Work holders – With fluid means – Cylinder-piston means in series with additional positioning...
Reexamination Certificate
1999-04-27
2001-08-14
Hail, III, Joseph J. (Department: 3723)
Work holders
With fluid means
Cylinder-piston means in series with additional positioning...
Reexamination Certificate
active
06273408
ABSTRACT:
TECHNICAL FIELD
The present invention relates to fluid pressure actuated grippers of the type employed in automated workpiece handling devices which clampingly grip and transfer a workpiece from one station to another. More particularly, the present invention relates to fluid pressure actuated grippers which can be locked in either or both of their closed or open positions and which are assembled from a plurality of modular or interchangeable components.
BACKGROUND ART
Fluid pressure actuated grippers are widely employed and typically take the form of a pneumatic or hydraulic differential motor whose cylinder is fixedly mounted to a transfer device. At the forward or rod end of the cylinder housing, a gripper jaw mounting structure is fixedly mounted on the cylinder to pivotally support a pair of opposed gripper jaws which are coupled to the piston rod of the motor by a linkage so arranged that upon movement of the piston in one direction the jaws are pivoted to an open position and upon movement of the piston in the opposite direction the jaws are driven to a closed workpiece gripping position.
In typical operation, the gripper jaws will be closed upon a workpiece near the edge of the workpiece and the gripper will be advanced to position the gripped workpiece in operative relationship with a work station. The gripper will then be opened to release the workpiece and the transfer device will retract the gripper from the work station while the work operation is performed. At the conclusion of the work operation, the gripper will then advance back into the work station and the jaws will again close upon the workpiece and carry it away from the work station. Opening and closing the gripper jaws thus takes place when the gripper is in its closest proximity to tooling at the work station.
There are basically two types of linkage arrangements used in fluid pressure actuated grippers to connect the gripper jaws to the piston rods and effect movement of the gripper jaws. These are pivotable link arrangements and pivotal cam arrangements. An example of a pivotal link arrangement can be found in U.S. Pat. No. 5,152,568 to Blatt which discloses pivotal links 36 and 40 that cooperate with gripper jaws 12A and 12B as shown in FIG.
3
.
U.S. Pat. No. 4,518,187 to Blatt et al. discloses a pivotal cam arrangement in which jaw plates 45 and 47 are pivoted by the cooperation of cam slots 61 provided in the jaw plates and a pivot pin 37 (and rollers 39) attached to the piston rod.
In a typical production line there are numerous work stations with one or more fluid pressure actuated gripper devices positioned between adjacent work stations. During operation, all of the gripper devices are synchronized so that they simultaneously remove a workpiece from one work station and transfer the workpiece to the next work station. In such an operation, a problem can occur if any one of the gripper devices fails to properly grip a workpiece. For example if a workpiece slips from its initial gripped position it can become sufficiently out of alignment to prevent its transfer to a succeeding gripper device. A more serious problem can occur if a workpiece is transferred in a misaligned manner and subsequently positioned at a work station in a misaligned fashion. Such an incident can damage the work station. Another problem which can occur is completely losing grip of a workpiece and dropping the workpiece. Losing grip of a workpiece can occur when there is a leak or failure of fluid pressure supplied to the piston rod actuator.
Fluid pressure actuated grippers are generally designed for use with particular workpieces to be transferred and with specific work stations. For example, some workpieces and/or work stations may require wider or narrower gripper jaws, different types of gripper jaws, gripper jaws that open at different angles, different clearance requirements, etc. Because of the wide variety of design or performance options required of grippers, manufacturing facilities which utilize fluid actuated grippers typically have numerous sets of grippers which are designed to transport different workpieces between specific work stations. The requirement of stocking multiple sets of grippers adds to the manufacturer's costs.
The present invention is directed to fluid pressure actuated grippers which overcome and prevent problems associated with fluid pressure leaks or failures. Moreover, the present invention is directed to fluid pressure actuated grippers which are assembled from a plurality of modular or interchangeable components.
REFERENCES:
patent: Re. 34120 (1992-11-01), Plahn
patent: 229670 (1880-07-01), Carrick
patent: D. 230826 (1974-03-01), Menshen
patent: D. 296546 (1988-07-01), Sachs
patent: 320436 (1885-06-01), Hock
patent: 377114 (1888-01-01), Pague
patent: 490150 (1893-01-01), Low
patent: 659532 (1900-10-01), Jordan
patent: 688230 (1901-12-01), Isgrig et al.
patent: 699358 (1902-05-01), Wilson
patent: 746360 (1903-12-01), McAdams
patent: 1468110 (1923-09-01), Howe
patent: 1472566 (1923-10-01), Oishei
patent: 1494033 (1924-05-01), Stevens
patent: 1543037 (1925-06-01), Teeter
patent: 1590227 (1926-06-01), Britton
patent: 1929361 (1933-10-01), Liljebladh
patent: 1929807 (1933-10-01), Casper
patent: 1940258 (1933-12-01), Lautz
patent: 1955226 (1934-04-01), Chavannes
patent: 1986149 (1935-01-01), Harris
patent: 2081749 (1937-05-01), Kritzler et al.
patent: 2141945 (1938-12-01), Tweedale
patent: 2168988 (1939-08-01), Hultquist
patent: 2188514 (1940-01-01), Moore
patent: 2198623 (1940-04-01), Kastler
patent: 2212156 (1940-08-01), Erdley
patent: 2295051 (1942-09-01), Roth
patent: 2381657 (1945-08-01), Eksergian et al.
patent: 2452406 (1948-10-01), Volkery et al.
patent: 2452409 (1948-10-01), Volkery et al.
patent: 2469542 (1949-05-01), Becker
patent: 2499136 (1950-02-01), Edlund et al.
patent: 2565793 (1951-08-01), Weismantel
patent: 2651026 (1953-09-01), Roth
patent: 2769895 (1956-11-01), Boord
patent: 2776168 (1957-01-01), Schweda
patent: 2791623 (1957-05-01), Lock et al.
patent: 2825601 (1958-03-01), Doty
patent: 2858522 (1958-10-01), Wengen et al.
patent: 3146982 (1964-09-01), Budnick
patent: 3349927 (1967-10-01), Blatt
patent: 3350132 (1967-10-01), Ashton
patent: 3482830 (1969-12-01), Sendoykas
patent: 3568959 (1971-03-01), Blatt
patent: 3613904 (1971-10-01), Blatt
patent: 3635514 (1972-01-01), Blatt
patent: 3664654 (1972-05-01), Manville
patent: 3677584 (1972-07-01), Short
patent: 3712415 (1973-01-01), Blatt et al.
patent: 3920295 (1975-11-01), Speckin
patent: 3975068 (1976-08-01), Speckin
patent: 4275872 (1981-06-01), Mullis
patent: 4307864 (1981-12-01), Benoit
patent: 4355922 (1982-10-01), Sato
patent: 4382572 (1983-05-01), Thompson
patent: 4453755 (1984-06-01), Blatt
patent: 4473249 (1984-09-01), Valentine et al.
patent: 4480497 (1984-11-01), Locher
patent: 4495834 (1985-01-01), Bauer et al.
patent: 4515336 (1985-05-01), Fischer
patent: 4596415 (1986-06-01), Blatt
patent: 4708297 (1987-11-01), Boers
patent: 4805938 (1989-02-01), Redmond et al.
patent: 4941481 (1990-07-01), Wagenknecht
patent: 4957318 (1990-09-01), Blatt
patent: 5016850 (1991-05-01), Plahn
patent: 5069433 (1991-12-01), Womack
patent: 5192058 (1993-03-01), Van Dalsem et al.
patent: 5261715 (1993-11-01), Blatt et al.
patent: 5271651 (1993-12-01), Blatt et al.
patent: 5299847 (1994-04-01), Blatt et al.
patent: 5941513 (1999-08-01), Moilanen et al.
McIntosh Bruce D.
Moilanen Steven M.
Barnes & Thornburg
Hail III Joseph J.
PHD, Inc.
Thomas David B
LandOfFree
Mounting bracket for modular workpiece holder does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Mounting bracket for modular workpiece holder, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Mounting bracket for modular workpiece holder will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2462168