Metal deforming – By use of tool acting during relative rotation between tool... – Tool orbiting or rotating about an axis
Reexamination Certificate
2000-05-03
2001-05-22
Tolan, Ed (Department: 3725)
Metal deforming
By use of tool acting during relative rotation between tool...
Tool orbiting or rotating about an axis
C072S082000, C072S084000, C072S094000
Reexamination Certificate
active
06233993
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a method for forming a portion of a workpiece, such as a cylinder or shell, and an apparatus therefor, especially the method and apparatus for forming the portion of the workpiece by spinning to form a changed diameter portion of the workpiece, such as a reduced diameter portion of the cylinder.
2. Description of the Related Arts
As for the method for forming a changed diameter portion of a cylindrical member (hereinafter, simply referred to as a cylinder), Japanese Utility-model Laid-open Publication No. 61-110823 discloses a method for forming a cone portion and a body portion by increasing or reducing a diameter of the cylinder to produce a case for holding a catalyst, and reducing a diameter of an open end portion of the case except for the body portion thereof, by a spinning process, to form the other cone portion and a conduit connected thereto in a body. In Japanese Patent Laid-open Publication No. 3-226327, there is disclosed a method for pressing a tubular member longitudinally by a press die to be formed into an approximately conical shape, then rotating the tubular member and pressing a spinning roll onto the outer surface of the portion formed into the conical shape to perform the spinning process, thereby to form an opening portion of a pressure case or the like.
In the mean time, with respect to an outer shell of a catalytic converter or a muffler of an automotive vehicle, it is demanded to produce it easily, and mount it easily in the vehicle, and it is desired to produce it integrally from a metal tube. In this situation, it has been desired to form the reduced diameter portion to be formed on the end portion of the tubular portion, into an unusual shape, such as the one having an offset axis or an oblique axis inclined to a central axis of the cylinder. According to prior methods for forming the cylinder or shell by the spinning process, however, the reduced diameter portion was formed to be coaxial with the main body of the cylinder. In order to produce the cylinder, the main body of which is not coaxial with the reduced portion, therefore, the cone portion (reduced diameter portion) as shown in the right side in FIG. 1 of the above Publication No. 61-110823 was formed by the press working, and then the cone portion was connected to the case body by welding or the like. According to those methods, however, the produced cylinder can not be expected to be so strong, comparing with that of the integral construction. Furthermore, they need the connecting process, different from the forming process, so that it is difficult to produce the cylinder by those methods. As a result, the manufacturing cost of the cylinder shall be increased, comparing with the cylinder of the coaxial type formed by the spinning process.
SUMMARY OF THE INVENTION
Accordingly, it is an object of the present invention to provide a method for forming a changed diameter portion of a workpiece such as a cylindrical member, easily and properly by a spinning process.
It is another object of the present invention to provide an apparatus for forming a changed diameter portion of a workpiece such as a cylindrical member, easily and properly by a spinning process.
In accomplishing the above and other objects, the method for forming the changed diameter portion of the workpiece by spinning may comprise supporting the workpiece so that a central axis of the portion to be processed is aligned with one of a plurality of forming target axes, the plurality of forming target axes being provided on the basis of a plurality of target processed portions of the workpiece changed from the unprocessed portion to a final target processed portion of the workpiece with a central axis of the final target processed portion being at least one of offset from, oblique to and skewed from a central axis of the unprocessed portion, and molding the portion to be processed by a spinning process so that the central axis of the portion to be processed is matched to each forming target axis of the plurality of forming target axes, and simultaneously changing the diameter of the portion to be processed, in each forming target axis.
The apparatus for forming the changed diameter portion of the workpiece may comprise devices for performing the steps as described above. For example, the apparatus may include a rotatable member rotatable about a main axis, and at least one roller operatively mounted on the rotatable member to be radially movable to and from the main axis, and in contact with a surface of the portion to be processed. In the apparatus, a first driving device may be provided for moving at least one of the workpiece and the at least one roller relative to each other so that a central axis of the portion to be processed is aligned with one of a plurality of forming target axes, the plurality of forming target axes being provided on the basis of a plurality of target processed portions of the workpiece changed from the unprocessed portion of the workpiece to a final target changed diameter portion of the workpiece with a central axis of the final target processed portion being at least one of offset from, oblique to and skewed from a central axis of the unprocessed portion. A second driving device may be provided for moving the at least one roller radially toward each forming target axis of the plurality of forming target axes, with the at least one roller being in substantial contact with the surface of the portion to be processed and rotating the at least one roller about the main axis relative to the workpiece. A controller controls the first and second driving means to form the portion to be processed into the final target changed diameter portion.
According to the method and apparatus as described above, the changed diameter portion may be formed to provide a tapered portion, with the diameter of the workpiece gradually changed from an unprocessed portion of the workpiece toward an end of the changed diameter portion. The changed diameter portion may be formed to provide the tapered portion and a neck portion of a tubular configuration extending from the tapered portion.
REFERENCES:
patent: 1500261 (1924-07-01), Page
patent: 3340713 (1967-09-01), Webb
patent: 3477264 (1969-11-01), Sohlemann
patent: 3533259 (1970-10-01), Marcouitch
patent: 4061009 (1977-12-01), Kaporovich
patent: 4143535 (1979-03-01), Bouman
patent: 4563887 (1986-01-01), Bressan et al.
patent: 5570603 (1996-11-01), Chatterly et al.
patent: 5758532 (1998-06-01), Massee
patent: 5901595 (1999-05-01), Massee
patent: 5937516 (1999-08-01), DeSousa et al.
patent: 5996386 (1999-12-01), Pazzaglia
patent: B2-54-41271 (1979-12-01), None
patent: U-61-110823 (1986-07-01), None
patent: 3-146232 (1991-06-01), None
patent: 3-226327 (1991-10-01), None
patent: B2-2534530 (1996-06-01), None
Mathew, P., “Eccentric Metal Spinning-A New Method to Produce Multi-Recessed Parts”, Metallurgia and Metal Forming, Dec. 1974, pp. 378-379.
Sereda, V.G., “Calculation of the Energy and Force Parameters in Planetary Rolling of Tubular Blanks,” Kuznechno-shatampovochnoe proizvodstvo, 1989, No. 5, pp. 2-4.
Oliff & Berridg,e PLC
Sango Co. Ltd.
Tolan Ed
LandOfFree
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