Field

[0001] This invention primarily relates to a gripping device. In particular, a gripping device for disengaging and re-engaging a stopper from a hole.

Background

[0002] It is common for containers storing fluids or the like to have an access hole to fill the container with fluid, sample and/or inspect the fluid in the container, or drain the container of its contents. The access hole is usually plugged by means of a stopper, which may be held in place by a variety of means, including threads, bayonet fittings, friction or the like. In some commercial environments, such as the wine industry, the stopper must be frequently removed to allow inspection of the fluids within the container to monitor the progress of manufacturing processes taking place in the container, or assess quality of a product container in the container. In the wine industry the container may be a maturation vessel constructed from wood, stainless steel or other suitable materials.

[0003] Disengaging a stopper from the access hole can be an arduous and dangerous task. The task is difficult to complete with traditional tools, since access to the stopper is restricted from like wine barrels being stored above and around the wine barrel to be inspected. Therefore, at present, the stopper is disengaged and removed from the hole manually. This presents dangers to the worker disengaging the stopper, as their knuckles might scrape against the like wine barrel sitting immediately above the wine barrel to be inspected. Further, the large numbers of wine barrels to be inspected make disengaging and removing a stopper a tedious and repetitive process. The workers performing the process are increasingly likely to commit errors that may have material or personal damage consequences.

[0004] Additionally, when a fermentation or maturation process goes awry, it may be the case that the contents of the fermentation vessel are at a different pressure than the surrounding environment. The pressure differential can cause the stopper removal process to become even more dangerous or physically demanding. [0005] Re-engaging the stopper faces similar difficulties, although the danger of pressurised liquid is not present.

[0006] It would be desirable to provide a tool capable of disengaging, removing, replacing and/or re-engaging the stopper from the hole to enable the inspection of more wine barrels, or inspect the wine barrel more frequently.

Object of the Invention

[0007] It is an object of the present invention to substantially fulfill the above desire, or at least provide a useful alternative to the above described manual approach.

Summary of Invention

[0008] In a first aspect the present invention provides a gripping device for engaging and/or disengaging a stopper in a hole, the gripping device including:

a base plate having a central axis, the central axis being normal to the base plate;

a gripper guide located adjacent the base plate; and

a set of grippers located on the base plate such that the grippers and the gripper guide are movable relative to each other about the central axis;

wherein the gripper guide, the grippers and the base plate are configured such that relative movement between the gripper guide and grippers moves the grippers toward the central axis to grip the stopper, and subsequent turning of the grippers about the central axis at least aids in releasing the stopper with respect to the hole,

wherein the relative movement is caused by a motor assembly.

[0009] Preferably, the base plate is movable about the central axis such that turning of the base plate turns the gripper guide and the grippers.

[0010] Preferably, each gripper is connected to the gripper guide by means of a protrusion engaged with a drive recess.

[001 1] Preferably, the protrusion is a drive pin engaged with the drive recess, and the drive recess is located in the gripper guide. [0012] Preferably, the drive recess is arcuate.

[0013] Preferably, the drive recess is linear.

[0014] Preferably, each gripper is located in a slot in the base plate for preventing the grippers from turning about the central axis relative to the base plate.

[0015] Preferably, the motor assembly includes a first actuator adapted to turn the base plate.

[0016] Preferably, the first actuator is coupled to the base plate with a first gear transmission.

[0017] Preferably, the first gear transmission is integrally formed with the base plate.

[0018] Preferably, the first actuator is coupled to the base plate with a belt drive.

[0019] Preferably, the motor assembly includes a second actuator adapted to turn the gripper guide.

[0020] Preferably, the second actuator is coupled to the gripper guide with a second gear transmission.

[0021] Preferably, the second gear transmission is integrally formed with the gripper guide.

[0022] Preferably, the second actuator is mounted on a retainer plate that is coupled to the base plate.

[0023] Preferably, the gripper guide is located between the retainer plate and the base plate.

[0024] Preferably, the grippers each have a surface facing the central axis and the surface is shaped to be congruent to the outer surface of the stopper.

[0025] Preferably, the grippers are knurled for an improved grip with the stopper.

[0026] Preferably, the grippers include a cap facing the central axis, the cap having a higher coefficient of static friction than the grippers. [0027] Preferably, the base plate is mounted to an adapter plate, the adapter plate being adapted to attach the gripping device to a robot arm.

[0028] Preferably, the base plate has a first hole and the gripper guide has a second hole, the first and second hole being aligned on the central axis and adapted to receive the stopper.

[0029] Preferably, the first and second hole are each circular.

[0030] Preferably, the gripping device further includes locating means to locate the gripping device such that the stopper is received in the first and second hole.

[0031] In a second aspect, the present invention provides a method of disengaging and/or engaging a stopper in a hole, the method comprising the steps of:

(i) locating a base plate having a central axis, the central axis being normal to the base plate, such that the central axis is co-axial with the stopper;

(ii) turning, using a motor assembly, a gripper guide that is located on the base plate, such that a plurality of grippers that are located on the base plate move toward the central axis and grip the stopper;

(iii) turning, using the motor assembly, the grippers, such that the stopper disengages or engages in the hole.

[0032] Preferably, the turning of the grippers in step (iii) is caused by turning of the base plate about the central axis, such that turning of the base plate turns the gripper guide and the grippers.

[0033] Preferably, each gripper is connected to the gripper guide by means of a protrusion engaged with a drive recess.

[0034] Preferably, the protrusion is a drive pin engaged with the drive recess, the drive recess is located in the gripper guide.

[0035] Preferably, the drive recess is arcuate.

[0036] Preferably, the drive recess is linear [0037] Preferably, each gripper is located in a slot in the base plate for preventing the grippers from turning about the central axis relative to the base plate.

[0038] Preferably, the motor assembly includes a first actuator and turning of the base plate is caused by the first actuator.

[0039] Preferably, the first actuator is coupled to the base plate with a first gear transmission.

[0040] Preferably, the first gear transmission is integrally formed with the base plate.

[0041] Preferably, the first actuator is coupled to the base plate with a belt drive.

[0042] Preferably, the motor assembly includes a second actuator and turning of the gripper guide is caused by the second actuator.

[0043] Preferably, the second actuator is coupled to the gripper guide with a second gear transmission.

[0044] Preferably, the second gear transmission is integrally formed with the gripper guide.

[0045] Preferably, the second actuator is mounted on a retainer plate that is coupled to the base plate.

[0046] Preferably, the gripper guide is located between the retainer plate and the base plate.

[0047] Preferably, the grippers each have a surface facing the central axis and the surface is shaped to be congruent to the outer surface of the stopper.

[0048] Preferably, the grippers are knurled for an improved grip with the stopper.

[0049] Preferably, the grippers include a cap facing the central axis, the cap having a higher coefficient of static friction than the grippers.

[0050] Preferably, the method further includes the step of:

(iv) moving the base plate away from the hole, or toward the hole, for disengaging and engaging the stopper in the hole, respectively. [0051 ] Preferably, the base plate is mounted to an adapter plate, the adapter plate being adapted to attach the gripping device to a robot arm.

[0052] Preferably, the base plate has a first hole and the gripper guide has a second hole, the first and second hole being aligned on the central axis and adapted to receive the stopper.

[0053] Preferably, the first and second hole are each circular.

[0054] Preferably, the stopper is a bung and the hole is an access hole in a barrel for containing alcoholic beverages.

Brief Description of Drawings

[0055] Preferred embodiments of the present invention will now be described, by way of examples only, with reference to the accompanying drawings:

[0056] Figure 1 is a perspective view of an embodiment of the gripping device according to the invention.

[0057] Figure 2 is a top detail perspective view of the gripping device of Figure 1.

[0058] Figure 3 is a bottom detail perspective view of the gripping device of Figure 1.

[0059] Figure 4 is a detailed top perspective view of the gripping device of Figure 1 with some components removed.

[0060] Figure 5 is a top view of the gripping device of Figure 1.

[0061] Figure 6 is an exploded perspective detail view of another embodiment of the gripping device according to the invention.

[0062] Figure 7 is a top detail view of the gripping device of Figure 6.

Description of Embodiments [0063] Shown in Figure 1 is an embodiment of a gripping device 10 according to the invention. The gripping device includes an adapter plate 20 and a substantially flat base plate 30, the base plate having an axis 31 at the centre of a hole 35 in the base plate. The adapter plate has a corresponding hole 24 that is also aligned with the axis 31. The base plate 30 is connected to a first motor 40 with a drive belt (not shown), as best seen in Figure 8. In this embodiment the first motor 40 is an electric servo motor and has a pulley 42. The base plate has a belt recess 33 within which the drive belt is located. The base plate 30 is mounted on the adapter plate 20 using bearings 32.

[0064] As best seen in Figure 4, the base plate 30 has six slots 34, each slot 34 having a first channel 36. The base plate 30 also has a second channel 37 for each slot 34. As shown in Figure 3, a gripper 50 is located in each slot 34, each gripper 50 having a cross-sectional profile that substantially corresponds to the cross-sectional profile of the respective slot 34. Each gripper 50 has a drive pin 52 that is engaged with the first channel 36 and second channel 37 of the respective slot 34.

[0065] As best seen in Figure 2, a gripper guide 60 is located on the base plate 30. The gripper guide 60 is mounted on the base plate 30 such that it is tumable relative to the base plate 30, for example by means of a roller bearing (not shown) or a Polytetrafluoroethylene (PTFE) bearing surface (not shown). The gripper guide 60 has six drive recesses 62. The drive pins 52 of the grippers 50 engage the drive recesses 62. The drive recesses 62 are rotationally symmetrically arcuate such that each drive recess defines a path between a first position 64a and a second position 64b. The second position 64b is closer to the axis 31.

[0066] As shown in Figure 4, the gripper guide 60 has a drive gear 66 that cooperates with a second motor gear 46 mounted on a second motor 44. The drive gear 66 is integrally formed with the gripper guide 60. As shown in Figure 1, the second motor is an electric servo motor 44 that is mounted on a retainer plate 70 that is affixed to the base plate 30 using standoffs 72.

[0067] As shown in Figure 5, the adapter plate 20 has two tensioning slots 22. Two tensioning bolts (not shown) are mounted in the tensioning slots 22 for tensioning the drive belt.

[0068] Shown in Figure 6 is a second embodiment of a gripping device 10 according to the invention. Shown here in exploded view, like numerals designate like components to the first embodiment. The embodiment primarily differs from the embodiment shown in Figure 1-5 in that the base plate 30 includes a gear 138 that cooperates with a first motor gear (not shown) mounted on the first motor 40. The gear 138 is integrally formed with the base plate 30.

[0069] Both the first motor 40 and the second motor 44 are controlled by a motor controller (not shown).

[0070] The use of the gripping device 10 will now be described.

[0071] When used to disengage and remove a stopper from a hole, the gripping device 10 is preferably mounted to a manual, hydraulic or robotic arm (not shown) or the like using the adapter plate 20. The gripping device 10 is positioned such that the hole 24, 35, and thereby the axis 31 , aligns with a stopper (not shown) that is engaged in a hole (not shown). The gripping device 10 could include connecting means (not shown) to operatively connect the gripping device 10, mechanically, electronically, optically or the like, with a robotic system.

[0072] The second motor 44 is then engaged, driving motor gear 46 which drives the drive gear 66. The gripper guide 60 is thereby turned. As the gripper guide 60 turns, the grippers 50 are urged toward the axis 31 by the drive pins 52 engaged with the drive recesses 62. The motion of the grippers 50 is kept in a straight line toward axis 31 by the slots 34, wherein the grippers 50 are located, as well as the first and second channels 36, 37 located in the slots 34, wherein the drive pins 52 are engaged.

[0073] As the grippers 50 travel toward axis 31 , they contact, and establish a frictional grip with, the stopper engaged in the hole. The motor controller recognises the increased torque requirement of the second motor 44. The increased torque requirement triggers activation of the first motor 40 which rotates the first motor gear, which drives the drive belt. The drive belt then causes turning of base plate 30. The turning of the base plate 30, inclusive of the grippers 50 that are fractionally engaged with the stopper, disengages the stopper from the hole.

[0074] The motor controller recognises a decreased torque requirement in the first motor 40, which means that the stopper has been disengaged from the hole. The decreased torque requirement triggers deactivation of the first and second motors 40, 44. The stopper may now either be removed from the hole by movement of the robotic arm along axis 31 away from the hole, or by running the second motor 44 backwards such that the grippers 50 move away the axis 31. The stopper is released by the grippers 50 and may now be retrieved manually. [0075] The advantages of the gripping device 10 will now be discussed.

[0076] The flat configuration of the gripping device 10 as shown in Figures 1 to 8 allows the use of the devi ce in the small and confined spaces between stacked wine barrels. Further, as the gripping device 10 is able to be used in smaller and more confined spaces between stacked wine barrels, the storage density of wine barrels in a given facility may be improved.

[0077] The improved capacity of wine storage facilities is a direct financial benefit to a wine producer. Similarly, the ability to increase the sample rate of a given wine barrel allowed the wine producer to detect and correct maturation processes that are not proceeding correctly. This results in fewer spoilt wine barrels and an increase in revenue.

[0078] The gripping device 10 also facilitates the implementation of automated sampling and replenishing processes that are of interest to wine producers. In combination with other devices or equipment the gripping device 10 could be used to provide an automatic sampling process.

[0079] The motor controller allows quick and accurate disengagement of the stopper from the hole. The motorisation of the gripping of the grippers 50 and the turning of the base plate 30 decreases the manual effort required to disengage stoppers from wine barrels and therefore allows the sampling and monitoring of more wine barrels than would be possible with a manual tool.

[0080] The turning of the stopper to disengage it from the hole in a wine barrel is a safer approach than current manual, or tool assisted, methods directed to pulling the stopper from the barrel. Once the stopper has been disengaged by turning it using the gripping device 10 it is a physically trivial task to remove it using a robot arm or manually.

[0081] The location of the second motor 44 atop the retainer plate 70 allows the second motor 44 to remain actuated while the base plate 30 is being turned by the first motor 40. This means that no loss of normal force occurs between the stoppers and grippers 50 as a result of turning the base plate 30 in either direction about the axis 31.

[0082] Although the invention has been described with reference to specific examples, it will be appreciated by those skilled in the art that the invention may be embodied in many other forms. [0083] For example, while in the foregoing embodiments the first and second motors 40, 44 have been described as electric servo motors, any means of providing the desired rotational motion such as springs, ratchets or the like could be used. Similarly, while the embodiments disclose the use of separate motors, the guide plate 60 and base plate 30 could be driven by the same motor using a gear transmission or clutch to cause the motion of the grippers 50 toward the axis 31 and subsequent rotation of the grippers 50.

[0084] The grippers 50 may also have caps made of a material having a higher coefficient of friction, such as silicon or the like, to improve the grip with the stopper. Similarly, the grippers 50 may be shaped at a surface facing the central axis 31, to be substantially congruent with the shape of a stopper to improve the grip with the stopper. Further, the grippers 50 may be knurled, and/or textured, to improve the grip with the stopper.

[0085] While the foregoing embodiments have disclosed the use of simple bearings 32 to allow rotation of the base plate 30, gripper guide 60 and adapter plate 20, other mechanisms to allow the relative motion between these components are conceivable. For example magnetic, hydraulic, PTFE or air bearings could be used to even further reduce the height profile of the gripping device 10.

[0086] The second motor 44 could be mounted on the adapter plate 20. This arrangement would further reduce the vertical profile of the gripping device 10. However, during the rotation of the stopper, using the first motor 40, the second motor 44 would also be required to operate such that the grippers 50 rotate together with the base plate 30.

[0087] The drive recesses 62 could be linear recesses.

[0088] It is also conceivable that the grippers 50 are connected to the gripper guide 60 by protrusions on the gripper guide 60 engaging with drive recesses on the grippers 50.

[0089] In an embodiment, locating means could be provided to facilitate the location of the gripping device 10 in a position to grip the stopper. The locating means could include mechanical guides, electronic sensors or the like.