US2538350A - Socket head screw - Google Patents

Description

Jan. 16, 1951 G. H. J. BAULE 2,538,350

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Patented Jan. 16, 1951 UNITED STATES PATENT OFFICE Gerhard H. J. Baule, Salina, N. Y. I

Application September 5, 1945, Serial N0. 614,458

3 Claims. (01. 85 -45) This invention relates to threaded members orscrews of various types, and has for its object a:

screw particularly for mass production or for assembly work by automatic machines, although the screw is also operable by hand screw drivers, which screw is provided with a driving-tool-receiving recess or socket for receiving the tool of such shape or formation that when the tool is received in the socket or recess, the screw because of the shape of the recess, is held from falling off while being transferred from the receiving or pick-up station, magazine or hopper to the place the screw i to be applied and the tool releases from the screw by a withdrawing movement of the tool. More specifically, it has for its object a screw, the head of which is formed with a noncircular or angular driving tool receiving socket, at least a portion of which is twisted slightly or of spiral formation of less than one convolution,

the spiral preferably leading in such direction that the tool leads into the socket during 'turning in a driving direction and pulls out as the tool frees itself of the screw by withdrawing the tool with no turning force applied. 7

The invention consists in the novel features and in the combinations and constructions hereinafter set forth and claimed.

In describing this invention, reference is had to the accompanying drawings in which like character designate corresponding parts in 2.1 the views.

Figure 1 is an enlarged isometric view of a screw embodying thisinvention.

Figure 2 is a plan view of parts seenin Figure 1.

Figure 3 is a fragmentary isometric sectional ew through the head of the screw and contiguous portions of the shank.

Figure 4 is a view similar to Figure 3 of a slightly modified form.

Figure-5 is a view similar to Figure 4 of a second modified form.

Figure 6 is a sectional view of the screw head and one form of driving tool for the screw.

l and 2 designate respectively the inner and outer recesses of a driving-tool-receiving socket, the socket being formed axially in the'head 3 of a screw 4, the inner recess I only being twisted or of helical formation of less than one convolution, the helical curve being clearly shown by the corners 5 formed by the side walls of the inner recess 1. The socket, as here shown, is hexagonal.

The outer recess Zis here shown as, and preferably is, of larger diameter than the inner rehere shown asa right angle.

cess l, but as indicated by its corner lines 6 of its polygonal sides is here shown as not of helical formation, but it may be helical of different angle.

In the. form shown in Figures 1, 2 and 3, the wall of the outer recess 2 is beveled or tapers from the outer face of the screw to the upper end of the inner recess 1. '-As shown in Figure 4, the outer recess 2:0 is formed with a circumferential wall 1 and a bottom wall 8 which meet at an angle,

The difference between the'operation of the recesses 2 and 20 will be hereinafter set forth. In Figure 5, the spiral formation of the inner recess is provided by spirally extending splines 8. The sockets may be formed byany suitable process and the socket here shown has a fiat bottom, although if formed with a boring tool would incidentally have a conical bottom.

The socket in the head of the screw is for receiving a screw-driving tool of any suitable construction, and the outer recess coacts with the driving tool to hold the screw from dropping off.

the tool afterit'has been picked up by the tool and is beingjransferred to the hole in which it is to be screwed. The 'tool itself may be of any construction, and in Figure 6, l0 "designates the shank of aitool, which is actuated inany suitable manner, the shank having a head, ll of spiral formation for turning into the socket or recess l thereof. Ajn axial movable locking member, .as the sleeve I2, is slidably mounted on the shank H) of the tool, this sleeve being shown as beveled at its lower end for entering the recess 2. This also is hexagonal, or the same shape. in cross section as the recess 2'. The carrier l4 is here shown as guided in'grooves in a collar l-s1ecured to the shank ll) of the tool. The locking sleeve I2 is shown as pressed into locking position by the spring l3 encircling the shank I0 and interposed between the collar l5 and the sleeve l2. As the tool enters the socket, the sleeve I2 is pushed back until the angles or corners of the sleeve aline with the corners of the outer recess. When the spiral end of the tool enters the inner recess to some extent, the end of the sleeve will contact the recess 2, but at this time, the non-circular shape of the sleeve end is not lined up with the noncircular shape of the recess. Continuing the insertion of the spiral end of the tool by combined reaches a position near the bottom of the helical recess, the end of the sleeve I2 will be alined with and fit into the recess 2 and will hold the screw from dropping by turning oil? the driving tool, the sleeve still being yieldingly pressed into position by the spring 13. The locking sleeve may be Withdrawn against the action of the spring 13 by withdrawing the carrier M for the sleeve. This carrier may be actuated in any suitable manner. In the form shown in Figure 3, the tapered bottom of the outer recess 2 serves as a cam to dislodge the sleeve l2 and overcome the locking action when sufiicient withdrawing force entrance of the former recess and formed with is applied to the driving tool l0. Such pulling,

will tend to turn the tool, and hence the sleeve, in, a retrograde direction. In the form shown 'in' Figure 4, the driving tool Hlis positively held from retrograde turning, when a withdrawing force is applied, because the locking sleeve 12 fits" the angular channel or rabbet or recess 20 formed by its circumferential and'bottom" walls I and 8. Hence in the form shown in liigure 4, it is necessary to mechanically and forcibly withdraw the locking member or sleeve 12 before the driving tool can be pulled from thescrew or before the spiral head of the driving tool-can be withdrawn from the spiralrecess l of thescrew.

The method of forming thescrew with the driving recess forms no part Of'thiS'iHVBIltiOH.

In operation, the screw locks itself on the tool, due to the spiral tool-receiving recess I and the locking recess 2,

I What I claim is: 1. A screw having an axial, driving-tool-fitting socket for a tool of complemental' contour, the socket including a non-circular inner recess of helical formation in which the helices at the corners formed by the helices extend in a general direction lengthwise of the axis of the socket and the screw substantially the'depth of the recess, 4

and in which each is less than one convolution, and an outer recess inthe form of a countersink corner lines in line with the corner lines of the helicesi 1 15 3. A screw having an axial, polygonal, drivingtool fitti'ng'socket for a tool of complemental contour',-the socket including an inner recess, the sides of which extend in a general direction parallel to the axis of the, screw, the corner lines of the polygonal formation being helical and less than'one convolution, and an outer tool lock receiving recess in the form of a countersink at the entrance of the former recess, the outer recess being formed with corner lines in line with the outer ends of the helices, the bottom of the countersunk recess being beveled.

" GERHARD H. J. BAULE.

REFERENCES orrnn v The following references are of record in the file of this patent: I

' UNITED STATES PATENTS

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