US1922498A - Method and machine for making wire-drawing dies, etc. - Google Patents

Method and machine for making wire-drawing dies, etc. Download PDF

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Publication number
US1922498A
US1922498A US530912A US53091231A US1922498A US 1922498 A US1922498 A US 1922498A US 530912 A US530912 A US 530912A US 53091231 A US53091231 A US 53091231A US 1922498 A US1922498 A US 1922498A
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machine
spindle
drill
hole
work
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US530912A
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John E Peterson
Emil A Van Beke
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EISLER ELECTRIC Corp
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EISLER ELECTRIC CORP
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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B24GRINDING; POLISHING
    • B24BMACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS
    • B24B5/00Machines or devices designed for grinding surfaces of revolution on work, including those which also grind adjacent plane surfaces; Accessories therefor
    • B24B5/36Single-purpose machines or devices
    • B24B5/48Single-purpose machines or devices for grinding walls of very fine holes, e.g. in drawing-dies

Definitions

  • the method and machine of our invention accomplishes all of the above and other important operations in a single set-up of the machine and of the work-piece toproduce a perfectly formed and polished hole.
  • Fig. 1 is a front elevation of the machine;
  • Fig. 2 is a side view thereof;
  • Fig. 3 is the same as Fig. 1 except that the rotary table and relatrd parts are shown in vertical cross-- section and the tilting head is shown only in its vertical or middle position. also the polishing wire and its connections are shown;
  • Fig. '4 is an enlarged view in vertical cross-section of a portion of the'turntable. and the drawing-die shown in the other figures in which the hole is being drilled in accordance with our invention, said figure serving to illustrate the co-action of the drill with the work-piece at various times as the work progresses as will be hereinafter explained.
  • the machine in general comprises a drill spindle 1 suitably supported so as to be tilted from a vertical position into an angular position relatively to the work-piece A, and further comprises a rotary table 2 for the support of the work-piece to be drilled, formed and polished; and further comprises a specially constructed hollow spindle 3 for supporting the rotary table having combined therewith means for receiving a wire l through the hollow of the spindle, the lower end of said .wire being swivelled and yieldingly attached to a fixed part of the underneath framework of the machine, and its upper end, which projects through the hollow spindle and the hole in the work-piece, being secured in the chuck 5 of the drill spindle so that thelwire rotates with the spindle.
  • This turntable spindle is a hollow tube 3 which has an outwardly extending flange or shoulder 3*- at its upper end overlying the upper end of the bearing '1. Its lower end projecting below the bearing supports a pulley 8 keyed thereto.
  • the rotary turntable 2 has a center hole through it in communication with a hole through a hollow stem 2 integral with the bottom of the turntable. In the particular form shown, this stem is conical and is fixed in the mouth of a tube 3 contained within the previously described hollow spindle 3. There is a sliding fit between this tube and the spindle; and means is provided for longitudinally adjusting the tube.
  • said adjusting means comprising screwthreads 3 on the outside of the tube in engagement with other screw-threads on the inside of the rotary spindle.
  • This adjusting means further comprises a knurled head 3 on the tube by which the operator of the machine can screw the slidable tube 3 into and out of the rotary spindle 3 to a greater or less extent and so adjust the height of the turntable to any desired position relatively to v is pivotally supported at 9 from the framework 6 of the machine so that the entire head can be caused to sway laterally from side to side or to occupy any suitable angular position between the vertical position shown by the full .lines in Fig.
  • the drill head 9 is provided as shown with two relatively to the toe of the rock-arm 18.
  • Means for driving respectively the drillspindle and the turntable spindle, the former by means of the belt 11 engaging the grooved pulley 10 and the latter by the belt 12 engaging the grooved pulley 8 previously described.
  • These speeds may be varied in practice but we have found that a speed of 1000 R. P. M. for the drill spindle l and a speed 'of 200 R.P.M. in an opposite direction for the turntable 2 gives good results.
  • These speeds may be varied in accordance with the type of the material to be worked. The revolving of the material to be.
  • the drill-spindle 1 can move vertically while rotating in its'bearings; and that it is given sufficient weight so that it constantly tends to force the drill against the work with the requisite pressure.
  • Means for continuously swaying or oscillating the spindle head about its pivot 9 through an are which is adjustable as to its length or throw.
  • the machine comprises a crank-driven connecting-rod 14 whose ends are pivotally connected respectively to the upper part of the drill-head and to the crank pin.
  • the crank illustrated takes the form of a rotary disk 15 or wheel supported for rotation in suitable bearings by the frame of the machine and having suitable driving connections thereto for rotating it comprising a worm-wheel 21 fixed to or rotatable with the disk 15 and a belt and pulley-driven worm 22.
  • crank pin 15 forms part of a block 15 which is slidable across the face of the disk between a pair of guides 15 and is securable in any desired position of adjustment along said guides to vary the throw of the crank and.the oscillation-arc of the drill-head. 4
  • -In additionv means which automatieally and intermittently raisesand lowers the drill spindle and the drill relatively to the turntable and the work-piece while the machine is in 'operation. This up and down motion takes place many times during each sway of the spindle-head.
  • the means comprises a rotary-cam 16 suitably supported on the side of the drill-head driven by a'pulley 17 on the same shaft belted to a suitable motor means (not shown) This cam engages the heel of a rock-arm .18 pivoted intermediate its ends to the drill-head with its toe 18 extending under the drive pulley-10 on the drill spindle,
  • the die or work-piece A'to be drilled is secured ormounted on the turntable 2 in any desired or preferred manner; and comprises the usual metallic casing "A rigidly enclosing the diamond or other hard substance A which is to be drilled and A hole having been bored through the top of the metallic casing A with any 'suitablemachine tool down to the diamond A the work-piece is then centered on and aflixed to the turntable with said hole uppermost.
  • Thecrank pin 15 is then adjusted to the center of its disk or approximately so.
  • the knurled head 3 is operated to adjust the height of the turntable and the work-piece as well as the height of the drill B and the drill spindle lresting. upon it so that the up and down motion delivered by the rock-arm 18 is minimized.
  • Suitable abrasive powder having then been applied.
  • the machine is set in motion and the oppositely rotating drill and work-piece drill a vertical hole in the diamond.
  • Fig. 4 shows in cross-section a completely drilled, formed and polished die A produceable by this machine in a single set-up.
  • the lead-1n cone on the front of the die can be varied in slope and contour by suitably adjusting the throw of the crank and the oscillation-arc 'of the drill spindle.
  • B and B 'in Fig. 4 indicate two of the many positions of the tool during its up and down and laterally swaying movements to form the lead-in cone.
  • the over-all size and depth of the cone is also under control, including the adjustment of the height of the turntable by means of the knurled head 3'.
  • the drilling and polishing of the wall of the hole' may be carried out by disconnecting the swaying attachment and operating the drill spindle as a simple revolvingspindle simultaneously with the other devices.
  • the drilling, forming and polishing of the relieving-cone on the back of the die is provided by suitably adjusting and operating the swaying attachment of the drill spindle and two of the positions of the vided usuable whenever desirable for polishing and finishing the interior surface of the hole with a rotary wire 4.
  • the wire 4 is passed through the hollow turntable spindle and through the hole in the work-piece.
  • the upper end of the wire is secured in the chuck of the drill spindle; and its lower end is secured to the rotary member 19 of a swivel whose outer relatively stationary part 19 is secured to a coiled tension spring 20 attached to a portion of the underneath framework of the machine.
  • the machine is then set in'motion, whereupon the wire-is rapidly rotated about its own axis and is brought into rubbing contact with the walls of the hole in the work-piece by the lateral swaying of the drill head; and moreover, at the same time the wire is caused by the rockarm 18 to slide up and down in contact with the wall of the hole as permitted by the spring 20.
  • the illustrated machine shows only a singleunit drill spindle. However, in practice, multiples of the devices shown have been combined in one machine with interconnections between them whereby ten or more work-pieces canbe drilled simultaneously by a single operator.
  • the turntable has an axial hole or opening 2 in continuation of or under the hole through'the die or other article which is being formed so that the point of the tool B during the up and down and swaying movements of the tool can play freely through the hole in the workpiece into the turntable opening without any 1.
  • a work-supporting rotary 1 table having a hollowstein and a communicating axial hole through the table; a machine head supported to swing about an axis adjacent the level of the work-piece on the table; a spindle journaled for rotation in said machine head as Well as for simultaneous endwise movement towards and away from the rotary table; a wire extending through the hole in the table and its hollow stem, said wire being attached by its upper end to the spindle and having its lower end anchored with provision for yielding in directions endwise of said wire and for swivelling; means co-operating with said spindle which intermittently effects its endwise movement; and means for swinging the machine 'head as aforesaid.
  • a work-supporting rotary table having a hollow stem and a communicating axial hole through the table; a machine head supported to swing about an axis adjacent the level of the work-piece on the table; a spindle journaled for rotation in the machine head as well as for simultaneous endwise movement towards and away from the rotary table; a wire extending through the hole in the table and its hollow stem, said wire being attached by its upper end to said spindle and having its lower end anchored for swiv'elling and tensioned by means of a spring; means co-operating with said spindle which intermittently lifts and releases it against the tension of said spring; and means for swinging the machine head as aforesaid.

Description

Aug. 15, 1933. .1. E. PETERSON El AL 1,922,498
METHOD [AND MACHINE FOR MAKING WIRE DRAWING DIES, ETC
Original Filed July 21, 1930 INVEN210 S i an 2 1%; A. ZZZ/re I Patented- Aug. 15, 1933,
UNITED STATES PATENT OFFICE METHOD AND MACHINE Fort" MAKING 'WIRE-DRAWING mes, ETC.
ware
Originalapplication July 21, 1930, Serial No.
Divided and this application April 17,
1931. Serial No. 530,912
2 Claims. (Cl. 51-32) Our present invention relates to a method and machine for making wire-drawing dies, etc. and isjadivision from our co-pending United States patent application of the same title, Serial No.
469,381 filed July 21, 1930. That application discloses a method and machine for drilling, forming and polishing holes in hard substances and materials such as diamonds and other precious and semi-precious stones, glass, refractory metals and other materials where it is necessary to have the holes drilled or formed or polished or to have any combination of drilling, forming or polishing,--but the claims are directed to the drilling portion of the invention,.whereas the claimsin the present case are directed to the polishing portion of the invention. In both cases, the dis-- closure on account of the inter-related nature of the claimed subject matter is substantially the same both as to specification and drawing as follows:
The prior art method in common use for drillof the hole; and polishing and finishing it. These operations, performed in separate stages, require a separate set-up of the machine and the workpiece for each stage, with resulting inaccuracies in the form of the hole as well as loss of time.
The method and machine of our invention accomplishes all of the above and other important operations in a single set-up of the machine and of the work-piece toproduce a perfectly formed and polished hole.
' The accompanying drawing shows diagrammatically one preferred embodiment of a,machine within our invention; and said drawing and the following description serve to illustrate the. invention but without limiting the invention to the details thereof except as called for by the claims.
In the drawing, Fig. 1 is a front elevation of the machine; Fig. 2 is a side view thereof; Fig. 3 is the same as Fig. 1 except that the rotary table and relatrd parts are shown in vertical cross-- section and the tilting head is shown only in its vertical or middle position. also the polishing wire and its connections are shown; and Fig. '4 is an enlarged view in vertical cross-section of a portion of the'turntable. and the drawing-die shown in the other figures in which the hole is being drilled in accordance with our invention, said figure serving to illustrate the co-action of the drill with the work-piece at various times as the work progresses as will be hereinafter explained.
The machine in general comprises a drill spindle 1 suitably supported so as to be tilted from a vertical position into an angular position relatively to the work-piece A, and further comprises a rotary table 2 for the support of the work-piece to be drilled, formed and polished; and further comprises a specially constructed hollow spindle 3 for supporting the rotary table having combined therewith means for receiving a wire l through the hollow of the spindle, the lower end of said .wire being swivelled and yieldingly attached to a fixed part of the underneath framework of the machine, and its upper end, which projects through the hollow spindle and the hole in the work-piece, being secured in the chuck 5 of the drill spindle so that thelwire rotates with the spindle. 1
Only a portion of the stationary framework 6 of the machineis shown. A bracket 7 secured to this framework supports the bearing 7 of the turntable spindle. This turntable spindle is a hollow tube 3 which has an outwardly extending flange or shoulder 3*- at its upper end overlying the upper end of the bearing '1. Its lower end projecting below the bearing supports a pulley 8 keyed thereto. The rotary turntable 2 has a center hole through it in communication with a hole through a hollow stem 2 integral with the bottom of the turntable. In the particular form shown, this stem is conical and is fixed in the mouth of a tube 3 contained within the previously described hollow spindle 3. There is a sliding fit between this tube and the spindle; and means is provided for longitudinally adjusting the tube.
and, therefore, the turntable which it supports for a limited distance up and down in the hollow spindle, said adjusting means comprising screwthreads 3 on the outside of the tube in engagement with other screw-threads on the inside of the rotary spindle. This adjusting means further comprises a knurled head 3 on the tube by which the operator of the machine can screw the slidable tube 3 into and out of the rotary spindle 3 to a greater or less extent and so adjust the height of the turntable to any desired position relatively to v is pivotally supported at 9 from the framework 6 of the machine so that the entire head can be caused to sway laterally from side to side or to occupy any suitable angular position between the vertical position shown by the full .lines in Fig. l and the dotted lines in the same figure in order to adjust correspondingly, the angular position of the drill B relatively to the work-piece'in boring a hole therethrough and in forming'ancl shaping the wall of said hole. Massive lateral extensions 9-9 from the drill-head adjacent the pivot 9 lower its center of gravity and tend to prevent vibration.
The drill head 9 is provided as shown with two relatively to the toe of the rock-arm 18.
Means, not necessary to illustrate, is provided for driving respectively the drillspindle and the turntable spindle, the former by means of the belt 11 engaging the grooved pulley 10 and the latter by the belt 12 engaging the grooved pulley 8 previously described. These speeds may be varied in practice but we have found that a speed of 1000 R. P. M. for the drill spindle l and a speed 'of 200 R.P.M. in an opposite direction for the turntable 2 gives good results. These speeds may be varied in accordance with the type of the material to be worked. The revolving of the material to be.
drilled in an opposite direction from and simultaneously with the drill-point has been found to have an advantageous effect in producing a perfectly round, formed and polished hole.
It will be understood that the drill-spindle 1 can move vertically while rotating in its'bearings; and that it is given sufficient weight so that it constantly tends to force the drill against the work with the requisite pressure.
Means is provided for continuously swaying or oscillating the spindle head about its pivot 9 through an are which is adjustable as to its length or throw. For this purpose, the machine comprises a crank-driven connecting-rod 14 whose ends are pivotally connected respectively to the upper part of the drill-head and to the crank pin. The crank illustrated takes the form of a rotary disk 15 or wheel supported for rotation in suitable bearings by the frame of the machine and having suitable driving connections thereto for rotating it comprising a worm-wheel 21 fixed to or rotatable with the disk 15 and a belt and pulley-driven worm 22. The crank pin 15 forms part of a block 15 which is slidable across the face of the disk between a pair of guides 15 and is securable in any desired position of adjustment along said guides to vary the throw of the crank and.the oscillation-arc of the drill-head. 4
-In additionv means is provided which automatieally and intermittently raisesand lowers the drill spindle and the drill relatively to the turntable and the work-piece while the machine is in 'operation. This up and down motion takes place many times during each sway of the spindle-head. The means comprises a rotary-cam 16 suitably supported on the side of the drill-head driven by a'pulley 17 on the same shaft belted to a suitable motor means (not shown) This cam engages the heel of a rock-arm .18 pivoted intermediate its ends to the drill-head with its toe 18 extending under the drive pulley-10 on the drill spindle,
formed intothe die, etc.
which latter, it will be understood, is slidable up and down in its bearings. Thus, for each rotation of the cam, the drill spindle and the drill will be raised by the rock-arm and then lowered by the previously referred to means that gives it down- 'ward tendency, such as the weight of the drillspindle takes place simultaneously with its own rotation and .the rotation of the work-piece and'' with the controllable and adjustable swaying of the drill-head; and thereby enables the wall of the hole to be formed with the desired contour. The extent of this up and down motion may be adjusted by using the set-screw 10 of the pulley 10 to adjust the position of the pulley relatively to thetoe of the rock-arm 18. g
The die or work-piece A'to be drilled is secured ormounted on the turntable 2 in any desired or preferred manner; and comprises the usual metallic casing "A rigidly enclosing the diamond or other hard substance A which is to be drilled and A hole having been bored through the top of the metallic casing A with any 'suitablemachine tool down to the diamond A the work-piece is then centered on and aflixed to the turntable with said hole uppermost. Thecrank pin 15 is then adjusted to the center of its disk or approximately so. The knurled head 3 is operated to adjust the height of the turntable and the work-piece as well as the height of the drill B and the drill spindle lresting. upon it so that the up and down motion delivered by the rock-arm 18 is minimized. Suitable abrasive powder having then been applied. the machine is set in motion and the oppositely rotating drill and work-piece drill a vertical hole in the diamond. Gradually more and more sway isimparted to the drill head by suitably adjusting the position of the crank pin. Also, the extent of the up and downmovement of the drill spindle and drill is increased.
Fig. 4 shows in cross-section a completely drilled, formed and polished die A produceable by this machine in a single set-up. The lead-1n cone on the front of the die can be varied in slope and contour by suitably adjusting the throw of the crank and the oscillation-arc 'of the drill spindle. B and B 'in Fig. 4 indicate two of the many positions of the tool during its up and down and laterally swaying movements to form the lead-in cone. The over-all size and depth of the cone is also under control, including the adjustment of the height of the turntable by means of the knurled head 3'. The drilling and polishing of the wall of the hole'may be carried out by disconnecting the swaying attachment and operating the drill spindle as a simple revolvingspindle simultaneously with the other devices. The drilling, forming and polishing of the relieving-cone on the back of the die is provided by suitably adjusting and operating the swaying attachment of the drill spindle and two of the positions of the vided usuable whenever desirable for polishing and finishing the interior surface of the hole with a rotary wire 4. After the holehas been .bored through the work-piece and it is ready for polishing by this method, the wire 4 is passed through the hollow turntable spindle and through the hole in the work-piece. The upper end of the wire is secured in the chuck of the drill spindle; and its lower end is secured to the rotary member 19 of a swivel whose outer relatively stationary part 19 is secured to a coiled tension spring 20 attached to a portion of the underneath framework of the machine. The machine is then set in'motion, whereupon the wire-is rapidly rotated about its own axis and is brought into rubbing contact with the walls of the hole in the work-piece by the lateral swaying of the drill head; and moreover, at the same time the wire is caused by the rockarm 18 to slide up and down in contact with the wall of the hole as permitted by the spring 20. The net result of all of these motions is highly efiicient polishing action by the wire upon the wall of the hole. This operation of finishing the surface of the hole can also be accomplished in other ways,-for example, by not rotating the drill spindle or the wire and by rotating only the turntable and the work-piece; or vice versa by rotating the drill spindle and the wire but holding stationary the work-piece and the turntable; or by the combination of the two as at first described.
The illustrated machine shows only a singleunit drill spindle. However, in practice, multiples of the devices shown have been combined in one machine with interconnections between them whereby ten or more work-pieces canbe drilled simultaneously by a single operator.
It will be noted that the turntable has an axial hole or opening 2 in continuation of or under the hole through'the die or other article which is being formed so that the point of the tool B during the up and down and swaying movements of the tool can play freely through the hole in the workpiece into the turntable opening without any 1. In combination, a work-supporting rotary 1 table having a hollowstein and a communicating axial hole through the table; a machine head supported to swing about an axis adjacent the level of the work-piece on the table; a spindle journaled for rotation in said machine head as Well as for simultaneous endwise movement towards and away from the rotary table; a wire extending through the hole in the table and its hollow stem, said wire being attached by its upper end to the spindle and having its lower end anchored with provision for yielding in directions endwise of said wire and for swivelling; means co-operating with said spindle which intermittently effects its endwise movement; and means for swinging the machine 'head as aforesaid.
2. In combination, a work-supporting rotary table having a hollow stem and a communicating axial hole through the table; a machine head supported to swing about an axis adjacent the level of the work-piece on the table; a spindle journaled for rotation in the machine head as well as for simultaneous endwise movement towards and away from the rotary table; a wire extending through the hole in the table and its hollow stem, said wire being attached by its upper end to said spindle and having its lower end anchored for swiv'elling and tensioned by means of a spring; means co-operating with said spindle which intermittently lifts and releases it against the tension of said spring; and means for swinging the machine head as aforesaid.
' JOHN E. PETERSON. EMIL A. VAN BEKE.
US530912A 1930-07-21 1931-04-17 Method and machine for making wire-drawing dies, etc. Expired - Lifetime US1922498A (en)

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US469381A US1922497A (en) 1930-07-21 1930-07-21 Method and machine for making wire-drawing dies, etc.
US530912A US1922498A (en) 1930-07-21 1931-04-17 Method and machine for making wire-drawing dies, etc.

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Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2441003A (en) * 1945-10-03 1948-05-04 Bieberich Paul Lapping machine for wire drawing die compacts
US2450077A (en) * 1946-08-01 1948-09-28 Bieberich Paul Wire-drawing die lapping machine
US3267705A (en) * 1964-03-16 1966-08-23 United Shoe Machinery Corp Automatic roughening machines
FR2518003A1 (en) * 1981-12-14 1983-06-17 Snecma Reconditioning small diameter holes - by burnishing with wire rotating at high speed

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2441003A (en) * 1945-10-03 1948-05-04 Bieberich Paul Lapping machine for wire drawing die compacts
US2450077A (en) * 1946-08-01 1948-09-28 Bieberich Paul Wire-drawing die lapping machine
US3267705A (en) * 1964-03-16 1966-08-23 United Shoe Machinery Corp Automatic roughening machines
FR2518003A1 (en) * 1981-12-14 1983-06-17 Snecma Reconditioning small diameter holes - by burnishing with wire rotating at high speed

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