Cold-start engine priming and air purging system
First Claim
1. A system for purging and priming an internal combustion engine which includes a carburetor having an air intake, said system comprising:
- pump means including a fuel line coupled through said carburetor to a fuel supply and responsive to an operator for selectively drawing fuel through said carburetor from said supply and thereby purging air from said fuel line and carburetor,means coupled by said fuel line to said pump means and positioned at said air intake for feeding fuel under pressure from said pump means into said air intake, andpriming control means including means responsive to pressure of fluid in said fuel line for distinguishing between pumping of air and pumping of fuel by pump means at said intake-positioned means, means coupled to said pressure-responsive means for timing duration of fuel pumping at said intake-positioned means, means for comparing said time duration to a time threshold, and means for indicating completion of a priming operation when said duration exceeds said threshold.
5 Assignments
0 Petitions
Accused Products
Abstract
A fuel delivery system for purging air from the reservoir of a diaphragm carburetor on an internal combustion engine and for supplying priming fuel to the carburetor air intake. An manual pump has an inlet coupled by a fuel line through the carburetor reservoir to a fuel supply, and an outlet connected by the fuel line to a constant flow rate nozzle orifice positioned at the carburetor air intake. A pressure switch is connected in the fuel line between the pump and orifice and provides a signal, in the form of a switch closure, to priming control circuitry whenever fuel, as distinguished from air, is pumped through the orifice to the carburetor air intake. The control circuitry receives battery power through the pressure switch contacts, and includes an integrator for accumulating total time of fuel flow and thereby indirectly indicating the total quantity of priming fuel supplied through the constant-flow orifice. When the integrated time duration exceeds a selected threshold, an LED is driven by an oscillator to advise the operator to terminate the manual priming operation. Most preferably, the time-duration threshold is varied as a function of engine temperature.
17 Citations
19 Claims
-
1. A system for purging and priming an internal combustion engine which includes a carburetor having an air intake, said system comprising:
-
pump means including a fuel line coupled through said carburetor to a fuel supply and responsive to an operator for selectively drawing fuel through said carburetor from said supply and thereby purging air from said fuel line and carburetor, means coupled by said fuel line to said pump means and positioned at said air intake for feeding fuel under pressure from said pump means into said air intake, and priming control means including means responsive to pressure of fluid in said fuel line for distinguishing between pumping of air and pumping of fuel by pump means at said intake-positioned means, means coupled to said pressure-responsive means for timing duration of fuel pumping at said intake-positioned means, means for comparing said time duration to a time threshold, and means for indicating completion of a priming operation when said duration exceeds said threshold. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11)
-
-
12. A system for purging and priming an internal combustion engine which includes a carburetor having an air intake, said system comprising:
-
pump means including a fuel pump and a fuel line coupling an inlet of said pump through said carburetor to a fuel supply, said pump being responsive to an operator for drawing fuel from said supply through said carburetor, simultaneously purging air from said carburetor and fuel line, and supplying fuel under pressure at a pump outlet, means including an orifice positioned at said air intake and coupled by said fuel line to said pump outlet for ejecting fuel under pressure at constant flow rate into said air intake, and means for measuring quantity of fuel ejected into said air intake to indicate completion of a priming operation, said quantity-measuring means comprising; a pressure switch connected to said fuel line between said pump outlet and said orifice and responsive to pressure fluid in said fuel line, an electronic timer responsive to said pressure switch for accumulating duration of time during which fuel is ejected at said constant flow rate into said air intake, and means for comparing accumulated time duration to a time threshold. - View Dependent Claims (13, 14, 15, 16, 17, 18, 19)
-
Specification