US2130373A - Template follower - Google Patents

Description

Sept. 20., 1938.

J. L. ANDERSON TEMPLATE FOLLOWER Filed July 10, 1937 INVENTQR A V ATTORNEY Patented Sept. 20, 1938 PAT ENT" 6F I CJE I TEIVIPIJATE 'FOLLOWER.

James L. Andersonpclosteni N. J., assignor to AirLReduction Company, Incorporated, I New York, N Y.-,

a corporation of New-York Application-July 10, 1937, Serial No. 152,958

17-- Claims; (Cl.:3323) inventionrelates to terripl'ate followers.

It*i'sanobj'ec't of the invention'to. provide an" improved;template-follower which automatically follows"ternplates'- of irregular .shape' including curves-"of rela'tively' "short" radii. The invention comprisesnovel features"and combinations of" elements which make the template-follower simple and -econoinical to manufactureand convenient to use.

In a'ccordancewith onefeatur'e of theinvention a follower rolleroiraninclined axis rests on the top face-of a-templat'e and is driven to cause it to travel along thetemplate; andguide means are-provided"for 'causing the" follower roller to stay*-on=' me-- top face" of 1 the template around curves-in eitherdirection as wellas along straight run's Another objectof theinvention" isto prevent the guide means from' binding against the side's' o'f t e"=tem'plate"o n"sharp curves.

Othe'r oh ct's,*fea'tnres and advantages of the inventionwill appear 'or -be pointe'd out as the speeification proceeds.

In the accompanyingdrawing', forming part Fig;- 1 i's as'ectibnal view of a template-follower emliiodt ihg the inventionr c "is an elevation of thelowerpart of the template -follower of' Fig. 1, looking toward the" to Fig?" 'biitshowing a'modified"form of the invent'io Fig'si l and 5 am elevations of other modified forms of the invention.

bracket :l Q'iwi'th a -s'crew -I l barlc'fl'niof machines 1 for clamping it to a avin' foldi-n'g parallelogram frames the torch is s'upported fr'om theiront-bar and partakes of the same mover-menta's atracer or template-follower clamped to the bar. The inventionristnoh 'limit'ed' to -machlnes of the foldingsleeve rlfi 'isfreekto slide up'and down in'the bearing ilfi-"for a limited distance butis prevented frOn-i turning Icyiarack I! which is fastened to thesl'eeve by'scre'ws I8 and extends into a slot'l'9 in the bracket ID. This slot is inefiect a keyw'ay 'andthe rack IT a key to prevent the sleeve-from: rotating, buttheslot I9 is longer Fig. :3 is 'a---frag-mentary* sectional view similar universal cutting machine." With than the rack so that the sleeve can move up and downa ,A pinion, 2d,. on an axle 22 rotated, by a handwliee'l' 23',lmeshes With the rack I T and serves to" loweraridf raise thesleev'e I51 when the'template-fcnower ist'o be moved into or out. of Contact withia template. The upper part of the t'e'mpla'te-follcrv've'ris similar to known tracers and aidescript'ioniof itis'not necessary'fora c'omplet'ei understanding of this" invention; Tracers of suchfconstructi'onlar'e'zshown in Patent No. 2,059,755; dated November 3, 1'936;.and Patent N0. 1,999,'5,"dated April 30, 193 5.

The lower end of the sleeve i5 is of reduced diameter andextends'iint'o a housing or frame 25. 'Theupper end of theirame 25 has a sloping annular. faceviihi'c'h contacts with an undercut shoulderZB on'the'sl'eeve; The housing or frame 25 rotates on .thesleev'e l5 as a bearing and the outs'ideof the upwardly] extending end of the frame 25*fo'rms a continuation of the outside surface of the'sl'e'evei l'5which s'lides'in the bearing'l' v'i During" operation" of the template-followerthesle'eve l 5=and"frame M are free to move up and do'wn with afloating'action'inresponse'to anyirregularities in the supporting surface along whi'chthe template=follower runs? A-'ternplate-follower roller 2'l. is secured to the end 'of a slopingaxle 28"that rotates in anti-' frictioirbearings" 29;3011'eld by the frame 25.? A bevel gear 32 keyed to the axle 28 near its upper end meshes" with a bevel gear 33 fastenedto" the lower end" of" drive' shaft 35:

The frame 25' a'nd"sleevel 5 are 'held assembled by ai-collar 3 6bn the" drive shaft "351 Thiscollar supportsa bal libearing' 33 inwhich the shaft 3 5'. turri's and-"the ball' bearing thrusts against a shoulder 34 lathe-frame 2'5 and keeps the'upper'" end' 'of"-the"framein"coritact; or substantially. so, with the undercut" sho'uld'e'r' "26 "of' the sleeve;

The xis-cf rotation of the'frame 25 about the sleeve 6'5"is coihcident'with"theaxis of the drive shaft 35, and the point oftractionof the roller 21 on-a'te'mmate -3lisin line wit'htheaxisof the shaft? 35.- Y

The roller 21' is prevented-from running oiT the. top face ofthe template 37by'guide means which includesa'lowerguide roller '39, atv the end of the anew in position 'to*contact withone side of the template, and two other: guide rollers or" wheels that contact with'the other side? of the" template. The guideroller. 39"is'pre'ferably in"- .tegrarwith'the roller 21 and axle 28'but ma -pa an idler rotatable independently. of the roller 21; andaxle '28i' Inan'y' event some slippage of the peripher'yo'f the guide roller 39 on the side' of the Cir template will occur because the different points on the surface of the guide roller are not equidistant from its axis of rotation and therefore travel at different velocities when the guide roller turns. This slipping is not objectionable, however, because the guide roller does not support the weight of the template-follower and has relatively light contact with the template.

The wheels 49 are preferably idlers and are supported by screws 4| from a swivel member 42 which turns about a vertical screw 44 threaded into the oblique bottom face of a rod 45. That part of each of the screws 4| just above the head of the screw comprises the axle for the wheel 40 supported by that screw, and the large fiat head of each screw 4| serves as the thrust bearing which supports the weight of the wheel 4!). Rotary means driven by power can be employed in place of the wheels 40, but the additional traction obtained in this manner is unnecessary with most machines on which the template-follower of this invention is used.

The rod slides longitudinally in an inclined bore in the frame 25 but is prevented from turning by a pin 41 which is fixed to the frame 25 and extends through a slot 48 in the rod 45. A coil spring is pressed against the upper end of the rod 45 by a screw 5| which threads into the upper end of the bore in which the rod 45 slides. The pressure of the spring 50 yieldably holds the wheels 40 against the side of the template, and the reaction of the spring against the screw 5| acts through the frame 25 and urges the guide roller 39 against the template.

.One of the wheels 40 contacts with the template a short distance ahead of the point of traction of the roller 21 on the template, and the other wheel 40 touches the template some distance behind the point of traction. The distance between the wheels 40 is made short so that the template-follower can turn curves of short radii. The spring 50 makes it possible for the wheels 40 to move either way, depending upon whether they are on the inside or outside of a curve, to allow for the curvature of the arc of the template between the Wheels 40. The guide roller 39 has line contact with the template along a vertical line and therefore does not bind when passing around sharp curves, as is the case with ordinary flanged wheels.

A slight speeding up or slowing down of the template-follower of Fig. 1 occurs when it turns sharp curves because of the epicyclic effect when the gear 32 rolls around the driving gear 33. The epicyclic effect causes the speed of the templatefollower to increase when the gear 32 rolls in the same direction that it is turning, and to slow down when the gear rolls in the opposite direction. This variation in speed is not enough to be objectionable with ordinary work, but when very uniform speed is essential it can be obtained with the structure shown in Fig. 3.

The upper, broken away portion of the template-follower shown in Fig. 3 is the same as that shown in Fig. 1, but in Fig. 3 a frame 25' is slightly different in shape from the frame 25 of Fig. 1 to allow for a different location of bearings. Wheels 41' are supported from. a swivel member 42 at the end of a rod 45 which slides in the frame 25. The parts in Fig. 3 that correspond with parts in Fig. 1 are indicated by the same reference character with a prime appended.

A worm 54 at the lower end of a drive shaft 35' drives a worm gear 55 secured to a shaft 56 journaled in the frame 25'. A bevel gear 58 on the shaft 56 meshes with a gear 59 at the upper end of an axle 28' to transmit rotation of the shaft 56 to the axle 28'.

Ball bearings 29 and 30' hold the axle 28' at an inclination and there are a traction roller 21' and a guide roller 39' at the lower end of the axle. When turning sharp curves with the modified form of the invention shown in Fig. 3 there is substantially no epicyclic effect to increase or decrease the speed of the roller 21'. If the frame 25 makes a turn of ninety degrees, the only movement of the gear 58 caused by the turning is a rotation through an angle corresponding to onequarter of the distance between teeth of the worm gear 55, and the angular movement of the rollers 21 and 39 is only slightly more, depending on the ratio of the gears 58, 59.

Fig. 4 shows a modified roller assembly which makes it unnecessary to have the wheels 40 to keep the traction roller on the template. In addition to a traction roller 52 and a guide roller 63 corresponding to the rollers 21. and 39, re-

, spectively, of Fig. 1, another guide roller 65 is connected with the axle in position to contact with the side of the template remote from the roller 63. Since the guide roller 53 prevents the traction roller 62 from running off the template ,to the left and the guide roller 65 prevents the traction roller from running off to the right, the wheels 40 are no longer necessary.

Fig. 5 shows a template 69 which has a groove along its top face, and a traction roller H runs in this groove as shown in the drawing. This groove gives the roller greater friction contact with the template, and it keeps the roller from being displaced laterally of the template when the follower is not in operation. When the roller H is driven to cause the follower to travel along the template, the frame and other structure to which the template-follower is connected and for which it furnishes the motive power has friction in its bearings and offers resistance to the movement of the template-follower. As a result of this resistance the .gear 32 (Fig. 1) tends to ro-g tate around the driving gear 33 to turn the frame 25 about its axis. Such a turning of the frame would cause the roller H (Fig. 5) to climb out of the groove in the template 69, but such movement of the traction vrolleris prevented by a guide roller 13 which is similar in construction to the guide rollers 39 and 63 employed with the embodiments of the invention shown in Figs. 1 and 4. I

It will be understood that terms of orientation used in the description and claims are relative. The invention is not limited to the embodiments illustrated and some features can be used without others without departing from the invention as defined in the claims.

I claim? 1. A template-follower for a universal cutting or welding machine including in combination a roller for contact with a template, an axle about which the roller turns, said axle having a substantial inclination so that the roller tends to travel transversely of the template, a frame holding the axle, and a bearing on which the frame rotates, about an axis in line with a point of contact of the roller on the template, to change the direction of travel of the template-follower.

2. In a template-follower, a frame rotatable about a vertical axis to steer the template-follower, anaxle carried by the frame, a roller on the axle in position to contact with a template at a point in line with the axis of rotation of said frame, the axle being at a substantial, acute guide roller connected with the first roller in posi-' tion to contact with a side of the template when the first roller is operating along the top. face of the template. a

3. In a template-follower,a frame and a bearing on which the frame turns as the template follower changes its direction of travel, an in clined axle carried by the frame, a template-follower roller on the axle in position to contact with the top of a template at a pointin'line with the axis of rotation of the frame, a second roller on said inclined axle in position to contact with one side of the template and serve as a guide to confine movement of said template-follower roller transversely of the top face of the template, and means for holding the second roller against the template.

4. In a template-follower, a frame and a bearing on which the frame turns as the templatefollower changes its direction of travel, an inclined axle carried by the frame, a template-follower roller on the axle in position to contact with the top of a template at a point in line with the axis of rotation of the frame, and two guide rollers on the axle in position to contact with opposite sides of the template to prevent displacement of the template-follower roller transversely of the template.

5. In a template-follower for cooperation with a template having a longitudinally recessed top face, a traction roller having a face which fits into the recess of the template, an axle for said traction roller, the axle being inclined with respect to the template so that the traction roller tends to climb out of the recess toward one side of the template, and a guide roller connected with the traction roller in position to contact with the other side of the template to prevent the roller from moving out of the recess.

6. A template-follower including a traction roller which runs on the top face of a template, a guide roller attached to the traction roller in position to contact with a side of the template and prevent transverse displacement of the traction roller, and yielding means which hold the guide roller against the template.

7. A template-follower including a traction roller which runs on the top face of a template,

a guide roller attached to the traction roller in position to contact with a side of the template and prevent transverse displacement of the traction roller, a second guide roller which contacts with the other side of the template, and yielding means for urging said second guide roller against the side of the template.

8. A template-follower including a traction roller constructed and arranged to travel along the top face of a template and having a guide roller directly connected with the traction roller and located in position to contact with one side of the template at a set distance from the traction rollerytwo wheels in positions to contact with the side of the template away from the guide roller at points slightly ahead of and slightly behind the line of contact of the traction roller and its guide roller with the template, and means urging the wheels toward the guide roller to hold said wheels and guide roller in contact with opposite sides of the template.

9. A template-follower comprising a frame, an axle carried by the frame, a traction roller on the axle in position to contact with and travel along the top face of a template and having a guide roller attached to the traction roller in position to contact with one side of the template, two wheels :in positions to contact with the side of the template away-from the guide roller at points slightly ahead of and slightly behind the lineof contact of the tractionroller and its guide roller with the template, a support for said wheels,

and a swivel connection between said support and the frame.

10. In a template-follower, a vertical drive shaft, a frame, a bearing onwhich the frame turns about the axis of the drive shaft, an inclined axle in the frame, a template follower roller on the axle with the low point of the roller in line with the axis of rotation of the frame,

said axle having a substantial inclination sothat the roller tends to travel transversely of the template, guide means for preventing transverse movement of the roller on the template, and motion transmitting connections between the drive shaft and the roller.

11. In a template-follower, a vertical drive shaft, a frame, a bearing on which the frame turns about the axis of the drive shaft, an inclined axle in the frame, bearings in the frame in which said axle rotates, a roller secured to the axle at a location which puts the lowest point of the roller in line with the axis of rotation of the frame, said axle having a substantial inclina tion so that the roller tends to travel transversely of the template, guide means which prevent the roller from running transversely and which hold said roller on the top surface of the template, and gearing connecting the drive shaft with the axle.

12. In a template-follower, a vertical drive shaft, a frame, a bearing on which the frame turns with respect to the drive shaft and about the axis of the drive shaft as the templatefollower changes its direction of travel, an inclined axle in the frame, bearings in the frame in which said axle rotates, a roller secured to the axle at a location which puts the lowest point of the roller in line with the axis of rotation of the frame, said axle having a substantial inclination so that the roller tends to travel transversely of the template, guide means which prevent the roller from running transversely and which hold said roller on the top surface of the template, and gearing connecting the drive shaft with the axle, said gearing including a worm on the drive shaft operating a worm wheel which has its axle supported by the frame.

13. A template-follower including a traction roller supported for rotation about an axis which has a substantial inclination, means for maintaining the roller in contact with a template and the incline of the axis in a definite relation to the template, said incline being sufiicient to make the roller tend to move transversely of the template, and apparatus for driving the traction roller.

14. A template-follower including a frame, a bearing on which the frame turns about a substantially vertical axis, an axle held in the frame, a traction roller on the axle constructed and arranged to contact with a template, said axle having a substantial inclination so that the roller tends to travel transversely of the template,

means holding the traction roller against trans means connected withythe traction roller for.

rotating 'said roller.

,:115.'A template-follower including a frame, a

bearing onwhich -the frameturns about .a sub-- 1 stantiallyvvertical axis, an inclined axle held in the frame, roller means on the axle in position to contact with a supporting surface and with from turning except'in accordance with turns in the template.

16;.An automatic template-follower including aroller having afacewhich bears against a guidinglsurface of a template,and having a friction face :constructedland arranged to bear against a surface which'isat an inclination to the axis of rotation of the "roller to produce a tractive force having a component toward the'guiding surface of the. template,.and power means for rotating the roller.

1'7. In a template-follower, an inclined axle, and a roller on=the axle with two contact faces in such relation that one face rolls along an upstanding guidingxedgeof a template while the other l-faceisupports the roller from a substantially horizontal surface and supplies tractive force to the template-follower with a component of the tractive foroem'ging the roller toward. the guidingedge of the template.

JAMES L. ANDERSON.

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