US420431A - Island - Google Patents

Description

(No Model.)

M. J. BARTLETT. ATTACHMENT FOR SCREW DRIVERS.

Patented Feb.4,1890.

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UNITED STATES PATENT, @FFICE.

MARCUS J. BARTLETT, OF PROVIDENCE, RHODE ISLAND.

ATTACHMENT FOR SCREW-DRIVERS.

SPECIFICATION forming part of Letters Patent No. 420,431, dated February 4, 1890.

Serial No. 306,191. (No model.)

To all whom it may concern.-

Be it knownthat I, MARCUS J. BARTLETT, a citizen of the United States, residing at Providence, in the county of Providence and State of Rhode Island, have invented certain new and useful Improvements in Attachments for Screw-Drivers; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same, reference being had to the accompanying drawings, and to letters of reference marked thereon, which form a part of this specification.

The object of my present invention is to provide screw-drivers with mechanical means whereby a screw may be held in position while being driven.

To that end my invention consists, essentially, of an attachment adapted to be secured to the blade of a screw-driver and hav ing a downwardly-extending spring-arm arranged when in use to engage with the side of the screw-head.

By means of myimprovement screws, particularly small machine-screws, may be held and inserted as readily as screws of large size.

In the annexed drawings, Figure l repre- 'sents a side elevation of an ordinary screwdriver provided with my improvement as in use. Fig. 2 is a perspective view of the device detached. Fig. 3 is a cross-sectional View taken on line w 00 of Fig. 1, and Fig. 4 is a similar view showing a larger screw-driverextends downwardly and is provided at its lower end, on the inner side, with a concave face 1), adapted to bear against the side of a screw-head n. The frame portion a is made somewhat long, thereby when in use preventing the free end of the arm I) from accidental displacement.

The manner of its application and use is clearly represented in Fig. 1. The extension 5' 5 h, by reason of its engagement with the screw-head, acts to maintain the screw in a vertical position-that is to say, the end tof the blade is inserted into the nick n, the curved portion b of the spring-armbearing against one side of the head. WVhen the screw is thus frictionally held, it is obvious that it may be readily carried without fear of losing it.

Another advantage is that in driving the screw the point of the blade is automatically held in the screw-slot until the screw is fully inserted.

My invention is particularly adapted for the use of watch and clock makers, and also for makers and repairers of light tools and machinery. The construction is such that the implement maybe quickly detached from the driver and, if desired, applied to another driver-shank having a different size. It is obvious that the form of the end I) of the spring-arm may be made to conform to any shape of the screw-head without departing from the spirit of the invention.

I do not claim, broadly, means for holding a screw while it is being driven; but

TVhat I do claim, and desire to secure by United States Letters Patent, is-- 1. The attachment for screw-drivers, consisting of a head or frame portion provided with an enlarged opening to receive various sizes of screw-driver blades, a screw or clamp for securing the frame to the blade, a springarm secured to. the under side of the frame and having the inner face of the arm at its lower end adapted to frictionally engage a portion of the peripheral surface of a screwhead, substantially as shown and hereinbefore described.

2. The combination, with a screw-driver 9 blade, of the screw-driver attachment hereinbefore described, consisting of the head or frame portion a, through which the blade freely passes, a screw 0, tapped into said In testimony whereoflhave effixedmysigframe andbearing against the blade, aspringnature in presence of two Witnesses.

arm extending from the under side of the frame and having the inner face of the arm MARCUS J. BARTLETT. at its lower end adapted to frictionelly engage a portion of the peripheral surface of Witnesses:

a screw-head, substantially as shown and set CHARLES I-IANNIGAN,

forth. GEO. H. REMINGTON.

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