Motor drive apparatus
First Claim
1. A valve opening and closing control device making use of a rotational torque of a motor driven by a motor drive apparatus to control valve opening and closing of an internal combustion engine, the motor drive apparatus comprising an electric source;
- a bridge circuit comprising a plurality of rows of arms comprising two switching elements connected in series to each other and two diodes connected in parallel to corresponding switching elements, the respective arms being connected in parallel to the electric source, the motor having windings thereof connected to points of interconnection of the two switching elements on the respective arms, and control means for controlling ON/OFF of the switching elements, and wherein after putting the switching element on one of the two rows of arms in an ON state to carry an electric current to the windings, the control means causes an electricity introduction stoppage element that is one of the two switching elements put in ON state, to be put in an OFF state and causes the separate switching element on the same arm as that, on which the electricity introduction stoppage element is disposed, to be put in an ON state.
1 Assignment
0 Petitions
Accused Products
Abstract
There is provided a valve opening and closing control device (10, 110, 210, 300, 410) of a type making use of a motor (12, 320), in which device the driving performance of the motor is enhanced and heat generated by constituent elements is restricted. A bridge circuit (110, 212, 382, 411) of a motor driving circuit (100, 200, 370, 400) comprises three rows of arms (113u, 113v, 113w) comprising two switching elements (111a, 111b) connected in series to each other and two diodes (112a, 112b) connected in parallel to corresponding switching elements. The respective arms are connected in parallel to an electric source (120, 213, 383, 412), and motor windings (22u, 22w, 22v) are connected to points of interconnection of the switching elements on the respective arms. After putting the respective switching elements of the arms in an ON state to carry an electric current to the windings, a control circuit (130, 214, 385) causes the switching element in an ON state to be put as an electricity introduction stoppage element (111b) in an OFF state and causes the switching element of the same arm as that, on which the electricity introduction stoppage element is disposed, to be put in an ON state.
-
Citations
11 Claims
-
1. A valve opening and closing control device making use of a rotational torque of a motor driven by a motor drive apparatus to control valve opening and closing of an internal combustion engine, the motor drive apparatus comprising
an electric source; -
a bridge circuit comprising a plurality of rows of arms comprising two switching elements connected in series to each other and two diodes connected in parallel to corresponding switching elements, the respective arms being connected in parallel to the electric source, the motor having windings thereof connected to points of interconnection of the two switching elements on the respective arms, and control means for controlling ON/OFF of the switching elements, and wherein after putting the switching element on one of the two rows of arms in an ON state to carry an electric current to the windings, the control means causes an electricity introduction stoppage element that is one of the two switching elements put in ON state, to be put in an OFF state and causes the separate switching element on the same arm as that, on which the electricity introduction stoppage element is disposed, to be put in an ON state. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9)
-
-
10. A motor drive apparatus for controlling windings to thereby rotate an output shaft, the motor drive apparatus comprises:
-
a bridge circuit comprised of a plurality of arms respectively connected to the windings, wherein each of the plurality of arms comprises a plurality of switching elements connected together in series and a plurality of diodes respectively connected in parallel to the plurality of switching elements, wherein the plurality of arms are connected together at a first point having a first potential and at a second point having a second potential; and
a control circuit connected to the switching elements for sequentially switching the switching elements at a predetermined timing to thereby deliver electric current to the windings, wherein the predetermined timing substantially prevents all of the plurality of switching elements on one of the arms from being on at the same time. - View Dependent Claims (11)
-
Specification