US267215A - Metal-screw machine - Google Patents

Metal-screw machine Download PDF

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US267215A
US267215A US267215DA US267215A US 267215 A US267215 A US 267215A US 267215D A US267215D A US 267215DA US 267215 A US267215 A US 267215A
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tool
chuck
cam
spindle
screw
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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
    • B23Q—DETAILS, COMPONENTS, OR ACCESSORIES FOR MACHINE TOOLS, e.g. ARRANGEMENTS FOR COPYING OR CONTROLLING; MACHINE TOOLS IN GENERAL CHARACTERISED BY THE CONSTRUCTION OF PARTICULAR DETAILS OR COMPONENTS; COMBINATIONS OR ASSOCIATIONS OF METAL-WORKING MACHINES, NOT DIRECTED TO A PARTICULAR RESULT
    • B23Q1/00—Members which are comprised in the general build-up of a form of machine, particularly relatively large fixed members
    • B23Q1/25—Movable or adjustable work or tool supports
    • B23Q1/44—Movable or adjustable work or tool supports using particular mechanisms
    • B23Q1/56—Movable or adjustable work or tool supports using particular mechanisms with sliding pairs only, the sliding pairs being the first two elements of the mechanism
    • B23Q1/60—Movable or adjustable work or tool supports using particular mechanisms with sliding pairs only, the sliding pairs being the first two elements of the mechanism two sliding pairs only, the sliding pairs being the first two elements of the mechanism
    • B23Q1/62—Movable or adjustable work or tool supports using particular mechanisms with sliding pairs only, the sliding pairs being the first two elements of the mechanism two sliding pairs only, the sliding pairs being the first two elements of the mechanism with perpendicular axes, e.g. cross-slides
    • B23Q1/621—Movable or adjustable work or tool supports using particular mechanisms with sliding pairs only, the sliding pairs being the first two elements of the mechanism two sliding pairs only, the sliding pairs being the first two elements of the mechanism with perpendicular axes, e.g. cross-slides a single sliding pair followed perpendicularly by a single sliding pair
    • Y—GENERAL 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
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T29/00—Metal working
    • Y10T29/51—Plural diverse manufacturing apparatus including means for metal shaping or assembling
    • Y10T29/5168—Multiple-tool holder
    • Y10T29/5173—Longitudinally and transversely movable
    • Y10T29/5174—Rotary tool spindle

Definitions

  • This invention relates to automatic machines for making screws from a rod or long screw-stock, and has particular reference to the mechanism for bringing the toolssuch as lthe milling and threading, with or without other toolssuccessively into action upon the rod or screw-stock.
  • These tools are carried by independent longitudinal slides, which move in ways in a cross-slide and are brought successively into line with the chuck by automatic mechanism which shifts said crossslide, and when brought in line are advanced independently, also by automatic mechanism.
  • Figure 1 being a central "ertical longitudinal section; Fig. 2, a plan Fig. 3, a partial cross-section on line w x, Fig. 1; Fig. 4, a partial view in horizontal section and in plan, Fig. 5, a vertical cross-section on line y y, Fig. 1 Fig. 6, a bottom view in perspective of the longitudinal and cross slides; and Fig. 7, a perspective view of an auxiliary slide, through which motion is imparted t0 the longitudinal slides.
  • A is the machine-frame; B, the cam-shaft; C, the hollow chuck-spindle, having a pulley, C', fixed thereto, and geared to cam-shaft B throughtbe train of spur-gears b b b2, b3 b4 b5 bG ZF bg; D, a tube slotted at the end and secured in the head of the chuck-spindle, the chuck being screwed thereto.
  • the chuck-jaws d are pressed inward to clamp the rod orv screw-stock by means of at intervals by means of a cam, d8, on the disk d, keyed to the cam-shaft B, the said cam d8 acting through a lever, d?, fulcrumed on an extension of the machine-frame, and engaging by a forked upper end a collar, dg, on the tube d3.
  • This clamp is carried by a slide, e2, working on the hollow rod E3, and moved forward by the spring E2 acting .against the pin e and back by the lever E acting against the set-screw c, tapped into the boss e8.
  • the lever E is operated by the cam 0115011 disk d1?, to withdraw the clamp E before the pressure of the chuck-jaws is released,
  • the clamp E which has an upper and a lower jaw, is closed by the depression of the upper jaw through the arm dI3 on the lever (Z7 and the link d.
  • a tube, F having friction-fingers at each end, and held loosely in the chuck-spindle by the collar f, prevents the rod or screw-stock from being drawn back with the feed-clamp, and otherwise assists in the feeding operation.
  • the milling-tool or tool for turning down the rod to the diameter required for the screwthread, is of any ordinary or suitable construction.
  • the threading-tool comprises a die carried by a spindle, L, a sleeve, I, surrounding the spindle, a clutch, m, between the sleeve and the spindle, a spring, l', tending to engage said clutch, a gear, M, for rotating the sleeve l and for revolving also the die and diespindle L through said sleeve and the clutch m, and a safety stop-clutch, Z2 Z3 Z4 Z5 ZG, for holding the die and die-spindle stationary when required.
  • Motion is communicated to the gear M from a gear, N2, on the shaft N, through an idler, u?, supported by links u2 n3, so that the said gears do notinterfere with the lateral movement of IOS AVthe threading-tool, imparted as hereinafter detimes, except while unthreading the die, when the latter and its spindle are held stationary by the engagement of the projection Z4 on the die-spindle with the projection Z3 on the clutchbar Z2, the clutch m being disengaged.
  • rlhe clutch-bar Z2 is non-rotative, but is capable of a slight endwise movement against the pressure of the spring Z5, held in place by the screw Z6, so that, should the projections Z3 Z4 not fairly engage, the spring will yield and prevent the stripping of the newly-formed thread from t-he rod or screw-stock.
  • the tool-holder H is supported in guides or ways in the machine, and is moved laterally back and forth by means of a cam, h4, bellcrank lever 71,5, and connecting-rod hl.
  • the cam 71,4 is formed on the periphery of a drum, G, which is keyed to the cam-shaft B, so as to revolve with it.
  • the bell-crank lever h5 is pivoted at h5 to the machine-frame, and the rod hl is jointed at one end to the bell-crank lever and at the other to the tool-holder H.
  • the tool-slides are longitudinally movable at right angles to the movenient of the tool-holder, and parallel or in line with the axis of the chuck-spindle.
  • the rear end of the tool-holder (right-hand end, Figs. l and2) overhangs the longitudinal slide Kand a portion ofthe machine-frame, and is cut away underneath (see Fig. 5) to allow the necessary freedom of motion to a projection, 7c, which operates the tool-slides. opening or groove, 7L', to receive the projection k.
  • the slide K moves back and forth in ways in the machine-frame, and is operated by the cam h2, on the drum G and the pin h3, scoured to the said slide.
  • a pin or stud, k2 extends into a hole in the tool-holder at each advance of the slide K and prevents lateral motion of the tool-holder, and secures the exact centering of the tool in line with-the axis of the chuck.
  • the cutting-oft'tool is shown at I), being adjustably connected with the tool-holder H.
  • the latter have each an In forming a screw the following operations take place:
  • the rod is fed forward a distance equal to the length of the screw; it is turned down to the required diameter by the millingtool; it is threaded by the die or threadingtool, and is severed from the rod by the cutoff tool.
  • the chuckjaws d and chuck-spindle, the sleeve Z, surrounding the die-spindle, and the camdrum G are revolved continuously, and during all, except that of feeding, the rod to be made into screws is also revolved.
  • the lever E In feeding, the clamp E being open, the lever E is operated by the cam 115, and, acting against the screw e, pushes back the clamp E a distance equal to the length ofa screw.
  • This distance is regulated by turning the screw e in the lug e8, so that it will be struck sooner or later by thelever E. While the clamp is held back by the cam d the wedges d2 are withdrawn, thus releasing the pressure of the chuck-jaws eZ on the rod, and
  • thejaws of the clamp E are closed by the action of the cam d8 ou the lever C17.
  • the cam ZB holds its lever in position until the lever E is released by its cam Zf and the feed-clamp has been advanced by the spring E2, when it also releases the lever dl.
  • the feed-clamp is thus ⁇ released, the chuck-j aws are immediately closed by the action ofspring du, and the rod rotates with the chuck.
  • the toolholder H has been moved by the cam h4, so that the milling-tool is in line with the axis of the chuck.
  • the slide K is now advanced by the cam h2, carrying with it the slide H ofthe milling-tool, and is then returned.
  • the cam h4 moves the tool-holder H laterally and brings the die or threading-tool in line with the axis of the chuck. By this lateral movement the projection 7c on the slide K is made to engage with the groove in the bottom of the tool-slide H2.
  • the cam h2 again advances and returns the slide K, which, at this reciprocation, carries with it the slide H2 of the threading-tool. During the advance ot' this tool the die-spindle is revolved, being engaged by thesleeve Z through the clutch m.
  • the return movement of the tool-slide causes the die-spindle L to be drawn forward in the sleeve Z, disengages clutch m, and effects the engagement of the projection Z4 with the projection Z3 on the clutch-bar Z2.
  • the die or threading-tool being held from turning by the projection on the clutch-bar, the continued revolution of the rod unthreads it.
  • Another lateral movement of the tool-holder H brings the cutting-tool into action and severs the screwjust made.
  • the tool-holder is now moved back by the cam h4, to bring the milling-tool again in line, and during the operation a new feed of the rod takes place.
  • tiled July 2l, 1881 an arrangement is shown whereby lateral movements are imparted to the chuck instead'of to the tools.
  • the independent tool-slides could be used with such a chuck, and the same arrangement of gearing as hereinbet'ore explained could be used t0 convey the motion from the chuck-spindle to the die-spindle.
  • die-spindle77 is employed herein as a convenient term-for the spindle of the threadingtool, which, it is obvious, may be a tap for cutting internal threads as well as a die for cut- In such a case, the milling-tool would be a drill to bore out the hole to be threaded, instead of a turning-down tool.
  • lateral movement,77 or f lateral movementback and forth,7 is used herein in contradistinction to the intermittent rotary movement of the ordinary turret employed in screwmachines, and is not limited to a rectilinear movement in guides, which is the preferred movement, and which is therefore provided for in the machine shown, but includes a vibratory or to-and-fro movement in short arcs of a circle.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Transmission Devices (AREA)

Description

(No Model.)
. I 3 Sheets---S-Ivleet'.'l 1;. ,A. JOHNSTON. METAL SCREW MACHINE.
N0. 267,215. Patented NOV. 7,1882..`
N NB Il v w V?\`\\ .f N g l', j I I F l :E
IM' 2-- I .M-.
m lIk T NFS X`%\ @l IV l gk l h b to P j d '1 f I a o y g, r l im e h il d I e s iv u 4 "is gbl-050', a E l y' Znz/@mor (No Model.) 3 sheets-sheen 2.
A. JOHNSTON.
METAL SGREW MACHINE.
No. 267,215. Patented Nov. "7, 1882.
(No Model.)
JOHNSTON 3 Sheets-Sheet 3.
' METAL SCREW MACHINE.
Patented Nov. 7 18 To all whom it may concern:
UNITED STATES PATENT GEEICE.
ALLEN JoHNsTof, 0F OTTUMWA, IOWA.
METAL-SCREW MACHINE.
SPECIFICATION forming part of Letters Patent No. 267,215, dated November 7, 1882.
Application filed July 5, 1882. (No model.)
Be it known that I, ALLEN JOHNSTON, of Ottumwa, county ol' Wapello, and State of Iowa, have invented a new and useful lmprovement in Metal-Screw Machines, which improvement is fully set forth in the following specification.
This invention relates to automatic machines for making screws from a rod or long screw-stock, and has particular reference to the mechanism for bringing the toolssuch as lthe milling and threading, with or without other toolssuccessively into action upon the rod or screw-stock. These tools, as herein shown, are carried by independent longitudinal slides, which move in ways in a cross-slide and are brought successively into line with the chuck by automatic mechanism which shifts said crossslide, and when brought in line are advanced independently, also by automatic mechanism.
In theaccompanyingdrawingsisrepresented a machine constructed in accordance with the invention, Figure 1 being a central "ertical longitudinal section; Fig. 2, a plan Fig. 3, a partial cross-section on line w x, Fig. 1; Fig. 4, a partial view in horizontal section and in plan, Fig. 5, a vertical cross-section on line y y, Fig. 1 Fig. 6, a bottom view in perspective of the longitudinal and cross slides; and Fig. 7, a perspective view of an auxiliary slide, through which motion is imparted t0 the longitudinal slides.
Before entering upon a description of those parts of the machine wherein the present invention resides it may be well brieiiy to explain the other elements, which may be of any ordinary or suitable construction, but which,
as shown, embody certain new improvements, subject-matter of my application tiled July 21, 1881, and numbered 38,250, whereof the present application is a division and continuation.
A is the machine-frame; B, the cam-shaft; C, the hollow chuck-spindle, having a pulley, C', fixed thereto, and geared to cam-shaft B throughtbe train of spur-gears b b b2, b3 b4 b5 bG ZF bg; D, a tube slotted at the end and secured in the head of the chuck-spindle, the chuck being screwed thereto.
The chuck-jaws d are pressed inward to clamp the rod orv screw-stock by means of at intervals by means of a cam, d8, on the disk d, keyed to the cam-shaft B, the said cam d8 acting through a lever, d?, fulcrumed on an extension of the machine-frame, and engaging by a forked upper end a collar, dg, on the tube d3. When the pressure of the chuck-jaws is relieved the rod or screw-stock is advanced by means of theclamp E. This clamp is carried by a slide, e2, working on the hollow rod E3, and moved forward by the spring E2 acting .against the pin e and back by the lever E acting against the set-screw c, tapped into the boss e8. The lever E is operated by the cam 0115011 disk d1?, to withdraw the clamp E before the pressure of the chuck-jaws is released,
and to allow the spring E2 to'advance the feedclamp while said pressure is relieved. During this advance movement the clamp E, which has an upper and a lower jaw, is closed by the depression of the upper jaw through the arm dI3 on the lever (Z7 and the link d. A tube, F, having friction-fingers at each end, and held loosely in the chuck-spindle by the collar f, prevents the rod or screw-stock from being drawn back with the feed-clamp, and otherwise assists in the feeding operation.
The milling-tool, or tool for turning down the rod to the diameter required for the screwthread, is of any ordinary or suitable construction.
The threading-tool, as shown, comprises a die carried by a spindle, L, a sleeve, I, surrounding the spindle, a clutch, m, between the sleeve and the spindle, a spring, l', tending to engage said clutch, a gear, M, for rotating the sleeve l and for revolving also the die and diespindle L through said sleeve and the clutch m, and a safety stop-clutch, Z2 Z3 Z4 Z5 ZG, for holding the die and die-spindle stationary when required. h
Motion is communicated to the gear M from a gear, N2, on the shaft N, through an idler, u?, supported by links u2 n3, so that the said gears do notinterfere with the lateral movement of IOS AVthe threading-tool, imparted as hereinafter detimes, except while unthreading the die, when the latter and its spindle are held stationary by the engagement of the projection Z4 on the die-spindle with the projection Z3 on the clutchbar Z2, the clutch m being disengaged. rlhe clutch-bar Z2 is non-rotative, but is capable of a slight endwise movement against the pressure of the spring Z5, held in place by the screw Z6, so that, should the projections Z3 Z4 not fairly engage, the spring will yield and prevent the stripping of the newly-formed thread from t-he rod or screw-stock.
For a more particular description of the various parts reference may be had to my beforementioned application, No. 38,250, wherein the same letters of reference are employed.
The parts to which the present invention relates are as follows:
The tool-holder H is supported in guides or ways in the machine, and is moved laterally back and forth by means of a cam, h4, bellcrank lever 71,5, and connecting-rod hl. The cam 71,4 is formed on the periphery of a drum, G, which is keyed to the cam-shaft B, so as to revolve with it. The bell-crank lever h5 is pivoted at h5 to the machine-frame, and the rod hl is jointed at one end to the bell-crank lever and at the other to the tool-holder H. Upon the tool-holder are carried aserics of tool-slides, H H2. rlwo are shown, one for the milling or turning-down tool and the other for the die or threading tool; but a larger number can be used, if necessary, for special purpose, or where deemed desirable. The tool-slides are longitudinally movable at right angles to the movenient of the tool-holder, and parallel or in line with the axis of the chuck-spindle. The rear end of the tool-holder (right-hand end, Figs. l and2) overhangs the longitudinal slide Kand a portion ofthe machine-frame, and is cut away underneath (see Fig. 5) to allow the necessary freedom of motion to a projection, 7c, which operates the tool-slides. opening or groove, 7L', to receive the projection k. The slide K moves back and forth in ways in the machine-frame, and is operated by the cam h2, on the drum G and the pin h3, scoured to the said slide. A pin or stud, k2, extends into a hole in the tool-holder at each advance of the slide K and prevents lateral motion of the tool-holder, and secures the exact centering of the tool in line with-the axis of the chuck.
The cutting-oft'tool is shown at I), being adjustably connected with the tool-holder H.
The latter have each an In forming a screw the following operations take place: The rod is fed forward a distance equal to the length of the screw; it is turned down to the required diameter by the millingtool; it is threaded by the die or threadingtool, and is severed from the rod by the cutoff tool. During all these operations the chuckjaws d and chuck-spindle, the sleeve Z, surrounding the die-spindle, and the camdrum G are revolved continuously, and during all, except that of feeding, the rod to be made into screws is also revolved. In feeding, the clamp E being open, the lever E is operated by the cam 115, and, acting against the screw e, pushes back the clamp E a distance equal to the length ofa screw. This distance is regulated by turning the screw e in the lug e8, so that it will be struck sooner or later by thelever E. While the clamp is held back by the cam d the wedges d2 are withdrawn, thus releasing the pressure of the chuck-jaws eZ on the rod, and
thejaws of the clamp E are closed by the action of the cam d8 ou the lever C17. The cam ZB holds its lever in position until the lever E is released by its cam Zf and the feed-clamp has been advanced by the spring E2, when it also releases the lever dl. The feed-clamp is thus` released, the chuck-j aws are immediately closed by the action ofspring du, and the rod rotates with the chuck. In the meantime the toolholder H has been moved by the cam h4, so that the milling-tool is in line with the axis of the chuck. The slide K is now advanced by the cam h2, carrying with it the slide H ofthe milling-tool, and is then returned. The cam h4 moves the tool-holder H laterally and brings the die or threading-tool in line with the axis of the chuck. By this lateral movement the projection 7c on the slide K is made to engage with the groove in the bottom of the tool-slide H2. The cam h2 again advances and returns the slide K, which, at this reciprocation, carries with it the slide H2 of the threading-tool. During the advance ot' this tool the die-spindle is revolved, being engaged by thesleeve Z through the clutch m. The return movement of the tool-slide, which is at first quick or sharp, causes the die-spindle L to be drawn forward in the sleeve Z, disengages clutch m, and effects the engagement of the projection Z4 with the projection Z3 on the clutch-bar Z2. The die or threading-tool being held from turning by the projection on the clutch-bar, the continued revolution of the rod unthreads it. Another lateral movement of the tool-holder H brings the cutting-tool into action and severs the screwjust made. The tool-holder is now moved back by the cam h4, to bring the milling-tool again in line, and during the operation a new feed of the rod takes place.
Various modications may be made in the details of construction of the improved screwmachines without departing from the spirit of the invention, and portions of the invention may be used without the others. For example, a friction or two-motion feed-clamp of ordinary IOO IOS
IIO
, ting external threads.
gearing, which give quick motions followed by periods of rest. y
In another application, tiled July 2l, 1881, an arrangement is shown whereby lateral movements are imparted to the chuck instead'of to the tools. The independent tool-slides could be used with such a chuck, and the same arrangement of gearing as hereinbet'ore explained could be used t0 convey the motion from the chuck-spindle to the die-spindle. The term die-spindle77 is employed herein as a convenient term-for the spindle of the threadingtool, which, it is obvious, may be a tap for cutting internal threads as well as a die for cut- In such a case, the milling-tool would be a drill to bore out the hole to be threaded, instead of a turning-down tool. The term lateral movement,77 or f lateral movementback and forth,7 is used herein in contradistinction to the intermittent rotary movement of the ordinary turret employed in screwmachines, and is not limited to a rectilinear movement in guides, which is the preferred movement, and which is therefore provided for in the machine shown, but includes a vibratory or to-and-fro movement in short arcs of a circle.
Having now fully described my said invention and the manner of carrying the same into effect, I would observe, in conclusion, that I do not claim in this application any of the improvements herein described except those which relate to the means for bringing the tools successively into operation on the rod or screw-stock, as the other improvements are reserved for my application N o. 38,250 5 but- Vhat I do claim herein isl. llhe combination, with the chuck, the series of two or more cutting-tools-such as turning, milling, or threading tools-the lateral-moving support or slide, and the series of independent longitudinal slides carrying the tools above mentioned, of automatic mechanism comprising cams and connections, or their equivalents, foroperatingsaid laterally-movin g support,to bring the several tools successively into line with the chuck, and for advancing the longitudinal tool-slides separately and in succession, substantially as described. p
2. The combination, with the hollow spindle, revolving chuck carried by said spindle, and the series of cutting-tools having longitudinal motion, of the cams and connections, or equivalent automatic mechanism, for bringing by lateralmotion said chuck and the several tools successively in line with each other, and for advancing said tools separately and in succession, substantially as described.
3. The combina-tion, with the laterally-moving tool-holder and the series of cutting-tools carried by independent slides supported in ways of said tool-holder, ofthe automaticV mechanism comprising the cams and connections, or their equivalents, for shifting said tool-holder laterally, and for reciprocating the toolslides separately and in succession, substantially as described.
In testimony whereof I have signed this specification in the presence oftwo subscribing witnesses.
ALLEN JOHNSTON.
Witnesses A. G. HARRow, J. T. HAGKWORTH.
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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2554405A (en) * 1946-07-23 1951-05-22 Peerless Tube Company Machine for internally threading collapsible tube necks

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2554405A (en) * 1946-07-23 1951-05-22 Peerless Tube Company Machine for internally threading collapsible tube necks

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