EP0292773B1 - Clearing device for used dining trays - Google Patents

Description

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

Such a system is provided for clearing the different parts of a used food tray, for sorting the different parts, and for removing waste, the empty food trays and the individual crockery and cutlery parts then being fed to a dishwasher.

Such systems are used especially for use in self-service restaurants, company canteens and airlines, where the individual crockery and cutlery parts, paper napkins etc. are arranged on a tray.

From DE-C-2443651 a clearing device for used dinnerware of the type described above is known, the loaded used food trays being guided upwards and turned around around a turning drum with drivers and against the pressure of a rear guide. The trays are then transported on a tray conveyor, all other parts are fed to another conveyor belt via an inclined chute. In a similar system according to DE-C-3 413 480, a conveyor belt is provided on a turning drum, which after turning and separating the turned-over trays is simultaneously used to feed the other cutlery parts into the area of the dishwasher. In another sorting machine for separating cutlery, crockery parts and waste according to DE-A-2 547 474, cutlery, crockery parts and waste are tipped together into a shaft in a water bath. While the heavy metallic cutlery parts are to be transported away via a cross conveyor arranged at the bottom of the water bath, the lighter crockery parts with higher buoyancy are to be driven upwards by a water flow provided from below and carried away below the water level through baffles to another cross conveyor opposite the cutlery conveyor where they are loaded onto a dolly.

From DE-B-1956049 a device with a magnetic tape or drum system for turning the trays and a sorting grate is known, in which a device for rinsing and welding away the leaking food remnants is attached.

Furthermore, a device for automatically sorting out disposable dishes from reusable dishes is known. Here, both reusable crockery and disposable crockery are first freed of sticky food and liquid residues by means of a compressed air jet directed vertically onto the crockery, then the lighter disposable crockery is lifted off the conveyor belt by means of a compressed air jet directed towards the underside of the dishes and by another one acting from the side Compressed air jet blown away to the side at the same time.

Finally, a system is known in which cutlery and other smaller parts, which are loosely placed on a first conveyor belt, fall down in a gap between another conveyor belt, and the tray conveyed further by the second conveyor belt with dishes and the like arranged thereon on End is separated into a tray track and another track, the parts on the tray being led into a water bath. At the end of the water bath, cutlery and crockery are separated. Light waste is also blown away laterally at the beginning of the process by horizontal nozzles.A vibrating conveyor is provided for the joint transport of tableware and cutlery parts, at the end of which the cutlery parts fall through a grate with longitudinal slots, while the tableware parts continue to another conveyor to get promoted. Lateral water jets act on the vibration conveyor. Likewise, the trays which are guided parallel to this are washed through washing nozzles and then immediately stacked.

The invention is based on the problem of designing a clearing system according to the preamble of claim 1 in such a way that fully automatic separation and removal of essentially all parts located on used food trays and automatic and separate supply of empty trays, crockery parts and cutlery parts to a dishwasher is possible, and that these parts are pre-cleaned.

The problem is solved according to the invention by the features of the characterizing part of claim 1. Further embodiments of the invention are protected in the subclaims.

In addition to the provision of removal devices or disposal devices for light waste and food residues, in particular a crockery and cutlery conveyor in the form of a vibrating grate is provided, through the longitudinal slots of which only cutlery and waste parts can fall and can be directed into the gutter of a water trough, where they can be directed below the water surface and meet cutlery conveyor arranged along the water tub, which feeds the cutlery parts, preferably via a further rising conveyor, to a separate cutlery track in a dishwasher.

Above the vibrating grate, a conveyor belt with staggered, flexible and narrow alignment belts can be provided, which slide across the vibrating grate and align the cutlery and any remaining waste and the like in the direction of the longitudinal slots of the vibrating grate. Appropriately, about four successive rows of about five to six individual, a few centimeters wide alignment tapes are each slightly offset in the transverse direction, the offset starting again, so that, for example, the arrangement of the alignment tapes in every fifth row is the same.

The cutlery parts can be aligned with the longitudinal channel of the water trough by means of a slide that is inclined in the direction of conveyance and thus inclined to the side.

The vibrating device for the vibrating grate can be attached to the side by means of lateral fastening to the elastic bands, whereby the grating is occasionally triggered by a motor control and cams and automatically returns to the opposite position as a result of the stretchable elastic bands.

The tray conveyor can lead into an upper rinsing path, the vibrating grate arranged underneath a lower rinsing path for dishes, glasses, etc., while the cutlery conveyor, preferably via a lifting conveyor, can lead into a rinsing path on the side of the lower rinsing path mentioned within a conventional dishwasher.

A coordinated, sophisticated waste disposal system and pre-rinsing system can be provided, which on the one hand leads to the early removal of paper napkins and the like, and on the other hand effectively pre-cleans the essential parts, in particular the dishes, so that the actual rinsing process can be shortened and the cleaning effect can be significantly improved. In the entrance area of the used food trays, horizontal blow nozzles are provided for the lateral removal of paper, light waste, etc., which can fall into the water basin underneath and can be discharged via an inclined overflow. Subsequently, sharp water jets, diagonally from above, can remove a large part of the food residues from the trays, dishes, etc., which are also discharged laterally and from there into the water pan below. In this method, it has proven to be extremely advantageous to hold trays, cutlery items and in particular crockery items by means of special hold-down devices so that they are not blown away.

These hold-down devices can be relatively heavy rods which are arranged next to one another in the conveying direction and are mounted so as to be vertically movable. The entry section for the tray can be bevelled upwards. Several hold-down devices of this type can be arranged one behind the other. Additional pre-rinsing devices can be provided for the tray within the turning device. If cutlery and crockery items are transported on the vibrating rack, nozzles arranged from above and below can provide further cleaning. At the same time, any light waste etc. that may still be present can be discharged laterally.

This system therefore first includes the removal of light waste such as paper napkins, paper bags for sugar, salt, pepper and the like. Then the food remnants are also removed by the flushing nozzles, which are only possible in such an intensive form by using the holding-down devices described. This eliminates the annoying and unsanitary manual removal of these parts by operating personnel that was previously required. While comparable previous systems required around six to eight operators, this means that only one or two people are now required, who essentially carry out control and correction functions.

The preferably provided ingenious multi-stage pre-wash system, which happens during normal sorting and therefore without loss of time, furthermore reduces the performance requirements for the downstream dishwasher and still leads to clean and hygienic crockery and cutlery parts. The system already leads to a sorting of crockery and cutlery, which can also be kept in the dishwasher.

The tray, including dishes, is encompassed in a manner known per se by a turning drum which has a rear wall in the actual turning area. The leadership of the Trays are made by means of flexible carriers that are radially outward on the circumference. Cutlery and crockery often rest on a doily made of paper or similar material, which is used essentially as an ornament. It was found that this doily underneath was generally not removed by the device mentioned. An otherwise fully automatic system, that is to say practically no operating personnel, therefore requires its own operator only to remove this decorative doily. In order to avoid such an operator and manual intervention, an arc-shaped and fixed bracket is preferably arranged in the area of the mudguard of the turning drum, which extends from the inner circumference of the lower, input-side end of the turning drum to the area of the free ends of the flexible drivers, specifically in the Middle part of the turning drum and in the direction of movement of the trays. The paper doily falling down when it tilts then hooks onto this bracket and is touched by the tray, where it can be removed by the provided blow-off devices etc.

Sometimes, however, the doily smeared with food residues or possibly also soaked with moisture in the dishwasher sticks to the tray bottom and does not fall down. For this purpose, as a further embodiment of the invention, a first air nozzle is provided which is oriented upwards towards the tray bottom and which safely transports the doily downwards. So that the doily lying below can be safely removed in connection with the bracket just mentioned or also independently of it, a second horizontally acting air nozzle is preferably arranged, which blows away the doily falling down to the side. Both air nozzles are arranged one behind the other between the carriers and can be operated simultaneously by a single air supply.

Figur 1

eine schematische Gesamtanordnung einer Sortieranlage von der Seite,

Figur 2

einen Querschnitt durch die Darstellung von Figur 1 in Richtung C-D,

Figur 3

eine Draufsicht auf die Anlage unter spezieller Darstellung des Zufuhrförderers mit darauf angeordneten stangenförmigen Niederhaltern und daneben die Wasserwanne mit darin angeordnetem Besteckförderer sowie den quer hierzu angeordneten Wasserüberlauf für Leichtabfälle, Speisereste und dergleichen,

Figur 4

eine Draufsicht auf den (verbreiterten) Rüttelrost in Anpassung an die anschließende Spülmaschine, sowie dahinter schematisch die Wasserwanne.

An embodiment of the invention is shown in the drawing. It shows:

Figure 1

a schematic overall arrangement of a sorting system from the side,

Figure 2

2 shows a cross section through the representation of FIG. 1 in the direction of CD,

Figure 3

2 shows a plan view of the system with a special representation of the feed conveyor with rod-shaped hold-down devices arranged thereon and next to it the water tub with the cutlery conveyor arranged therein and the water overflow arranged transversely thereto for light waste, food waste and the like,

Figure 4

a plan view of the (widened) vibrating grate in adaptation to the subsequent dishwasher, and behind it schematically the water pan.

In the drawing, the same parts are provided with the same reference numerals. The function of the arrangement is to be explained below essentially using FIG. 1.

The used food trays are introduced into the clearing system via the feed conveyor (23) in the form of a conventional conveyor belt. Right at the beginning, a disposal device (36) for light waste is provided, which consists of horizontal air nozzles and lifts up and swirls this light waste laterally, after which it falls into the water basin (34) underneath. Then the food trays (21) with crockery parts (20), cutlery parts (32) (not shown) and food waste in the area of hold-downs (38) with rods (40) and rod bearings (39) to achieve vertical mobility of the same. A first pre-rinsing device in the form of slightly obliquely inclined, but essentially vertical nozzles (37) generates a sharp jet of water and in this way removes food residues and the like from the trays and the dishes located thereon, the food residues etc. whirled up and discharged laterally, where they also fall into the water tank (34) underneath. The trays pretreated in this way then get into the area of drivers (25) of a turning drum (24) which can be rotated in the direction of the arrow, where they are guided on lateral guide edges of the rear wall (4) of the turning drum (24) (not shown). However, these leading edges are designated (26). Further essentially horizontal flushing nozzles (55) are arranged in the region of the rear wall (4) in order to carry out additional cleaning. The trays leave the turning drum (24) as empty trays (29) in the turned state and are transported essentially horizontally by a first empty tray conveyor (27). In the illustration in FIG. 1, this is followed by a second empty tray conveyor (28), also in the form of a conveyor belt. The first conveyor belt (27) has the special feature that the first pair of bearings is inclined downwards from a spatial point of view, while the second pair of bearings (59), which can also be common to both conveyors (27) and (28), is arranged horizontally. The second empty tray conveyor (28) is guided to an upper tray rinsing track (51) of a dishwasher (12).

After turning over the food trays (21), the parts arranged thereon, essentially crockery parts (20) and cutlery parts (32), fall into the spaces between the finger-like drivers (25) of the rotating turning drum (24) and become one from below the tray conveyor (27) or (28) arranged slide (30) and from there to the vibrating grate (31). A vibrating device (50) is shown schematically in the central area on the vibrating grate (31). On the side wall (61) of the vibrating grate (31), the ends of the crossbars (60) are drawn, on which the (not visible) bars (65) arranged parallel to the side wall (61) are held, between which the (not visible) Extend the longitudinal slots (41). Crockery (20) (not visible) cutlery (32) lies on the vibrating grate (31) with the opening facing downwards, falling through longitudinal slots on its way to the lower end of the vibrating grate and hitting a laterally beveled slide (14) , of the they fall into a longitudinal channel (48) of the water tub (34) and hit a cutlery conveyor belt (42) arranged below the water surface. With (44) the water level of the water pan (34) is designated. The cutlery conveyor consists of a first horizontal underwater conveyor (42) and a second lifting conveyor (53) rising to the front. Carriers (43, 17) convey the cutlery parts in the direction of the arrow, where they strike the dishwasher conveyor track (22) at the upper end of the second cutlery conveyor (17), where they are fed to the dishwasher (12) in the direction of the arrow. The cutlery track (22) is arranged next to the wider tableware conveyor track (52).

Underwater cutlery flushing nozzles (66) and (67) are arranged in the end area of the horizontal cutlery conveyor (42) and in the beginning area of the lifting cutlery conveyor (53).

Underneath the feed conveyor (23) there is also another chute (47) inclined for conveying, onto which the light waste such as paper that is blown away laterally by the blowing nozzles (36) impinges and is guided into the trough of the water trough (34) underneath , where they usually swim and are led away to the side by a water overflow (49) (not visible in FIG. 1).

Lower rinsing nozzles (54) and upper rinsing nozzles (57) are provided to the side of the vibrating grate (31), which additionally pre-rinse crockery and cutlery items before they fall through the grating.

Above the vibrating grate (31) is a conveyor belt (45) which is moved in the transport direction and has flexible and narrow alignment belts (46) which are offset, the direction of movement relating to the underside of the conveyor belt (45).

The end of the clearing system and the transfer area into the dishwasher (12) is otherwise indicated by a boundary line.

The reversible drum (24), which is known per se, shows flexible drivers (25) directed radially outwards and a rear wall (4) in the rear actual reversing region. Along the turning drum, an arc-shaped fixed bracket (70) is provided, which begins on the hold-down device (40) in front of the actual area of the turning drum, rests on the lower end of the turning drum and from then on is curved outwards to the free end of the drivers (25). extends in the exit area of the turning drum. This bracket (70) is used to hold doilies falling down, on which the cutlery and dishes are often placed. In the exit area of the turning drum, a (second) horizontally oriented air nozzle (72) can be seen in the area between the drivers (25). A first air nozzle directed vertically upward can be seen in FIG. 2 and FIG.

FIG. 2 shows a section CD of the clearing system according to FIG. 1 in a schematic illustration. At the very top, the tray conveyor (28) is shown in the form of two belt belts arranged opposite one another and running on (not shown) rollers, on which the inverted empty tray (29) rests. Below this is shown the alignment conveyor belt (45) with flexible alignment belts (46) arranged thereon, which almost touches the strips (65) of the vibrating grate (31). A slide (14) inclined to the side for cutlery items is arranged underneath. Below this, the feed conveyor (23) for the used food trays (21) is shown, the tray and cutlery and in particular crockery parts being held down by rod-like hold-down devices (40), so that these parts are not in the form of essentially vertical blow nozzles due to the pre-rinsing device (37) or usually water rinsing nozzles are washed away. A further slide (47) is provided below and offset from the slide (14) previously described, which slide dropping parts further into the longitudinal channel (48) of the water pan (34).

Beneath this slide (47) there is a further slide (62) which also introduces the parts swirled up or to the side by the pre-rinsing device (37) into the longitudinal channel (48). A further oblique baffle plate (63) is aligned opposite the longitudinal channel (48). The heavy cutlery parts remain in the longitudinal channel (48) on the cutlery conveyor (42) and are transported on. In contrast, light waste (35) such as paper etc. floats on the water surface of the longitudinal channel (48) and is conducted via a water overflow (49) arranged perpendicular to the longitudinal channel (48) into a lower basin (64) and discharged there or after filtering the water pan again fed.

The upper section schematically shows the two upper and the two returning lower ropes or the like of the tray conveyor (28) along with lateral protective edges on which the turned-over empty trays (29) rest and in the direction of the upper dishwasher belt (51) (see figure 1) be promoted. In the central region of the tray conveyor (28), the upper end of the arcuate catch bracket (70) for paper or similar doilies falling from the empty tray can be seen. To the right of this is an upward-pointing nozzle, preferably an air nozzle (73), whose jet is directed at the bottom of the turned-over empty tray (29). Again to the right and outside of the transport area, a second horizontally oriented nozzle, preferably an air nozzle (72), can be seen, the jet of which is directed into the area below the inverted empty tablet (29) in order to detect downward ones including those on the bracket (70) Guide paper or similar doilies to the side where they can fall into the water tank (34) underneath. Both nozzles (72, 73) can be supplied and operated simultaneously via a single fluid line, preferably in the form of a compressed air line (71).

FIG. 3 shows the top view of the water trough or the longitudinal channel (48) with the first horizontal cutlery conveyor (42) and the second cutlery conveyor (53) rising to the dishwasher (12), as well as the water overflow (49) and the drainage water basin (64) for Light waste, food residues etc. In front of it is shown the feed conveyor (23) with used food trays (21) thereon and rods (40) of the hold-down device (38) arranged above it. In addition, downward-directed flushing nozzles (37) are shown, which are arranged on corresponding two cross members.

FIG. 4 shows a plan view of the vibrating grate (31), which is widened in relation to the slide (30) which adjoins the turning drum (24) in order to adapt to the dimensions of the dishwasher (12). The cutlery flushing track (22) is shown on the rear side. Otherwise, the same parts are provided with the same reference numerals and, inter alia, the side walls (61), the longitudinal slots (41) and the grate strips (65) forming the slots can be seen. Likewise, flushing nozzles (54) and (55) can be seen according to the side view of FIG. 1.

Above and in the middle region of the turning drum (24), the upper end of an arch-shaped bracket (70) for receiving doilies made of paper or the like can be seen, which fall down from the turned over empty tray. In order to support this drop or to make it possible in the first place, a fluid line, preferably a compressed air line (71) is provided, which pressurized fluid, preferably compressed air, into a first nozzle (72) directed horizontally onto the area below the (not shown) empty trays and one guides the second nozzle (73), the latter being oriented substantially vertically or obliquely upwards, namely towards the bottom of the inverted trays.

Claims (12)

1. A clearing system for used dinner trays (21) to be fed to a dishwasher (12), said system comprising

   a) a feeding conveyor (23) for the used dinner trays (21),

   b) a turning device, preferably a rotatably driven turning drum (24) having circumferentially disposed drivers (25) and a guide means (26) for the dinner trays (21),

   c) a tray conveyor (27, 28) for the turned empty trays (29),

   d) a dish and cutlery conveyor (30, 31) inclined in the conveying direction for the dishes (20), pieces of cutlery (32), pieces of waste (33) and food scraps (56) falling from the turned dinner trays (29), parts including pieces of waste dropping through said conveyor,
   characterized by

   e) a water tub (34) disposed at the bottom for receiving and discharging light-weight waste (35),

   f) removing and discharging means (36) for light-weight waste such as paper (35) and food scraps (56),

   g) pre-rinsing means (37; 38-40; 66, 67; 54, 55; 57) for dishes (20) and pieces of cutlery (32),

   h) a dish and cutlery conveyor configured as a rocking grate (31) and provided with longitudinal slots (41) of such a kind that, with the exception of possible residual pieces of waste, only pieces of cutlery (32) will drop therethrough,

   i) a cutlery conveyor (42) having drivers (43) within the water tub (34) and below the water level (44), the pieces of cutlery (32) striking said conveyor and being transported towards the dishwasher (12).
2. System according to claim 1, characterized by a conveyor belt (45) which is arranged above the rocking grate (31) and moves in the direction of transport and which is provided with offset pliable and narrow alignment bands (46) sweeping across the rocking grate (31) to align pieces of cutlery (32) and, optionally, remaining pieces of waste and the like in the direction of the longitudinal slots (41) of the rocking grate (31).
3. System according to claim 1 or claim 2, characterized by a slide (14, 47) inclined relative to the conveying direction onto which pieces of cutlery (32), pieces of waste and the like will drop and be guided to a longitudinal trough (48) in the water tub (34) in which the cutlery conveyor (42) is disposed, wherein light-weight waste (35) and pieces of scrap are discharged via a water spillway (49) and an installed water flow across the conveying direction of the cutlery conveyor (42).
4. System according to any one of the claims 1 to 3, characterized by a rocking mechanism (50) for the rocking grate (31) which is mounted for lateral movement on elastic side bands and is intermittently started on said side by a motor control means and cams or the like.
5. System according to any one of the claims 1 to 4, characterized in that the tray conveyor (28) is guided into an upper washing track (51) for empty trays (29), the rocking grate (31) disposed therebeneath including the dishes (20), glasses and the like is guided into a lower washing track (52), and that the cutlery conveyor (42) is guided, preferentially through a lifting conveyor (53), into a lateral washing track (22) of an integral dishwasher (12).
6. System according to any one of the claims 1 to 5, characterized by a removing device (36) for light-weight waste (35) configured as horizontal blow nozzles mounted above the used dinner trays (21) being fed, wherein paper and the like is whirled upwards and sideways and drops into the water tub (34) disposed below.
7. System according to any one of the claims 1 to 6, characterized by a first pre-rinsing device (37) for light-weight waste and food scraps configured as vertical or inclined high-intensity flushing nozzles directed from above onto the used dinner trays (21) being fed to provide for upward and sideways whirling of paper, other light-weight waste (35), food scraps (56) and the like which will subsequently drop into the water tub (34) disposed below,
   wherein trays (21, 29), dishes (20) and pieces of cutlery (32) are retained by upwardly compliant hold-down means (38), preferentially by a plurality of relatively heavy bars (40) which are arranged in side-by-side relationship and aligned in the conveying direction and which are supported for upward displacement, wherein the bars are bevelled at the entry-side end of the dinner trays (21) and a plurality of such hold-down means (38) may be arranged in series.
8. System according to any one of the claims 1 to 7, characterized by a second pre-rinsing device configured as nozzles (54, 57) which are mounted beneath and above the rocking grate (31) for pre-cleaning through the longitudinal slots (41) of the rocking grate the dishes (20), pieces of cutlery (32) and the like which are placed upside down on the rocking grate (31).
9. System according to any one of the claims 1 to 8, characterized by a third pre-rinsing device configured as substantially horizontal and axially parallel nozzles (55) inside the turning drum (24) and in the vicinity of the drivers (25).
10. System according to any one of the claims 1 to 9, characterized by underwater-type cutlery washing nozzles (66) at the end section of the horizontal cutlery conveyor (42) and by second cutlery washing nozzles (67) at the starting section of the lifting conveyor (53) for cutlery, the washing nozzles being oriented towards the cutlery area of the conveyors.
11. System according to any one of the claims 1 to 10, characterized by an arc-shaped and stationary rail (70) which is mounted in the vicinity of the rear wall (4) for the turning drum (24) and extends outwardly in the direction of movement from the inner periphery of the turning drum (24) towards the area of the free ends of the drivers (25) in the exit area of the turning drum (24).
12. System according to any one of the claims 1 to 11, characterized by a vertically upwardly oriented fluid nozzle, preferably an air nozzle (73), and downstream thereof a horizontally oriented second fluid nozzle, preferably an air nozzle (72), and preferably with a common fluid supply means (71) in the exit area of the turning drum (24) intermediate the drivers (25).

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