US1898132A - Thread cutting die and holding clip therefor - Google Patents

Description

Feb. 21, 1933. Q Q, E, KOEHLER ET AL 1,898,132

THREAD CUTTING DIE AND HOLDING CLIP THEREFOR Filed July 10, 1931 J6 5 flmn mp4;

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VM *M Patented Feb. 21, 1933 UNITED STATES PATENT, OFFICE OSCAR E. KOEHLER AND WILLIAM B. DU MONT, OF GREENFIELD, MASSACHUSETTS,

ASSIGNORS TO GREEN'FIELD TAP & DIE- OOZIPORATION, OF GREENFIELD, MASSA- CHUSETTS, A CORPORATION OF MASSACHUSETTS THREAD CUTTING DIE AND HOLDING- CLIP THEREFOR Application filed July 10,

This invention relates to thread cutting dies and holders and particularly to such devices in which a set of two separate die blocks is used for cutting each difierent size 5 or number of thread.

It is customary to furnish these die blocks in sets comprising several different pairs with a single die holder, so that the different pairs of blocks may be selectively inserted in the holder for cutting a considerable range of thread sizes. 7

The object of our inventionis to provide improved means for holding each pair of die blocks in assembled relation, whether in use or in storage. I

More specifically, we provide an improved sheet metal clip in which a pair of die blocks may be assembled and yieldingly secured but from which the blocks may be easily removed'when desired.

Preferred forms of our invention are shown in-the drawing, in which Fig. 1 is a plan view of a die holder provided with our improvements;

Fig. 2 is a sectional side elevation, taken along the line 22 in'Fig. 1;

Fig. 3 is a plan view of a blank from which our improved clip is formed;

Fig. 4 is a side elevation of the clip after the blank is bent to finished form;

Fig. 5 is an end elevation of the clip, looking in the direction of the arrow 5 in Fig.4;

Fig. 6 is a plan view of a slightly modified form of clip;

Fig. 7 is an end view of the clamping member, looking in the direction of the arrow 7 in Fig.2; 7 i

Fig. 8 is an end view of one of the die blocks;

Fig. 9 is a. plan view of a blank used in forming a clip of a further modified con-- struction; I

Fig. 10 is a detail sectional view, taken along the line 1010 in Fig. 9, and

Fig. 11 is a side elevation of the clip formed from the blank shown in' Fig. 9.

Referring to the drawing, we have shown a die holder or collet 10 adapted to be secured in a suitable handle or chuck. This die holder 10 is provided with a rectangular 1931. Serial No. 549,941.

opening 11 having outwardly converging side walls adapted to be engaged by the beveled sides 12 of a pair of die blocks 13.

The die blocks are inserted in the holder 10 from the back side and are secured therein by a clamping member 15, threaded'into a circular recess 16 in the back of the holder. The clamping member 15 also preferably acts as a guide for the stock to be threaded, and is provided with spaced guiding portions 17, separated by openings 18 through which chips may escape; Preferably, a separate guiding member 15 is provided for each diameter of stock to be threaded.

Adjusting screws 20 in the holder 10 engage the outer end faces of the die blocks 12 and are used to adjust the die blocks inward to correct position to cut a thread of a desired diameter. Each die block is provided with shallow grooves 22 (Fig. 8) in its upper and lower faces, extending longitudinally and for a purpose to be described. 2

Our improved holding clip C may be formed from a rectangular blank of thin and preferably resilient sheet metal 30, as indicated in Fig. 3. This blank is then provided with cut out portions 31 and-32 and with longitudinally extending displaced portions or ridges 33. After the blank is thus formed, it is bent to the open rectangular outline shown in Fig. 4:, with the openings 32 extending across the ends of the clip and with the ridges 33 directed inwardly or towards each other. 7

When a pair of die blocks 13 is assembled in a holding clip G, the ridges '33 are seated blocks and clip witho'ut disturbing the adjustment of the screws 20.

Our improved holding clip may be easily and economically manufactured and requires no change in the construction of the usual die blocks, except the provision of the grooves 22, which are easily formed and which do not in any substantial way weaken the construction of the die blocks.

The use of our improved holding clip not only retains the two die blocks of a pair in assembled relation so that they will not be mismated but also holds the die blocks in such relative position that the cutting teeth are not readily injured. 7

The assembled dies may also be more easily and quickly inserted in a collet orholder. While shown in connection with a removable collet, the invention is equally adapted for use in a construction in which the collet or holder forms an integral part of the die stock.

In Fig. 6 we have shown a slightly modified construction in which the middle portion of the blank is outwardly enlarged or displaced to form a wider opening 35. This form may be used with die blocks for cutting threads of larger relative diameter.

In Figs. 9, 10 and 11 we have shown a further form of our invention Which avoids the necessity of grooving the'die blocks. A blank from which this form of our invention may be constructed is shown in Fig. 9 and comprises a piece of thin resilient sheet metal rovided with an enlarged center opening 40 in the bottom thereof, with rectangular openings 41 in the end portions thereof, with slight projections 42 in the extreme ends ofthe blank, and with outwardly inclined flanges 43 rojecting upwardly from the opposite ends of the bottom portion M of the blank.

After being thus formed, the blank is bent to the open rectangular construction shown in Fig. 11 and is adapted to engage and detachably secure the die blocks in assembled relation as in the previo'us constructions.

The flanges 43 project upwardly a suiiicient distance to engage the lower edges of the beveled side portions of the die blocks and to thereby prevent lateral displacement thereof. The slight projections 42 are on the inside of the clip when the latter is bent to final position and project slightly into the clearance openings of the die/blocks, thus yieldingly preventing the die blocks from sliding toward each other in the clip.

Otherwise the clip is substantially similar to the forms previously described and possesses the same advantages, together with the additional advantage that this clip may be used with the regular commercial die blocks and without any change or addition thereto.

Having thus described our invention and the advantages thereof, we do not wish to be limited to the details herein disclosed, otherwise than as set forth in the claims, but what we claim is 1. A screw threading device comprising a die holder, a pair of separable die blocks mounted to slide in said holder, and an additional die-holding clip in which said die blocks may be detachably assembled before insertion in said die holder, said clip being formed of thin sheet metal and having portions engaging the tops, bottoms and outer ends of said die block, said clip also having provision for preventing lateral displacement of said blocks therefrom.

2; A screw threading die and holding clip therefor, comprising a pair of die blocks and aclip formed of thin sheet metal and having portions engaging the tops, bottoms and outer ends of said die blocks, said die blocks each having longitudinal depressions in their top and bottom surfaces and said clip having inwardly displaced portions seated in said longitudinal depressions and preventing lateral displacement of said die blocks relative to said holding clip.

3. A screw threading die and holding clip therefor, comprising a pair of die blocks and a clip formed of thin sheet metal and having portions engaging the tops, bottoms and outer ends of said die blocks, said clip also having provision for preventing lateral displacement of said blocks therefrom and having slots extending across the end portions to provide clearance for the block-engaging ends of adjusting screws.

Al. A screw-threading device comprising a die holder, a pair of separable die blocks mounted to slide in said holder, and an additional die-holding clip in which said die blocks may be detachably assembled before insertion in said die holder, said clip being formed of thin sheet metal and having portions engaging the tops, bottoms and outer ends of said die block, said blocks and clip havingengaging portions effective to prevent accidental lateral displacement of said blocks.

5. A screw-threading device comprising a die holder, a pair of separable die blocks mounted to slide in said holder, and an additional die-holding clip in which said die blocksmay be detachably assembled before insertion in said die holder, said clip being formed of thin sheet metal and having portions engaging the tops, bottoms and outer ends of said die block, said holding clip being open at the sides and leaving the sides of the die blocks free and unobstructed.

6. A holding clip for die blocks comprising a substantially rectangular frame of light resilient metal, said frame being open at the sides and having openings through the bottom and both ends and the top portion discontinuous and partially open, the bottom and top portions of said clip having inwardly depressed longitudinal ridges formed there- 7. A screw-threading device comprising a die holder, a pair of separable die blocks mounted to slide in said holder, and an additional die-holding clip in which said die blocks may be detachably assembled before insertion in said die holder, said clip being formed of thin sheet metal and having portions engaging the tops, bottoms and outer ends of said die block, said holding clip also having inwardly projecting flanges along the opposite side edges of the bottom effective to prevent lateral displacement of the die blocks therefrom.

8. A screw threading die and holding clip therefor, comprising a pair of die blocks and a clip formed of thin sheet metal and having portions engaging the tops, bottoms and outer ends of said die blocks, said clip having its bottom portion outwardly enlarged and recessed at its middle part and having inwardly projecting flanges at each end of said enlarged portion for preventing lateral dis-7 placement of the die blockstherefrom.

9. A screw-threading device comprising a die holder, a pair of separable die blocks mounted to slide in said holder, and an additional die-holding clip in which said die blocks may be detachably assembled before insertion in said die holder, said clip being formed of thin sheet metal and having portions engaging the tops, bottoms and outer ends of said die block, said holding clip also having provision for preventing lateral displacement of said die blocks therefrom and having additional means to prevent displacement of said die blocks by sliding movement toward each other.

10. A. screw threading die and holding clip therefor, comprising a pair of die blocks and a clip formed of thin sheet metal and having portions engaging the tops, bottoms and outer ends of said die blocks, said clip also having provision for preventing lateral displacement of said blocks therefrom, and having slight inwardly projecting portions at the inner ends of the top members, which yieldingly prevent inward sliding movement of said die blocks.

In testimony whereof we have hereunto aflixed our signatures.

OSCAR E. KOEHLER. WILLIAM B. DU MONT.

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