Patent TW-434120-B (TW)
Title: Improved auto-adjusting pliers
Inventor: KHACHATOORIAN ZAREH
IPC: B25B7/10
Filed: 1999-12-24
Granted: 2001-05-16
Abstract: An improved auto-adjusting pliers for automatically adjusting for different sized work pieces includes a first elongate member having a fixed jaw at one end, first elongate handle at the other end and a first neck portion between the fixed jaw and the first handle. A second elongate handle is provided which has one end pivotally connected on the fixed jaw for pivotal movements between a normally open or releasing position and a closed or gripping position. A second elongate member is provided which has a movable jaw at one end arranged in substantial opposition to the fixed jaw and which has another end mounted on the second elongate handle for movements responsive to pivoting movements of the second elongate handle relative to the fixed jaw for primarily adjusting the spacing between the jaw. A second neck portion is provided between the movable jaw and the other end of the second elongate member. An elongate link has one end pivotally mounted on the second neck portion and the other end mounted for both pivotal and linear movements on the first elongate handle responsive to movements of the second elongate member relative to the first elongate member. Slots or channels are provided on the first neck portion at one or both ends of the link and on said second handle to allow pivot pins slidably arranged within such slots to move linearly therein between the initial and extended positions. The stop pin in the slot or channel on the first neck portion selectively terminating continued generally linear movements of the stop pin along the first guide means following engagement of a work by the jaws, the stop pin limiting continued relative movements of the second elongate member to pivoting movements of such member relative to said first elongate member. Springs are provided between the second handle and the first neck portion for urging the handles to normally separate when no gripping forces are applied to the handles and for urging and normally maintaining the other end of the link in the initial position prior to engagement of a work by the jaws. The movable jaw is arranged to substantially linearly advance towards the fixed jaw prior to gripping of a work by the jaws. Gripping of a work between the jaws causes said stop pin to convert further closure of handles to relative pivoting movements between the neck portions and jaws determined by the size of the work and causes the jaws to move to substantially parallel orientations to linearly compensating movements of the other end of the link and second elongate member from the initial positions towards the extended positions along the second and third guide slots or channels against the biasing forces of the springs. Alternate embodiments are disclosed in which two or three degrees of freedom of linear movements are available to the operative parts of the pliers after the work has been gripped by the jaws, such movements being made possible by pins mounted in elongate slots or channels within the first handle, the second handle and/or the elongate link itself.