US 1310510 A
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Description (OCR text may contain errors)
c. A. SPE IRS.
APPLICATIQN FILED MAR. 27, l9l8.
Patented July 22, 1919.
| N v E N TO R Ufiarleafl/xazzderfiafs BYhzSATTORNEY UNITED STATES PATENT UFFIQE.
CHARLES A. SPEIRS, OF THE DARGLE, NATAL, SOUTH AFRICA,
Application filed March 27-, 1918.
To all whom it may concern:
Be it known that I, CHARLES ALEXANDER SPEIRS', of Killykeen, The Dargle, Natal, South Africa, have invented an Improved Screw-Extractor, and I do hereby declare the nature of this invention and in what manner the same is to be performed to be particularly described and ascertained inand by the following statement.
This invention relates to a device or instrument for extracting screws from wood or similar substances in which screws have been inserted and more particularly the class of round-headed screws employed in attaching corrugated zinc to the roofs and walls of buildings.
In practice it is often found that in adopting the usual meanssuch as a screwdriverof unscrewing or removing a screw in the circumstances above referred to, the screw has become so tight that the force employed breaks the head of the screw without effecting its removal.
By the use of my device or instrument greater force or grip can be used upon the head of the screw with better results than by the means ordinarily employed in removing screws in the circumstances I have re-- ferred to.
The invention consists in the method of enmploying the device or instrument as well as the construction thereof.
In the drawing Figure 1 is an ordinary-shaped pincers the jaws of which are so constructed as to inclose and grip the head of the screw.
The space is shown between the lips of the jaws, which when in operation is filled (or partially filled) by the shaft of the screwthe head being inside the jaws and not visible.
Fig. 2 is a similarly shaped pincers having the jaws b, bexpanded and open. The extremity of the jaws is each mouth-shaped; that is to say, space is made at a (jaw b), sufiicient so as to inclose, say, half of the head of the round-headed metal screws, such as are ordinarily used in attaching corrugated zinc to the roofs and walls of build- Specification of Letters Patent.
Patented July 22, 1919.
Serial No. 225,116.
ings. At d (jaw 19) a tongue or nib proects and is intended to engage the slot of the head of the screw when the head of the screw is gripped by the jaws and inclosed in the space or mouth 0. Both jaws are similarly constructed.
Fig. 3 represents the inside of one jaw of the pincers showing a half section of a metal screw with half its head in place in the mouth or space a, with the tongue or nib d in the slot of the screw head.
In operation the pincers are grasped, the lips of the jaws being inserted under the head of the screw so as to allow of the tongues or nibs engaging the slot of the screw head. The pincers are then more firmly grasped (or compressed) and turned in the opposite direction to that in which the screw was first inserted. The screw is promptly loosened; and the operation beingcontinued the screw is extracted.
Having now particularly described and ascertained the nature of my said invention and in what manner the same is to be performed, I declare that what I claim is 1. A screw extractor comprising a pair of pivoted jaws formed with recessed portions to receive a screw head, and nibs formed on said jaws for insertion within the slot of a screw head.
2. A screw extractor as claimed in claim 1 wherein the recessed portions are such as to provide lips which embrace the shank and head of a screw.
3. In combination, a pair of pincers comprising cross pivoted jaws formed with recessed portions on the working faces thereof to receive the head of a screw, and nibs projecting from the walls of said recessed portions for engagement with the slot in a screw head.
Dated at Pietermaritzburg this 29th day of November, 1917.
In witness whereof I have affixed my sig nature in presence of two witnesses.
G. A. SPEIRS. Witnesses:
ARTHUR G. LANGUAGE, W. G. HEDDING.
Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents,
' Washington, D. 0.