PUMP ARRANGEMENT

Abstract

A pump arrangement for a drum or container pump, the pump arrangement including a pump housing; a drive shaft support tube received in the pump housing; and a drive shaft rotatably supported in the drive shaft support tube at a rotor side bearing and at a pump arrangement coupling, wherein the drive shaft runs freely between the rotor side bearing and the pump arrangement coupling, wherein the drive shaft runs through the at least one support ring that is fixed relative to the pump housing and that has an inner diameter that is greater than an outer diameter of the drive shaft and that is arranged between the rotor side bearing and the pump arrangement coupling.

Claims

1. A pump arrangement for a drum or container pump, the pump arrangement comprising: a pump housing; a drive shaft support tube received in the pump housing; and a drive shaft rotatably supported in the drive shaft support tube at a rotor side bearing and at a pump arrangement coupling, wherein the drive shaft runs freely between the rotor side bearing and the pump arrangement coupling, wherein the drive shaft runs through the at least one support ring that is fixed relative to the pump housing and that has an inner diameter that is greater than an outer diameter of the drive shaft and that is arranged between the rotor side bearing and the pump arrangement coupling.

2. The pump arrangement according to claim 1, wherein the inner diameter of the at least one support ring is greater than the outer diameter of the drive shaft supported therein so that the drive shaft does not contact the at least one support ring when the drive shaft runs without vibration.

3. The pump arrangement according to claim 1, wherein the at least one support ring is received in the drive shaft support tube or pressed into the drive shaft support tube.

4. The pump arrangement according to claim 1, wherein the at least one support ring is received in the seal module or pressed into the seal module.

5. The pump arrangement according to claim 1, wherein the rotor side bearing or the at least one support ring are made from a carbon or ceramic material.

6. The pump arrangement according to claim 1, wherein plural support rings are arranged along a length of the drive shaft support tube.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The invention is now described based on an advantageous embodiment with reference to drawing figures, wherein:

[0018] FIG. 1 illustrates a cross sectional view of the pump arrangement according to the invention including a drive shaft supported at a pump arrangement coupling and at a bearing in a seal module wherein the drive shaft runs with a clearance through a support ring that is arranged between the pump arrangement coupling and the bearing in the seal module;

[0019] FIG. 2 illustrates a detail of FIG. 1 showing a lateral cross-sectional view of the seal module with the support ring pressed into the drive shaft support tube; and

[0020] FIG. 3 illustrates an embodiment according to FIG. 2 and a lateral cross-sectional view showing the support ring pressed into the seal module.

DETAILED DESCRIPTION OF THE INVENTION

[0021] FIG. 1 illustrates a pump arrangement 1 including a tubular pump housing that receives a drive shaft 6 that is enveloped by a drive shaft support tube 5. A pump arrangement 1 of this type can be used for a drum or container pump. In this case the pump arrangement 1 is lowered into the container from a top side until a seal module 2 at a free end of the pump arrangement 1 reaches an area of the so-called pump sump. Rotating the drive shaft 6 including a rotor 9 which is connected torque proof to an end of the drive shaft 6 on a side of seal module 2 feeds a medium in the container between the wall of the pump housing 4 and the drive shaft support tube 5 in upward direction to an outlet and from there to a filling location. The drive is provided by a pump motor that is operatively connected with a pump arrangement coupling 3.

[0022] During operations of the pump motor and associated rotation of the drive shaft dry running can occur, thus a rotation of the drive shaft 6 without feeding a medium in the pump housing 4. Since an intermediary bearing between the pump arrangement coupling 3 and an end bearing 8 in the seal module 2 is omitted the drying running does not generate any frictional heat at the intermediary bearings so that the illustrated pump arrangement 1 can also be operated when running dry. When the drive shaft 6 starts vibrating during a dry run or under load, in a worse-case scenario vibrating in a resonance frequency range that leads to standing waves, a considerable deflection of the drive shaft can be caused so that the drive shaft impacts a wall of the drive shaft support tube 5.

[0023] This is prevented by the invention as illustrated in FIG. 2. In an area of the seal module 2 the drive shaft 6 is run through a support ring 7 which is configured as a hollow cylinder made from carbon or ceramic material or pressed into the drive shaft support tube 5. Only when the drive shaft 6 starts vibrating it impacts an inner surface of the support ring 7 wherein an inner diameter of the inner surface of the support ring is greater than an outer diameter of the drive shaft 6. Thus, any friction at the support ring 7 is prevented during smooth operations and excessive vibration of the drive shaft 6 is also prevented since the support ring 7 prevents any additional deflection beyond a deflection that is specified by the diameter of the inner surface of the support ring 7.

[0024] FIG. 3 illustrates a variation of the embodiment of FIG. 2 where the support ring 7 is not received in the drive shaft support tube 5 but in the seal module 2. Also here the support ring 7 is stationary whereas the drive shaft 6 is able to rotate freely. Only when the drive shaft 6 vibrates it comes in contact with the support ring 7 which prevents further increase of the vibration. Both solutions can be used individually or in combination when plural support rings 7 are being used.

[0025] The pump arrangement according to the invention can be operated dry without any risk without requiring bearings made from special materials or an encapsulated lubrication system.

REFERENCE NUMERALS AND DESIGNATIONS

[0026] 1 pump arrangement [0027] 2 seal module [0028] 3 pump arrangement coupling [0029] 4 pump housing [0030] 5 drive shaft support tube [0031] 6 drive shaft [0032] 7 support ring [0033] 8 bearing [0034] 9 rotor