US1923074A - Self opening die head - Google Patents

Self opening die head Download PDF

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US1923074A
US1923074A US572239A US57223931A US1923074A US 1923074 A US1923074 A US 1923074A US 572239 A US572239 A US 572239A US 57223931 A US57223931 A US 57223931A US 1923074 A US1923074 A US 1923074A
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head
chaser
die
mounting
latching
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US572239A
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Albert F Breitenstein
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GEOMETRIC TOOL Co
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GEOMETRIC TOOL Co
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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B23MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
    • B23GTHREAD CUTTING; WORKING OF SCREWS, BOLT HEADS, OR NUTS, IN CONJUNCTION THEREWITH
    • B23G5/00Thread-cutting tools; Die-heads
    • B23G5/08Thread-cutting tools; Die-heads with means for adjustment
    • B23G5/10Die-heads
    • B23G5/12Die-heads self-releasing
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10TTECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T408/00Cutting by use of rotating axially moving tool
    • Y10T408/73Tool or tool-support with torque-applying spline
    • Y10T408/75Relative motion of splined shaft and tool-support causing release of Tool from operating position

Definitions

  • This invention relates toan improvement in self-opening die-heads of the type having an oscillating chaser-operating member carried by a floating chaser-carrying member which is,.in
  • the main object of my pres'ent'invention is to organize andarrange the parts of a self-open ing die-head of the type referred to insuch man ner that the floating chaser-carrying member is not cramped nor thrown into an eccentric position withrespect to the mounting-member of the die-head.”
  • Fig. l is a view inside elevation of oneform which a self-opening die-head embodying my invention may assume; Y
  • Fig. 2 is a front end view thereof
  • Fig. 4 is a longitudinal sectional view taken on the line 4 '4 of Fig. 2, but one larger scale and assume when. the chasers of the die-head are in their'cutting positions; l v
  • Fig. 5 is' a view corresponding to Fig. 4, but showing the parts in the positions which they assume at the instant of the unlocking'of-the diehead and prior to the opening thereof;
  • Fig. 6 is a transverse sectional view taken on the line6-6of-Fig.4;
  • Fig. :7 is a broken transverse. sectional view itaken on the line 7+7 of.-F ig. 4;
  • Fig. 3 is a rear. end view t hereof, with a po'rshowing the'parts in the positions which they Fig. 8 is a broken view in longitudinal section taken on the line 8-8 of Fig. 6; Fig. 9 is a broken view in longitudinal section taken on the line 99 of Fig- 6;
  • Fig. 10 isa brokenlongitudinal sectional view taken on the line l0l0 of Fig. 6;
  • Fig. .11 a broken 'view in longitudinal taken on the line 1l--11 of Fig.6;
  • Fig. 12 is a perspective view of the lockingsegment, detached; and V V 5 ,Fig. 13 is a similar view of one of the chasers.
  • the particular die- -head herein chosen for the illustration of my invention includes a mountingmember, generally designated by the numeral 20 and consisting of a rearwardly-extending hollow shank 21 adapted to be mounted in the tur ret or other appropriate feature of a machine and an annular flange or head-portion 22 located at theforward end of thesaidshank and provided with a relatively-thin forwardly-extending dirt-excluding lip 23.
  • Thesaid mounting-member is provided with anaxial bore, generally designated by the numeral 24 and comprising a relatively-large forward portion 25, mainly located within the head-portion 22, and.
  • Each chaser is formed in its rear face with a slightly-inclinedtransverse groove 35 adapted to receive a similarly-inclined camlug 36 forwardly projecting froman oscillating chaser-operating ring 37 bearing'upon a cylindrical surface 38 upon the chaser-carrying member '28, just to the rear of the head-portion 29 thereof andforming the bottom of what constitutes the groove just referred to is formed by the back face of the head-portion 29 and the rear wall of which is formed by a retaining-plate 39 constituting, when assembled, a unitary feature of end of the bore 52fjust referred to, is enlarged the chaser-carrying member, but made separate for the purpos'eof ease of manufacture and 'assembly.
  • the said retaining-plate 39 is secured to the chaser-carrying member 28 by means of dowel-pins 40 and one or moreretaining-screws 41 (Fig.9).
  • the rear face of the chaser-operating ring 37 is formed with an annular rearwardly-opening groove 42, which houses.
  • a' locking-segment 43 which latter is provided with a pin '44 forwardly projecting into a clearance passage 45 in the said ring 37 and engaged on opposite sides by opposed tangential clamping-screws 46-46 mounted .
  • the ring 37 with their slotted ends exposed upon the periphery thereof and serving to adjust the position of the locking-segment 43 with respect to the chaser-operating ring 37 for the purpose of determining the size of the thread cut by the chasers 33 as will hereinafter appear.
  • the rear face of the locking-segment 43, adjacent one of its ends, is cut away to form a locking-abutment or shoulder 47 adapted to be engaged by the'head '48 of a reciprocating latchinghead 48 thereof and at its rear end against the bottom of the bushing 50.
  • the rear end of the said bushing as shown in Figs.
  • the saidchaser-operating ring 37 has projecting from its peripherya stud orpost 59 by 1y shown in Fig.
  • one or 'more'of the springs 51 may means of which the said ring may be turned counterclockwise to reset the die-head after it has been tripped by the retraction of the latchingplunger 49, as will hereinafter appear.
  • the chaser-carrying member 28 is organized with the mounting-member 2050 as to have limited axial movement with respectthereto and is normally slightly forward of its rearmost position by one or more plungers 60, rearwardly projecting through the retaining-plate 39 and engaging with the forward face of the head-portion 22 of the mount ing-member 20 (Fig. 9).
  • the chaser-carrying member 28, together with the parts carried thereby, is normally restrained from moving I forwardly from the DGSiL-IOI]. in whichit is shown in 4 to that shown in 5, by one or more helical springs 61 each of which encircles a screw 62 and is located in a chamber 63 formed partly in the chaser-carrying member 28 and partly in the retaining-plate 39, as clear- .is just be employed and the complementary screw 62 of each projects rearwardly and is threaded into;
  • the die-head herein chosen for the illustration of my invention is in condition a screwthrcading operation when its parts are in the positions in which they are shown in allof the figures of the drawings save ig. 5.
  • the chaser-operating ring 3 ? been turned counterclockwise so as to cause its camlugs 36 to simultaneously project all four of the chasers 33 inward into the bore 31 in position to cut a thread ona-piece of work such'as that represented by broken lines 64 in Figs. 4 and 5.
  • the die-head is moved axially toward the work or the work toward the die-head, as may be desired, until desired length of thread has been cut. Now if the axial bodily movement of the. diehead with respect to the work is stopped, but relative rotation between the die-head and the work is continued, the chaser-carrying mem- 3 her, together with the parts organized therewith, will be drawn slowly forward with respect to the mounting-member 20 as the threading operation continues until the latching-abutment 4?
  • the retaining'plate 39 constitutes a unitary feature of the chaser-carrying member 28 and is formed separately therespecific embodiment herein chosenfor illustration, but only as indicated in the appended claims.
  • a mounting-member having av tubular shank provided at its forward end with a flange-like head having a bushing-receiving passage therethrough; of a chaser-carrying unit slidable with respect to the said mounting-member and provided intermediate its front and rear ends with an annular groove, the rear wall of which is formed by a removable plate the rear face ofwhich is normally; spaced apart from the front face of the said flange-like head, chasers carried by the said chaser-carrying unit, an oscillating chaser-operating ring installed in the said annular groove and provided at its forward end with means for operating the said chasers and provided at its rear end with a latching abut- 1 V ment; spring means arranged to turn the said The die-head may be reset for anotherthread chaser-operating ring in one direction; a bushing having a bottom wall and installed in the said removable plate and projecting rearwardly into the said bushing-
  • a self-opening die-head the combination with a mounting-member having a tubular shank provided at its forward end with a flange-like head or annular flange; of a chaser-carrying unit slidable with respect to the said mounting-member and provided intermediate its front and rear ends with an annular groove, the rear wall of which is formed by a removable plate the rear face of which is normally spaced apart from the front face of the said flange-like head, chasers' carried by the said chaser-carrying unit, an oscillating chaser-operating ring installed in the said annular groove and provided at its forward end with means for operating the said chasers and provided at its rear endv with a latching abut ment; spring means arranged to turn the said chaser-operating ring in one direction; a bushing having a bottom wall and installed in thesaid removable plate and projecting rearwardly into the said bushing-receivingpassage in the said flange-like head of the mounting

Description

1933- A. F. BREITENSTEIN SELF OPENING DIE HEAD Filed Oct. 51, 1931 2 Sheets-Sheet 1 1933- A. F. BREITENSTEIN 1,923,074
SELF OPENING DIE HEAD Filed Oct. 31, 1951 2 Sheets-Sheet 2 sz 37115 2 42 gq 23 22 30 27 J ff #j ffl 56 55 55 2320 39 I 3625 /AW////////'%. Z43
m L- z 33 35 37 1/5 56 2a 22 Patented Au 22,1933- SELF, OPENING DIE HEAD Albert F. Breitenstein, New Haven, Conn., as-
' signorflto The Geometric Tool Company, New Haven, Conn., a Corporation Application October 31, 1931. Serial misvzass' 2 Claims. (c1. 10-06) V This invention relates toan improvement in self-opening die-heads of the type having an oscillating chaser-operating member carried by a floating chaser-carrying member which is,.in
5 turn, organized with a mounting-memberin such manner as to axially reciprocate with respect thereto for effecting the unlocking of the diehead by means of the draft exerted upon the chasers themselves by the work.
Self-opening die-heads of the type referred to, as heretoforeconstructed, have been open to the serious objection that the tension of the opening spring of the die-head has tended to cramp the floating chaser-carrying member when the diehead'is in its locked position, thus not only caucing stiffness of operation, but also causing the chaser-carrying member to assume a highly-objectionable eccentric position with respect to the mounting-member, which becomes more and more marked as wear takes place an incident to continued use.
The main object of my pres'ent'invention is to organize andarrange the parts of a self-open ing die-head of the type referred to insuch man ner that the floating chaser-carrying member is not cramped nor thrown into an eccentric position withrespect to the mounting-member of the die-head." With the above and other objects in view as will appear from the following, my invention. consists in a self-opening die-head having certain features, and combined and arranged in a novel manner, as will be hereinafter described andparticularly recited in the claims. 1
In the accompanying drawings;
Fig. l is a view inside elevation of oneform which a self-opening die-head embodying my invention may assume; Y
Fig. 2 is a front end view thereof;
tion'of the cover-plate broken away;
Fig. 4 is a longitudinal sectional view taken on the line 4 '4 of Fig. 2, but one larger scale and assume when. the chasers of the die-head are in their'cutting positions; l v
Fig. 5 is' a view corresponding to Fig. 4, but showing the parts in the positions which they assume at the instant of the unlocking'of-the diehead and prior to the opening thereof;
Fig. 6 is a transverse sectional view taken on the line6-6of-Fig.4; Fig. :7 isa broken transverse. sectional view itaken on the line 7+7 of.-F ig. 4;,
Fig. 3 is a rear. end view t hereof, with a po'rshowing the'parts in the positions which they Fig. 8 is a broken view in longitudinal section taken on the line 8-8 of Fig. 6; Fig. 9 is a broken view in longitudinal section taken on the line 99 of Fig- 6;
Fig. 10 isa brokenlongitudinal sectional view taken on the line l0l0 of Fig. 6;
Fig. .11 a broken 'view in longitudinal taken on the line 1l--11 of Fig.6;
Fig. 12 is a perspective view of the lockingsegment, detached; and V V 5 ,Fig. 13 is a similar view of one of the chasers. The particular die- -head herein chosen for the illustration of my invention includes a mountingmember, generally designated by the numeral 20 and consisting of a rearwardly-extending hollow shank 21 adapted to be mounted in the tur ret or other appropriate feature of a machine and an annular flange or head-portion 22 located at theforward end of thesaidshank and provided with a relatively-thin forwardly-extending dirt-excluding lip 23. Thesaid mounting-member is provided with anaxial bore, generally designated by the numeral 24 and comprising a relatively-large forward portion 25, mainly located within the head-portion 22, and.
section a relatively-smaller rear portion '26 mainly located within the shank 21. r n I Mounted within the bore 24 of the mountingmember 20, with capacity for reciprocating movement therein, is the hollow shank 27 of a chasercarrying member 28 having at its forward end a head-portion 29 corresponding substantially in diameter to the diameter of thevhead-portion 22 'of the said mounting-member 20.
longitudinally of the die-head structure-by a :key 34.
Each chaser, as shown, is formed in its rear face with a slightly-inclinedtransverse groove 35 adapted to receive a similarly-inclined camlug 36 forwardly projecting froman oscillating chaser-operating ring 37 bearing'upon a cylindrical surface 38 upon the chaser-carrying member '28, just to the rear of the head-portion 29 thereof andforming the bottom of what constitutes the groove just referred to is formed by the back face of the head-portion 29 and the rear wall of which is formed by a retaining-plate 39 constituting, when assembled, a unitary feature of end of the bore 52fjust referred to, is enlarged the chaser-carrying member, but made separate for the purpos'eof ease of manufacture and 'assembly. The said retaining-plate 39is secured to the chaser-carrying member 28 by means of dowel-pins 40 and one or moreretaining-screws 41 (Fig.9).
The rear face of the chaser-operating ring 37 is formed with an annular rearwardly-opening groove 42, which houses. a' locking-segment 43 which latter is provided with a pin '44 forwardly projecting into a clearance passage 45 in the said ring 37 and engaged on opposite sides by opposed tangential clamping-screws 46-46 mounted .in the ring 37 with their slotted ends exposed upon the periphery thereof and serving to adjust the position of the locking-segment 43 with respect to the chaser-operating ring 37 for the purpose of determining the size of the thread cut by the chasers 33 as will hereinafter appear. 1
The rear face of the locking-segment 43, adjacent one of its ends, is cut away to form a locking-abutment or shoulder 47 adapted to be engaged by the'head '48 of a reciprocating latchinghead 48 thereof and at its rear end against the bottom of the bushing 50. The rear end of the said bushing, as shown in Figs. 4 and 5, is adapted to reciprocate in a bore 52 in the head-portion 220': the mounting-member 20, The rear to accommodate a nut 53 or collar screw-threaded upon the projecting rear end of the latchingplunger 49 and serving to limit the forward movement thereof under the urge of the spring 51 and to also serve to retract the head 48 from engagement with the locking-segment 43 for unlatching the die-head in the manner to be hereinafter described. 'Secured by means of screws 54 to the rear face of the head-portion 22 of the mounting-member 20, is a washer-like coverplate 55 having a clearance recess 55., into which the rearend of the plunger 49 and the nut or collar 53 maymove on occasion, as will hereinafter appear. "The oscillating chaser-operating ring 37, be-
fore referred to, is urged to turn in a clockwise direction, as viewed from the front of the diehead, by a helical spring 56 housed within the annular groove 42 in the rear face of the said ring and bearing at one end against a pin57 rearwardly projecting into the said groove from the'ring 3"! itself, and at its opposite end bearing latching-abutment 4'7 of the latching-segment 43 againstthe head 48 of the latching-plunger 49. The saidchaser-operating ring 37 has projecting from its peripherya stud orpost 59 by 1y shown in Fig. 11 of the drawings.- pointed out, one or 'more'of the springs 51 may means of which the said ring may be turned counterclockwise to reset the die-head after it has been tripped by the retraction of the latchingplunger 49, as will hereinafter appear.
As before pointed out, the chaser-carrying member 28 is organized with the mounting-member 2050 as to have limited axial movement with respectthereto and is normally slightly forward of its rearmost position by one or more plungers 60, rearwardly projecting through the retaining-plate 39 and engaging with the forward face of the head-portion 22 of the mount ing-member 20 (Fig. 9).
The chaser-carrying member 28, together with the parts carried thereby, is normally restrained from moving I forwardly from the DGSiL-IOI]. in whichit is shown in 4 to that shown in 5, by one or more helical springs 61 each of which encircles a screw 62 and is located in a chamber 63 formed partly in the chaser-carrying member 28 and partly in the retaining-plate 39, as clear- .is just be employed and the complementary screw 62 of each projects rearwardly and is threaded into;
the head-portion 22 of the mounting-znen'iber 20.
The die-head herein chosen for the illustration of my invention is in condition a screwthrcading operation when its parts are in the positions in which they are shown in allof the figures of the drawings save ig. 5. In this position, the chaser-operating ring 3? been turned counterclockwise so as to cause its camlugs 36 to simultaneously project all four of the chasers 33 inward into the bore 31 in position to cut a thread ona-piece of work such'as that represented by broken lines 64 in Figs. 4 and 5.
The die-head is moved axially toward the work or the work toward the die-head, as may be desired, until desired length of thread has been cut. Now if the axial bodily movement of the. diehead with respect to the work is stopped, but relative rotation between the die-head and the work is continued, the chaser-carrying mem- 3 her, together with the parts organized therewith, will be drawn slowly forward with respect to the mounting-member 20 as the threading operation continues until the latching-abutment 4? of the latching-segment43 has been moved foiwvardiyw clear of the head 48 of the latching-plunger 49, which latter is held against forward movement at this time by the engagement of the forward face of the nut or collar 53 with an abutment such as the abutment 53 in the bore 52 and/or the rear end of the bushing 50, as indicated in Fig. 5, which figure shows the parts in the positions which-they assume at the instant of such disengagement.
approximately the The, spring 56 will now be enabled toassertunder the urge of the springs 61 to thus restore the parts to the positions in which they are shown in Fig. 4, save that the latching plu'nger 49 will be moved slightly rearwardly by' the engagement of the rear face of the latching-segment 43 with the forward end'o'f the said latching-plunger. This rearward displacement ofthelatching-plunger the plate 55, into which the collar 53 will be free to move.
ing operation by turning the chaser-operating ring 3'7 counterclockwise so as to relatch the abutment 47 of the latching-segment 43 with the head 48 of the latching-plunger 49.
Practically all of the major elements of my improved die-head are admittedly old individually, but what I wish to call attention to is the fact that the tension of the spring 56, owing to the novel arrangement of the parts, does not tend to'cramp the chaser-carrying member 28 with respect to the mounting-member 20, to thus either prevent necessary freedom of movement or'to throw the said chaser-carrying member into a position eccentric with respect tothe mountingmember. The objections just referred to are mainly obviated by the fact that the thrust of the spring 56, as the parts are herein organized,
can only tend to cramp the retaining-plate 39 with respect to thechaser-carryin'g member 28, which, of course, cannot take place owing to the fact that they are, to all intents and purposes, a unit. 7
As before pointed out, the retaining'plate 39 constitutes a unitary feature of the chaser-carrying member 28 and is formed separately therespecific embodiment herein chosenfor illustration, but only as indicated in the appended claims.
I claim:
1. In a self-opening die-head, the combinationwith a mounting-member having av tubular shank provided at its forward end with a flange-like head having a bushing-receiving passage therethrough; of a chaser-carrying unit slidable with respect to the said mounting-member and provided intermediate its front and rear ends with an annular groove, the rear wall of which is formed by a removable plate the rear face ofwhich is normally; spaced apart from the front face of the said flange-like head, chasers carried by the said chaser-carrying unit, an oscillating chaser-operating ring installed in the said annular groove and provided at its forward end with means for operating the said chasers and provided at its rear end with a latching abut- 1 V ment; spring means arranged to turn the said The die-head may be reset for anotherthread chaser-operating ring in one direction; a bushing having a bottom wall and installed in the said removable plate and projecting rearwardly into the said bushing-receiving passage in the said flange-like head of the mounting-member; a reciprocating latching-plunger having a head and located in-the said bushing and projecting rearwardly through the bottom wall of the same, a
collar mounted upon the said projecting end of the said plunger and engageable with an abutment carried by the said mounting-member to member and closing the bushing-receiving passage therein.
' 2. In a self-opening die-head, the combination with a mounting-member having a tubular shank provided at its forward end with a flange-like head or annular flange; of a chaser-carrying unit slidable with respect to the said mounting-member and provided intermediate its front and rear ends with an annular groove, the rear wall of which is formed by a removable plate the rear face of which is normally spaced apart from the front face of the said flange-like head, chasers' carried by the said chaser-carrying unit, an oscillating chaser-operating ring installed in the said annular groove and provided at its forward end with means for operating the said chasers and provided at its rear endv with a latching abut ment; spring means arranged to turn the said chaser-operating ring in one direction; a bushing having a bottom wall and installed in thesaid removable plate and projecting rearwardly into the said bushing-receivingpassage in the said flange-like head of the mounting-member; a reciprocating latching-plunger having a head and located in the said bushing and projecting rearwardly through the bottom Wall of the same, a collar mounted upon the said projecting end of the said plunger and 'engageable with an abutment carried by the said'mounting-member to limit the forward movement of the said plunger; and a spring encircling the shank of the plunger and interposed between the bottom of the chamber in the bushing and the head of the plunger,
and a cover-plate secured to the saidfiange-like head and recessed to provide clearance for the collar of the said'plunger. V
' ALBERT F. BREITENSTEIN.
US572239A 1931-10-31 1931-10-31 Self opening die head Expired - Lifetime US1923074A (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2681460A (en) * 1949-05-13 1954-06-22 Landis Machine Co Externally operated die head

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2681460A (en) * 1949-05-13 1954-06-22 Landis Machine Co Externally operated die head

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