US2675840A - Extension lever for ratchet bit braces - Google Patents

Description

April 0, 1954 o. c. DAIBER EXTENSION LEVER FOR RATCHET BIT BRACES Fild Feb.

OME G. DAIBER LIttomeg;

Patented Apr. 20, 1954 UNITED STATES PATENT OFFICE EXTENSION LEVER FOR RATCHET BIT BRACES Qme C. Daiber, Seattle, Wash. 7 Application February 23, 1949, Serial No. 77,753

2 Claims.

My present invention relates to boring tools and, more particularly, to an extension lever for ratchet bit braces.

My invention consists of providing an easily applied and secure extension lever for increasing the sweep or mechanical advantage of an ordinary carpenters brace, or bit-stock, and is particularly useful in the boring of large holes. The average carpenter, having a reasonably complete kit of tools, will usually have a brace of small sweep for use with the smaller diameter wood bits, and then a large sweep brace for use with the larger bits. However, there are many occasions when even the large sweep brace is not adequate to conveniently turn the ordinary wood bit of, say, one inch diameter in firm wood. Moreover, a carpenter is quite often required to drill holes considerably larger than one inch, and.

he normally will employ what is known as an expansion bit wherein an adjustable cutter can be set to cut the desired diameter up to, say, three inches, and the shank of the expansion bit is provided with the ordinary lead screw to cause the cutter to bite into the wood. When drilling such a large hole, considerable difficulty is experienced, and it is under such conditions that my extension lever, whichcan be quickly attached to the brace, gives a mechanical advantage of at least double that normally available in the normal sweep handle of the brace.

The principal object of my present invention, therefore, is to provide an extension handle for carpenter's bit braces.

A further object of my invention is to provide an extension handle for bit braces which greatly increases the mechanical advantage so that the effort of turning the brace will be greatly reduced.

A further object of my present invention is to provide an extension handle for boring braces that can be quickly secured in place without any separate clamps or other screw adjusted means.

A further object of my invention is to provide a brace extension lever which can be very cheaply constructed and can be sold at such low enough price that it will be generally available to workmen.

A further object of my invention is to provide a brace extension lever which is fabricated from sheet metal so that it will be light in weight and will be durable against breakage.

Further objects, advantages and capabilities will be apparent from the description and disclosure in the drawings, or may be comprehended or are inherent in the device.

In the drawings:

Figure 1 is an elevation showing a typical ratchet brace with my extension lever secured in operating position thereon.

Figure 2 is a fragmentary, perspective view showing the attaching end of my extension handle.

Figures 3 and 4 are cross-sectional views taken along respectively numbered lines on Figure 1.

Referring more particularly to the disclosure in the drawings, my extension handle consists of a gripping or clamping portion 10, a securing or positioning portion I2, and handle portion P5. The gripping portion I0 is illustrated in crosssection in Figure 4. It consists of a generally U- shaped member formed of sheet metal with the diameter of the curved portion of the U substantially the diameter of the brace stock with which it is to be used. This causes the U-shaped portion of my tool to rest securely upon the upper brace arm, as I4, and to be secured in a snapon relationship by a plurality of inwardly directed indentations, as I6 and [1. This portion of the tool, being U-shaped in form, is relatively strong, and it also is, therefore, well able to impart the turning efiort applied on handle IE to the brace itself.

In order to prevent longitudinal movement of clamp portion ID on the brace member I4, I have provided an outwardly extending arm, as 26, which terminates in a U-shaped stirrup member 22. This stirrup member is U-shaped and again has a diameter of curvature substantially the same as the stock 24 of the brace it is to be used with.

That portion of my extension handle that extends out beyond the brace handle 26, I prefer to form as a round or oval section, so that maximum pressure can be applied to it without either distorting the handle itself or causing undue pressure at any part of the workmans hand. Following this same plan, I prefer to slit the end of the tubular portion or handle thus formed in a plurality of slits 28, and then fold the metal over so that a smooth closed end 30 is obtained.

Method of use In using my extension lever on a carpenters brace, it is preferred to employ the type of brace having a ratchet mechanism, as at 32, to the end that the auger or drill bit can be turned by an oscillating movement of handle 26. It will be understood, of course, that the extension handle could be used on a fixed brace; however, it could not be employed to advantage. The handle is put in place on a brace by engaging stirrup member 22 on shank 2:5 with the clamp portion Ill of the extension handle substantially parallel to that portion, as l4, of the brac with which it is to be engaged. The clamp is then engaged with member M by a marked downward pressure as viewed in Figure 1. This will cause the U-shaped gripping or clamping member to straddle bar I4, and to be forced down so that indentations l6 and i? are below the center of bar M. In this way, a firm grip is obtained and the extension handle is worked in an oscillating movement. The ratchet 32, in effect, converts this intermittent action int-o rotary turning of the bit chuck and, thereby, to the bit held in the chuck.

Under certain conditions, it is desirable not to use stirrup 22 but to employ indentations as l8 so placed as to engage handle bar 21 or the curve at the junction of bar 2'! and the upper sweep bar It. This arrangement substitutes for stirrup 22, although not quite as effective in preventing longitudinal movement of the clamp member on bar i=2.

It is believed that it will be clearly apparent from the above description and the disclosure in the drawings that the invention comprehends a novel construction of an extension lever for ratchet bit braces.

Having thus disclosed the invention, I claim:

a 1. An extension handle for a carpenters brace,

comprising: a single sheet of metal bent to form a stirrup like arm at one end, a clamping intermediate section and a handle portion at the other end in integral connection, said intermediate section being elongated and of considerable extent and having an inverted U-shaped outline in transverse cross-section and said intermediate section having inwardly directed indentations in its sides forming projections on the inner side surfaces for engaging a brace upper sweep bar, positioned in said intermediate section, below its center and said sheet having sufficient resiliency to permit spreading of the sides of said intermediate section in insertion and removal of the sweep bar in a lateral direction, said stirrup, like arm being formed by an extension of said intermediate section directed upward therefrom at a sharp angle and terminating in an end are shaped and open towards one side of said handle adapted to clamp the stock of such brace with the lips of the are extending to the sides of the arc sufficient distance to abut the stock to prevent movement of the intermediate section longitudinally of the sweep bar; and said handle portion being formed with the sheet bent into an annular outline transverse cross-section with the edges of the sheet meeting on the underside of the handle and with the extreme end rounded.

2. An extension handle for a carpenters brace, comprising: a unitary metal body forming a stirrun like arm at one end, a clamping intermediate section and a handle portion at the other end, said intermediate section being elongated and of considerable extent and having an inverted U-shaped outline in transverse cross-section and said intermediate section having means for engaging a brace upper sweep bar, positioned in said intermediate section, below its center to secure the sweep bar against movement laterally of the intermediate section, said stirrup like arm being formed by an extension of said intermediate section directed upward therefrom at a sharp angle and terminating in an end are shaped and open. towards one side of said handle adapted to clamp the stock of such brace with the lips of the are extending to the sides of the arc sufiicient disto abut the stock to prevent movement of the intermediate section longitudinally of the sweep bar; and said handle portion being formed with an annular outline in transverse crosssection and with the extreme end rounded.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 89,925 Fray 1- day 11, 1869 1,744,413 Peterson et al Jan. 21, 1930 FOREIGN PATENTS Number Country Date 461,870 Great Britain Feb. 25, 1937 828,676 France Feb. 21, 1938

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