Field of the Invention

[1] The present invention relates to an automated punnets handling assembly.

Background of the Invention

[2] Packing plastic punnets filled with product (typically fruit such as blueberries, strawberries, etc.) into cardboard boxes or plastic cases/trays for distribution and transport to supermarkets and markets presently has a number of difficulties.

[3] Present punnet handling assemblies can damage the product as they apply a mechanical force to grip the punnets. An alternative is using vacuum force to lift the punnets via the lids which also can lead to damage as the lid can pop open, especially as punnet lids are designed to be opened by applying a force to the sides of the punnets.

[4] The present invention seeks to overcome or substantially ameliorate at least some of the deficiencies of the prior art, or to at least provide an alternative.

[5] It is to be understood that, if any prior art information is referred to herein, such reference does not constitute an admission that the information forms part of the common general knowledge in the art, in Australia or any other country.

Summary of the Invention

[6] According to a first aspect, the present invention provides an assembly for automatic handling of punnets into a tray, the assembly comprising: a conveyor with at least one conveyor lane for transporting a series of punnets, the conveyor having spacing assemblies for each conveyor lane which separates the punnets into predetermined groups, a robotic arm holding a fork, the fork including a base and a series of spaced fork tines extending from the base, the fork tines extending in a direction which is perpendicular to the travel direction of the conveyor lanes such that the robotic arm can move the fork for engaging the punnet groups and lifting the punnets groups from the conveyor to a tray.

[7] In one embodiment, the spacing assemblies form the punnet groups by holding punnets in defined cell positions whilst a conveyor belt of the conveyor lane continually moves underneath the punnets. [8] In another embodiment, the assembly comprises two or more conveyor lanes which are parallel.

[9] In another embodiment, the spacing assemblies comprise stopper pairs of a first stopper bar and a second stopper bar both disposed to extend vertically, the first stopper bar having a first distal end portion and the second stopper bar having a second distal end portion, wherein the first and second distal end portions have an initial lowered position below an upper surface of the respective conveyor belt, and the first stopper bar and the second stopper bar are respectively actuatable by respective actuators such that the first distal end portion and the second distal end portion extend above the upper surface of the respective conveyor belt, which defines a raised position of the first stopper bar and the second stopper bar.

[10] In another embodiment, the first stopper bar is extendable such that the first distal end portion engages a lower well of a punnet, and the second stopper bar is extendable such that the second distal end portion engages a flange of the punnet.

[11 ] In another embodiment, each conveyor lane includes two stopper pairs for each predetermined group, each stopper pair being disposed adjacent a respective side edge of the conveyor belt.

[12] In another embodiment, the stopper pairs are disposed to stop the lead punnet in each group to hold the group in the respective cell position.

[13] In another embodiment, the spacing assemblies are disposed such that the groups are spaced from each other.

[14] In another embodiment, the assembly further comprises guide rails for the conveyor for guiding the punnets therealong, wherein guide rails that can impede the fork are retractable downwardly to a lowered position once the punnet groups are formed.

[15] In another embodiment, the fork tines are adapted to engage flanges of the punnets.

[16] In another embodiment, the assembly further includes unloading tabs which are moved up to extend vertically, from below and adjacent the base, and between the fork tines, such that when the robotic arm is withdrawn or moves back, the punnets can engage the unloading tabs and ensure unloading from the fork tines.

[17] Preferably, the unloading tabs are mounted to a bar which is actuatable to move in the vertical direction for moving the unloading tabs up and down, the unloading tabs being in the lowered position initially by default and are raised to assist in the unloading. [19] In another embodiment, the assembly further comprises lid sensors which can detect if any punnet lids are open. Alternatively, this function can be performed with a vision system.

[20] In another embodiment, the assembly further comprises rotation sensors which can detect if any of punnets are rotated from required orientation thereof.

[21] In another embodiment, the assembly further comprises a reject chute for removing unwanted punnets from the conveyor.

[22] The invention in another aspect provides a method of automatic handling of punnets into a tray, the method comprising: transporting a series of punnets along a conveyor with at least one conveyor lane, spacing the punnets into predetermined groups via spacing assemblies of the conveyor, engaging the punnets via their flanges with a fork held by a robotic arm, the fork including a base and a series of spaced fork tines extending from the base in a direction which is perpendicular to the travel direction of the conveyor lanes.

[23] Preferably, the spacing assemblies form the punnet groups by holding punnets in defined cell positions whilst a conveyor belt of the conveyor lane continually moves underneath the punnets.

[24] Preferably, the spacing assemblies stop a punnet by engaging a lower well of a punnet.

[25] Preferably, the spacing assemblies then engage a flange of the punnet.

[26] Other aspects of the invention are also disclosed.

Brief Description of the Drawings

[27] Notwithstanding any other forms which may fall within the scope of the present invention, preferred embodiments of the present invention will now be described, by way of examples only, with reference to the accompanying drawings in which:

[28] Figure 1 shows a robotic pick area of an assembly according to a preferred embodiment of the present invention,

[29] Figure 2 shows spaced groups of punnets in the conveyor lanes,

[30] Figure 3 is a top view of two conveyor lanes,

[31 ] Figure 4 is a side view showing a spacing assembly,

[32] Figures 5 and 6 show an example run of spacing punnets in use,

[33] Figure 7 shows raising of the first stopper bar of the spacing assembly,

[34] Figure 8 shows raising of the second stopper bar of the spacing assembly, [35] Figure 9 shows lowering of the first stopper bar of the spacing assembly,

[36] Figures 10 and 11 show the spaced groups of punnets,

[37] Figures 12 to 18 show the steps in insertion of the fork tines to handle and raise the punnets and moving the punnets onto trays,

[38] Figures 19 and 20 show hatch doors at the distal end of the conveyor and reject chutes,

[39] Figure 21 (a) to (f) shows unloading tabs which assist in unloading the punnets from the fork tines.

Description of Embodiments

[40] It should be noted in the following description that like or the same reference numerals in different embodiments denote the same or similar features.

[41 ] Figure 1 shows a robotic pick area of an assembly 10 for automatic handling of punnets 100 into a box or tray 200. The assembly 10 includes a packing conveyor 1 1 with conveyor lanes 12, which in the example comprises two conveyor lanes 12a and 12b. The conveyor lanes 12 are parallel and define a direction of travel (bidirectional) indicated by arrow 13.

[42] The assembly 10 further includes a robotic arm 80 which is disposed adjacent a first side edge of the packing conveyor 11 . The robotic arm 80 holds a fork 81 . The fork 81 includes a base 82 which extends along the length of the first side edge of the packing conveyor 11 . The fork 81 further includes a series of spaced fork tines 83 extending from the base 82, the fork tines 83 extending in a direction 14 which is perpendicular to the travel direction 13 of the conveyor lanes 12. In use, the robotic arm 80 moves the fork tines 83 along a plane in the direction 14 for engaging the punnets 100 and lifting the punnets 100 from the conveyor lanes 12 for transfer to a box or tray 200, or to another station/conveyor as needed.

[43] Referring to Figure 2, the packing conveyor 1 1 comprise spacing assemblies 20 for each conveyor lane 12 which separates the punnets 100 into groups 70. The punnet groups 70 are held in defined cell positions 72 by the spacing assemblies 20 whilst the belts 16 of the conveyor lanes 12 continually move underneath the punnets 100. The punnet groups 70 are then engaged by the fork 81 for moving onto a package box or tray 200. In the example shown, the punnets 70 are spaced into a number of groups 70 which in the example are four groups 70a to 70d in the respective cell positions 72a to 72d.

[44] As shown in Figure 3, the conveyor lanes 12 each comprise a conveyor belt 16 which in the example are made from plastics coated material. The conveyor belts 16 transport the punnets 100 therewith but also allows the punnets 100 to be stopped and held in their required positions with the conveyor belts 16 continually running underneath the punnets 100. The conveyor belts 16 have a width which is less than the width of the punnets 100. [45] As shown in Figures 3 and 4, the spacing assemblies 20 comprise stopper pairs 40 of a first stopper bar 42 and a second stopper bar 44. Each conveyor lane 12 includes two stopper pairs 40, each stopper pair 40 disposed adjacent a respective side edge of the conveyor belt 12. The two stopper pairs 40 with the conveyor belt 16 therebetween extend substantially the width of the punnets 70 in each conveyor lane 12.

[46] The stopper pairs 40 are disposed to stop the lead punnet 100 in each group 70 to hold the group 70 in the respective cell position 72. In the example shown which provides four cells positions 72 and thus four groups 70, each conveyor lane 12 will have four groups of spacing assemblies 20 along the length of the conveyor lane 12. The spacing assemblies 20 are disposed such that the groups 70 are spaced from each other - that is, the lead punnet 100 in each group is spaced from the last punnet in the next group.

[47] The assembly 10 includes sensors 90 and a control center which is programmed to performs the required counts of the punnets 100 and operation of the robotic arm 80.

[48] As shown in Figures 5 and 6, in an (example only) operation run of twelve punnets 100 in each conveyor lane 12 moving in direction 13, the punnets 100 will be stopped to be separated into four groups of three punnets 70 each for each cell position 72. The stopper pairs 40 of cell position 72d will stop the 10 ^th punnet 100, such that the cell position 72d has the 10 ^th to 12 ^th punnet group 70. The stopper pairs 40 of cell position 72c will then stop the 7 ^th punnet 100, such that the cell position 72c has the 7 ^th to 9 ^th punnet group 70. The stopper pairs 40 of cell position 72b will then stop the 4 ^th punnet 100, such that the cell position 72b has the 4 ^th to 6 ^th punnet group 70. The stopper pairs 40 of cell position 72a will then stop the 1 ^st punnet 100, such that the cell position 72a has the 1 ^st to 3 ^rd punnet group 70. The above operation is performed for each conveyor lane 12 and thus each group 70 has six punnets 100 each. The operation is performed quickly being about 2 to 3 seconds. The above is an example only and the punnets can be grouped into different numbers as desired.

[49] As noted, and shown in Figure 4 to 9, each stopper pair 40 includes a first stopper bar 42 and a second stopper bar 44. The first stopper bar 42 and the second stopper bar 44 are disposed to extend vertically. The first stopper bar 42 has a first distal end portion 42a and the second stopper bar 44 has a second distal end portion 44b, with the distal end portions 42a and 44b having an initial lowered position below the upper surface 17 of the respective conveyor belt 16. The first stopper bar 42 and the second stopper bar 44 are respectively actuatable by respective actuators 46, 47 (e.g. pneumatic type, electric type, etc.) such that the first distal end portion 42a and the second distal end portion 44b extend above the upper surface 17 of the respective conveyor belt 16, which defines a raised position of the first stopper bar 42 and the second stopper bar 44. [50] As is known, a punnet 100 includes a lower well 102 with an upper lid 104 hingedly connected thereto. The lower well 102 includes a peripheral flange 106 being an outward extension thereof which is joined at one edge to the upper lid 104 and having formations at the other edges for closing the lid 104 thereto. The flange 106 thus extends outwardly from the lower well 102. The flanges 106 of adjacent punnets 100 engage each other which provides a space between the lower wells 102 thereof.

[51 ] As shown in Figures 7 and 8, the raised position of the first stopper bar 42 is to a height such that the first distal end portion 42a engages the lower well 102 of the punnet 70 to be held in position, being the lead punnet 100 for each group 70. The first stopper bar 42 of the cell position 72d will firstly engage the 10 ^th punnet 100, the first stopper bar 42 of cell position 72c will then engage the 7 ^th punnet 100, the first stopper bar 42 of cell position 72b will then stop the 4 ^th punnet, and the first stopper bar 42 of cell position 72a will then stop the 1 ^st punnet 100. As noted above, the spacing assemblies 20 are disposed such that the groups 70 are spaced from each other - that is, the lead punnet 100 in each group is spaced from the last punnet in the next group. The above is an example only as the sequence depends on product flow. For example, a line run of 6 punnets only in each conveyor lane 12 will actuate only cell positions 72a and 72b.

[52] Once the lead punnets 100 are held in position by the first stopper bar 42, the second stopper bar 44 is then moved to its raised position (Figure 8) such that the second distal end portion 44b thereof engages the flange 106. The first stopper bar 42 is then lowered back to its initial position (Figure 9) which creates a space 120 between the second stopper bar 44, the lower well 102 and under the flange 106. This allows one of the fork tines 83 to be inserted into the space 120 for engaging the flange 106. As the lower wells 102 of adjacent punnets 100 are spaced via their engaging flanges 106, respective fork tines 83 can be inserted (Figure 12 and 13) between the spaced lower wells 102 for engaging the flanges of the adjacent punnets 100. The fork 81 thus has four fork tines 83 for engaging the three flange to flange engaging punnets 100. The fork tines 83 are also of a width to assist with alignment of the punnets 100 in each group 70.

[53] Guide rails are provided for the conveyor 1 1 for guiding the punnets 100 therealong. The guide rails extend along the side edges of the conveyor 1 1 and between the conveyor lanes 12. The guide rails are disposed to extend above the upper surface 17 of the conveyor belts 16 to engage the flanges 106 to keep the punnets 100 on the conveyor belts 16 and maintain alignment of the punnets 100. Some of the guide rails 200 retract downwardly to a lowered position once the punnet groups 70 are formed such that the guide rails 200 do not impede the fork tines 83. [54] As shown in Figures 3, 10 and 11 , the guide rails includes a distal rail 210 disposed opposite to the fork 81 . The distal rail 210 is stationary and does not have to be retracted as it does not impede the fork tines 83. The guide rails includes central rail 220 between the conveyor lanes 12, and a proximal rail 230 adjacent the fork 81. The central rail 220 is retractable downwardly via a suitable actuator to be below the upper surface 17 of the conveyor belts 16 so as to not be in the way of the fork tines 83. The proximal rail 230 includes a spaced cutouts 232 which provides openings for the fork tines 83. The proximal rail 230 can be raised to provide a solid uninterrupted rail and then lowered as needed to present the cutouts 232 to the fork tines 83.

[55] As shown in Figures 13 to 17, in use, the fork tines 83 are inserted below the flanges 106 to lift the punnets 100 with the fork 81 . The fork 81 then moves the punnets 100 over the conveyor 1 1 towards a series of boxes or trays 300 ready to receive the punnets 100. The fork tines 83 are tilted downwardly and the fork 81 is retracted back by the robotic arm, causing the punnets 100 to be slide into the box/tray as needed.

[56] The assembly additionally includes lid sensors 92 which can detect if any of punnet lids 104 are open. This function can alternatively be performed with a vision system. If there is an open punnet lid detected, then the whole group of punnets is flushed out onto reject shutes 174. Alternatively, only the punnets with the affected group can be flushed. Figures 19 and 20 show hatch doors 172 at the distal end of the conveyor 1 1 . If the punnets are to be rejected, the hatch doors 172 are opened by actuators at which the conveyor 11 can move the punnets to the reject chute 174.

[57] The assembly 10 has three fault conditions at which the punnets are rejected into the reject shuts: (1 ) open lid, (2) rotated punnet by 90° (as the punnets are not square) and (3) count fault or gate not extended fault. The sensors 90 above also act as rotated punnet sensors.

[58] Figure 21 (a) to (f) shows unloading tabs 112 which assist in unloading the punnets 100 from the fork tines 83 towards the boxes or trays 300. The unloading tabs 1 12 are moved up to extend vertically, from below and adjacent the base 82, and between the fork tines 83. When the robotic arm 80 is withdrawn or moves back, the punnets 100 can engage the unloading tabs 112 and ensure unloading from the fork tines 83. The unloading tabs 112 are mounted to a bar 1 10 which is actuatable to move in the vertical direction for moving the unloading tabs 1 12 up and down. The unloading tabs 1 12 are in the lowered position initially by default and are raised only to assist in the unloading. The unloading tabs 112 assist in unloading all the punnets 100 from the forks 83 including any misoriented/rotated punnets 100 which would normally not unload properly. [59] The present invention thus provides an automated assembly for handling and packing punnets into trays/boxes. In application, a product lane diverter diverts the required number of punnets into each individual conveyor lane in preparation for packing into the cases, this being a number of lanes depending on customer requirements. Punnets and boxes can be bidirectionally fed and work simultaneously and independently of each other to situate the punnets and trays in preparation for packing.

[60] The trays are stopped and held in position by a series of pneumatic or electric actuators to be correctly spaced for the robotic tool to pick and place the punnets. Typically the robot tool, depending on the robot weight and size, is able to feed four trays in approximately a four second cycle without damage to the product. When the punnets flow into the robotic pick area they remain on the transfer conveyor through a series of gates. The product is stopped in position by a small cylinder with fingers, once the stop-finger is extended the longer positioning fingers are extended and the stop finger retracts, the positioning fingers line up the product ready for the robot to pick the punnets.

[61 ] Before the robot is able to pick the product, retractable guides with segregated fingers, designed to keep the punnets in position, are retracted which allows the robotic tool access underneath the lip/flange of the punnets to lift the punnets and gently place them into the desired trays.

[62] The machine is designed to insert plastic punnets into cardboard or plastic cases/trays for distribution and transport to supermarkets and markets.

[63] It works by eliminating unnecessary components, machinery and movements. The invention is able to run the punnets at a slower speed than typical as the machine is able to function with the punnets nose to tail or in contact with each other. The benefit of this is less damage to product, slower conveyor speeds (minimizing wear and tear on machinery), reduction of process time and a resulting quicker output.

[64] The robotic tool is custom designed for specific applications but the basic principles remain the same in that it is able to lift punnets by the flange or skirt without applying a mechanical force to grip the punnets or vacuum force to lift the punnet by the lids. This again limits damage to product by punnets popping open as punnets are designed to open the lids by applying a force to the sides of the punnets. In addition to this the tool is custom cut to the size of the punnets and the required number of punnets per tray. The product can be packed into single, double or triple layered cases as necessary for client requirements.

[65] The robotic cell is able to be configured to simultaneously accept two different tray configurations and product / punnet sizes. Because the punnets remain on the in-feed conveyor the machine is able to do a series of checks through vision camera or sensors to detect open lids, rotated punnets, a faulty gate I stopper or faulty counters. If any of these faults are detected the machine will automatically flush the punnets outside of the pick area and start the cycle again without the need for human intervention, resulting in increased speed and efficiency.

[66] Overall the aim of the invention is to reduce human labour requirements and costs, increase efficiency within the packhouse and reduce human injury namely repetitive strain injuries.

[67] The assembly can also be used for moving punnets from one conveyor to another if needed.