Page 1 of 8
`
`EDWARDS LIFESCIENCES EX. 1020
`Edwards Lifesciences v. Boston Scientific Scimed
`U.S. Patent No. 6,915,560
`
`

`
`Feb- 27. 1953»
`
`.1. w. SCHUEZTZ
`APPARATUS AND METHOD FOR POINTING TUBES
`
`3,370,451
`
`Filed June 28, 1965
`
`4 Sheets—Sheet 2
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`JAMES W. SCHUETZ
`
`""’5’;.'2%“,,,*'.:;‘,.:f/W"”°;¢..,;,a:
`
`ATTORNEYS.
`
`Page 2 of 8
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`Page 2 of 8
`
`

`
`F¢b- 27. 1953
`
`»
`
`J. w. SCHUETZ
`
`3,37b,451
`
`APPARATUS AND METHOD FOR POINTING TUBES
`
`Filed June 28, 1965
`
`4 ghee-ts_sheet 5
`
`77
`79 ‘(—r'4—’I4-?1—>1-»
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`
`
`
`30
`
`INVENTOR.
`
`JAMES W. SCHUETZ
`
`ATTORNEYS.
`
`Page 3 of 8
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`Page 3 of 8
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`

`
`F954 27: 1963 '
`
`J. w. SCHUETZ
`APPARATUS AND METHOD FOR POINTING TUBES
`
`3,370,451
`
`Filed June 28, 1965
`
`‘
`
`4 Sheets—Sheet 4
`
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`7
`INVENTOR.
`
`JAMES W. SCHUETZ
`
`BY ,
`
`AT TORN EYS.
`
`Page 4 of 8
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`Page 4 of 8
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`

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`_
`
`3,373,451
`'
`Pam, Fee 2.,’ 19,8
`United States Patent Office
`2
`1
`Briefly, a preferred form of apparatus comprises a fluid
`operated chuck or similar mechanism that is adapted to
`35703451
`urge a series of V-shaped gripper jaws or dies radially
`APPARATUS AND NIETHOD Fak
`inwardly into engagement with the length of tube to be
`James W. Seh1ietzPIh:ii?slb11;gllEPa., assignor to1§1aw_Kn0X
`.
`.
`.
`TI
`TUBES
`pointed. The jaws each have a series of longitudinally
`Coinpaiiy,Pittshiirgh,Pa., acorporation of Delaware
`spaced points that first engage the tube and thus hold the
`Filed June 28, 1965, Ser. No. 467,235
`tube against slippage with respect to the dies. As the jaws
`8 Claims. (Cl. 72-402)
`move inwardly,
`they fold the tube into a fluted form
`having a maximum dimension sufficiently smaller than
`in the original outer diameter of the tube to permit the end
`ABSTRACT OF THE DESCLOSURE
`of the tube readily to be inserted into the drawing die.
`The folding operation is completed in one continuous
`Apparatus for pointing metal ‘nibes preparatory to draw-
`movemeht or the laws arid 33 soon as the mward moVe'
`ly spaced apart about a central axis and adapted to fold
`ing them through a die embodying jaw members angular-
`merit of the jaws is completed,
`they are automatically
`*
`‘
`end of reduced diameter made in, of longitudinally ex_ 15 retracted so that the tube can be removed from the ap~
`the walls of a tube inwardly to produce a tube having an
`tending ribs separated by intervening flutes. The jaws are
`Parathe ready for drawing through 3 die-
`V-shaped and have sharp, longitudinally spaced projec-
`A3 Show“ m FIGURES 1 arid
`or the drhwmges 3 Pre'
`tions that first come into engagement with the wall of the
`rerred form or apparatus Comprises 3 eyhhder 10 5‘-113‘
`tube and hold the tube properly centered during the point.-
`Ported oh oh aPProPrmte base made up or 51 horizohlal
`ing Operation which takes place in one continuous inward 20 plate 11 and vertical plates 12 disposed at either end of
`Stroke ofthe jaws
`the cylinder 10 and having arcuate saddle portions to re-
`ceive the cylinder. The vertical members 12 preferably
` — are welded to the base member 11 and the cylinder 10
`may be welded to the vertical members 12. The internal
`bore of the cylinder 10 has a rear portion 14 of greatest
`This invention relates to an apparatus and method for
`diameter, an intermediate portion 15 of reduced diameter
`pointing tubes so that they may be inserted into dies for ‘:15
`and a forward end portion 16 of enlarged diameter as
`drawing the tubes to reduce their diameter.
`compared to the intermediate portion 15. At the front end
`It is necessary to provide what is known as a point on
`of the cylinder there is a front cylinder head 18 that is
`the end of a tube before it can be drawn through a die
`held in place by a key 19 and an annular ring 20 and
`to reduce its diameter; the point must have an overall
`is prevented from inward movement by a shoulder 21
`transverse dimension such that it readily can be inserted 39
`in the cylinder bore. There is also a rear cylinder head 22
`through the die and must be long enough so that the pro-
`that is held in place against a shoulder 23 in the cylinder
`jecting end of the point can be grasped by gripper tongs
`bore by a key 24 and a ring 25. The rear cylinder head
`or jaws or the like on the other side of the die. If the draw-
`is sealed to the cylinder as by a conventional O-ring 26.
`ing operation is to be carried out satisfactorily, the point
`In order to form the required points on tubes,
`at plu-
`and the juncture between the point and the remainder
`_
`_
`_
`of the tube must be nearly as strong as the tube itself
`_
`so that the metal will not be pulled apart during the
`rahty or ahghlarly Shdeed gr1PPer Jaws 30 are disposed
`drawing operation, and the point should be accurately
`Wrthm the eYhhder- _SiX laws are Shown in the didwihgss
`centered with respect to the tube to prevent distortion
`hut rewer or more laws ooh be employed i_r deS1Ted~ A
`of the tube during drawing. Also, the pointing operation ‘to time T 15 Shown ih FIGURES 1_ and 2 to illustrate the
`shenld he accomplished quickly and without requiring
`initial engagement between ‘the jaws and the tubes. In
`skill on the part of the operator and the apparatus for
`order to move the jaws 3!) inwardly to deform the tube
`carrying out the pointing operation should he stnidv, sini_
`to provide the desired flutes and reduce the diameter
`ple and capable of being rnanufactured at reasonable
`thereof: 3 hydraulically Operated Chuck 31 is disposed
`Cost
`45 within the cylinder 10. Chuck 31 is provided with radial
`A general object of the present invention is to provide
`elots 32 in which the laws _3-‘ti are Slidahly ihouilied and
`a machine and method for pointing tubes that meets the
`m ‘order to move the laws inwardly add 0‘—iiWa1"dlY “P011
`foregoing requirements. Other objects and advantages of
`axial moVemeht of the chuck: the_SloiS 33 are T-Shaped
`the invention will become apparent from the following
`35 5hoW_h: With enlarged head Opehihgs 33 that are defined
`description of a preferred form thereof, reference being 50 hy Slolilhg Outer Cammlhg S11TiaC‘3S 34 and ihuel‘ Cumming
`nindeto the aceninnanving drawings in which;
`surfaces 35 that are parallel to the surfaces 34. The jaws
`FIGURE 1 is a Vertical axial section illustrating a pre-
`30 are Pr0V1ded Wlih T heads 36, preferably composeé
`ferred form of apparatus embodyingthe presentinvention.
`or it material Such 33 hiohle in order to reduce friction
`l:lGUl;_E 2 is a transverse section taken along line
`the strips being secured to the jaws by cap screws 37. The
`2__2 ofNGURE l_
`55 forward ends of the jaws are provided with wear plate
`FIGURES 3 and 4 are side elevation and end views,
`38 _that bear againsttthe inner surface of the forwarc
`respectively, of a typical tube that has been pointed in
`CYl1_Y1<l€F head 18 Whlle the rear ends Of the laws hea
`the illustrated apparatus.
`against a washer 40 that is supported by a plug 41 the
`FIGURES 5 and 5 are side and end eievations, res,‘-,ec_
`projects inwardly from the rear cylinder head 22. Th
`tively, of one of the gripper jaws used to defgrm the tube" 60 Jaws aretprevented from longitudinal movement by th
`l:lGURE 7 illnstiates the inner or working face of
`front_cylinder head 18 and the washer 40 and thus recij
`the snippet. iaw illustrated in FIGURES 5 and 5_
`rocating movement of the chuck 31 within the cylinde
`l:lGURE 3 is a fraginentarv elevation showing the
`10 will cause the dies to move radially inwardly and on
`initial engagement between the gripper jaws and a tube
`wardly. The jaws and the chuck are shown in full linx
`55 in FIGURE 1 in their fully retracted position; the broke
`FElGURE 9 is a section taken as indicated by line 9-9
`hues 1h the l0WeT Part Of FIGURE 1 Indicate the lime
`tob pointed.
`,
`_
`_
`of }:lGURE 3.
`most position of the jaws and the corresponding forwa
`FIGURE 10 is a similar section, but showing the jaws
`Position of the Chuck-
`in iheil-innel-m0S1_-posifiol-l_
`In order to reciprocate the chuck 31 within the cylind
`FIGURE 11 is similar to FIGURE 10, but shows a 70 19, the chuck is provided With a rear piston portion I
`smaller tube, the tube being of the size shown in FIG-
`that Opefaies Within the hole 14 and also Slides 310
`URES 3 and 4_
`the plug 41, the piston portion 45 being sealed to t
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`Page 5 of 8
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`3
`cylindrical surface 14 and the outer surface of plug 41
`by appropriate packings such as the O—rings 46 and 47,
`respectively The chuck is also provided with a forward
`piston portion 49 that fits within the intermediate bore
`15 -of the cylinder, the required seal being provided by a
`packing such as the O-ring 50. With this arrangement,
`admission of fluid under pressure to the space 52 in back
`of the piston 45 will urge the chuck in the forward direc—
`tion toward the front cylinder head 18 and cam the jaws
`since the area of piston 45 is greater than the area of‘
`, 10
`piston 49, admission of fluid to the space, 53 -between
`the two piston portions of the chuck will cause the chuck
`
`5
`
`4
`is formed by folding the wall of the tube inwardly upon
`itself to provide flutes 71 It will be noted that the ribs
`72, which define the flutes or recesses, extend substantially
`radially and are substantially equally anoularly spaced
`and that the wall of the tube at the outer edge of each
`rib is bent through a sufficient angle that adjacent por-
`tions of the tube‘ Wall substantially Contact each’ other as
`shown at 73. The inward folding of the tube wall does not
`substantially elongate the tube in the axial directions, and
`substantially the same as the cross-sectional area of the
`therefore the cross-sectional ‘area throughout the point is
`original
`tube and has nearly the
`The point merges into the original
`
`gripper laws 30-
`connected to a source of fluid under pressure through
`Iaw members 30 of a
`appropriate controls which can take any convenient form.
`Preferably, the controls are arranged» so that the operator 20 dllee Pelnts shell 33 Sh0W11 in FIGURES 3
`only -has to push a button whereupontfluid under pressure
`trated in FIGURES l and 2, and
`will be admitted to the space 52 while flow of fluid from
`FIGURES 5. 5 and 7- Each law memh
`chuck in the forward direction and urging the Jaws in-
`that are adapted to slide in the radial slots 32 of the
`wardly to point the tube. Preferably, the control is such 25 Chuck lhe Outer surfaces Ofthe hotly P0rt10ns are slanted
`that fluid under pressure is applied to the space 52 until
`as shown to support the T heads 36 The mner portions
`the back pressure builds up to a predetermined degree,
`of the jaws extend parallel to the common axis of the
`whereupon the connections ale reversed to supply fluid
`eh’l-leki the eyllnller 19 and the tube t0 he Potnted The
`un er pressure to the space 53 through the conduit 56
`inner P0ttlhnS 0t the Jews are lorlned lnt0 V‘shaPe as
`and permit fluid to be discharaed fpom the space 52 to 30 s own at 80 with the Vs pointing radially inwardly to-
`t e sump This operation continues until a predetermined
`Ward the C0¢n1rn0n axis and their aPeXes Parallel t0 the
`back pressure is built up in the conduits leading to the
`common axis. The included angle of the V’s is preferably
`space 53, whereupon the pressure is shut ofl” and the
`equal to the anoular spacing between the radial slots 32
`apparatus is then in .condition for -another operation.
`ln the Chuck and lhetween the JEIWS 30 When they are In
`Controls capable of performing this type of sequence of 35 position within the chuck. Thus in the example given
`operations are well known to those skilled in the art and
`the angular spacing between the law members 1s 60
`arenot describedherein.
`—
`degrees and the included angle of the V—shaped portion
`order to limit the retractino stroke of the chuck and
`0f each Of the law Inetnhers ls Pretera’hlY also 50 degrees-
`thus to limit the outward movement ofthejaws to a posi-
`With this arrangement eaeh side 31 Of3 V-shaPedP0rt10I1
`tion in which their inner edges define a circle havlrl
`40 hes parallel to a slde 81 of an adlaeent jaw member The
`approximately the external diameter of the tube to be
`13W members: When rn0Ve<‘l 1nW3rfllY'h3’ the Chuck fold
`pointed, an adjustable stop is provided on the rear end
`the Wall Of the tube into the form shown each rib 72
`of the chuck 31. This comprises a guide bar 60 that is
`eing made up of two thicknesses of tube wall folded
`pressed into an opening in the rear of the piston portion
`substantially into contact with each other as shown at 73
`45 of the chuclcand extends rearwardly into a- bore 61
`In Order t0 l_3r0Vlde Clearance for the Walls Of light
`64 in a hollow boss 63 secured to the rear cylinder head
`P01ntS 30 Of the Jaws are relieved adjacent the apexes of
`g
`latively small diameter tubes, the V-shaped
`22.,The inner end of the adjustment shaft 62 has a flange»
`the V5 as sh0Wn at 32- The 'relleVed P0rtl0nS make It
`66 that eiieaoes the rear surface 67 of piston portion 45
`P0sSlhle t0 use the Same '
`
`sealed against leakage where it passes through the cyhh-
`.
`derhead 22 by an O-ring 69. Withthis arrangement rear-
`ward movement of the chuck is stopped by engagement
`of the chuck with the end flange 66;’ the position of the
`llange can be adjusted by the hand wheel 68. Theposition
`at maximum retraction of the jaws is shown in FIGURE
`I The gripper j'a-ws 30 are designed so as to accurately
`ohm strong pointed portions of the type Shown in FIG_
`JRES 3 and 4 on the ends of tubes of a Wide range of
`izes without requiring any chance in the gripper jaws
`
`:he chuck and the cylinder 10.
`
`tubes with a range ofoutsidediameters from 1.750inchto
`nt a single machine can form points on
`0625 inc , Without requiring adjustment except of the
`5 retraeted P0s1Ll0n Gt thelaws hY the hand Wheel 68
`As noted above the tubes to be pointed are first en-
`gaged hY’the PrOleetlohs 77 Of the laWs- These are l0ngl-
`tlldlnally spaced along the apaxes of the V’s and are
`V‘3haPed Phlhts t0rI_ne<l_ hY the inters
`surface 82. The projections preferably are slightly elon-
`gated in the direction parallel to the axis of the tube and
`Present Shall? edges 34 t0 a
`'
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`Page 6 of 8;
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`Page 6 of 8
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`

`
`3,370,451
`
`5
`the chuck. The tube is inserted into the chuck until the
`end of the tube engages the washer 40. Then, as previous-
`ly described, the chuck is actuated to move the jaw mem-
`bers radially inwardly.
`Inasmuch as the first engagement between the jaw mem-
`bers and the tube is with the points 77, the sharp edges
`84 of the points first indent the tube and thus prevent
`slippage of the tube with respect to the jaw members. Con-
`tinued inward movement of the jaw members then simply
`folds adjacent portions of the tube wall toward each other
`until, as shown in FIGURE 10, these wall portions are
`substantially in engagement with each other. When this
`position is reached, no further inward movement of the
`jaw members can take place by merely bending the metal;
`the metal would have to be compressed to permit the sur-
`faces 81 of adjacent jaw members to come closer together
`and to permit the jaw members to move nearer to the cen-
`ter line of the chuck. The pressure in the cylinder in back
`of the piston portion 45 of the chuck therefore increases
`and, as previously described, the chuck is returned to its
`initial position with the rear surface 67 of the chuck in
`engagement with the flange 66 of the adjusting shaft. This
`occurs when the parts have reached the position shown in
`FIGURE 10.
`It will be noted that the sharp points 77 of the jaws
`somewhat penetrate the bottoms of the flutes thereby pro-
`ducing the indentations indicated at 76 in FIGURE 3.
`Also, the outwardly flared portions 75 of the jaws produce
`the merging areas 74 between the point and the body of
`the tube. The bottoms of the fluted portions between the
`indentations 76 are rather flat as shown at 86, having
`been formed by the flat intermediate areas 83 of the jaws.
`The point is accurately centered with respect to the tube
`and accurately formed because the initial adjustment of
`the retracted position of the jaws insures that the tube
`will be properly centered with respect to the jaws when
`the operation is commenced and because the sharp points
`on the jaws substantially eliminate the possibility of slip-
`page between the metal of the tube wall and the jaws. The
`chuck moves the jaws inwardly uniformly and thus pro-
`vides the required accurate point in a single operation.
`After the jaws have been automatically retracted by the
`chuck, the operator only has to remove the pointed tube
`from the chuck and insert it through the drawing die in the
`usual manner.
`FIGURE 11 illustrates -the conclusion of a pointing op-
`eration as applied to a tube of smaller diameter and
`thinner wall. In carrying out
`this operation,
`the hand
`wheel is operated to screw the adjusting shaft inwardly
`and thus limit retracting movement of the jaws to the
`smaller outer diameter of the tube. The folding opera-
`tion occurs as before. However, it will be noted that the
`ribs 87 of this smaller lighter gauge tube are disposed
`within the relieved portions 82 of the jaws. If the jaws
`were not relieved, it would not be possible to point tubes
`of such small diameter using the same machine and the
`same jaws that are capable of pointing tubes of larger
`diameter and heavier wall. As noted above, a present
`type of machine is capable of pointing tubes having a
`wide range of outside diameters and of wall thicknesses.
`With tubes of thinner wall thickness, the points 77 fre-
`quently penetrate through the tube wall at the face of the
`indentations 76. This insures accurate holding of the tubes
`and centering of the tubes with respect to the chuck and
`the jaws and any weakening of the point that this action
`creates is inconsequential.
`From the foregoing, it will be evident that the inven-
`tion provides a method and apparatus whereby tubes of
`a wide range of sizes and wall thicknesses can be rapidly
`and accurately pointed by a single operation in a simple,
`sturdy and relatively inexpensive machine. The points are
`accurately centered with respect to the tube, the reduc-
`tion in dimension is adequate for ordinary drawing opera-
`tions and the strength of the points and the connection
`between the points and the tube is adequately maintained
`
`Or
`
`10
`
`[0 Dr
`
`40
`
`45
`
`50
`
`55
`
`60
`
`65
`
`70
`
`75
`
`6
`so that the tension exerted on the points during the draw-
`ing operation can be sustained without breakage.
`The essential characteristics of the invention are set
`forth in the appended claims.
`'
`I claim:
`1. Apparatus for pointing metal tubes preparatory to
`drawing them through a die, comprising a plurality of
`jaw members angularly spaced about a central axis; means
`for moving all of the jaw members simultaneously and
`at the same speed in radial directions toward said axis
`and for retracting said jaw members away from said axis
`to a definite position at which the jaw members are sub-
`stantially radially equidistant from said axis, each of
`said jaw members having an inner V-shaped portion pro-
`vided by plane surfaces extending parallel
`to said axis
`and adapted to engage the wall of a tube to be pointed,
`the V-shaped portions pointing radially inwardly toward
`said axis,
`the apexes of the V-shaped portions of said
`members each having a plurality of longitudinally spaced,
`sharp,
`tube-engaging projections and the jaw members
`having tube-wall engaging surfaces between the projec-
`tions,
`the projections being axially short as compared
`to the length of the surfaces between the projections.
`2. Apparatus according to claim 1 wherein the projec-
`tions have sharp,
`tube-engaging edges formed by the
`intersection of the plane surfaces of the jaw members.
`3. Apparatus according to claim 2 wherein the surface
`of the V-shaped jaw members is relieved adjacent the
`apexes of the V3 to provide clearance for the material
`of the wall of a tube being pointed.
`4. Apparatus according to claim 1 wherein the jaw
`members are substantially equiangularly spaced about the
`axis and the included angle of each V-shaped portion is
`substantially equal
`to the angular spacing between ad-
`jacent jaw members.
`5. Apparatus according to claim 1 wherein the means
`for moving the jaw members comprises a cylinder coaxial
`with said axis, a chuck mounted in said cylinder, said
`jaw members being radially slidable in said chuck and
`said chuck and said jaw members being provided with
`cooperating camming surfaces whereby longitudinal
`movement of said chuck within said cylinder in a forward
`direction moves said jaw members radially inwardly and
`toward said axis and movement of said chuck in a rear-
`ward direction causes said jaws to retract outwardly, and
`hydraulic means for moving said chuck longitudinally
`with respect to said cylinder.
`6. Apparatus according to claim 5 wherein an adjust-
`able stop is provided to limit the rearward movement of
`said chuck thereby limiting the retracting movement of
`said jaws.
`7. Apparatus for pointing tubes comprising a cylinder
`having an open end, a chuck mounted in said cylinder
`and coaxial therewith, hydraulic means for moving said
`chuck axially with respect to said cylinder; a plurality
`of jaw members substantially equiangularly spaced about
`the axis of said cylinder, said jaw members being radially
`slidable in said chuck and being restrained against axial
`movement within said cylinder, said jaw members and
`said chuck being provided with cooperating camming
`surfaces whereby axial movement of said chuck within
`said cylinder
`in a forward direction moves said jaw
`members radially inwardly toward said axis and move-
`ment of said chuck in a rearward direction causes said
`jaws to retract outwardly from said axis; an adjustable
`stop disposed at the end of said cylinder opposite said
`open end to limit the rearward movement of said chuck
`thereby limiting the retracting movement of said jaw
`members, each of said jaw members having an inner V-
`shaped portion adapted to engage the wall of a tube to be
`pointed, the V-shaped portions pointing radially inwardly
`toward said axis and being formed by plane surfaces ex-
`tending parallel to said axis and each of said members
`having a series of axially spaced, sharp,
`tube-engaging
`projections formed by the intersection of said planes, the
`
`Page 7 of 8
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`Page 7 of 8
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`

`
`7
`jaw members ‘being relieved between said projections to
`provide substantially flat tube wall engaging surfaces be-
`tween the projections.
`8. The method of cold-forming points on metal tubes
`which includes the steps of disposing a plurality of jaw
`members about an axis with the members substantially
`V equiangularly spaced about the axis,
`the jaw members
`having radially inwardly pointing V-shaped portions
`adapted to engage a tube, the jaw members each having
`a series of longitudinally spaced projections separated by
`relieved portions, disposing the j_aw members with the
`spaced projections on the members radially spaced from
`the axis a distance substantially equal to the outside radius
`of a tube to be pointed, inserting the end of a tube to be
`- pointed into the space between said jaw members with
`said projections engaging the outer surface of the tube
`and locating the tube concentric with said axis, then mov-
`ing the jaw members inwardly toward said axis simul-
`taneously and at the same rate of speed, the projections
`of said jaw members initially forming indentations in 20
`
`10
`
`15
`
`3,370,451
`
`5
`
`8 ,
`said tube and retaining said tube substantially concentric
`with said axis, and continuing the inward movement of
`said V-shaped members without interruption to fold. ad-
`jacent portions ofthe tube wall toward each other until
`the wall portions are substantially in engagement with
`each other without substantially reducing the wall and .
`provide radially extending ribs defining intermediate
`flutes, and thereafter retracting said jaw members and
`releasing said tube therefrom.
`
`References Cited
`UNITED STATES PATENTS
`8/ 1940 Hunziker __________ __ 7~2—402
`8/ 1961 Woolley __________ __ 72—402
`9/1961 Ewart ____________ __ 72-402
`11/1964 Baker _______________ 72—402
`
`2,211,622
`2,997,911
`2,999,405
`3,154,978
`
`CHARLES W. LANHAM, Primary Examiner.
`R. D. GREFE, Assistant Examiner.
`
`Page 8 of 8
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`Page 8 of 8