Patent 1,156,739 · Backus's Locking Clamp · Page 3

It is thus possible to press the jaws together so as to clamp articles of different sizes within the capacity of the clamp. When it is required to obtain the article the key 12 is introduced into the key space and pressed home therein, thereby operating the dogs 9 and moving their toothed ends away from the toothed edges of the segments 4 with the result that the pivoted jaw is released and instantly and automatically flies open under the action of the spring 22 in the manner stated.     Having thus described the invention, what is claimed as new is:--     1. A clamp comprising pivoted jaws, a key operated locking mechanism for holding the jaws against spreading from either one of a plurality of positions, and a guard comprising projecting parts one of such parts normally obstructing the access to the locking mechanism and the remaining projecting part being inclined to ride upon the proper key and admit of the obstructing part being withdrawn from the path of the key when introducing the same into the lock to effect release of the jaws.     2. A clamp comprising pivoted jaws, the pivotal end of the jaws forming opposed inclosing walls, upper and lower plates closing the space formed between the side walls to form a case and a key operated locking mechanism disposed within such case and adapted to prevent spreading of the jaws from either one of a plurality of positions.     3. A clamp comprising a fixed jaw having spaced side wings at one end, a pivoted jaw having toothed segments at one end which are disposed with the wings of the fixed jaw, locking dogs carried by the fixed jaw and adapted to engage the toothed segments to hold the jaws against spreading from either one of a plurality of positions, and a key for effecting simultaneous release of the locking dogs from the toothed segments.     4. A clamp comprising a fixed jaw having transversely spaced wings, a pivoted jaw provided with transversely spaced toothed segments arranged to lie against the inner faces of the said wings, a partition disposed within the space formed between the front and rear walls comprised between the pivotal ends of the jaws and forming a key-space, and locking means adapted to contact with the toothed segments and adapted to be actuated by a key inserted in the said key space.     5. A clamp comprising pivoted jaws having their pivotal ends spaced apart, a toothed segment upon one of the jaws, a partition disposed in the space formed between the pivoted ends of the jaws to form a key-space, a locking device arranged to

coact with the toothed segment to prevent spreading of the jaws from either one of a plurality of positions, and a guard adapted to normally obstruct the key-passage to the locking device and adapted to be actuated by the proper key when inserted for effecting release of the locking device.     6. A clamp comprising pivoted jaws having their pivotal ends spaced apart, a toothed segment upon one of the jaws, a partition disposed between the pivotal ends of the jaws and forming a key space, a locking device disposed to coact with the toothed segment and releasable by means of a key, and a guard mounted upon the partition and having projecting portions, one obstructing entrance to the locking device and the other adapted to be engaged by the key to withdraw the key obstructing projection from the path of the key when introduced to effect release of the locking device.     7. A clamp comprising a fixed jaw, a pivoted jaw provided with transversely spaced toothed segments, a partition disposed between the pivotal ends of the jaw to form a key space, dogs arranged to coact with the toothed segment and having portions extending across the key space, and a guard having projecting portions normally obstructing entrance to the dogs and adapted to be actuated by the proper key to effect withdrawal of the obstructing parts from the passage of the key when introducing to effect release of the dogs from the toothed segments.     8. A clamp comprising pivoted jaws, toothed segments upon one of the jaws, a partition arranged between the pivotal ends of the jaws and forming a key-space and having a projection, key operated dogs disposed upon opposite sides of the projection of the partition and disposed to coact with the toothed segments, and a flat spring supported by the projection of the partition and having its ends engaging the said dogs.     9. A clamp comprising pivoted jaws, transversely spaced toothed segments upon one of the jaws, pivoted dogs disposed to coact with the toothed segments and formed with stop shoulders, a partition disposed between the pivotal ends of the jaws and inclosing a key space and formed with a projection, and a flat spring supported between its ends upon the projection of the partition and having its ends engaging the dogs and abutting against the stop shoulders thereof.     10. A clamp comprising a fixed jaw having transversely spaced wings, a pivoted jaw closing the space formed between the wings of the fixed jaw and formed with toothed segments which are disposed to lie against the inner faces of the said wings, upper and lower plates closing the space between the wings above and below the toothed segments, a partition arranged within the