US2423296A - Screw driver - Google Patents

Description

y 1947- T. D. CRAWFORD 2,423,295

SCREW DRIVER Filed June 8, 1944 1 .2 By] F 2; I /0 a 8 /4 7 g 5 I 4 4 -11 I Tlmmasl). ('rdnford INVENTOR.

HIS AGENT.

2 Sheets-Sheet 1 July 1, 1947 T. CRAWFORD S CREW DRIVER 2 Sheets-Sheet 2 Filed June 8 1944 INVENTOR.

BY I

HISAGENTI Patented July 1, 1947 UNITED STAT ES FATE N T O F F l C E 'SGREW DRIVER Thomas D. Grawford, Wichita Falls, Tex. Application June 8, 1944, Serial No. 539,328

.3 Claims.

This invention relates to improvements in screw drivers.

Since screws are manufactured with slots of different sizes and shapes, heretofore it has been necessary-for a mechanic to have two or more screw drivers in order to accommodate various types of screws. This is annoying and has ac counted for much loss of time in locating the proper screw driver for the proper screw; and, when working in inaccessible places or cramped quarters, such as the fuselage of an airplane, it might be necessary even for the workman to get out of the plane, or at least out of working position, to obtain the proper screw driver for the operation.

The object of this invention is to improve the construction of the screw driver to adapt it to fit difierent types or sizes of screws; that'is readily adjustable to accommodate the respective screws; that operates on the screw in axial alignment with the handle, so as to enable the mechanic to apply pressure to a point directly above the screw; and which is simple in construction and inexpensive to manufacture.

In the preferred form of the present invention, the screw driver fits twocommon types of screws, and is readily accessible for either type merely by flipping one or the other of'the blades intooperating position. The auxiliary blade is shown as adaptable to fit'a screw known as the Phillips-head screw, but it is understood that this auxiliary blade may be so formed as to fit other types of screws, such as the Allen head, Bristo, or other types or sizes of screws or bolts. use with the'sarne screw driver handle and usual blade.

Different embodiments of this invention are illustrated in the accompanying drawings, in which:

Fi 1 is a side elevation of one form of the invention, showing a,-Ph-i1lipS-he'ad screw driver blade in position for operation;

Fig. 2 is a view similar to Fig. 1 but taken at right angles thereto;

Fig. 3 is a side elevation ofthe auxiliary'blade removedfrom the usual screwdriver;

Fig. 4 is a toprplan view ofrthe-auxiliary blade;

Fig... 5 is a cross-section through the screw driver;

Fig. '6 is a side'elevation of a screw driver showing a. modified form of "accessory; and

Fig. 7 is a view similar to Fig. 6 but taken at right angles thereto.

Referring more in detail to the drawings, the

A variety of. blades may be provided for numeral l indicates a handle of the usual character in which is secured one end of a shank 2. The shank 2 is elongated and preferably rectangular in cross-section. The opposite end of the shank 2 is formed with the usual bla'de3, somewhat wedge-shaped for engaging the usual screw slots;

The shank 2 has a hole therethrough intermediate the ends thereof to receive a bolt 4 which is provided-with a wing nut 5 thereon. A bowed leaf spring 6 is provided under the wing nut 5 so as to apply endwise tension to the bolt. The spring fi has prongs on one end thereof to engage in recesses 8 in the adjacent side of the shank 2, so as to hold the spring against endwise displacement relative to the shank.

Pivotally mounted on the bolt 4 is a secondary screw driver member 9, one end of which has a hole therein receiving the bolt 4 to form a pivotal connection therewith, while the opposite end portion is' formed with a screw driver head In, the end I l thereof'being substantially in the shape of across, as shown in Fig; 4, to fit in Phillips-type screws having crossed slots. The shank portion of the secondary blade 9 is disposed in abutting relation-against a side of the shank 2, while the head portion l'il thereof is off-set from the shank of the'bl'ade 9 in position'for axial alignment with the major portion of the length of the shank 2 when -the secondary bladeis in theposition shown in full lines in Fig1 2. The secondary blade 9 is formed in the oiT-set portion thereof with a bifurcation l2'to receive therein and embrace the blade 3, being substant-i'a-ll'y wedge-shaped for that purpose, so as to term a dri'vingconnection between the shank 2 andthe head 10 of the secondary blade. This bifurcation fits closely about three sides and at the end of the main blade 3 of the screw driver. This relation, together with the axial alignment of 'the head 'liIl' with the major portionof the shank '2, causes a substantial amount of torque to bettansniitteddire'ctly by'the blade 3 to the head It]; thereby relieving the bolt 4 of substantially all strain.

The loose fitting of the bolt 4 and nut 5 makes it possible for the secondary blade 9 to be moved laterally, as indicated" in dotted lines in Fig. 2, away from interengagementwith the blade 3,

thereby permitting pivotal swinging movement on the bolt 4 to the lower dotted line position therein; In the latter position, the'h'e'ad l0 fits in a, recess 13 formed at one side of the shank 2 by an 01f -set in said shank intermediate the handle l and the bolt 4. In this position, the secondary blade 9 is substantially confined relative to the shank 2 not only to expose the blade 3 but also to permit use of the latter for conventional screws.

The secondary blade 9 carries a stop member, such as a ball I4, at the inner side thereof in position to engage a recess I5 at the outer face of the shank 2 on one side of the bolt 4 or a corresponding recess l 6 therein at the opposite sid of said bolt, to hold the secondary blade in fixed positions relative to the shank '2 of the screw driver either in the full line position or in the lower dotted line position indicated in Fig. 2.

It will be appreciated that the secondary blade 9 can be moved quickly and readily from one position to another either to expose for use the conventional screw driver blade 3 or to locate the Phillips-type head H1 in operative position. Thus, an operator can change from one type of screw to another without loss of time and in a simple and effective manner, using the one screw driver for both types.

A modification of this construction is shown in Figs. 6 and '7, in which the handle 2! having a shank 22, has the usual screw driver blade 23, all substantially as described above. However, in this form, the bolt 24 is turned at right angles with respect to its position in Figs. 1 and 2, so as to extend parallel with the edge of the blade 23.

The secondary blad 29 pivotally mounted on they bolt 24 has a bifurcation 32 formed as a recess in a, side thereof in position to receive and fit over the edge of the screw driver blade 23 in close relation therewith. This relation enables the blade 23 to fit more closely into the recess in th secondary blade 29. The secondary blade 29 is shown as provided with the usual Phillips-type screw driver head 30 thereon.

The manner of use of the form of the invention shown in Figs. 6 and '7 is the same as that described above in connection with Figs. 1 and 2. The bolt 24 will slide sufiiciently to allow the sec ondary blade 29 to clear the screw driver blade '23, as shown in the upper dotted line position in Fig. 7. Then the secondary blade can be moved to the lower dotted line position therein, exposing the usual screw driver blade for use. The secondary blade can be moved from one position to another readily and simply, whenever desired. When in the position shown in full lines in Fig. '7, th interfitting connection at the recess 32 insures that substantially all of the torque from the shank 22 will b transmitted to the secondary blad 29 without undue strain on the bolt 24.

Although the invention is shown with a Phillips-type screw driver head on the secondary blade, the form of this may be changed as desired to other forms or sizes of screw connections or other tools, as will be appreciated.

I claim:

1. A screw driver comprising an elongated shank having a screw driver blade on the outer end thereof, said shank having a portion thereof bodily offset intermediate the length of the shank forming a recess in one side of the shank, a secondary blade arranged in side-by-side relation against said side of the shank, means pivotally mounting said secondary blade on the shank for swinging movement, about an axis extending transversely through the shank, to difierent positions with respect thereto, said secondary blade having an offset end portion in position to engage the screw driver blade in longitudinal alignment therewith in one position of the secondary blade and to be disposed in the recess of the shank when moved about its pivot axis to the opposite position with respect thereto.

2. A screw driver comprising an elongated shank having a screw driver blade on the outer end thereof, said shank having a portion thereof bodily offset intermediate the length of the shank forming a recess in one side of the shank, a secondary blade arranged in side-by-side relation against said side of the shank, means pivotally mounting said secondary blade on the shank for swinging movement, about an axis extending transversely through the shank, to different positions with respect thereto, said secondary blade having an ofiset end portion in position to engage the screw driver blade in longitudinal alignment therewith in one position of the secondary blade and to be disposed in the recess of the shank when moved about its pivot axis to the opposite position with respect thereto, said pivotal means including loose mounting means, and a yieldable connection with the shank permitting axial yielding of the secondary blade in swinging between said respective extreme positions.

A tool of the character described comprising a shank having a screw-driver blade thereon integral therewith, a secondary screw-engaging element beside the shank and having screw-engaging means thereon, said secondary element being adapted to be moved from a position beside the shank with the screw-engaging means spaced from the screw-driver blade to a position beside the blade with said means in axial alignment with the blade, means on the element in position to embrace the screw-driver blade when the screwengaging means is in axial alignment with the blade, and means mounting said secondary element on the shank including a bolt pivotally connecting the element with the shank, and a spring connected with the bolt and yieldably holding the element against the shank, said bolt and spring coacting to form yieldable connection between the secondary element and the shank for swinging movement of said element substantially in the plane of the longitudinal axis of the bolt during movement of the embracing means into and out of embracing relation with th blade and for rotating movement in a, plane substantially at right angles to the axis of the bolt during movement of the element into and out of side-by-side relation with the blade.

THOMAS D. CRAWFORD.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 981,278 Jenks Jan. 10, 1911 385,791 Carpenter July 10, 1888 393,288 Barber Nov. 20, 1888 1,436,040 Hoddinott Nov. 21, 1922 2,242,873 Thompson May 20, 1941 152,198 \Vakefield June 16, 1874 FOREIGN PATENTS Number Country Date 39,819 Sweden Nov. 12, 1914 109,670 Great Britain Sept. 27, 1917

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