WO2021224304A1

WO2021224304A1 - Vacuum suction apparatus

Info

Publication number: WO2021224304A1
Application number: PCT/EP2021/061802
Authority: WO
Inventors: Peter Newman
Original assignee: Brillopak Limited
Priority date: 2020-05-05
Filing date: 2021-05-05
Publication date: 2021-11-11
Also published as: EP4146443A1; GB202013937D0; GB2594758A; GB2594758B; GB202006660D0

Abstract

A vacuum suction gripper head for robotic apparatus which includes a plurality of vacuum cups (24) each operable to transfer objects from a moving conveyor to is produced from a relatively light weight material and is internally formed with a plurality of discrete passageways (14) each of which is connected at one end to receive gas under pressure from a source remote from the gripper head and to discharge said gas through an opening (22) remote from said one end. At least one vacuum generator cartridge (16) located within each said passageway (14) in the path of said gas under pressure, and which is operable to generate within the respective vacuum cup (24) a vacuum for enabling the transfer of objects from a conveyor to a container positioned alongside said container.

Description

VACUUM SUCTION APPARATUS

Field of the Invention

This invention relates to vacuum suction apparatus for transferring items from one location to another.

Background to the invention

The invention has particular application to end-of-line packing and palletising of various items of packaged and unpackaged food and other objects from a relatively high-speed conveyor to a holding container positioned alongside the conveyor. Within the food sector, robotic devices for transferring selected items from high speed conveyers to plastics retail crates or trays are commonly employed.

Previously, robotic apparatus (often referred to as end effectors) which include one or more mild or stainless steel or plastics suction gripper heads has been employed to select and place a limited number of items of food or other objects from a high speed conveyor into or onto a succession of stationary relatively small containers each of which is able to receive only a limited number of items.

Efficient operation of such apparatus requires accurate placement of items on or within a selected container. Additionally, in order to maximise load logistical efficiency, the items need to be placed as close as possible to the sides of the container and to each other. Furthermore, particularly for perishable and easily damaged items, it is important that the items be located in a selected container in a consistent and attractive format.

There is also an ongoing requirement that the transfer of the items from the conveyor to the container be conducted at high speed to maximise efficiency.

An additional problem to be overcome is that products to be loaded are sometimes themselves packed into bags using processes such as flow wrap, heat seal and vertical fill seal. This often leads to a relatively unstable product which requires careful management.

As already mentioned, robotic apparatus for automatically moving objects from, for example, a moving belt conveyor to a storage container using metallic vacuum suction gripper heads is well known. However, the presence of relatively heavy metallic gripper heads places a limitation on the operational speed of the apparatus and the ability of the gripper heads to place items accurately within or on a receiving crate or tray. Additionally, such known robotic apparatus generally comprise four or more vacuum suction grippers carried by a single gripper head, each suction gripper being connected individually through a plurality of external flexible pipes located on an exposed surface of gripper head to a source of pressurised fluid, and to the atmosphere for discharge purposes.

The presence of these multiple pipes on the gripper head further inhibits the ability of the head to move swiftly and safely between desired packaging locations and often leads to disruptions in the movement of objects and potential damage to the apparatus.

Typically, vacuum suction gripper heads have, as mentioned previously, been produced from mild or stainless steel, or a plastics material, and one important challenge to date has been to achieve high product handling speeds of products using relatively heavy gripper heads and products whose combined weight can often exceed in excess of 2.5kg.

In this context, mild or stainless steel gripper heads are both overly large, heavy and cumbersome to operate at the required high speeds and to achieve the required accurate placement of products within receiving containers. Plastics gripper heads, while lighter, have in practise been unable to achieve consistency of product pick at the required high speeds.

The present invention sets out to provide vacuum suction apparatus with relatively light weight and durable gripper heads with no or limited external piping which overcomes or at least alleviates the aforementioned and other problems encountered with currently available vacuum suction apparatus.

Summary of the Invention

In one aspect the invention provides a vacuum suction gripper head for robotic apparatus which includes a plurality of vacuum cups each operable to transfer objects from a moving conveyor to a container positioned alongside said conveyor, said gripper head being produced from a relatively light weight material and being internally formed with a plurality of passageways each of which is connected at one end to receive gas under pressure from a source remote from the gripper head and to discharge said gas through an opening remote from said one end, and at least one vacuum generator cartridge located within each passageway in the path of said gas under pressure, said vacuum generator cartridge being operable to generate within the respective vacuum cup a vacuum for enabling the transfer of objects from a moving conveyor to a container positioned alongside said conveyor.

Preferably, the suction gripper assembly is produced by a 3D printing of a relatively light weight material. Preferably, the apparatus comprises four cartridges each located within a respective channel extending from a top surface of the head downwardly into the gripper head.

Preferably, the apparatus comprises a fifth cartridge locatable in a channel extending from and into one side of the gripper head.

Preferably, the gripper head includes an air channel inlet leading to a fluid channel extending into the head and ending in a dividing junction to provide separate channels connected at one end to a respective cartridge.

Preferably, the head further includes an internal chamber having an aperture to provide a fluid communication with vacuum suction cups.

Preferably, the dividing junction also provides a separate channel connected at one end to the internal chamber.

Preferably, the side channel is connected at one end to the internal chamber for the fifth cartridge to be locatable therein.

In another aspect, the invention provides a vacuum suction gripper head for robotic apparatus which includes a plurality of suction cups produced by 3D printing of a relatively light material, said gripper head being formed during 3D printing with a plurality of internal passageways each connectable at one end to a source of gas under pressure and to discharge said gas through an opening remote from the said one end, and at least one vacuum generator cartridge located within each passageway at said remote opening in the path of the flow of gas under pressure, each said vacuum generator cartridge being operable to generate within the respective vacuum cup a vacuum for enabling the transfer of objects from a moving conveyor to a container positioned alongside the conveyor.

Brief description of the drawings

The invention will now be described by way of example only with reference to the accompanying diagrammatic drawings, in which

Figure 1 is an exploded view of a vacuum suction gripper assembly in accordance with the invention;

Figure 2 is a view from above of the assembly shown in Figure 1 ;

Figures 3 and 4 are respectively front and side views of the assembly shown in Figures 1 and 2; Figure 5 is a perspective view of the illustrated vacuum suction gripper assembly;

Figure 6 is a plan view from below of the illustrated vacuum suction gripper assembly;

Figure 7 is a cross section side view of the vacuum suction gripper assembly;

Figure 8 is a perspective view of the gripper assembly in cross section;

Figure 9 is a perspective view of an alternative embodiment of a vacuum suction gripper assembly in accordance with the invention; and

Figure 10 is an exploded view of the assembly of figure 9.

Detailed description of a preferred embodiment of the invention

The vacuum suction gripper assembly illustrated in the drawings is produced by a 3D printing from a polymeric or similar material and comprises a gripper head block 10 formed in its upper surface with an inlet chamber 12 connected to receive air under pressure from an external source.

Producing the assembly by 3D printing uniquely enables the assembly to be accurately produced as a single item from a relatively light weight material with all required airflow passageways other than that required to connect the assembly to a source of air under pressure formed internally within the assembly.

As will be seen from the drawings, the inlet chamber 12 directs the pressurised air received from the source into and through five internal and separate passages 14, four being located as shown in the upper surface of the gripper head block and one in one side of the block. Positioned towards the end of each passage 14 remote from the inlet chamber 12 is a pair of side-by-side micro vacuum cartridges 16. Each cartridge is formed with a threaded end 18 and each pair of cartridges is secured to an internally threaded holder 20 which is, in turn, secured to the gripper head block 10.

Each vacuum cartridge is formed with a venturi shaped conduit to cause air passing through the cartridge to accelerate.

The gripper head block is formed with a series of spaced internal passages (shown in figure 7) which place the inlet chamber 12 in communication with one of five discharge ports 22 located at the discharge end of each of the five internal passages 14 of the gripper head block.

Each pair of vacuum cartridges 16 communicates directly via or through an internal passageway of the gripper head block with the five vacuum cup assemblies 24 positioned as an array depending from the underside of the gripper header block 10. Thus, each vacuum cup assembly is placed in communication with one of the internal passages formed in the gripper head and one pair of vacuum cartridges 16.

A filter unit 26 is positioned within the entrance to each vacuum cup assembly.

In operation of the illustrated assembly, as the pressurised air passes over and/or through each pair of vacuum generating cartridges, it accelerates to draw air rapidly through each of the five vacuum cup assemblies thereby generating within each of the five vacuum cup assemblies 24 when placed in contact with a product or package to be relocated, a vacuum which enables the selected package to be lifted from the conveyor to a container or tray located alongside the conveyor. Thus, each vacuum cup assembly acts as a micro vacuum generator.

Pressurised air is discharged from the gripper assembly through the discharge ports 22.

Positioned within each internal passage of the gripper block head 10 is a 3D silencer. The presence of these silencers is to increase the efficiency of the compressed air and also to provide an increase in consistency of suction at each vacuum generating assembly thereby ensuring that more products can be transported by the gripper head and for these products to be positioned more accurately within a crate or on a tray.

Figures 7 and 8 are cross section views of the gripper assembly showing in detail the discrete internal air passageways that produce the suction affect.

As can be seen from the figures, the inlet chamber 12 leads to a first passageway 30 extending downwardly, in a substantially vertical orientation, through the head block 10. The bottom end of the passageway 30 leads to a dividing junction 32 which splits the air passageway into several discrete channels. Four channels 34A-D, formed as elongate tubes, extend and connect to the base of each respective vacuum cartridge 16. Another channel 36 extends and connects to the end of an internal chamber 38 housed within the body of the gripper head 10.

The vacuum cup assembly is in fluid communication with the base of the chamber 38 through an aperture 40 in the base of the chamber 38 to lift and lower the vacuum cup assembly as a vacuum is applied to the chamber causing the suction effect.

A further cartridge 16 extends into the passageway extended into the side of the head 10 to predominantly locate within the chamber 38.

Advantages of the vacuum suction gripper assemblies include the following. The unique internal air flow passages provide a gripper assembly having a relatively small footprint and enhanced accuracy of placement of products in the collection containers or trays with no contact with these containers or trays thereby preventing impact damage to the vacuum suction gripper assembly thereby reducing machine downtime and increasing productivity.

By dispensing with the external pipework to be found with existing machines, the maintenance and cleaning of the apparatus is significantly simpler and faster resulting in enhanced efficiency changeovers between products.

Furthermore, by employing multiple vacuum generators the gripper assemblies are able to operate efficiently even if one or more vacuum cups fails to connect with a product when handling products of varying shape. This has the dual effect of ensuring that the compressed air is shared amongst a multiplicity of suction cups to ensure no damage to products while simultaneously ensuring that, regardless of the number of cups connected to the product, the force of the vacuum will be sufficient to pick up the product without marking.

Figures 9 and 10 illustrate an alternative embodiment. The assembly here is generally of the same construction as the first embodiment described above works on the same principles. In this embodiment though a single two-stage micro vacuum cartridges 42 extend into each passageway 44 in the gripper head block 46. Air diffusers 48 are located over the end of each cartridge 42.

This embodiment is more compact making it easier to fit into the packing machine.

The size and power of the assembly may be further increased by including three-stage cartridges and providing an adapter to between the robot fixing 50 and the gripper head block 46.

It will be appreciated that the foregoing is merely exemplary of vacuum suction apparatus in accordance with the invention and that modifications thereto can readily be made without departing from the invention as set out in the appended claims.

Claims

1. A vacuum suction gripper head for robotic apparatus which includes a plurality of vacuum cups each operable to transfer objects from a moving conveyor to a container positioned alongside said conveyor, said gripper head being produced from a relatively light weight material and being internally formed with a plurality of discrete passageways each of which is connected at one end to receive gas under pressure from a source remote from the gripper head and to discharge said gas through an opening remote from said one end, and at least one vacuum generator cartridge located within each said passageway in the path of said gas under pressure, said vacuum generator being operable to generate within the respective vacuum cup a vacuum for enabling the transfer of objects from a conveyor to a container positioned alongside said container.

2. A gripper head according to claim 1 , comprising four cartridges each located within a respective channel extending from a top surface of the head downwardly into the gripper head.

3. A gripper head according to claim 2, further comprising a fifth cartridge locatable in a channel extending from and into one side of the gripper head.

4. A gripper head according to any one of claims 1 to 3, wherein the gripper head includes an air channel inlet leading to a fluid channel extending into the head and ending in a dividing junction to provide separate channels connected at one end to a respective cartridge.

5. A gripper head according to claim 4, wherein the head further includes an internal chamber having an aperture to provide a fluid communication with vacuum suction cups.

6. A gripper head according to claim 4, wherein the dividing junction also provides a separate channel connected at one end to the internal chamber.

7. A gripper head according to claim 6, wherein the side channel is connected at one end to the internal chamber for the fifth cartridge to be locatable therein.

8. A gripper head according to any preceding claim, produced by 3D printing.