Conveyors: power-driven – With means to facilitate working – treating – or inspecting... – Means to convey a palleted load back and forth between an...
Reexamination Certificate
1998-11-24
2001-02-27
Olszewski, Robert P. (Department: 3652)
Conveyors: power-driven
With means to facilitate working, treating, or inspecting...
Means to convey a palleted load back and forth between an...
C029S03300H, C198S465100
Reexamination Certificate
active
06193048
ABSTRACT:
BACKGROUND OF THE INVENTION
Automatic machining centers are previously known which employ a bed which is movable in a horizontal plane in two dimensions. It is also previously known to employ an automatic pallet changer employing a receiver positioned on the bed and having a draw plate for up and down motion of a pallet resting on the draw plate. Such a receiver is disclosed in U.S. Pat. No. 5,492,214. Parts being machined in the automatic machining center are fixed to the pallet by an operator.
Such machining centers have a vertically sliding door for closing off an entrance into the machining center enclosure. At the beginning or end of the machining, the pallet is either moved into or out of the machining enclosure by the automatic pallet changer. When the pallet is outside the enclosure, then it is accessible for a worker to either remove or mount the workpiece being machined.
It has been previously known in U.S. Pat. No. 5,3436,051 to provide a manual pallet change system.
It has been previously disclosed in U.S. application Ser. No. 575,138, entitled “Automatic End Loading Pallet System filed Dec. 19, 1995 recently issued into U.S. Pat. No. 5,813,514, and incorporated by reference herein, to automatically move first and second pallets into or out of the machining enclosure of the machining center. There, first and second pallets are employed so that the worker can be working on one of the pallets while it is outside the machining center while the other pallet is inside the machining enclosure. The pallets can then be automatically exchanged.
Finally, in another type of known automatic pallet system, an automatic pallet changer is provided where first and second tracks are provided side-by-side, with each track having a respective pallet associated with it. A bicycle chain-like horizontal loop is provided between the two tracks. A single dog is provided on the bicycle chain for ultimately engaging with the two pallets. Thus, one pallet is pulled out of the machine center enclosure and thereafter the second pallet is brought into the enclosure as the chain continues rotation.
Disadvantages of the previous systems, and particularly the system disclosed in the '851 patent, are: 1) cost of manufacture is high; 2) the design presents some reliability drawbacks; and 3) the actual pallet change time is excessive.
SUMMARY OF THE INVENTION
It is an object of the present invention to 1) lower the cost of manufacture; 2) improve the reliability of the product; and 3) to improve it s performance through improved cycle times.
According to the invention, an automatic pallet changer system is provided for an automatic machining center, the automatic machining center having an enclosure with an automated machine tool therein and a receiver on a bed moveable in two dimensions horizontally for carrying the pallet with the workpiece thereon which is being machined. A first track is provided for receiving a first pallet having a first workpiece thereon and a second track is provided for receiving a second pallet having a second workpiece thereon. The first and second tracks are arranged side-by-side. The tracks extend from a region outwardly of the enclosure to a region inside the enclosure adjacent the receiver. A linear drive unit is arranged between the first and second tracks and has a carriage which moves along a longitudinally extending carriage guide. The carriage has a member for engaging with the first or second pallet, depending upon whether the linear drive unit is rocked to the right or to the left. A motor is connected to the linear drive unit for causing a movement of the carriage along the carriage guide. A rocker unit is connected to the linear drive unit for rocking the linear carriage unit to the left or to the right.
REFERENCES:
patent: 4747193 (1988-05-01), Hashidate et al.
patent: 4970765 (1990-11-01), Sakawa et al.
patent: 4996754 (1991-03-01), Kitamura
patent: 5044486 (1991-09-01), Kitamura
patent: 5259494 (1993-11-01), Hirose
patent: 5346051 (1994-09-01), Keith
patent: 5370212 (1994-12-01), Mizutani et al.
patent: 5429461 (1995-07-01), Mukherjee et al.
patent: 5492214 (1996-02-01), Keith
patent: 5813514 (1998-09-01), Keith
patent: 5826692 (1998-10-01), Blanc
patent: 3111706 (1982-01-01), None
patent: 404063658 (1992-02-01), None
Midaco Corporation—Automatic Pallet Systems—Series 20A-30A-40A.
Midaco Corporation—Automatic Pallet Systems—Series 30A-40A.
McAllister Steven B.
Midaco Corporation
Olszewski Robert P.
Patents+TMS
LandOfFree
Pallet changer does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Pallet changer, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Pallet changer will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2611580