Vacuum pump
AssigneeEdwards Limited
InventorFrancis Phillip Chatfield
Life of this patent
Estimating the term…
Abstract
A vacuum pump is provided comprising a pumping mechanism, a drive shaft for driving the pumping mechanism and a gear box connected to the drive shaft for rotating the drive shaft. Pressure control means are provided to define a path to allow fluid to flow from the pumping mechanism to the gear box in order to reduce the pressure difference therebetween. A reservoir is located within this path for collecting oil passing along the drive shaft from the gear box towards the pumping mechanism. In use, this enables pressurized fluid flowing from the pumping mechanism towards the gear box to urge oil which has collected in the reservoir, towards the gear box.
Claims18
A vacuum pump comprising:
- a pumping mechanism;
- a drive shaft for driving the pumping mechanism;
- a gear box connected to the drive shaft for rotating the drive shaft;
- and
- pressure control means defining a path to allow fluid to flow from a swept volume of the pumping mechanism into the gear box and vice versa to reduce the pressure difference therebetween, wherein a part of the path is defined by a first conduit extending between the pumping mechanism and the gear box and being separate from and other than a fluid passage along the drive shaft, and, located in said path, a reservoir for collecting oil passing via the fluid passage along the drive shaft from the gear box towards the pumping mechanism so that, in use, pressurised fluid flowing from the pumping mechanism towards the gear box urges oil collected in the reservoir towards the gear box via a second conduit separate from and other than the fluid passage along the drive shaft.
Dependencies are inferred from the claim text.