FI87307C - FOERBAETTRAT OEVERSTROEMNINGSSYSTEM - Google Patents

Description

! 87307

Improved overflow system. - Förbättrat överströmnings-system.

The invention relates to a mechanical article washing machine for intermittent washing of loading sets, each loading being subjected to a washing step where it is irrigated with a washing solution from a liquid distribution system and the solution is collected in a tank located below the loading and then in a rinsing step. washing tank, the tank being provided with an overflow pipe to limit the height of the surface of the liquid therein.

In such machines, the total volume of the washing solution is normally considerably larger than the volume of the hot rinsing water. Usually, the overflow pipe is a vertical pipe extending through the bottom of the tank, terminating in an upwardly directed opening. The liquid in the tank assumes the height of this opening.

After each washing step, the washing solution is stored in a tank to await recirculation to wash the next load.

*. Some of the solution remains in the recycling unit to form part of the distribution system. Each step reduces the cleaning efficiency of the solution, ‘‘ firstly because part is sucked into the effluent to be removed and secondly because it is partially diluted as the rinsing water falls into it. This::: is not too critical, because when recirculating the solution, a base-based and / or surfactant-based detergent from a known dosing system is added.

However, it can be estimated that the dirt-water removed from the load falls into the tank with the solution used. After ; · - several loads have been washed, the accumulation of dirty water in the 2 87307 tank means that the solution is too dirty for further use and needs to be replaced, which is a waste of detergent, energy and time. The rinsing water falling into the tank washes some of the dirty water down into the overflow, but as it falls to the surface of the solution it tends to be immediately down into the overflow without substantially mixing with the solution body. Thus, not much dirt is removed and the time before the total solution change has to be done is not optimally increased.

In addition, there are additional disadvantages to the system because the rinsing water is quite hot (typically about 85 ° C) due to necessity. The wash solution, which is pre-stored in the tank awaiting recirculation, must be kept at the desired temperature (normally about 55 ° C to 60 ° C) by thermostatic heating. is wasted when run off immediately through overflow.

♦ · ·

We have now found that these disadvantages can be eliminated by a machine according to the invention, which is characterized by the things set forth in the characterizing part of claim 1.

r.:.: It is known to equip a washing machine with a siphon tube in the middle of a rotating drum, according to DE 2 241 329. It is also known to provide a dishwasher with a liquid level control comprising an overflow pipe with a siphon connected to a chamber where the pressure triggers a pressostat, as e.g. disclosed in EP 152 893 and EP 253 655. It is also known to provide a liquid dose dispenser for a laundry with a siphon outlet pipe having an open end at the bottom of the dispenser chamber (US 2991911). Various auxiliary devices for washing machines, including a water level regulator with an overflow pipe and a top cover pipe for flap operation, are disclosed in EP 003 451, GB 1 510 750, EP 128 070 and DE 3 215 501.

However, it has been believed that the siphon overflow of the present invention has never been utilized in a tank of a mechanical washing machine as described above in order to provide a more efficient operation and a simple, inexpensive and efficient energy saving means.

In a preferred embodiment of the invention, the first opening of the siphon part is located close to the bottom of the container. Preferably, the siphon portion of the overflow pipe includes an inverted U-shaped fold at its top.

In an alternative, particularly preferred embodiment, the siphon part comprises a cover placed on the upward open end of the overflow pipe.

The present invention will now be better explained by the following specific embodiment, in which: Figure 1 shows a mechanical washing machine of a known type, provided with a known shape of an overflow pipe.

Figure 2 shows a preferred overflow pipe according to the present invention, for use in the machine illustrated in Figure 1.

Figure 3 shows a particularly preferred overflow pipe according to the present invention, again for use in the machine shown in Figure 1.

4 87307

Figure 1 shows a known mechanical article washing machine 1 comprising a chamber 3 divided into a washing space 5 and a tank 7 placed above. In use, the loading 9, including, for example, the containers 11, is placed in a frame 13 which is supported inside the washing space.

The fluid distribution system, which includes freely rotatable spray arms 15,17 located above and below the loading, respectively, is provided with fluid passages 19 resp. 21. The liquid in question is used to irrigate the load, in the form of jets 23,28 which exit through nozzles 27,29 in the spray arms. As usual, the nozzles are positioned at an angle so that the jets cause the spray arms to rotate (arrows A, B).

Once the loading has been set in, the first washing step is started, where a considerable volume of warm washing solution is used to irrigate the loading. This solution then drips (31) into the tank and is recirculated repeatedly during the washing step by means of a pump 32 and a recirculation system (not shown). The volume of the body of the washing solution 33 held in the tank is limited by the overflow pipe 35. When the liquid surface 36 * * reaches all the height of the overflow open end 37 amount of current draining arrow C direction. Typically, the tank has a volume of about 50 liters.

After the washing step, the loading is soaked in about 3 liters of very hot water (about 85 # C) supplied from the main tubes through a heating system (not shown). The rinsing water enters through the annular openings 38,39, concentrically through the openings 19 resp. With 21. It is applied for loading from jet arms 41,42, which are substantially similar to arms 15,17 and are thus freely rotatable in the direction of arrows A, B. Like the washing solution, the rinsing water drips into the tank, related to the solution already kept in it.

5 87307 In practice, with the open end of the overflow tube facing upwards, the rinsing water tends to dissipate directly down the overflow tube without thoroughly mixing with the solution in the tank. In addition, the higher temperature of the rinsing water, and thus its lower density, also tends to prevent it from mixing with the main part of the solution.

Because the solution is kept in a wash tank for later reuse, it is kept warm by a thermostatic heater (not shown). The very high temperature of the rinsing water, despite its relatively small volume, means that if it could be thoroughly mixed with the main part of the solution in the tank, it could significantly contribute to the heat content therein, thus reducing the amount of energy consumed by the thermostat. However, as mentioned, in practice, the rinsing water is lost considerably immediately. This is the problem which the present invention eliminates.

After the rinsing step, the washed loading is changed to a new soiled loading and the whole process is repeated again.

In this successive step, the washing solution is taken from the tank (via filter 43) by a pump. It is delivered outwardly in the direction of arrow D, the usual dosage unit (not shown), within the recirculation system, where it is loaded again with cleaning agent and is recycled to the feed system (suihkuvar ret 15,17). This next washing step then proceeds as well as the first. A second rinsing step is then performed, and again the solution in the tank is further diluted by a small amount. This process is repeated until the washing solution is so soiled due to the accumulation of dirt water that it is no longer usable for practical purposes.

Referring now to Figure 2, in one embodiment, the invention provides an alternative overflow tube 44 for use in place of the known tube 35 in the machine of Figure 1 6 87307. In this case, this new overflow pipe is provided with an inverted U-shaped bend 45 in its upper region.

In use, the liquid level in the container rises until it reaches the upper part 46 of the fold. It allows the solution to freely enter the downward part of the overflow pipe through the first opening 47. Any additional water that falls on the surface of the liquid in the tank will cause some of the water to flow down into the overflow pipe. The second smaller opening 48 located at the top of the U-shaped fold of the overflow pipe is a small vent hole. It serves to prevent the pressure differential between the inside of the overflow pipe and the liquid from the surface. Such a pressure difference could otherwise cause the container to be subjected to a patch effect, i. drain itself down into the overflow pipe until the liquid level has reached the level of the first orifice 47. Since the opening 47 is permanently located below the surface of the liquid in the tank, the water falling into the washing solution must undergo considerable mixing with the main part of the solution before any is lost down to the overflow. In practice, this means that more dirt is removed from the tank downstream of each overflow stage, so more washing / rinsing operations can be performed before the solution in the tank has to be completely renewed. In addition, more heat is stored in the rinsing water, leading to significant energy savings: ·. use.

In another particularly preferred embodiment shown in Figure 3, the second overflow pipe is provided with an upwardly facing open end 51 on which a cylindrical cover 53 is placed so that the cover and the tube together define an annular first opening 55. A second smaller opening 56 is provided on the cover. it is immediately apparent that the operation of this device is analogous to that shown in connection with Figure 2.

Claims (4)

A mechanical washing machine (1) for the purpose of periodically washing loading batches, each loading being subjected to a washing step where it is wetted (23, 28) with a washing solution coming from a liquid distribution system and the solution is collected in a container (7). located below the loading (9, 11), and thereafter in a rinsing step, where it is wetted with the rinsing water as droplets in the washing solution already present in the container, the container being provided with an overflow tube (35) for limiting the level of the liquid surface (36). characterized in that the overflow pipe is provided with a siphon part with a first opening (47, 55) at the end of the pipe located substantially below said liquid surface and a second, smaller air opening (48, 56) above the liquid surface, for balancing the pressure in the upper part of the overflow pipe and preventing the siphon action above the liquid, and in this way effecting that the rinsing water is is mixed with the washing solution before any water at all leaves via the overflow pipe. Machine according to Claim 1, characterized in that the first opening in the siphon portion is located near the bottom of the container. «#» I 3. Machine according to claims 1-2, characterized in that the tile part of the siphon part includes an inverted U-shaped knee (45) in V: the overflow pipe (44). «« · Machine according to claims 1-2, characterized in that the siphon part belongs to a lid (53) d) acting on the open orifice opening (51) in said overflow pipe (49).