US2345494A - Spar tapering and shaping machine - Google Patents

Description

March 28, 1944. R, F, QNSRUD 2,345,494

SPAR TAPERING AND SHAPING MACHINE Filed Dec. 29, 1941 '7 Sheets-Sheet 1 @faz/agg! I @MMSM March 28, 1944.` A R. F. oNsRuD 2,345,494

SPAR TAPERING AND SHAPING MACHINE Filed Dec. 29, 1941 7 Sheets-Sheet 2 March 28, 1944. R, F, QNSRUD .2,345,494

SPAR TAPERING AND SHAPING MACHINE Filed Dec. 29. 1941 7 Sheets-Sheet 3 l Z'Egg O 'r il 34 l 49 33 I I 24 i| l I l i l 50 ,-5 l 12:53 2.@ *1.1

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March 28, 1944. R, F ONSRUD 2,345,494

SPAR TAPERING AND SHAPING MACHINE Filed Dec. 29, 1941 '7 Sheets-Sheet 4 9 7:"4, ,/@-fa l /0 ZZ W sa sa sa sa Q sa I Marck 2s, 1944. R. F. ONSRUD' 2,345,494

SPAR TAPERING AND SHAPING MACHINE Filed Dec. 29, 1941 7 Sheets-Sheet 5 3 @MA MSM; 4

SPAR TAPERING AND SHAPING MACHINE Filed Dec. 29, 1941 '7 Sheets-Sheet 6 March 28, 1944. R. F. oNsRuD SPAR TAPERING AND SHAPING MACHINE 7. Sheets-Sheet 7 Filed Dec. 29, 1941 Patented Mar. 28, 1944 UNITED STATES PATENT OFFICE SPAR TAPERING AND SHAPING MACHINE Rudolph F. Onsrud, Chicago, Ill., assignor to Onsrud Machine Works, Inc., Chicago, Ill., a corporation of Illinois Application December 29, 1941, Serial No. 424,797

13 Claims.

The machine herein illustrated and described is designed particularly for doing forming work on extruded or drawn beams or spars of various uniform sections such as angles, Us, Is, Hs, etc. In particular, the machine is intended to take care of the surfacing and vtaperingof the main structural elements of aircraft wings and bodies wherein it is desirableto use beams or spars of aluminum and magnesium alloys of a length sometimes equal to awing length or the entire wing span of the craft. A spar for example of U orr H section, uniform in crosswise measurement throughout its length, must be tapered and lightened towardsone or` both ends and otherwise shaped along `its sides, ready to intert with other structural elements secured thereto. Such spars are quite flexible and require to be clamped to thework support `at frequentintervals. In this machine the `wort: support isa long and heavy table forming a track for a cutting head carriage. The` base or bed and table of the machine is divided into lengthwise sections so that according to the number ofv base sections any one machine is adapted to meet the requirements for forming airplane spars, regardless of the length thereof. It is'also' desirable to prof vide a machine of this classwhich is open-sided, so that thearticles operated upon may be loaded sideways on to the machine table.

4 Among the chief purposes of the invention. isi

that of improving the mounting of individual cutter driving motors, wherein these motors Aand the cutters carried thereby are movable in var' ious directions as determined by form-regulating pattern or template bars, yet irrespective of the required changing position of the motorsrwhile atwork, the cuts are performed with a steady, sure operation. The particular manner of mounting the cutting motors or heads on a traveling carriage is, therefore, Aone of the" main" merits of this machine.

Y The objects of the invention are'attainedby means of a machine as illustrated in thedrawings, wherein:

- Figure 1 is a Iperspective view of the machine with the stationary part, alonglwhich Varioper-v ating carriage travels, `shown broken away, duel to its length;

Fig. 2 is an enlarged transverse sectionalview illustrating the carriagedrive and the. construe; tion and mounting of one of thev cutting headsy wherein the tool-carrying spindle turns ongV an axis which maybe .inclined from vertical ,and

the,V cutter-operated thereby works on theone sideof aspariorrbeani; 1

Fig. 3 is a face view, partly in section and broken away, of the subject matter of Fig. 2;

Fig. 4 is a plan view of the construction shown in elevation by Figs. 2 and 3; Y

Fig 5 is an enlarged sectional detail as indicated by the line 5-5 on Fig. 4, illustrating the construction and mounting of a supporting arm for the cutter head illustrated in Figs. 2, 3 and 4;

Fig. 6 is an enlarged detail in elevation to illustrate the structure and operation of one of the stationary work clamps; I

Fig. 7 isa fragmentary view in elevation of the carriage drive mechanism. i

Fig. 8 is a perspective view of the ,operators platform and control side of the machine.

Fig. 9 is a fragmentary plan view of a travelling work-holding or clamp means, attached to the tool carriage. l

Fig. 10 is a side view of the construction shown by Fig. 9. l Fig. 11 is an enlarged transverse sectional detail of part of the equipment of Fig. 9, and includes in section, the work operated upon, a forming bar and guide roller.

.Y The general arrangement of this machine as indicated above is a long stationary base or table for supporting spa-rs and the travelling carriage which rides along one side of the table and carries a plurality of cutting units for shaping three sides of spars. The driving motor for the travelling carriage and the cutting head motors are all electric and mounted upon the travelling carriage and receive power from an overhead trolley.

Reference numeration appearing upon Figs. 1, 2, 3, 7 Aand 8 of the drawings refer to elementsV of the machine corresponding to numbers given the following paragraphs, 1-40 inclusive: l

l. The bed of the machine is formed by a plurality of sections, each of approximately15 feet in length and secured at its ends to adjacent sections to provide the machine with a work rest of any desired length. Each section rests on wide supports.

v2. The table is of the open-grate type to permit cuttings to fall to a conveyor located inside and at the bottom of the bed. As shown in the drawings, the table is provided with transverse fixture-receiving y T-slots which arel located 9 inches apart.

3. This numeral refers to slideways` or tracks formed on the bed for receiving and supporting the travelling carriage upon which the cutting heads are mounted. The track construction is closely ground, as are the coacting carriage ,surfaces to minimize vibration.

li. This numeral indicates a former bar detachably secured to the table top and which regulates the operation of a plurality of cutting heads working on different surfaces of a spar secured to the table.

5. The travelling carriage carrying the cutting units and which in its operating stroke travels to the left, Fig-1. f

6. This indicates generally the trolley arrangement set to allow for overhead clearance and arranged to carry currents of diiierent frequencies as required for the motors of the machine, including tool-operating motors and motors for feeding the carriage and for driving an air-coni-l pressor and cooling pump,` all mounted on the travelling carriage.

1 is a conveyor for removing chips from the machine.

8. Swivel work securing clamps are regularly spaced along the table. Each clamp exerts approximately' pounds pressure and the clamps are operated in groups-under thecontrol of handoperated-Valves. J

9. This is a watercooled,`electric motor carrying a. surface cutter on `a horizontal axis and is mounted fcfrf-l'iancll adjustment laterally of the carriage and for automatic up-and-down movement as determinedby a roller engaging a xed form bar. Y Y

lil.y The cutter isfcarried by an arbor, driven direct by the motor. f v

Il isa heavy pivoted yokev in which the motor 9 is carried with provision for lateral adjustment.

I2. -(Fig. 7). A `Variable drive connection between the carriage-operatingmotor and carriagey drivepinion for the-purpose of varying the vfeed of the carriage according to the depth of the cut.

I3. A rack fixed to the machine bed and with which the carriage drive pinion meshes.

lei. The operators platform as located on the carriage provides for-convenient reach Vof the air and electrical controls-i I5. A motor driven pump is provided for circulating cooling iiuid through va water jacket for motor 9 and from there to the cutter IG. The cooling fluid takes the chips away-from the Cutter..

' le. A nozzle for rapidly directing the flow of cooling and chip removing -fluid to the cutter.

ll. This is a `filterl for the coolingV fluid.

l.' An air-compressor which is also watercooled.l Y Y i9. This is atank in which air at somewhat over 100 pounds pressure is stored. Airpressure isused-to hold" the cutting tools in Yand out ofV operative position',

2G indicates a spar or beam clamped on the table 'in position for operations performed thereon. n

2l.- issa roller guide for the horizontal cutting unit which` mills the-top side of'material worked- OIL. v f.

22. This is a housing and outboard bearing for horizontal cutterv l and also serves toy yprotect the horizontalhead guide roller 2l from'c'hips.

23.- A take-up screw is used for adjusting the height of the guide roller to compensate for reduction of the cutterl Adiameter due to resharpening.

2li;y 25 and 26Y are -double-acting air cylinders for respectively raising and lowering thehorizontal -cutter` head and! for "raising and lowering cutter heads whichV operate upon the sides of a spar, or beamyon -axes substantially atl rightangles to the horizontal cutting head.

yangle or used in connection with a former bar for the purpose of milling a twist or warped surface Von the sides of beams.

K 3l represents air valves, each of which controls the operation of a set of work-securing air clamps 8. There is usually six of these clamps to a bank.

32 indicates push buttons for starting and stopping ail motors from the front of the machine as convenient in setting up adjustments of the machine for a particular class of work.

33 and 3d are air cylinders respectively used for resiliently controlling side movement and angularity of the vertical motors.

v 35 indicates cutters driven by the vertical motors.

36 and 3i' are guide rollers for the vertical cutter heads. V-

38 'and 39 'designate parallel supporting arms for the vertical cutter heads.

40. This numeral indicates various valve controlled conduits for the supply and release of air on opposite sides of the various air cylinders which determine motor positions and the pressure of guide rollers of different cutting unitsr against the-forming bars which serve to regulate the depths and forms of cuts. Y Y

The above list of parts,Y while serving to disclose rthe location, function and arrangement of different working parts of the machine does not include detailed reference to the specic constructions of the mechanical combinations to which the claims are directed. The latter are drawn mainly to the means for movab-ly supporting the vertical and horizontall cutting heads in this open-sided millingmachine; but before giving a detailed description of such cutting head mountings, reference will be made briefly to the drivev mechanism of the machine.

The drive motor 4I for carriage 5, Fig. f7, is coupled with pinion 42 on the carriage which meshes with a spirally toothed rack xed to the bed of the machine. The drive connection l2 includes a variable speed belt and pulley arrangement 44, reduction gearing 45' including the worm and wormwheel connected with pinion 42. The feed of thev carriage along the bed of the machine is regulated in speed inversely to the quantity of material removed from the spai's or beams operated upon and such speed` is generally variable during the working stroke of the carriage. rIfhe return travel ofthe carriage is preferably made at a fasterfrate. Change in drive ratio is eifected lby oscillating motor il on pivot46. This is done through pneumatic cylinder 4l under valve control. 1

i The principal features of improvement in this machineY are 1in the construction ofthe supporting and controlling means, for what is termed.v herein vertical cutting umts, meaning those carrying cuttingtools for rotation on a more or less vertical axis. varied according-to. the surfa'ce'angles required on portions or the' work operated upon. Yet it is important that such surfaces be accurately formed tospecied dimensions and smoothly, so as not to require any further riishing opera- 'Ihe axis ofrthe tool may be'` tions. It is, therefore, necessary to provide a exible mounting for these cutting heads with joints to allow all necessary movements thereof but still insure a construction which remains steady and free from `vibration during operation of the cutting heads.

Figs. 3, 4 and 5 illustrate the manner in which the vertically disposed cutting units 28 and 29 are mounted. One of these cutting units is used for shaping one side of a spar and the other for shaping the opposite side, and they rotate in opposite directions.l The vertical cutting units operate at the same time or singly, depending upon the nature of the work and in cooperation with the cutter I which sets on a horizontal axis. The vertical cutting units 28 and 29 are mounted for automatic movement-laterally toward and away. fromthe work Yand for movement in a vertical direction and also for oscillation on a horizontal axis. Lateral movement of these cutting units toward and away from the sides of the spar is effected by. and against pneumatic pressure in double-acting cylinders 33.

As shown by Fig. 4, the piston rod 48 for cylinder 33 is pivoted to an arm 49 fast on shaft 50 which carries the arm structure 39 parallel with arm`38. When arm 39 is oscillated one of the vertical cutting units is shifted laterally. The cutting units is carried by the heavy link construction l connecting the outer ends of arm 38 and 39. A slide 52 is dovetailed into element 5| as shown in Fig. 5, to allow for initial lateral adjustment of motor 29, relative to element 5l. The slide 52 has a cylindrical ange 53 upon which is rotatably mounted pivot block 3U `into which the motor frame is dovetailed to permit vertical movement of motor 29, relative-to its support. v

The motor is either clamped in fixed position on the pivot block, or is cammed upwardly, relative thereto in the processing of work by means of roller 35, Fig. l. The former bar 4 has' cam surfaces for controlling vertical adjustment of the cutting unit through roller 36. The sides of this bar also have cam surfaces for engagement with roller 3l, in order to effect lateral shifting ofthe cutting unit against pressure in cylinder 33. 4

- Pivotal adjustment of a cutting unit on a pivot block 30 may be effected automatically by means of a construction as shown in Fig. 2, wherein the cutting unit is shown as provided with a roller 54 which engages one side of the former bar and operates against pressure in cylinder 34. When a uniform angular cut is made throughout the length of a spar, the motor may be permanently set onits pivotblock 36 by tightening up on clamp screws 55, Fig. 2.

The means for holding the work operated upon against movement consists of a plurality of sets of clamping devices such as illustrated by Fig. 6, which clamping devices are mounted upon the work-receiving table as at 8, Fig. l, and another work-securing means consisting of astructure which travels with carriageY 5 and is illustrated in detail by Figs. 9, and ll. f f

The pneumatic clamp construction shown -in Fig. 6 consists in the reciprocating grip devices .8V operated by armsl'having stationary pivots 51 and with the movable ends pivotally connected at 58 toA the `piston of an air cylinder 59. The pistons operate against the pressure of lifting spring 60, and therefore,the operation of these clamps is effected by 1etting air inf 'andout' of ai series of;

cylinders 59. The vertical reciprocating part 6| of each clamp carries a collar 62 having a bayonet slot 63 engaging a stationary pin 64 for the purpose of oscillating the clamping arms away from the work on the upstroke of the clamps so that the work operated upon may be lifted vertically with ample clearance before the work is shifted laterally out of the machine.

The traveling clamp construction indicated in plan by Fig. 9 provides steadying rollers for the work adjacent one of the cutting tools as l D indicated in this figure. This traveling clamp device is connected to carriage 5 by a bracket S5, and has guide rollers 63 for engaging tracks 51 bolted to the table. Spring-actuated pressure rollers 68 engage the upper surface of the work or spar and the spring-actuated pressure rollers lE9' engage one side of the spar operated upon which latter is indicated by the numeral 20,-Fig. `11. The spar: rests against a fixed flange l0. A former bar 'H as indicated in this figure may be employed to effect lateral shift of the horizontal cutting unit in horizontal slide-ways by engaging a roller lf2.

carried by the cutting unit and movementof. the cutter unit in a vertical plane is effected by roller 2| engaging former bar 4. Y r It has been mentioned that pneumatic means as illustrated in Fig. 7 is employed to change the drive ratio of the travelling carriage along the Work-supporting table. This is under the control of the operator through conveniently located valves, not illustrated. When the machine is em-` ployed for doing continuously repetitive.Y work,- cams 13, Fig. 2, are attached to a longitudinal flange at the bottom of the machine for the pur-` pose of automatically operating the ratio control valves. The speed of thetravelling carriage is always made to decrease upon the need forin-V crease in quantity of material removed at` any point along the working stroke ofthe carriage.

The machine is of that flexible nature that it maybe set to do the shaping work on most any-oi the main spars or beams employed atthepresent time in aeroplane construction. The operation of the machine is, therefore,ivariable and depending upon the shape of the formerbars 4 employed for any particular job. The working stroke ofthe carriage is to the left, Fig. l, and depend-ing upon thelength of thevtable, may be that required 'for shaping a single spar or a succession of differently shaped spars', strung along the length of the table. The material operated upon is quite resilient, that is, when a spar is lifted at one end, it assumes an arcuate form. The overhanging arrangement of the carriage, therefore, is convenient and a timesaver in that the spars may be loaded into the machine over one side of the table. Then, when thoroughly clamped in place as l previously described, shaping operations may be performed to assure the intended final form upon one operating stroke of the carriage. f

All cutting units may be lifted out of operative positions by the useof the pneumatic cylinders and latched clear of `the work. Since the lifting cylinders are double-acting, thecutting units are restored to operative positions in the same man-` ner. The limit of downward motion of each cutting unit `is controlled by former bars 4 which likewise serve to control lateral movementA of the cutting units. On special jobs where an inclined or warped surface cutis necessary, the oscillating capacity of the vertical cutters is employed to change the angular set of a cutteras illustrated by I claim: Y

1. A milling machine comprising a work-receiving table formed along one side thereof with a straight runway, a carriage tting said runway and overhanging the table, a plurality of cutting units movably supported by the carriage and each comprising a motor and a tool-carrying arbor, the mounting for one of said cutting units consisting of a pair of parallel arms each pivoted at one end to the carriage, a slide-way element pivotally connected with the opposite ends of said arms, a motor support mounting for rotation on said slideway element, and said motor support being formed with a slide-way for receiving the motor.

2. A milling machine comprisingAv a work-receiving table formed to make a straight runway for a cutting unit supporting carriage, a carriage resting on a runway ofthe tableland having mounted thereon a cutting `unit comprising a motor and driven tool; and a mounting for the cutting unit consisting of a pair of parallel arms, each pivoted at one end to the carriage, a link pivotally connected to the opposite ends of said arms, a motor support mounted for rotation on said link, and said motor support being formed with a slide-way for receiving the motor.

3. A milling machine, comprising a work-receiving table formed with a straight runway, a carriage tting said runway and overhanging the table, a cutting unit comprising a motor and driven tool, a mounting for the cutting unit comprising a pair of parallel arms, each pivoted at one end to the carriage, a link construction connecting the opposite ends of the arms, a support for said motor mounted for rotation and carried by said link construction, and means for changing angular setting of the motor during travel of the carriage along the table including a crank operatively connected with said arms for actuating the same, mechanism on the carriage for actuating the crank, and means on the table for controlling the crank actuating mechanism.

4. A milling machine comprising a work-receiving table, a carriage mounted for movement only along the table, driving mechanism for causing the carriage to travel along the work-receiving table, the driving mechanism including a speed varying means, cams on the table for regulating the speed of the carriage, a plurality of cutting units supported on the carriage and with mountings permitting the individual shifting of said cutting units relative to the longitudinal movement of the carriage, and a template bar mounted on the table in position to coact with said cutting units and regulate movement of the cutting units on the carriage, said cams being positioned with relation to the template bar for controlling the speed of the carriage to slow down and speed up the travel of the carriage according to the depth of the cut of ther cutting units.

5. A milling machine comprising a work support and a carriage mounted on said work support to travel thereon, a` drive mechanism for causing the carriage to travel along the work support, driven cutting units movably mounted on said carriage, a template bar secured to the work support in position for co-action with the cutting units to regulate movements of the cutting units on` the carriage, and traveling work-securing means connected to the carriage and provided with rollers guided on the work support for movement with the carriage relative to the Work support, said work-Securing means including pres.-

sure rollers for engagement with the material operated upon and supported by said'work support.

6. A milling. machine comprising a work-receiving table formed to make a straight runway for a cutting unit supporting carriage, a carriage resting on the runway of the table, parallel links extending from the carriage and pivoted at their inner ends to the same and forming a double arm linkage, a cutting unit supporting link pivotally connected to the outer ends of the parallel links and having a horizontal guideway, pivotally connected inner and outer pivot blocks, the inner pivot block being slidably mounted in said horizontal guideway and the outer pivot block having a vertical guideway, a cutting tool unit slideable in the vertical guideway of the outer pivot block and comprising a motor, a driven tool and a guide roller, a. crank mechanism connected with the parallel links for swinging the same to shift the cutting unit laterally, and means `on the table for engaging the guide roller for automatically changing the angular setting of the cutting unit during the travel of the carriage along the table.

7. A milling machine comprising a work-receiving table formed to make a straight runway for a cutting unit supporting carriage, a carriage resting on, the runway of the table, parallel links extending from the lcarriage and pivoted at their inner ends to the same and forming a double arm linkage, a cutting unit supporting link pivotally connected to the outer ends of the parallel links and having a horizontal guideway, pivotally connected inner and outer pivot blocks, the inner pivot block being slideably mounted in said horizontal guideway and the outer pivot block having a vertical guideway, a cutting tool unit slideable in the vertical guideway of the outer pivot block and comprising a motor, a driven tool and a guide roller, a crank mechanism connected with the parallel links for shifting the cutting unit laterally, and means for raising and lowering and for changing the angular setting of the cutting unit automatically during the travel of the carriage along the table.

A8. A milling machine comprising a work-receiving table formed to make a straight runway for a cutting unit supporting'carriage, a carriage resting on the runway of the table and having mounted thereon a cutting unit comprising a motor and driven tool, a mounting for the cutting unit comprising a pair of parallel arms, each pivoted at one end to the carriage, a link pivotally connected to the opposite ends or said arms, a motor support mounted for rotation on said link, crank mechanism connected with the parallel links for swinging the same to shift the cutting unit laterally, and a double acting air pressure cylinder having a piston connected with the crank mechanism for maintaining the cutting unit in cutting position and yieldable to prevent injury to the cutting unit.

9. A milling machine comprising a work support, a carriage mounted on said work support to travel thereon, a drive mechanism for causing the carriage to travel along the work support, driven cutting units mounted on said carriage and arranged to operate on material supported on the work support, and traveling work-securing means connected with the carriage and provided with rollers guided. on the work support for movement with the carriage relative to the work support, said work-securing means including pressure rollers for engagement with the material operated upon and supported by said work support.

10. A milling machine comprising a work-receiving table formed with a straight runway, a carriage tting said runway and overhanging the table, a cutting unit movably supported by the carriage and comprising a motor and a driven tool, the mounting for the cutting unit including a pair of parallel arms, each pivoted at one end to the carriage, a link pivotally connected with the opposite ends of said arms and a motor support mounted for rotation on said link, crank mechanism operatively connected with said arms for swinging the same, a guide roller carried by said link, and means mounted on the table and cooperating with the guide roller to effect lateral shifting of the cutting unit.

11. A milling machine comprising a work-receiving table formed with a straight runway, a carriage fitting said runway and overhanging the table, a cutting unit movably supported by the carriage and comprising a motor and a driven tool, the mounting for the cutting unit including a pair of parallel arms, each pivoted at one end to the carriage, a link pivotally connected with the opposite ends of said arms and a motor'support mounted for rotation on said link, crank mechanism operatively connected with said arms for swinging the same, a guide roller carried by said link, means mounted on the table and cooperating with the guide roller to eiect lateral shifting of the cutting unit, and a uid pressure cylinder having a piston operatively connected with the cutting unit and arranged to resist lateral shifting of the cutting unit by said roller.

12. A milling machine comprising a work-receiving table formed with a straight runway, a carriage tting said runway and overhanging the table, a cutting unit comprising a motor and a driven tool, a mounting for the cutting unit consisting of a pair of parallel arms, each pivoted at one end to the carriage, a link pivotally connected to the opposite ends of said arms, a motor support mounted on the link for pivotal movement on a horizontal axis, said motor being mounted for vertical sliding movement on said support, guide rollers connected respectively with the motor support and with the motor, and means on the table cooperating with said rollers for effecting lateral shifting movement and vertical sliding movement of the motor.

13. A milling machine comprising a work-receiving table formed with a straight runway, a carriage fitting said runway and overhanging the table, a cutting unit comprising a motor and a driven tool, a mounting for the cutting unit consisting of a pair of parallel arms, each pivoted at one end to the carriage, a link pivotally connected to the opposite ends of said arms, crank mechanism operatively connected with the par.- allel arms for swinging the same, means mounted on the carriage and cooperating with the crank mechanism for shifting the cutting unit laterally, andV means for effecting a permanent setting of the pivoted cutting unit for making a uniform angular cut.

RUDOLPH F. ONSRUD.

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