US3498351A - Screwdriver with screw-gripping jaws - Google Patents

Description

March 3; 1970 G. 2. EDWA RDS ETA 3,493,351

SCREWDRIVERWITH 'SCREW'GRIPPING JAWS m 9 1 L m e D d u 6 W H w w a w F LVE 5? 5 P a 2 b M M M M INVENTOR. GEORGE ZAHNOR EDWARD CAROLUS M. OSBORN ATTORNEYS United States Patent O US. Cl. 145-52 6 Claims ABSTRACT OF THE DISCLOSURE A screw-holding screwdriver of the type equipped with gripping jaws for holding screws during driving and removal thereof. Resilient gripping jaws have elongate flat strip extensions, whose ends are secured by means of a press fit between inner and outer collars encircling the shank of the screwdriver and arranged for limited sliding movement therealong. A cylindrical actuator tube slidably encircles the screwdriver shank and the jaw extensions for back and forth movement therealong. The jaw-actuating end of such tube is flattened to approximately elliptical formation for accommodating outwardly sloped portions of the jaws when forcing jaw contracting. A strip corresponding to but shorter than the jaw extensions and similarly mounted is outwardly turned and received as a stop by a keeper slot in the cylindrical end portion of the actuator tube for limiting movement of such tube in the direction of the gripping jaws.

BACKGROUND OF THE INVENTION Field The invention is concerned with a special type of screwdriver that utilizes gripping jaws to engage and securely hold screws of all kinds, especially Phillips head screws, so that they can be driven and removed at locations inaccessible to the hands, without danger of being dropped.

Problems of the art Many different constructions have been proposed heretofore for screwdrivers of this type, but for one reason or another none has met any significant commercial success. Some of these proposed constructions are complex and cannot be economically manufactured; others are difiicult to operate, or do not function satisfactorily.

SUMMARY OF THE INVENTION In accordance with the invention, an easily manufactured and very satisfactory construction is provided. Resilient gripping jaws have elongate flat strip extensions that reach along the shank of the screwdriver from outwardly bowed portions of the jaws adjacent the screwdriving tip to securement in a sliding collar encircling the screwdriver shank adjacent the handle. The collar is preferably composite, having an inner collar member against which ends of the extensions of the jaws are tightly held in a simple and effective manner by an outer collar member pressed onto the inner collar member.

A limit stop for the collar is provided on the screwdriver shank a predetermined distance along the length thereof toward the driving tip to control the location of the jaws in their gripping position.

Encircling the shank of the screwdriver and the fiat strip jaw extensions is a cylindrical tube, whose end por tion adjacent the driving tip is flattened to approximately elliptical form so as to accommodate outwardly sloped portions of the jaws as such jaws are forced closed about a screw head by movement of the tube toward the driving tip.

Although careful handling of this actuator tube will Patented Mar. 3, 1970 ice insure its complete retention on the screwdriver shank, it is preferred to provide a stop positively limiting the extent of movement of the tube toward the driving tip. This advantageously takes the form of a relatively short flat strip held in the composite collar as are the jaw extensions, and having its far end outwardly turned and extending into a keeper slot in the cylindrical end portion of the tube as a limit stop for such tube.

DESCRIPTION OF THE DRAWING There is shown in the accompanying drawing a screwdriver representing what is presently contemplated as the best mode of carrying out the invention.

In the drawing:

FIG. 1 is a view in side elevation of a Phillips-type screwdriver having screw-holding jaws in accordance with the invention;

FIG. 2, a fragmentary vertical section taken along the line 22 in FIG. 1;

FIG. 3, a view corresponding to that of FIG. 2, but showing the position of the parts when the jaws are in screw-holding position;

FIG. 4, an end elevation looking from the line 4-4, FIG. 2, and drawn to a larger scale;

I FIG. 5, a horizontal section taken on the line 5-5 of FIG. 2;

FIG. 6, an end elevation looking from the line 66, FIG. 3;

FIG. 7, a horizontal section taken on the line 7-7, FIG. 3, with a portion broken away for convenience of illustration;

FIG. 8, a horizontal section taken on the line 8-8, FIG. 3, and drawn to a scale larger than used for FIGS. 4-7;

FIG. 9, a fragmentary vertical section taken on the line 9-9 of FIG. 2; and

FIG. 10, a similar view taken on the line 1010 of FIG. 3.

DETAILED DESCRIPTION OF ILLUSTRATED EMBODIMENT In the form illustrated, a Phillips-type screwdriver, having a shank 12, driving tip 12a, and a handle 13, is provided with a pair of screw-gripping jaws 14, respectively, which have portions 14a sloping outwardly from flat strip extensions 15 that reach along the shank 12 to securement in a sliding collar 16 encircling the shank adjacent handle 13.

The jaws 14, including the outwardly sloping portions 14a'thereof, and the extensions 15 are advantageously bent to shape from elongate fiat strips of metal that are tempered to provide resiliency. The extensions 15 are conveniently and very eifectively secured to collar 16 by reason of the composite nature of such collar. Thus, the ends 15a of such extensions are merely interposed between inner and outer collar members 16a and 16b, respectively, and secured therebetween by pressing outer collar member 16b tightly against inner collar member 16a.

Collar 16 is adapted to be slid along shank 12 in the screw gripping and screw releasing operation of the screwdriver. Means for limiting its forward movement and the accompanying forward movement of jaws 14 along shank 12, see FIG. 3, is provided in the form of a protuberance 17 on such shank, formed, for example, either by upsetting the metal of the shank or by installing a pin thereinto. Backward movement is limited by screwdriver handle 13, see FIG. 2.

The jaws 14 are contracted about the head 18a of a screw 18, FIG. 3, by manually operating an actuator in the form of a cylindrical tube 19 mounted at one of its ends in a knob 20. The handle 13 and knob 20 are conveniently molded from plastic material, the handle being recessed at 21 to feceive a backwardly extending, reduced diameter portion 20a of the knob when the actuator tube 19 is pulled backwardly to open the jaws and release the screw, see FIG. 2.

In order to accommodate the outwardly sloped portions 14a of the jaws in the forward, jaw-contracting position of actuator tube 19, the opposite end portion 19a of such tube is flattened into substantially elliptical shape, FIGS. 4 and 5. This enables the jaws to be tightly held in screwgripping position, as shown in FIG. 3. Moreover, in order to properly grip the head of the screws, the jaws 14 should be curved outwardly from the portions 14a, respectively, j

and then back, as shown. This prevents camming action of the head of the screw.

In operation, the handle 13 is held by one hand of the user, and actuator tube 19 is operated either by the fingers of this same hand or of his other hand. For engaging a screw, knob 20 is pulled backwardly to its limit position, so the jaws 14 are retracted into fully open position, back from the driving tip 12a of the screwdriver, see FIG. 2. After the tip is positioned in the customary receiving recess of the screw, knob 20 is pushed forwardly to cause the elliptical end 19a of actuator tube 19 to engage the outwardly sloped portions 14a of jaws 14 and carry SllChJ. jaws forwardly until collar 16 contacts its limit stop 17, whereupon continued pushing of actuator tube 19 forwardly contracts jaws 14 about the head of the screw,

see FIG. 3. It should be noted that limit stop 17 is positioned at a location on shank 12 predetermined to place jaws 14 in advance of driving tip 12a just far enough to properly engage the underside of the head of the screw.

It is advantageous and preferred that means he provided to limit the forward movement of the actuator tube 19, so there will be no inadvertent disengagement of the actuating end 1911, of the tube from jaws 14 forwardly of driving tip 12a. A feature of the invention is that such means take the form of a flat resilient strip 22, FIGS. 7-10, of length predetermined by the maximum distance desirable for forward travel of the actuator tube 19, the forward end of which strip is turned outwardly as a stop member 22a for coaction with the closed, backwardly located end 23a of a keeper slot 23 formed in tube 19 and extending longitudinally thereof. Thus, as shown in FIG. 10, when knob 20 is pushed forwardly to an extreme position, stop member 22a is caught by the closed end 23a of keeper slot 23 and actuator tube 19 is prevented from sliding forwardly any further along screwdriver shank 12. v

It should be noted that, in the extreme forward position of knob 20, when jaws 14 are clamped about the head 18a of screw 18, see FIG. 3, such jaws clamp below the underside of and accommodate such head of the screw. This is made possible and is insured for any type of screwhead, whether the screw is of standard flat head type, as shown, of oval fillister type, round head type, etc., by reason of the fact that the previously mentioned, outward curve 14b, FIG. 2, of each jaw 14, commenses from a definite bend 14c and continues on outwardly and then inwardly to form a rounded concavity 14d. The forward terminal portion 142 of the jaw slopes forwardly from the curved or rounded portion 14b and terminates inwardly of the bend 14c.

Whereas this invention is here illustrated and described in detail from the standpoint of a presently preferred specific embodiment thereof, it is to be realized that various changes may be made within that generic preview of the disclosure without departing from the claimed subject matter.

We claim:

1. In combination with a screwdriver that includes a shank having a driving tip at one end and a handle at the opposite end, a screw-holding device comprising at least two mutually opposed, gripping jaws formed to engage the head of a screw with which the driving tip of the screwdriver is engaged;

said jaws having respective outwardly sloping portions and respective elongate, flat, strip extensions reaching along the shank of the screwdriver toward the handle thereof,

a sliding collar, made up of an inner and an outer collar member, to which ends of the jaw extensions are rigidly secured, said collar encircling the shank of the screwdriver for sliding movement therealong;

means for limiting movement of said collar toward said driving tip beyond a predetermined point; and

a jaw actuator in the form of a cylindrical tube mounted as a sleeve encircling the shank of the screwdriver and the extensions of the jaws and adapted for forward and backward sliding movement therealong to engage said outwardly sloping portions of the jaws and force them to contract the jaws about a screw, and to release said portions of the jaws to permit said jaws to open, respectively, the jaw-engaging end portion of said tube being flattened to substantially elliptical formation to accommodate said jaws.

2. A combination in accordance with claim 1, wherein the ends of the jaw extensions are rigidly secured between the inner collar member and the outer collar member by means of a press fit by said collar members.

3. A combination in accordance with claim 2, wherein there is additionally provided a flat strip of predetermined length shorter than the jaws as a limit stop to forward movement of the jaw actuator tube, an end of said strip being secured between the inner and outer collar members of the composite collar bythe press fit, and the opposite end of the strip being turned outwardly as a stop member; and a keeper slot in the cylindrical end portion of said tube for receiving and coacting with said stop member to limit forward movement of said tube.

4. A combination in accordance with claim 1, wherein the means for limiting movement of the collar toward the driving tip is a protuberance at a predetermined location on the shank of the screwdriver.

5. A combination in accordance with claim 1, additionally including means to limit the forward movement of the actuator tube.

- wardly to form a rounded concavity for accommodating the head of a screw, the forward terminal portion of the jaw sloping forwardly from the said concavity and terminating inwardly of the said bend.

References Cited UNITED STATES PATENTS 2,933,114 4/1960 Bystrom 52 FOREIGN PATENTS 526,935 9/ 1940 Great Britain.

ROBERT C. RIORDON, Primary Examiner ROSCOE V. PARKER, JR., Assistant Examiner

Images