US3675694A

US3675694A - Screw and screw driver combination

Info

Publication number: US3675694A
Application number: US106045A
Authority: US
Inventors: John W Barlow
Original assignee: Individual
Current assignee: Individual
Priority date: 1971-01-13
Filing date: 1971-01-13
Publication date: 1972-07-11
Anticipated expiration: 1989-07-11

Abstract

The disclosure relates to the combination with a screw of a screwdriver containing laterally extending keys on the shank thereof affording a flex coupling between the screw head and the screwdriver with the keys of the driver removably fitting keyways of the cone-shaped head of the screw during use and materially compensating for misalignment as well as eliminating the bouncing of the blade of the driver from the screw slot, thus requiring only minimum pressure to maintain positive coupling.

Description

United States Patent Barlow s] 3,675,694 July 11, 1972 [54] SCREW AND SCREW DRIVER COMBINATION [72] inventor: John W. Barlow, 263 Brighton Ave., San Francisco. Calif. 94129 [22] Filed: Jan. I3, 1971 [21] Appl. No.: 106,045

[52] U.S. Cl. 145/50 A, 85/45 [51 Int. Cl ..B25b 15/02 [58] Field of Search 145/50 A, 50 R; 85/45 [56] References Cited UNITED STATES PATENTS 172,351 l/1876 Sloan ..85/45 422,307 2/1890 Libbey.. ....14$/50 A 2.258.326 10/1941 Holt [45/50 A FOREIGN PATENTS OR APPLICATIONS 1.027.698 4/1966 Great Britain ..8S/45 [/1964 Canada 145/50 A 1/1911 Switzerland "145/50 R Primary Examiner-Robert C. Riordon Assistant ExaminerRoscoe V. Parker. Jr. A!!orne \-Arlington C. White 57 ABSTRACT The disclosure relates to the combination with a screw of a screwdriver containing laterally extending keys on the shank thereof affording a flex coupling between the screw head and the screwdriver with the keys of the driver removahly fitting keyivays of the cone-shaped head of the screw during use and materially compensating for misalignment as well as eliminating the bouncing of the blade of the driver from the screw slot. thus requiring only minimum pressure to maintain positive coupling.

3Clailns,6 Drawing Flgures SCREW AND SCREW DRIVER COMBINATION Considerable attention has heretofore been devoted to the development of improved screws and screwdrivers, and a number of patents have issued therefor. Among these are US. Let. Pat. No. 1,476,653, directed to the formation of beveled surfaces upon opposite faces of the blade of a screwdriver for engaging a correspondingly shaped nick or slot in the head of the screw; US. Pat. No. 1,797,390 discloses a tapered blade on the screw driver to provide strength to the blade yet allowing its working edge to be visible for facilitating its entry into the kerf of the screw, with a provided key on the bit entering a key-hole formed in the screw; US. Pat. No. 2,160,244 discloses a specially formed screwhead defining a socket to be engaged by a corresponding tapered body portion on the bit of the driver serving to guide and hold the driver securely centered in the screw recess; US. Pat. No. 3 ,044,5 l3 provides for a centrally disposed hole in the center of the slot of the screw head. While many of these different types of screw drivers and screws have entered the market, they have not met with great use because of the many disadvantages in the combinations, principally in their tendencies to bounce apart while in endeavoring to drive the screw home to operative position, as well as while endeavoring to remove the screw. This particular disadvantage causes others, such as ruining the slot in the screw, damage to the bit of the screwdriver and frequently injuries to the users. In many cases, the screws have been damaged beyond effective use and must be replaced, and also the screwdriver. In some cases, when attempting to remove prior types of screws, the surrounding portions of the work has splintered or become otherwise damaged requiring costly replacements. The present invention is directed to the provision of a uniquely constructed screwdriver for engaging by flex coupling therewith a specially form screw whereby a combination is provided which obviates all of the disadvantages of prior screw driver and screw combinations and which does the job more effectively and more expeditiously.

A primary object of my invention is to provide a screw and screwdriver combination which affords a flex coupling throughout 360 between the screw and driver when in use. Another important object of the present invention is to provide a screw and screwdriver combination of the indicated nature which is additionally characterized by an increased strength in the flex coupling between the units in operation and the capability of the connected units to maintain a steady pressure at the center of the screw head without bounce or slip-out or displacement of the driver in respect to the screw.

A still further object of my present invention is to provide an improved screw and screwdriver combination of the aforementioned character wherein the uniquely constructed screw driver can be fitted and secured to the screw head during operation thereof for the entire period in driving the screw home as well as removing the same from the work.

A further object of the invention is to provide an improved screw and screwdriver which in use and engagement with one another reduces to a minimum the destructive effects of misalignment, not accomplished in any other screw and screwdriver combination heretofore.

A still further object is to provide a screw of improved construction which is appreciably more efl'ective functionally with any or standard screwdriver.

Other objects of the invention, together with some of the advantageous features thereof, will appear from the following description of the best mode contemplated by me of carrying out the invention and the manner of making and using the same, as evidenced by an embodiment thereof illustrated in the accompanying drawings. It is to be understood that variations of such embodiment are included in the claims appended hereto. Referring to the drawings:

FIG. I is a perspective view of the screwdriver component of a preferred embodiment of the invention.

FIG. 2 is a fragmentary sectional side elevational view of the embodiment of FIG. 1 taken on the 2-2 thereof and illustrating the bit of the specially constructed blade of the driver.

FIG. 3 is a fragmentary edge sectional elevational view, taken on the line 33 of FIG. I.

FIG. 4 is a perspective view of the screw component of the preferred embodiment of the invention.

FIG. 5 is a front elevational view, partly in section, of the embodiment of screw component shown in FIG. 4, taken on the line 5-5 of FIG. 4.

FIG. 6 is sectional detail taken on the line 6-6 of FIG. 5. In its best mode, the combination screwdriver and screw of my present invention preferably comprises a pair of laterally extending keys on the blade of a screwdriver disposed in opposed relation to one another on opposite sides of the blade, said keys being coextensive in length with the blade, together with an engageable screw formed with a cone-shaped base having a cross-slot in the head thereof for receiving the bit of the blade of the screwdriver as well as having keyways extending laterally from the longitudinal center of said cross-slot and in opposed relation to one another; the bottoms of said keyways and the bottom of said cross-slot tapering from the apex of the cone base on said head of said screw toward the outer ends of said keyways and said cross-slot.

In accordance with my invention, I provide a screwdriver which is generally designated by the reference numeral ll and which includes a handle 12 of generally cylindrical shape but preferably tapering toward its outer extremity, and also includes a blade 13 preferably formed or cast integrally with the handle 12 and which terminates at its outer extremity with a straight bit 14 of predetermined width for engaging the kerf of a screw. The blade 13 of the screwdriver 11 is so fashioned as to provide thereon a pair of keys l6 and 17, which, as shown, extend laterally on opposite sides of the blade and longitudinally of the blade 13 from the bit 14 to the handle 12. Preferably, the keys I6 and 17 are arranged on the blade 1 3 so as to oppose one another midway of the length of the bit 14 or width of the blade. The screwdriver II, in its entirety, can be cast from a suitable spring steel or steel alloy stock to insure life-time durability since it is re-sharpenable, or the handle 12 thereof can be fabricated from a hard wood, or from plastic material and press-fitted or otherwise permanently secured to the blade 13. The provision of the keys l6 and 17 on the blade lends great strength thereto and this resists distortion or snapping apart upon the application of external force, such as from the driven shaft of a motor to which it may be detachably connected.

As particularly illustrated in FIGS. 4 and 5 of the annexed drawings, I provide a specially formed screw 2I for cooperation with the uniquely constructed screw holder 11 in fastening elements of a work together, both not shown, as well as for loosening the screw and removing the same from the work, when desired. The screw 2] comprises a shallow cone base 22 which merges into a threaded shank 23 of conventional form consisting of a cylinder of wood or metal having a helical ridge winding around it. While a wood screw is illustrated with standard tapering spiral thread, the shank 23 can be so threaded as to provide a metal screw for holding metal parts together. In addition to the customary cross-slot 24 in a circular top with circumferential rim 25 which cross-slot 24 is of greater depth adjacent to the rim 25 than prior screw slots because of the tapering of the slot in conformity with the cone base 22, I provide in the head of the base 22 a pair of opposed key-

ways

26 and 27 which extend from approximately the longitudinal center of cross-slot 24 and from opposite sides of such crossslot. Preferably, and as hereinabove stated, the body of the head 22 of the screw 21 is formed in the shape of a shallow cone with its apex 28 at the center of the cross-slot, considered longitudinally and transversely. The shallow cone construction of the head 22 of the screw results in a tapering of one-half of the bottom of the cross-slot 24 from the center thereof or apex 28 of the shallow cone in one direction to and through the perimeter 25 of the top of the head, as well as a tapering of the bottom of cross-slot 24 in the opposite direction to and through the perimeter 25 at a diametrically opposite point from the bottom one-half of cross-slot 24 above mentioned. Similarly, the cone-shaped head 22 provides for a tapering of the bottoms of each of the

keyways

26 and 27 from the apex 28 of the shallow cone head to the end wall of each keyway;

such keyways

26 and 27 merging said cr'ris-slot'i 'tenddib be included in the appended claims.

at their inner ends.

This construction of the head 22 of my improved screw 21 afl'ords, when the screwdriver is engaged with the screw, a flex coupling therebetween so that throughout a 360 turning of the screwdriver 1 l in driving the screw 21 home into the work as well as in removing the screw from the work there is no likelihood of the screwdriver bouncing out of the cross-slot 24 or out of the

keyways

26 and 27 as there is virtually a locking of the straight bit 14 of the blade [3 of the driver as well as the

keys

16 and 17 thereon with, respectively, the cross-slot 24 of the screw and the

keyways

26 and 27 thereof, even allowing for the usual tilting of the screwdriver in respect to the screw during these operations of fastening and unfastening of the screw: into and from the work. Moreover, by virtue of the cooperative interfitting between the bit of the screwdriver It and the cross-slot of kerf 24 of the screw 21, which cross-slot is of sufficient depth to receive the bit 14, as well as between the keys to and 17 of the screwdriver and the

keyways

26 and 27 of the screw head 22, which likewise of sufficient depth and dimensions to receive the keys l6 and 17 of the driver 11, the likelihood of misaligning the two components, that is, the screw and screwdriver, when driving a screw home or unfastening the same, is reduced to a minimum. It seems evident, also, that there is little likelihood of tearing of the side walls of the cross-slot 24 or of the

keyways

26 and 27 during turning operations through the complete turning circle, thus prevention of damage to screws and screwdriver is virtually eliminated and losses in the stocks of screws are avoided.

It is to be understood that variations in shapes of the keys on the screwdriver and the keyways in the screw head are inlclaim:

l. A screw and screwdriver combination for flex coupling with one another to detachably secure portions of a work together; said screw comprising a head having a cross-slot therein, a cone-shaped base integral with and underlying said head with the apex of said cone at the longitudinal center of said cross-slot and with the bottom of said cross-slot tapering outwardly in opposite directions from the apex of said coneshaped base, and a pair of keyways in said base extending outwardly from opposite sides of said cross-slot with their bottoms tapering outwardly therefrom; said cross-slot and said keyways being adapted to removably receive a screwdriver comprising a handle, a blade on said handle, a bit on the outer extremity of said blade for removably fitting said cross-slot of said screw and engagingly rotating the same, and a pair of keys on opposite sides of said blade for removably seating in said keyways of said screw to effect a flex coupling therewith during rotation of said screw in driving the same into the work and removing the screw from the work.

2. A screw and screwdriver combination as set forth in claim I wherein said cross-slot of said screw crests at the longitudinal and transverse center thereof as the apex of the cone of said cone-shaped base for tiltably receiving and holding the bit of said screw-holder.

3. A screw and screwdriver combination as set forth in claim 1 wherein said keys on said blade of said screwdriver are flex coupled with said keyways and applied pressure of said screwdriver onto said screw is upon said cross-slot of said screw at the apex of said cone-shaped base.

Claims

1. A screw and screwdriver combination for flex coupling with one another to detachably secure portions of a work together; said screw comprising a head having a cross-slot therein, a coneshaped base integral with and underlying said head with the apex of said cone at the longitudinal center of said cross-slot and with the bottom of said cross-slot tapering outwardly in opposite directions from the apex of said cone-shaped base, and a pair of keyways in said base extending outwardly from opposite sides of said cross-slot with their bottoms tapering outwardly therefrom; said cross-slot and said keyways being adapted to removably receive a screwdriver comprising a handle, a blade on said handle, a bit on the outer extremity of said blade for removably fitting said cross-slot of said screw and engagingly rotating the same, and a pair of keys on opposite sides of said blade for removably seating in said keyways of said screw to effect a flex coupling therewith during rotation of said screw in driving the same into the work and removing the screw from the work.

2. A screw and screwdriver combination as set forth in claim 1 wherein said cross-slot of said screw crests at the longitudinal and transverse center thereof as the apex of the cone of said cone-shaped base for tiltably receiving and holding the bit of said screw-holder.