GB2378172A

GB2378172A - Gripper in or for a robot

Info

Publication number: GB2378172A
Application number: GB0116225A
Authority: GB
Inventors: David Ian Haith
Original assignee: Tickhill Engineering Co Ltd
Current assignee: Tickhill Engineering Co Ltd
Priority date: 2001-06-02
Filing date: 2001-07-03
Publication date: 2003-02-05
Also published as: GB0116225D0; GB0113402D0

Abstract

A gripper 10 in or for a robot wherein said gripper comprises a body, adapted to be, or mounted on, said robot, the body having first and second article engageable means 23 and a vacuum nozzle 41 and valve means to control the vacuum. Preferably, the gripper parts 23 have hook-like formations to grip a corresponding fitting on eg. a tray or basket (21, fig 1). Preferably the hook parts and suction cup(s) are used alternatively. There can be a plurality of suction cups provided with ones acting on the top of the article to be picked up and one on the side (59, Fig 6). An additional pallet engaging fitting eg. forks (73, Fig 7) can also be provided.

Description

PATENTS ACT 1977 A10361GB-JNL Title: Gripper in or for a Robot Description of Invention This invention relates to a gripper in or for a robot of the kind, hereinafter referred to as being of the kind described, having a base, an arm movable relative to the base in a predetermined manner and the arm having, or being adapted to have, mounted thereon said gripper.

It is desirable to use a robot for a plurality of applications. For example, to move different containers such as bags, boxes and trays such as trays of the kind known as"supermarket trays". Typically, but not exclusively, a product such as carrots or potatoes is transported in such containers. The transporting operation usually includes a pick up operation so that the containers may be stacked, for example, on pallets.

Hitherto it has been necessary to use a different robot for each such container.

An object of the invention is to provide a new or improved gripper in or for a robot of the kind described whereby the abovementioned disadvantage is overcome or is reduced.

According to one aspect of the invention we provide a gripper in or for a robot of the kind described wherein said gripper comprises a body, adapted to be, or mounted on, said robot, the body having first and second article engageable means and a vacuum nozzle and valve means to control the vacuum.

The article engageable means may be operable alternatively to the valve means.

Each of the first and second article engageable means may comprise a hook assembly movable between an extended position in which the hook assembly is positioned for engagement with a formation of the article and a

retracted position in which the hook assembly is positioned to be disengaged from the formation of the article.

Each hook assembly may be moved between said retracted and extended positions by a fluid operated ram such as a pneumatic ram.

Each hook assembly may be pivotally mounted on the body.

Each hook assembly may comprise a pair of laterally spaced hooks.

The formation may comprise a spigot on the article.

The spigot for engagement by a hook assembly may be provided by a rod extending across the article.

The article may comprise a tray.

The body may be adapted to receive an attachment for engagement with a second article, such as a bag or a box wherein suction applied through the nozzle holds the bag or box onto the gripper.

A different attachment may be used for a bag to that used for a box.

The attachment for a bag may comprise a single tubular formation which is flexible at least at one end for engagement with a bag.

The tubular formation may comprise a bellows.

The tubular formation, at said one end, may have an open mouth which faces downwardly to engage the top of the bag.

The attachment for a box may comprise at least two tubular formations orthoganally disposed and each being flexible at least at one end for engagement with the box.

Each tubular formation may comprise a bellows.

One of the tubular formations, at said one end, may have an open mouth which faces downwardly to engage the top of a box and the other of the tubular formations may have, at said one end, an open mouth which faces sideways to engage a side of the box.

The gripper may be adapted to be engaged with an attachment whereby a robot may manipulate a pallet.

The attachment may include a pair of fork tines.

The gripper may be adapted to engage with the pallet manipulating attachment by engagement of a projection on one of said gripper and pallet manipulating attachment in a recess provided on the other of said gripper and pallet manipulating attachment.

The projection may be provided on the gripper and the recess may be provided on the pallet manipulating attachment.

Two sets of inter-engaging projections and recesses may be provided.

The pallet lifting manipulating attachment may comprise a pair of spaced limbs, adapted to receive the gripper therebetween, connected at one end to one end of a pair of tines.

The projections or recesses may be on said limbs.

An example of the invention will now be now be described with reference to the accompanying drawings wherein :- Figure 1 is a diagrammatic side view of a gripper embodying the invention, Figure 2 is a plan view of the gripper shown in Figure 1, Figure 3 is a side view showing the gripper of Figures 1 and 2 adapted for use with a different article, Figure 4 shows the gripper of Figure 3 attached to a bag, Figure 5 is a side view of the gripper of Figures 1 and 2 shown adapted for use with a further different article, and Figure 6 is an end view of the gripper of Figure 5 shown attached to a box.

Referring now to the drawings, a gripper is indicated generally at 10 and is connected to an end part 11 of an arm of a robot of conventional kind. In the example illustrated the end part 11 is mounted for rotation about an axis X-X and for pivotal movement about a horizontal axis at one end of an arm which is connected through other links via pivotal connections to a base turntable which

is rotatable about a vertical axis. All the parts of the robot are movable by suitable means under control of a computer and the computer can be programmed to cause the arm to perform a predetermined series of operations.

The gripper 10 is connected to the part 11 of the arm via an intermediate tubular part 12 which is bolted to the part 11 by means of co-operating flanges 13 which are bolted together as indicated at 14.

The gripper 10, as best shown in Figure 2, has a body 15 of rectangular configuration in plan view and of generally inverted channel shape in end elevation as can be seen from Figures 1 and 6. Thus the body 15 has a top generally horizontal part 16 connected to the intermediate part 12 and a pair of downwardly extending side walls 17, the undersides of which are provided with a generally central cut-out part 18 and a pair of slots 19 which are adapted to receive spigots 20 of a tray 21 of conventional rectangular in plan view configuration. The spigots 20 extend inwardly from an upper wall part 22 of the flanges which extend along the longer sides of rectangle and are preferably provided in pairs by a bar which extends across the tray.

Each wall 17 also has pivotally carried thereon first and second hook elements 23 so that each is pivotable about a horizontal axis 24 by means of a pneumatically operated ram 25 which is pivotally connected to a hook element 23 at 26 whilst the cylinder thereof is pivotally connected to lugs 27 of the body 15 as indicated at 28.

In use, when it is desired to pick up a tray the robot is manipulated so as to be positioned above the tray and the pistons and associated rods 29 of the ram 25 are retracted to retract the hook elements 23. After the robot has been lowered so that the spigots 20 are engaged in the slots 19. The rams 25 are actuated to move the hooks 23 from their retracted position to their extended position so as to engage the spigots 20 whereby the tray may be lifted and transported to a desired location by the robot. 9

Each hook has a sensor associated therewith so as to check that it has engaged with the bar and only then is the robot allowed to lift the tray.

The gripper 10 is also provided with a central tubular part 30, the interior of which is in communication with a conduit 31 which is connected via a valve 32 and a flexible hose 33 to a source of pressure which is below atmospheric pressure, herein referred to as a vacuum, which may conveniently be mounted adjacent a base of the robot. The conduit 31 is also provided with a valve 34 and a filter 35 to enable the vacuum to be released by connecting the conduit 31 to atmosphere.

When it is desired to adapted the gripper to pick up flexible bags a bellows-like device is attached to the underside of the tubular part 30 as shown in Figure 3 at 40. The bellows 40 has an end part 41 and is adapted to maintain a generally circular shape in cross-section.

When it is desired to pick up a bag the robot is manipulated to a position above the bag and the vacuum is switched on to the interior of the bellows 40 so that the end 41 thereof engages the bag 42 and the suction applied by the vacuum within the bellows 40 causes the bellows to be attached to the bag 42 whereupon the robot can be manipulated to a desired position.

When it is desired to move a rigid box the gripper is provided with a plenum chamber 50 of generally L configuration comprising a generally horizontal limb 51 and a generally vertical limb 52. The limb 51 has an adaptor 53 whereby it may be fastened to the underside of the vertical part 30 and in addition carries two generally rectangular bellows-like components 54,55 one of which has a downwardly facing generally flexible open mouth 56 at one end for engagement with an upper surface 57 of a box 58. The downwardly extending limb 52 of the plenum chamber has a generally rectangular part 59 having at one end 60 a flexible component for engaging with a side surface 61 of the box 58.

When it is desired to engage the gripper with such a box the vacuum is again applied and the robot is manipulated to bring the open mouths 56 and 60 into engagement with the surfaces 57 and 61 so that the suction created by the vacuum attaches the box 58 to the gripper whereupon the robot can be manipulated to move the box to a desired position.

The gripper may be adapted to be engaged with an attachment which enables the robot to manipulate the pallet. For example, the device or attachment may comprise a pair of fork tines. The fork tines may be engageable with a pallet such as a pallet on a stack of empty pallets whereby the robot may position the pallet in a position ready for the robot to start stacking the pallets again.

Referring now to Figure 7, the gripper 10 is also provided with bosses 70 or other projections on the downwardly extending side walls 17 which are adapted to be received in co-operating recesses 71 provide in a pair of limbs which are spaced apart so as to extend alongside the side walls 17. One of these limbs is shown at 72 in Figure 7. The limbs 72 are part of a pallet lifting attachment indicated generally at 73 which comprises a pair of spaced parallel tines 74 similar to the tines of a fork lift truck and which are connected to the limbs 72 by a vertical member or members 75 of any desired configuration.

When it is desired to engage a body such as a pallet with the gripper 10 the pallet lifting attachment 73 is engaged with a multi-function gripper 10 by disposition of the bosses 70 or other projections in the sockets 71 and then the robot is manipulated so as to position the tines in lifting engagement with the pallet. In other respects the gripper 10 is as described hereinbefore. If desired the bosses or other projections may be provided on the limbs 72 and the recess provided on the gripper 17.

In the present specification"comprise"means"includes or consists of" and"comprising"means"including or consisting of.

The features disclosed in the foregoing description, or the following claims, or the accompanying drawings, expressed in their specific forms or in terms of a means for performing the disclosed function, or a method or process for attaining the disclosed result, as appropriate, may, separately, or in any combination of such features, be utilised for realising the invention in diverse forms thereof.

Claims

1. A gripper in or for a robot of the kind described wherein said gripper comprises a body, adapted to be, or mounted on, said robot, the body having first and second article engageable means and a vacuum nozzle and valve means to control the vacuum.

2. A gripper according to Claim 1 wherein the article engageable means is operable alternatively to the valve means.

3. A gripper according to Claim 1 or 2 wherein each of the first and second article engageable means comprises a hook assembly movable between an extended position in which the hook assembly is positioned for engagement with a formation of the article and a retracted position in which the hook assembly is positioned to be disengaged from the formation of the article.

4. A gripper according to Claim 3 wherein each hook assembly is moved between said retracted and extended positions by a fluid operated ram, such as a pneumatic ram.

5. A gripper according to Claims 3 or 4 where each hook assembly is pivotally mounted on the body.

6. A gripper according to any one of Claims 3 to 5 wherein each hook assembly comprises a pair of laterally spaced hooks.

7. A gripper according to any one of Claims 3 to 6 wherein the formation comprises a spigot on the article.

8. A gripper according to Claim 7 wherein the spigot for engagement by a hook assembly is provided by a rod extending across the article.

9. A gripper according to any one of the preceding claims wherein the article comprises a tray.

10. A gripper according to any one of the preceding claims wherein the body is adapted to receive an attachment for engagement with a second article, such as a bag or a box wherein suction applied through the nozzle holds the bag or box onto the gripper.

11. A gripper according to Claim 10 wherein a different attachment is used for a bag to that used for a box.

12. A gripper according to Claim 10 or 11 wherein the attachment for a bag comprises a single tubular formation which is flexible at least at one end for engagement with a bag.

13. A gripper according to Claim 12 wherein the tubular formation comprises a bellows.

14. A gripper according to Claim 12 or 13 wherein the tubular formation, at said one end, has an open mouth which faces downwardly to engage the top of the bag.

15. A gripper according to any one of Claims 10 to 14 wherein the attachment for a box comprises at least two tubular formations orthoganally disposed and each being flexible at least at one end for engagement with the box.

16. A gripper according to Claim 15 wherein each tubular formation comprises a bellows.

17. A gripper according to Claim 15 or 16 wherein one of the tubular formations, at said one end, has an open mouth which faces downwardly to engage the top of a box and the other of the tubular formations may have, at said one end, an open mouth which faces sideways to engage a side of the box.

18. A gripper according to any one the preceding claims wherein the gripper is adapted to be engaged with an attachment whereby a robot may manipulate a pallet.

19. A gripper according to Claim 18 wherein the attachment includes a pair of fork tines.

20. A gripper according to Claim 18 or Claim 19 wherein the gripper is adapted to engage with a pallet manipulating attachment by engagement of a projection on one of said gripper and pallet manipulating attachment in a recess provided on the other of said gripper and pallet manipulating attachment.

21. A gripper according to Claim 20 wherein the projection is provided on the gripper and the recess is provided on the pallet manipulating attachment.

22. A gripper according to Claim 20 or Claim 21 wherein two sets of intert : l engaging projections recesses are provided.

23. A gripper according to any one of Claims 18 to 22 wherein the pallet manipulating attachment comprises a pair of spaced limbs, adapted to receive the gripper therebetween, connected at one end to one end of a pair of tines.

24. A gripper according to Claim 23 wherein the projections or recesses are provided on said limbs.

25. A gripper substantially as hereinbefore described with reference to the accompanying drawings.

26. Any novel feature or novel combination of features described herein and/or in the accompanying drawings.