Rotary pump with a lubricant feed connecting a rotor bearing and a radial sealing gap

Patent metadata

Field	Value
Publication number	US-11280336-B2
Application number	US-201916369211-A
Country	US
Kind code	B2
Filing date	Mar 29, 2019
Priority date	Mar 29, 2018
Publication date	Mar 22, 2022
Grant date	Mar 22, 2022

Abstract

A rotary pump, the rotational direction of which can preferably be switched, featuring: a housing including a pump space featuring an inlet into a low-pressure region of the pump space for a fluid to be pumped and an outlet from a high-pressure region of the pump space for the fluid to be pumped; at least one rotor which forms delivery cells in the pump space; a bearing; and a sealing stay which axially faces the at least one rotor and separates the low-pressure region from the high-pressure region in the rotational direction of the at least one rotor; and featuring at least one lubricant feed, in the sealing stay, which feeds a fluid, as a lubricant, from at least one of the delivery cells to the bearing.

First claim

The invention claimed is:

1. A rotary pump, the rotational direction of which can be switched, comprising:
a) a housing comprising a pump space featuring an inlet into a low-pressure region of the pump space for a fluid to be pumped and an outlet from a high-pressure region of the pump space for the fluid to be pumped;
b) at least one rotor which forms delivery cells in the pump space;
c) at least one bearing;
d) at least one sealing stay which axially faces the at least one rotor and separates the low-pressure region from the high-pressure region in the rotational direction of the at least one rotor; and
e) at least one lubricant feed, in the at least one sealing stay, which feeds a fluid, as a lubricant, from at least one of the delivery cells to the bearing, wherein the at least one lubricant feed connects at least two adjacent delivery cells to each other in at least one position of the at least one rotor.

2. The rotary pump according to claim 1 , wherein the housing comprises an inner circumferential wall which radially delineates the pump space and, together with the at least one rotor, forms a radial sealing gap between the inner circumferential wall and a radial outer end of the at least one rotor, wherein the radial sealing gap varies in size in the rotational direction of the at least one rotor.

3. The rotary pump according to claim 2 , wherein the radial sealing gap has a radial width which is smaller, in a circumferential region of the inner circumferential wall which lies opposite the at least one lubricant feed, than an average radial width of the radial sealing gap.

4. The rotary pump according to claim 2 , wherein the radial sealing gap in a circumferential region between the low-pressure region and the at least one lubricant feed, and/or the radial sealing gap in a circumferential region between the high-pressure region and the at least one lubricant feed, has a radial width which is larger than a radial width of the radial sealing gap in the circumferential region opposite the at least one lubricant feed.

5. The rotary pump according to claim 1 , wherein the at least one lubricant feed is a recess which extends in the radial direction from the at least one bearing up to and into the at least one of the delivery cells which passes over the recess.

6. The rotary pump according to claim 1 , wherein the at least one lubricant feed comprises at least one elongation which extends substantially in and/or counter to the rotational direction of the rotary pump, at or near an end which faces away from the at least one bearing.

7. The rotary pump according to claim 1 , wherein there is no position of the at least one rotor at which the at least one lubricant feed is short-circuited with the inlet into the pump space or the outlet from the pump space.

8. The rotary pump according to claim 1 , wherein: the rotary pump comprises two rotors including the at least one rotor and a second rotor in the form of toothed wheels; the two toothed wheels mesh with each other in a driving stay; each of the two rotors is assigned a bearing, a sealing stay, and a lubricant feed; and the respective lubricant feeds of the two rotors are connected to each other via the driving stay.

9. The rotary pump according to claim 1 , further comprising an electric motor which drives the at least one rotor.

10. The rotary pump according to claim 1 , wherein the rotary pump is an external-axle pump.

11. The rotary pump according to claim 1 , wherein the at least one lubricant feed is a groove which extends in the radial direction from the bearing up to and into at least one delivery cell which passes over the groove.

12. The rotary pump according to claim 1 , wherein the rotary pump is an externally toothed wheel pump.

13. The rotary pump according to claim 1 , wherein the at least one lubricant feed is embodied in the shape of a T.

14. A rotary pump, a rotational direction of which can be switched, comprising:
a) a housing comprising a pump space featuring an inlet into a low-pressure region of the pump space for a fluid to be pumped, an outlet from a high-pressure region of the pump space for the fluid to be pumped, and an inner circumferential wall which radially delineates the pump space;
b) at least one rotor which forms delivery cells in the pump space and, together with the inner circumferential wall, forms a radial sealing gap to seal off adjacent delivery cells; and
c) at least one sealing stay which axially faces the at least one rotor and separates the low-pressure region from the high-pressure region in the rotational direction of the at least one rotor,
wherein
d) the radial sealing gap varies in size in the rotational direction of the rotor,
wherein the inner circumferential wall comprises at least one circumferential region which radially extends into the pump space,
wherein the inner circumferential wall comprises a first circumferential region between the low-pressure region and the high-pressure region, a second circumferential region between the low-pressure region and the high-pressure region, and a third circumferential region between the low-pressure region and the high-pressure region, wherein the radial sealing gap in the first and third circumferential region is larger than the sealing gap in the second circumferential region,
wherein the second circumferential region protrudes radially inwards from the inner circumferential wall, and
wherein the second circumferential region is positioned in the sealing stay centrally viewed in the rotational direction of the at least one rotor between the first and third circumferential region.

15. A rotary pump, the rotational direction of which can be switched, comprising:
a) a housing comprising a pump space featuring an inlet into a low-pressure region of the pump space for a fluid to be pumped and an outlet from a high-pressure region of the pump space for the fluid to be pumped;
b) at least one rotor which forms delivery cells in the pump space;
c) at least one bearing; and
d) at least one sealing stay which axially faces the at least one rotor and separates the low-pressure region from the high-pressure region in the rotational direction of the at least one rotor; and
e) at least one lubricant feed, in the at least one sealing stay, which feeds a fluid, as a lubricant, from at least one of the delivery cells to the at least one bearing,
f) wherein the housing comprises an inner circumferential wall which radially delineates the pump space and, together with the at least one rotor, forms a radial sealing gap between the inner circumferential wall and a radial outer end of the at least one rotor, wherein a width of the radial sealing gap varies in size along the inner circumferential wall in the rotational direction of the at least one rotor, and
g) wherein the width of the radial sealing gap in a circumferential region between the low-pressure region and the at least one lubricant feed and the width of the radial sealing gap in a circumferential region between the high-pressure region and the at least one lubricant feed are respectively larger than the width of the radial sealing gap in the circumferential region opposite the at least one lubricant feed,
h) wherein the circumferential region opposite the at least one lubricant feed of the circumferential wall extends radially towards the at least one rotor to define the reduced width of the radial sealing gap positioned thereat.

Assignees

• Shw Automotive Gmbh

Inventors

• Ehringer Michael
• Jäggle Gerd
• Peters Sven
• Braasch Holger
• Baur Winfried

Classifications

• F04C2/30

  having the characteristics covered by two or more groups F04C2/02, F04C2/08, F04C2/22, F04C2/24 or having the characteristics covered by one of these groups together with some other type of movement between co-operating members · CPC title

• F01M1/02

  using lubricating pumps (pumps in general F04; lubricating pumps per se F16N) · CPC title

• F04C15/0088 Primary

  Lubrication (of machines or engines in general F01M) · CPC title

• F04C2/084

  Toothed wheels · CPC title

• F04C2/10 Primary

  of internal-axis type with the outer member having more teeth or tooth-equivalents, e.g. rollers, than the inner member · CPC title