US2583521A - Tube trimming and piercing machine - Google Patents

Description

2 SHEETS-SHEET l w l ES Q 3 b3 hm WW a all! H. F. TEMPLE Jan. 22, 1952 TUBE TRIMMING AND PIERCING MACHINE Filed March 2, 1950 Jan. 22, 1952 H. F. TEMPLE TUBE TRIMMING AND PIERCING MACHINE 2 SHEETS--SHEET 2 Filed March 2, 1950 INVEN TOR. Harold F Kemp/e AT ORNEY Patented Jan. 22, 1952 TUBE TRIMMING AND PIERCING MACHINE Harold F. Temple, Elmont, N. Y., assignor to Victor Industries Corporation, Brooklyn, N. Y., a

corporation of New York Application March 2, 1950, Serial No. 147,189 20 Claims. (01. 164-11) This application is a continuation in part of my application for Can Trimming Machine and Method, Serial No. 585,169, now abandoned.

The invention relates to trimming machines for operating upon small diameter thin metal cans or tubes open at one end and closed at the other and relates particularly to the means for holding the cans in place during operation thereon and for dismounting them when finished, and for trimming, beading or otherwise shaping and piercing the cans at the same time.

In trimming machines of the type mentioned, there are customarily provided a rotatable arbor or mandrel on which the can is mounted loosely and an oscillatory tool holder having a revoluble shaft. Difficulty has been experienced not only in holdin the work on the mandrel in the exact position required for accurate operations thereon, but also in performing accurate trimming and other operations on the work such as to form an open end tube of an exact length within narrow limits such as is necessary for example in radio tube shield cans, condenser cans and the like. Difficulty has also been experienced in removing the scrap piece or waste material left from the trimming and piercing operations, which removal has often been necessarily done manually. Nor has been possible to pierce the end of the rotating can on the mandrel while the trimming or shaping operations are performed.

This invention therefore contemplates the provision of means acting on the closed end portion of a tubular work piece for holding and maintaining the work in an exact predetermined position on a mandrel, said means including fluid pressure applying means and mechanical pressureapplying means acting just before and while the work is engaged by the trimming and shaping tools, such engagement occurring at the same relative point of each piece mounted in the machine.

The invention further contemplates the provision of means for piercing the closed end of the rotating can while other operations such as trimming and beading, filleting or other shaping operations are performed on the lateral surface of the can.

The invention further contemplates the provision of simple, inexpensive but effective means for dismounting the can and any scrap material resulting from the operations, thereby attaining a finished can trimmed to length, beaded or filleted or otherwise shaped if desired, and also pierced if desired and dismounted in a single manual setup of the can on the same mandrel of the same machine.

The invention further contemplates the provision of revoluble means for adequately holding the closed end of the can concentric with the mandrel durin the trimming and other operations which temporarily spring or distort another part of the can into a position eccentric of the mandrel.

The various objects of the invention will be clear from the description which follows and from the drawings, in which Fig. 1 is a front elvational view of part of the machine showing the mandrel and the holding and piercing means for the work partly in section and in dotted lines in the retracted positions thereof, and also showing the trimmin tools in dotted lines in the retracted positions thereof.

Fig. 2 is a vertical sectional view of the mandrel and of the can as they appear while the work hangs freely on the mandrel out of engagement with the trimming and beading tools and the piercing punch.

Fig. 3 is a similar sectional view taken on the line 3--3 of Fig. 1, showing the can slightly and temporarily distorted by the revolving tools.

Fig. 4 is a similar sectional view of the mandrel and of the finished work, showing the approximate position assumed by the latter and the clearance between the mandrel and the work when the work is blown off the mandrel.

Fig. 5 is a top plan view, partly in section, of the means for actuating the moving parts and for timin the blasts, the frame of the machine being omitted.

Fig. 6 is a front elevational view of the same, partly in section.

Fig. '7 is a fragmentary front elevational view and vertical section of the work holding and piercing means in a modified form.

Fig. 8 is a side elevational view of the blowoff pipe surrounding the mandrel.

Figs. 9-12 are front elevational views of some of the various cans or tubes which can. be produced on the machine by the use of suitable revolving tools and, correspondingly shaped mandrels.

The typical machine to which the invention is applicable includes a revolving mandrel as l5 and an oscillatory and revoluble tool carrying arbor as I6 adapted to carry one or more revolving'tools toward and from the mandrel and to maintain the tools in contact with the work blank for one or more revolutions of the mandrel. By means of the present invention, it becomes possible to perform substantially simultaneously.

; a number of highly accurate operations in a single setup of the work on the mandrel and thereby to produce the required can accurately and in quantity on the same machine, and similarly to produce any one of a number of differently shaped cans merely by changing the tools or the work mounting and hOldil'lg devices, or

both. 7

.As best seen in Figs. and 6, the work or mandrel" arbor I5 is rotated by the shaft I? to which it is operatively connected in any well known manner, said shaft being rotated through i the gear l8 thereon which mesheswith the 'gear I9 on the driven shaft 20. A suitable motor as 2| drives said shaft throughthe motor pulley 22, the belt 23 and the pulley- 26 on the'shaft 20'? To supply a timed blast for automatically ejecting scrap resulting from theend piercing operation after the cycle of operations has been completed, the mandrel shaft IT has a longitudinalpass into the pipe 34 ontheothenside of the valve and thence to enter the opening '25 Thetool arbor 18 is designedto hold, rotate and oscillate towardand from the mandrel, any number of suitable circular tools such as the trimming: tool 35 (Figs. 1 and 7), the grooving tool 36- (Figs; 1- and '3 or thefilletformingtool 31- (Fig.- '7) with suitable spacers-as SBztherebetween. While the-tools for shaping the various forms of be'ads of ;the cans-39, Biiand All of Figs.

10; ll and 12 are not shown, such: tools are well understood and need not be describedindetail.

Themandrels |-5of --Fi g--.- 1 and-42=of Figefli are suitably shaped andi dimensioned to cooperate with the revolving tools 36; 31 or the likento shape or cut-that partof the can or tube pressed therebetween in a well known manner; For. example, in Fig.- 10 the shaping operation". is the formation of the-bead -43, which is mainly convex outwardly butwhich is bounded byoutwardly concaveedges. The mandrel in that case would have a bead" bounded by -similar concave edges andofthe same cross sectional size and shape as that of the inner surface of the bead-L IrrFig. 1'1, thebeadfla is bounded by only one concaveedge portion and in Fig. l2, the bead43b hasn0 con-. cave edges; Shapesother than beads may obviously be formed as may-be found-necessary, and the tools and mandrel in thatcase; arershaped accordingly.

To oscillateand'rotate the toolshaft-lt; an oscillatory bifurcatedframe isprovided, said-frame being pivotcd on thedriven shaft 20 (Figs '5 and 6')" and -having-one arm 44 supporting the shaft lteand another arm 45 supporting the auxiliary sprocket shaft 45. The shaft 29 carries the sprocket wheel-4l while theshafts I hand 46 .carry the respective sprocket wheels 48 and 49; Pass-:

ing aroundsaid wheels is thechain 53 whereby rotation of the shaft 20 r causes" rotation: of the shaft It; An adiustab1erod 5'l issecured atone end to the arm 45-ofthesprocket frame and at theother end is connected to-an endiof the crank lever:52 pivoted to the frame; of the machine as at 53z The otherend part-of the crank lever is connected to the bar 54-:havinga slot 55ntherein throughwhich:slotepasses the-cam shaft 29. Pro-.-v

jecting from the bar 54 is the pin 56 drawn into contact with the cam 51 on the shaft 29 by the tension spring 58. Said spring is connected at one end to the crank lever 52 and at the other end to the frame of the machine as at 59, whereby the spring, when permitted to do so by the cam 51, pullstheishaft lfiin ax counter clockwise direction as viewed in Fig: 6 and**away--from the mandrel l5. Said cam is properly shaped to move the pin 56 and..the bar 54 toward the left at the proper time-therebyto rotate the lever 52 in a clockwise direction, moving the rod 5! toward the right-andirotating the frame and the parts carried -thereby in a clockwise direction to move the tool shaft- 5- toward the mandrel.

To time the work blow-off blast through the V pipe 60, the cam" ti on the cam shaft 29 operates the spr-ing-closed valve 62 interposed between the pipe 60 and the air supply pipe 33. Said pipe 69 terminates at its; upper. end in a, loop;63 (Figs. 1, '7 andS) concentric-withandin slightly-spaced relation; to; and: around the mandrel shaft; H; The, loop isprovided with. a number of holes-54 unevenly spaced circumferentially aroundv the loop-and inclined tothe axis of -the mandrel and on the side ofzthe loop; nearer the revolving tools for the dischargeof-a,dismounting air blast along thermandrel l5 ori i2. The holesefitare prefen ably-concentrated more closely toward one side and nearthe bottom-,of-theloopas best seen in Fig .v 8, because-the scrapa-nd the released work tend tor hang on the mandrel tangent thereto at a pointof'fthevertical center line of the mandrel owing to the rotation of-,-the ;mandrel.in thedig rection of the arrow. of Fig. 8; Mostofthe holes- 64. are. therefore provided where. the. space 68 .between theworkandthemandrelis greatest and wherethe greatest amount of blast fluid istherefore required to perform thebloweoff operation. The blast emerges from the holes 84in the form of-a hollow cone as showngenerally by the. arrows of Figs. 1 and'l'hand applies dismounting pressure, in a direction. generally longitudinal of the mandrel as well asaround the outside of the man,- drel, and the inner and outer. surfaces of the scrap piece '65 ofjFig; 1 or fidof Fig. 'land on the finished'work 6120f Fig. 1 or 69, of Fig. '7.

The wor l tobe; trimmed and shaped is in the formof a tube blank as, 2, and is mounted on the, mandrel manually; To. permit" easy mounting and also to' permit easy dismounting of the;.fi ni'shed can or tube' after it has been bfeaded or grooved; the diameter of the mandrel ismadesufficiently lessthan the diameter of the inside Offthfij tube; as is' well understood in the art, or in other words the tube-is considerably larger'than the mandrel. Consequently, the tube blank merely hangs on the rotating mandrelin about the position shown in Fig; 2 before it-is pressed intotrimming and" shaping position by the means forholding the end portion of thetub'e or by the revolving; tools. However, means are provided" to assisttheoperator to mount the blank and to relieve theoperator ofth'enecessity formoving the blankall the :wayon to the mandrel: Itwill'be"understoodthat the l onger the operators hand remains in contactwith the blank, the greater the danger of injury to her by her failure-to withdraw her; hand in time, or the slowerthe speed-of the machine to give her sufiicient' time for that-purpose.-

Saidmountingmeans'takes the-form of a-properly: timed blast acting: on thelclosed bottom--16 ofi the'tube asit-is released bytheroperator, theblast passing; through". their reciprocating.v centering, holding and piercing mechanism 11 of Eig fl and 18 of Fig. 1 and through the piston rod or pipe 8| to complete the mounting of the tube after it has been partially mounted by the operator, thereby giving the operator sufficient time to withdraw herhand before the holding mechanism engages the end portion of the tube or the revolving tools engage the lateral surface of the tube. Exact synchronization of the operation of the tools becomes unimportant when the mounting blast is used, since said blast positions and holds the work properly against the end of the mandrel until either the tools or the holding means come into operation. The passages for the blast through the holding means will be later described in connection with the description of said means. The blast is operative when the tool shaft I6 is retracted from the mandrel as shown by the dotted lines of Fig. 1 and when the holding means is also retracted. The blast is timed to operate alternately with the dismounting blast through the holes 64 of the pipe 63. For this purpose, the cam I2 mounted on the cam shaft 29 operates the valve I3 which is interposed between the air supply pipe 33 and the pipe I4 leading to the pipe 8! through the flexible pipe I5.

The pipe 8I serves also as a piston rod, carrying at the end thereof the piston I9 reciprocating in the cylinder 82 and urged away from the mandrel by the spring 83. Air is supplied behind the pis ton at the proper time through the branch pipe 84 to force the piston, together with the pipe BI and the holding and piercing parts carried thereby, toward the mandrel against the action of the spring 83.

In the form of the holding and piercing means shown in Fig. l, the punch holder 94 is revolubly secured to the end part of the pipe 8| as by means of the set screw 80, the inner end of which is inserted into and runs in the groove 9|] around the pipe. A second pipe as I 8Iscrewed to the holder 94 as at I94 and arranged inside of the pipe 8| may serve if desired as an additional bearing for the latter. 'Io permit the blast to pass out of the pipes BI and I8I, a central hole 85 is provided in the punch holder and communicates with the radial holes 86 and 81 leading to the circumferentially spaced holes I81 through which the blast emerges from the holder. In the extension 88 of the holder is mounted the suitable punch 89 of such length that its operative end lies within the sleeve 9I at all times, the punch having the central blast passage I89 therethrough communicating with the hole 85. At one end thereof, the sleeve is removably secured to the holder 94 as by the screw threads I!!! whereby another similar sleeve may be substituted when the tube diameter is changed. At its free end, the sleeve is rounded, bevelled or flared properly to'guide'the end portion of the tube blank into engagement with the inner cylindrical surface of the sleeve and to center said end portion accurately and concentrically around the corresponding end of the mandrel I5, when the sleeve is 'moved to the position shown in Fig. 1 in which it embraces the tube end portion and the end sleeve around the punch through the holes I81 automatically completes the mounting of the blank III on the mandrel I5, the mounting having been initiated manually. At the same time, the pipe 8| together with the parts secured thereto move longitudinally toward the mandrel under the air pressure on the piston 19. The closed end part of the tube blank then enters the flared part of the, sleeve and is guided to a position concentric with the mandrel, while the end wall 16 of the blank engages the button and moves said button into the sleeve against the action of the spring 96, thereby pressing the end wall of the tube firmly against the end surface of the mandrel and holding the blank firmly on the mandrel. The air pressure on the piston and the blast may persist during operation of the tools on the shaft I6. However, as the blank moves into the sleeve to the position of Fig. 1, the punch 89 pierces the end wall of the blank in cooperation with the female die 91 of the mandrel, to punch out a small disc and to form the desired hole in the end of the blank. The tools 35 and 36 or 31 in the meantime have descended toward the rotating mandrel, the tool 35 to trim the blank to length, the tool 36 to indent or groove the blank or the tool 31 to form the corner fillet as I02, Fig. 7. The closed end part of the blank being held concentrically of the mandrel, it is obvious that the pressure of the rotating tools upon the blank: to close the space I68, Fig. 4, between the unstressed blank and the mandrel, distorts the blank momentarily as shown in Figs. Land 3 at the successive points where the tools apply such pressure. The distortion, however, is so slight and of such short duration that the tube, even though thin, springs back to its normal shape as soon as it is released by the tools. Pressure of the tools on the work causes the work to rotate, as does the pressure of the button 95 on the blank. Rotation of the mandrel is thereby imparted not only to the blank but also to the button, sleeve and punch, making it possible to pierce a rotating blank while or just prior to the trimming and shaping of the blank.

It has been hereinbefore explained that the mandrel is suitably shaped to cooperate with any selected revolving tools in the shaping and trimming of the tube blank. For example, the trimming tool 35 cooperates with the shoulder I35 of the mandrel to shear the blank to length. The groove I36 similarly cooperates with the grooving tool 36, but is so shaped and dimensioned as to avoid sticking of the work therein, thereby to per.-

. mit the tube to be readily blown off the mandrel.

Preferably therefore, the mandrel groove I36 is slightly deeper than the depth of the groove to be formed in the blank or the depth of the projecting part of the beading tool, so that the inside surface of the bottom wall of the groove in the blank is not quite in contact with the outer face of the annular groove in the mandrel. Similarly, the side walls of the beading tool converge somewhat inwardly, while the side Walls of the groove I36 are parallel and in planes perpendicular to the axis of the mandrel as shown in Fig. 1. When the work 61 is released by the tools and the sleeve 9I, the blast through the pipe 60 and the holes 64 thereof becomes effective to raise the work out of contact with the mandrel sufliciently for the blast to perform its .dismounting function, the inner diameter of the groove in the work being slightly greater than the outer diameter of the mandrel as shown by the space I68 therebetween in Fig. 4. It will be understood that the air blast through the punch hole t8?! and through the-hole [81 of the punchholder'iscut 0'iT"'du-ring the-retraction of the sieeveso as'n'ot" to interfere with thedis mounting operation; which dis'mounts the scrap piece-as well a's the work:

ln-that formpf' the mandrel and of the support means for the closed"- end ofthatuheshownih Fig: '7; the punch (1 6 projects axially" from the. fi ee end of the mandrel 42- and cooperates-with the button I H topierce andto punch outa disc from the endof thetube'; the'punch-enteringj the n w 1 :32 inthe button: The blast' through the pipes 8 Pandl 8' serves-'to ejectthe'scrap'or punch: ingzdepositedin the-hole- I l-2 6y- "the -punch. The remaining parts" of the holder Ti f being similar to' thosepfthe holderlfi: no further description thereof appears necessary: In thisform*of' the invention, themounting blast' through the pipes allthe way on 'themandrel because of' thednter' ferenee of the punch H 0i However; the work" holder F5 "is effective to complete the-mounting of the'b'lank, to arrange the end of-the blanhin prop er-concentric relation tothe endpart of the'man drel= and to punch" the hole in theend wall of the blankj ust before the revolving; tools engage the blank: The button-= H F presses-the end-wall off the "blank" against" thefre'e 'end of the-mandrel 4'2"-during'the"shaping operations-on the blank;

b'ut' such shapingpperations follow" the-punching operatibn-on th-e -rotatingcworkso closely that" the punching and shaping operations may; be said*to take placesubstantiallysimultaneously: The pressure"- of the Work holder" on the end. of" the blank "causes' the button-"to mutate and also cause different 'sizesandshapespeculiarly designed-for s the formation of the -particularfinished 'tuber As shown in Fig: 1*,themandrel leis-hollow and is screwed on" totheman'drel' shaft .l 'Fby' the waist in'g screw threads! I51" A" female 'die 9T Xe'diin the end part of the mandrel cooperates' with. the punch 89" to ClJtTthE' small disci as 1'91 out ofgthe end Wall" 16 of the blank thereby to produce the hole 116. Suitable radialholesllllinthe'mandrel receive the wa'stepunchings and .permitthemto drop-out of the mandrel whenthe scrap piece 65" andt'he'work are blown offthe mandrel; should the punchings- I 91" fail to" drop out of the holes Ill-l; theblastthroughthe'opening Z B effects the ej ection thereof;

It" will now be understood that the present in-. vention providesmeans effective" to" complete the mounting of'a tubulanblankonasmallertm'andrel afterthe mounting operation has'been' manually initiated, then to trim; shape and pierce. the blank substantially simultaneously whilethebla'nk r0; tates; the piereing being accomplishedb'y a'punch which is revolubly mounted, thatlthe closed end of the blank iscenter'ed concentrically of 1 the mandrel duringitheeperations on the blankgwhile' the other'part of the blank is pressed against the mandrer and -is consequent1y-*- arranged tempo rarily eccentrically with respect'thereto; that' sim' pie but adequate fluid pressure= applyihg means have-been provided todi'sinount the'finished'worl as W811 as the'scrapresulting from the-operatiens; and thattl'ie'struct'ure' provided is well designed to meet all practicalrequirementsz- While certain specific formsof theaihvention have herein been shown anddescribed; various changeemay obviouslvbe "made-therein without" departing" from tlie spirif 0f' the-*inVentib1T- d finecl'in'theappended claimsi 12' In a tube trimming machine; a revoluhle mandrel constituting a' first" support means *fbna generally" cylindrical tube havingpne'closed en'd and'the otherend open; the tube no'rma lly hang ing': eccentrically on the mandrel, arevoluble tool; means formoving thetooltoward and from the" mandrel" t6 press "the tube between the tool and the mandrel}, and means for holding? the closed? end portion of the tuhe' 'concentrically withthemandrelduring the operation'of the; tool on thetube thereby temporarilyto" distort the tubeysaid holding: means comp'risin'gta ,sIeeve'a-r ranged" in axial alignmentwith the mandrel, means to reciprocate the sleeve longitudinally t'owardand' from the mandrel; theinner-di'anreter of the sleeve being Y greater" than the": outer diameter-0f the mandr'el; .$aid-sleeveireceivinggthe mandrel and" the closed end 1 portion of" thet'ube therein when the sleeve is nearest the mandreli a" springpressed rotatable button constituting a second support means, for thetube and mounted f0r"10ngitudiha1slidirig movement in" the sleeve intoa position in pressed contact With'the closed endiof thetube to'press said endagainst theehd of the mandrel and'fa;'revoluble-"mountmg for-the button and sleeve. 7

2. The" machineof" claim 1'; anpiercing" punch carried by one'of the-support: meansand. rotat= able therewith; the" other" of the? support means having a .centralholejtherein torreceivethe punch on the"reciprocation of 'theisleeve: v

3": The" machine of"claim* I; the buttbnzhaving a central" hole therein,. and" a punch projecting from-thetmandrel and'arrangedtdenter' theihole inithe button on the' reciproeationiof;the: sleeve.

4; The machine oficlaim 1;. the pressure of", the button against 'theLtube' aiding to rotate; the tube, the mandrel and" the, button each having, an axially, arranged. hole therein, a punchccarriedlby and rotatable withthe sleeve andi in axiallali'gn; ment with the hole. in .the..button,.,the punchten tering the hole in thecmandrel,onltheireeiproca tion of the sleeve therebytopiercewthe endliof the rotating'ftuber 5. The machine of claim. 1, the tool being a trimming, tool, the mandrel having a; trimmin shoulder, thereon cooperating with. the: tool v to trim a cylindrical. tubular scrap piece from. the open; end; part of l the. tube a. pipe loop; around theinner endpart ofllthe. mandrel, saidloophavring' a plurality or Icircumferentially spacedublast discharge" holesvin the side wal lvthereofg the axes of the holes: being inclined. to the. axis: bf;v the mandrel, andz'me'ans for deliveringiatblast through theloop toblow thee-scrap piece .andI.thestubeofi the. mandrel onthe retraction of the sleeveand the to'oLaWayi-fromthe' mandrel; I

6? The machine of claim-1; 1,,thetook-beingv a trimming tool the. mandrel! having a trimming shoulder thereon cooperatingwith the toolltoitrim a tubular-scrap. piece from the" tube,-, and. ahpipe loop around the mandrel and having circumferentially spaced apart blast discharge openings therein shaped to deliver a hollow conical blast circumferentially upon the scrap piece and the tube to dismount said piece and tube from the mandrel.

'7. In a tube trimming machine, a mandrel, means to rotate the mandrel, a trimming tool, means to swing the tool toward and from the mandrel, means to rotate the tool to trim off a scrap piece from the tube, tube-holding means to receive, embrace and support the end part of a tube carried by and of greater diameter than the diameter of the mandrel, said means holding the end part of the tube concentrically of the mandrel while the tool presses another part of the tube temporarily against the mandrel and thereby arranges said another part of the tube eccentrically f the mandrel and rotates the tube, means to reciprocate the tube-holding means toward and from the mandrel, and means surrounding the mandrel to deliver a hollow conical blast around the mandrel and thereby to dismount the scrap piece and the tube.

8. The machine of claim 7, and means associated with the tube-holdin means to punch a central hole in the end wall of the tube while the tube is held by the tube-holding means.

9. The machine of claim 8, the tube-holding means including a sleeve and a spring-pressed perforated button slidably axially in the sleeve.

10. The machine of claim 7, and means for delivering a blast through the tube-holding means to assist in mounting a partly mounted tube on the mandrel.

11. The machine of claim 10, and means associated with the tube-holding means to pierce the end wall of the tube.

12. The machine of claim 7, the mandrel having a longitudinal hole therein communicating with a transverse hole therethrough and a punch carried by and rotatable with the tube-holding means and depositing a punching from the tube into the longitudinal hole in the mandrel.

13. The machine of claim 12 and means for delivering a blast through the tube-holding means and the punch when the dismounting blast is inoperative.

14. In a tube trimming machine, a revoluble mandrel to enter and to rotate a tube, means to rotate the mandrel, a die having a hole therer.

through and carried by the mandrel for rotation therewith, a sleeve reciprocating toward and from the mandrel and receiving therein the end portion of the mandrel and the closed end portion of a tube mounted on the mandrel when the sleeve is nearest the mandrel, means reciprocating the sleeve toward and from the mandrel, a perforated member slidable and rotatably mounted within the sleeve and arranged to engage the closed end portion of the tube and to rotate therewith, a spring within the sleeve urging the member out of the sleeve, coacting stop shoulders on the sleeve and member to limit the outward movement of the member, a piercing punch in the sleeve adapted to pass through the member and into the hole of the die when said closed portion and said member slide into the sleeve, and a revoluble mounting for the sleeve and the punch.

15. The machine of claim 14 and means for directing a blast through the sleeve and the member toward the mandrel.

16. The machine of claim 14, the sleeve bein in coaxial alignment with the mandrel and of greater inner diameter than the outer diameter of the mandrel and thereby holding the end portoward and from the mandrel, means to-rotate the tool, a trimming shoulder on the mandrel coplanar with the tool and cooperating therewith to trim the other end portion of the tube and to press upon that part of the tube being trimmed to hold said part against the mandrel temporarily and in eccentric relation to the mandrel.

17. In a tube trimming machine, a revoluble mandrel having a trimming shoulder thereon and adapted to support a tube having a closed 'endand an open end, means to rotate the mandrel, a pipe arranged in longitudinal spaced relation to the mandrel and in axial alignment therewith, means for directing a blast through the pipe toward the mandrel and upon the closed end of a tube partly mounted on the mandrel to complete the mounting of the tube, revoluble means cooperating with the shoulder to trim a ring of scrap off the open end of the tube and to leave the scrap ring on the mandrel, means to move the revoluble means toward and from the mandrel, means to rotate the revoluble means, a second pipe in the form of a ring around the inner end portion of the mandrel, the pipe ring having perforations in the wall thereof and being closed at the end thereof whereby a blast into the ring emerges through the perforations in annular form around the mandrel and moves longitudinally around the outside of the mandrel and against the surfaces of the scrap'r-ing and the tube to blow said scrap ring and tube oil the mandrel.

18. In a tube trimming machine, a revoluble trimming tool, a cylindrical mandrel adapted to enter a tube and having a part cooperating with the tool to trim one end of a tube, the mandrel having a longitudinal opening therethrough and a transverse opening communicating with the longitudinal opening, means for oscillating the tool toward and from the mandrel, means in longitudinal spaced relation to the mandrel for directing an air blast in one direction toward the mandrel, means for directing a second air blast in the opposite direction to encompass the outside of the mandrel and also to pass through said openings, a pointed reciprocating piercing punch arranged coaxially of the mandrel and cooperating therewith to pierce the closed end of a tube during the rotation of the tube by the mandrel and to deposit the scrap produced by the punch in said longitudinal opening, yieldable means adjacent the punch to exert pressure on said closed end during the operation of said tool and punch, a housing for the punch and for said yieldable means confining said first-mentioned air blast to said one direction, and means for reciprocating the housing toward and from the mandrel.

19. In a tube trimming machine, a revoluble mandrel having a longitudinal opening therethrough and a transverse opening communicating with the longitudinal opening, punch-holding means reciprocating toward and from the mandrel for completing themounting of a cylindrical tube having a closed end on the mandrel and for holding the tube on and causing the tube to rotate with the mandrel, said means comprising a sleeve, a spring-pressed member having a longitudinal hole therethrough slidable in the sleeve and adapted to press upon the end of the tube and a piercing punch rotatably mounted within the sleeve, a die adjacent the transverse opening 11 within .the mandrel and .coo.perating with .the gpunch to tpierce the :end of the -tube, 1 means for 'rdirecting a blast through :the .esleeve land vsaid ixmember .toward thermandrehmeans IonreciproeatingTthe punch-holdingemeans and the punch :teward and from-themandrel, a revolublemount- J g for the punch, sleeve and member, and means r-rdl-recting a' second blast through Ether-mandrel to eeiect the punching lproduced hy the ,punch through the transverse opening.

20...-'In a tube trimming machine, a .revoluble :mandrel: adapted tor-have1a tubev-havingc-a closed z-flat end mounte.d thereon and .rotated thereby, ..tne .mandrel having ca part .r-thereof reduced .-in .cdiameter-to receive: the trimmingtool hereinafter .mentioned, -a :sleeve c-reciprocatory toward and zlfromethe. mandrel, a spring-pressed memberrsslidflame-within:thesleeve andrhavingva central open- ?ing :therein, tsaid amember gpressing upon "and irotating with the closed endof thel tube apunch a crotatably mounted mithincthesleeverand adapted coacting with the punch, a trimming tool ,coact- ,ing with andzoscillatory toward and from the vmandrel to-operate :upon the tube. substantially .simu1taneo.us1y withsthe operation-of therpunch and meansctocoscillate thertool toward andirom ,theemandrel.

c HAROLD v12'. IEMBLE.

"REFERENCES "CITED The following references are ofltrecord win :the file 'Offithis patent:

*UNITED STATES PATENTS

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