Vane cell machine with centric bore in ring insert in side wall

Abstract

A vane cell machine (1) is described comprising a stator (2) and a rotor (3), said rotor (3) having radially displaceable vanes (4) bearing on an inside (5) of the stator (2) and bordering, together with the rotor (3), the stator (2), and a side wall (7) at each axial end of the rotor (3), work chambers (6) the volume of which changes during a rotation of said rotor, at least one side wall (7) bearing an insert in form of a ring (9). Such a machine should be of simple construction. To this end, said ring (9) comprises a centric bore (10).

Claims

1. A vane cell pump comprising: a stator; and a rotor; wherein said rotor having radially displaceable vanes bearing on an inside of the stator and bordering, together with the rotor, the stator, and a side wall at each axial end of the rotor, at least one side wall bearing an insert in form of a ring; and wherein said ring comprises a centric bore; wherein an auxiliary element is located radially outside said ring and extends no more than 180 in circumferential direction of said ring; and wherein the auxiliary element is arranged between the at least one side wall bearing the insert and the rotor, the auxiliary element being fixed to the at least one side wall bearing the insert.

2. The vane cell pump according to claim 1, wherein said auxiliary element comprises a width in radial direction of said rotor decreasing in circumferential direction starting from a central part.

3. The vane cell pump according to claim 2, wherein said auxiliary element has a length in circumferential direction which is greater than a width of said vanes in circumferential direction.

4. The vane cell pump according to claim 2, wherein said auxiliary element has a length in circumferential direction which is greater than a distance between two vanes in circumferential direction.

5. The vane cell pump according to claim 2, wherein in radial direction said auxiliary element has a predetermined distance to said ring.

6. The vane cell pump according to claim 2, wherein said auxiliary element protrudes out of said at least one side wall.

7. The vane cell pump according to claim 1, wherein said auxiliary element has a length in circumferential direction which is greater than a width of said vanes in circumferential direction.

8. The vane cell pump according to claim 7, wherein said auxiliary element has a length in circumferential direction which is greater than a distance between two vanes in circumferential direction.

9. The vane cell pump according to claim 7, wherein in radial direction said auxiliary element has a predetermined distance to said ring.

10. The vane cell pump according to claim 7, wherein said auxiliary element protrudes out of said at least one side wall.

11. The vane cell pump according to claim 1, wherein said auxiliary element has a length in circumferential direction which is greater than a distance between two vanes in circumferential direction.

12. The vane cell pump according to claim 11, wherein in radial direction said auxiliary element has a predetermined distance to said ring.

13. The vane cell pump according to claim 1, wherein in radial direction said auxiliary element has a predetermined distance to said ring.

14. The vane cell pump according to claim 1, wherein said auxiliary element protrudes out of said at least one side wall.

15. The vane cell pump according to claim 1, wherein a ring channel is located on a side of said ring opposite said rotor, said ring channel being connected to a high pressure region of the vane cell pump.

16. The vane cell pump according to claim 15, wherein a first sealing ring is located in said ring channel, wherein said first sealing ring generates a force onto said ring in a direction towards said rotor.

17. The vane cell pump according to claim 15, wherein a second sealing ring is positioned on a circumferential side of said ring.

18. The vane cell pump according to claim 1, wherein said rotor comprises a support ring bearing against said ring.

19. The vane cell pump according to claim 1, wherein the auxiliary element is in contact with the at least one side wall bearing the insert and the rotor.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) In the following, the invention is described on the basis of a preferred embodiment in connection with the drawings, showing:

(2) FIG. 1 is a schematic illustration of a cross-section of a vane cell machine and

(3) FIG. 2 is an enlarged section of an axial end part of a rotor of the vane cell machine.

DETAILED DESCRIPTION

(4) FIG. 1 shows schematically a vane cell machine 1 comprising a stator 2 and a rotor 3. The rotor 3 comprises a number of vanes 4, which are radially displaceable and bear on an inside 5 of the stator. Between each of two neighboring vanes 4 a work chamber 6 is positioned. At both axial ends the work chambers 6 are limited by a side wall 7 (FIG. 2).

(5) During a rotation of rotor 3 relative to stator 2 around an axis 8, the work chambers 6 increase and decrease their volume. During the increase of volume hydraulic fluid is sucked and during decrease of the volume of the work chambers 6 hydraulic fluid is pressurized and finally outputted under a higher pressure. The respective port for supply and delivery of the hydraulic fluid are not shown for sake of clarity.

(6) As can be seen in FIG. 1, the rotor 3 is placed eccentrically within stator 2.

(7) Side wall 7 accommodates an insert in form of a ring 9. Ring 9 comprises a centric bore 10. Rotor 3 comprises an axle 11 connected to a shaft 12. Ring 9 surrounds axle 11.

(8) Ring 9 is located in a groove 13 within side wall 7 and protrudes a bit out of side wall 7 in a direction towards rotor 3, e.g. by 0.5 mm.

(9) On a side of ring 9 opposite to rotor 3, there is a ring channel 14 which is connected by means of a bore 15 to a region 26 in which said work chambers 6 show a high pressure. This means that the ring channel 14 is loaded with this high pressure. This high pressure is used to press ring 9 towards rotor 3.

(10) Rotor 3 bears a support ring 21 contacting ring 9. One of ring 9 and support ring 21 can be used as a wear part which can easily be replaced if worn or necessary, because of other reasons.

(11) A first sealing ring 16 is positioned on the side of ring 9 opposite to rotor 3. The first sealing ring 16 seals the high pressure against a leakage in a direction towards a radial bearing 17 with which axle 11 is supported inside wall 7.

(12) A second sealing ring 18 is placed on a circumferential side of ring 9. The second sealing ring 18 is positioned as close as possible to rotor 3 so that most of the axial length of ring 9 is subjected to the high pressure acting radially inwardly.

(13) The first sealing ring 16 and the second sealing ring 18 are both made of an elastic material. Both sealing rings 16, 18 therefore generate a sort of pretension. Sealing ring 16 presses ring 9 against rotor 3 or more precisely against support ring 21 of rotor 3. Second sealing ring 18 centers ring 9 in the side wall 7.

(14) In addition to the first sealing ring 16, a spring or any other force generating means can be used to press ring 9 towards rotor 3.

(15) As mentioned above, rotor 3 is located eccentrically within the inside 5 of stator 2.

(16) In order to support the rotor 3 in a region in which the distance between the rotor 3 and the inside 5 of the stator 2 is largest, an auxiliary element 19 is provided, which is fixed to the side wall 7, for example, by one or two screws 20. The auxiliary element 19 is slightly curved. An inner radius of the auxiliary element 19 is slightly larger than an outer radius of ring 9. A radially outer side of auxiliary element 19 runs essentially parallel to the radially inner side of auxiliary element 19.

(17) The auxiliary element 19 can have a decreasing width in radial direction, i.e. it can have the form of a sickle or of a crescent moon (not shown). In any case, the auxiliary element 19 should extend in circumferential direction not more than over 180. In this case the ends in circumferential direction have a width tending against zero. Basically, it is sufficient when the auxiliary element 19 extends in circumferential direction at least over the width of the vane 4 in circumferential direction and preferably it should extend at least over a distance between two vanes 4 in circumferential direction.

(18) As can be seen in FIG. 2, the auxiliary element 19 protrudes out of side wall 7. The auxiliary element must protrude far enough that the rotor 3 cannot touch the side wall 7 and so that the ring 9 cannot get pinched inside the groove 13. It is sufficient when ring 9 and auxiliary element 19 protrude by 0.5 mm out of side wall 7.

(19) As can be seen in FIG. 2, there is a radial distance between ring 9 and auxiliary element 19. This distance makes it possible to accommodate second sealing ring 18. The sealing ring 18 can also be accommodated in the ring 9.

(20) The vane cell machine 1 can, for example, be used as a booster pump or circulation pump in a combination of pressure exchanger and booster pump, which can be used, for example, in a reverse osmosis system. In this case, there is always a rather high pressure within the vane cell machine. The booster pump sucks liquid at a pressure of for example 57 bar and outputs liquid with a pressure of 60 bar. The shaft 12 is usually sealed with a low pressure sealing only. Therefore, in the machine described sealing is achieved by the sealing ring 16 and, if necessary, by a third sealing ring 22 surrounding the support ring 21.

(21) The new ring 9, which is symmetric in all angular directions and comprises a centric bore 10, now is the only element which is necessary for the sealing function. The auxiliary element 19 serves as axial bearing and as blocking means against leakages.

(22) The machine 1 shown is simple in construction and can therefore be simply mounted.

(23) While the present disclosure has been illustrated and described with respect to a particular embodiment thereof, it should be appreciated by those of ordinary skill in the art that various modifications to this disclosure may be made without departing from the spirit and scope of the present disclosure.