Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
145 words
A circuit for controllably driving an A.C. motor, comprising, a regulatable D.C. voltage supply having a pulse modulation regulator, a smoothing circuit forming two supply lines following said regulator, means operating said regulator to maintain a desired voltage between said supply lines, an inverse rectifier having for each phase thereof a pair of controllable load switching elements in series between said supply lines, each of said load switching elements being bridged by a recovery diode, a motor phase connection between said elements of each said pair of elements, a braking circuit including two series connected brake switching elements between said supply lines, a brake resistor between the junction of said brake switching elements and one of said motor phase connections, and switching means responsive to the voltage between said intermediate circuit supply lines to control the frequency of said inverse rectifier and said braking circuit.
Claim 2
Dependent Claim
145 words
A circuit for controllably driving an A.C. motor, comprising, a regulatable D.C. voltage supply having a pulse modulation regulator, a smoothing circuit forming two supply lines following said regulator, means operating said regulator to maintain a desired voltage between said supply lines, an inverse rectifier having for each phase thereof a pair of controllable load switching elements in series between said supply lines, each of said load switching elements being bridged by a recovery diode, a motor phase connection between said elements of each said pair of elements, a braking circuit including two series connected brake switching elements between said supply lines, a brake resistor between the junction of said brake switching elements and one of said motor phase connections, and switching means responsive to the voltage between said intermediate circuit supply lines to control the frequency of said inverse rectifier and said braking circuit.
Claim 3
Dependent Claim
149 words
A circuit according to claim 1 including a mounting unit having supply and return rails forming said supply lines and a motor phase rail forming said motor phase connection, a plurality of mounting blocks connected to said mounting unit including a separate mounting block for each of said load switching elements and an associated one of said recovery diodes, said supply rail connecting the input sides of half of said load switching elements and said return rail connecting the output sides of the other half of said load switching elements, said motor phase rail connecting the junctions of all of said load switching elements, a separate mounting block for said two brake switching elements with the input side of one of said brake switching elements being connected to said supply rail and the output side of the other of said brake switching element being connected to said return rail.
Claim 4
Dependent Claim
39 words
A circuit according to claim 1 wherein said switching means triggers said brake switching elements respectively substantially simultaneously with said load switching elements of said pair of load switching elements associated with said brake switching elements through said resistor.
Claim 5
Dependent Claim
39 words
A circuit according to claim 1 wherein said switching means triggers said brake switching elements respectively slightly after triggering said load switching elements of said pair of load switching elements associated with said brake switching elements through said resistor.
Claim 6
Dependent Claim
33 words
A circuit according to claim 1 wherein said switching means generates control signals for brake switching elements which are trigger signals which are maintained for the entire desired periods of the conductive state.
Claim 7
Dependent Claim
22 words
A circuit according to claim 1 including extinguishing circuit means comprising extinguishing switching elements for separately extinguishing only said load switching elements.
Claim 8
Dependent Claim
26 words
A circuit according to claim 1 including a brake signal generator which responds when said D.C. voltage regulator switches from pulse modulation operation to blocking operation.