EP 0421144 A3 19911009 - EXPANDING TOOL
Title (en)
EXPANDING TOOL
Publication
Application
Priority
DE 3933293 A 19891005
Abstract (en)
[origin: EP0421144A2] The invention relates to an expanding tool for a shaping device, in particular a forging die, for the production of hollow workpieces, having a ram and an expanding sleeve which accommodates the free end portion of the latter positively in a location opening, consists of radially movable segments separated by parting seams and the outer contour of which corresponds to the inner contour of the workpiece, the parting seams being formed by mutually adjoining boundary surfaces of adjacent segments. In known expanding tools, the segments are separated from one another by radially extending parting seams which widen when the expanding sleeve is expanded, with the result that plastic or molten workpiece material can penetrate during the shaping operation. In order to prevent an increase in the width of the parting seams between the segments during the expansion of the expanding sleeve, an even number of at least four segments is provided according to the invention, the planes of the parting seams extending outside the longitudinal centre axis of the expanding sleeve (2) such that, with the expanding sleeve (2) expanded, the parting seams are closed in the region of their outer contour. <IMAGE>
IPC 1-7
IPC 8 full level
B21J 5/12 (2006.01); B21J 13/02 (2006.01); B21K 1/76 (2006.01)
CPC (source: EP)
B21J 13/025 (2013.01); B21K 1/762 (2013.01); B21K 1/765 (2013.01)
Citation (search report)
- [X] GB 2129354 A 19840516 - PFD LTD
- [XP] EP 0358784 A1 19900321 - AIDA ENG LTD [JP]
- [X] WO 8701061 A1 19870226 - PFD LTD [GB]
- [X] EP 0153810 A1 19850904 - PFD LTD [GB]
- [A] GB 2203076 A 19881012 - LOEHR & BROMKAMP GMBH
- [A] EP 0049474 A1 19820414 - NISSAN MOTOR [JP]
- [X] PATENT ABSTRACTS OF JAPAN, Band 7, Nr. 25 (M-190)[1170], 2. Februar 1983; & JP-A-57 181 737 (AIDA ENGINEERING K.K.) 09-11-1982
Designated contracting state (EPC)
DE ES FR GB IT
DOCDB simple family (publication)
EP 0421144 A2 19910410; EP 0421144 A3 19911009; DE 3933293 A1 19910411; JP H03133535 A 19910606
DOCDB simple family (application)
EP 90117223 A 19900906; DE 3933293 A 19891005; JP 26618590 A 19901003