Digital control system for electromagnetic clutch

A controller for supplying electrical current to a coil of an electromagnetic clutch driven by an engine to regulate the engagement thereof comprising:

• means for storing a plurality of clutch current engagement curves;
• means for generating a signal when it is desired to engage the clutch;
• means for generating a signal which is representative of the vacuum level generated by the engine;
• and
• control means responsive to said engagement signal and said engine vacuum level signal for selecting one of said stored clutch current engagement curves and for supplying electrical current to the coil of the clutch in accordance therewith.

A controller for supplying electrical current to a coil of an electromagnetic clutch mounted in a vehicle to regulate the engagement thereof comprising:

• means for storing a plurality of clutch current engagement curves;
• means for generating a signal when it is desired to engage the clutch;
• means for generating a signal which is representative of the relative angle at which the vehicle is being operated;
• and
• control means responsive to said engagement signal and said vehicle angle signal for selecting one of said stored clutch current engagement curves and for supplying electrical current to the coil of the clutch in accordance therewith.

A controller for supplying electrical current to a coil of an electromagnetic clutch to regulate the engagement thereof comprising:

• means for storing a plurality of clutch current engagement curves;
• means for generating a signal when it is desired to engage the clutch;
• means for generating signals which are representative of a plurality of operating conditions of the clutch;
• and
• control means for sequentially sampling each of said operating condition signals, said control means being responsive to said engagement signal and each of said operating condition signals for selecting one of said stored clutch current engagement curves and for supplying electrical current to the coil of the clutch in accordance therewith.

A controller for supplying electrical current to a coil of an electromagnetic clutch having an armature which is movable between engaged and disengaged positions to regulate the engagement thereof comprising:

• means for storing a plurality of clutch current engagement curves;
• means for generating a signal when it is desired to engage the clutch;
• means for generating a signal which is representative of the magnitude of the electrical current passing through the coil of the clutch;
• and
• control means responsive to said engagement signal and a decrease in the magnitude of the electrical current passing through the coil of the clutch caused by the initial movement of the armature from said disengaged position to said engaged position for selecting one of said stored clutch current engagement curves and for supplying electrical current to the coil of the clutch in accordance therewith.

A controller for supplying electrical current to a coil of an electromagnetic clutch to regulate the engagement thereof comprising:

• means for storing a plurality of clutch current engagement curves;
• means for generating a signal when it is desired to engage the clutch;
• means for generating a signal which is representative of an operating condition of the clutch;
• and
• control means responsive to said engagement signal and said operating condition signal for selecting one of said stored clutch current engagement curves and for supplying electrical current to the coil of the clutch in accordance therewith and for interrupting the supply of electrical current to the coil of the clutch when an abnormal condition is sensed.