Abstract: A control system for a low cost, light duty combustion engine, where the control system generally utilizes an engine speed input signal and independent operating sequences to determine a desired ignition timing. There are several independent operating sequences, each one of which is designed to optimally control the engine under certain conditions. These operating sequences include a Cranking sequence, a Warm Up sequence, a Normal Mode sequence, an Acceleration sequence, a Come Down sequence, a Recovery Bump sequence, and a Part Throttle sequence. During idling conditions, the Normal Mode sequence uses rapid changes in the ignition timing to maintain the engine speed in a small, idle engine speed range. By utilizing these operational sequences, the control system improves the performance of a low cost, light duty engine across a wide array of conditions.

Abstract: A carburetor has an air intake passage, a fuel passage, a fuel nozzle in communication with the fuel passage and having an opening through which fuel flows, a first valve in communication with the air intake passage and being movable between first and second positions, and a second valve in communication with the fuel nozzle and also being movable between first and second positions to vary the effective flow area of the fuel nozzle. The fuel nozzle is preferably carried by a tube fitted sealably in a bore being in communication with the fuel passage. The opening is defined by the tube and is preferably elongated, extending axially with respect to the tube. A needle of the second valve moves axially within the tube to variably obstruct the opening to control fuel flow. Preferably, a method of manufacturing the tube utilizes a circular cutting tool which plunges into the tube cutting a slit as the opening having a sharp peripheral edge for atomizing the fuel.

Abstract: An engine carburetor and a solenoid valve assembly therefor and methods of assembling the same. The carburetor has a body with a fuel and air mixing passage communicating with an air bleed passage. A cavity extends into the body for communication with the air bleed passage. A solenoid housing is received in the cavity and maintains a coil body for receipt of a valve body therein. The valve body moves between a retracted position to substantially open the air bleed passage and an extended position to substantially close the air bleed passage.

Abstract: A priming and purging system and method for an internal combustion engine having a diaphragm carburetor includes a pump in fluid communication with the carburetor, a portion of the engine, and a fuel tank. The pump is manually actuatable to draw liquid fuel and any fuel vapors and gases from the carburetor and to deliver at least some liquid fuel into a portion of the engine to prime the engine and liquid fuel and any fuel vapor and gases toward and preferably into the fuel tank to facilitate purging the carburetor.

Abstract: A control system for a low cost, light duty combustion engine, where the control system generally utilizes an engine speed input signal and independent operating sequences to determine a desired ignition timing. There are several independent operating sequences, each one of which is designed to optimally control the engine under certain conditions. These operating sequences include a Cranking sequence, a Warm Up sequence, a Normal Mode sequence, an Acceleration sequence, a Come Down sequence, a Recovery Bump sequence, and a Part Throttle sequence. During idling conditions, the Normal Mode sequence uses rapid changes in the ignition timing to maintain the engine speed in a small, idle engine speed range. By utilizing these operational sequences, the control system improves the performance of a low cost, light duty engine across a wide array of conditions.

Abstract: A carburetor has an air intake passage, a fuel passage, a fuel nozzle in communication with the fuel passage and having an opening through which fuel flows, a first valve in communication with the air intake passage and being moveable between first and second positions, and a second valve in communication with the fuel nozzle and also being movable between first and second positions to vary the effective flow area of the fuel nozzle.

Abstract: A fuel needle valve assembly of a carburetor has a retainer which yieldingly restrains the rotational fuel flow setting capability of the needle valve. The retainer engages a shank of the needle valve and a parallel shaft, both of which project from the carburetor body. The retainer exerts a force which laterally displaces the projecting shank with respect to the shaft. The retainer has sufficient strength to ensure the factory set rotational setting of the fuel needle valve does not alter when a limiter cap is press fitted to a distal head of the needle. Furthermore, wherein the shaft is also a shank of a second needle valve, the same retainer laterally displaces the projecting shanks of both needle valves.

Abstract: A carburetor preferably of a diaphragm type for an internal combustion engine has a low speed circuit for starting and idling of a cold engine. An air bleed line of the low speed circuit communicates between an inlet of a fuel and air mixing passage of the carburetor and an emulsifying chamber of the low speed circuit. Fuel flows to the emulsifying chamber from a fuel metering chamber and is regulated by a low speed idling adjustment needle screw. The bleed air and the fuel mixes within the emulsifying chamber and flows into the mixing passage between the throttle valve and the outlet of the mixing passage. Promoting this flow is a high vacuum produced by cranking and idling of the engine and accentuated by the substantially closed throttle valve. The fuel-and-air mixture is rich during cold idling as a result of the closed air bleed line. When the engine warms up, the air bleed line is opened via the restrictor valve.

Abstract: A carburetor preferably of a diaphragm type for an internal combustion engine has a low speed circuit for starting and idling of a cold engine. An air bleed line of the low speed circuit communicates between an inlet of a fuel and air mixing passage of the carburetor and an emulsifying chamber of the low speed circuit. Fuel flows to the emulsifying chamber from a fuel metering chamber and is regulated by a low speed idling adjustment needle screw. The bleed air and the fuel mixes within the emulsifying chamber and flows into the mixing passage between the throttle valve and the outlet of the mixing passage. Promoting this flow is a high vacuum produced by cranking and idling of the engine and accentuated by the substantially closed throttle valve. The fuel-and-air mixture is rich during cold idling as a result of the closed air bleed line. When the engine warms up, the air bleed line is opened via the restrictor valve.

Abstract: The present invention relates to microbial processes for carrying out the asymmetric reduction of a ketone to an alcohol, which comprises: contacting the ketone with a microorganism, or an enzyme reduction system capable of accomplishing the subject reduction comprising an enzyme derived from said microorganism and a co-factor for said enzyme, and incubating the resulting mixture under conditions sufficient to yield more of the desired (R)-enantiomer of the corresponding alcohol than the undesired (S)-enantiomer. The chiral (R)-enantiomer can be used in the synthesis of certain &bgr;-adrenergic receptor agonists.

Abstract: A fuel needle valve assembly of a carburetor has a retainer which yieldingly restrains the rotational fuel flow setting capability of the needle valve. The retainer engages a shank of the needle valve and a parallel shaft, both of which project from the carburetor body. The retainer exerts a force which laterally displaces the projecting shank with respect to the shaft. The retainer has sufficient strength to ensure the factory set rotational setting of the fuel needle valve does not alter when a limiter cap is press fitted to a distal head of the needle. Furthermore, wherein the shaft is also a shank of a second needle valve, the same retainer laterally displaces the projecting shanks of both needle valves.

Abstract: A fuel needle valve assembly of a carburetor has a retainer which yieldingly restrains the rotational fuel flow setting capability of the needle valve. The retainer engages a shank of the needle valve and a parallel shaft, both of which project from the carburetor body. The retainer exerts a force which laterally displaces the projecting shank with respect to the shaft. The retainer has sufficient strength to ensure the factory set rotational setting of the fuel needle valve does not alter when a limiter cap is press fitted to a distal head of the needle. Furthermore, wherein the shaft is also a shank of a second needle valve, the same retainer laterally displaces the projecting shanks of both needle valves.

Abstract: The present invention relates to processes for the microbial oxidation of 2-methylquinoxaline to 2-quinoxalinecarboxylic acid which comprise contacting 2-methylquinoxaline with a microorganism, or a suitable mutant thereof, and incubating the resulting mixture under conditions sufficient to yield an amount of said 2-quinoxalinecarboxylic acid. The present processes optionally further comprise the isolation and purification of 2-quinoxalinecarboxylic acid.

Abstract: A single needle diaphragm type carburetor has a throttle valve in a mixing passage with a venturi, an idle fuel nozzle downstream of the throttle valve when in its idle position, a high speed fuel nozzle preferably disposed within the venturi upstream of the throttle valve and a supplemental air bleed passage opening into the mixing passage upstream of both the idle and high speed fuel nozzles. Both the idle and high speed fuel nozzles communicate with each other through a transfer passage and are fed from the same fuel circuit controlled by a single needle valve which limits the fuel flow to them. At idle or low speed and low load engine operation air supplied by the supplemental air bleed passage is mixed with fuel supplied to the idle fuel nozzle. At wide open throttle, air from the air bleed passage is routed near the idle fuel nozzle, and mixed with the fuel supplied to the high speed nozzle.

Abstract: A safety dead-bolt lock adapted to be mounted on a door. The safety dead-bolt lock has a bolt and a rotatable bolt activator. A safety knob is adapted to rotate the bolt activator and thus extend and withdraw the bolt. The safety knob has a rotatable member engaged with the bolt activator and a stationary member adapted to be fixed to the door. A disengageable interlocking mechanism is adapted to prevent rotation of the rotatable member relative to the stationary member. Depressable tabs mounted in the rotatable member disengage the interlocking mechanism when depressed, allowing the rotatable member to be turned to withdraw and extend the bolt. The tabs are in such an arrangement and are so oriented that they are conveniently presented toward the hand of a user located on the side of the door on which the stationary member is mounted, but the hand of a person reaching from the other side of the door cannot readily assume the position necessary to depress the tabs.