EP0621759A1

EP0621759A1 - Dishwashing machine

Info

Publication number: EP0621759A1
Application number: EP94900044A
Authority: EP
Inventors: Jürgen MAGSIG; Reiner MÜNSTERER
Original assignee: Winterhalter Gastronom GmbH
Current assignee: Winterhalter Gastronom GmbH
Priority date: 1992-11-16
Filing date: 1993-11-16
Publication date: 1994-11-02
Anticipated expiration: 2013-11-16
Also published as: ATE175089T1; US5507877A; SK86594A3; WO1994010895A1; DE59309256D1; EP0621759B1; CZ171294A3; JPH07502924A

Abstract

PCT No. PCT/DE93/01089 Sec. 371 Date Jul. 14, 1994 Sec. 102(e) Date Jul. 14, 1994 PCT Filed Nov. 16, 1993 PCT Pub. No. WO94/10895 PCT Pub. Date May 26, 1994.A dishwashing machine is proposed which is considerably shorter in design than the previously used, continuously operated transport-dishwashers. In order permanently to reduce the consumption of water, energy and rinsing agent, the crockery in the individual crockery baskets is washed cyclical operation, the circuits of the rinsing apparatus being started up only in their respective time span within the wash program.

Description

Tableware SOÜlnasc-αi-αe

Description:

The invention relates to a dishwasher according to the preamble of claim 1.

State of the art:

Industrial machines of this type are generally used to clean plates, cups, cutlery and other crockery items, which are particularly required in the catering trade and related businesses.

Known industrial machines have a permanently running transport system for the crockery baskets or crockery boxes that hold the dishes to be cleaned. These are reciprocating push rods with pawls which engage in corresponding cross bars on the underside of the baskets when the push rods move in the transport direction. The items to be washed pass through different washing and rinsing zones as treatment stations, which can be separated from one another by plastic curtains. The washing or rinsing cycles within the dishwasher are also constantly in operation. The duration of a washing or rinsing process depends on the

Transport speed of the dishes and the length of the treatment stations. This way of working results, even if, as usual, there are only two treatment zones are a considerable space requirement for the dishwasher. On the one hand, each treatment zone must correspond to the distance traveled by a crockery basket during the washing or rinsing process and is therefore generally significantly larger than a basket length. On the other hand, when passing through a basket, the partition curtains are raised until it is passed under the partition curtain along its entire length. This does not result in a good delimitation of the different treatment zones within the dishwasher. As a result, hot vapors or spray mist escapes from one treatment zone into the other above or out of the machine, which is associated with a corresponding loss of energy and water and generally with poorer washing results. Inside the dishwasher there may be a carryover of lye from the so-called washing zone into the so-called rinse zone. This leads to an increased loss of wash liquor, which in turn has to be compensated for with the appropriate expenditure of material and energy. In order to better separate the washing zone from the rinsing zone, draining areas separated by curtains were again provided between the rinsing stations. However, this again leads to an increase in the space requirement of the machine.

It is also a considerable disadvantage that the flushing agent circuit for the individual flushing stations as well as the transport device is operated continuously. This is also the case when there are no more baskets on the transport device. In this case, the dishwasher runs without effective use, as a result of which the energy consumed is uselessly wasted, which increases the operating costs accordingly. In some cases, this disadvantage could be partially offset by so-called auto-timers. Nevertheless, the entire washing and rinsing mechanism in question was started. From DE-U-1 928 642 an industrial dishwasher with automatic dish transport has also become known, in which the dishes are automatically introduced into the interior of the dishwasher and the transport is subsequently interrupted. While the dishes in the baskets resting in the baskets are at a standstill, they are first washed using a program switch and then rinsed. As a result, the position of the dishes remains unchanged during the washing and rinsing process and is only subsequently removed from the machine.

Such an operation of the dishwasher has the advantage that the space requirement of the machine can be significantly reduced compared to the previously described dishwasher design. Due to the stationary position of the crockery basket, the dwell time of the crockery inside the machine increases until all processing operations are completed.

Object and advantages of the invention:

The invention has for its object to propose a dishwasher that has a minimal space requirement with optimal washing performance.

This object is solved by the features of claim 1. Advantageous and expedient developments of the dishwasher specified in claim 1 are contained in the subclaims.

1

The basic idea of the invention is that optimum performance, a minimum consumption of energy, water and chemical additives as well as a minimum space requirement can only be achieved by an optimized construction of a dishwasher can be achieved. As a result, in the dishwasher according to the invention, the items to be washed do not pass through the machine as usual at a slow speed, but are quickly drawn into them and remain in the effective areas or treatment zones for a long time in order to then quickly leave the machine. This results in long contact times during the treatment process and short throughput times in the movement process. Due to the space-saving design due to the working principle of the dishwasher according to the invention, it can be used in almost every scullery of the catering and hotel industry. The operation of the dishwasher is extremely economical and environmentally friendly due to the intermittent transport process. In particular, for example. water consumption and rinse aid consumption are halved, while a third less detergent is needed for the washing process. This results in a high saving effect on energy and resources, which not least also results in low electrical connection values of the machine.

The invention is based on the knowledge that a stationary arrangement during the washing process results in an optimization of the operating resources mentioned with a minimum of space requirement. This method of stationary treatment of dishes during the cleaning process, which is initially known per se, is optimized according to the present invention in that the washing zone is immediately followed by the rinsing zone, so that the removal or extension time of the dishes can be used directly for the rinsing process. As a result, the rinse zone can also be kept very short, which benefits the space requirement of the machine.

The immediate spatial proximity of the rinsing zone downstream of the washing zone enables on the one hand the optimal treatment of the dishes during the washing process, the crockery basket either stands up during this phase or at least performs a slightly oscillating back and forth movement. The subsequent subsequent rinsing process is then carried out when the crockery basket is removed, the rinsing agent with its high proportion of fresh water simultaneously serving to regenerate the wash liquor for the main wash cycle.

The dishwasher according to the invention is accordingly equipped with a program control by means of which the items to be washed can be positioned in the cleaning area of the dishwasher, the execution of a washing program with the crockery basket largely at rest and the washing process being switched off after the main washing cycle has taken place. The energy loss to the environment is significantly reduced in that the liquid circuit for the main washing process - hereinafter referred to as "washing process" - is switched off as soon as the transport movement is carried out. The actual washing process is only started when the wash ware is positioned in its washing position. A flexible separating curtain already covers the entire feed opening, effectively shielding the interior of the dishwasher, which is designed as a washing chamber or treatment chamber. The washing zone of the rinsing chamber itself can be adapted to the size of a conventional dish rack floor plan, or can also be dimensioned larger, since the items to be washed are at rest during the washing process. Since the transport only starts again after the washing process has ended, there is no longer any need for a draining area between the washing zone and the rinsing zone. However, it is advisable to make a short drain between the processing steps to reduce the carryover of washing liquor into the rinse zone. As a result, the space requirement of the dishwasher according to the invention is optimized to a minimum. The measure that the liquid circuit is only put into operation for the washing process as well as for the rinsing process only during the respective treatment process, the energy, water and cleaning agent consumption is significantly reduced.

Since the rinsing process is generally less time-consuming than the washing process, it is particularly advantageous that the rinsing process is carried out after the washing process so that the dishes pass through the rinsing zone during the rinsing process and the extension time is thus used for the rinsing process.

The dishwasher according to the invention works in the main washing process with wash liquor, which are arranged in one or more collecting trays below the washing zones and which are transported to the lower and upper washing nozzles by means of circulation pumps. The wash liquor remains in the machine for a large number of subsequent washing processes and is cleaned of dirt in the usual way and partly regenerated by fresh water. There is therefore no high water consumption for the wash liquor.

In contrast, at least one additional collecting container is required for the rinsing process, in which fresh water is prepared for the rinsing process. In a further development of the invention, two such rinsing systems are provided, which are charged with fresh water and heated. For example, only the rinse circuit at the outlet of the dishwasher can be provided with special rinse aid.

In order to reduce the energy consumption of the dishwasher as a whole, a thermally insulated collecting container is therefore used to prepare the washing water for the washing process - 7 -

provided that due to the spatial proximity to the rinse zone during the rinsing process is also filled with rinse liquid. This results in a dilution or regeneration of the wash liquor due to the rinse liquid, in particular not provided with rinse aid.

A further reduction in energy consumption can also be achieved in that different washing or rinsing steps can be carried out at different temperatures, with the corresponding liquids having different temperatures being taken up in different collecting containers.

An embodiment of the invention is shown in the drawings and explained in more detail in the following description.

Show it

1 shows a schematic longitudinal section through a dishwasher according to the invention,

2 shows a schematic cross section of the dishwasher according to FIG. 1,

3 shows a perspective view of the dishwasher according to FIGS. 1 and 2,

4: a perspective view of the washing zone, rinsing zone and a drive system,

5 is a perspective view of the rinse arrangement and

6: a path-time comparison diagram between a dishwasher according to the invention and a known process sequence. The dishwasher 1 according to FIGS. 1, 2 and 3 has an interior designed as a washing chamber 2 or treatment chamber 2, which is divided into a washing zone 5 and a subsequent rinsing zone 7. The imaginary parting plane 9 symbolically drawn in FIG. 1 separates the two zones lying spatially next to one another. In the washing zone 5, as shown in FIGS. 1 and 2, there is a crockery basket or crate 3 to be cleaned which is to be cleaned, hereinafter referred to as "basket". The arrangement of the crockery basket 3 in the washing zone 5 according to FIG. 3 is shown in FIG. 4. The crockery basket 3 is filled with crockery 4.

Above and below the crockery basket 3 there are e.g. four upper (25) and three lower (26) washing arms 25, 26, to which a plurality of washing nozzles 6 and 6 'are fastened, the upper washing arms 25 being able to be arranged laterally offset from the lower washing arms 26, in order to provide spaces between the dishes better grasp. In the exemplary embodiment, about five to seven washing nozzles 6, 6 'are provided on each washing arm 25, 26.

The rinsing chamber 2, which is designed as a rinsing zone 7 in its left end region, has in this region a plurality of upper (30, 31) and lower (32, 33) rinsing arms which, like the washing arms, are at a certain lateral distance from one another and on which rinsing nozzles 8 , 8 'are attached.

The crockery basket 3 rests on two transport devices 10, 11 which are spaced next to one another. The transport devices designed as conveyor belts 10, 11 in the present example run around two deflection rollers 12, 13 and over two guide rollers 14. In the area of the left-hand side shown in FIGS. 1 and 4 Deflection roller 13 is the Conveyor device driven by an electric motor 16 via a belt part 15.

The rinsing chamber 2 is closed in its entrance area 17 and its exit area 18 by means of two flexible, double strip curtains 27, 28 (FIG. 1). In front of the entrance 17 an already prepared next dish rack 19 is waiting for the processing operation, while behind the exit 18 the dish rack 20 last washed can still be seen in FIG. 1. In front of the crockery basket 3 located in the washing chamber 2, a limit switch 21 is shown, which stops the transport of the crockery basket 3. The entire dishwasher rests on a machine frame 22. A control and maintenance flap 38 can be provided in the front area.

1 to 4, the conveyor belts 10, 11 of the transport device for the crockery basket 3 are driven via a drive shaft 23 and a drive wheel 24. The limit switch 21 is located next to the crockery basket 3, so that it can pass without bumping. The washing nozzles 6, 6 'are attached to the washing arms 25, 26, which also serve as feed lines.

Below the washing zone 5 there is a thermally insulated washing liquor container 29, which serves as a collecting container for the washing liquor and from which the washing liquor collected during the washing process is pumped to the individual washing nozzles 6, 6 'via cleaning units (not shown).

As shown in FIGS. 1, 4 and 5, the rinsing zone 7 is arranged immediately after the washing zone 5. The rinsing zone 7 contains two upper rinsing arms 30, 31 lying next to one another, on the underside of which three or four lying next to each other Rinse nozzles 8 are attached. Likewise, two further lower rinse arms 32, 33 are provided, which also have three or four rinse nozzles 8 '. As can be seen from FIG. 5, the rinse zone contains two separate rinse systems with separate collecting containers 34, 35 for the rinse liquid, which are led to the respective rinse arms via feed lines 36, 37. The rinse arms 30, 32 and the rinse arms 31, 33 are to be regarded as belonging together, which forms a kind of vertical curtain in the rinse zone. With two rinse systems, different temperature levels for the rinse liquid can be set. In particular, only one of the rinsing systems, preferably the rear 35, 31, 33, can also be provided with a rinsing agent, which leads to the saving of additional chemical substances.

The liquid from the two rinsing containers 34, 35 also reaches the washing liquor container 29 during the rinsing process and regenerates the washing liquor due to the high fresh water content. The rinse system is always supplied with fresh water.

The rinsing process in such a dishwasher is as follows:

A crockery basket 19 is brought to the entrance area 17 of the washing chamber 2. After the machine has started, the washing basket 19 is picked up by the conveyor belts 10, 11 of the transport device and conveyed into the washing chamber 2 in the direction of the arrow P. The main washing process is carried out in a position of the crockery basket which is located directly below or above the washing nozzles 6, 6 '(see FIGS. 1, 4). This position is set by the actuation of the limit switch 21 by the crockery basket, the conveyor belts 10, 11 being stopped. Up to this point, the washing nozzles 6, 6 'are out of operation. The Curtain 28 has fallen back into its essentially vertical starting position after retracting the crockery basket 19. With this type of side closure, the working temperature and water loss can be reduced. A washing process or washing program now begins, in which the washing liquid or rinsing liquid heated in the washing suds container 29 is conveyed via the cleaning devices into the washing arms 25, 26 and from there into the washing nozzles 6, 6 '. The washing time is determined by the washing program. The washing basket 3 is designed in such a way that, due to its permeable areas, in particular in the lower and upper areas, it does not hinder the washing process.

After the washing program in washing zone 5 has ended, a short draining phase can be inserted. Then the two conveyor belts 10, 11 start moving again and the crockery basket 3 passes through the rinsing zone 7 at a slow speed, the rinsing nozzles 8, 8 'of which are in operation while the crockery basket 3 is being passed through. Different rinsing liquids can be fed from the two collecting containers 34, 35 into the two respective rinsing arms 30, 32 and 31, 33, respectively. Subsequently, the crockery basket 3 leaves the washing chamber 2 via the outlet 18, the next crockery basket 19 being able to be fed through the inlet 17 if necessary.

The washing or rinsing process is thus only in operation when a crockery basket 3 is actually in the washing position 5 or rinsing zone 7. In contrast to the previous continuously operating dishwashers, the intermittent transport process enables a significantly smaller structure to be achieved with considerable savings in energy, water and detergent consumption. The difference from the previous mode of operation of a continuously operating system is shown schematically in FIG. 6 using a path-time diagram of two flushing processes. The 45 ° line shows a conventional rinsing process, the step-shaped line arranged to the left of it shows a rinsing process according to the invention.

Both washing processes start at time t _Q , the crockery basket in question being in position SQ. In a flushing process according to the invention, the flushing position s ^ is first approached as quickly as possible. The time until the time t- ^ is required for this. During the subsequent rinsing period D _g , the crockery basket 3 remains in its position s ^ until the time t2 and beyond the end of the washing process t2 until the time t3, at which a short dripping phase has ended. (t3 - t2 = dripping phase). The crockery basket is then conveyed through the rinsing zone 7 at a very slow speed, the beginning of which is at point S2 and the end of which is at point S3. At time t ^ the crockery basket finally reaches the machine outlet and is in position s ^.

In the previous mode of operation, the crockery baskets were continuously transported through a long entrance zone until they entered the rinsing zone at point s ^ '. This long inlet zone is necessary because with continuously running crockery baskets the dividing curtains at the entrance to the rinsing zone are constantly slightly raised, which means that rinsing water and vapors could escape if the entrance area is too short. After entering the washing zone at point Si ', the crockery basket runs through the washing zone up to point S2' in a continuous system at constant speed. Here it enters a long transition zone until it enters the rinse zone at point 33 '. This wide transition zone between the washing zone and the rinsing zone is in turn necessary because all the spray nozzles are at the same time are in operation, ie even while the crockery baskets are lifting the dividing curtains. The prevention of a carryover of lye into the rinse zone therefore requires this long transition area up to the point S3 '. At point s ^ 'the crockery box emerges from the rinse zone. After complete exit from the rinse zone, it finally reaches its end position s ^ 'in the machine outlet. On the basis of the two diagrams it can be clearly seen that a flushing method according to the invention enables a machine of considerably shorter design and actual operating time. The cycle-wise processing of the crockery baskets is made clear by the kinked characteristic curve, while the previous continuous mode of operation is reflected in the straight characteristic curve. The two characteristics are designed for the same maximum performance. As can be seen in the diagram, the advantage that the machine runs through the machine simultaneously during the continuous operation of several crockery baskets is offset in a flushing method according to the invention by a considerably shorter processing time for the individual flushing basket.

The many advantages of a flushing method according to the invention are particularly pronounced when the machine is not operating at full capacity. While in the continuous process all the washing units must also be in continuous operation for the passage of an individual crockery basket, the washing circuit of a dishwasher according to the invention only works during the actual washing process. The main wash nozzles are switched off before entering the rinse zone. This saves a lot of water, energy and detergent.

A further energy saving results from the targeted temperature gradation in the two collecting containers 34, 35 for the rinsing process. This can be a targeted Aftertreatment of the dishes can be carried out with rinse liquid at different temperatures and provided with rinse aid.

The invention also provides that after the discharge of a crockery basket at the end of the washing process, the transport device continues to run for a predetermined time interval. If a crockery basket is fed again within this time interval, the process described above is repeated. The transport device also stops after the time interval has elapsed without the addition of a crockery basket. In this case the dishwasher must be started again manually.

Due to its lateral position, the transport device consisting of the two conveyor belts 10, 11 enables unimpeded access in the central area or on the underside of the crockery baskets by means of the washing or rinsing nozzles. A corresponding open design of the lower area of the crockery basket enables lower access to the crockery. Furthermore, any crockery baskets with a suitable floor plan can be used, since webs on the underside for engaging pawls are no longer required for a conventional pull rod.

Depending on the intended use, the washing nozzles 6, 6 'or the rinsing nozzles 8, 8' can be designed to be pivotable, in order to achieve good accessibility to the dishes and thus an improvement in the washing result, particularly in the case of dirt which is difficult to remove.

The invention is not restricted to the exemplary embodiment described and illustrated. Rather, it also includes all professional developments within the scope of the inventive concept mentioned in claim 1.

Claims

Claims:

1. Dishwasher for cleaning dishes, especially in the commercial sector, with a washing chamber (2) which comprises a washing or rinsing zone and in which a plurality of washing or rinsing nozzles (6, 8) for washing or After-rinsing process is provided, with a transport device (10, 11) which extends longitudinally through the washing chamber (2, 11) for transporting the dishes (4) and with a control device for the timing of the washing and transport process, an input opening (28) to the washing chamber ( 2) the dishwasher (1) is followed by a first washing zone (5), to which the dishes (4) can be transported by means of the transport device (10, 11), characterized in that the dishes (4) during the washing process in the area of the washing zone ( 5) lingers and that the washing zone (5) is immediately followed by a rinsing zone (7), the rinsing process being carried out with the washing device (6, 6 ') switched off during the transport of the dishes (4).

2. Dishwasher according to claim 1, characterized in that between the washing process in the washing zone (5) and the subsequent rinsing process in the rinsing zone (7) a short temporal dripping phase (t = tß - t2) is provided.

3. Dishwasher according to claim 1, characterized in that a thermally insulated collecting container (29) is provided for receiving the washing liquid in the dishwasher.

4. Dishwasher according to claim 1, characterized in that different washing and / or rinsing intervals are provided with mutually graduated temperatures and that for the washing and / or rinsing liquids different temperatures different collecting containers (34, 35) are provided.

5. Dishwasher according to claim 1, characterized in that a preferably operated by the crockery basket (3) limit switch (21) is provided in the region of the washing zone (5), the signal of which turns off the transport device (10, 11) as soon as the dishes ( 4) in the washing zone (5) in the washing position.

6. Dishwasher according to claim 1 or 5, characterized in that the transport device (10, 11) comprises two conveyor belts (10, 11) or conveyor chains or the like arranged laterally in the washing chamber (2).

7. Dishwasher according to claim 1, characterized in that the washing zone (5) has approximately a length which corresponds at least to the length of a crockery basket (3).

8. Dishwasher according to claim 1 or 7, characterized in that the rinsing zone (7) provided in the outlet region of the rinsing chamber (2) comprises a length for the rinsing process which corresponds to approximately half the length of the washing zone (5).

9. Dishwasher according to claim 1, characterized in that the washing (6, 6 ') and / or the rinsing nozzles (8, 8') swing the water jet back and forth and in particular are designed to be pivotable.

10. Dishwasher according to claim 1, characterized in that the drive for the crockery basket (3) during the washing process and / or the rinsing process oscillates back and forth or is oscillatingly movable.

11. Dishwasher according to claim 1, characterized in that the inlet and / or the outlet openings for feeding or discharging a crockery basket (19, 3, 20) by means of a loosely hanging, flexible, preferably double curtain (28, 27) is closed.

12. Dishwasher according to claim 1, characterized in that during the feeding of the crockery basket (3) into the washing zone (5) of the rinsing chamber (2) the washing process is started and the crockery basket (3) lingers in the washing zone (5) that the Rinsing process in the rinsing zone (7) immediately downstream of the washing zone (5) during the further transport of the dishes (4) on the

Transport device (10, 11) takes place, the dishes (4) also being able to remain in the post-rinse zone (7).

13. Dishwasher according to claim 1, characterized in that the transport device (10, 11) after the discharge of the dishes (4) continues a predetermined time interval to accommodate new dishes to be cleaned in the washing chamber (2).

14. Dishwasher according to claim 13, characterized in that after the exit of the cleaned dishes (4) after a time interval without feeding a new dishes basket (19) the transport device (10, 12) is stopped.

15. Dishwasher according to claim 13, characterized in that the inflow of a new crockery basket (19) into the washing chamber (2) takes place during the removal of the treated crockery basket (3, 20).