Injector driver control unit with internal overvoltage protection
First Claim
1. In an injector driver circuit for use with a fuel injector solenoid and a power source, said injector driver circuit comprising current sense means for sensing current flow through said injector solenoid and for providing a current sense signal in response thereto, injector drive control means for receiving an input signal and said current sense signal and for outputting a drive signal, and injector drive means responsive to said drive signal for selectively allowing current to flow from said power source through said injector solenoid and said injector drive means, an inprovement comprising:
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Accused Products
Abstract
An injector driver control unit with internal overvoltage protection. The device includes a first overvoltage sense unit (18) and an injector drive inhibit unit (21) for diverting injector drive signals from an injector drive unit (14) and for diverting flyback energy from a flyback control unit (16). The device also includes a second overvoltage sense unit (19) that can control a clamp control unit (22) to thereby activate an energy clamp (23) to control voltage potential across the injector solenoid (12).
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Citations
16 Claims
- 1. In an injector driver circuit for use with a fuel injector solenoid and a power source, said injector driver circuit comprising current sense means for sensing current flow through said injector solenoid and for providing a current sense signal in response thereto, injector drive control means for receiving an input signal and said current sense signal and for outputting a drive signal, and injector drive means responsive to said drive signal for selectively allowing current to flow from said power source through said injector solenoid and said injector drive means, an inprovement comprising:
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2. (a) first overvoltage sense means operably connected to said power source for detecting overvoltage conditions and for providing an overvoltage detected signal in response to detecting such an overvoltage condition;
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- 3. (b) injector drive inhibit means responsive to said overvoltage detected signal for inhibiting said drive signal from causing said injector drive means to allow current to flow from said power source through said injector solenoid and said injector drive means, such that injector solenoid current cannot flow through said injector drive means.
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14. In an injector driver circuit for use with a fuel injector solenoid and a power source, said injector driver circuit comprising current sense means for sensing current flow through said injector solenoid and for providing a current sense signal in response thereto, switching injector control means for receiving an input signal and said current sense signal and for outputting a drive signal, injector drive means responsive to said drive signal for selectively allowing current to flow from said power source through said injector solenoid and said injector drive means, and flyback control means operably connected to said injector solenoid for facilitating rapid dissipation of flyback energy from said injector solenoid, an improvement comprising:
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(a) first overvoltage sense means operably connected to said power source for detecting overvoltage conditions and for providing an overvoltage detected signal in response to detecting such an overvoltage condition; and (b) injector drive inhibit means responsive to said overvoltage detected signal for; (i) inhibiting said drive signal from causing said injector drive means to allow current to flow from said power source through said injector solenoid and said injector drive means, such that injector solenoid current cannot flow through said injector drive means; and (ii) providing a path from said flyback control means to ground to allow said flyback energy to be diverted to ground.
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Specification