Vacuum toilet and method of flushing a vacuum toilet

Abstract

The invention relates to a vacuum toilet with a toilet bowl (10), a transfer tank (12), and a flushing water container (14). The flushing water container (14) is designed and connected such that a flushing process is triggered when the toilet is actuated, wherein flushing water is conveyed into the toilet bowl (10) from the flushing water container via a first flushing water line (16) using positive pressure, which is applied in the flushing water container (14) by a compressed air source (21), and the transfer tank (12) is designed and connected such that after the flushing process, a suction material is suctioned out of the toilet bowl (10) and into the transfer tank (12) using negative pressure which is applied to the transfer tank (12). The invention is characterized in that flushing water is conveyed into the transfer tank (12) by means of a second flushing water line (18), which is supplied by the first flushing water line and which has a controllable valve (Q07), when the controllable valve (Q07) opens the second flushing water line (18) in order to flush the transfer tank (12).

Description

[0001] The present invention relates to a vacuum toilet comprising a toilet bowl, a transfer tank, and a flush water reservoir, as well as a method for flushing a vacuum toilet. The flush water reservoir is designed and connected such that when the toilet is activated, a flushing process is triggered in which, by means of overpressure applied in the flush water reservoir by a compressed air source, flush water is conveyed from it into the toilet bowl via a first flush water line. The transfer tank is designed and connected such that, following the flushing process, the fluid extracted from the toilet bowl is drawn into the transfer tank by means of a negative pressure applied to the transfer tank.

[0002] Vacuum toilets are used, for example, as toilets in vehicles (such as rail vehicles, airplanes, watercraft, buses, etc.) and offer the possibility of suctioning waste material from the toilet bowl into a transfer tank using a vacuum and finally conveying it into a wastewater reservoir.

[0003] Such a vacuum toilet is known, for example, from DE 20 2002 101 760 U1 or from EP3047077B1. The vacuum toilet comprises a toilet bowl, a transfer tank, and a flush water reservoir. The flush water reservoir is designed and connected such that when the toilet is activated, a flushing process is triggered in which, by means of overpressure created in the flush water reservoir by a compressed air source, flush water is transported from it into the toilet bowl via a first flush water line. The transfer tank is designed and connected such that, following the flushing process, the waste from the toilet bowl is drawn into the transfer tank by means of a vacuum applied to the transfer tank. In such a vacuum toilet, impurities can accumulate in the transfer tank, which can eventually lead to a blockage of the vacuum toilet.

[0004] From FI110538B a vacuum toilet system with a flush water tank is known, which is connected on the inlet side to a compressed air source and a flush water source and is connected on the outlet side to a toilet bowl.

[0005] ES2366504A1 discloses a toilet with a vacuum evacuation system, comprising a toilet bowl and a wastewater tank, wherein a shut-off valve is located between the outlet of the toilet bowl and the inlet of the tank.

[0006] From DE202013009406U1, a mobile sanitary unit, previously known, is designed for the recycling of greywater. A freshwater tank is connected to a freshwater-consuming unit, and a greywater discharge line from this unit leads to a greywater tank. From the greywater tank, a line leads to a greywater-consuming unit, and another line leads to a wastewater tank. A valve is arranged in the connecting line between the freshwater-consuming unit and the greywater tank, and another valve is arranged in the connecting line between the greywater tank and the wastewater tank. Simultaneous opening of both valves is prevented.

[0007] It is therefore an object of the present invention to provide a vacuum toilet in which the impurities in the transfer tank are reduced in order to prevent clogging of the vacuum toilet.

[0008] This problem is solved by a vacuum toilet with the features of claim 1. Advantageous embodiments are defined in the dependent claims.

[0009] According to the present invention, a second flushing water line is provided, which is fed by the first flushing water line. This second flushing water line has a controllable valve that can release or block the flow of flushing water in the second flushing water line.

[0010] When the controllable valve opens the second rinse water line, rinse water is pumped into the transfer tank and the transfer tank is rinsed.

[0011] Within the scope of the present invention, the term "suction mass" refers to the mass that is removed from the toilet bowl when it is flushed. The suction mass may contain flush water, feces, and other components.

[0012] Preferably, the second flushing water line branches off from the first flushing water line via a T-shaped connection. The flushing water from the first flushing water line flows, for example, into the vertical branch of the T-shaped connection and splits into two flushing water streams within the T-shaped connection. One flushing water stream, which continues to form the flushing water stream of the first flushing water line, flows, for example, through the left horizontal branch, and the second flushing water stream, which forms the flushing water stream of the second flushing water line, flows out through the right horizontal branch of the T-shaped connection.

[0013] Preferably, the transfer tank has a flushing nozzle with multiple nozzle openings, supplied by the second flushing line. This flushing nozzle arrangement in the transfer tank ensures that as many areas as possible, and ideally all, of the transfer tank's inner wall are flushed.

[0014] In one embodiment of the present invention, the first flushing water line is also provided with a controllable valve. The two controllable valves on the flushing water lines can be controlled independently of each other. This allows the flushing water flow to be directed along different paths. If the valve of the first flushing water line is open and the valve of the second flushing water line is closed, flushing water can flow from the flushing water reservoir into the toilet bowl, but not into the transfer tank. If the valve of the first flushing water line is closed and the valve of the second flushing water line is open, flushing water can flow into the transfer tank, but not into the toilet bowl. If both valves are open, flushing water can flow into the transfer tank and into the toilet bowl.

[0015] In a further embodiment of the present invention, the controllable valve of the second flushing water line is designed as a 3 / 2-way valve. This allows flushing water to flow either from the first flushing water line into a continuation of the first flushing water line into the toilet bowl, or from the first flushing water line via the second flushing water line into the transfer tank.

[0016] Preferably, the controllable valves are solenoid valves. According to further preferred embodiments, the vacuum toilet has an electronic control unit.

[0017] This control unit is programmed to control the compressed air source and the controllable valve of the second rinsing water line in such a way that the transfer tank is rinsed under predefined conditions.

[0018] In one embodiment of the present invention, the control device is configured to check, as a predetermined condition, the number of flushing cycles of the toilet bowl after the last flush of the transfer tank. After a predetermined number of flushing cycles, the control device controls the compressed air source and the controllable valve on the second flushing water line such that a separate flushing cycle is performed for the transfer tank.

[0019] In an alternative embodiment of the present invention, the control device is configured to check, as a predetermined condition, the number of flushing cycles of the toilet bowl after the last flush of the transfer tank. After a predetermined number of flushing cycles, the control device controls the compressed air source and the controllable valve on the second flushing water line such that a flushing cycle for the transfer tank is performed simultaneously with the next flushing cycle of the toilet bowl.

[0020] As a preferred alternative, the control unit is configured to check for the expiration of a predetermined regular time interval as a predefined condition. After this time interval has elapsed, the control unit controls the compressed air source and the controllable valve of the second rinsing water line in such a way that a rinsing process is carried out for the transfer tank.

[0021] In a further alternative embodiment of the present invention, the control unit is configured to check, as a predefined condition, whether a frost drain signal is present for the vehicle. The frost drain signal is triggered, for example, before the train's operating hours are over, in order to empty all water-carrying lines and tanks. If this signal is present, the control unit controls the compressed air source and the controllable valve of the second flushing water line such that the drained flushing water is used to perform a flushing process for the transfer tank.

[0022] This ensures that the transfer tank is cleaned before prolonged periods of non-use of the vacuum toilet, in order to prevent the hardening of deposits in the transfer tank.

[0023] The invention is explained below with reference to an embodiment illustrated in the figures. The figures show: Figure 1 shows a schematic diagram of the vacuum toilet with a controllable valve on the second flush water line, Figure 2 shows a schematic diagram of the vacuum toilet with a controllable valve on the second flush water line and a controllable valve on the first flush water line, Figure 3 shows a schematic diagram of the vacuum toilet with a controllable valve on the second flush water line, which is designed as a 3 / 2-way valve.

[0024] A vacuum toilet will be referred to below with reference to the Figures 1 to 3The vacuum toilet comprises a toilet bowl 10, a transfer tank 12, and a flush water tank 14. The flush water tank 14 has a level sensor B02, which is coupled to a valve Q06. If the level sensor B02 indicates that there is too little flush water in the flush water tank 14, the valve Q06 is opened and the flush water tank 14 is filled via a flush water line 20 coming from a fresh water reservoir.

[0025] The flush water tank 14 is designed and connected such that a flushing process is triggered when the toilet is activated. Compressed air is supplied via a compressed air line 22 from the compressed air source 21, through a flushing valve Q01 and a valve 24, into the interior of the flush water tank 14. This forces flush water from the flush water tank 14 through a first flushing line 16 into the toilet bowl 10. To complete the flushing process, the supply of compressed air to the flush water tank 14 is stopped, whereupon the position of the valve 24 changes. There is still overpressure in the flush water tank 14. Due to the changed position of the valve 24, the vent line 26 is accessible, through which the overpressure in the flush water tank 14 can be released.

[0026] The transfer tank 12 is designed and connected such that, following the flushing process, the inlet valve Q05 opens and the suction mass from the toilet bowl 10 is drawn into the transfer tank 12 by means of a vacuum applied to it. The inlet valve Q05 then closes again, creating positive pressure in the transfer tank 12. Subsequently, the outlet valve Q04 opens, and the suction mass in the transfer tank 12 is conveyed by the positive pressure applied to the transfer tank 12 into a wastewater reservoir connected to the transfer tank 12. The negative and positive pressures in the transfer tank 12 are controlled by the pressure valve Q02 and the vacuum valve Q03.

[0027] A second rinse water line 18 is connected so that it is fed by the first rinse water line 16. The second rinse water line 18 has a controllable valve Q07 that can open or close the rinse water flow in the second rinse water line 18. When the controllable valve Q07 opens the second rinse water line 18, rinse water is pumped into the transfer tank 12 and the transfer tank 12 is rinsed.

[0028] The second flushing water line 18 branches off from the first flushing water line 16 via a T-shaped connection 17. The flushing water from the first flushing water line 16 flows, for example, into the vertical branch of the T-shaped connection 17 and splits into two flushing water streams within the T-shaped connection 17. One flushing water stream, which continues to form the flushing water stream of the first flushing water line 16, flows, for example, through the left horizontal branch, and the second flushing water stream, which forms the flushing water stream of the second flushing water line 18, flows out through the right horizontal branch of the T-shaped connection 17.

[0029] In Figure 2Figure 1 shows an embodiment of the present invention in which the first flushing water line 16 is also provided with a controllable valve Q08. The two controllable valves Q07 and Q08 can be controlled independently of each other. This allows the flushing water flow to be directed along different paths. If the valve of the first flushing water line Q08 is open and the valve of the second flushing water line Q07 is closed, flushing water can flow from the flushing water reservoir 14 into the toilet bowl 10, but not into the transfer tank 12. If the valve of the first flushing water line Q08 is closed and the valve of the second flushing water line Q07 is open, flushing water can flow into the transfer tank 12, but not into the toilet bowl 10. If both valves Q07 and Q08 are open, flushing water can flow into the transfer tank 12 and into the toilet bowl 10.

[0030] In Figure 3Figure 1 shows a vacuum toilet in which the controllable valve of the second flushing water line Q07 is designed as a 3 / 2-way valve. This allows flushing water to flow either from the first flushing water line 16 into the toilet bowl 10 via a continuation of the first flushing water line, or from the first flushing water line 16 into the transfer tank 12 via the second flushing water line 18.

Claims

1. Vacuum toilet with a toilet bowl (10), a transfer tank (12) and a flushing water tank (14), and a first flushing water pipe, wherein the flushing water tank (14) is designed and connected to the toilet bowl in such a way that, when the toilet is actuated, a flushing process is triggered in which, with the aid of an overpressure created in the flushing water tank (14) by a compressed air source (21), flushing water is conveyed from the latter via the first flushing water line (16) into the toilet bowl (10), and wherein the transfer tank (12) is designed and connected to the toilet bowl in such a way that, following the flushing process, suction mass is sucked out of the toilet bowl (10) into the transfer tank (12) with the aid of a negative pressure applied to the transfer tank (12), characterized by a second flushing water line (18) fed by the first flushing water line and having a controllable valve (Q07), through which flushing water is conveyed into the transfer tank (12) when the controllable valve (Q07) opens the second flushing water line (18) in order to flush the transfer tank (12).

2. Vacuum toilet according to claim 1, characterized in that the second flushing water line (18) branches off from the first flushing water line (16) via a connection in T-piece form (17).

3. Vacuum toilet according to claims 1 and 2, characterized in that the transfer tank has a flushing nozzle fed by the second flushing line with several nozzle openings arranged in a distributed manner.

4. Vacuum toilet according to claims 1, 2 and 3, characterized in that the first flush water line (16) is also provided with a controllable valve (Q08) and the two controllable valves can be controlled independently of one another, so that, when the valve of the first flush water line (Q08) is open and the valve of the second flush water line (Q07) is closed, flush water can flow from the flush water tank (14) into the toilet bowl (10), but not into the transfer tank (12), and, if the valve of the first flush water line (Q08) is closed and the valve of the second flush water line (Q07) is open, flush water can flow into the transfer tank (12) but not into the toilet bowl (10), and, if both valves are open, flush water can flow into the transfer tank (12) and into the toilet bowl (10).

5. Vacuum toilet according to claim 1, characterized in that the controllable valve of the second flush water line (Q07) is designed as a 3 / 2-way valve which either directs flush water from the first flush water line (16) into a continuation of the first flush water line into the toilet bowl (10) or directs flush water from the first flush water line (16) via the second flush water line (18) into the transfer tank (12).

6. Vacuum toilet according to the preceding claims, characterized in that the controllable valve (Q07) of the second flush water line and, if dependent on claim 4, the controllable valve (Q08) of the first flush water line is a solenoid valve or solenoid valves.

7. Vacuum toilet according to the preceding claims, characterized in that it has an electronic control device which is prepared in terms of programming to control the compressed air source (21) and the controllable valve of the second flushing water line (Q07) in such a way that the transfer tank (12) is flushed under predetermined conditions, such as the number of flushing operations of the toilet bowl after the last flushing of the transfer tank or the expiry of a predetermined regular time interval or whether a frost drain signal is present.

8. Vacuum toilet according to claims 4 and 7 or 5 and 7, characterized in that the control device is set up to check, as a predetermined condition, the number of flushing operations of the toilet bowl (10) after the last flushing of the transfer tank (12) and, after a predetermined number of flushing operations, to control the compressed air source (21) and the controllable valve on the second flushing water line (Q07) in such a way that a separate flushing operation is carried out for the transfer tank (12).

9. Vacuum toilet according to claims 1, 4 and 7, characterized in that the control device is set up to check the number of flushing operations of the toilet bowl (10) after the last flushing of the transfer tank (12) as a predetermined condition and, after a predetermined number of flushing operations, to control the compressed air source (21) and the controllable valve on the second flushing water line (Q07) in such a way that a flushing operation for the transfer tank (12) is carried out simultaneously with the next flushing operation of the toilet bowl (10).

10. Vacuum toilet according to claims 1, 4 and 7 or 1, 5 and 7, characterized in that the control device is set up to check the expiry of a predetermined regular time interval as a predetermined condition and, on expiry, to control the compressed air source (21) and the controllable valve on the second flushing water line (Q07) in such a way that a flushing process for the transfer tank (12) is carried out.

11. Vacuum toilet according to claims 1, 4 and 7 or 1, 5 and 7, characterized in that the control device is set up to check, as a predetermined condition, whether a frost drain signal is present and, if a signal is present, to control the compressed air source (21) and the controllable valve of the second flushing water line (Q07) in such a way that a flushing process for the transfer tank (12) is carried out with the flushing water that is drained.

12. A method for flushing a vacuum toilet with a toilet bowl (10), a transfer tank (12) and a flushing water tank (14), and a first flushing water pipe with the steps: Triggering of a flushing operation when the toilet is actuated, in which, with the aid of an overpressure applied in the flushing water tank (14) by a compressed air source (21), flushing water is conveyed from the latter into the toilet bowl (10) via a first flushing water line (16), and Following the flushing process: Suction of a suction mass from the toilet bowl (10) into the transfer tank (12) using a vacuum applied to the transfer tank (12), characterized in that the transfer tank (12) is flushed by feeding flushing water into the transfer tank (12) through a second flushing water line (18) fed by the first flushing water line by means of a controllable valve (Q07) when the controllable valve (Q07) opens the second flushing water line (18).

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