Abstract: An oil pump unit includes an additional outlet port connected to the downstream side of the pump through the pump cover. With this additional port, the oil pump unit is able to have electronic vacuum and pressure sensors upstream and downstream of the pump for remote monitoring of the pump. The invention is particularly suited for oil pump units which have a main discharge outlet port through the one side of the pump body and a main inlet port through an opposing side of the pump cover. The invention is also particularly suited for oil pump units having a solenoid valve mounted at the top side of the pump body which prevents installation of a pressure sensor along the top side.

Abstract: Provided is a gasket for a fuel pump unit configured with a second outlet port for accommodating a pressure sensor to monitor the downstream pressure of pumped fuel. The gasket is adapted for placement between a pump cover incorporating the second outlet port and a pump body containing a gear pump. Providing fluid communication between a first outlet port downstream of the gear pump and the second outlet port is a passageway disposed through the pump cover and pump body. To avoid obstructing the passageway, the gasket includes an aperture. To prevent high pressure fuel from being forced through the gasket and leaked from the pump unit, the gasket includes a leakage collection channel having a first leg, a second leg and an intermediate portion surrounding the aperture. The leakage collection channel is adapted to return leaked fuel to a low pressure reservoir between the pump cover and pump body.

Abstract: The present invention is directed toward a filter head that is adapted to mount a filter between an upstream fluid supply and a downstream fluid pump such as might be used for an oil burner system that includes a combination of the filter head and the safety valve in a single unit that may be interposed at a location along an oil conduit. The filter head comprises a filter head housing having an inlet port and an outlet port and a filter mounting stub that is adapted to mount the filter thereto. The filter mounting stub provides a filter head entrance port and a filter head exit port fluidically between the inlet and the outlet ports for communication with the filter when mounted thereto. A safety valve is mounted in the filter head housing and is arranged fluidically between the inlet and outlet port of the filter head housing. The safety valve has open and closed positions and opens in response to vacuum pressure at the outlet port.

Abstract: A fuel oil supply circuit that includes two bypass mechanisms for burner startup including an electrical valve bypass in parallel circuit with a mechanical valve bypass. The fuel oil supply circuit includes an oil pump that is adapted to pressurize fuel oil and a downstream regulating valve assembly that is adapted to regulate pressurized fuel flow to the nozzles of the burner. A solenoid valve controls flow of pressurized fuel oil through the regulating valve assembly to the nozzles. The solenoid valve has a first state keeping the regulating valve assembly closed, and a second state allowing the regulating valve assembly to open. A diaphragm valve is fluidically connected to the pump in parallel circuit with the regulating piston assembly to provide an alternative bypass mechanism as a backup for the electrical solenoid valve.

Abstract: An oil pump unit includes an additional outlet port connected to the downstream side of the pump through the pump cover. With this additional port, the oil pump unit is able to have electronic vacuum and pressure sensors upstream and downstream of the pump for remote monitoring of the pump. The invention is particularly suited for oil pump units which have a main discharge outlet port through the one side of the pump body and a main inlet port through an opposing side of the pump cover. The invention is also particularly suited for oil pump units having a solenoid valve mounted at the top side of the pump body which prevents installation of a pressure sensor along the top side.

Abstract: A plug for plugging a first port and blocking insertion of a second plug into a second port of a fluid system. The plug includes a threaded plug portion and a blocking stem portion extending from the threaded plug portion. The stem portion projects into the second port and blocks insertion or mounting of a second plug and thereby keeps the second port unplugged. In a disclosed embodiment, the plug is mounted into the return port of an oil pump unit of an oil burner to block bypassed flow from returning to the local reservoir of the oil pump unit. This prevents two plugs from being inadvertently mounted that could otherwise block all bypass flow in the pump unit and cause excess pressure build ups and blown seals.

Abstract: A plug for plugging a first port and blocking insertion of a second plug into a second port of a fluid system. The plug includes a threaded plug portion and a blocking stem portion extending from the threaded plug portion. The stem portion projects into the second port and blocks insertion or mounting of a second plug and thereby keeps the second port unplugged. In a disclosed embodiment, the plug is mounted into the return port of an oil pump unit of an oil burner to block bypassed flow from returning to the local reservoir of the oil pump unit. This prevents two plugs from being inadvertently mounted that could otherwise block all bypass flow in the pump unit and cause excess pressure build ups and blown seals.

Abstract: A fuel oil supply circuit that includes two bypass mechanisms for burner startup including an electrical valve bypass in parallel circuit with a mechanical valve bypass. The fuel oil supply circuit includes an oil pump that is adapted to pressurize fuel oil and a downstream regulating valve assembly that is adapted to regulate pressurized fuel flow to the nozzles of the burner. A solenoid valve controls flow of pressurized fuel oil through the regulating valve assembly to the nozzles. The solenoid valve has a first state keeping the regulating valve assembly closed, and a second state allowing the regulating valve assembly to open. A diaphragm valve is fluidically connected to the pump in parallel circuit with the regulating piston assembly to provide an alternative bypass mechanism as a backup for the electrical solenoid valve.

Abstract: A fuel supply unit adapted to supply a relatively constant flow of fuel oil to an oil burner independently of the pressure of the fuel at a discharge port. The fuel supply unit includes a pump which draws fuel oil from a storage tank and which supplies pressurized fuel to an outlet chamber. The fuel then flows from the outlet chamber to the burner by way of the discharge port. A metering orifice is located between the outlet chamber and the discharge port to control the flow rate of the fuel delivered to the burner, the volumetric flow rate of fuel being related to the pressure differential across the metering orifice. A regulating valve senses the pressure of the fuel at the discharge port and adjusts the pressure of the fuel in the outlet chamber to maintain a relatively constant pressure differential across the metering orifice.

Abstract: A relief valve is built into the nozzle port of a fuel pump for an oil burner and opens to relieve pressure in the fuel supply line and prevent oil from dripping out of the burner nozzle when the pump is shut down. The relief valve comprises a ball which is normally held in a closed position by an arcuate leaf spring wrapped partially around the nozzle port.

Abstract: A gear pump includes a valve member adapted to engage a valve seat and close a control port and urged to an open position by a coil spring. In order to reduce cocking of the valve member relative to the valve seat when the valve member is closed, the end coil of the spring that engages the valve member is formed so as to be in non-parallel relation with the sealing surface of the valve seat when the spring is relaxed. As the spring is compressed during closure of the valve member, the end coil moves into parallelism with the sealing surface in order to enable the valve member to squarely engage the sealing surface.

Abstract: A gear pump in which a gear is secured to a shaft by a press fit and by a key which fits into a slot in the shaft. The key includes radially projecting ears which fit into keyways in the bore of the gear, the keyways having bottoms facing axially toward the bottom of the slot. A hot upset at the free end of the shaft clamps the key axially between the bottom of the slot and the bottom of the keyways. When the shaft/gear/key subassembly is assembled with the body and the end plate of the pump, the gear retention elements described above coact to positively prevent the shaft from being pulled out of the body and from being thrust inwardly into contact with the end plate.

Abstract: A gear pump receives fuel oil from an intake line leading from a storage tank and supplies pressurized fuel to a regulating valve which selectively opens and closes to control the flow of fuel to an oil burner. When the pump first starts but before the regulating valve opens, fuel bypasses the regulating valve and is returned to the tank along with any air that might be in the system, the system thus being automatically purged of air. After the regulating valve opens, excess fuel which is not required by the oil burner is returned directly to the inlet of the pump for recirculation and bypasses both the seal chamber of the pump and the storage tank so as to enable low flow velocity to be maintained in the intake line leading from the tank to the pump and thereby prevent cavitation at the pump when the fuel is of high viscosity. Only a small flow of fuel is directed to the seal chamber to lubricate the shaft of the pump.

Abstract: A two-stage gear pump with two gear sets each having a spur gear telescoped onto a slotted drive shaft with a press fit and also positively keyed to the shaft. An annular groove is formed around the shaft adjacent the closed end of the slot in the shaft and enables the slot to be relatively short in axial length so as to reduce manufacturing problems and to enhance the press fit between the shaft and the first stage spur gear.

Abstract: A gear pump in which a drive shaft is telescoped into a bore in a spur gear and is held against rotation relative to the gear by means of a key fitting into keyways formed in the shaft and in the bore of the gear. To retain the shaft against axial movement relative to the gear, a spring steel ring is formed with a radially extending slot having a transverse width just slightly greater than the transverse width of the key. The ring is collapsed hoopwise into a groove in the shaft and is positioned such that the slot in the ring is alined axially with the keyway in the shaft. When the shaft is telescoped to a predetermined depth in the bore in the gear, the ring expands hoopwise and snaps into a groove formed in the wall of the bore. The coaction of the ring with the two grooves locks the shaft against axial movement relative to the gear.

Abstract: The regulating valve of a gear pump for an oil burner is urged to a closed position by a spring-loaded plunger. An adjusting screw is associated with the plunger and, when turned, causes the plunger to shift longitudinally so as to adjust the spring force applied to the valve. The screw is threadably received within a nut which is formed integrally with a sleeve. A pump inlet fitting extends through the sleeve to fasten the sleeve to the body of the pump. The inlet fitting and the sleeve coact to prevent rotation of the nut when the adjusting screw is turned.

Abstract: A two-stage gear pump with two gear sets each having a pinion telescoped onto a slotted drive shaft with a press fit and also positively keyed to the shaft. One key in the slot of the shaft includes radial ears establishing a positive coupling between the shaft and one of the pinions and also includes cantilevered spring fingers which enhance the press fit between the shaft and the other pinion.

Abstract: The pinion gear of a gear pump is press fit onto the end portion of the drive shaft of the pump and is positively captivated on the shaft by a key and by a hot upsetting process, the latter resulting in the formation of axially protruding burrs on the end face of the shaft. When the drive shaft is rammed forwardly with significant force, the burrs tend to embed in an end plate disposed in opposing relation with the shaft. To prevent the burrs from embedding in the end plate and locking the shaft against rotation, the end plate is formed with a recess which receives the burrs with substantial axial clearance when the shaft is rammed forwardly against the end plate.