Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
  • B23B—TURNING; BORING
  • B23B23/00—Tailstocks; Centres
• • 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
  • B24B1/00—Processes of grinding or polishing; Use of auxiliary equipment in connection with such processes
• • 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
  • B24B41/00—Component parts such as frames, beds, carriages, headstocks
  • B24B41/06—Work supports, e.g. adjustable steadies
  • B24B41/061—Work supports, e.g. adjustable steadies axially supporting turning workpieces, e.g. magnetically, pneumatically
  • B24B41/062—Work supports, e.g. adjustable steadies axially supporting turning workpieces, e.g. magnetically, pneumatically between centres; Dogs
• • 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
  • B24B41/00—Component parts such as frames, beds, carriages, headstocks
  • B24B41/06—Work supports, e.g. adjustable steadies
  • B24B41/065—Steady rests
• • 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
  • B24B5/02—Machines or devices designed for grinding surfaces of revolution on work, including those which also grind adjacent plane surfaces; Accessories therefor involving centres or chucks for holding work
  • B24B5/04—Machines or devices designed for grinding surfaces of revolution on work, including those which also grind adjacent plane surfaces; Accessories therefor involving centres or chucks for holding work for grinding cylindrical surfaces externally

Definitions

• the invention relates to a method and an apparatus for grinding workpieces with centers that deviate in shape.
• the prior art includes fine machining, in particular grinding, of workpieces, which are received between the tips of a workpiece headstock and a tailstock.
• fine machining in particular grinding
• workpieces that have very thin walls in the area of the clamping center are particularly difficult.
• Such workpieces are often not pre-machined to the exact shape or, due to a heat treatment applied after the pre-machining, have inaccuracies in shape such as roundness due to warpage.
• the elimination of this distortion-related out-of-roundness of thin-walled workpieces can usually not be corrected by subsequent grinding on the outside diameter of the workpieces, i.e. the out-of-roundness of the center is transferred as an error in dimensions and roundness during external cylindrical grinding.
• the tip of the tailstock which is mounted on the tailstock quill, with a pressure bolt, which is equipped with a spring element. is executed.
• the workpiece to be machined is pressed axially against the opposite tip of the workpiece spindle of the workpiece spindle stick.
• the workpiece is supported by a steady position.
• the pressure pin consists of a piston part and a rod part; the pressure pin is mounted inside the base body of the tailstock tip.
• the tailstock quill with tailstock tip can be retracted to an intermediate position.
• the workpiece for machining in the centering area of the workpiece headstock and the jaws of the support steady rest are thus centered exactly.
• FIG. 1 shows a partial top view of a grinding machine with a partial sectional view of the workpiece clamping.
• FIG. 2 shows a further partial top view of the grinding machine according to FIG. 1 with a partial sectional view of the workpiece clamping in an operating position.
• Fig. 3 shows a sectional view of the tailstock-side workpiece clamping with the tailstock tip in a contact position with the steady rest, but not shown.
• Fig. 4 shows a sectional view of the tailstock-side workpiece clamping with pressure bolts in a retracted intermediate position of the tailstock quill with the tailstock tip.
• FIG. 1 shows, for example, the clamping of a workpiece 5 on a grinding machine.
• the workpiece 5 is clamped between the tip 4 of the workpiece spindle 30 of the workpiece headstock 1 and the tip 6 with the center 11 of the tailstock 3.
• the clamping and unclamping of the workpiece between the tip 4 of the workpiece spindle 30 and the tip 6 of the quill 13 is made possible in that the tailstock quill 13 is retracted into a rear position by moving the tailstock.
• the workpiece headstock 1 and the tailstock 3 are on a grinding table 2 which can be moved in the Z direction and is only partially shown. assembled.
• the workpiece headstock 1 has a workpiece spindle 30. which is driven by a motor drive, not shown.
• the tailstock 3 is equipped with a moving tailstock quill 13 which is axially displaceable within the housing of the tailstock 3.
• the center axis of the workpiece spindle 30 of the workpiece headstock 1 and the quill 13 of the tailstock 3 are exactly aligned with one another. In between, the workpiece 5 is also clamped in alignment with its longitudinal axis.
• a support bezel 7 with movable jaws 9 is arranged on the grinding table 2.
• the grinding spindle 15 with the grinding wheel 16 is perpendicular to the workpiece in the direction of the X axis. clamping adjustable.
• the grinding spindle 15 is arranged axially parallel to the Z axis of the machine tool.
• the grinding wheel 16 is set at right angles to the workpiece in the direction of the X axis.
• the workpiece is clamped between the tip 4 of the workpiece headstock 1 and the tip 6 of the tailstock 3. Since the workpiece 5 in the center 11, which rests on the tip 6 of the tailstock 3, is very thin-walled. a centering deformation of the thin-walled area of the workpiece 5 takes place as a result of the compressive forces applied during clamping; because the tailstock-side area of the receiving center of the workpiece 5 is pressed round by the axial pressure force emanating from the tip 6 of the tailstock 3 in connection with the frustoconical tip 6 of the tailstock 3.
• a steady rest 8 is ground against which a support bezel 7 can be moved, with the grinding wheel 16 being arranged at right angles to the workpiece according to the X axis and parallel to the Z axis with the grinding wheel 16 being arranged on the grinding spindle 15 Baking 9 is started.
• the workpiece 5 is reclamped and finished in order in this way to achieve an accurate, i.e. to obtain workpiece 5 freed from non-roundness.
• FIG. 3 shows the embodiment for the frustoconical design of the tip 6, which is covered with a hard metal body 6A for reasons of wear.
• the quill 13 of the tailstock 3 is shown, the tip 6 being arranged on a guide element 24 which is aligned with the longitudinal axis of the quill 13.
• the guide element 24 has a central longitudinal bore which has bore sections which become smaller in diameter towards the end of the tip. At the opposite end of the guide element 24, the diameter water of the hole for receiving an adjustable screw 23 is the largest. The subsequent bore section has a smaller diameter.
• a spring element 22 which is adapted to this diameter is arranged in this drilling section and bears on the one hand against the end face of an adjustable screw 23 and on the other hand against the end face of a cylindrical piston part 26 of a pressure pin 21 of the same diameter.
• the other end of the cylindrical piston part 26 has an axially extending rod part 27 with a much smaller diameter.
• the rod part 27 is guided through the outlet bore of the guide element 24.
• the pressure bolt 21 preloaded with the spring element 22 exerts an axial force 32 on the workpiece 5.
• Fig. 4 the sleeve 13 of the tailstock 3 is retracted to an intermediate position according to arrow position 10, so that the cone of the tip 6 of the tailstock 3 is no longer in pressure contact with the workpiece 5, according to position 1 1A.
• the push rod 21 presses but with the spring force of the spring element 22, the workpiece 5 against the tip 4 of the workpiece spindle 30 of the workpiece headstock 1.
• the support bezel 7 ensures the radial alignment of the workpiece 5 with respect to the tip 4 of the workpiece spindle 30 and the tip 6 of the quill 13.
• the tip 6 of the tailstock 3 can thus be retracted to an intermediate position 10 without the centering achieved during clamping To affect workpiece 5. In any case, this path must be so great that the workpiece 5 no longer contacts the tip 6 of the sleeve 13, so that the workpiece 5 receives a contact-free center 11A. It is therefore sufficient if the travel distance to this intermediate position is only a few tenths of a millimeter.
• the workpiece 5 Since the torque of the rotary movement of the workpiece 5 is transmitted through the tip 4 of the workpiece headstock 1, the workpiece 5 must be pressed against the tip 4 of the workpiece spindle 30 by a force 32. This frictional connection is provided by the pressure pin 21 via the rod part 27. In this way, the workpiece 5 is rotatably driven and held in the centered position by the support lugs 7, so that complete machining of the workpiece 5 on the outer circumference is made possible. In this way, the outer circumference of the tailstock end of the workpiece 5 can also be machined without inaccuracies, ie out-of-roundness, being transmitted to the workpiece 5.
• At least one machining step on another machine tool with a different clamping system can be saved, whereby the machining costs can be reduced.
• the method according to the invention and the device developed for this purpose are in no way limited to the grinding of workpieces; rather, other finishing operations can also be carried out afterwards.

Priority Applications (6)

Applications Claiming Priority (2)

Publications (1)

Family

ID=7890850

Family Applications (1)

Country Status (11)

Cited By (8)

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Citations (2)

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• 1998
  • 1998-12-11 DE DE19857359A patent/DE19857359B4/de not_active Expired - Lifetime
• 1999
  • 1999-12-09 JP JP2000587916A patent/JP2002532263A/ja active Pending
  • 1999-12-09 KR KR1020017007035A patent/KR20010093805A/ko not_active Application Discontinuation
  • 1999-12-09 EP EP99963457A patent/EP1137505A1/de not_active Withdrawn
  • 1999-12-09 AU AU19747/00A patent/AU1974700A/en not_active Abandoned
  • 1999-12-09 CZ CZ20012055A patent/CZ296983B6/cs not_active IP Right Cessation
  • 1999-12-09 CN CN99813931A patent/CN1329528A/zh active Pending
  • 1999-12-09 WO PCT/EP1999/009702 patent/WO2000035617A1/de active IP Right Grant
  • 1999-12-09 CA CA002352426A patent/CA2352426A1/en not_active Abandoned
  • 1999-12-09 BR BR9916125-7A patent/BR9916125A/pt not_active IP Right Cessation
  • 1999-12-09 RU RU2001118829/02A patent/RU2001118829A/ru not_active Application Discontinuation

Patent Citations (2)

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