US2449103A - Tap driver - Google Patents

Description

Sept. 14, 194.8.

H. P. BOGGIS TAP DRIVER Filed March 28, 194g;A

, www

INVENTUR.

HENRY P. BOGGIS ATTORNEYS Patented Sept. 14, 1948 UNITED STATES PATENT OFFICE 2,449,103 TAP DRIVER YHenry P. Boggis, Shaker Heights, Ohio Application March 28, 1944, Serial No. 528,497

4 Claims. (Cl. 279-55) This invention relates as indicated to tap drivers and in general to tool holders adapted to directly embrace, in driving communication, tools such as taps which are provided with a cylindrical shank and generally a polygonal terminal portion through which the driving forces are transmitted. The cylindrical portion of the tool is required to be maintained in axial alignmentv with the axis of rotation of the driving means such as a spindle of a drill press or like equipment. The cylindrical surface of the tool by which such axial alignment may be maintained does not provide for the transmission of the driving force from the holder to the tool, and accordingly the tool is generally provided at its nonoperating end with a polygonal surface which may be square, rectangular, or in the form of a flat tongue.

In the manufacture of tools of this character,

it is quite difficult to maintain in alignment the axis of the cylindrical portion of the tool and the axis of the polygonal portion through which driving communication is established. If the holder for the tool is provided with truly axially aligned portions adapted to embrace the cylindrical and polygonal portions of the tool respectively, the clamping forces to which the tool is subjected in being xed in the holder will result in the setting up in the tool of forces which may result in the end thereof being forced out of line, or the setting up of internal stresses in the tool itself which are highly undesirable.

It is a principal object of my invention, therefore, to provide a structure which will not only engage the tool in its cylindrical portion and maintain the tool coaxially with the axis ofrotation of the holder, but at the same time, embraces the polygonal portion of the tool and transmits the driving force thereto without placing the tool under any of the objectionable stresses above mentioned.

Other objects of my invention will appear as the description proceeds.

To the accomplishment of the foregoing and related ends, said invention then comprises the features hereinafter fully described and particularly pointed out in the claims, the following descripton and the annexed drawing setting forth in detail certain illustrative embodiments of the invention, these being indicative, however, of but a few of the various ways in which the principle of the invention may be employed.

In said annexed drawing Fig. 1 is a side elevational view partially in section along a vertical plane passing through the longitudinal axis of the tool and showing one embodiment of my invention;

Figs. 2, 3 and 4 are transverse sectional views of the structure illustrated in Fig. 1, taken on planes respectively indicated by the lines 2 2, 3 3, and 4 4; 1

Fig. 5 is a perspective View of the floating driven block which is one of the parts of the assembly illustrated in Fig. 1; and

Fig. 6 is a perspective view of the floating driver block likewise comprising one of the parts of the assembly illustrated in Fig. 1.

Referring now more specifically to the drawing and more especially to Fig. 1, the structure here illustrated comprises a body I which is generally cylindricalin form, and to the rear end of which there is integrally connected a taper or straight shank 2 terminating in a flattened end 3. The shank 2 is coaxial with the axis of the cylindrical portion I of the body and ground to a suitable taper such as a Morse taper so that the tool may be held in a conventional drilling or tapping machine.

The forward end 4 of the body I is coniform on its interior and thus adapted to receive a coniform collet 5. The external surface 6 at the end of the body I is a ground cylindrical surface adapted to be closely embraced by the ground surface 'l on the inside of the nut 8. The open end of the nut 8 is threaded and in threaded engagement with threads formed at 9 in an intermediate area on the body I. Openings I0 are provided at clrcumferentially spaced points on the nut 8 and adapted to receive a tool such as a Spanner wrench to assist in applying and removing the nut 8 on the body I.

The nut 8 at its forward end is provided with an inwardly extending flange II having a coniform shoulder I2 adapted to engage a complementary coniform shoulder on the collet 5.

The collet 5 is centrally provided with a cylindrical opening adapted to closely embrace and telescopically engage the cylindrical-portion I3 of a tool such as I4 which is illustrated as a tap. The

' non-operating end I5 of the tool is polygonal in cross-section, the illustrated embodiment being square as most clearly shown in Fig. 3.

The end I5 of the tool is closely embraced in a corresponding opening formed` centrally in the floating driven block I6 whose outer periphery is cylindrical and of a diameter slightly less than the inside diameter of the body I. In axial alignment with the floating driven block I6 is a cylindrical floating driver block4 I'I, the latter being mounted for relative rotatable and axial movement on a pin I8 carried by the body and arranged so that the axis intersects the axis of the body I at right angles.

As most clearly illustrated in Figs. 5 and 6, the contiguous faces of the members I6 and I7 are provided with a, complementary tongue and groove connection which, in the illustrated embodiment, includes a tongue I9 formed on the member I6, and a groove 2i] on the member II. The member I6 has a central aperture 2 I' extend ing therethrough from the bottom of the opening which is adapted to receive the end I5 of the tool.

It should be pointed out that the opening the member I6 for the reception of the end I5 of the tool may be a stepped opening so Vas to accommodate tool-s having ends of different sizes or it may be desirable to provide a series of inter# changeable members I6 each provided with a different opening for the reception of such different sizes and shapes of tool ends as the holder may be required to accommodate.

From the foregoing description, it will be obl served that when a tool such as a tap" I 4 is assembled in' the holder, the ground complementary cylindrical surfaces on the inside of the nut and the forward end of the body, and the ground complementary coniiorm surfacesl on the periphery of the collet and the inside end of the body, and the ground complementary cylindrical surfaces on the outside of thev tool and the inside of the ollet, make it possible to -very accurately maintain the axis of the tool in alignment with the axis Qi the holder. Y

As previously indicated, the driving end l5 of the tool may, however, have its axis out oi align ment with the axis of the cylindrical surface I3. Any such nii-salignment will be automatically compensated for by the floating driving connection which comprises the members l5, i7, and the pin I8. y

By this construction,- drivirig communication is established between the holder and the end of the tool without subjecting the tool to bending stresses and the like which might otherwise result m'isalignrhent between the axes of the cylinf drioal portion i3 and the terminal portion I5 of the tool. Y

i @ther modes of applying the priniple of the invention may be employed; change being made as "aras me details described, provided the fe ures stated in any of the following claims or the eduivalent of such be employed.

Iuthereiore, particularly point out and dis# tinctly claim as my invention:

1. A tool holder comprising a body having a driving shank; means for maintaining 'a tool in substantially axial alignment with said shank; and a'oating driving connection between said body and the tool, comprising a transversely ar-` ranged pin said body, a driving block movably moiinte'd on said pin, and aoating driven block adapted to engage the end of the tool, and a complementary tongue and groove connection between said driving block and driven block.

Y 2; Atool holder comprising a body having a driving shank; means for maintaining a tool in substantially 'axial alignment with said shank; and ariioatingY driving connection between said and a polygonal terminal portion of the tool, comprising a pin in said body, the axis of which lies in a plane normal to the axis lof said body,

a driving block mounted for rotatable and axial movement on said pin, vsaid block provided with a face normal to the axis of said body, and a. floating driven block adapted to closely embrace the polygonal terminal of the tool and presenting a face closely adjacent and substantially parallel to the face on said driving block, and a complementary tongue and groove connection on said faces.

3`. A tool holder comprising a body' including a tapered driving shank; means for maintaining a t-ool in substantially axial alignment With said shank comprising a collet having coniform telescopic engagement with said body and substantially cylindrical telescopic engagement with the tool, and a nut threaded on said body and having close-fitting cylindrical telescopic engagement therewith and engageable with said collet to move said collet and Ibody relatively axially; and a floating driving connection between said body and a polygonal terminal portion of the tool', comprising a pin iii-said body, the axis of which lies in a plane normal to the axis of' said body, a driV-fing block mounted for rotatable and axial movement on said pin, said block provided with a face normal to the axis of said body, and a floating driven block adapted to closely embrace the polygonal terminal of the tool and presenting a face closely adjacent and substantially parallel tothe face on said driving block, and a comple; mentary tongue and groove connection on said faces.

4; A tool holder comprising a body having a driving shank, means for maintaining a tooll in substantially axial alignment with said shank,

axially adjacent driving and driven blocks loosely tting within said body, said block-s having a complementary tongue and groove lconnect-ion between them for permitting relative transverse movement thereof in said body, Said driven block being formed Witl a lsoc'lket for driving engag'- n'et with the etid of the tool, and 'means Slipporting said drivingv block for' rotation in unison with said body and for transverse I'n-ovement in said body alongr` a line angularly disposed with respect to the line of transverse movement permitted by the tongue and groove connect-ion of said blocks.

HENRY P. B'QCMErIS.n

REFERENCES CITED A`The, following references vare of record in the file of this patent:

UNITED STATES PATENTS Ilurfiber` Name Date 952,153 Warme Mar. 15, 1910 1,( )37,'79Afg Y P rocuni'er Sept. 3, 1912 1,220,149 wimams Mar. 20, 1917 1,376,791 Bakel* et al May 3, 1 921 1,463,497 Busatti July 3i, i923 1,506,331 Benko Aug. 2.6', 1924 1,607,804 snyder Nov. 23, 1926 1,630,541 sandstrom May 31, 1927 1,857,012 Corley May '3, 1932 1,863,103 'ien'zer June 14, 1932 2,206,047 loorman July 2, 1940 2,242,305 Koehler et ai May 20, 1941 2,256,611 Cote Sept. 22, 1941 2,278,768 Calvert -1 Apr. 7, 1942

Images