Abstract: An oil-sealed rotary vacuum pump includes a pump system and an electric drive motor connected by a drive shaft and located within a housing. The housing is divided by a partition into two separate compartments with the pump system in one compartment and the drive motor in the other compartment. The drive shaft extends through a passage in the partition between the two compartments and the passage is arranged so that any leakage flow is directed from the motor compartment into the pump system compartment.

Abstract: A vacuum pump includes an evacuation chamber, a gear chamber, a partition separating the evacuation chamber from the gear chamber, a rotary pump shaft extending through the partition and having one end connected to a vane arranged for rotation in the evacuation chamber and having another, opposite end extending into the gear chamber, a shaft bearing surrounding the pump shaft and received in the partition, a labyrinth seal surrounding the pump shaft and received in the partition for sealing the evacuation chamber from the gear chamber, an oil sump defined in the gear chamber for accommodating oil therein, an evacuation device for generating a vacuum in the gear chamber and an oil loss preventing arrangement for avoiding an oil deficiency in the gear chamber due to the vacuum generated therein.

Abstract: The vane slot 20 and lubricating oil passageway 21 in the cylinder member 3 of a rotary vane compressor are configured such that the radial length of the slot wall 20a on the low pressure side of the vane 5 is less than that of the opposite wall 20b on the high pressure side. Such a shortened low pressure side slot wall reduces wear by providing improved lubrication at the critical inward edge of the slot (F1), and facilitates the flushing away of abrasive particles formed during the initial seating of the vane. For a horizontal installation the lubricating oil level is maintained below the radially outermost edge of the wall 20a to prevent the oil from being drawn into the low pressure chamber 17 when the compressor is stopped.

Abstract: Oil-sealed vane pump has a stator and a rotor assembly housed in an oil-filled tank, said stator comprising an oil injection orifice, a suction port connected to a tank inlet pipe and a discharge port opening into said tank, said discharge port being provided with a check valve, said check valve being mounted in a spot facing in the stator and said tank further comprising a discharge outlet. The stator is provided with at least one slot opening into the spot facing.

Abstract: The invention pertains to a two-stage vacuum pump for servicing refrigeration systems wherein a pair of electrically driven rotors support movable vanes engaging the cylindrical circumference of pumping chambers in which the rotors are mounted. The improvements pertain to the sealing of the rotor shaft, the introduction of metered oil into the pump, and the keying of a rotor to its driveshaft wherein improved assembly and operational characteristics are achieved.

Abstract: A screw compressor with liquid injection wherein the units previously disposed separately from one another, such as the air filter, liquid separator, and so on, are integrated into a single housing. Various compartments are formed in the housing by means of partitions, such that the compartments provide for good separation of entrained liquid from the compressed air being achieved because of large flow cross-section, maximum utilization of the available flowpath and multiple deflection of the current of compressed air. The compact construction results in a substantially smaller overall compressor size than that of comparable known compressor plants, in a reduction of manufacturing cost and simplification of the assembly of a compressor plant.

Abstract: An oil pool in a rotary vane, oil sealed mechanical vacuum pump casing is cooled by air drawn by a relatively low pressure and low speed laminar flow fan mounted on a motor shaft for the pump and positioned in a shroud between end plates for the motor and casing. The air pumped by the fan flows axially relative to the shaft through a horizotally extending slot at the bottom of the shroud and vertically extending slots on the sides of the shroud. The pumped air flows against vertically and horizontally extending fins respectively on the pump casing bottom and sides. The vertically extending fins at the bottom of the casing have bases slightly above the horizontal slot at the bottom of the housing so air flowing through that slot flows against the bases of the fins at a shallow angle. A vertical surface of the housing remote from the fan and the shroud has vertically extending fins that are aligned with the vertically extending fins on the bottom of the casing.

Abstract: A rotary vane vacuum pump includes a drive unit, such as an electric motor, and a pump unit, preferably constructed as a cartridge pump unit. The drive unit may take any suitable form, but the cartridge unit includes one or more pumping stages plus a pumping stage of small dimension to lower pressure and increase outgassing of the lubricant. The rotors of the rotary vane pump unit are shaftless, that is they together form an axis of rotation without a separate axial shaft and are thus simplified in construction. All of the requirements of oiling, outgassing and gas ballast are fulfilled in the additional stage.