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WO2001043915A1 - Procede et dispositif pour usiner et produire des pieces structurees oblongues et arbre flexible ainsi obtenu - Google Patents

Procede et dispositif pour usiner et produire des pieces structurees oblongues et arbre flexible ainsi obtenu Download PDF

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Publication number
WO2001043915A1
WO2001043915A1 PCT/EP2000/012140 EP0012140W WO0143915A1 WO 2001043915 A1 WO2001043915 A1 WO 2001043915A1 EP 0012140 W EP0012140 W EP 0012140W WO 0143915 A1 WO0143915 A1 WO 0143915A1
Authority
WO
WIPO (PCT)
Prior art keywords
workpiece
machining
slots
tube
axis
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Ceased
Application number
PCT/EP2000/012140
Other languages
German (de)
English (en)
Inventor
Eckhard Huber
Wilfried Lehmann
Helmut Lehmann
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Sandvik AB
Original Assignee
Sandvik AB
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Sandvik AB filed Critical Sandvik AB
Publication of WO2001043915A1 publication Critical patent/WO2001043915A1/fr
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

Links

Classifications

    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B17/00—Surgical instruments, devices or methods
    • A61B17/16—Instruments for performing osteoclasis; Drills or chisels for bones; Trepans
    • A61B17/1613—Component parts
    • A61B17/1631—Special drive shafts, e.g. flexible shafts
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B24—GRINDING; POLISHING
    • B24B—MACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS
    • B24B27/00—Other grinding machines or devices
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B24—GRINDING; POLISHING
    • B24B—MACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS
    • B24B5/00—Machines or devices designed for grinding surfaces of revolution on work, including those which also grind adjacent plane surfaces; Accessories therefor
    • B24B5/36—Single-purpose machines or devices
    • B24B5/38—Single-purpose machines or devices for externally grinding travelling elongated stock, e.g. wire

Definitions

  • the present invention relates to a method and a device for processing and producing elongated, structured components, and to a flexible shaft produced therewith.
  • the method and the corresponding device from which the present invention is based relate in particular to the production of flexible shafts.
  • the method according to the invention and the corresponding device can also be used without difficulty for the production of other elongated and structured objects.
  • the scope of the present invention therefore essentially refers to a specific type of flexible shaft which is produced using corresponding methods and devices.
  • the present invention also relates to a corresponding flexible shaft itself, which is produced using the method according to the invention and the corresponding device.
  • Such a flexible shaft is used above all in the medical field and is intended to be used to move a processing tool on paths that are not exactly straight through the human body, in particular in the longitudinal direction through the large limb bones, such as for example the thigh and lower leg bones or the upper arm bones. pass therethrough.
  • Appropriate surgical measures are often necessary to heal broken bones or to anchor artificial components, such as brackets or screws, and in particular artificial joints in bones.
  • a guide wire or catheter is generally introduced into the inside of the bone on the desired path and the processing tool, which has a corresponding central bore for the guide wire at its tip and which is located at the front end of a rotatable and flexible shaft, is placed on the guide wire pushed on and moved by this on a corresponding track.
  • These flexible shafts essentially consist of a tube into which a multiplicity of parallel slots are made in the circumferential direction, with successive slots being offset relative to one another in the circumferential direction and with each of the slots over an angular range of more than 180 ° and up to extends the order of 270 °.
  • the slots are usually offset by approximately 120 ° in the circumferential direction relative to the preceding or following slot, so that the tube has essentially three different groups of slots, the slots of each group extending over the same angular range and different groups are each offset by 120 ° to each other, and in the order of the slots a slot from a first group is followed by another from the second group and preceded by a slot from the third group.
  • the slots are generally made by sawing or milling.
  • this has the disadvantage that there are often burrs, in particular on the edges and at the ends of the slots, which are not always noticed and on which, when used as intended, need the wave to accumulate the material through which the wave is passed, in the above example in particular bone marrow or bone cells.
  • the present invention is based on the object of creating a method and a device for producing and processing elongated, structured workpieces and an object produced therewith, which enable a significantly simplified manufacturing process.
  • this object is achieved by a method which has the following steps: a) clamping one of the ends of the elongated workpiece, b) moving the workpiece in its longitudinal direction into a predetermined first longitudinal position, c) rotating the workpiece about its longitudinal axis into a desired machining position, d) feeding a machining tool towards the workpiece essentially in the radial direction, e) supporting the workpiece on the side of the workpiece opposite the machining tool at least during machining by the machining tool, f) retracting the machining tool into a starting position, g) repeating steps b to f until machining has taken place at all desired positions of the elongated workpiece and h) wherein steps b and c are also interchangeable or can be carried out simultaneously.
  • the object on which the invention is based is achieved in that the device has the following features: a) a clamping device (2) for clamping one of the ends of the elongated workpiece, b) a feed device (3) for a feed movement of the clamped workpiece into a desired axial position, c) a rotating device (4) for rotating the elongated workpiece about its longitudinal axis (5), which is essentially parallel to the feed direction, and for holding the workpiece (1) in a desired rotational position, d) a processing device (6) with a processing tool (7 ), which can be adjusted essentially in the radial direction with respect to the axis of the workpiece (1) and e) a support device (8) for the workpiece (1), which is essentially on the side of the workpiece (1) opposite the machining device (6) is arranged.
  • a special object produced with such a method and a corresponding device is a flexible shaft made of a tube with slots, as has already been described above, the slots being produced by a suitable processing tool with a device according to the invention, in particular by grinding.
  • the method according to the invention and the corresponding devices allow an elongated object to be clamped at only one end, a corresponding feed device ensuring that it is moved into a desired first axial position and also rotated into a desired rotating position with the aid of a rotating device is, whereupon a processing tool is fed radially in the given position.
  • This machining tool then engages the workpiece from one side and produces the desired structure, it also being possible for a certain axial advance of the workpiece to take place in both directions of the longitudinal axis of the workpiece and also for the rotational position of the workpiece also during the Processing can be varied more or less in order to carry out the processing on a corresponding circumferential section.
  • the support device ensures that the workpiece can practically not deflect when the processing tool engages the workpiece from the opposite side.
  • the machining tool is withdrawn again in a predetermined section, and the workpiece is fed without machining into a desired new axial position in which, after the desired rotational position has been set appropriately, the machining tool can be re-engaged .
  • All feed and rotary movements are preferably carried out with the aid of a numerically controlled machine tool, so that the individual feed and rotary movements take place very quickly and very precisely.
  • the order of the feed and rotary movements is generally not important.
  • a tube in particular a stainless steel tube
  • a flexible shaft can be produced from such a tube by appropriate structuring, that is to say by introducing slots.
  • a method is particularly preferred in which the machining by Grinding takes place and, accordingly, a device is preferred in which the processing tool is a grinding tool, in particular a rotating grinding wheel, which is fed with its circumferential edge in the radial direction to the workpiece.
  • the machining tool in the form of the grinding wheel can also be rotated about an axis that runs parallel to the feed and return movement or direction. Closing the edge of a grinding wheel causes a slot in the thickness of the grinding wheel to be ground into a corresponding pipe or other elongate object.
  • the extent of the feed movement of the tool when it is fed onto the workpiece determines the depth of the slot and thus also the circumferential angle over which the slot extends if the workpiece is not additionally rotated.
  • the grinding wheel moves so far into the workpiece that there is a slot which extends over approximately 180 ° with respect to the axis of the workpiece.
  • the workpiece can then be rotated in one or both directions by an angle of, for example, 30 ° to 90 °, which results in a correspondingly larger circumferential extent of the ground slot.
  • the grinding wheel is pulled back into its starting position so that the workpiece can be advanced in order to be able to make another slot at a new axial position of the tube or generally to carry out further processing at a different axial position of the workpiece to be able to make.
  • the support device on the side opposite the processing tool and expediently at a very close axial distance from the engagement position of the tool, prevents the workpiece from evading in the lateral direction and enables precise work and manufacture of corresponding structures or slots.
  • the support device can be stationary, but optionally also adjustable, in order to be able to adapt to different workpieces and also to different processing tools, since the processing by the support device should not be obstructed or disturbed if possible. It is of course expedient if the support takes place as close as possible to the area where the machining tool also acts, in order to be able to intercept the forces occurring as well as possible and without disturbing workpiece movements.
  • the support device can also be divided and arranged at two different axial positions, close to and close to the engagement position of the machining tool.
  • the structuring of the objects with the aid of a grinding process or a grinding tool or a grinding wheel has the particular advantage that in general no post-processing of the workpiece is required anymore and that the structures on the workpiece are produced essentially without burrs, so that post-processing generally does not more are required or can have a much smaller scope than in the manufacture of the structures by milling or sawing.
  • the grinding wheel preferably has a thickness between 0.3 and 2 mm, so that accordingly there are also slots with a width between 0.3 and 2 mm.
  • the slots are preferably made with a width of approximately 1 mm and they should run essentially parallel to one another and extend in the circumferential direction of the tube over an angle of more than 180 °.
  • the repetition distance of successive (albeit offset in the circumferential direction) slots should be in the order of 1 to 5 mm, but can also be larger if the flexible shaft has a larger diameter of, for example, more than 8 or 10 mm.
  • the combination of the repetition distance of the slots and slot width ultimately determines the smallest possible bending radius of such a shaft.
  • the stability of the shaft also decreases the smaller the minimum bending radius.
  • the greatest possible circumferential extension of the slots reduces the bending stiffness, but also the stability of the shaft, so that sensible compromises are necessary.
  • the machining tool is rotatably mounted about an axis parallel to its feed movement, which means, for example in the case of a grinding wheel which is fed with its edge, that the plane of the grinding wheel is 90 ° with respect to the axis of the workpiece is inclined at different angles.
  • This angle of inclination should preferably be in the range between 60 ° and 85 °.
  • the flexible shaft mentioned above it can be used to produce slots which, in addition to their extension in the circumferential direction, also have an axial component.
  • This axial component can be selected or adjusted in relation to the intended direction of rotation of the shaft in such a way that the slots at a rotational movement of the shaft material, which may accumulate in the tube or the shaft, preferably in a direction away from the front end of the shaft.
  • the grinding wheel slightly conical in its edge region, so that the side surfaces of the slots are also slightly conical or the width of the slots increases towards the outside.
  • the shafts can be produced very quickly and efficiently with the method according to the invention and the corresponding device, they require little or no post-processing and have extremely favorable properties in use. Further advantages, features and possible uses of the present invention are clearly evident the following description of a preferred embodiment and the associated figures. Show it:
  • FIG. 1 shows a plan view of a processing device for pipes according to the invention for producing flexible shafts
  • Figure 2 is a side view of the device of Figure 1 and
  • Figure 3 shows schematically different processing stages in the manufacture of a flexible shaft from a tube with the device shown in Figures 1 and 2.
  • FIG. 1 a workpiece in the form of a tube 1, which is held with one of its ends in a clamping device 2, while the other end of the tube protrudes freely from the clamping device.
  • the clamping device is in turn mounted on a feed device 3 which is mounted on rails 13 in the direction of a Z-axis indicating the feed direction for the tool.
  • the tensioning device 2 can also be rotated with the aid of a rotation device 4, the rotation device 4 being able to set any fixed rotational positions.
  • the rotation device 4 comprises a shaft 14 which can be displaced in the direction of the Z axis, that is to say in the direction of the rotation axis, which is in turn connected to the rotatably mounted tensioning device 2.
  • the axis of the ball screw of the Z axis coincides with the axis of the tube 1 accommodated in the clamping device 2, so that the tube 1 can be rotated about its longitudinal axis, which is referred to here as the C axis.
  • FIG. 1 a processing tool in the form of a grinding wheel 7, which is attached to a corresponding grinding machine so as to be rotatable about its axis of symmetry, the grinding machine as a whole being movable in the direction of an X axis, which is at right angles to the C axis of the tube 1 runs.
  • a support device 8 in the form of a slide block is arranged opposite or slightly set back from the peripheral edge of the grinding wheel 7 and has either a bore or a partially cylindrical concave support surface for the tube 1.
  • the grinding spindle 6 can be pivoted about a pivot axis running through the center of the grinding wheel 7 and parallel to the X axis, essentially by an angle between ⁇ 30 °.
  • the mode of operation of the device according to the invention can best be seen from the various processing stages which are shown in FIG. 3 in stages a, b and c.
  • the clamping device 2 can be seen, which has one end of a ground tube 1 holds.
  • the feed device 3 has advanced the tube 1 so far that its free end protrudes somewhat beyond the support device 8 and rests with its side opposite a grinding wheel 7 in a corresponding guide surface of the support device 8.
  • the grinding wheel 7 is fed in the direction of the Z axis and radially to the C axis of the pipe 1, whereby a slot extending in the circumferential direction of the pipe is ground into the pipe wall.
  • the edge of the grinding wheel is moved so far into the tube that the slot extends at least over 180 °, possibly also about 270 ° or even more degrees with respect to the tube axis C. If necessary, even after a partially simple edge of the grinding wheel 7 in the tube 1, the tube can be rotated about the axis C by means of the rotation device 4 by a small angle of, for example, ⁇ 60 °, around the slot in the circumferential direction of the tube to expand a desired dimension. Subsequently, the grinding wheel 7 is moved back into the position recognizable in the partial picture A and the feed device 3 moves the clamping device 2 and thus also the tube 1 forward by one step, which corresponds to the repetition distance of the slots.
  • the rotation device 4 rotates the tube or before or after it by an angle which corresponds to the angular offset of successive slots. Then a slot is ground into the tube 1 again in the manner already described. This process is repeated, the tube being rotated through a predetermined angle before the next slot is made.
  • the tube for the production of the next slot is rotated through 120 °, so that there are a total of 3 different positions of the individual slots in the circumferential direction with respect to the C axis of the tube, with which three different slot groups are formed, as is the case with can be seen in the sub-images b and c, which show different stages of the manufacturing process, in stage c almost all the slots are produced which are required for the flexible shaft in question.
  • the plane of the grinding wheel can be tilted out of its position perpendicular to the C-axis of the tube 1 by a pivot axis 11 so that the slots thus produced have a corresponding inclination relative to the axis of the tube could.
  • slit profiles can be generated if necessary, which have either a constant or a varying inclination relative to the pipe axis C.

Landscapes

  • Health & Medical Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Surgery (AREA)
  • Mechanical Engineering (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Oral & Maxillofacial Surgery (AREA)
  • Molecular Biology (AREA)
  • Orthopedic Medicine & Surgery (AREA)
  • Dentistry (AREA)
  • Biomedical Technology (AREA)
  • Heart & Thoracic Surgery (AREA)
  • Medical Informatics (AREA)
  • Nuclear Medicine, Radiotherapy & Molecular Imaging (AREA)
  • Animal Behavior & Ethology (AREA)
  • General Health & Medical Sciences (AREA)
  • Public Health (AREA)
  • Veterinary Medicine (AREA)
  • Grinding Of Cylindrical And Plane Surfaces (AREA)
  • Grinding And Polishing Of Tertiary Curved Surfaces And Surfaces With Complex Shapes (AREA)

Abstract

L'invention concerne un procédé et un dispositif permettant d'usiner et de produire des pièces structurées oblongues, ainsi qu'un arbre flexible ainsi obtenu. Ledit procédé comprend les étapes suivantes: serrer une des extrémités de la pièce oblongue (1); déplacer ladite pièce dans son sens longitudinal dans une première position longitudinale prédéterminée; faire tourner la pièce autour de son axe longitudinal sans une position d'usinage voulue; approcher un outil d'usinage (7), sensiblement dans le sens radial, sur la pièce; soutenir la pièce sur sa face opposée à l'outil d'usinage; replacer l'outil dans une position de départ. L'utilisation de ce procédé permet de produire et d'usiner des pièces structurées oblongues dans le cadre d'un processus de fabrication nettement simplifié.
PCT/EP2000/012140 1999-12-15 2000-12-02 Procede et dispositif pour usiner et produire des pieces structurees oblongues et arbre flexible ainsi obtenu Ceased WO2001043915A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE1999160331 DE19960331A1 (de) 1999-12-15 1999-12-15 Verfahren und Vorrichtung zur Bearbeitung und Herstellung länglicher, strukturierter Bauteile und damit hergestellte biegsame Welle
DE19960331.6 1999-12-15

Publications (1)

Publication Number Publication Date
WO2001043915A1 true WO2001043915A1 (fr) 2001-06-21

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ID=7932655

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/EP2000/012140 Ceased WO2001043915A1 (fr) 1999-12-15 2000-12-02 Procede et dispositif pour usiner et produire des pieces structurees oblongues et arbre flexible ainsi obtenu

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DE (1) DE19960331A1 (fr)
WO (1) WO2001043915A1 (fr)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103481139A (zh) * 2013-08-21 2014-01-01 蚌埠市广瑞机械有限公司 一种自动快速打磨装置

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB1128691A (en) * 1965-04-01 1968-10-02 Bristol Aeroplane Plastics Ltd Methods of and machines for cutting slots in tubes
GB1401569A (en) * 1973-11-12 1975-07-16 Valsemey P Slitting machine
US4567795A (en) * 1984-04-30 1986-02-04 Pool James R Slot cutting apparatus
EP0445918A1 (fr) * 1990-02-07 1991-09-11 SMITH & NEPHEW DYONICS INC Instrument chirurgical coupant
WO1997003611A1 (fr) * 1995-07-18 1997-02-06 Edwards, Garland, U. Tige flexible
US5782834A (en) * 1993-01-29 1998-07-21 Smith & Nephew, Inc. Surgical instrument

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3603666A1 (de) * 1986-02-06 1987-08-13 Schmid & Wezel Verfahren und werkzeug zur herstellung des im querschnitt vieleckigen, ueber eine gewisse laenge verdrillten endes einer biegsamen welle
DE3829648A1 (de) * 1988-06-14 1989-12-21 Ravensburg Maschf Verfahren zur herstellung von nuten in zylindrischen walzen und schleifmaschine zur durchfuehrung des verfahrens
DE4208221A1 (de) * 1992-03-14 1993-09-16 Reiner Gessler Biegsame welle, vorzugsweise fuer die medizintechnik sowie verfahren zur herstellung
DE29914846U1 (de) * 1999-08-26 1999-12-16 Reiss Büromöbel GmbH, 04924 Bad Liebenwerda Biegsame Welle

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB1128691A (en) * 1965-04-01 1968-10-02 Bristol Aeroplane Plastics Ltd Methods of and machines for cutting slots in tubes
GB1401569A (en) * 1973-11-12 1975-07-16 Valsemey P Slitting machine
US4567795A (en) * 1984-04-30 1986-02-04 Pool James R Slot cutting apparatus
EP0445918A1 (fr) * 1990-02-07 1991-09-11 SMITH & NEPHEW DYONICS INC Instrument chirurgical coupant
US5782834A (en) * 1993-01-29 1998-07-21 Smith & Nephew, Inc. Surgical instrument
WO1997003611A1 (fr) * 1995-07-18 1997-02-06 Edwards, Garland, U. Tige flexible

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103481139A (zh) * 2013-08-21 2014-01-01 蚌埠市广瑞机械有限公司 一种自动快速打磨装置

Also Published As

Publication number Publication date
DE19960331A1 (de) 2001-06-21

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