Related Application

[001] The present invention claims priority to Singapore patent application no. 10202250825 Y filed on 25 August 2022, the disclosure of which is incorporated in its entirety.

Field of Invention

[002] The present invention relates to handling apparatuses for a dishwasher. In particular, this invention describes these handling apparatuses that are compact and occupy relatively small footprints; in addition, these apparatuses require less human labour or are provided to ease human effort during operation.

Background

[003] In large food catering systems, such as, those used in airports, hospitals, restaurants and so on, soiled dishware, including plates, cups, glasses, saucers, tray, bowls, serving trays, crockery, cutlery, and so on, are washed in industrial dishwashers. Each dishwasher uses a link conveyor to move soiled or dirty dishware from an intake end of the dishwasher through a series of washing, rinsing and drying processes, and dry, cleaned dishes are retrieved at an outlet end. Downstream of the dishwashers, human operators sort the dishware and place them on respective conveyors that lead to associated stackers, each stacker for stacking the same type of dishware. From the stackers, the cleaned dishware is transferred onto mobile galley carts for delivery to the points of use. Upstream of the dishwashers, serving trays containing soiled dishware, cutlery, food wastes, paper and plastic wastes, etc. are loaded onto feed conveyors. Along each feed conveyor, the wastes and cutlery are separated out; fragile dishware is also separated from the non-breakable dishware and is then transferred for cleaning in dedicated dishwashers. These dishwashing systems occupy large footprints, require much human labour to operate and are expensive to acquire.

[004] It can thus be seen that there exists a need for more compact dishwasher handling apparatuses. Desirably, these compact handling apparatuses have advantages over known feeding apparatuses located upstream of the dishwasher or sorting apparatuses located downstream of the dishwasher.

Summary

[005] The following presents a simplified summary to provide a basic understanding of the present invention. This summary is not an extensive overview of the present invention, and is not intended to identify key features of the invention. Rather, it is to present some of the inventive concepts of this invention in a generalised form as a prelude to the detailed description that is to follow.

[006] The present invention seeks to provide compact handling apparatuses located upstream and downstream of a dishwasher. Desirably, such compact handling apparatuses occupy relatively smaller footprints, easy to operate and require less human labour.

[007] In one embodiment, the present invention provides a dishwasher handling apparatus comprising: a dishwasher for washing dishware; upstream dishware handling apparatuses disposed upstream of the dishwasher; and downstream dishware handling apparatuses disposed downstream of the dishwasher; wherein, the dishware at both the upstream and downstream dishware handling apparatuses are stored in vertical stacks before washing and after washing, so that the dishwashing apparatus is compact and occupy a relatively small footprint, compared to a conventional dishwasher.

[008] Preferably, each dishware comprises a ferrous element embedded or attached at a base surface, or comprises a ferritic material, and wherein notches are formed at a bottom rim of each dishware.

[009] Preferably, the upstream dishware handling apparatuses comprise: a multi-storey shelf having a supply shelf and a storage shelf located above or below the supply shelf, wherein the supply shelf is configured with a powered conveyor via which a stack of dirty dishware is being supplied and waits to be transferred for cleaning; and a conveyor elevator with a substantially vertical moveable platform for docking with the multi-storey shelf, wherein a selected stack of dirty dishware stored on the storage shelf is operable to be transferred by the conveyor elevator docking with the powered conveyor located at the supply shelf. [0010] Preferably, a liquid spraying apparatus is located at an entry end of the supply shelf or an exit end of the storage shelf.

[0011] Preferably, the dishwasher handling apparatus further comprises a rinsing robot to rinse a dishware before feeding the dishware into the dishwater. Preferably, the rinsing robot comprises an indexable rotary member with equally spaced arms, with 3 of the rotary arms defining a dish loading station, a rinsing station and a dish unloading station. The dish unloading station may comprise a lifter fork that is operable to move between a home position and an extended position, such that when a dishware is supported on the lifter fork at the extended position, the dishware is lifted above a top of the rotary arm present at the dish unloading station.

[0012] Preferably, a robot is located upstream of the rinsing robot for picking a dishware from the powered conveyor and to load the dishware at the dish loading station; and another robot is located downstream of the rinsing robot for unloading a dishware at the dish unloading station. The ends of both the rotary arms and the robots are configured with an end-effector for picking or placing a dishware at a desired location and orientation. The rinsing station may comprise a rotary brush and spray nozzles.

[0013] Preferably, the downstream dishware handling apparatuses comprise: a downstream multi-storey shelf having a sorting shelf and a storage shelf located above or below the sorting shelf, wherein the sorting shelf is configured with a powered conveyor for receiving cleanly washed dishware, which dishware are then stored up in a vertical stack with the dishware being inverted; and a conveyor elevator with a substantially vertical moveable platform for docking with the downstream multi-storey shelf, wherein the cleanly washed dishware stack is operable to be transferred by the conveyor elevator by docking with the downstream multi-storey shelf. A handling robot is located between the dishwater and the downstream multi-storey shelf, wherein an end-effector is operable to transfer a dishware therebetween.

[0014] Preferably, the conveyor elevator or the storage shelf further comprises a roller conveyor or a powered conveyor. The powered conveyor can be configured by a belt conveyor, a powered toller conveyor or a walking conveyor. [0015] Preferably, the above handling robot can be configured by a gantry robot, a scara robot, a robot manipulator, a serial manipulator, a parallel manipulator or any robot equipped with articulated arms and joints. Preferably, each gantry robot comprises a horizontal member operable to provide an X-axis movement substantially parallel to the conveyor belt and a vertical member to provide vertical Z-axis movement. It is also possible to provide an additional member to provide XYZ axes movements.

[0016] Preferably, the end-effector comprises a magnetic mechanism or a pneumatic suction cup mechanism. The magnetic mechanism may comprise a magnet or magnets that is/are moveable between a magnetic attraction position and a magnetic release position by one of the following mechanisms: a slide assembly operable by a rack-and-pinion sub-assembly; a rotatory holder operable by a rotary actuator; a plunger operable by a solenoid or a piston rod; an arm indexably operable by a geared-actuator assembly; a slide assembly operable by a leadscrew and nut; or a slide assembly operable by a fluid cylinder.

[0017] In another embodiment, the present invention provides a rinsing robot configured for dishwashing; the rinsing robot comprises: an indexable rotary member having equally spaced radiating arms, with three of the radiating arms defining a dish loading station, a rinsing station and a dish unloading station, with the dishware unloading station being located substantially at the 12 o’clock position; and an end-effector for picking or releasing a dishware is located at a terminal end of each radiating arm.

[0018] Preferably, each end-effector of the rinsing robot is configured with a pneumatic suction cup or a magnetic grabbing/releasing mechanism.

[0019] In another embodiment, the present invention provides a method for operating a dishwasher, the method comprises: storing dishware for washing in a vertical stack on a multi-storey shelf, wherein a supply shelf is configured with a powered conveyor; docking a conveyor elevator with the multi-storey shelf so that a stack of the dishware is operable to be transferred onto the powered conveyor; picking a dishware from a stacked dishware on the powered conveyor and transferring the dishware to the dishwasher; unloading the newly washed dishware from the dishwasher and stacking the newly washed dishware in a vertical stack on a powered conveyor configured on a sorting shelf of a downstream multi-storey shelf; and docking a conveyor elevator with the powered conveyor and transferring a stack of the newly washed dishware onto a storage shelf level of the downstream multi-storey shelf, from which the newly washed dishware is collected and delivered to a place for use.

[0020] Preferably, the method further comprises: transferring the dishware from the powered conveyor to a rotary rinsing robot; and indexing the rotary rinsing robot in the following cyclic steps: loading a dishware into a dish loading station of the rotary rinsing robot; rotating a brush on the dishware at a rinsing station of the rotary rinsing robot; and unloading the dishware at a dish unloading station of the rotary rinsing robot into the dishwasher.

[0021] Preferably, the method comprises transferring the dishware by operating a handling robot located between the belt conveyor and the rinsing robot or between the rinsing robot and the dishwasher, or comprises transferring the newly washed dishware between the dishwasher and the downstream multi-storey shelf.

Brief Description of the Drawings

[0022] This invention will be described by way of non-limiting embodiments of the present invention, with reference to the accompanying drawings, in which:

[0023] FIGs. 1-4 illustrate some types of dishware that can be used with handling apparatuses of the present invention and an associated dishwasher, whilst FIG. 5 illustrates a bottom view of a dishware shown in FIGs. 1-4;

[0024] FIG. 6 illustrates a system of dishware handling apparatuses and an associated dishwasher according to an embodiment of the present invention; whilst FIGs. 7 and 8, respectively, illustrate enlarged parts of the dishware handling apparatuses located upstream and downstream of the dishwasher;

[0025] FIGs. 9 and 10 illustrate spraying apparatuses to wet stacks of dirty dishware waiting to be cleaned;

[0026] FIGs. 11-17 illustrate various steps of operations of a rinsing robot; [0027] FIG. 18 illustrates dishware handling with a fork lifter at a dish unloading station;

[0028] FIGs. 19-28 illustrate structural mechanisms of magnetic end-effectors for picking or placing a dishware;

[0029] FIG. 29 illustrates an indexable rotary member of a rinsing robot according to another embodiment; and

[0030] FIG. 30 illustrates an upstream dishware handling apparatus according to a variation of the apparatus shown in FIG. 6 or 7.

Detailed Description

[0031] One or more specific and alternative embodiments of the present invention will now be described with reference to the attached drawings. It shall be apparent to one skilled in the art, however, that this invention may be practised without such specific details. Some of the details may not be described at length so as not to obscure the present invention.

[0032] FIGs. 1-4 show various types of dishware 10 that can be used with the present invention. As shown in FIGs. 1-3, the dishware 10 may be a plate 11, a bowl 12, a saucer 13, and so on; these types of dishware 10 may be made of a non-magnetic material, such as, ceramic, stone, plastic, melamine, wood, aluminium, etc.. At a base 22 on the underside of the dishware 10, plate 11, bowl 12, saucer 13, is embedded or attached a ferrous element 20, which is magnetizable. In one embodiment, the ferrous element 20 is embedded in the base 22 of the dishware 10, as shown in FIGs. 1-3, such that the base 22 is substantively flat. In another embodiment, the ferrous element 20 is attached, for eg. adhesively as shown in FIG. 5, onto the base 22 of the dishware 10. FIG. 4 shows another dishware 14, for eg. made of a ferritic material, which may be an iron or steel, for example, coated with an enamel to prevent corrosion. In use, an end-effector 300, which will be described, is moved to pick or to place the dishware 10, plate 11, bowl 12, saucer 13 or dishware 14. In one embodiment, the endeffector 300 is connected to a component of a dishwasher handling apparatus 100 through a pivot joint 302 and the pivot joint is rotatable by an actuator, so that the dishware can be picked up or placed at a desired location or orientation. The ferrous material 20 also helps to define a centre at the base 22 to give consistent handling of the dishware 10,14. With this invention, handling of the dishware 10,14 can be automated or semi-automated.

[0033] FIG. 5 shows a bottom view of the dishware 10,14. The bottom face at the base 22 of each of the dishware 10,14 is usually formed with a rim. In one embodiment, a notch 24 is or multiple notches 24 are formed at the rim. When the dishware 10,14 is wetted, the notches 24 allow water or washing liquid to flow over the dishware 10,14; this ensures that the bottom face can also be wetted even when the dishware is stacked up; conversely, after washing, water can flow through the notches 24 when the dishware 10,14 is arranged to drain out the water.

[0034] FIG. 6 shows dishware handling apparatuses 101,201 located upstream and downstream of a dishwasher 30 according to an embodiment of the dishwasher handling apparatus 100. The upstream dishware handling apparatus 101, as shown at the left-hand side of FIG. 6, is illustrated at a larger scale in FIG. 7. Similarly, the downstream dishware handling apparatus 201 at the right-hand side of FIG. 6, is illustrated at a larger scale in FIG. 8. The dishwasher 30 may be a known type and is selected to provide, for example, washing, scrubbing, rinsing and drying of the dishware 10,14, that are fed in from the upstream dishware handling apparatus 101 and are sorted out by the downstream dishware handling apparatus 201.

[0035] As can be seen from FIGs. 6 and 7, the upstream dishware handling apparatus 101 include a multi-storey shelf 110, a conveyor elevator 130, a rinsing robot 150 and two gantry robots 170,180 located on each side of the rinsing robot 150 according to one embodiment. In the present invention, the dishware 10,14 are stored in vertical stacks 105 to some predetermined heights on the multi-storey shelf 110; this allows the upstream dishware handling apparatus 101 to occupy a relatively smaller footprint, compared to footprint of the conventional handling apparatus.

[0036] As shown, the multi-storey shelf 110 includes multiple shelves 112 being supported by some vertical columns 111. For eg., in FIG. 7, the multi-storey shelf 110 is shown to comprise of 4 shelf levels. In one embodiment, as shown in FIG. 6 or 7, shelf level 3 (now called supply shelf) is at an ergonomic height and it is configured with a powered conveyor 120 which extends out of the multi-storey shelf 110 at an end proximal to the rinsing robot 150. Shelf levels 1, 2 and 4 (now called storage shelves) can each be configured with a roller conveyor 120a or a powered conveyor 120. In one embodiment, the above powered conveyor can be configured as a belt conveyor, powered walking conveyor or a powered roller conveyor, if fully automation is desired; if semi-automation is desired, shelf levels 1,2 and 4 (or storage shelves) can be configured with a section of powered conveyor or a section of powered rollers at each shelf level. In one embodiment, dirty dishware 10,14 to be cleaned are stacked 105 on separate storage shelf levels 1, 2, 4 according to the types of dishware. As seen in FIGs. 6 and 7, the conveyor elevator 130 is equipped with a vertically moveable elevator platform 132 and is located on the left-hand side of the multi-storey shelf 110, so that the elevator platform 132 can dock at a selected shelf level. The elevator platform 132 is also configured with a powered conveyor or powered rollers. In use, a stack 105 of dirty dishware 10,14 stored on a storage shelf level on the multi-storey shelf 110 is operable to be transferred, one stack 105 at a time, onto the elevator platform 132 that has docked therewith; when a stack 105 of dishware is ready to be cleaned, the stack 105 of dishware on the elevator platform 132 is moved to dock with the powered conveyor 120 at the supply shelf, and the stack 105 of dirty dishware is then transferred thereon. In another embodiment, stacks of dishware 10,14 can be transferred onto the powered conveyor 120, to form a queue, while waiting for the dirty dishware 10, 14 to be transferred, one dish at a time, by the gantry robot 170 to the rinsing robot 150.

[0037] As shown in FIGs. 6 and 7, a spray apparatus 140 is located at an entry end of the powered conveyor 120 or roller conveyor 120a. The spray apparatus 140 is shown in FIG. 9 to include a U-frame 142 and spray nozzles 144 are disposed along two sides of the U-frame 142. Not shown in FIG. 9 are tubings connecting the U-frame 142 to a pump to deliver water or cleaning liquid to wet the stack 105 of dirty dishware 10,14 as the dishware 10,14 is being transferred onto the powered conveyor 120 or the roller conveyor 120a. Also not shown is a tray disposed below the powered conveyor 120 or the roller conveyor 120a to collect the sprayed water for discharge or for recycling. With this spray apparatus 140, the stack 105 of dirty dishware 10,14 is kept in a wet condition for easy pre-wash at the rinsing robot 150, as the dishware 10,14 are uprightly stacked up and the notches 24 allow the bases 22 of the dishware 10,14 to be wetted.

[0038] FIG. 10 shows a similar spray apparatus 140 that can be located at exit ends at the various storage shelf levels 1,2 or 4 on the multi-storey shelf 110 to spray water or washing liquid onto the stacks 105 of the dirty dishware 10, 14 that are waiting to be transferred to the powered conveyor 120a and the rinsing robot 150.

[0039] Now, referring back to FIG. 6, the right-hand side shows the downstream dishware handling apparatus 201. The downstream dishware handling apparatus 201, also shown in FIG. 8, includes an unload gantry robot 280, a multi-storey shelf 210 and a conveyor elevator 230. The multi-storey shelf 210 is configured with a structure similar to that of multi-storey shelf 110. The conveyor elevator 230 is also configured with a structure similar to that of the conveyor elevator 130. The directions of operating powered conveyors located on the multistorey shelf 210 and the conveyor elevator 230 differ from those corresponding counterparts at the upstream side and are implemented, for eg., by mere electric wiring changes. Applicant believes that the above descriptions of the multi-storey shelf 110 and the conveyor elevator 130 are applicable to the downstream counterparts and no further descriptions of the multistorey shelf 210 and the conveyor elevator 230 are deemed necessary.

[0040] Referring back to FIG. 7, the gantry robot 170 includes a horizontal member 172 that is arranged substantially parallel to the conveyor belt 120; a vertical member 174 is moveable on the horizontal member 172, and the end-effector 300 is located at a lower end of the vertical member 174 via the pivot joint 302. The horizontal and vertical members 172,174 are equipped with known linear motion elements and position sensors, and these known elements/sensors are thus not further described. It is also possible that a known camera (such as, a RGB camera, a RGB-D camera, or any similar type camera) is provided on the endeffector 300 (in a so-called eye-in-hand configuration) or a camera provided on the gantry robot 170 (in a so-called eye-to-hand configuration) to help detect a position and a height of the stacked 105 dishware that is to be cleaned or being cleaned. The pivot joint 302 is pivotable by a known actuator, preferably being equipped with a rotary encoder for positioning control.

[0041] In one embodiment, the end-effector 300 is equipped with a pneumatic suction cup; in another embodiment, the end-effector 300 is equipped with a magnet M, which is employed to pick or to place a dishware 10,14, as illustrated in FIG. 11. Various mechanisms for effecting the magnet M to pick or to place a dishware 10,14 will be described with FIGs. 19-28, after describing operations of the gantry robots 170, 180 and the rinsing robot 150. [0042] As can be visualised from FIG. 7, the end-effector 300 is moved to a position above the stacked 105 dishware 10,14 and is lowered onto a centre of a dishware from the top; the magnet M inside the end-effector 300 is actuated to pick and to transfer the dishware 10,14 to the rinsing robot 150, also as seen in FIG. 12.

[0043] In one embodiment, the rinsing robot 150 includes a cross-shaped rotatory member 151 having 4 extending arms 152. The free ends of each arm 152 is internally configured with the end-effector 300. The cross-shaped rotatory member 151 is arranged to index by a quarter-turn step in a rotatory manner where the arms 152 are aligned at the 12, 3, 6 and 9 o’clock positions. The rinsing robot 150 has 3 stations: a dish loading station 153, a scrubbing station 154 and dish unloading station 155. The dish loading station 153, scrubbing station 154 and dish unloading station 155 are located, respectively, at the 9, 6 and 12 o’clock positions. After a process time T at the rinsing robot 150 is completed, the rotary member 151 indexes cyclically in substantially quarter-turn steps. The process time T may be determined by a cycle time at the scrubbing station 154 or the dish unloading station 155.

[0044] For ease of description, operations of the rinsing robot 150 are now described sequentially from the dish loading, scrubbing and dish unloading stations. Arrows in the drawings indicate transfers of the dishware 10,14, motions of the end-effectors 300, stations, components, and so on. At the dish loading station 153, the gantry robot 170 transfers the dishware 10,14 with the end-effector 300 on the gantry robot 170 to the end-effector 300 located at the arm 152 of the rinsing robot 150. When the cycle time T at both the scrubbing and dish unloading station are completed, the rinsing robot 150 indexes substantially a quarter-turn, as seen in FIG. 12 in an anti-clockwise direction, thereby moving the dirty dishware 10,14 into the scrubbing station 154. At the scrubbing station 154, a scrubber 108 is actuated to rotate and to move into contact with an inside surface of the dishware 10,14; at the same time, spray nozzles 144 spray water or cleaning liquid at the dishware to rinse off any food particles, oil or grime from the dishware 10,14 with the help of the scrubber 108.

[0045] Whilst the scrubbing station 154 is in operation, the end-effector 300 at the gantry robot 170 loads another dishware 10,14 to the end-effector at the arm 152 at the dish loading station 153. The processes at the dish loading station 152 and the scrubbing station 154 go on, and after three cycles, the first dishware 10,14 is transferred into the dish unloading station 155, as seen in FIG. 13. [0046] At the dish unloading station 155, a lifter fork 160 is aligned with an arm 152 of the rinsing robot 150. The structure of the lifter fork 160 shown in FIG. 18 will be described below. At the dish unloading station 155, the lifter fork 160 is actuated to extend upwards, as seen in FIG. 14, thereby detaching the dishware 10,14 from the end-effector 300 located at the arm 152 and the dishware 10,14 is then supported by gravity force on the lifter fork 160; the end-effector 300 of the gantry robot 180 is then moved into a position below the lifter fork 160; the end-effector 300 of the gantry robot 180 is moved into contact with the base of the dishware 10,14 and is actuated to hold the dishware 10,14, as seen in FIG. 15. In FIG. 16, the end-effector 300 of the gantry robot 180 is moved out of the dish unloading station 155. In the following process, in FIG. 17, the lifter fork 160 is actuated to return to its home position, and the gantry robot 180 continues to move to place the partially cleaned dishware 10,14 onto the conveyor 40 of the dishwasher 30, preferably, with the dishware 10,14 in an inverted and slanting position, as each dishware 10,14 is held in position by the finger-like projections 42 extending from the dishwasher conveyor 40; in this inverted and slanting position, the base of the dishware 10,14 is reachable from above by an end-effector 300 of the gantry robot 280 located downstream of the dishwasher 30.

[0047] FIG. 18 shows the lifter fork 160 in alignment with the rotatory member 151 of the rinsing robot 150. The lifter fork 160 is U-shaped and a longitudinal U-opening 162 is wide W enough to accommodate a thickness of the arm 152 of the rotatory member 151. In one embodiment, the lifter fork 160 is guided to translate in a substantially vertical manner by a pair of rods 164. Whilst shown schematically, an actuator 166 is provided to move the lifter fork 160 between the home position and an extended position at the dish unloading station 155. The extended position is located above atop of the arm 152 at the dish unloading station 155. In another embodiment, a top surface of the lifter fork 160 which contacts with the dishware 10,14 is provided with a membrane NP; the membrane NP may be a rubber, a polyurethane, or similar material, which provides a cushioned contact between the lifter fork 160 and the dishware 10,14; in addition, membrane NP also provides friction to prevent the dishware 10,14 from slipping on the lifter fork 160. The membrane NP can be adhesive attached or coated onto the lifter fork 160.

[0048] Now referring back to FIG. 8, it shows the dishware handling apparatus 201 located downstream of the dishwasher 30. At the outlet end of the dishwasher 30, the dishware 10,14 on the dishwasher conveyor 40 are also inverted in a slanting orientation as held by the finger-like projections 42. The end-effector 300 of the gantry robot 280 contacts the base of each of the dishware 10,14 and transfers a dishware 10,14, one at a time, onto a powered conveyor 220 located on a sorting shelf level of the downstream multi-storey shelf 210. The cleaned dishware is now stacked 107 up, in an inverted manner, according to the types of dishware, so that the plates 11, bowls 12, saucers 13, metal dish 14, etc. are stored in separate vertical stacks 107. The downstream multi-storey shelf 210 and the conveyor elevator 230 and associated conveyor platform 232 are structurally similar to that of the counterpart multistorey shelf 110 and the conveyor elevator 130 located at the upstream side, thus, no further descriptions are provided. Briefly, the stacks 107 of cleaned dishware 10,14 are moved from the powered conveyor 220 onto predetermined storage shelves 212 by operating the conveyor elevator 230; the stacks 107 of dishware can then be transferred to a point of use, according to demand, for eg. by using a delivery trolley.

[0049] In the above figures, the upstream and downstream dishware handling apparatuses 101,201 are aligned in a row with the dishwasher 30. In another embodiment, the upstream and downstream handling apparatuses need not be aligned in a row with the dishwasher 30, for eg., by providing an addition Y-axis to the gantry robots 170,180,280. In this way, the dishware handling system 100 and dishwasher 30 can be arranged to fit a given space layout.

[0050] In the above, the gantry robots 170,180,280 have been described. It is possible that other alternative types of handling robots can also be used to transfer the dishware 10,14 between stations at the upstream and downstream dish handling apparatuses 101,201. For eg., these alternative handling robots may be: scara robots, robot manipulators, serial manipulators, parallel manipulators, or any robot with articulated arms and joints. It is also possible that bases of these robots are mounted on a ground, a wall or an overhead structure.

[0051] Now, structures of the end-effector 300 according to various embodiments are described. The effector 300 can be configured by at least 4 mechanisms, namely, a slide assembly operable by a rack-and-pinion sub-assembly 310, a rotary holder 322-actuator assembly 300-1, an eject or- solenoid assembly 300-2, and a magnet-geared motor assembly 300-3. FIG. 19 shows the end-effector 300 is configured with the rack-and-pinion assembly 310. The end-effector 300 is made up of the rack-and-pinion assembly 310 disposed inside a hollow member 312 and is held to slide by a linear rail 314-slide 316 mechanism. As seen in FIG. 19, the right-hand end of the hollow member 312 is closed with an end-face 313 to support a membrane NP. The hollow member 312 and the end-face 313 are made of a nonmagnetic material; the end-face 313 is relatively thin but structurally strong enough to support an attached dishware 10,14. Not shown is a rotary actuator connectable to a pinion 311 to move the magnet M towards or away from the end-face 313. When the magnet M is moved to a position near or in contact with the end-face 313, the distance between the magnet M and the dishware 10,14 is minimal and the magnetic attraction force on the dishware 10,14 becomes strong enough to hold the dishware 10,14, as the dishware is being moved or transferred by the upstream and the downstream dishware handling apparatuses 101,201; when the magnet M is retracted, the distance between the magnet M and the end-face 313 becomes too far for the magnetic attraction force to be effective; thus, when the magnet M is retracted, the end-effector 300 is operable to release an attached dishware 10, 14 by placing it at a desired location and orientation.

[0052] FIGs. 20 and 21 show an end-effector 300-1 according to another embodiment. As shown, the end-effector 300-1 is made up of a magnet M being held in a rotary holder 322, with the rotary holder being supported by a body member 320. Both the rotary holder 322 and the body member 320 are made of a non-magnetic material. As seen in the figures, a lower face of the body member 320 has a membrane NP, which may be adhesively attached or coated thereon. In FIG. 20, the magnet M is positioned adjacent to a dishware 10,14 and the distance between the magnet M and dishware is small enough to put the magnet M in a state of grabbing the dishware 10,14. In FIG. 21, the magnet M is rotated away from the dishware 10,14 and the magnet M is rotated into a release state.

[0053] FIGs. 22 and 23 show an end-effector 300-2 according to another embodiment. The end-effector 300-2 is made up of a magnet M disposed near a face 332 of a body member 330. The face 332 has a membrane NP being adhesively attached or coated thereon. Preferably, a pair of ejectors 334 coupled with actuating solenoids SS are arranged substantially perpendicular to the face 332. When the end-effector 300-2 is to pick up a dishware 10, 14, the face 332 with the membrane NP is moved proximal to the dishware with the ejectors 334 being retracted into the body member 330 so that the magnet M is put in a grabbing state of attracting the dishware 10,14; when the effector 300-2 is to release or to place a dishware 10,14, the ejectors 334 are actuated to extend out of the body member 330, in a release state. [0054] FIGs. 24-28 show an end-effector 300-3 according to yet another embodiment. As shown in FIGs. 24-28, two pairs of magnets M are operable on separate actuating arms to index between an attraction or grabbing state and a release state by a geared-actuator assembly. In one embodiment, an actuator 360 is connected through gears 362 to index the pair of magnets M between the attraction state and the release state. In the attraction state, a distance between the magnet M from a support plate 364 is minimal, and the magnet attraction force acts on the ferrous member 20 located at the base of the dishware 10 for picking or directly on the ferritic dishware 14; in the release state, the distance between the magnet M and the ferrous element 20 or the ferritic dishware 14 is too far for the magnet to attract, thereby, allowing the dishware 10,14 to be placed at a desired position and orientation. FIG. 25 shows a side view of the end-effector 300-3 in a grabbing state, whilst FIG. 26 shows an end view thereof. In FIGs. 27 and 28, the magnets M have been rotated through a quarter-turn by the geared-actuator and are shown in the release state. In the above FIGs. 24-28, adjacent magnets M located on separate actuating arms are arranged such that the poles on the two opposite pairs are unlike poles. In another embodiment, adjacent magnets M arranged on the two opposite actuating arms are like poles.

[0055] Depending on the strengths of the magnets M, it is possible that only one actuator arm with a magnet M or a pair of magnet M is employed in the embodiment 300-3 shown in FIGs. 24-28. It is also possible that the pair of magnets M on one actuating arm are arranged in the same orientation with like or unlike poles.

[0056] The above end-effector 300 has been described to be configured with a rack-and- pinion assembly 310. In another embodiment, an alternative to the rack-and-pinion assembly 310 is a leadscrew-nut assembly; in use, the leadscrew-nut assembly is operable to move the magnet M close to or away from the end-face 313, so as to pick/grab or to place/release a dishware 10,14. In yet another embodiment, movement of the magnet M close to or away from the end-face 313 is also operable by a fluid cylinder, such as, a pneumatic cylinder. In addition, it is also possible that the above ejector 334 can be configured by a piston rod of a fluid cylinder. [0057] With the end-effectors 300,300-1,300-2,300-3 of the present invention, the endeffectors can be actuated to pick/grab or to place/release a dishware 10,14 at a desired position and orientation, thus allowing automation or semi-automation of the above system 100. Automation or semi-automation helps to reduce human labour or to ease human efforts in operating the above system 100.

[0058] In the above description, the dishwasher 30 may employ waterj et cleaning, mechanical scrubbing, ultrasonic scrubbing, and so on, depending on uses of the dishware 10,11-14; it is then possible that the rinsing robot 150 is superfluous in some applications. FIG. 30 shows an upstream dishware handling apparatus 101a according to another embodiment of the present invention; as shown in FIG. 30, the upstream dishware handling apparatus 101a includes the upstream multi-storey shelf 110 and the associated conveyor elevator 130, and a handling robot 170a; for simplicity, the handling robot 170a is illustrated with components of the above gantry robot 170. As described above, above gantry robot 170,180,280 may be any one of these types: scara robot, robot manipulator, serial manipulator, parallel manipulator, or any robot with articulated arms and joints. Thus, the handling robot 170a may be configured like any one of these scara robots, robot manipulators, serial manipulators, parallel manipulators or articulated robots; therefore, for clarity of disclosure, the above gantry robots 170,180,280 are now referred to generally as handling robots, be they located upstream or downstream of the dishwasher 30.

[0059] While specific embodiments have been described and illustrated, it is understood that many changes, modifications, variations and combinations of variations disclosed in the text description and drawings thereof could be made to the present invention without departing from the scope of the present invention. For example, FIG. 29 shows an indexable rotary member 451 having 3 equally spaced arms 452 according to another embodiment 400. As in the above embodiment, the ends of the arms 452 are equipped with the above magnetic mechanisms of the end-effectors 300 or suction cups. The arms 452 define a dish loading station 453, a rinsing station 454 and a dish unloading station 455, which are similar to stations described above; preferably, the dish unloading station 455 also at a 12 o’clock position, at which a dishware 10,14 is detachable from a fork lifter 460 that is similar to the above lifter fork 160 above.