US3003528A - Screw-holding screw driver - Google Patents

Description

Oct. 10, 1961 "w. E. LANDEAU 3,003,

' SCREW-HOLDING SCREW DRIVER Filed June 22, 1959 INVENTORI WARNER E; LANDEAU I B Y I ATTORNEY 3,003,528 SCREW-HOLDING SCREW DRIVER Warner E. Landeau, Racine, Wis. (3500 Parsifal, N.E., Albuquerque, N. Mex.) Filed June 22, 1959, Ser. No. 821,954 3 Claims. (11. 145-50) This invention relates to screw drivers and more particularly it relates to an attachment for preferably a power type of screw driver wherein the screw can be held firmly by the screw driver bit prior to and during the time that the screw is being run into its position.

It is an object of this invention to provide a screw driver which positively holds the screw while the latter is being screwed into position and which has a movable jaw which increased its grip on the screw in response to screwing action.

Another object of this invention is to provide a screwholding screw driver bit which employs the movable jaw to apply torque on the screw, and which is particularly adaptable to powered screw drivers, and which can be made in the form of an attachment for powered screw drivers.

Still another object of this invention is to provide a screw-holding screw driver bit wherein the greater the torque applied to the screw, the greater the holding force becomes.

Still another and more particular object of this invention is to provide a cam lock or other positive lock type of screw-holding screw driver bit such that the screw being worked upon will be securely held, not only prior to engagement with the workpiece, but also during the time that the screw is being screwed into its fully seated position. Other objects and advantages will become apparent upon reading the following description in conjunction with the accompanying drawings wherein:

FIG. 1 is a top view of a preferred embodiment of a screw driver bit made according to this invention and showing part thereof in section, and also showing the end of a power screw driver in dotted lines.

FIG. 2 is a side View of the screw driver bit shown in FIG. 1, and also showing a fragment of a screw assembled therewith.

FIG. 3 is a front end view of the bit shown in FIGS. 1 and 2, but with the camming ring removed.

FIG. 4 is a front end view similar to that of FIG. 3, but with the one-half of the bit in a different position.

The same reference numerals refer to the same parts among the several views.

The drawings show what may be termed a screw driver attachment 10, assembled with an end of a handle or power screw driver 11 shown only partly and in dotted lines, and also assembled with a clutch, which is also shown in dotted lines. It will, of course, be understood that the screw driver 11, or handle 11, whichever it may be, and the clutch 12, are both conventional and are merely shown for explanatory purposes relating to the attachment or bit 10, which forms the instant invention. The attachment or hit 11) is composed of a shank 13 having a reduced portion 14 with a flat face 16 for driving attachment to the clutch 12, or the handle or powered screw driver 11, as preferred and in any conventional manner. The shank 13 is made essentially in two halves 17 and 18, which are pivoted together by means of a pin 19 passing through the forward ends of the halves 17 and 18 as shown. Thus the shank or bit half 17 is fixed while the shank or bit half 18 is movable about the pin 19, which is the fulcrum. In this arrangement, it will thus be seen that the shank 13 has a half cut-out 21, which extends from the shoulder or wall 22, to the forward or screw-holding end of the attachment 10, and it nited States Patent extends for the semi-circular cross section of the shank 13. In this arrangement, it will now be seen and mentioned that a heel or end 23 of the half 18 abuts the wall or shoulder 22 to prevent the end 13 from moving or pivoting excessively out of relation with the stationary half 17. A ring or actuator 24 is slidably disposed over the shank 13 in the position shown so that the ring can slide, for instance, between the pin 19 and a cam follower portion 26 on the rear end of the bit half 18. It will be further seen that the rear end of the ring 24 has a cam or actuating surface 27, which is, of course faced toward the cam follower 26, and it will thus be understood that upon Sliding the ring 24 rearwardly on the shank 13, the cam 27 will engage the cam follower 26 to displace the latter radially inwardly with respect to the edge of the shank 13, and thus pivot the half 18 about the pin 19.

FIGS. 2 and 3 show the position of the bit jaws 28 and 29, which are on the bit halves 17 and 18 respectively. In this position, the jaws 28 and '29 are aligned with each other, as seen in FIG. 3, for instance, and in this position the screw 31 can be positioned, as shown in FIG. 2 with the jaws 28 and 29 disposed within the screw slot 32 in the usual manner of assembly between screw and screw driver bit. Then, when the actuator 24 is slid rearwardly on the shank 13, the cam 27 engages the cam follower 26 to cause the bit jaw 29 to move downwardly, as shown in FIG. 4, and the jaw 29 is thus offset with respect to the fixed position of the jaw 28. In this manner, the jaws 28 and 29 bind upon the screw 31 in the slot 32, and thus securely hold the screw 31 to the screw driver. In this arrangement of offsetting the jaw 29 to a lower position, as viewed in FIG. 4, the jaws 28 and 29 clamp onto the screw 31 more securely in a right hand screwing action, so that the screw driver holds the screw more firmly in accordance with the amount of screwing torque being applied at the point of the jaws 28 and 29. Also, the movable jaw or half 18 serves as a torque-transmitting member since it is connected at pin 19 and since the sleeve 24 abuts the rear portion of the half 18 when the latter is offset by the screwing action as indicated in FIG. 4. Of course, the cam lock is so designed that the screw driver can be easily removed from the screw 31 after the latter is set into position as desired, and this, of course, is accomplished merely by sliding the ring or actuator 24 forwardly to release the pivotal half 17 from its locked position on the screw 31. It should also be mentioned that this particular invention finds particular application in screwing wood screws into position, since the wood screw can be easily placed onto the jaws 28 and 29 and lock thereon, and then, where a powered screw driver is used, the screw driver can be operated and the screw brought up to position and run down to its final seated position, at which time the clutch will automatically operate to relieve further screwing action on the screw 31, so that the attachment 10 will not be rotated beyond a predetermined torque, which is the time when the screw 31 is fully seated, as desired.

While a specific embodiment of this invention has been shown and described, it will be obvious that certain changes can be made in the embodiment, and the invention, therefore, be limited only by the scope of the appended claims.

What is claimed is:

l. A screw driver for positively holding a screw in the slot of the latter, comprising a shank, a screw-slot engaging bit on one end of said shank and being partitioned along the length of said shank into two half-portions consisting of a fixed bit half-portion on one side of said bit and a movable bit half-portion on the other side of said bit, a pin extending through said portions in a direction transverse to the center-line plane of partition and being disposed adjacent said one end and with said movable bit portion being movable transverse to the slot of the screw for clamping the screw at said slot with the free ends of both said bit portions, and a sleeve on said shank and fully disposed over the other end of said movable bit portion, said sleeve and said other end of said movable bit portion including camming surfaces in slid ing contact for pivoting and securing said movable bit portion in a pivoted position of clamping on said screw, said camming surface on said movable bit portion being disposed to the side thereof located in the direction which said free end thereof moves for clamping and with said direction being counter-clockwise when viewed from said free end.

2. A screw driver for positively holding a screw in the slot of the latter, comprising a cylindrical shank, one end of said shank being longitudinally separated into two halves and including a fixed bit portion on one side thereof and a movable bit portion on the other side thereof diametrically opposite said one side and being pivotally attached to said fixed bit portion intermediate the ends of said movable bit portion for movement transverse to the slot of the screw for clamping the screw at said slot with the free ends of both said bit portions, the other end of said movable bit portion being of a radius slightly less than that of said fixed bit portion and including a portion projecting radially beyond the circumference of said other end and presenting a cam follower, and a cam ring of an internal circumference snugly slidable on said shank intermediate said free ends and said cam follower for engaging said cam follower to thereby pivot said movable bit portion into clamping relation with said screw.

3. A screw driver for positively holding a screw in the slot of the latter, comprising a cylindrical shank, one end of said shank being longitudinally separated into two portions with a planular face disposed longitudinally of said shank and said shank including a screw-slot engaging fixed bit portion on the free end of said shank, said shank also including a movable bit portion pivotally attached to said fixed bit portion immediately adjacent said free end and the free end of said movable bit portion for movement in a direction parallel to said face and out of alignment with said fixed bit portion and transverse to the slot of the screw for clamping the screw at said slot with said free ends of both said bit portions, the other end of said movable bit portion being of a radius slightly less than that of said fixed bit portion and including an end projecting beyond the circumference of said shank to present a cam follower, and a sleeve slidably mounted on said shank and being disposed only intermediate the pivot point and said cam follower and including a camrning surface faced toward said cam follower for engaging said cam follower to thereby pivot said movable bit portion out of alignment with said fixed bit portion for a clamping relation with said screw, the internal circumference of said sleeve being snug with the corresponding surface of said fixed bit portion and being of a radius slightly more than that of said other end of said movable bit portion for limiting movement of the latter during screwing action.

References Cited in the file of this patent UNITED STATES PATENTS 1,627,301 Wood May 3, 1927 1,699,306 Miller Jan. 15, 1929 1,915,546 Muller June 27, 1933 2,304,703 OLeary Dec. 8, 1942 2,737,988 Gearhart et al Mar. 13, 1956

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