Pump device

Abstract

The invention relates to a pump device for operating vacuum drainage systems and for pumping sewage, in particular on watercrafts. This pump device comprises a drive device having a drive shaft that comprises a first shaft end and a second shaft end and can be rotated by means of the drive device. The pump device further comprises a centrifugal pump which has at least one impeller that is connected in a torque-proof manner to the drive shaft in the region of the first shaft end.

Claims

1. A system including a pump device (10) for operating a vacuum drainage systems and for pumping sewage, comprising a drive device (20) having a drive shaft (22) that comprises a first shaft end (22a) and a second shaft end (22b) and can be rotated by means of the drive device (20), a centrifugal pump (30) having at least one impeller (32) that is connected in a torque-proof manner to the drive shaft (22) in a region of the first shaft end (22a), a vacuum pump (40) having at least one rotor (42) that is connected in a torque-proof manner to the drive shaft (22) in a region of the second shaft end (22b), each of the centrifugal pump (30) and the vacuum pump (40) being connected to the drainage system, the vacuum pump (40) being provided with a first port on a suction side thereof and a second port on a pressure side thereof, the centrifugal pump (30) being provided with third and fourth ports, the first port of the vacuum pump (40) on the suction side thereof being connected indirectly to the drainage system via a buffer storage, the buffer storage (70) being kept under vacuum by the vacuum pump (40) and sewage can be pumped out of the buffer storage (70) by the centrifugal pump (30), and the third port of the centrifugal pump (30) being on a pressure side thereof and discharging the pumped sewage, the fourth port of the centrifugal pump (30) being on the suction side thereof and sucking sewage into the centrifugal pump (30), the centrifugal pump (30) being in direct connection to the drainage system by the fourth port on the suction side of centrifugal pump (30) and in fluid line connection to the buffer storage, the direct connection of the centrifugal pump to the drainage system below the first port of the suction side of the vacuum pump (40) allowing discharging sewage contained in the buffer storage, and a cutting device (50) having a rotatable cutting knife, wherein the rotatable cutting knife (52a) is connected in a torque-proof manner to the drive shaft (22) in the region of the first shaft end (22a) upstream of the impeller (32) and downstream of the buffer storage.

2. The system according to claim 1, characterized in that the cutting device (50) is configured to comminute material passing the cutting device into a grain size of smaller than or equal to 4 mm to 8 mm.

3. The system according to claim 1, characterized in that the vacuum pump (40) is designed as a rotary vane pump or a liquid ring vacuum pump.

4. The system according to claim 1, characterized in that the impeller (32) of the centrifugal pump is connected to the drive shaft (22) in a region of the shaft ends (22a, 22b) via switchable couplings (44a and 44b).

5. The system according to claim 1, characterized in that the vacuum pump (40) is provided on the suction side thereof with a filter (46) which prevents solids having a grain size of greater than 1 mm from getting into the vacuum pump (40).

6. The system according to claim 1, characterized in that the vacuum pump (40) is provided on the suction side thereof with a condensate separator (45) which prevents suctioned water droplets or condensate from a suction line and the upstream buffer storage (70) getting into the vacuum pump (40).

7. The system according to claim 1, characterized in that the pump device (10) is connected on the pressure side thereof to a collection tank (60).

8. The system according to claim 1, characterized in that a cleaning opening (12) is arranged on a suction side of the pump device (10), which cleaning opening is reversibly closed with a cleaning opening cover (14).

9. The system according to claim 1, characterized in that the buffer storage (70) is kept under vacuum by means of the vacuum pump (40), wherein sewage can be pumped out by means of the centrifugal pump (30).

10. The system according to claim 1, characterized in that the centrifugal pump (30) is provided with a dry run protection that protects a mechanical seal in a case of a dry run of the centrifugal pump (30).

11. The pump device system of claim 1, characterized in that the cutting device (50) has a stationary cutting ring that lies outside the rotatable cutting knife in a radial direction.

12. The system according to claim 1, characterized in that the cutting device (50) has a stationary cutting ring.

13. The system according to claim 12, characterized in that a maximum value for grain sizes of solid particles allowed to pass through is set by the stationary cutting ring.

14. The system according to claim 12, characterized in that the rotatable cutting knife (52a) is arranged upstream of the stationary cutting ring in an axial direction of the drive shaft (22) with regard to flow direction.

15. The system according to claim 12, characterized in that the stationary cutting ring has at least one cutting surface arranged cross-wise to an axial direction, over which the rotatable cutting knife is arranged to rotate.

16. The system according to claim 12, characterized in that an arrangement of the rotatable cutting knife and stationary cutting ring is such that the rotatable cutting knife functions as a first stage of mechanical processing and the stationary cutting ring functions as a second stage of mechanical processing.

17. The system according to claim 1, characterized in that the rotor (42) of the vacuum pump (40)is connected to the drive shaft (22) in a region of the shaft ends (22a, 22b) via switchable couplings (44a and 44b).

18. The system according to claim 1, wherein the buffer storage (70) has a first inlet in communication with the drainage system, a second inlet as a first portion on the suction inlet in communication with the vacuum pump (40) and an outlet as the fourth port on the suction side of the centrifugal pump (30), the buffer storage configured to allow a vacuum to be generated therein using the second inlet in order to draw sewage into the buffer storage from the first inlet, with the vacuum existing above the sewage drawn into the buffer storage, and the centrifugal pump is adapted for pumping sewage from the buffer storage via the outlet, including in instances where a level of sewage in the buffer storage reaches a level where sewage is sucked into the second inlet by the vacuum pump.

19. A drainage device on a watercraft, comprising a system and a pump device (10) according to claim 1.

Description

(1) The present invention is explained in more detail with reference to the accompanying drawing figures. The terms left, right, above and below used here refer to an alignment of the drawing figures with human readable reference numbers. In the figures:

(2) FIG. 1 shows a schematic cross-sectional illustration of an embodiment of the present invention;

(3) FIG. 2 shows a schematic illustration of a flow diagram of an embodiment of the present invention;

(4) FIG. 3 shows a schematic illustration of a further embodiment of the present invention;

(5) FIG. 4 shows a schematic illustration of a further embodiment of the present invention.

(6) FIG. 1 clearly shows the compact construction of a pump device 10 according to the invention. The pump device 10 according to the invention has a drive device 20 as the central component. In this embodiment, the drive device 20 is configured, for example, as an electric motor. The output shaft of the electric motor forms at the same time the drive shaft 22 of the pump device 10 so that the drive device provides the torque necessary for operating the pump device 10.

(7) The drive shaft 22 of the drive device 20 protrudes from the drive device 20 from both sides thereof. In this manner, the two shaft ends 22a as the first shaft end and 22b as the second shaft end become visible and are provided to be utilized for the torque provided by the drive device 22 at these two shaft ends 22a and 22b. The impeller 32 of a centrifugal pump 30 is arranged at the first shaft end 22a of the drive shaft 22 in the region of said shaft end and is connected to the drive shaft 22 in a torque-proof manner. Likewise, a cutting device 50 is connected in a torque-proof manner to the drive shaft 22 in the region of the first shaft end 22a of the drive shaft 22. If a torque is transmitted to the drive shaft 20, the impeller 32 of the centrifugal pump 30 and also the cutting device 50 and the rotor 42 of the vacuum pump 40 rotate.

(8) The cutting device 50 has a rotatable cutting knife 52 which is divided into a rotatable cutting knife 52a and a stationary cutting ring 52b. The stationary cutting ring 52b lies outside of the rotatable cutting knife 52a with regard to the radial direction, and lies behind the rotatable cutting knife 52a with regard to the axial direction of the drive shaft 22. By selecting an adequate cutting ring 52b, the maximum value for the grain sizes of solid particles allowed to pass through can be set.

(9) Furthermore, upstream of the cutting device 50, a cleaning opening 12 is provided. This cleaning opening 12 is closed with a cleaning opening cover 14 which can be reversibly closed. If now clogging or reduced output of the centrifugal pump 30 is detected, an inspection of the centrifugal pump 30 and also of the cutting device 50 can be carried out via the cleaning opening 50. If it is detected during this inspection that solids have deposited in this region, these solids can be removed through the cleaning opening 12 without any problem so that the continued operation of the cutting device 50 and also the centrifugal pump 30 is ensured. Between the centrifugal pump and the drive device there is a dry run protection 31 for protecting the mechanical seal in the case of a dry run of the centrifugal pump.

(10) The rotor 42 of a vacuum pump 40 is fixed at the second shaft end 22b of the drive shaft 22. As is schematically shown in FIG. 1, the vacuum pump 40 is preferably a rotary vane pump, wherein the rotor 42 is arranged eccentrically in the housing of the vacuum pump 40. Not shown are the individual design features of the rotor 42, in particular the necessary rotary vanes and the spring elements for moving the respective rotary vane in the radial direction, and how they rest against the housing of the vacuum pump 40. The rotor 42 is also connected to the drive shaft 22 in a torque-proof manner so that in the embodiment of FIG. 1, the rotor 42, the cutting device 50 and the impeller 32 of the centrifugal pump 30 all rotate with the identical speed of the drive device 20. With regard to controlling the pump device 10 of the present invention, thus, only a signal and power supply is needed for the drive device 20 which, in the same manner, drives all three components, namely the rotor 42 of the vacuum pump 40, the impeller 32 of the centrifugal pump 30 and also the cutting means 52 of the cutting device 50 with the same speed.

(11) FIG. 2 schematically illustrates a flow diagram using a pump device 10 according to the invention. The drive shaft 22 is illustrated here in dashed lines according to its functionality. A drive device 20, here likewise implemented as a motor, in particular as an electric motor, is connected in a torque-transmitting manner to the vacuum pump 40 and also to the centrifugal pump 30 and the cutting device 50 via the drive shaft 22. In other words, the drive device 20 drives all three components together, thus the cutting device 50, the centrifugal pump 30 and the vacuum pump 40. The centrifugal pump 30 and the cutting device 50 are arranged here in the region of a first shaft end 22a, and the vacuum pump 40 is arranged on an opposite second shaft end 22b of the drive shaft 22. The pump device 10 can be implemented as illustrated in FIG. 1, for example.

(12) By means of the vacuum pump 40, a vacuum is generated in the connected pipe system until a stable vacuum is reached. After reaching the desired vacuum in the pipe system, the pump device switches off and the system is ready for operation. Through the discharge points (toilets, showers and drains), an air-sewage mixture LU/AB is discharged in intervals into the pipe system, which mixture accumulates before the suction opening of the centrifugal pump. When the sewage level before the centrifugal pump has reached a predefined height, or the vacuum in the system is no longer sufficient to constantly operate the system, the pump device switches on again. The sewage before the centrifugal pump is comminuted and discharged, and the air taken in is removed by the vacuum pump until a stable vacuum is established again so as to reliably operate the connected vacuum drainage system. Furthermore, upstream of the vacuum pump 40 there are a filter 46 and a condensate separator 45 which prevent that solid particles, water droplets or condensate above a certain size, in particular greater than 1 mm, can get into the vacuum pump 40.

(13) In order to be able to drive or switch off the vacuum pump in a specific manner, a coupling 44b is provided in the drive shaft 22. Through the coupling 44b it is possible to switch on or also to switch off the torque transmission from the drive device 20 to the vacuum pump 40. Thus, the vacuum pump 40 becomes switchable, thereby further increasing the flexibility of use of a pump device 10 according to the invention. Furthermore, there is a coupling 44a in the drive shaft 22 between drive and centrifugal pumps.

(14) FIG. 3 shows a variation of the embodiment of FIG. 2. The components used therein and having the same effect are designated with the same reference numbers, for which reason a detailed description thereof is omitted. Rather, only the differences of the two embodiments are explained below.

(15) In contrast to FIG. 2, a plurality of differences can be seen in the embodiment of FIG. 3. Firstly, the sewage AB is not pumped into the surroundings or a connected sewer system; rather, a collection tank 60 is provided into which the discharge takes place. The collection tank 60 is dimensioned here in such a manner that, at least temporarily, an isolated operation of the pump device 10 in a drainage system can be used. The collection tank can be an already existing integral part of an existing drainage system to which the pump device 10 according to the invention is connected.

(16) In FIG. 4, a further embodiment of a pump device according to the invention is schematically illustrated. Here too, identical reference numbers are used for identical components, which is the reason why an explanation thereof is not repeated here.

(17) In contrast to the embodiments of FIG. 2 and FIG. 3, a buffer storage 70 is provided in this embodiment of FIG. 4. The buffer storage 70 is connected to the drainage system and can receive sewage AB therefrom. In order to receive the sewage from the drainage system, a vacuum is generated in the buffer storage 70. This vacuum is generated via the vacuum pump 40 which is driven via the drive device 20, in particular via the drive shaft 22. In other words, the buffer storage 70 is constantly kept under a vacuum so that in the case of sewage accumulating in the drainage system, the sewage, conveyed by the vacuum, can flow into the buffer storage 70. A slope for conveying the sewage AB is not necessary in this embodiment. Thus, a sewage level will arise in the buffer storage 70 which level advantageously lies below the port on the suction side of the vacuum pump 40. If the level rises over time in the buffer storage 70, discharge from the buffer storage 70 will be necessary once a certain sewage level is reached.

(18) When the pumping device switches on, the centrifugal pump 30 is driven via the drive device 20, in particular the drive shaft 22 thereof, and discharging of sewage from the buffer storage 70 takes place. The sewage AB can be discharged into the environment or into a connected sewer system or into a storage tank as known from the embodiment of FIG. 3.

(19) In this embodiment too, advantageously, a cutting device 50 is provided which is arranged upstream of the centrifugal pump 30. Accordingly, comminuting takes place only during the discharge from the buffer storage 70 so that the buffer storage still contains non-comminuted material. For example, this can be utilized such that coarse suspended solids deposit in the buffer storage during the detention time and cannot get into the subsequent circuit. In such an embodiment, the buffer storage 70 can be used as a primary rough treatment stage.

(20) It goes without saying that the above illustrated embodiments are only examples. Of course, these examples can be freely combined with one another so that individual components can be combined into a new embodiment, provided that this is technically reasonable.

(21) All features and advantages arising from the claims, the description and the drawing, including constructional details, spatial arrangements and methods steps, either in themselves or in many different combinations, can be essential for the invention.

REFERENCE LIST

(22) 10 Pump device 12 Cleaning opening 14 Cleaning opening cover 20 Drive device 22 Drive shaft 22a First shaft end 22b Second shaft end 30 Centrifugal pump 31 Dry run protection 32 Impeller 40 Vacuum pump 42 Rotor 44a Coupling 44b Coupling 45 Condensate separator 46 Filter 50 Cutting device 52 Rotatable cutting means 52a Rotatable cutting knife 52b Stationary cutting ring 60 Collection tank 70 Buffer storage AB Sewage LU Air AB/LU Sewage-air mixture