US351291A - stehli - Google Patents

Description

5 Sheets-Sheet 1. 4 J. STEHLI. MET-AL SCREW MACHINE.

(No Model.)

WITNESSES 24-05% fiww (No Model.) 5 Sheets-Sheet 2.

. J. STEHLI.

METAL SCREW MACHINE.

No. 351,291. Patented Oct. 19, 1886.

WITNESSES l/Vl/E/VTUH By 4 Afforne J N. PETiflS Piwmwm n mr, Washingion. n. c.

(No ModeL) 5 Sheets- Sheet 3. J. STEHLI. METAL SCREW MACHINE.

No. 351,291. Patented Oct. 19, 1886.

INVENTOR ATTOR EYS wgssstzs: W W2 N. FETER5. Phololilhognphln Washington. D. C

5 Sheets-Sheet 4.

J. STBHLI. METAL SCREW MACHINE.

(No Model.)-

No. 351,291; Patented Oct. 19, 1886.

WITNESSES:

ATT RIVEYS N. PETERS. PhovrLhhugnphar. Washington. a. c.

no Model.) '5 Sheets-Sheet 5.

J. STBHLI METAL SCREW MAGHINE. No. 351,291. Patented Oct. 19,1886.

Jay 0.

WIT/M8858: IIVI/EIVTOI? Mia W01 8) rrrcn.

JAKOB STEHLI, OF HARTFORD, CONNECTICUT, ASSIGNOR TO THE HART- FORD MACHINE SCREWV COMPANY, OF SAME PLACE.

M ETAL=SCREW MACHINE.

SPECIFICATION forming part of Letters Patent No. 351,291, dated October 19, 1886.

(No model.)

To all whom it may concern:

Be it known that I, JAKOB STEHLI, of Hartford, in the county of Hartford and State of Connecticut, have invented certain new and useful Improvements in Metal Screw Machines, of which the following is a specification.

This invention relates to certain improvements in the machine for making metal screws for which Letters Patent of the United States have been granted to me on July 22, 1884, No. 302,525, the improvements being designed with aview to simplify the construction of the ma chine, render the operation of the same more accurate and effective, and increase considerably the productive capacity of the machine.

Theinvention consists of a metalserew machine in which the operating elementst wit., the reciprocating carriage, the revolving mandrel with its quill and chuck, the wireholding jaws, the reducing-tool, the threadingdie, and the cutting-offtoolsare operated by a series of cams on a main shaft that is located longitudinally below the table of the machine, and by intermediate lransmitting-- levers, by which disposition of the shaft the transmitting mechanisms are considerably simplified and rendered more accurate.

The invention consists, first, of an advance cutter that works simultaneously with the cutting-off tool, wherebythe cutting off of the finished screw is accelerated and a better finish given to the head of the same. The invention consists, further, of an automatic stopmotion by which the main shaft is thrown out of gear with the power-transmitting shaft in case the wire inthe mandrel has been worked up, so that the cutting-tools are not injured by the short piece of wire in the machine.

The invention consists, further, of certain details of construction and combination of parts,- which will be more fully described hereinafter, and finally be pointed out in the claims.

In the accompanying drawings, Figure 1 represents a side elevation of my improved screw-machine, showing the mandrel and motion-transmitting worm-gear in vertical longitudinal section. Fig. 2 is a plan of the same with some of the parts shown in section. Fig. Fig. 4.

3 is an end elevation of the machine.

gitudinal bedplate, A and a horizontal table, 6

A, above which the different working parts are arranged. Below the table is supported in bearings c a of the standards A A the longitudinal main shaft B, which receives slow rotary motion by a worm.-gear-wheel transmission from a transverse shaft, B, at one end of the machine, said shaft carrying a conepulley, B, that may be thrown by a clutch mechanism and a stop-motion, to be hereinafter described, in or out of gear with the transverse shaft B, so as to automatically interrupt the transmission of power to the main shaft, and interrupt thereby the working of the machine.

On thelongitudinal shaft B are arranged eight 8 actuating-cams of different sizes and shapes, which transmit by means of intermediate transmitting lever mechanisms the required motion to the different working parts of the machine. in Fig. 1, and in detail in Figs. 7 to 14. The cams are designated by the letters a, ((1 ,60 a, a a, a and (1' according to their succession on the main shaft B, and so shaped that for each rotation of the main shaft the working parts of the machine produce a complete metal screw. The dilferent working parts are so adjusted that any size of screw within certain ranges may be made, smaller sizes of screws These cams are shown in side view 8 5 requiring a smaller machine, while larger sizes 9 5 of screws require a larger machine.

On the table A is arranged a fixed dovetailed guide-plate, A which serves to guide the correspondingly-recesscd base-plate of a reciprocating carriage, D. The carriage D supports in vertical standards D a mandrel, D The carriage D, and the mandrel D, sup

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ported thereon, are moved forward by the cam a, and a fulcrumed lever, b, which is provided at the lower end with an anti-friction roller that moves along the face of the cam a. The cam a is shown in side view in Fig. 1, in end view in Fig. 7, and in circumferential development in Fig. 7. Its face or circumference is provided with inclined parts and depressions, whereby the motion of the carriage is controlled for the purposes to be hereinafter described. The fulcrum of the lever 1) turns in bearings of the table A, which bearings project laterally beyond the table, so as to give the required steadiness of support'to the same. projecting nose, I), the threaded shank of which is screwed into a dovetailed slide-piece, If, that is guided in correspondinglydovetailed ways of an upright pillar, I), supported rigidly at one side of the carriage D, as shown in Figs. 1, 2, and 5. The slide-piece b is adjusted in the pillar b by a screw, 1), which turns in a sleeve, b, at the other end, and engages a nut on the slide-piece, as shown in Fig.

2, so as to readily raise or lower the same, ac-

cording to the length of forward motion that has to be given to the carriage, which motion corresponds to the length of screws to be made. At the upper end of the lever b is arranged a set-screw, 12 which serves to move the carriage forward to the threading-die, especially when screws of small size are to be made, so that the length of thread is regulated and the threading-die prevented from touching the re: ducing and cuttingoft tools and injuring the same. The set-screw b is properly adjusted in all cases, and has the advantage of securing the exact degree of motion of the carriage D. The forward motion of the carriagc'takes place intermittently, according to the configuration of the face of the cam a, acting on the lever b, the carriage being'first moved forward, then it dwells and moves slightly backward, when the lever arrives at the depression in the face of the cam, which receding motion takes place at the moment when the reducing-tool has accomplished its work, then forward again for forming the head, then backward, after which the carriage is held in position for cutting off the screw, it being then quickly moved back to its starting position. The return motion of the carriage is accomplished by a strong spiral spring or springs, b, that are attached. to lugs b projecting through slots of the base-plate of the carriage and table, and to fixed lugs b of the table, as shown in Fig. 1.

The mandrel D is provided with two loose pulleys, p p, and an intermediate fast pulley,

p, by which, in connection with a belt, 19, and

cross-belt 1 a forked belt-shifting lever, p, and the cam a, rotary motion is .imparted to the mandrel D" in one 'or the opposite direction. The lever 'p is operated by the cam a, which is 'fulcrumed to the lugs b below the table A, and provided at its lower end with an anti-friction roller that bears on the cir- The lever b engages near its fulcrum a of the mandrel take place as soon as the threading-die has cut the thread on the reduced shank of the screw, so as to unscrew the same from the threading-die. The return motion of the belt-shifting lever p is caused by the tension of the belts p p.

The base-plate of the carriage D is provided at one side and near its front end with a downwardly-extending piece, 8, that carries a horizontal adjustable stop, 8. The fulcru med stoplever s is operated by the cam a (shown in Figs. 1, 9, and 9,) and by a spiral spring, 8, by which the anti-friction roller at the lower end of the lever s is held in contact with the circumferential face of the cam a".

The movement of the carriage D and the operation of the tools for cutting off the screws is timed in such a manner that during the forward slidingof the carriage, and immediately before the cutting-off tools begin to perform their work the cam a will operate the stoplever s and throw the upper arm of the same downwardly into the path of the stop 8, so that the latter will strike against the upper arm of the lever s and stop the carriage until the cutting-off tools have entirely accomplished their work. The stop-lever s will then be moved up by the cam a and the action of the spring 8 out of the way of the stop 3 as shown in Fig. 1, so as to permit the carriage to move back to its starting position.

Within the mandrel D is supported a quill or sleeve, D, which is provided at the front end with a conically-tapering chuck, D, that is formed of spring-jaws which are fitted into the correspondingly-flaring end of the mandrel D. The chuck D is clamped thereby to the wire from which the screws are made, which wire is passed centrally through the quill D and held firmly in position by the IIO jaws of the chuck D, as long as the chuck is drawn into the flaring end of the mandrel by the action of two levers, d, on a shoulder, d", at the rear end of the quill- The levers df are fulcrumed to a sleeve, D of the mandrel D which sleeve is provided with slots for the levers d. The levers d extend through the slots of the sleeve to the interior of'the mandrel, and engage by projections or noses d the shoulder d at the end of the quill D. The outer ends of the levers d are engaged by the curved hub of a sleeve, (1, which slides on the mandrel D and has parallel collars d that are engaged by anti-friction rollers d at the upper forked end of a lever, (1 The lever d is fulcrumed to the base-plate of the carriage D, and

provided at its lower curved end with an anti- Lil the curved lever 11 the sleeve (1* is quickly pushed backward, whereby the levers d are 'l'QlCZlSQCTfIOIlItllO shoulder d of the quill, so that the chuck at the front end of the same is free to release thewire and slide along the same in following the backward motion of the carriage D without carrying italong. As soon as the lever d has passed the cam groove of the cam (r, the latter moves the sleeve (1" forward, so that its huh acts upon the levers d and spreads them apart, whereby the projections at theinner ends of the levers d engage the shoulder (F at the end of the quill D and move the latter backward in the mandrel D". This motion ofthe quill draws the chuck D* tightly into the flaring end of the mandrel D", so that the same rigidly clamps the wire. The cam 0?, together with its nosepiece (Z forming the cam-groove, is made of such a width as to provide for the extent of reciproeating motion of the carriage D; or, in other words, for the length of screw to be made so that the lever d can move with the carriage and operate the quill and chuck in the manner described.

Eis the reducingtool, which is accurately adjusted by set screws in a laterally-movable slide-plate E, that moves by dovetailed ways 6 on a transverse guidepicce, E of a standard, A, of the supporting-t'rame. The slideplate E is longitudinally adjustable on the dovetailed ways 0 by a screw, 6. (Shown in Figs. 1, 2, and 3.) The slide-plate E is provided with a vertically adjustable plate, E", which carries an adjustable screw, E", below the reducing-tool E, as shown in Fig. 3, so that the screw E can be adjusted higher or lower for permitting the reducing-tool to be moved back to a greater or less extent, according to the size of the head tobet'ormed 011 the screw. The slide-plate E is moved by astrong spiral spring, E in a lateral direction until stopped by an adjustable set screw, E, the spring pressing the rcducingtool E against the wire and reducing it to the required thickness of shank in conjunction with the quick rotary motion imparted thereto by the mandrel. The cam a (shown in Figs. 1, 3, and 13) operates a fulcrumed lever, c which acts by its upper end on the screw E" so as to move the reducing-tool E against the tension of the spiral spring E sidewise and out of the way of the head of the metal screw when the tool E has accomplished its work.

\Vhen the reducing-tool E has formed the shank of the metal screw, the threadingdie F is thrown into operation so as to cut the thread on the shank. The threading-die Fis attached to one end of a longitudinal sliderod, F, that is guided insl'eeves F ofa standard, F. The opposite end of the slide-rod F is acted upon by an elbow-lever, f, that is fulcrumed to the end standard, A, and operated by a cam, a (Shown in Figs. 1 and 14.)

As soon as the threading of the shank is completed, the same is released from the threading-die by the reverse motion imparted to the mandrel and wire by the shifting of the belts, upon which the lever f and the threading-die F are returned to their former positions. The carriage D is now moved back by the cam a as far as required for the thickness of the head to be formed on the screw, and then stopped and held in a stationary position by means of the stop-lever S and stop S, actuated by the cam a", as before described. The screw is now ready to be cut off from the wire, which is accomplished by an advance cutter, G, and a cutting-off tool, H, which cutters act nearly simultaneously on the wire.

The use of an advance cutter and a cuttingoff tool has the advantage that not only about one-half of the time heretofore required for cutting off the screw is saved, but also the cutter-marks which are produced by the single cutter at the center of the heads are entirely done away with and a perfectly-smooth head obtained.

The advance cutter G is operated by the cam a, a double slide-rod, g, guided in a slot, of a-standard, A a t'ulcrumed and slotted intermediate lever, 1 a connecting-link, g, which is pivoted to the lever and the ad vance cutter G, that is guided in ways 1/ of an upright standard, A On the slotted end of the lever g the slide-rod 9 can be adjusted, so that the stroke of the. advance cutter can be regulated according to the size of the heads of the screws. The guideways g of the advance cutter G are adjusted by set screws y and a swivel-screw, g, which enables the advance cutter to be set readily to the center of the wire.

The actuating mechanism of the advance cutter G and its cam a is shown clearly in Figs. 1 and 4. The cutting-off too] His located opposite to the reducing tool E on a slide plate, H, that is guided and adjusted in the same manner as the reducing-tool E. The out ting-oft tool H is also operated by the cam. (LT and t'ulcrumcd lever c, which latter moves the reducing cutter sidewise and applies then the cutting-off tool, so that it follows in the path of the advance cutter G and cuts oi't' the fur ishcd screw in a neat and smooth manner. As soon as the cuttingot'f tool H has accomplished its work,the chuck D releases the wire by the motion of the cam a and the forked lever d on the quill D", while simultaneously the end of the wire is rigidly clamped in position by a movable jaw, 1, against a fixed jaw, I, which jaws are arranged on that side 01' the standard A facing the mandrel. The movable jaw lis operated by a tulcrumed lever, 11, and the cam (6 (Shown in Figs. 1 and 4.) The upright standard A also supports a fixed guide-sleeve, K, for the wire, in front of which the reducing, advance, and 'cuttingoff tools are arranged, as shown clearly in Fig. 2, while the clamping-jaws I l are arranged at the other side of the standard A The sleeve K serves to guide the wire steadily to the reducing-tool and threading-die and to expose it to the action of the advance cutter and cutting-off tool.

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4 y l v 351,291

As soon as the carriage and mandrel are returned to their normal position, the wire-holding jaws release the wire, while the chuck at the front end of the mandrel clamps it again by the action of the cam a and lever (2 By the return-motion of the carriage the quill is moved along the wire for a length required for the next screw. The carriage is' then moved forward again by the action of the cam a, so as to complete the next screw, and so on.

In case the wire has been fed forward through the quill, until a small piece only remains, which would be held by the jaws I I, and be entirely released from the quill by the receding motion of the carriage, the next forward motion of the carriage wouldcause the chuck at the end of the quill to push the small piece of wire forward, which would then be liable to injure thecutting-off tools, as it would not be guided centrally by the quill.

To prevent injury to the cutting-tools an automatic stop -motion is provided, which, whenever the wire has been spent, throws the transverse shaft B out of gear with the conepulley B The stopmotion consists ofa drop- .pin, L, which passes through a slot of the mandrel and diametrieal slots of the quill near the chuck of the same, when the endof the wire has passed said slots. WVhile the wire is still in the quill the drop-pin L rests on the wire, as shown in Figs. 1 and 6. The drop-pin Lis supported bythe forked end of a curved lever, L, which is fulcrumed to the mandrel. D and acted upon at its other end by a spring, as shown in. Fig. 6. At the moment when the drop-pin L is dropped into the slots of the quillthat' is, at the moment when the end of the wire has passed the slots of the quillthe spring-actuated end of the lever L is forced.

in outward direction, so as to engage an arm,

L of a longitudinal rod, L", which is guided in bearings ll of the base-plate ofthe carriage D, as shown in Figs. 2 and 6. The rod L extends over the transverse shaft B, and is provided at that end with-a second arm, Z, that is thrown into line with a set'screw, Z, of an oscillating arm, L when the oscillating arm L is struck by the end of the lever Z. The oscillating arm L is hinged to the end standard, A, of the supporting-frame A, and retained in upright position by the pressure of a crosspin, Z, of a transverse rod, L, that is guided in lugs Z" of the frame A, and provided with a collar, Z. The rod L is acted upon by a strong spiral spring, Z, which is interposed between the collar Z" and one of the lugs Z, as shown in Fig.2. Atthe momentwhen the arm L pushes the oscillating arm L back, so that the latter clears the cross-pin Z", the spiral spring Z forces the transverse rod L sidewise. A lug, l, at

the end of the rod Z, engages a collar of the eonepulley B so as tomove the latter sidewise on the shaft B, and throw it by a suitable clutch mechanism out of gear with the same. The machine is then instantly stopped, as no motion is transmitted to the main shaft. The attendant has to insert anew wire into the quill, upon which the work of the machine is resumed.

The stop-motion forms an essential feature of my improved machine, as thereby the ma chine .is protected against injury by careless and inattentive workmen.

The operation of the machine is as follows: The carriage D is moved forward by the action of the cam a and lever 12, as hereinbefore described, and thereby the wire fed forward. Simultaneously the quill D tightly clamps the wire by the action of the cam a and lever (1 so that both rotate with the mandrel D By the forward motion of the wire the same is exposed to the action of the reducing-tool E,

operated by the cam a and the shank formed thereby exposed to the action of the threadingdie F, operated by the cam a As soon as the thread has been cut on the reduced shank, the motion of the mandrel is reversed, so that the shank is unscrewed from" the threading-die, which then drops back. The carriage and its wire are next moved backward by the action of the cam a for the distance of the head of the screw, and locked stationary in position by the stop 8 and stop-levers, operated by the cam a In this position the advance cutter G and the cutting-off tool H operate upon the threaded wire by means of the cams a and a so as to cut off the screw without nick or blemish on the head. The clamping-jaws I I are then applied to the wire by the action of the cam (1?, said jaws holding the wire rigidly in position. The stop-lever will release the carriage D, so that the same can be moved back. Simultaneously the quill will release the wire by the action of the cam a and the lever d on the levers (1, so that the quill can ing small metal screws of all kinds used in the manufacture of watches. It can also be used for making pinions and balance-shafts,in which case the threading mechanism is dispensed with, while the reducing and cutting tools perform the same functions; also, by substituting a suitable drilling-tool in place of the threading-die, hollow shafts or collars can be made on the machine.

Having thus described inyinvention, I claim as new and desire to secure by Letters Patent 1. The combination of a-longitudinally-reciprocating carriage, a rotary mandrel'supported by said carriage, a quill within said mandrel adapted to clamp the wire, and the reducing,'threading, advance-cutting, and cutting-off mechanisms, substantially as set forth.

2. Thecombination of a carriage, means for reciprocating the same, a rotary mandrel supported by said carriage, a quill within said mandrel, mechanism for reciprocating said quill independently of the mandrel, a reducing-tool, a threading-die, an advance cutter, a cutting-off tool, and mechanism for actuating said tools, substantially as set forth.

3. The combination of a longitudinally-reciprocating carriage, a rotary mandrel supported by the same, an independent] y-reciprocatin g quill within said mandrel, mechanism for rotating and reversing the mandrel, and the reducing, threading, advancecutting, and cutting-off mechanisms, substantially as set forth.

4. The combination of a longitudinally-reciprocating carriage, a rotary hollow mandrel supported by said carriage,a wire-gnidi ng quill within said mandrel adapted to reciprocate in said mandrel and independently therefrom, mechanisms for turning down, threading, advance-cutting, and cutting off the screw, jaws for clamping the wire after the screw has been cut off, and a longitudinal cam-shaft having cams for actuating said. mechanisms, substantially as set forth.

The combination of the main shaft B, cam a,fnlcru1ned lever I), having setscrew I), carriage D, having a projecting nose,b, and mechanism for vertically adjusting thesame,whereby the extent of motion of the carriage is regulated, substantially as set forth.

6. The combination of the rotary main shaft B, having cam a and nose (Z fulcrumed lever al having a forked upper end, a rotary mandrel, D a sliding sleeve, (1, having curved hub and collar 11", an interior quill, D, having a chuck, D", at one end and a shoulder, (1 at the opposite end, and levers d, fulcrumed to a sleeve of the mandrel, and having interior noses, d, engaging the shoulder d, so as to move the quill independently of the mandrel, substantially as set forth.

7. The combination of the longitudinalmain shaft B,having cam a, a fulcrumed and springactuated stop -lever, s, and a reciprocating carriage, D, having an adjustable stop device, s", at one side thereof, substantially as set forth.

8. The combination ofthe longitudinal main shaft B, a cam, a, with the longitudinally reciprocating carriage D, a mandrel, D supported by the carriage, a fast pulley, p, and loose pulleys p on said mandrel, a fulcrumed 1everpflhaving belt-shifting devices at the upper end, and a belt and cross-belt, p 1), engaged by said beltshifting device, so as to impart a rotary motion to the mandrel and reverse the same at the proper moment, substantially as set forth.

9. The combination of the main shaft B, having a cam, a, a fulcrumed lever, i, a movable wire'clamping jaw, I, at the upper end of the lever i, and a fixed jaw, I, supported on an upright standard, A substantially as set forth.

10. The combination ofthelongitudinal main shaft B, cam a fulcrumed lever 0 an. upright standard. A, laterally -reciprocating slide-plates E H, spring E reducing-tool E, and cutting-off tool H, supported by said slide plates, and setscrews E and E, substantially as set forth.

11. The combination of the main shaft B, adjustable slider-0d g, upright standard A having slots 9 and ways 9, fulcrumed and slotted lever g, connectinglink g", and a laterally-adj nstable advance cutter, G, guided in the ways 9, substantially as set forth.

12. The combination of a longitudinallyreciprocating carriage having a mandrel supported on said carriage, an independentlyrcciprocating quill within said mandrel, mech anisms for reducing, threading, and cutting off the screw, and a stop-moti0n connecting the mandrel and quill with the clutch mechanism on the driving-shaft, so as to stop the motion of the machine whenever the end of the wire leaves the quill, substantially as set forth.

13. The combination of a reciprocating earriage, D, a mandrel, D, supported by said can riage, an interior independently-reciprocating quill, D, a drop-pin, L, passing through slots of the mandrel and quill, a spring-actuated lever, L, fulcrumed to the mandrel and engaging the drop-pin L, a longitudinal rod, L having arms L and Z, a hinged arm, L,

having a set-screw, Z, and a transverselyguided and spring-actuated shaft, L having cross-pin Z and lug Z the latter engaging the clutch of the driving-shaft, substantially as set forth.

In testimony that I claim the foregoing as my invention I have signed my name in presence of two subscribing witnesses.

JAKOB STEHLI.

\Vitnesses:

A. OATMAN, G120. M. Bonn.

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