Feeding device for direct current motor

Claim 2

A feeding device for a motor with D. C. current, comprising, on the one hand, at least two control arrangements for the passage of an electric current installed on either side of said motor to form a link of the circuit connected with the terminals of a D. C. power source, said arrangements each including at least one power transistor and, on the other hand, an actuating device, as such controlled by a control signal, to simultaneously render said arrangements conductive or blocking, said actuating device comprises two transitors of which, the first, receiving the control signal at its base, controls by its emitter-collector path, on the one hand, one of said arrangements apt to be rendered partially conductive by controlling the conduction of its power transistors as a function of said control signal, and on the other hand, the base of the second transistor which is saturated and whose emitter-collector path controls the second arrangement capable of becoming totally conductive by saturating its power transistors, irrespective of the amplitude of the control signal.

Claim 3

A device according to claim 1, characterized by each control arrangement for the passage of an electric current including two power transistors of the same polarity, mounted in a Darlington connection the power transistors of the arrangement apt to be rendered partially conductive being sturdy-breakdown voltage transistors.

Claim 4

A device according to claim 1, including, in addition to the two aforementioned first control arrangements, two second arrangements for the passage of an electric current, each comprising at least a power transistor forming with the first ones a bridge whose one diagonal is linked to the terminals of the pWer source, and the other to the terminals of said motor, characterized in that it comprises a second actuating device which is controlled by a blocking signal, other than the control signal, and which includes two transistors of which the first receiving the braking signal at its base, controls by its emitter-collector path, on the one hand, the one of the second arrangements apt to become partially conductive and on the other hand, the second transistor which is saturated and whose emitter-collector path controls the one of the second arrangements capable of being rendered totally conductive.

Claim 5

A device according to claim 3, characterized in that said one of the second arrangements which was rendered partially conductive consists of a Darlington connection of two power transistors of the same polarity.

Claim 6

A device according to claim 3, characterized by including means for imparting a predetermined threshhold voltage, at the terminals of said second arrangement which was rendered completely conductive.

Claim 7

A device according to claim 5, characterized by said second driving device controlling the second arrangement which is partially conductive by means of a transistor type circuit breaker which, when it closes, imposes a fixed potential on the connection point between this arrangement and said motor.

Claim 8

A device according to claim 6, characterized by the fixed potential being obtained by means of at least one Zener diode

Claim 9

A device according to claim 7, characterized in that said transistor type circuit breaker includes a transistor whose base and emitter are controlled by the second driving device, said emitter being stabilized at its potential by said Zener diode, while the emitter-collector path of this transistor controls the second arrangement made totally conductive, which comprises two transistors of opposite polarities such that the emitter and the collector of the one are linked to the collector and to the base of the other, respectively.

Claim 10

In a motor drive system including a D. C. motor, a D. C. power source and a pair of power transistor means for selectively connecting said motor across said source, said motor being connected in series between said power transistor means, the improvement which comprises: control means for selectively actuating one of said power transistor means from cut off condition to saturated condition while the other power transistor means is actuated from cut off condition to partially conductive condition, whereby said one power transistor means may be constituted as a relatively inexpensive component while only said other power transistor means is required to be constituted as a high performance relatively expensive component, said control means including a control signal input, first means connected to said control signal input and to said other power transistor means for causing conduction of said other power transistor means in accord with the amplitude of a control signal, and second means connected to said first means and to said one power transistor means for causing saturation of said one power transistor means in response to but independently of amplitude of said control signal.

Claim 11

In a motor drive system including a D. C. motor, a D. C. power source and a pair of power transistor means for selectively connecting said motor across said source, said motor being connected in series between said power transistor means, the improvement which comprises: control means for selectively actuating one of said power transistor means from cut off condition to saturated condition while the other power transistor means is actuated from cut off condition to partially conductive condition, whereby said one power transistor means may be constituted as a relatively inexpensive component while only said other power transistor means is required to be constituted as a high performance relatively expensive component, said control means including a control signal input, first means connected to said control signal input and to said other power transistor means for causing conduction of said other power transistor means in accord with the amplitude of a control signal, and second means connected to said first means and to said one power transistor means for causing saturation of said one power transistor means in response to but independently of amplitude of said control signal.

Claim 12

In a reversible motor drive system, the combination of: a D. C. motor and a D. C. power source; a bridge circuit connected to said motor and said source selectively to energize said motor in forward and reverse senses, said bridge circuit having four legs each formed as a power transistor means; first control means connected to a first pair of legs of said bridge circuit for energizing said motor in the forward sense; and second control means connected to a second pair of legs of said bridge circuit for energizing said motor in the reverse sense; said first control means having a control signal input and being connected to the power transistors constituting said first pair of legs simultaneously to drive one of them into saturation in response to the presence of but irrespective of amplitude of a control signal input while causing conduction of the other leg in dependence upon said amplitude.

Claim 13

In a reversible motor drive system, the combination of: a D. C. motor and a D. C. power source; a bridge circuit connected to said motor and said source selectively to energize said motor in forward and reverse senses, said bridge circuit having four legs each formed as a power transistor means; first control means connected to a first pair of legs of said bridge circuit for energizing said motor in the forward sense; and second control means connected to a second pair of legs of said bridge circuit for energizing said motor in the reverse sense; said first control means having a control signal input and being connected to the power transistors constituting said first pair of legs simultaneously to drive one of them into saturation in response to the presence of but irrespective of amplitude of a control signal input while causing conduction of the other leg in dependence upon said amplitude.