WO2019180256A1

WO2019180256A1 - Ware handling apparatus

Info

Publication number: WO2019180256A1
Application number: PCT/EP2019/057337
Authority: WO
Inventors: Christopher James ROSSER; Henry Matthew Lawrence FLETCHER
Original assignee: Elior Group
Priority date: 2018-03-22
Filing date: 2019-03-22
Publication date: 2019-09-26
Also published as: GB2572197A; GB201804635D0

Abstract

A handling tool for handling wares in a warewasher system is disclosed. The handling tool comprises means for engaging with and releasably securing to a ware, for transporting the ware from a first location to a second location in a warewasher system. A compliant, resilient ware engaging plate is provided that has a generally planar region when not engaged with a ware. In operation, the ware engaging surface of the ware engaging plate will conform to a surface of a ware to be handled. The handling tool is coupled to a vacuum source for applying at least a partial vacuum between the ware engaging surface and the ware to be handled.

Description

Ware Handling Apparatus

The present invention relates to an apparatus for handling wares for a warewashing system and has particular, although not exclusive, relevance for use as a tool for releasably attaching to objects, such as crockery or glassware, for transport from one location to another.

In large kitchens such as those found in hotels or hospitals there is a need to rapidly clean very large quantities of dining ware. In these high-volume environments, it is prohibitively time consuming to wash the objects by hand, and so the process is typically automated using a warewasher system.

Warewasher systems process large numbers of objects, such as crockery or glassware, to clean the objects of debris such as food waste. In order to increase the efficiency of the cleaning process, the objects that enter the machine are often separated into different types. For example, crockery and glassware may be separated from dining trays and other objects. In low-capacity warewasher systems, objects may be manually separated by the user when placing the objects into the machine. High capacity warewasher systems on the other hand are highly complex machines able to process hundreds to thousands of objects per hour, and may mechanically separate the objects automatically before the cleaning process begins.

When the separation process is performed automatically by the warewasher, there is a need to selectively transport crockery, such as plates and bowls, from one area of the warewasher to another relatively swiftly. However, the surface of crockery that enters a warewasher is typically contaminated by a range of different types of debris, such as food waste, liquids, cutlery, napkins, yoghurt pots, drinks cans, receipts or other inorganic waste, which makes automatic handling of the crockery challenging. This challenge is made more complex by the need for the warewasher system to be compact, and to be able to process large numbers of objects as rapidly and reliably as possible.

Currently, there are a number of grippers available that are able to releasably attach to crockery in a warewasher for the purposes of such transport. However, these grippers are often unable to reliably transport crockery that is contaminated by large amounts of food waste, or that is partially obstructed by items such as cutlery. This can result in an increased risk of crockery becoming detached from a gripper, which may result in damage to the crockery or machinery, and possibly require interruption of the cleaning process to retrieve items that have been dropped. It can be seen that this may reduce the throughput of the system undesirably.

The currently available grippers typically make use of precise positional alignment with respect to the crockery that is being transported for a secure attachment to be made. However, these systems are often unable to process crockery at the high volumes required in a warewasher system. These grippers may also require an impractical amount of space in which to operate and are often prohibitively expensive.

The present invention seeks to provide an apparatus for releasably attaching to objects for use in a warewashing system, and associated apparatus and methods, for meeting or at least partially contributing to the above need.

In one aspect the invention provides a handling tool for handling wares in a warewasher system, the handling tool comprising: means for engaging with a ware to be handled for releasably securing the handling tool to the ware for transport of the ware from a first location to a second location in the warewasher system; wherein the engaging means comprises: a resilient ware engaging plate having a ware engaging surface for mutually engaging with a surface of the ware to be handled; and means for coupling the handling tool to a vacuum source for application of at least a partial vacuum between the ware engaging surface and the surface of the ware to be handled for releasably securing the ware to the handling tool during operation; and wherein the ware engaging plate has a generally planar shape; and wherein the ware engaging plate is formed of compliant resilient material whereby, in operation, the ware engaging surface will conform to a surface of the ware to be handled.

The ware engaging surface may be generally planar over a greater part of the ware engaging surface when not engaged with a ware to be handled.

The ware engaging surface may be smooth.

The ware engaging plate may comprise an aperture via which said at least a partial vacuum can be applied. The means for coupling may comprise a conduit for forming a fluid path from the aperture to the vacuum source. The ware engaging surface may have a surface area that is greater than a transverse cross-sectional area of the aperture. The ware engaging surface may have a surface area that is at least five times the transverse cross-sectional area of the aperture. The ware engaging surface may have a surface area that is at least ten times the transverse cross-sectional area. The aperture may be located generally centrally to, and through the plane of, the ware engaging plate. The aperture may have at least one of the following geometries: circular with a diameter ~25mm to ~40mm, for example ~30mm (with tolerances of plus or minus 20%); and a transverse cross-sectional area of ~500mm² to -1250mm², for example ~700mm² (with tolerances of plus or minus 40%).

The ware engaging plate may comprise a concave portion extending from the aperture to the ware engaging surface.

The height of the concave portion along an axis generally orthogonal to a plane of the ware engaging surface, from the ware engaging surface to the aperture, may be between 5mm and 20mm, (e.g. 10mm).

The largest width of the concave portion, along an axis generally parallel to the plane of the ware engaging surface (e.g. the diameter of a concave portion, having a circular cross-section, at its widest part) , may be between 120mm and 200mm.

The fluid conduit may be provided with a filter for inhibiting material from being drawn through the conduit towards the vacuum source. The filter may be formed of a metallic material.

The ware engaging plate may have a geometry (e.g. thickness and transverse cross- sectional area) whereby the ware engaging plate is sufficiently rigid to maintain the generally planar shape when not engaged with a ware, and sufficiently compliant to conform to a surface of the ware to be handled during operation to releasably secure the ware to the handling tool. The ware engaging plate may, for example, have a thickness in the range ~1 mm to ~3mm, for example ~2mm (with tolerances of plus or minus -20%). The ware engaging plate may, for example, have at least one of the following geometries: circular with a diameter of ~200mm to ~350mm, for example ~275mm (with tolerances of plus or minus 20%); and a transverse cross-sectional area of -30000mm² to -100000mm², for example -60000mm² (with tolerances of plus or minus 40%). The ware engaging plate may, for example, have a transverse cross-sectional area that is configured to be similar to (e.g. within 20% of) an area of a surface, of a largest ware that the handling tool is configured to handle, which surface the ware engaging surface will engage with in operation. The ware engaging plate may be generally disc shaped. The ware engaging plate may be formed of a material from the list: food safe polyurethane; rubber; and silicone. The engaging means may further comprise at least one supporting element extending from a generally central region on the ware engaging plate, whereby to provide additional rigidity across that central region. The supporting element and the ware engaging plate may be formed of the same compliant resilient material. The supporting element may be one of: frustoconical in shape; disc shaped; and hemispherical in shape. The supporting element may have at least one of the following geometries at an interface with the ware engaging plate: circular with a diameter of ~100mm (with tolerances of plus or minus 20%); and a transverse cross- sectional area of -7850mm² (with tolerances of plus or minus 40%). The supporting element may have a transverse cross-sectional area that is configured to be smaller than an area of a part of a smallest ware that the handling tool is configured to handle, which part the ware engaging surface will engage with in operation.

The handling tool may further comprise a resilient mechanism configured to allow, in operation, reciprocal movement of the ware engaging plate along an axis generally orthogonal to a plane of the ware engaging plate whereby, in operation, the relative height of the ware engaging plate will adjust automatically to ware-to-ware variation in a maximum height of wares to be handled. The resilient mechanism may be further configured to allow, in operation, rotational movement of the ware engaging plate about an axis generally parallel to the plane of the ware engaging plate whereby, in operation, an angle of the ware engaging surface will adjust automatically to ware-to- ware variation in an angle of a surface of the wares to be handled.

The resilient mechanism may be configured to tolerate reciprocal movement of up to 30mm (e.g. 12mm) along the axis generally orthogonal to a plane of the ware engaging plate.

The handling tool may comprise a sensor for sensing if the handling tool is engaged with the surface of a ware.

The handling tool may comprise a sensor for sensing the weight of an object that the handling tool is attached to.

In one aspect the invention provides apparatus for handling wares in a warewasher system, the apparatus comprising: means for identifying a ware to be transported from a first location to a second location in the warewasher system and for determining a position of the identified ware; means for transporting the identified ware from the first location to the second location using a handling tool as set out above; and a pump for providing said vacuum source for said handling tool. In one aspect the invention provides a method of handling wares in a warewasher system, the method comprising: identifying a ware to be transported from a first location to a second location in the warewasher system and determining a position of the identified ware; and transporting the identified ware from the first location to the second location using a handling tool according to an above aspect.

Each feature disclosed in this specification (which term includes the claims) and/or shown in the drawings may be incorporated in the invention independently (or in combination with) any other disclosed and/or illustrated features. In particular but without limitation the features of any of the claims dependent from a particular independent claim may be introduced into that independent claim in any combination or individually.

Embodiments of the invention will now be described by way of example only with reference to the attached figures in which:

Figure 1 a shows a simplified schematic diagram of an area of a warewasher system;

Figure 1 b shows a simplified schematic diagram of an apparatus for separating wares in a warewasher system;

Figure 2 shows a 3D view of a handling tool;

Figure 3 schematically illustrates a cross section of the handling tool of Figure 2;

Figure 4 schematically illustrates the handling tool of Figure 2 attached to an item of crockery;

Figure 5 shows a top-down view and a 3D view of a variation of the handling tool; and

Figure 6 shows a cross section of another variation of the handling tool.

Overview

Figure 1 a shows, for illustrative purposes, a simplified schematic diagram of an area of a warewasher system generally at 1. The system comprises a ware separation area comprising a first conveyor 3 for transporting, in the direction indicated by arrow A, items (‘wares’) through an automated ware separation apparatus 5 and a warewasher transport area comprising a second conveyor 7 for transporting, in the direction indicated by arrow B, items into a warewasher 9. Figure 1 b shows the ware separation apparatus 5 in more detail. As seen in Figure 1 b, the ware separation apparatus 5 comprises a vision system 51 for identifying and locating wares for separation, a handling system 53 for picking up, handling, and transporting items to the warewasher transport area, and a control unit 55 for controlling the vision system 51 and the handling system 53.

The vision system 51 , in this example, comprises a digital camera positioned over conveyer 3 for capturing images of items passing through the automated ware separation apparatus 5.

The handling system 53, in this example, comprises a moveable arm 57 coupled to a handling tool 10 for picking up and holding items during transport, by the arm 57 to the warewasher transport area. The handling tool 10 is configured for securing the items to be transported using suction provided by a high-power vacuum pump 59.

The control unit 55 receives images from a vision system 51 and, based on the received images, controls the moveable arm 57 and the vacuum pump 59 to pick up items from the first conveyor 3, using the handling tool 10, and to transport the item to the second conveyor 7.

As seen in Figure 1 b, in this example, the items (wares) transported by the first conveyor 3 include crockery 43 and glassware 44 arranged on a tray 46. The items may be contaminated by debris such as food waste 42 and liquids 45. The skilled person will appreciate that other items may be present on the conveyor 3 or tray 46, such as napkins or cutlery.

As described in more detail later, the handling tool 10 has a particularly beneficial configuration comprising a resilient, plate-like, skirt supported by at least one structural element. The skirt comprises an opening to a suction path, through which air may be drawn by the pump 59, to form a partial vacuum between the skirt and an item that is to be transported. This allows the apparatus to be securely and releasably attached to the item, so that the item can be rapidly moved to another location.

The resilient skirt (or‘plate’) is formed of a relatively soft and compliant material that is able to deform around debris present on the surface of the item, thus enabling a seal or partial seal to form between the skirt and the item. Because of the geometry and flexibility of the skirt, the partial vacuum can be formed even when the surface of the item is contaminated by relatively large objects such as cutlery, food waste, or when the surface of the item has significant curvature, for example if the item is a bowl. Beneficially, the use of the resilient skirt and the relative geometry of the handling tool, and in particular the suction path, also greatly reduces the amount of air and debris that flows into the apparatus during operation. The configuration of the handling tool and in particular the flexibility of the skirt also allows the apparatus to reliably attach to objects even when there are large positional errors or variations in the orientation of the objects.

Whilst the skirt is locally flexible so that it may deform around debris or irregular shapes, the skirt remains globally rigid such that the overall structure of the skirt is maintained even when the partial vacuum has formed, allowing undesirable folding of the skirt to be prevented.

It can be seen, therefore, that because of its design, the handling tool 10 for picking up and holding items, identified based on feedback from the vision system 51 , during transport is particularly position tolerant. More specifically, the handling tool 10 will successfully engage with, secure, and hold onto wares even when the tool is not precisely centred. For example, the handling tool 10 can successfully pick up a ware such as a plate or bowl even when the centre of the tool 10 engages with a location away from the centre (e.g. radially towards the edge of the ware). The handling tool 10 even has the potential to successfully pick up items when it engages with a non- flat or non-horizontal surface of the ware (e.g. the sloping side of a bowl or a raised edge of a plate or saucer).

Moreover, because the handling tool 10 is particularly tolerant to a lack of precision in a location determined, for an identified ware, by the control unit 55 the use of the position tolerant handling tool 10 can significantly reduce the precision constraints that have to be imposed on the positioning algorithms used by the control unit 55. This in turn means that the control unit 55 has the potential to accurately identify wares and determine sufficiently precise position information relatively quickly thereby increasing the possible throughput achievable using the ware separation apparatus 5. Alternatively, or additionally, the reduction in the position constraints allows more processing time to be devoted to accurately identifying wares and classifying them (e.g. as plates, bowls, ups, glasses, etc.) thereby providing the potential to improve separation reliability without a commensurate reduction in throughput. In summary, therefore, the handling tool 10 can be used as an end-effector that allows a robot to pick up a piece of standard crockery. It is designed to be compliant to large positional errors (typically, but not limited to, >1 mm, up to 10-20mm) and to handle crockery that is covered by a wide range of food waste, liquid, debris, cutlery and other items that can be expected on a piece of crockery. The handling tool 10 can then move the entire item to another location at a rapid pace. The use of a large high powered vacuum system helps to ensure sufficient suction to lift the item even with leakage in the system.

Soft compliant material towards the periphery of the skirt conforms, in operation, to the shape of the ware underneath, including cutlery or debris. This helps to ensure that a sufficient vacuum seal generally occurs at some point in the entire (relatively large) area. This also ensures that any air path under the skirt is relatively convoluted, leading to greatly reduced air flow into the system towards the pump thereby reducing the risk of blocking and ingestion of large quantities of waste into the vacuum system.

Illustrative Examples

The handling tool 10 will now be described in more detail, by way of example only, with reference to Figures 2 to 4.

Referring to Figure 2, this shows a simplified 3D view of the handling tool 10. The tool 10 comprises a resilient skirt 14, a supporting part 13 and a conduit 12.

The supporting part 13 is attached to, and coaxially aligned with, the resilient skirt 14 and provides structural support for the resilient skirt 14. The conduit 12 is coaxially aligned with, and passes through the supporting part 13 to the resilient skirt 14 as indicated by the dashed lines. In the present example, the supporting part 13 is illustrated as having a frustoconical configuration, although the skilled person will appreciate that any other suitable shape such as a hemispherical or cylindrical configuration may be used. In the present example, the resilient skirt 14 is illustrated as being a generally flat circular (or‘disciform’) shape, although the skilled person will appreciate that any other suitable non-circular plate-like shape such as an elliptical or polygonal plate may be used (e.g. to provide better performance with particular types or shapes of crockery).

The resilient skirt may beneficially be formed of any suitable resilient material such as food-safe polyurethane. However, it will be appreciated that any other suitable material such as silicone may be used. The supporting part 13 and the conduit 12 may be formed of any suitable material, for example a material such as food-safe polyurethane, rubber or silicone may be used.

The diameter of the skirt 14 is beneficially between 200mm and 350mm. However, a particularly advantageous diameter of the skirt 14 is 275mm, which provides a suitable area of the lower surface 14-1 of the skirt to engage with a typical item of crockery 43 found in a warewasher system.

The thickness of the skirt 14 is beneficially between 1 mm and 3mm, such that the flexibility of the skirt 14 is suitable for deforming around debris found on the surface of an item of crockery, whilst maintaining the shape of the skirt 14 when not engaged with an item of crockery. However, a thickness of the skirt 14 of 2mm was found to be particularly beneficial for maintaining global rigidity whilst allowing localised flexibility.

The internal diameter of the conduit 12 is beneficially between 25mm and 40mm. However, a particularly advantageous diameter was found to be 30mm, to provide sufficient fluid flow through the conduit 12 and to inhibit the formation of obstructions inside the conduit 12 by debris.

The supporting part 13 beneficially has a diameter of 100mm. However, it will be appreciated that the diameter of the supporting part 13 may be larger or smaller depending on the size of the item that is to be picked up.

Figure 3 schematically illustrates a cross section of the handling tool 10. The resilient skirt 14 comprises an opening that is aligned with the opening at the lower end of the conduit 12, so that a path for fluid flow 11 indicated by the dashed line is formed. When the pump 59 is connected to the upper end of the conduit and turned on it thus attempts to draw fluid (air) through the opening of the resilient skirt 14 and into the conduit 12 thereby providing suction. A filter 15 is provided in the conduit, proximate the opening in the skirt, to inhibit debris from entering the conduit 12 and forming an obstruction to fluid flow or damaging the pump 59. In the present example the filter 15 is shown positioned inside the lower end of the conduit 12 (e.g. for ease of access and cleaning). However, the skilled person will appreciate that the filter 15 may be located at any other suitable position inside the conduit 12, or may instead by provided separately by the pump. The pore size of the filter 15 is beneficially configured to inhibit the debris most likely to form an obstruction in the conduit 12 from passing through the conduit 12. For example, the width of the pores of the filter 15 may be smaller than the width of a typical grain of cooked rice. Beneficially, the filter may be formed of a relatively stiff, metallic material such as stainless steel, to provide increased resistance to deformation under pressure. However, it will be appreciated that any other suitable material may be used. Whilst beneficial, the filter 15 need not necessarily be provided. For example, if the handling tool 10 is used to transport clean, dry crockery at a later stage of the warewashing process then the filter may not be necessary.

The resilient skirt 14 has a first, generally planar but resilient, ware engaging surface 14-1 (on the underside of the skirt as viewed in Figure 3) for engaging with and conforming to a surface of a ware (such as a plate, bowl, or other item of crockery) during operation to form a sufficiently strong vacuum interface with the ware, to secure the handling tool 10 to the ware for reliable lifting and transporting of the ware to another location. The resilient skirt 14 has a second generally flat surface 14-2 (on the upper side of the skirt as viewed in Figure 3) that interfaces with the supporting part 13.

The supporting part 13 has a transverse cross-sectional area (perpendicular to a main central longitudinal axis through the conduit 12), where the supporting part 13 interfaces with the second surface 14-2 of the skirt 14, that is relatively smaller than the transverse cross-sectional area of the skirt 14 (in the plane of the skirt). Thus, the skirt 14 has a portion 14-3 (that is annular in the illustrated example) that extends outwardly, in a radial direction, beyond the interface 14-2 with the supporting part 13. This extended portion 14-3 of the skirt is thus more flexible than the portion that interfaces with the supporting part 13, allowing it to conform closely to the contours of a ware when, in operation, it is brought into contact with the ware and a vacuum is applied. The extended portion 14-3 is, nevertheless, rigid enough (by virtue of its thickness) to maintain its generally flat and planar shape when not engaged with a ware.

It will be appreciated that whilst the skirt 14 and supporting part 13 are described separately they may be formed as a single integrated part (e.g. using an appropriate moulding process or the like).

Figure 4 schematically illustrates the handling tool 10, in operation, attached to an item of crockery 43.

In operation, to arrive at the illustrated positon, it will be appreciated that the control unit 55 controls the moveable arm 57 to move the handling tool 10 into position such that the resilient skirt 14 engages with an identified item of crockery 43. The control unit 55 also controls the pump 59 to draw air through the conduit 12 to form suction. As can be seen in Figure 4, the resilient skirt 14 is in contact with an item of crockery 43 contaminated by food debris 42 and an item of cutlery 41. The resilient skirt 14 deforms to form a seal or partial seal with the crockery 43, despite the irregular surface presented by the food debris 42 and the item of cutlery 41. When the high- power vacuum pump 59 pumps air out of the conduit 12 a partial vacuum is formed in the area between the resilient skirt 14 and the crockery 43, and the handling tool 10 becomes secured to the crockery 43. The control unit 55 then controls the moveable arm 57 to transport the crockery 43 to another location. For example, the control unit may control the moveable arm 57 to transport the crockery 43 from the first conveyor 3 to the second conveyor 7.

After the crockery 43 has been transported to the desired location using the moveable arm 57, the partial vacuum is destroyed by allowing air to flow into the area between the resilient skirt 14 and the crockery 43, and the crockery 43 becomes detached from the resilient skirt 14. For example, air may be allowed to flow into the conduit 12 via a valve provided in the wall of the conduit. The valve may be controlled by the control unit 55. However, the skilled person will appreciate that air may be introduced into the area between the resilient skirt 14 and the crockery 43 by any other suitable method, to destroy the partial vacuum formed in the area between the resilient skirt 14 and the crockery 43.

Modifications and alternatives

An exemplary warewasher system and handling tool have been described above in detail. As those skilled in the art will appreciate, a number of modifications and alternatives can be made to the above examples and variations whilst still benefiting from the inventions embodied therein.

Figure 5, for example, shows top-down and simplified 3D views of a handling tool 10 in which struts 16 are beneficially provided on the upper surface of the resilient skirt 14. The struts 16 provide additional structural support for the resilient skirt 14 and help prevent undesirable folding of the resilient skirt 14. Although in the example shown in Figure 5 radial struts are provided, the skilled person will appreciate that any other suitable configuration may be used to provide structural support for the resilient skirt 14. For example, concentric rings around the central axis of the handling tool 10 may be provided on the upper surface of the resilient skirt 14. In Figure 6 an alternative configuration of the resilient skirt 14 and support 13 is shown in which the resilient skirt comprises a main, outer annular section 142 that is substantially perpendicular to a main central axis of the handling tool 10, and an inner concave section 141. Both sections 141 , 142 are coaxially aligned around the central axis of the fluid conduit 12 with the opening to the conduit in the skirt being located in the concave section 141. The concave section 141 is configured to form, when the handling tool 10 engages with a ware, a cavity centred on the opening to the fluid conduit 12, between the surface of the ware and an external surface of the concave section 141 of the skirt. Beneficially, the height of the cavity in the longitudinal direction, from a plane defined by the lower surface of the outer annular section 142, to the distal end of the conduit 12, may be between 5mm and 20mm, for example the height may be 10mm. The largest diameter of the cavity, in the transverse direction, is beneficially between 120mm and 200mm, depending on the dimensions of the ware that is being transported and the dimensions of the outer annular section 142. The formation of this cavity beneficially helps to reduce the amount of bridging and associated blockage that occurs across the opening in the skirt by relatively small particles of debris such as rice. The formation of the cavity was also found to beneficially improve the reliability of the attachment of the handling tool 10 to wares contaminated by significant amounts of debris such as food waste.

Beneficially, a resilient mechanism (such as, but not limited to, a damped spring) may be provided to provide tolerance for positional errors in the direction along the central axis of the tool. The resilient mechanism may be provided, for example, at an interface between the moveable arm 57 and the handling tool 10 or may be provided at any other suitable position (e.g. as a resilient portion of the conduit). For example, in operation, the moveable arm 57 may move the handling tool to a fixed height, and the provision of the resilient mechanism allows the height of the ware engaging surface 14-1 of the handling tool 10 to adjust to the height of the surface of the ware that is to be picked up. This beneficially reduces the precision required in the movement of the moveable arm 57 along the central axis of the tool 10. Additionally, the provision of the resilient mechanism (especially in combination with the flexibility of the resilient skirt 14) beneficially allows the handling tool 10 to attach to wares that are tilted such that, before the tool 10 is engaged with the ware, the surface of the ware with which the tool is to be engaged is at significant angle to the ware engaging surface 14-1 of the tool 10. Beneficially, the resilient mechanism may tolerate positional errors of up to 30mm in the direction along the central axis of the tool, for example a displacement of 12mm may be tolerated. The handling system 5 may be provided with a sensor for sensing if the handling tool 10 is engaged with the surface of a ware. For example, the handling system 5 may be provided with a sensor for sensing a displacement of the resilient mechanism, from an equilibrium position of the resilient mechanism when the handling tool 10 is not engaged with a ware. The sensor may be provided, for example, in the form of a linear encoder, a microswitch, a strain gauge or a flag breaking an optical beam. The sensor may be provided, for example, by the resilient mechanism. The provision of the sensor beneficially enables the handling system 5 to determine if an attempted engagement of the handling tool 10 with a ware is successful. Alternatively, the sensor for sensing if the handling tool 10 is engaged with the surface of a ware may be provided as a pressure sensor or an air flow sensor. For example, a change in the air pressure inside the conduit 1 1 , or a change in the flow rate of fluid through the conduit 1 1 , may be used to determine if the handling tool 10 is engaged with the surface of a ware.

The handling system 5 may be provided with a sensor for sensing the weight of an object that the handling tool 10 is attached to. For example, when the handling tool is attached to an item of crockery contaminated by food debris, the weight indicated by the sensor may beneficially be used to determine the amount of food debris attached to the crockery, or to confirm the identity of the crockery.

In the above examples the handling tool 10 has been described as transporting an item of crockery 43. However, the skilled person will appreciate that the handling tool 10 may be used to transport any other compatible items such as glassware 44 or dining trays 46.

Although the resilient skirt 14 has been illustrated as having a uniform thickness, the thickness of the resilient skirt 14 may beneficially decrease towards the outer edge of the skirt 14 to provide increased flexibility at the outer edge of the skirt 14. This allows for larger local deformations closer to the edge of the skirt 14 to improve the seal formed between the resilient skirt 14 and the object to which the handling tool 10 is attached.

The supporting part 13 may be hollow to reduce the weight of the apparatus, or may be solid in order to provide increased structural support to the resilient skirt 14.

Although the lower surface of the skirt 14 has been illustrated as being smooth, the lower surface of the skirt 14 may beneficially be textured. When the lower surface of the skirt 14 is textured, the amount of debris that moves towards the opening at the centre of the skirt when the high-power vacuum pump is switched on may be reduced. However, providing a smooth lower surface of the skirt 14 may beneficially improve the reliability of the release of wares from the handling tool, and reduce the time taken for a ware to disengage with the surface of the handling tool, when the partial vacuum between the tool 10 and the ware is destroyed.

In the above examples the resilient skirt 14 has been described as comprising a single opening for fluid flow into the conduit 12. However, the skilled person will appreciate that the resilient skirt may beneficially comprise a plurality of openings, so that fluid may flow into the conduit 12 even when one of the openings becomes blocked by debris.

Beneficially, the inner width of the conduit 12 may increase towards the opening in the skirt 14, to inhibit the formation of obstructions of the path for fluid flow. In other words, a section of the conduit 12 proximal to the opening in the skirt 14 may be tapered such that the cross sectional area of the conduit 12 increases towards the opening in the skirt 14.

Various other modifications will be apparent to those skilled in the art and will not be described in further detail here.

Claims

1. A handling tool for handling wares in a warewasher system, the handling tool comprising: means for engaging with a ware to be handled for releasably securing the handling tool to the ware for transport of the ware from a first location to a second location in the warewasher system; wherein the engaging means comprises: a resilient ware engaging plate having a ware engaging surface for mutually engaging with a surface of the ware to be handled; and means for coupling the handling tool to a vacuum source for application of at least a partial vacuum between the ware engaging surface and the surface of the ware to be handled for releasably securing the ware to the handling tool during operation; and wherein the ware engaging plate is formed of compliant resilient material whereby, in operation, the ware engaging surface will conform to a surface of the ware to be handled.

2. A handling tool as claimed in claim 1 wherein the ware engaging surface is generally planar over a greater part of the ware engaging surface when not engaged with a ware to be handled.

3. A handling tool as claimed in claim 1 or 2 wherein the ware engaging plate comprises an aperture via which said at least a partial vacuum can be applied and wherein the means for coupling comprises a conduit for forming a fluid path from the aperture to the vacuum source.

4. A handling tool as claimed in claim 3 wherein the ware engaging surface has a surface area that is greater than a transverse cross-sectional area of the aperture.

5. A handling tool as claimed in claim 4 wherein the ware engaging surface has a surface area that is at least five times the transverse cross-sectional area of the aperture, advantageously at least ten times the transverse cross-sectional area.

6. A handling tool as claimed in any of claims 3 to 5 wherein the aperture is located generally centrally to, and through the plane of, the ware engaging plate.

7. A handling tool as claimed in any of claims 3 to 6 wherein the aperture has at least one of the following geometries: circular with a diameter ~25mm to ~40mm, for example ~30mm (with tolerances of plus or minus 20%); and a transverse cross-sectional area of ~500mm² to -1250mm², for example ~700mm² (with tolerances of plus or minus 40%).

8. A handling tool as claimed in any of claims 3 to 7 wherein the ware engaging plate comprises a concave portion extending from the aperture to the ware engaging surface.

9. The handling tool as claimed in claim 8, wherein the height of the concave portion along an axis generally orthogonal to a plane of the ware engaging surface, from the ware engaging surface to the aperture, is between 5mm and 20mm (e.g. 10mm), and/or wherein the largest width of the concave portion, along an axis generally parallel to the plane of the ware engaging surface, is between 120mm and 200mm.

10. A handling tool as claimed in any of claims 3 to 9 wherein the fluid conduit is provided with a filter for inhibiting material from being drawn through the conduit towards the vacuum source.

1 1. A handling tool as claimed in claim 10 wherein the filter is formed of a metallic material.

12. A handling tool as claimed in any preceding claim wherein the ware engaging plate has a geometry (e.g. thickness and transverse cross-sectional area) whereby the ware engaging plate is sufficiently rigid to maintain a generally planar shape when not engaged with a ware, and sufficiently compliant to conform to a surface of the ware to be handled during operation to releasably secure the ware to the handling tool.

13. A handling tool as claimed in any preceding claim wherein the ware engaging plate has a thickness in the range ~1 mm to ~3mm, for example ~2mm (with tolerances of plus or minus -20%).

14. A handling tool as claimed in any preceding claim wherein the ware engaging plate has at least one of the following geometries: circular with a diameter of ~200mm to ~350mm, for example ~275mm (with tolerances of plus or minus 20%); and a transverse cross-sectional area of -30000mm² to -100000mm², for example -60000mm² (with tolerances of plus or minus 40%).

15. A handling tool as claimed in any preceding claim wherein the ware engaging plate has a transverse cross-sectional area that is configured to be similar to (e.g. within 20% of) an area of a surface, of a largest ware that the handling tool is configured to handle, which surface the ware engaging surface will engage with in operation.

16. A handling tool as claimed in any preceding claim wherein the ware engaging plate is generally disc shaped.

17. A handling tool as claimed in any preceding claim wherein the ware engaging plate is formed of a material from the list: food safe polyurethane; rubber; and silicone.

18. A handling tool as claimed in any preceding claim wherein the engaging means further comprises at least one supporting element extending from a generally central region on the ware engaging plate, whereby to provide additional rigidity across that central region.

19. A handling tool as claimed in claim 18 wherein the supporting element and the ware engaging plate are formed of the same compliant resilient material.

20. A handling tool as claimed in claim 18 wherein the supporting element is one of: frustoconical in shape; disc shaped; and hemispherical in shape.

21. A handling tool as claimed in claim 18, 19, or 20 wherein the supporting element has at least one of the following geometries at an interface with the ware engaging plate: circular with a diameter of ~100mm (with tolerances of plus or minus 20%); and a transverse cross-sectional area of -7850mm² (with tolerances of plus or minus 40%).

22. A handling tool as claimed in any of claims claim 18 to 21 wherein the supporting element has a transverse cross-sectional area that is configured to be smaller than an area of a part of a smallest ware that the handling tool is configured to handle, which part the ware engaging surface will engage with in operation.

23. A handling tool as claimed in any preceding claim further comprising a resilient mechanism configured to allow, in operation, reciprocal movement of the ware engaging plate along an axis generally orthogonal to a plane of the ware engaging plate whereby, in operation, the relative height of the ware engaging plate will adjust automatically to ware-to-ware variation in a maximum height of wares to be handled.

24. A handling tool as claimed in claim 23 wherein the resilient mechanism is further configured to allow, in operation, rotational movement of the ware engaging plate about an axis generally parallel to the plane of the ware engaging plate whereby, in operation, an angle of the ware engaging surface will adjust automatically to ware-to-ware variation in an angle of a surface of the wares to be handled.

25. Apparatus for handling wares in a warewasher system, the apparatus comprising: means for identifying a ware to be transported from a first location to a second location in the warewasher system and for determining a position of the identified ware; means for transporting the identified ware from the first location to the second location using a handling tool as claimed in any preceding claim; and a pump for providing said vacuum source for said handling tool.

26. A method of handling wares in a warewasher system using apparatus as claimed in claim 25, the method comprising: identifying a ware to be transported from a first location to a second location in the warewasher system and determining a position of the identified ware; and transporting the identified ware from the first location to the second location using a handling tool as claimed in any of claims 1 to 24.