controlled by varying the on/off duty cycle of the power module.
Claim 3
Dependent Claim
23 words
The power module as recited in claim 1 wherein the fixed trigger signal repetition rate is established as a lower repetition rate limit.
Claim 4
Dependent Claim
30 words
The power module as recited in claim 2 wherein the on/off duty cycle of the power module is established by modulating the trigger generator means with a low frequency waveform.
Claim 5
Dependent Claim
31 words
The power module as recited in claim 3 wherein the low frequency waveform is comprised of a modified sawtooth formed by the sum of a ramp waveform and a D.C. voltage.
Claim 6
Dependent Claim
22 words
The power module as recited in claim 2 wherein the power module is a battery charger and the load is a battery.
Claim 7
Dependent Claim
70 words
The battery charger as recited in claim 5 further including voltage sensing means for sensing the magnitude of the battery voltage wherein in the first mode of charger operation, the trigger signal repetition rate is increased in response to a sensed decrease in the battery voltage and the trigger signal repetition rate is decreased to the lower repetition rate limit in response to a sensed increased in the battery voltage.
Claim 8
Dependent Claim
38 words
The battery charger as recited in claim 6 wherein the charger operates in the second mode whenever the trigger signal repetition rate reaches the lower repetition rate limit and a further increase in the battery voltage is sensed.
Claim 9
Dependent Claim
24 words
The battery charger as recited in claim 7 wherein the lower trigger signal repetition rate limit is established at a frequency of 20 KHz.
Claim 10
Dependent Claim
29 words
The battery charger as recited in claim 8 wherein the on/off duty cycle of the charger is established by modulating the trigger generator means with a low frequency waveform.
Claim 11
Dependent Claim
30 words
The battery charger as recited in claim 9 wherein the low frequency waveform is comprised of a modified sawtooth formed by the sum of a waveform and a D.C. voltage.
Claim 12
Independent Claim
104 words
A method of controlling the current delivered to a load by a power module of the resonant type in which a pair of switching elements are alternately enabled by trigger signals to supply current to the resonant circuit comprising: varying the repetitive rate of the switching element trigger signals to control the current in the resonant circuit above a predetermined current level; and maintaining the switching element trigger repetition rate at the rate established by the predetermined current level and varying the on/off duty cycle of the power module to control the current in the resonant circuit at or below the predetermined current level.
Claim 13
Independent Claim
104 words
A method of controlling the current delivered to a load by a power module of the resonant type in which a pair of switching elements are alternately enabled by trigger signals to supply current to the resonant circuit comprising: varying the repetitive rate of the switching element trigger signals to control the current in the resonant circuit above a predetermined current level; and maintaining the switching element trigger repetition rate at the rate established by the predetermined current level and varying the on/off duty cycle of the power module to control the current in the resonant circuit at or below the predetermined current level.
Claim 14
Dependent Claim
22 words
The method as set forth in claim 11 wherein the power module is a battery charger and the load is a battery.