Abstract: A sock or bag-type liquid filtering device for use in filtering liquids such as water to remove debris includes a sock or bag of disposable filter material having a rim releasably secured to a two part filter holder. In one embodiment, the holder is designed to engage in an opening of a fish tank filter plate with the filter bag extending through the opening. A first holder part or flanged ring engages inside the rim of the bag and a second holder part or retainer ring engages over the flanged ring and bag rim. In one example the retainer ring is designed for snap engagement over the flanged ring with gripping formations on at least one of the parts, and the bag rim is gripped between the rings.

Abstract: A sock or bag-type liquid filtering device for use in filtering liquids such as water to remove debris includes a sock or bag of disposable filter material having a rim releasably secured to a two part filter holder. In one embodiment, the holder is designed to engage in an opening of a fish tank filter plate with the filter bag extending through the opening. A first holder part or flanged ring engages inside the rim of the bag and a second holder part or retainer ring engages over the flanged ring and bag rim. In one example the retainer ring is designed for snap engagement over the flanged ring with gripping formations on at least one of the parts, and the bag rim is gripped between the rings.

Abstract: A fuel control device or fuel valve assembly includes a valve for metering flow of gaseous fuel to an engine, a drive device associated with the valve to adjust the effective flow area of the valve, a flow meter with at least one fixed area orifice located upstream of the valve, and one or more sensors to measure predetermined parameters of the fuel flowing through the flow meter. A controller receives input from the flow sensor or sensors and a fuel demand signal from the engine control, calculates current flow rate based on the sensor inputs, and controls the drive device to adjust the valve flow area up or down depending on the difference between the calculated flow rate and current fuel demand signal.

Abstract: A gas substitution ratio control system varies natural gas flow to a bi-fuel engine based on detected diesel flow to maintain a desired gas substitution ratio (GSR), without any requirement to sense engine load. In other words, GSR is controlled without monitoring engine load level. In one system, an engine is first calibrated to map actual gas and diesel flows to provide the correct GSR for all engine loads. The calibration data is then stored and diesel flow rate is monitored. The current detected diesel flow rate is used to determine the required gas flow rate for correct GSR. Gas flow to the engine is then adjusted to correspond to the required gas flow rate. Other embodiments meter gas to maintain the diesel flow rate at the same minimum level for all loads, or meter gas and diesel fuel flows to match a map of the limiting fuel energy based GSR (gas fuel energy rate/total fuel energy rate) at all loads for each engine model.

Abstract: A gaseous fuel and air mixing venturi device is adapted for installation in a gaseous fuel carburetor and has a venturi body defining annular inner and outer venturi passageways which each have a throat of reduced cross-sectional area and have inlet ends in communication with an air inlet of the carburetor. A fuel inlet is configured for connection to a fuel port of the carburetor, and communicates with a plurality of fuel supply ports in the body communicating radially with the inner and outer venturi passages to mix with the air flowing in the passageways.

Abstract: A door latch assembly for engagement in a mounted position at or adjacent to a side edge of a door which abuts a door frame stop upon a full closure of the door into a surrounding door frame. The device features an angled or biased latch member which employs an end to engage the door stop molding of a door jamb and thereby secure the door in a slightly open position and prevent a full opening of the door. The latch member is engaged to a side edge of the door using frictional engagement or mechanical engagement. The latch member is releasable from either side of the door without placing a user's fingers in between the door and jamb.

Abstract: Systems and methods for continuous automatic adjustment of a control set point of an air-fuel ratio controller of a rich burn engine so as to maintain emissions within a desired range. In an embodiment, a NOx sensor is placed in the exhaust outlet from an exhaust catalyst and the NOx exhaust sensor output is continuously monitored while adjusting the control set point between rich and lean in order to minimize the output from the NOx sensor. Corrections may be continuously made to the set point during operation of the engine to compensate for changes in environmental conditions, engine loads, and other factors.

Abstract: A fuel control device or fuel valve assembly includes a valve for metering flow of gaseous fuel to an engine, a drive device associated with the valve to adjust the effective flow area of the valve, a flow meter with at least one fixed area orifice located upstream of the valve, and one or more sensors to measure predetermined parameters of the fuel flowing through the flow meter. A controller receives input from the flow sensor or sensors and a fuel demand signal from the engine control, calculates current flow rate based on the sensor inputs, and controls the drive device to adjust the valve flow area up or down depending on the difference between the calculated flow rate and current fuel demand signal.

Abstract: A gaseous fuel and air mixing venturi device is adapted for installation in a gaseous fuel carburetor and has a venturi body defining annular inner and outer venturi passageways which each have a throat of reduced cross-sectional area and have inlet ends in communication with an air inlet of the carburetor. A fuel inlet is configured for connection to a fuel port of the carburetor, and communicates with a plurality of fuel supply ports in the body communicating radially with the inner and outer venturi passages to mix with the air flowing in the passageways.

Abstract: A gas substitution ratio control system varies natural gas flow to a bi-fuel engine based on detected diesel flow to maintain a desired gas substitution ratio (GSR), without any requirement to sense engine load. In other words, GSR is controlled without monitoring engine load level. In one system, an engine is first calibrated to map actual gas and diesel flows to provide the correct GSR for all engine loads. The calibration data is then stored and diesel flow rate is monitored. The current detected diesel flow rate is used to determine the required gas flow rate for correct GSR. Gas flow to the engine is then adjusted to correspond to the required gas flow rate. Other embodiments meter gas to maintain the diesel flow rate at the same minimum level for all loads, or meter gas and diesel fuel flows to match a map of the limiting fuel energy based GSR (gas fuel energy rate/total fuel energy rate) at all loads for each engine model.

Abstract: A door latch assembly for engagement in a mounted position at or adjacent to a side edge of a door which abuts a door frame stop upon a full closure of the door into a surrounding door frame. The device features an angled or biased latch member which employs an end to engage the door stop molding of a door jamb and thereby secure the door in a slightly open position and prevent a full opening of the door. The latch member is engaged to a side edge of the door using frictional engagement or mechanical engagement. The latch member is releasable from either side of the door without placing a user's fingers in between the door and jamb.

Abstract: A door latch assembly for engagement in a mounted position to a side edge of a door. The device features an angled or biased latch member which employs a hooked end to engage the door stop molding of a doorjamb to secure the door in a slightly open position. The latch member is engaged to a side edge of the door using frictional engagement or mechanical engagement. The latch member is releasable from either side of the door without placing a user's fingers in between the door and jamb.

Abstract: A gaseous carburetor or fuel control system includes a fuel metering assembly, a venturi mixer assembly, a throttle assembly, and an electronic control unit. The control unit controls the fuel metering assembly in a closed loop manner based on detected gas and air pressure to an air/fuel mixing venturi. An electronic governor which controls the throttle valve may also be controlled by the same control unit which controls the fuel metering assembly, using a separate control loop.

Abstract: A gaseous carburetor or fuel control system includes a fuel metering assembly, a venturi mixer assembly, a throttle assembly, and an electronic control unit. The control unit controls the fuel metering assembly in a closed loop manner based on detected gas and air pressure to an air/fuel mixing venturi. An electronic governor which controls the throttle valve may also be controlled by the same control unit which controls the fuel metering assembly, using a separate control loop.

Abstract: A door latch assembly for engagement in a mounted position to a side edge of a door. The device features an angled or biased latch member which employs a hooked end to engage the door stop molding of a doorjamb to secure the door in a slightly open position. The latch member is engaged to a side edge of the door using frictional engagement or mechanical engagement. The latch member is releasable from either side of the door without placing a user's fingers in between the door and jamb.

Abstract: A gaseous fuel and air mixing venturi device adapted for retrofitting in a carburetor has a venturi body with a passage for air flow through the body, the passage having a throat of reduced cross-sectional area. The body has an axial fuel inlet port at a first end and fuel supply ports connected to the fuel inlet port and spaced around the throat for supplying fuel to the air flow passage for mixing with air flowing through the passage. The first end of the venturi body has mating seating formations for seating against corresponding seating surfaces of a gaseous fuel carburetor after removal of a spring mass air/fuel mixing section, and a fastener mechanism for releasably securing the venturi body in the carburetor, with the fuel supply port of the carburetor connected to the fuel inlet port of the venturi body.

Abstract: An emission control device for use with stationary or mobile gas-fueled internal combustion engines is described, which is placed in the fuel supply line and operates with full fuel authority. An oxygen sensor measures exhaust oxygen content. The valve internally houses a programmable microprocessor, a pressure transducer and a fuel flow conduit throttled by a balanced poppet valve. Signals to the microprocessor from the oxygen sensor, the pressure transducer indicating outflow gas pressure cause the microprocessor to motivate an actuator to move the valve within the gas stream and thus regulate the outlet pressure and also the gas flow rate to maintain a desired air/fuel ratio to the engine and keep exhaust emissions at an optimum level consistent with the engine operating load requirements and characteristics. Finite incremental control of valve position, preferably assisted by an internal position transducer, permits close control of the exhaust emissions.

Abstract: An emission control device for use with stationary or mobile gas-fueled internal combustion engines is described, which is placed in the fuel supply line and operates with full fuel authority. An oxygen sensor measures exhaust oxygen content. The valve internally houses a programmable microprocessor, a pressure transducer and a fuel flow conduit throttled by a balanced poppet valve. Signals to the microprocessor from the oxygen sensor, the pressure transducer indicating outflow gas pressure cause the microprocessor to motivate an actuator to move the valve within the gas stream and thus regulate the outlet pressure and also the gas flow rate to maintain a desired air/fuel ratio to the engine and keep exhaust emissions at an optimum level consistent with the engine operating load requirements and characteristics. Finite incremental control of valve position, preferably assisted by an internal position transducer, permits close control of the exhaust emissions.