Abstract: A bicycle dynamo for a bicycle having a frame and a wheel has a stator, an internal stationary winding fixed on the stator, and an external rotor rotatable on the stator. This rotor has a rotatable cylindrical external casing surrounding the winding and formed with an outwardly open annular groove, a plurality of permanent magnets inside the casing that generate an electrical voltage in the internal stationary stator winding, and an elastic ring frictionally engageable with a rim of the bicycle wheel, set in the annular groove, and projecting from the outer casing. A holder carries the stator.

Abstract: The invention relates to an electric drive for bicycles, comprising two symmetrically arranged external-rotor type counter-rotating motors which are fed via two separate motor actuators/regulators that obtain the same control signal for power regulation purposes. The motors are mounted in an oscillating manner about an axis which is parallel, in particular substantially parallel, to the motor axis but offset with respect to the motor axis in a lateral manner, in particular in a parallel manner.

Abstract: The invention relates to a bicycle dynamo with an external rotor which carries a plurality of permanent magnets on the inside, said permanent magnets generating an electrical voltage in the internal stationary stator winding, wherein the cylindrical outer shell of the external rotor carries an elastic ring for frictional engagement at the rim of the bicycle wheel.

Abstract: The invention relates to an electric drive for bicycles, comprising two symmetrically arranged external-rotor type counter-rotating motors which are fed via two separate motor actuators/regulators that obtain the same control signal for power regulation purposes. The motors are mounted in an oscillating manner about an axis which is parallel, in particular substantially parallel, to the motor axis but offset with respect to the motor axis in a lateral manner, in particular in a parallel manner.

Abstract: An oil supply device has a reservoir adapted to contain oil having a predetermined oil level; a drive shaft extending into the reservoir; a disc affixed to the shaft and being arranged to be submerged at least partially in the oil contained in the reservoir; and a trough affixed to the disc for rotation therewith as a unit. The trough extends arcuately and is radially inwardly open as viewed relative to the disc. Further, the trough is arranged to be submerged at least partially in the oil contained in the reservoir. There is also provided an oil conduit having a stationarily supported terminal portion accommodated in the reservoir and projecting into the trough. The oil conduit is provided with an open end situated in the trough and oriented opposite an operational rotary direction of the disc, whereby oil is driven into the terminal portion through the open end from the trough upon rotation of the drive shaft to supply oil under pressure in the oil conduit.

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: An oil-sealed vacuum pump comprises an oil circuit for supplying a pump chamber and bearings of the vacuum pump with oil. The oil circuit includes first and second branch conduits leading to the bearings and the pump chamber, respectively. The vacuum pump further has an oil pump coupled to the oil circuit for driving oil therethrough, a valve assembly coupled to the oil circuit for shutting off oil supply to the pump chamber during standstill of the vacuum pump, and a pressure reducer coupled to the oil circuit for reducing the oil pressure to environmental pressure. The first branch conduit leading to the bearings is situated upstream of, and the second branch conduit leading to the pump chamber and the valve assembly are situated downstream of the pressure reducer as viewed in the direction of oil flow in the oil circuit.

Abstract: A vacuum pump comprises a suction nipple valve including a cylinder, a piston slidably received therein and a movable valve closing member operatively connected to the piston. The vacuum pump further has a pressure medium conduit having a first end communicating with the cylinder; an inlet opening at a second end of the conduit for pressure medium to flow through the inlet opening to the piston; a control arrangement for closing and opening the inlet opening dependent upon run or standstill of the vacuum pump. In the closed state of the inlet opening an oil quantity is maintained above the inlet opening.