Handling: hand and hoist-line implements – Grapple
Reexamination Certificate
2000-12-08
2002-10-22
Lillis, Eileen D. (Department: 3652)
Handling: hand and hoist-line implements
Grapple
C294S902000, C294S106000
Reexamination Certificate
active
06467826
ABSTRACT:
THE BACKGROUND OF THE INVENTION AND THE PROBLEM
The present invention relates to a device in tool holders and of the kind which comprises a C-shaped frame, has a preferably long inner range, which frame at its free shank ends carries said tool, for example a riveting, a glueing or a welding unit.
C-shaped frames of the above mentioned kind are previously known and are used for joining of for instance car body components, frame works, train cars, air crafts, etc. They are made as I-shaped section in high tensile steel since high requirements are put on the stiffness and the structural strength of the frame. Particularly when working operations, such as e.g. riveting, is in question, large opening forces arise on the shanks of the C-shaped frame. The frame is also to be exposed to a large number of working cycles and a minimum of 2 million cycles is a demand. The C-frame must be able to operate on deeply situated parts in certain situations i.e, be able to reach a working area which is situated e.g. 1 meter inside an outer limitation. At large scale production in the automotive industry the C-shaped tool holder is being handled by a robot, which means that the weight of the C-frame should be so low that the total weight of the system is less than the allowed operation weight of the robot. At manual operation it is also desired to minimize the mass of the system.
Using the robots of today, one has reached and in some cases also exceeded the weight limit, but the market demands both larger and more stable tool holders with maintained or even lowered weight. The investments in robots are so high that it must be possible to use existing ones even for new and more extensive working operations.
Tests have been made to produce C-shaped frames from composite materials as solid models but the load strains in the intersections in the form, i.a., of shear and tear stresses in the glue joints will become so high, that these tests could not be preformed. A typical steel C-frame, having an inner depth of 850 mm, a gap between the ends of the shanks of 400 mm and a calculated load in the form of opposed directed forces of 53 kN, has a weight of about 150 kg at a maximal permitted deflection of 7 mm; between the ends of the shanks. This weight together with the weight of the necessary tool equipment exceed the carrying and operating capability of the robot and are therefore not acceptable.
THE OBJECT OF THE INVENTION AND THE SOLUTION OF THE PROBLEM
The object of the invention is to provide a tool holder, which:
a. has a low weight,
b. has a high stiffness,
c. has a high strength,
d. has a simple construction,
e. is price-worthy,
f. can easily be varied in shape and form,
g. can operate in difficult environments, e.g., welding sputters,
h. has a long service life and high reliability.
These tasks have been solved by the features defined in the claims.
REFERENCES:
patent: 2875913 (1959-03-01), Gohrke et al.
patent: 3927424 (1975-12-01), Itoh
patent: 4367891 (1983-01-01), Wauer et al.
patent: 4401407 (1983-08-01), Breckenridge
patent: 5092731 (1992-03-01), Jones et al.
patent: 5108140 (1992-04-01), Bartholet
patent: 5378033 (1995-01-01), Guo et al.
patent: 5473852 (1995-12-01), Lindsey
patent: 5501498 (1996-03-01), Ulrich
patent: 5588688 (1996-12-01), Jacobsen et al.
patent: 5762390 (1998-06-01), Gosslin et al.
patent: 6059169 (2000-05-01), Nihei et al.
patent: 6260902 (2001-07-01), Synnelius
patent: 3320874 (1984-12-01), None
patent: 0 291 828 (1988-05-01), None
patent: 8501455 (1986-12-01), None
patent: WO 90/06831 (1990-06-01), None
patent: WO 90/07071 (1990-06-01), None
Fröberg Peter
Hellman Hans
Holm Dan
Strömberg Karl-Otto
C-Power AB
Chin Paul T.
Lillis Eileen D.
Oppedahl & Larson LLP
LandOfFree
Tool 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 Tool holder, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Tool holder will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2959603