Abstract: A valve seat retainer is formed having a flange that extends over the valve seat and that applies both a radial and a longitudinal force to the valve seat. The flange extends an order of magnitude further than typical prior art valve seat retaining flanges. The flange is created by a rolling method with a roller having a unique surface profile. The roller surface has a pair of spaced ridges with a groove in between, and a curved convex surface adjacent to one of the ridges. When a downward force is applied to the roller, the curved surface on the roller causes the roller to move radially inward while at the same time material from the upper surface of the engine block is disposed in the groove and is moved to create the flange.

Abstract: A valve seat retainer is formed having a flange that extends over the valve seat and that applies both a radial and a longitudinal force to the valve seat. The flange extends an order of magnitude further than typical prior art valve seat retaining flanges. The flange is created by a rolling method with a roller having a unique surface profile. The roller surface has a pair of spaced ridges with a groove in between, and a curved convex surface adjacent to one of the ridges. When a downward force is applied to the roller, the curved surface on the roller causes the roller to move radially inward while at the same time material from the upper surface of the engine block is disposed in the groove and is moved to create the flange.

Abstract: A piston--piston ring assembly for an internal combustion engine reduces hydrocarbon emissions without significantly increasing the cost of the engine. The assembly includes an upper piston ring groove and a piston ring which acts as check valve to prevent combustion gases trapped below the upper piston ring from re-entering the combustion chamber when the exhaust valve is opened. The invention also includes a venting means for providing fluid flow communication between the crankcase side of the upper piston ring and the crankcase, around one or more lower piston rings, so that any trapped combustion gases are vented only in the downward direction toward the crankcase. The venting means includes a vent passageway slot in the lower piston groove, as well as an aperture adjacent to the lower piston ring groove.

Abstract: The internal combustion engine includes a cast cylinder head having as-cast alignment ribs that align a squared-off fulcrum in the rocker assembly. The rocker arm also has two substantially flat surfaces that engage the planar sides of the fulcrum to minimize lateral movement of the rocker arm. The fulcrum is received between the cast alignment ribs. The ribs are biased from a major axis to insure proper fulcrum alignment during assembly without the use of a jig.

Abstract: The cylinder head assembly includes a cast member, and a substantially planar member that is affixed to an upper end of the cast member. The substantially planar member includes apertures to anchor the intake and exhaust rocker studs, apertures that receive the intake and exhaust valve, and apertures that receive the push rod guides. The substantially planar member also has spring locators for the intake and exhaust valve return springs. The cast member is affixed to the engine cylinder, and includes cast intake and exhaust manifolds, bosses for receiving the intake and exhaust valves, a cast pocket for receiving the intake and exhaust push rods, and air cooling fins. A head cover is disposed on an opposite side of the planar member. The invention eliminates the need for two cast components.

Abstract: A pour spout for conducting fluid from a container to a receptacle. The pour spout includes a conduit member having a first end interconnectable with the container and a second end having a discharge opening and a vent opening, and a closure member positioned adjacent to the discharge opening. The closure member is movable relative to the conduit member between a first position where the discharge and vent openings are closed, a second position where the vent opening is open, and a third position where the discharge opening is open. A closure locking device prevents bypassing the second position during movement of the closure member from the first position to the third position. A vent locking device prevents movement of the closure member from the first position to the second position when the container is tipped beyond a predetermined angle. Another device retains sub-ambient pressure within the container when closure member is in the second position.

Abstract: The improved battery-powered lawnmower includes a safety key that is automatically removed when the removable battery is removed, while at the same time blocking the battery recharger receptacle. The lawnmower also includes a control circuit that shuts off the lawnmower upon the occurrence of one or more of several predetermined conditions, including low battery voltage, the encountering of heavy grass for a period of 3 seconds or more, and high motor current that may occur when the cutting blade is jammed. The cutting blade is designed to move through any debris accumulated between the blade ends and the housing sidewall without sacrificing the lift for needed cutting and mulching. The invention also includes a unique height adjustment assembly for adjusting the height of the chassis, a handle attachment that allows the handle to be positively tightened to the lawnmower chassis, and a telescoping groove for the battery's quick connect/disconnect terminals.

Abstract: The improved battery-powered lawnmower includes a safety key that is automatically removed when the removable battery is removed, while at the same time blocking the battery recharger receptacle. The lawnmower also includes a control circuit that shuts off the lawnmower upon the occurrence of one or more of several predetermined conditions, including low battery voltage, the encountering of heavy grass for a period of 3 seconds or more, and high motor current that may occur when the cutting blade is jammed. The cutting blade is designed to move through any debris accumulated between the blade ends and the housing sidewall without sacrificing the lift for needed cutting and mulching. The invention also includes a unique height adjustment assembly for adjusting the height of the chassis, a handle attachment that allows the handle to be positively tightened to the lawnmower chassis, and a telescoping groove for the battery's quick connect/disconnect terminals.

Abstract: The engine governor outputs a pulse width modulated actuator control signal at two or more frequencies to improve actuator performance. In one embodiment, the control signal has a frequency of about 60 to 70 hertz when the throttle is nearly closed, and switches to a frequency of between 5 to 30 hertz once the throttle is between 50 to 75 percent open. In a second embodiment, the frequency of the actuator control signal decreases in a linear manner from 60 to 70 hertz to between 5 to 30 hertz as the throttle is opened from a closed throttle position to wide open throttle. A decrease in frequency with increased throttle opening provides additional control signal off time, thereby allowing the magnetic field in the actuator to sufficiently dissipate for proper dithering action.

Abstract: The low cost speed governor is used to provide stable device speed over a wide range of selected reference speeds and loads. The speed governor includes a means for changing the pulse width of a pulsed reference signal as a function of the selected reference speed and the load applied to the device. Operational stability is achieved at low reference speeds by automatically increasing the speed droop as the selected reference speed is lowered and as the applied load is increased. Overall governor cost is reduced by an arrangement that uses the same potentiometer to both vary the selected reference speed and to automatically change the speed droop.

Abstract: A lock for the ignition circuit for an automobile including a Hall effect control sensor which is activated by a control magnet on the cylinder member of the lock so that when the cylinder is rotated by the key to its start position, the control sensor is activated. The activation of the control sensor provides one of several starting criteria to an ignition for starting an automobile. An anti-tampering sensor spaced from and adjacent to the control sensor has a trip level which is lower than the trip level of the control sensor so that magnetic forces induced from the exterior of the lock cannot trip the control sensor. A blocking plate is disposed between the control sensor and the anti-tampering sensor to prevent the anti-tampering sensor from being tripped by the control magnet when the cylinder member is rotated to its start position and to enable the anti-tampering sensor to be tripped first to produce a deactivation signal in response to a magnetic force induced from the exterior of the lock.

Abstract: The catalytic muffler for small internal combustion engines has a venturi with a flattened profile formed from two stamped pieces, namely the muffler housing and the separator plate. This design eliminates the need for a separate piece of tubing or machined part, as is required in prior art round venturi devices. The catalytic muffler also includes a noise attenuator disposed upstream of the catalyst, thereby eliminating the back pressure which is otherwise applied to the venturi when the noise attenuator is disposed downstream of the catalyst. In addition, back pressure on the venturi is reduced by sizing the port in the separator plate and the exhaust port so that their respective cross sectional areas are substantially equal to the cross sectional area of the catalyst.

Abstract: An engine housing for a vertical crankshaft engine may be directly mounted to a standard generator, pump, or other device without modifying the device housing. The engine housing has a plurality of raised mounting bosses that are used to attach the device housing to the engine housing. If the engine housing has an oil slinger well, the raised mounting bosses extend from the engine housing surface a sufficient distance to provide clearance for the oil slinger well. The engine housing also has a pilot that either receives an adapter ring or a portion of a device pilot to maintain the concentricity between the engine crankshaft and the device shaft, as well as the proper alignment between the engine housing and the device housing.

Abstract: The low cost speed governor for internal combustion engines may be completely powered by the ignition coil. The governor receives a periodic signal from the primary ignition winding that is indicative of the actual speed of the engine. A pulsed speed signal is generated that is functionally related to the periodic signal. The pulsed speed signal has a pulse width that is functionally related to the actual engine speed. A pulsed reference signal is generated by a timer circuit, and has a pulse width that is functionally related to a predetermined reference speed. The pulsed speed signal is then compared with the pulse reference signal by a comparator circuit, and a pulsed error signal is generated that has a pulse width which is functionally related to the difference between the speed signal pulse width and the reference signal pulse width. The speed of the device is then changed by a transistor bridge network as a function of the error signal.

Abstract: A valve seat retainer is formed having a flange that extends over the valve seat and that applies both a radial and a longitudinal force to the valve seat. The flange extends an order of magnitude further than typical prior art valve seat retaining flanges. The flange is created by a rolling method with a roller having a unique surface profile. The roller surface has a pair of spaced ridges with a groove in between, and a curved convex surface adjacent to one of the ridges. When a downward force is applied to the roller, the curved surface on the roller causes the roller to move radially inward while at the same time material from the upper surface of the engine block is disposed in the groove and is moved to create the flange.

Abstract: The air vane governor has improved speed droop characteristics under no load and light load conditions to prevent engine stumbling. The air vane governor includes a primary spring and a secondary spring; both springs oppose the movement of the air vane at no load and light load conditions. At increased load, the secondary spring drops out. The tension on both springs is adjustable. The added spring force of the secondary spring makes the governor less sensitive at no load and light load, resulting in more even operation, particularly during engine warmup.

Abstract: A dynamic gas seal for an internal combustion engine reduces exhaust emissions by minimizing the amount of hydrocarbon-laden air from the engine breather that enters the combustion chamber through the open intake valve. The dynamic gas seal includes several channels which allow filtered air at atmospheric pressure to enter the combustion chamber in place of oil-laden air from the breather. The dynamic gas seal includes a channel between the air filter and the intake valve system, and channels between the breather exit and the carburetor intake.