WO2009013763A2

WO2009013763A2 - Panel unloading and pallet handling system and method for operating the same

Info

Publication number: WO2009013763A2
Application number: PCT/IN2008/000305
Authority: WO
Inventors: Anshuman P. Gour; Abhijit K. Petkar; Divy S. Shrivastav
Original assignee: Tata Motors Limited
Priority date: 2007-07-23
Filing date: 2008-05-14
Publication date: 2009-01-29
Also published as: WO2009013763A3

Abstract

This invention relates to panel unloading and pallet handling system and method for operating the same, said system consists of rotary shuttle with tooling, robots with tooling, panel conveyors, and pallet handling conveyors. Rotary shuttle consists of two arms at 90° to each other and pivoted at pivot point with necessary tooling for accommodating the stamped part and driving mechanism to drive arm from loading point to unloading points. Said shuttle is placed at a centre line of the press line at down stream of last press. Said shuttle is also interlinked with at least two tool changing points and a spare shuttle located at one of the tool changing point. Two robots are symmetrically placed at the downstream of the said shuttle on either side of the press centerline for picking the stamped parts from shuttle and placing on conveyors. Said robots are provided with a facility to have a tool selection option based on requirement. Two panel conveyors are placed at the downstream of the said shuttle and away from said robots on either side of the press centerline at equidistance. Two pallet conveyors are placed on either side of the press centerline at equidistance in between panel conveyors.

Description

PANEL UNLOADING AND PALLET HANDLING SYSTEM AND METHOD FOR OPERATING THE SAME

FIELD OF INVENTION

This invention relates to panel unloading and pallet handling system used in press shop and more particularly it relates to stamped panel unloading and pallet handling system and method thereof at End Of Line (EOL) in press shop.

BACKGROUND OF INVENTION

Conventional tandem line of press system as shown in fig.1 basically comprises of two or more presses (I), robot (II) for unloading panels, conveyor (III) and pallets (IV). Wherein press line runs normally at a rate of 8-10 strokes per minute i.e. the parts are coming out of the last press in every 6-7.5 seconds. The part is unloaded from the last press on a conveyor with the robots or other suitable mechanism. The inspection activity is carried out on the conveyor before unloading the part in the pallet. The filled pallet is replaced by the empty pallets with the help of the forklifts.

The drawbacks associated with this system are:

1. If the press is operated at a speed of above 15 strokes per minute (spm), the robots can not be used for unloading the parts due to kinematics limitations in robotic technology.

2. The online inspection on the conveyor for press speed of above 15 spm is very difficult as conveyor speed is also required to be kept at higher range in order to keep the system streamline.

3. The pallet exchange time with the forklift is higher than the cycle time of parts generation if press speed is above 15 spm. Due to this the number of unloading stations need to be increased and hence the length of the conveyor. This causes poor utilization of space and less logistic efficiency. 4. This system neither has buffer of filled pallets nor empty pallets. This makes the press line vulnerable to stoppage on account of failure to exchange the pallets.

OBJECTS OF INVENTION

Main object of this invention is to provide a panel unloading and pallet handling system and method for operating the same at high speed of press line.

Another object of this invention is to provide a panel unloading and pallet handling system and method for operating the same at high speed of press line with a provision of online inspection

Yet another object of this invention is to provide a panel unloading and pallet handling system and method for operating the same at high speed of press line with optimum space utilization at the end of line

STATEMENT OF INVENTION

Panel unloading and pallet handling system consists of one or more; rotary shuttle for simultaneous loading and unloading of panels, robot, panel conveyor and pallet handling conveyor for exchanging filled pallets with empty pallets within cycle time, wherein said shuttle is placed at a centre line of the press line at down stream of last press and is interlinked with at least two tool changing points; robots are placed at the downstream of the said shuttle on either side of the press centerline for picking stamped panels from shuttle and placing on panel conveyors, panel conveyors are placed at the downstream of the said shuttle and away from press centerline and said robots on either side, pallet conveyors are placed on either side of the press centerline in between panel conveyors.

Panel unloading and pallet handling system wherein said robots, panel conveyors and pallet conveyors are placed at equidistance from said press centre line.

Panel unloading and pallet handling system wherein empty pallets are provided on pallet conveyors to collect stamped panels, filled pallets from pallet conveyors are unloaded.

Panel unloading and pallet handling system wherein said rotary shuttle consists of two arms at 90° to each other and pivoted at pivot point with necessary tooling for accommodating the stamped panels and driving mechanism to drive arms for simultaneous loading and unloading of panels.

Panel unloading and pallet handling system wherein said rotary shuttle consists of at least one spare shuttle located at one of the said tool changing point.

Panel unloading and pallet handling system wherein guiding rails are provided below said shuttle in the direction perpendicular to the press axis to facilitate change of shuttle tool.

Panel unloading and pallet handling system as claimed in claims 1 to 6 wherein said robots are provided with a tool selection option facility to have a desired tool based on requirement.

Panel unloading and pallet handling system wherein said robots are provided with two or more tool holding positions. Method of panel unloading and pallet handling comprises following steps a) Simultaneously, loading stamped panel on shuttle and unloading on panel conveyor; b) Inspecting the stamped panel while moving on panel conveyor; c) Transferring stamped panel in pallets provided on pallet conveyor; d) Exchanging filled pallet with empty pallet within cycle time on pallet conveyor; e) Lifting filled pallets from pallet conveyor.

BRIEF DESCRIPTION OF INVENTION

The End of Line system consists of rotary shuttle with toolings, robots with toolings, panel conveyors, and pallet handling conveyors. Rotary shuttle consists of two arms at 90 to each other and pivoted at pivot point with necessary tooling for accommodating the stamped part and driving mechanism to drive arm from loading point to unloading points. Said shuttle is placed at a centre line of the press line at down stream of last press. Said shuttle is also interlinked with at least two tool changing points and a spare shuttle located at one of the tool changing point.

Two robots are symmetrically placed at the downstream of the said shuttle on either side of the press centerline for picking the stamped parts from shuttle and placing on conveyors. Said robots are provided with a facility to have a tool selection option based on requirement.

Two panel conveyors are placed at the downstream of the said shuttle and away from said robots on either side of the press centerline at equidistance.

Two pallet conveyors are placed on either side of the press centerline at equidistance in between panel conveyors. When un-loader of press line unloads the panel from the last press on rotary shuttle, the shuttle rotates by 90° anticlockwise so that the empty nest takes place of filled nest position. The robot lifts the panel from the filled nest and keeps it on the panel conveyor. Simultaneously, the un-loader lifts panel from the last press and keeps on the empty nest. The shuttle rotates by 90° in clock wise direction keeps it on other panel conveyor. Panels from panel conveyor are discharged to the pallets, which are provided on a pallet conveyor, Filled pallets from the pallet conveyor are transported by a forklifts.

Aforementioned system and method in accordance with this invention yields the following important operations/features

1. Online inspection

2. Exchange of filled pallets and empty pallets within cycle time

3. The buffer for filled and empty pallet.

DETAILED DESCRIPTION OF INVENTION

Referring now to the drawings wherein the showings are for the purpose of illustrating a preferred embodiment of the invention only, and not for the purpose of limiting the same,

Fig.1 shows a conventional end of line system with robots used for unloading and splitting the panel on two conveyors.

Fig. 2 shows the top view of the end of line panel unloading and pallet handling system in accordance with this invention.

Fig. 3 shows the front view of the end of line panel unloading and pallet handling system in accordance with this invention.

Fig. 4 shows the top view and front view of the said rotary shuttle

Fig. 5 shows the top view of the said pallet conveyor Referring to figs. 2 to 5 wherein panel unloading and pallet handling system consists of rotary shuttle (2) with tooling (2D), robots (3A, 3B) with toolings, panel conveyors (4A,4B), and pallet handling conveyors (6). Rotary shuttle (2) consists of two arms (2A,2B) at 90° to each other and pivoted at pivot point (2C). The arms (2A, 2B) are provided with tooling (2D) for accommodating the stamped panel. The driving mechanism (not shown) is fitted below the pivot point to drive arm (2A, 2B) from loading point to unloading points. Said shuttle (2) is placed at a centre line (X-X) of the press line at down stream of last press and is mounted on the wheels. Said shuttle (2) is also interlinked with at least two tools changing points (A, B) and a spare shuttle (2') is located at tool changing point (B). The wheel track (7) is laid in the direction perpendicular to press axis for guiding the shuttle during exchange. The track connects the operating position of the shuttle to tool changing positions (A, B) at either side of press centre line. The shuttle (2) consists of necessary sensors and electronic control system to link with the spare shuttle (2') and the press control system. The shuttle (2) is equipped with clamping mechanism (not shown) to clamp and unclamp the tooling (2D). The tooling (2D) is changed depending upon the size of the part stamped by the press.

Two robots (3A, 3B) are symmetrically placed at the downstream of the said shuttle on either side of the press centerline (X-X) for picking the stamped parts from shuttle and placing on panel conveyors (4A, 4B). There are two tool changing magazines (5 A, 5B), one for each said robot placed at the downstream of robots (3A, 3B). The tool changer (5A, 5B) is rotary indexing device, which has two tool store positions.

Two panel conveyors (4A, 4B) are placed at the downstream of the said shuttle (2) and away from said press centre line (X-X) and robots (3A, 3B) on either side of the press centerline (X-X) at equidistance. Two pallet conveyors (6A, 6B) are placed on either side of the press centerline at equidistance in between panel conveyors (4A, 4B). The conveyor (6A) has two lifting arrangements at position (b) and (d) to enable the cross transfer.

When un-loader (U) of press line unloads the panel from the last press (P) on rotary shuttle (2), the shuttle rotates by 90° anticlockwise so that the empty tooling (2D) takes place of filled tooling position. The robot (3A) lifts the panel from the filled tooling and keeps it on the conveyor. Simultaneously, the un- loader lifts panel from the last press and keeps on the empty tooling. The shuttle (2) rotates by 90° in clock wise direction keeps it on other conveyor. Panels from panel conveyor (4A, 4B) are discharged to the pallets, which are provided on the pallet conveyors (6A, 6B), Filled pallets from the pallet conveyor (6A, 6B) are transported by a forklifts.

The press un-loader unloads the part on the arm (2A) carried by the rotary shuttle (2). The shuttle then rotates anti clockwise to index through 90 degrees say towards left. Now, the arm (2B) comes in front of press along the press flow axis. The un-loader keeps the part on the arm (2B). Simultaneously the Robot (3A) picks the part from the arm (2A). The robot (3A) then put the part on conveyor (4A). The shuttle (2) now rotates clockwise through 90 degrees so that arm (2A) now again comes along the press flow axis in front of un-loader. The robot (3B) picks the part from arm (2B) and unloads on the conveyor (4B).

During the set up change the rotary shuttle is replaced with spare rotary shuttle (2') with toolings for next batch. The robots (3A, 3B) exchange there tools from tool change magazine (5 A, 5B).

The parts are unloaded from panel conveyors (4 A, 4B) into the pallets. The pallets are kept on the pallet conveyor (6 A, 6B). The pallet conveyor system (6) is used to exchange and convey the pallets at the end of the line. The empty pallets are kept on the conveyor (6A) at point (a) with the help of the forklift. The chain conveyor transfers the part at point (b). The system is equipped with lifter at point (b). The lifter lifts the pallet and transfers it in the perpendicular direction to point (c). The chain conveyor moves at a slow speed about 2 m/min form point (c) to point (d).

The operators unload the part in the pallet while is moving from point (c) to Point (d). At point (d), the pallet will again be transferred in cross direction to point (e) with lifter mechanism. The segment of the conveyor from point (e) to point (h) is accumulating conveyor. The pallet will be lifted from point (h) with the forklift. The same process is followed at other part of conveyor (6B).

Method of panel unloading and pallet handling comprises following steps:

a) Receiving stamped panel from press un-loader on one of the arm (2A) of rotary shuttle and simultaneously the panel on another arm (2B) is lifted by robot (3B) and kept on the panel conveyor (4B); b) Rotating shuttle through 90° and press un-loader unloads the part on the arm (2B) of rotary shuttle and simultaneously the panel on another arm (2A) is lifted by robot (3A) and kept on the panel conveyor (4A); c) Unloading panels on panel conveyor (4A, 4B) by robots (3A, 3B); d) Inspecting the stamped panel while moving on panel conveyor; e) Transferring panels to pallets provided on pallet conveyor; f) Exchanging filled pallet with empty pallet on the pallet conveyor (6A, 6B); g) Lifting filled pallet from pallet conveyor (6A, 6B) with the help of a forklift.

Claims

1. Panel unloading and pallet handling system consists of one or more; rotary shuttle for simultaneous loading and unloading of panels, robot, panel conveyor and pallet handling conveyor for exchanging filled pallets with empty pallets within cycle time, wherein said shuttle is placed at a centre line of the press line at down stream of last press and is interlinked with at least two tool changing points; robots are placed at the downstream of the said shuttle on either side of the press centerline for picking stamped panels from shuttle and placing on panel conveyors, ^■ panel conveyors are placed at the downstream of the said shuttle and away from press centerline and said robots on either side, pallet conveyors are placed on either side of the press centerline in between panel conveyors.

2. Panel unloading and pallet handling system as claimed in claim 1 wherein said robots, panel conveyors and pallet conveyors are placed at equidistance from said press centre line.

3. Panel unloading and pallet handling system as claimed in claims 1 and 2 wherein empty pallets are provided on pallet conveyors to collect stamped panels and filled pallets from pallet conveyors are unloaded.

4. Panel unloading and pallet handling system as claimed in claims 1 and 3 wherein said rotary shuttle consists of two arms at 90° to each other and pivoted at pivot point with necessary tooling for accommodating the stamped panels and driving mechanism to drive arms for simultaneous loading and unloading of panels.

5. Panel unloading and pallet handling system as claimed in claims 1 to 4 wherein said rotary shuttle consists of at least one spare shuttle located at one of the said tool changing point.

6. Panel unloading and pallet handling system as claimed in claims 1 to 5 wherein guiding rails are provided below said shuttle in the direction perpendicular to the press axis to facilitate shuttle tool changing.

7. Panel unloading and pallet handling system as claimed in claims 1 to 6 wherein said robots are provided with a tool selection option facility to have a desired tool based on requirement.

8. Panel unloading and pallet handling system as claimed in claims 1 to 7 wherein said robots are provided with two or more tool holding positions.

9. Method of panel unloading and pallet handling comprises following steps: a) Simultaneously, loading stamped panel on shuttle and unloading , on panel conveyor b) Inspecting the stamped panel while moving on panel conveyor; c) Transferring stamped panel in pallets provided on pallet conveyor; d) Exchanging filled pallet with empty pallet within cycle time on pallet conveyor; e) Lifting filled pallets from pallet conveyor.

10. Panel unloading and pallet handling system and method for operating the same substantially as herein described with reference to accompanying drawings.