CHANGEABLE DEVICE FOR FLAP WHEELS

Description

Technical Field

[0001] The present invention relates to a changing equipment for flap wheels.

[0002] In particular, the present changing equipment for changing flap wheels is usable in robotized cells for sanding and finishing metal workpieces.Background Art

[0003] The robotized cells allow carrying out different operations without the direct intervention of human operators and an articulated robotic arm is housed inside them.

[0004] The use of automated robotic arms makes it possible to replace the manual work of the operators, thus limiting the risks for their safety and significantly reducing processing times.

[0005] The robotic arm is able to pick up a series of tool heads from special locations and to bring them into contact with the metal workpieces.

[0006] Among these, the grinding heads are used, e.g., for finishing and polishing the workpiece using special flap wheels.

[0007] The flap wheels used in the aforementioned grinding heads need to be changed with others of different grind depending on the desired finish or to be replaced after wear.

[0008] However, this generally leads to a lengthening of the processing time with a consequent increase in related costs.

[0009] A special type of apparatus for replacing an abrasive element is disclosed in the patent document WO2019 / 123310.Description of the Invention

[0010] The main aim of the present invention is to devise a changing equipment for flap wheels that allows reducing the time and costs related to this operation. Within this inventive concept, one object of the present invention is to enable the installation of the flap wheels to a grinding head quickly and safely. Another object of the present invention is to devise a changing equipment for flap wheels that allows overcoming the aforementioned drawbacks of the prior art within a simple, rational, easy, effective to use and low cost solution.

[0011] The aforementioned objects are achieved by the present changing equipment for flap wheels having the characteristics of claim 1.Brief Description of the Drawings

[0012] Other characteristics and advantages of the present invention will be more evident from the description of a preferred, but not exclusive, embodiment of a changing equipment for flap wheels, illustrated by way of an indicative, yet non-limiting example, in the attached tables of drawings wherein: Figure 1 is a plan view of a changing station for flap wheels comprising a changing equipment according to the invention; Figure 2 is a top view of a component of the changing equipment for flap wheels according to the invention; Figure 3 is a front view of a component of the changing equipment for flap wheels according to the invention; Figure 3a is a front view of the component in Figure 3 in a different operational configuration; Figure 4 is a partly sectional side view of a component of the changing equipment for flap wheels according to the invention; Figure 5 is a partly sectional side view of the component in Figure 4 in a different operational configuration; Figure 5a is a front view of a component of the changing equipment for flap wheels according to the operational configuration in Figure 5; Figure 6 is a partly sectional side view of the component in Figure 4 in a further different operational configuration; Figure 7 is an axonometric view of a component of the changing equipment for flap wheels according to the invention; Figure 8 is an axonometric view of the component in Figure 7 in a different operational configuration; Figure 9 is an axonometric view of the component in Figure 7 in a further different operational configuration. Embodiments of the Invention

[0013] With particular reference to these figures, reference numeral 1 globally indicates a changing station for flap wheels.

[0014] The station 1 is usable in robotized cells for sanding and finishing metal workpieces through the aid of an articulated robotic arm.

[0015] The robotic arm is able to pick up a series of tool heads from special locations and to bring them into contact with the metal workpieces to be processed.

[0016] The station 1, in particular, is adapted to replace a flap wheel 2 to a grinding head T.

[0017] The flap wheel 2 is provided with a threaded element 2a.

[0018] The threaded element 2a is adapted to engage with a respective threaded hole defined on the grinding head T.

[0019] The station 1 according to the invention comprises at least one changing equipment 3 for flap wheels.

[0020] The changing equipment 3 comprises gripping means 4 for gripping at least one flap wheel 2 applicable to the grinding head T.

[0021] The changing equipment 3 also comprises at least one screwing unit 5 which is operationally connected to the gripping means 4 and which is adapted to set the gripping means 4 in rotation to screw / unscrew the flap wheel 2 to / from the grinding head T.

[0022] The gripping means 4 comprise a main body 4a connected to the screwing unit 5 and movable in rotation to screw / unscrew the flap wheel 2.

[0023] The gripping means 4 comprise at least two gripping elements 6 defining a housing seat 7 of the flap wheel 2.

[0024] The gripping elements 6 are associated with the main body 4a on the opposite side to the screwing unit 5.

[0025] With reference to a preferred embodiment shown in detail in the figures, the gripping means 4 comprise three gripping elements 6, in order to ensure a better grip of the flap wheel 2.

[0026] The housing seat 7 is substantially circular and the gripping elements 6 are arranged radially with respect to the center C of the circumference.

[0027] After being grasped by means of the gripping elements 6, the flap wheel 2 occupies the housing seat 7 so that the threaded element 2a faces the grinding head T.

[0028] At least one of the gripping elements 6 is movable with respect to the other of the gripping elements 6 to intercept / release the flap wheel 2.

[0029] According to a preferred embodiment, the gripping means 4 comprise a self-centering spindle provided with three gripping elements 6 which are adapted to close simultaneously for gripping and centering the flap wheel 2.

[0030] Specifically, the gripping elements 6 move towards the center C so as to grip the flap wheel 2 and, in the same way, they move away from the center C to release the flap wheel 2.

[0031] In other words, the gripping elements 6 are movable between an open position and a closed position to release and retain the flap wheel 2, respectively.

[0032] Figures 3 and 3a show the mutual positions of the gripping elements 6 in the open position and in the closed position.

[0033] The gripping elements 6 are moved by a compressed air system.

[0034] The special solution of using a self-centering spindle causes the flap wheel 2 to be engaged with the gripping means so that the threaded element 2a is always at the point where the center C is located, aligned with the respective threaded hole of the grinding head T.

[0035] Conveniently, the screwing unit 5 comprises at least one crankshaft 8 associated with the gripping means 4.

[0036] The crankshaft 8 is set in rotation by a motor and transfers the rotational motion to the gripping means 4 to screw and / or unscrew the flap wheel 2.

[0037] More specifically, the gripping means 4 comprise a drive shaft associated with the main body 4a and adapted to transfer the rotational motion from the crankshaft 8 to the main body itself.

[0038] The crankshaft 8 is movable in at least one of a clockwise and an anticlockwise direction.

[0039] Advantageously, the crankshaft 8 rotates both clockwise and anticlockwise. This way, the screwing unit 5 is both able to screw and unscrew the flap wheel 2.

[0040] Conveniently, the gripping means 4 and the screwing unit 5 are arranged substantially coaxial with respect to a first axis A1 defined by the crankshaft 8 and passing through the center C.

[0041] The gripping means 4 and the screwing unit 5 are in fact aligned and are arranged resting on a substantially horizontal holding plane 9.

[0042] The changing equpament 3 comprises at least one supporting body 16 of the gripping means 4.

[0043] In particular, the gripping means 4 are associated with the supporting body 16 and movable in rotation with respect to the supporting body 16.

[0044] In particular, the supporting body 16 defines a substantially cylindrical cavity, inside which the main body 4a is at least partly housed.

[0045] The supporting body 16 is associated movable with the holding plane 9.

[0046] The supporting body 16 is movable along the first axis A1 to displace the gripping means 4 with respect to the grinding head T.

[0047] In particular, the gripping means 4 are movable between a close position wherein the gripping elements 6 are in the proximity of the grinding head T and a far-away position wherein the gripping elements 6 are moved away from the grinding head T.

[0048] Conveniently, the changing equipment 3 comprises movement means 13 of the gripping means 4.

[0049] The movement means 13 are associated with the supporting body 16 and are adapted to displace the gripping means 4 along the first axis A1.

[0050] The movement means 13 are adapted to position the gripping means 4 in the proximity of the grinding head T during the screwing in / unscrewing of the flap wheel 2.

[0051] The movement means 13 comprise at least one pneumatic cylinder.

[0052] The pneumatic cylinder is associated with the supporting body 16.

[0053] In particular, the pneumatic cylinder is connected at one end to the supporting body 16 and at the other end it is associated with the holding plane 9.

[0054] The changing equipment 3 also comprises guiding means 14, 15 of the gripping means 4 between the close position and the far-away position.

[0055] According to a possible embodiment, the guiding means comprise one guiding element 14 associated with the holding plane 9 and at least one movable element 15 associated sliding with the aforementioned guiding element 14.

[0056] The guiding element 14 is of a rail type and is arranged substantially parallel to the first axis A1.

[0057] The movable element 15, on the other hand, is associated with the supporting body 16.

[0058] Basically, the supporting body 16 is associated with the holding plane 9 through the movable element 15.

[0059] Advantageously, the changing equipment 3 comprises synchronization means between the screwing unit 5 and the movement means 13 to move the gripping means 4 towards the close position when the crankshaft 8 rotates clockwise, and to move the gripping means 4 towards the far-away position when the crankshaft 8 rotates anticlockwise.

[0060] Substantially, the synchronization means facilitate the screwing in of the flap wheel 2 by moving the gripping means 4 close to the grinding head T and in the same way, they facilitate the unscrewing thereof by moving the gripping means 4 away from the grinding head T.

[0061] The changing equipment 3 also comprises retaining means 10 of the grinding head T during the screwing in / unscrewing of the flap wheel 2.

[0062] The retaining means 10, in fact, have the function of keeping the grinding head T stationary so as to optimize the screwing in / unscrewing operation.

[0063] The retaining means 10 usefully comprise at least one retaining element 11 adapted to intercept the grinding head T and to prevent the movement thereof during the screwing in / unscrewing of the flap wheel 2.

[0064] In more detail, the retaining element 11 comprises a retaining portion 11a which is adapted to engage with the grinding head T.

[0065] As shown in detail in Figure 5a, the retaining portion 11a is of the type of a fork wrench.

[0066] The retaining element 11 is movable along a second axis A2 substantially transverse to the first axis A1, between a retaining position wherein it intercepts a corresponding portion of the grinding head T and a release position wherein it is moved away from the grinding head T.

[0067] Advantageously, the second axis A2 is substantially orthogonal to the first axis A1.

[0068] In even more detail, the second axis A2 is substantially vertical.

[0069] The retaining means 10 comprise an actuating device 12 for the movement of the retaining element 11 between the retaining position and the release position. In this case, the actuating device 12 is of the type of a pneumatic cylinder. Conveniently, the station 1 comprises a storage location 17 which is adapted to accommodate a plurality of flap wheels 2 which can be installed on the grinding head T.

[0070] The flap wheels 2 are taken from the storage location 17 to be positioned in the housing seat 7 of the gripping means 4.

[0071] The storage location 17 comprises at least one resting base 18 of the flap wheels 2 associated with a trolley 19.

[0072] The resting base 18 is substantially horizontal and the flap wheels 2 are arranged thereon resting so that the threaded element 2a is facing upwards.

[0073] The storage location 17 comprises a load-bearing structure with which the trolley 19 is associated movable between an operating position, wherein it is arranged inside an operating area for the picking of the flap wheels 2, and a home position wherein it is moved away from the operating area.

[0074] More specifically, in the home position, the trolley 19 is located in a loading area wherein the flap wheels 2 can be positioned on the resting base 18 by an operator.

[0075] Advantageously, the storage location 17 comprises at least one motor assembly 20 operationally connected to the trolley 19 and adapted to move the trolley 19 between the operating position and the home position.

[0076] In more detail, the trolley 19 is connected to the motor assembly 20 via a toothed belt.

[0077] The toothed belt is set in motion by a pulley associated with the motor assembly itself.

[0078] Conveniently, the storage location 17 comprises a plurality of trolleys 19.

[0079] The trolleys 19 are movable the one with respect to the other so that at least one of the trolleys 19 is positioned in the operating area and, therefore, the flap wheels 2 are always available for the grinding head T.

[0080] The storage location 17 comprises at least one pair of trolleys 19.

[0081] The trolleys 19 are connected to each other by means of the toothed belt so that when one trolley 19 is brought towards the loading area, the other trolley 19 moves towards the operating area.

[0082] Advantageously, the station 1 comprises a transferring apparatus 21 for transferring the flap wheel 2 from the storage location 17 to the gripping means 4.

[0083] The transferring apparatus 21 is of the type of an auxiliary articulated robotic arm and is provided with a gripper 21a which is able to hold the threaded element 2a of the flap wheel 2 and to arrange the latter at the point where the gripping elements 6 are located.

[0084] Specifically, the gripper 21a is of the type of a self-centering gripper.

[0085] The transferring apparatus 21 causes that, once the flap wheel 2 has been positioned in the housing seat 7, the threaded element 2a is facing the grinding head T.

[0086] The operation of the present invention is as follows.

[0087] Initially, the gripping means 4 are in the home position, with the gripping elements 6 open, and the retaining element 11 is in the release position.

[0088] When the flap wheel 2 is replaced, the gripping means 4 are moved towards the close position by the movement means 13.

[0089] The grinding head T is moved close to the station 1 thanks to the automated robotic arm.

[0090] In particular, the grinding head T is moved close to the changing equipment 3 and the flap wheel 2 is positioned in the housing seat 7 (Figure 4).

[0091] The retaining element 11 is moved towards the retaining position and the retaining portion 11a engages with the grinding head T (Figures 5 and 5a).

[0092] The gripping elements 6 close to retain the flap wheel 2.

[0093] At this point, the synchronization means cause the screwing unit 5 to set the crankshaft 8 in rotation anticlockwise, to unscrew the flap wheel 2 and, at the same time, the gripping means 4 move away from the grinding head T to remove the flap wheel 2 from the grinding head itself (Figure 8).

[0094] The retaining element 11 is then moved towards the release position and the grinding head T is moved away from the changing equipment 3.

[0095] The transferring apparatus 21 is moved towards the flap wheel 2 and holds it through the threaded element 2a, the gripping elements 6 open to release the flap wheel 2.

[0096] The transferring apparatus 21 stores the used flap wheel 2 and takes a new one from the storage location 17.

[0097] Afterwards, the transferring apparatus 21 places the flap wheel 2 in the housing seat 7 and the gripping elements 6 close to stop the flap wheel 2 (Figure 6). The transferring apparatus 21 is moved away from the gripping means 4.

[0098] The retaining element 11 is brought back again to the retaining position, the grinding head T is moved close to the gripping means 4 and engages with the retaining portion 11a (Figure 7).

[0099] The gripping means 4 are moved towards the grinding head T so that the threaded element 2a moves close the threaded hole.

[0100] At this point, the screwing unit 5 sets the crankshaft 8 in rotation clockwise so that the gripping means 4 screw the flap wheel 2 to the grinding head T (Figure 8).

[0101] The new flap wheel 2 is installed on the grinding head T.

[0102] The retaining element 11 returns to the release position and the gripping elements 6 open; at the same time, the movement means 13 move the gripping means 4 towards the far-way position (Figure 9).

[0103] Finally, the grinding head T moves away from the station 1 to carry out the finishing operations.

[0104] It has in practice been ascertained that the described invention achieves the intended objects and in particular it is underlined that the changing equipment for flap wheels makes it possible to reduce times and costs related to the operation of replacing the flap wheels from their respective grinding heads. The changing equipment for flap wheels allows the flap wheels to be installed to a grinding head quickly and safely.

Claims

1. Changing equipment (3) for flap wheels, comprising: - gripping means (4) for at least one flap wheel (2) applicable to a grinding head (T), said flap wheel (2) being provided with a threaded element (2a); - at least one screwing unit (5) operationally connected to said gripping means (4) and adapted to set said gripping means (4) in rotation to screw / unscrew said flap wheel (2) to / from said grinding head (T); and - retaining means (10) of said grinding head (T) during the screwing in / unscrewing of said flap wheel (2); characterized by the fact that said gripping means (4) comprise at least two gripping elements (6) defining a housing seat (7) of said flap wheel (2); wherein said housing seat (7) is substantially circular and said gripping elements (6) are arranged radially with respect to the center (C) of the circumference; wherein at least one of said gripping elements (6) is movable with respect to the other of said gripping elements (6) to intercept / release said flap wheel (2); and wherein said gripping means (4) comprise a self-centering spindle adapted to close simultaneously for gripping and centering said flap wheel (2).

2. Changing equipment (3) according to claim 1, characterized by the fact that said screwing unit (5) comprises at least one crankshaft (8) associated with said gripping means (4).

3. Changing equipment (3) according to claim 2, characterized by the fact that said crankshaft (8) is movable in at least one of a clockwise and an anticlockwise direction.

4. Changing equipment (3) according to claim 2 or 3, characterized by the fact that said gripping means (4) and said screwing unit (5) are arranged substantially coaxial with respect to a first axis (A1) defined by said crankshaft (8) and passing through said center (C).

5. Changing equipment (3) according to claim 4, characterized by the fact that it comprises at least one supporting body (16) of said gripping means (4), wherein said gripping means (4) are associated with said supporting body (16) and movable in rotation with respect to said supporting body (16), said supporting body (16) being movable along said first axis (A1) to displace said gripping means (4) between a close position and a far-away position.

6. Changing equipment (3) according to claim 4 or 5, characterized by the fact that it comprises movement means (13) of said gripping means (4), said movement means (13) being adapted to displace said gripping means (4) along said first axis (A1) during the screwing in / unscrewing of said flap wheel (2).

7. Changing equipment (3) according to claim 6, characterized by the fact that said movement means (13) comprise at least one pneumatic cylinder.

8. Changing equipment (3) according to claim 6 or 7, characterized by the fact that said movement means (13) comprise guiding means (14, 15) of said gripping means (4) between said close position and said far-away position, said guiding means (14, 15) being arranged substantially parallel to said first axis (A1).

9. Changing equipment (3) according to one or more of claims 6-8, characterized by the fact that it comprises means of synchronization between said screwing unit (5) and said movement means (13) to move said gripping means (4) towards said close position when said crankshaft (8) rotates clockwise, and to move said gripping means (4) towards said far-away position when said crankshaft (8) rotates anticlockwise.

10. Changing equipment (3) according to one or more of claims 4-9, characterized by the fact that said retaining means comprise at least one retaining element (11) adapted to intercept said grinding head (T) and to prevent the movement thereof during the screwing in / unscrewing of said flap wheel (2), said retaining element (11) being movable along a second axis (A2) substantially transverse to said first axis (A1), between a retaining position wherein it intercepts said grinding head (T) and a release position wherein it is moved away from said grinding head (T).

11. Changing equipment (3) according to claim 10, characterized by the fact that said second axis (A2) is substantially perpendicular to said first axis (A1).

12. Changing equipment (3) according to one or more of claims 10-11, characterized by the fact that said retaining means (10) comprise an actuating device (12) for the movement of said retaining element (11) between said retaining position and said release position.

13. Changing equipment (3) according to claim 12, characterized by the fact that said actuating device (12) is of the type of a pneumatic cylinder.

14. Changing station (1) for flap wheels comprising at least one changing equipment (3) according to one or more of claims 1-13, wherein it comprises at least one storage location (17) adapted to accommodate a plurality of said flap wheels (2) which can be installed on said grinding head (T).