1. Field of the Invention
The present invention relates to a method of transporting wash ware through a conveyor dishwasher, and to a conveyor dishwasher in which the wash ware is transported continuously.
2. Description of the Background Art
WO 00/53076 A1 discloses a conveyor dishwasher which comprises a washing zone and a rinsing zone, items which are to be cleaned being conveyed through the dishwasher and being sprayed with a cleaning solution within the washing zone. The cleaned crockery is rinsed in the zone following the washing zone. The dishwasher is driven such that it operates cyclically, in which case, within an operating cycle, a transporting belt is driven at a normal speed and cleaning solution is fed to the washing zone, whereas clean water is fed to the rinsing zone. Within an idling cycle, the conveying arrangement, in the form of a transporting belt, is stopped and the supply of clean water to the rinsing zone is interrupted.
The dishwasher known from WO 00/53076 A1 comprises a washing zone, a rinsing zone and a transporting belt for conveying items through the dishwasher as well as feed arrangements for feeding cleaning solution to the washing zone and also nozzles for spraying rinsing water within the rinsing zone. Also provided is a control arrangement for controlling the dishwasher, the control arrangement controlling the transporting arrangement cyclically. A timer for controlling the washing cycles achieves the situation where, while items are conveyed in the conveying direction on the transporting belt, cleaning solution is simultaneously fed to a washing zone and clean water is conveyed to the rinsing zone. During a pause cycle, the transporting belt, with the items accommodated thereon, is at a standstill, while the feed of clean water to the rinsing zone remains interrupted.
According to this solution, with the exception of a transporting belt arranged at the inlet and at the outlet, the conveyor dishwasher has a single transporting belt passing through it. Movement through all zones, be it the washing zone, the cleaning zone or a rinsing zone, takes place at the same speed. This solution proposes cyclic, non-continuous transportation of the items which are to be cleaned in the conveyor dishwasher, rapid transportation resulting in short durations of action of the cleaning fluid, whereas long durations of action can be achieved when the transporting arrangement is stopped. In other commercially available machines, the wash ware is transported continuously through the machine. In these machines, the slowest processing zone predetermines the transporting speed for the rest of the zones in the machine.
In conveyor dishwashers, for example the rinsing step requires a minimum quantity of water to be applied to the wash ware within the shortest period of time in order to produce a sufficiently thick film of water to wash away particles. At lower transporting speeds of a transporting arrangement, for example of a transporting belt moving continuously through the conveyor dishwasher, too much rinsing water is consumed in relation to the number of wash-ware items in each case because the wash ware remains for a relatively long period of time in the clean-water rinsing region.
It is therefore an object of the present invention to provide a conveyor dishwasher in which, with a continuous transporting speed of a transporting arrangement, it is possible to optimize the duration of dishwashing, rinsing or drying phases.
Following the solution proposed according to the invention, in one of the treatment zones of a conveyor dishwasher, a direct-action spray device for introducing a cleaning medium, or a dishwashing system, is moved relative to the direction in which the wash ware is transported through the conveyor dishwasher. The relative movement of the direct-action spray system for a cleaning medium, or of a dishwashing system, for applying clean water and dishwashing liquid can take place both in and counter to the direction in which the wash ware is transported through the treatment zones of the conveyor dishwasher.
According to an aspect of the solution proposed according to the invention, a spray system or dishwashing system which acts from both sides on the wash ware transported through the conveyor dishwasher may be accommodated on a carriage, which, by means of a separate, independent drive, can be displaced relative to the transporting arrangement, for example a circulating transporting belt. According to this aspect, limit switches can sense the displacement distance in both directions of the carriage, which accommodates the dishwashing system, spray system, which can be moved relative to the transporting arrangement, or the direct-action spray system. The limit switches, which are provided at the end points of the respective displacement distance in the displacement direction of the carriage, are connected to a machine controller. The first limit switch can sense, for example, the time taken for the wash ware to reach the first limit switch. The transporting speed of the wash ware can be calculated therefrom, by the machine controller. In dependence on the transporting speed determined, the separate, carriage-driving drive can then be operated and for example the clean-water dishwashing system, which is accommodated on the carriage, can be displaced either in or counter to the direction in which the wash ware is transported through the conveyor dishwasher. This advantageously achieves the situation where conveyor dishwashers can make considerable savings in terms of clean water and heat energy required for heating up the clean water and also detergents, i.e. chemicals introduced. The first limit switch senses not just the transporting speed of the wash ware through the conveyor dishwasher but also, at the same time as the separate drive for the carriage is operated, a pump which delivers heated-up clean water and operates a solenoid valve. The machine controller optimizes the movement speed of the carriage in dependence on the value which has been calculated in the machine controller for the speed at which the wash ware is transported through the conveyor dishwasher.
If, for example, the carriage is arranged within the rinsing zone of the conveyor dishwasher, the carriage accommodates clean-water rinsing systems which wet the wash ware from the top side and the underside. If the carriage passes into a position which can be established by a second limit switch, the separate drive can be reversed as a result of the second limit switch being reached, in which case the carriage and the clean-water rinsing systems accommodated therein resume their starting position in the region of the first limit switch. At the same time as the now rinsed wash ware reaches the second limit switch, the rinsing function can be switched off, i.e. the machine controller controls the solenoid valve for supplying clean water to a pump provided in the rinsing zone of a conveyor dishwasher.
In a further aspect of the invention, a direct-spray system or a dishwashing system, for example a clean-water rinsing system, can be pivoted about a pivot axis within a corresponding treatment zone of the conveyor dishwasher. It is also the case with this variant that the system is then assigned separately operable drives relative to the wash-ware-accommodating transporting arrangement of the conveyor dishwasher. According to this variant, the pivoting movement of the dishwashing system or the direct-spray system is sensed by detectors. In dependence on the wash ware reaching a first detector, the pivoting drive is activated and, once the wash ware has passed through the corresponding treatment zone, detected by a second detector arranged at the end of the treatment zone, can also be switched off again. In respect of, for example, supplying clean water to such a dishwashing system, reference is made to what has been discussed in relation to the first variant.
As a result of the wash ware reaching the first detector, it is also possible, according to this variant, for the machine controller to calculate the speed at which the wash ware is transported through the conveyor dishwasher. The movement speed, i.e. the angular speed of the spray systems about the pivot axis, can be predetermined in optimized fashion in dependence on the value calculated for the transporting speed.
The above variants of the idea on which the invention is based, regardless of whether they are used in a dishwashing zone, a pump-action rinsing zone or a clean-water rinsing zone, can be used to achieve respectively durations of action as well as quantities of water and quantities of detergent which, on the one hand, reduce the quantity of water consumed by the conveyor dishwasher, on the other hand limit the heat energy to the amount which is absolutely necessary and, finally, considerably reduce the introduction of chemicals into the dishwasher proposed according to the invention.
Further scope of applicability of the present invention will become apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description.
The present invention will become more fully understood from the detailed description given hereinbelow and the accompanying drawings which are given by way of illustration only, and thus, are not limitive of the present invention, and wherein:
The illustration according to
The preliminary cleaning zone 3, according to the illustration in
The preliminary cleaning zone 3 has a washing zone 4 arranged downstream of it. Instead of the one washing zone 4 which is illustrated in
The at least one washing zone 4 of the conveyor dishwasher 1 has the pump-action rinsing zone 5 arranged downstream of it. The pump-action rinsing zone 5 contains a top pump-action rinsing system 33 and a bottom pump-action rinsing system 34. A return means 35 extends into a tank 36 from the bottom pump-action rinsing system 34. A pump 37 takes in cleaning fluid from the tank 36 and delivers it, in turn, to the top pump-action rinsing system 33 and to the bottom pump-action rinsing system 34. It is also the case that the pump 37 arranged in the pump-action rinsing zone 5 is connected to the machine controller 55 of the conveyor dishwasher 1.
The pump-action rinsing zone 5 has a clean-water rinsing zone 6 arranged downstream of it.
A top clean-water rinsing system 41 and a bottom clean-water rinsing system 42 are arranged within the clean-water rinsing zone 6. By virtue of the clean-water rinsing systems 41, 42, the wash ware 10 accommodated on the transporting arrangement 11 is transported through the clean-water rinsing zone 6 in the transporting direction 9. In that variant of the conveyor dishwasher 1 which is illustrated in
It is also the case that, following the concept proposed according to the invention, it is possible for the direct-action spray systems, with which for example a more highly concentrated detergent is introduced in the treatment zones 3, 4 or 5, to be arranged within the respective treatment zone such that they can likewise be moved relative to the transporting arrangement 11. Furthermore, it is also conceivable for drying fans 51 arranged in the drying zone 7 to be moved relative to the wash ware 10 transported in the transporting direction 9, for example to be pivoted about a pivot axis.
The idea on which the invention is based will be explained in more detail hereinbelow using the example of a clean-water rinsing zone 6 of the conveyor dishwasher 1. As can be gathered from
As seen in the transporting direction 9 of the wash ware 10, a first signal transmitter 53 is located in the entry region to the clean-water rinsing zone 6. The end point of the displacement distance of the transporting carriage in the displacement direction 39, counter to the transporting direction 9, is designated 44. As seen in the direction 9 in which the wash ware 10 is transported through the conveyor dishwasher 1, a second signal transmitter 54 is located in the exit region of the clean-water rinsing zone 6. The end point of the displacement distance 40 in the direction 9 in which the wash ware 10 is transported through the conveyor dishwasher 1 is designated 43. The clean-water rinsing systems 41, 42 accommodated on the displaceable carriage 49 are connected to a pump 46 via a movable water feed 48. The pump 46, which for its part is connected to the machine controller 55, has a solenoid valve 47 arranged upstream of it, it likewise being possible for the solenoid valve to be actuated by the machine controller 55. From the clean-water rinsing zone 6, a return means 45 extends into the tank 36, which is assigned to the pump-action rinsing zone 5 and into which runs excess clean water from the clean-water rinsing zone 6. The clean water which is fed to the top clean-water rinsing system 41 and the bottom clean-water rinsing system 42 by the pump 46 may be pre-heated, i.e. brought to the desired temperature in a boiler, or it may be cold water.
It should be mentioned, for the sake of completeness, that arranged downstream of the clean-water rinsing zone 6, according to the illustration in
Following passage through the at least one washing zone 4 and the pump-action rinsing zone 5, the point in time at which the cleaned wash ware 10 enters into the clean-water rinsing zone 6 is sensed by the first signal transmitter 53. The first signal transmitter 53 is connected to the machine controller 55. In the machine controller 55, the point in time at which the cleaned wash ware 10 enters into the clean-water rinsing zone 6, sensed by the first signal transmitter 53, is used to calculate the transporting speed of the transporting arrangement 11 at which the wash ware 10 is transported through the conveyor dishwasher 1 in the transporting direction 9. The separate drive 50, which drives the carriage 49, is brought into operation at the same time as wash ware 10 is detected by the first signal transmitter 53. The drive 50 moves the carriage 49, with the clean-water rinsing systems 41 and 42 accommodated thereon, in the displacement direction 39, i.e. counter to the transporting direction 9 of the wash ware 10, through the clean-water rinsing zone 6. By virtue of the first signal transmitter 53, the solenoid valve 47 and the pump 46 are brought into operation via the machine controller 55, in which case the clean-water rinsing systems accommodated on the carriage 49 are supplied with clean water. The speed at which the carriage 49 is moved can be adjusted optimally, in respect of the clean-water consumption, in dependence on the transporting speed of the wash ware 10 in the transporting direction 9, this speed being determined in the machine controller 55. This ensures that precisely the quantity of clean water which is necessary for completely washing away particles from the wash ware 10 is introduced into the clean-water rinsing zone 6 of the conveyor dishwasher 1.
Once the carriage 49, with the clean-water rinsing systems 41, 42 accommodated thereon, reaches the front end point 44 in the displacement direction 39, counter to the transporting direction 9 of the wash ware 10, the drive 50 assigned to the carriage 49 is reversed and displaces the carriage 49 in the displacement direction 40, i.e. in the transporting direction 9 of the wash ware 10, until the rear end point 43 has been reached. Once the rear end point 43 has been reached, and when the wash ware 10 is detected by the second signal transmitter 54, the solenoid valve 47 is brought into operation by the machine controller 55 and the clean-water delivery pump 46 is switched off, this likewise being initiated by the machine controller 55.
The cleaned, and now rinsed, wash ware 10 enters, from the clean-water rinsing zone 6, into the drying zone 7, in which the wash ware leaving the clean-water rinsing zone 6 is dried and, if appropriate, cooled.
The illustration according to
A further variant of the idea on which the invention is based will be explained using the example of the clean-water rinsing zone 6′ which, according to the illustration in
The clean-water rinsing systems 41 and 42 which are illustrated in
The transporting arrangement 11 in
In respect of the top clean-water rinsing system 41, which can be pivoted about the pivot axis 59, the presence of wash ware in the entry region to the clean-water rinsing zone 6 is sensed by the detector 63. The detector 63, which is connected to the machine controller 55, determines—in a manner analogous to the variant according to
The clean water which, according to
Upon detection of the wash ware in the exit region of the clean-water rinsing zone 6 by the detectors 62 and 61, the respective clean-water rinsing systems 41 and 42 are returned to their starting position, i.e. in the direction of the exit region, i.e. in the direction of the arrow 40 of the clean-water rinsing zone 6, and the clean-water pump is deactivated by the machine controller 55.
The solution which is proposed according to the invention, and has been described with reference to the two variants illustrated in
The invention being thus described, it will be obvious that the same may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the invention, and all such modifications as would be obvious to one skilled in the art are to be included within the scope of the following claims.
Number | Date | Country | Kind |
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DE 10 2005 004300 | Feb 2005 | DE | national |
This nonprovisional application is a continuation of International Application No. PCT/EP2006/000117, which was filed on Jan. 10, 2006, and which claims priority to German Patent Application No. DE 102005004300, which was filed in Germany on Feb. 1, 2005, and which are both herein incorporated by reference.
Number | Date | Country | |
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Parent | PCT/EP06/00117 | Jan 2006 | US |
Child | 11882467 | Aug 2007 | US |