Bearing module for a vacuum pump
A bearing module for supporting a rapidly rotatable shaft of a vacuum pump includes a rolling bearing for supporting rotatably the shaft, a reservoir for a lubricant having an element forming a sliding contact with a delivery structure supported on the shaft for delivery of the lubricant in the rolling bearing under action of centrifugal forces generated during rotation of the shaft, and a radial delivery element provided on a side of the rolling bearing opposite a side of the bearing at which the delivery structure is located, for returning the lubricant to the reservoir.
1. A vacuum pump, comprising a housing; a shaft rotatably supported in the housing; and a bearing module located in the housing for rotatably supporting the shaft at one end thereof and including a rolling bearing for rotatably supporting the shaft, a reservoir for a lubricant having an element forming a sliding contact with a delivery structure supported on the shaft for delivery of the lubricant in the rolling bearing under action of centrifugal forces generated during rotation of the shaft, and radial capillary delivery means provided on an end side of the rolling bearing opposite an end side of the rolling bearing at which the delivery structure is located, and formed as a slot for returning the lubricant to the reservoir,
wherein the housing has a cylindrical receptacle for receiving the bearing module, and
wherein the vacuum pump further comprises means for securing the bearing module in the housing receptacle.
2. A vacuum pump according to claim 1 , further comprising a permanent magnetic bearing for supporting the shaft at an end thereof opposite the bearing module.
3. A vacuum pump according to claim 1 , wherein the bearing module includes axial delivery means forming part of a lubricant delivery loop and located between the radial capillary delivery means and the reservoir.
4. A vacuum pump according to claim 1 , wherein the bearing module has first and second parts, and the radial capillary delivery means forming a slot is provided between the first and second parts.
5. A vacuum pump according to claim 1 , wherein the rolling bearing has an outer ring connected with the slot, whereby the lubricant can be delivered from interior of the bearing outwardly.
6. A vacuum pump according to claim 1 , wherein at least one of the first and second parts of the bearing module is adapted for receiving the reservoir.
7. A vacuum pump according to claim 1 , wherein the first and second parts of the bearing module are provided with a coating at least on portions of their surfaces which are in contact with the lubricant, to prevent a chemical change of their material because of reaction with the lubricant.
8. A vacuum pump according to claim 1 , wherein the housing has an upper part in which a pumping system is located, and a lower part in which a pump drive is located, the lower part having at an end thereof remote from the upper part, a cylindrical cavity that form the cylindrical receptacle for receiving the bearing module.
9. A vacuum pump according to claim 1 , wherein the sliding contact-forming element is formed as a radial capillary element.