The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 05, 1981
Filed:
Jun. 20, 1979
Werner Jundt, Ludwigsburg, DE;
Herman Roozenbeek, Schwieberdingen, DE;
Robert Bosch GmbH, Stuttgart, DE;
Abstract
The closure angle of an interrupter switch connected in series with the primary winding of an ignition coil is varied as a predetermined function of engine speed by charging and discharging of an integrator circuit which in turn changes the cut-in threshold of a threshold circuit controlling the operation of the interrupter switch. When the spark repetition rate becomes sufficiently high for residual energy to be stored in the coil when the interrupter switch closes, this type of control results in an undesired decrease of closure angle. Therefore, in the present system, the operation of the charging circuit for the integrator circuit is always delayed until the current through the primary winding reaches a predetermined minimum value exceeding the maximum possible residual current in the primary winding when the interrupter switch first closes. The charging circuit thus always operates from the same initial condition, preventing undesired changes in the closure angle at high speeds.