Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
  • B21H—MAKING PARTICULAR METAL OBJECTS BY ROLLING, e.g. SCREWS, WHEELS, RINGS, BARRELS, BALLS
  • B21H1/00—Making articles shaped as bodies of revolution
  • B21H1/18—Making articles shaped as bodies of revolution cylinders, e.g. rolled transversely cross-rolling
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
  • B21B—ROLLING OF METAL
  • B21B1/00—Metal-rolling methods or mills for making semi-finished products of solid or profiled cross-section; Sequence of operations in milling trains; Layout of rolling-mill plant, e.g. grouping of stands; Succession of passes or of sectional pass alternations
  • B21B1/16—Metal-rolling methods or mills for making semi-finished products of solid or profiled cross-section; Sequence of operations in milling trains; Layout of rolling-mill plant, e.g. grouping of stands; Succession of passes or of sectional pass alternations for rolling wire rods, bars, merchant bars, rounds wire or material of like small cross-section
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
  • B21H—MAKING PARTICULAR METAL OBJECTS BY ROLLING, e.g. SCREWS, WHEELS, RINGS, BARRELS, BALLS
  • B21H3/00—Making helical bodies or bodies having parts of helical shape
  • B21H3/10—Making helical bodies or bodies having parts of helical shape twist-drills; screw-taps
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
  • B21K—MAKING FORGED OR PRESSED METAL PRODUCTS, e.g. HORSE-SHOES, RIVETS, BOLTS OR WHEELS
  • B21K5/00—Making tools or tool parts, e.g. pliers
  • B21K5/02—Making tools or tool parts, e.g. pliers drilling-tools or other for making or working on holes
  • B21K5/04—Making tools or tool parts, e.g. pliers drilling-tools or other for making or working on holes twisting-tools, e.g. drills, reamers
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B22—CASTING; POWDER METALLURGY
  • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
  • B22F3/00—Manufacture of workpieces or articles from metallic powder characterised by the manner of compacting or sintering; Apparatus specially adapted therefor ; Presses and furnaces
  • B22F3/18—Manufacture of workpieces or articles from metallic powder characterised by the manner of compacting or sintering; Apparatus specially adapted therefor ; Presses and furnaces by using pressure rollers
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B22—CASTING; POWDER METALLURGY
  • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
  • B22F5/00—Manufacture of workpieces or articles from metallic powder characterised by the special shape of the product
  • B22F5/10—Manufacture of workpieces or articles from metallic powder characterised by the special shape of the product of articles with cavities or holes, not otherwise provided for in the preceding subgroups
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B28—WORKING CEMENT, CLAY, OR STONE
  • B28B—SHAPING CLAY OR OTHER CERAMIC COMPOSITIONS; SHAPING SLAG; SHAPING MIXTURES CONTAINING CEMENTITIOUS MATERIAL, e.g. PLASTER
  • B28B11/00—Apparatus or processes for treating or working the shaped or preshaped articles
  • B28B11/003—Apparatus or processes for treating or working the shaped or preshaped articles the shaping of preshaped articles, e.g. by bending
  • B28B11/006—Making hollow articles or partly closed articles
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B22—CASTING; POWDER METALLURGY
  • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
  • B22F2998/00—Supplementary information concerning processes or compositions relating to powder metallurgy
  • B22F2998/10—Processes characterised by the sequence of their steps

Definitions

• the invention relates to a method and an apparatus for producing a circular-cylindrical body consisting of plastic mass, in particular a sintered metal blank having at least one helical inner recess extending in the interior of the body, according to the preamble of patent claim 1 or the patent claim 7th
• Such bodies are needed in particular in the production of drilling tools or drilling tool inserts made of hard metal or ceramic materials. Due to the helical profile of the at least one inner recess, which serves in the finished drilling tool for supplying coolant or lubricant in the cutting area, the drilling tool can be equipped with helical flutes, which is often sought to provide favorable cutting and chipping properties of advantage and therefore.
• the mass issuing from the die is generally very sensitive to pressure, i. H.
• the emerging blank deforms extremely easily when exposed to external forces. Since such deformations are no longer reversible and thus lead to at least partially useless blanks, it has been attempted to further develop the extrusion process so that the blank already has consultediförmig extending cooling channels when exiting the extrusion die. According to a proposal (see, for example, EP-A-0 465 946), this is achieved by providing helical guide strips on the inner circumference of the extrusion die, which impose a swirling movement on the emerging plastic mass.
• the nozzle mouthpiece and / or a hub shaped like a propeller, to which the abovementioned flexible limbs are attached are set into rotary motion during the extrusion process, which in turn produces an outer smooth blank with inner helical channels or recesses can be produced.
• a method and an apparatus for producing a sintered metal blank having internal helical recesses are already known.
• a substantially circular-cylindrical body is produced, for example extruded, by means of at least one internal recess running rectilinearly in its interior.
• This body is cut to a desired length and then subjected to rolling over its entire length on a support by means of a friction surface arrangement, whose velocity changes linearly and steadily over the length of the body, whereby the body is twisted uniformly.
• This twisting is done using an axis of rotation that intersects the longitudinal axis of the body.
• the object of the invention is therefore to provide a method and an apparatus for producing a circular mass consisting of plastic mass body, which is or these higher requirements.
• the advantages of the invention are in particular that by means of the claimed method of plastic mass existing circular cylindrical body can be produced, at least one helical inner recess over the entire length of the body has an extremely constant, held within very narrow tolerated limits helix angle.
• This advantage is based on the fact that the individual longitudinal sections of the circular cylindrical body each travel the same way during the rolling process.
• the individual longitudinal sections of the circular-cylindrical body travel paths of different lengths.
• the paths which cover longitudinal sections located close to the axis of rotation during the rolling process are comparatively small, while those longitudinal sections which are arranged away from the axis of rotation cover comparatively large paths during the rolling process.
• FIG. 1 shows a plan view of an embodiment of a device for producing a sintered metal blank made of a plastic mass with an internal recess according to the prior art
• FIG. 2 shows the view corresponding to II in FIG. 1
• FIG. 3 in a view corresponding to FIG
• Figure 4 is a sketch illustrating the change of the axis of rotation during the rolling motion in the inventive method
• Figure 5 is a sketch illustrating an apparatus for performing the method according to the invention.
• FIGS. 1 to 3 denoted by reference numeral 10 is a cut to a predetermined length L *; H.
• Sintered sintered metal blank referred to, for example, from a hard metal powder with kneaded Binde dimensions Adhesive exists.
• This sintered metal blank is produced for example by extrusion, in such a way that it has a straight and continuous, shown in the figures with a dotted line inner recess 12 which extends parallel to the center axis 14 of the circular cylindrical blank 10.
• the production of the sintered metal blank is preferably carried out in the extrusion process with the aid of an extrusion die with a suitable core.
• the blank 10 has a relatively soft consistency, so that the handling, such. As the transport, must be done very carefully to prevent irreversible deformation. Therefore, the blank is preferably performed immediately after exiting the extrusion die on an air cushion and directed to the pad 16 shown in the figures, which coincides in Figures 1 and 3 with the display plane.
• the blank is due to the consistency of the extruded mass on its outside sticky, so that a good adhesion with the support surface 16 results.
• a circular segment disc 18 is arranged with a friction surface 20 on the bottom side.
• the circular segment disc 18 is rotatable about an axis of rotation 22 which is perpendicular to the surface of the support 16 and on the friction surface.
• the vertical distance AV between the surfaces 16 and 20 is preferably adjustable, which is indicated by the double arrow V in Figure 2. This vertical distance AV corresponds to the diameter D of the blank 10.
• the blank 10 is placed on the support 16, that its longitudinal axis 14, the axis of rotation 22 of the circular segment disc 18 intersects. Subsequently, the circular segment disc is lowered controlled so that it touches the blank 10 along a line which is offset diametrically to the bottom-side contact line of the blank 10 with the support 16. This orientation is shown in FIGS. 1 and 2.
• the circular segment disc 18 is pivoted at an angular velocity ⁇ . Due to the frictional contact between see the surface 20 of the circular segment disc 18 and the blank 10, the blank is taken by rolling on the surface of the support 16 at a speed that changes linearly and steadily along the axis of the blank 10.
• the rolling speed at the inner end of the blank 10 is VWI and the rolling speed at the outer end of the blank 10 is designated VWA.
• the circular segment disc 18 is held in contact with the rod-shaped blank 10 with as low a bearing force as possible, during the entire twisting operation, ie. H. during the entire pivoting about the pivoting angle ⁇ (see Fig. 3).
• pressure sensors which act on the not shown lifting and lowering device for the circular segment disc 18.
• a change in the axis of rotation takes place in the present invention during the rolling process.
• This change in the axis of rotation takes place in particular such that all longitudinal sections of the blank during the rolling process each cover the same rolling distance.
• the rolling process preferably takes place in two successive steps, wherein in the first step a rolling movement takes place about a first axis of rotation and in the second step a rolling movement about a second axis of rotation takes place.
• a method according to the invention is as well as the method known from EP-B1-I 230 046 for producing a circular cylindrical body consisting of plastic mass, in particular a sintered metal blank, which has at least one helical inner recess running in the interior of the body.
• the body is first produced with a straight course of the inner recess, for example extruded.
• the extruded body is cut to a desired length. Subsequently, it is subjected to a rolling process with support over its entire length on a support with a friction surface arrangement, so that a twisting of the body takes place.
• the rolling process takes place in two successive steps, wherein in the first step, a rolling movement about a first axis of rotation and in the second step, a rolling movement about a second axis of rotation, wherein the second axis of rotation is different from the first axis of rotation.
• the rolling process takes place in such a way that each longitudinal section of the circular-cylindrical body travels the same path during the rolling process. The Rolling direction is maintained in the successive steps.
• the positioning of the axes of rotation is such that during the first step, the axis of rotation intersects the center line of the circular cylindrical body in the region of an axial end surface of the circular cylindrical body and during the second step, the axis of rotation of the center line of the circular cylindrical body in the area the other axial end surface of the circular cylindrical body intersects.
• the positioning of the axes of rotation is such that during the first step, the axis of rotation cuts the extended center line of the circular cylindrical body at a predetermined distance from an axial end surface of the circular cylindrical body and during the second step the rotation axis intersects the extended centerline of the circular cylindrical body at the same predetermined distance from the other axial end surface of the circular cylindrical body.
• Another embodiment of the invention is to change the axis of rotation about which the rolling movement occurs during the rolling movement several times or continuously.
• FIG. 4 shows a sketch to illustrate the change of the axis of rotation during the rolling process.
• the circular cylindrical body 10 is in the position in which it is shown with the reference number 10.
• a twisting of the body using the Rotary axis Dl which is perpendicular to the plane of the drawing.
• the body is moved through an angle denoted by " ⁇ " in the vicinity of the rotation axis D1 in Figure 4.
• the rotation axis Dl intersects the center line M of the circular cylindrical body at a predetermined distance from an axial end portion
• the velocity changes linearly and steadily over the length of the body, and at the end of the first step, the body is at a position offset by the angle ⁇ , where it is indicated by reference numeral 10 '.
• a second step the body is twisted using a rotation axis D2. This also runs perpendicular to the drawing plane.
• the rotation axis D2 intersects the center line M 'of the circular cylindrical body 10' at a predetermined distance from the other axial end surface of the circular cylindrical body.
• the body is moved through an angle which is also denoted by " ⁇ " in the vicinity of the rotation axis D2 in Fig. 4. Also in this twisting, the velocity changes linearly and steadily over the length of the body of the second step, the body is in a position offset by the angle ⁇ , where it is provided with the reference numeral 10 ".
• the entire twisting process is adapted to the effect that the different longitudinal sections of the circular-cylindrical body during the entire twisting process each travel the same distance or twisting distance. This is illustrated in FIG. 4 on the basis of the longitudinal sections A1 and A2 of the circular-cylindrical body.
• the longitudinal section Al of the circular-cylindrical body is moved in the first step by the distance indicated by sl in FIG. After completion of the first step tes is this longitudinal section in the body 10 'and is there denoted by Al'.
• the longitudinal section A2 of the circular-cylindrical body is moved in the first step by the distance indicated in FIG. 4 by s2. After completion of the first step, this longitudinal section is located in the body 10 'and is designated there by A2'.
• the longitudinal section A2 ' is moved by the distance designated by s2' in FIG. After completion of the second step, this longitudinal section is located in the body 10 "and is designated there by A2".
• the total distance is therefore:
• W2 s2 + s2 '.
• FIG. 5 shows a sketch to illustrate a device for carrying out the method according to the invention.
• This device has a flat support surface 16.
• a Wälzin 23 is arranged in the vertical distance AV to this .
• This has a contact surface-side friction surface 24.
• the Wälzogen 23 is rotatable about an axis of rotation 25 which is perpendicular to the surface of the support surface 16. This rotation takes place at an angular velocity ⁇ .
• the vertical distance AV between the support surface 16 and the rolling disk 23 is adjustable, as indicated by the double arrow V is tet.
• the rolling movement takes place using the axis of rotation 25.
• the rolling movement takes place using a second axis of rotation 26, which is also perpendicular to the surface of the support surface 16. This rotation also takes place at the angular velocity ⁇ .
• the rolling direction in the second step coincides with the rolling direction in the first step.

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• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• Manufacturing & Machinery (AREA)
• Structural Engineering (AREA)
• Chemical & Material Sciences (AREA)
• Ceramic Engineering (AREA)
• Powder Metallurgy (AREA)
• Rolling Contact Bearings (AREA)
• Forging (AREA)
• Physical Vapour Deposition (AREA)
• Shaping By String And By Release Of Stress In Plastics And The Like (AREA)
• Shafts, Cranks, Connecting Bars, And Related Bearings (AREA)

Applications Claiming Priority (2)

Publications (2)

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Family Applications (1)

Country Status (9)

Cited By (1)

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• 2008
  • 2008-07-16 DE DE102008033413A patent/DE102008033413A1/de not_active Withdrawn
• 2009
  • 2009-06-18 JP JP2011517837A patent/JP5453414B2/ja active Active
  • 2009-06-18 EP EP09779827A patent/EP2313218B1/fr active Active
  • 2009-06-18 CN CN2009801273681A patent/CN102099134B/zh active Active
  • 2009-06-18 WO PCT/EP2009/057583 patent/WO2010006873A1/fr active Application Filing
  • 2009-06-18 AT AT09779827T patent/ATE529206T1/de active
  • 2009-06-18 KR KR1020117001088A patent/KR101264755B1/ko active IP Right Grant
  • 2009-06-18 ES ES09779827T patent/ES2373634T3/es active Active
  • 2009-06-18 US US12/737,444 patent/US8850861B2/en active Active
• 2014
  • 2014-08-28 US US14/471,318 patent/US9044797B2/en active Active

Non-Patent Citations (1)

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