WO1997022428A1 - Method for machining workpieces in a lathe and control unit for said lathe - Google Patents

Method for machining workpieces in a lathe and control unit for said lathe Download PDF

Info

Publication number
WO1997022428A1
WO1997022428A1 PCT/NL1996/000484 NL9600484W WO9722428A1 WO 1997022428 A1 WO1997022428 A1 WO 1997022428A1 NL 9600484 W NL9600484 W NL 9600484W WO 9722428 A1 WO9722428 A1 WO 9722428A1
Authority
WO
WIPO (PCT)
Prior art keywords
spindle
workpieces
lathe
machining
tool
Prior art date
Application number
PCT/NL1996/000484
Other languages
French (fr)
Inventor
Hubert Rudolf Josef Vreuls
Original Assignee
Holding H. Vreuls B.V.
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 Holding H. Vreuls B.V. filed Critical Holding H. Vreuls B.V.
Priority to AU10422/97A priority Critical patent/AU1042297A/en
Publication of WO1997022428A1 publication Critical patent/WO1997022428A1/en

Links

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
    • B23Q—DETAILS, COMPONENTS, OR ACCESSORIES FOR MACHINE TOOLS, e.g. ARRANGEMENTS FOR COPYING OR CONTROLLING; MACHINE TOOLS IN GENERAL CHARACTERISED BY THE CONSTRUCTION OF PARTICULAR DETAILS OR COMPONENTS; COMBINATIONS OR ASSOCIATIONS OF METAL-WORKING MACHINES, NOT DIRECTED TO A PARTICULAR RESULT
    • B23Q39/00—Metal-working machines incorporating a plurality of sub-assemblies, each capable of performing a metal-working operation
    • B23Q39/04—Metal-working machines incorporating a plurality of sub-assemblies, each capable of performing a metal-working operation the sub-assemblies being arranged to operate simultaneously at different stations, e.g. with an annular work-table moved in steps
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
    • B23B—TURNING; BORING
    • B23B3/00—General-purpose turning-machines or devices, e.g. centre lathes with feed rod and lead screw; Sets of turning-machines
    • B23B3/30—Turning-machines with two or more working-spindles, e.g. in fixed arrangement
    • B23B3/32—Turning-machines with two or more working-spindles, e.g. in fixed arrangement for performing identical operations simultaneously on two or more workpieces

Definitions

  • the present invention concerns a method for the machining of workpieces in a lathe, which lathe comprises two spindles, the centre lines of which lie in each other's extensions and which are each provided on faces directed towards each other with a chuck for the clamping of a workpiece, of which spindles at least one can be displaced in the direction of said centre lines relative to the other spindle, and a tool- holder, displaceable in the directions perpendicular to and parallel to said centre lines between said spindles, for at least one toolpiece for the machining of a workpiece clamped in one of the chucks, involving the step of (1) the clamping of a first workpiece in the chuck of one of the two spindles .
  • twin-spindle system Such a method is followed for the machining of workpieces in a lathe with a twin-spindle system, which is equipped for the execution of a rearward machining of a workpiece.
  • the twin-spindle system comprises two independently driven spindles which are each provided with a chuck for the clamping and take-over respectively of a workpiece, whereby the centre lines of the spindles lie in each other's extensions.
  • the position of a first spindle, the main spindle is fixed relative to the lathe bed, and the second spindle, the sub-spindle can be displaced relative to the main spindle along the said centre lines.
  • a tool-holder usually a turret with several toolpieces, which can be displaced in the direction perpendicular to and parallel to said centre lines, for the machining of a workpiece clamped in one of the chucks .
  • the front face of a workpiece which is clamped in one of the chucks is machined by one or a sequence of several of the toolpieces on the turret, after which the turret is withdrawn in a direction perpendicular to the centre lines of the spindles.
  • the sub-spindle which has meanwhile obtained the same rotation speed as the main spindle under the control of the control unit, is moved with open chuck towards the main spindle, after which the rotating chuck of the sub-spindle is clamped onto the workpiece which is clamped in the chuck of the main spindle and rotating with it.
  • the workpiece is released by the chuck of the main spindle, and the rotating subspindle with workpiece is moved in the opposite direction, to a position sufficiently far from the main spindle, and the turret is placed back between the main and sub-spindle, after which the rear face of the workpiece, now clamped in the chuck of the sub-spindle is machined by one or a sequence of several of the toolpieces on the turret .
  • the aim of the invention is to provide a method for the machining of workpieces in a lathe with a twin-spindle system, according to which the production capacity of the lathe can be enhanced in a simple and cost-saving way.
  • the aim of the invention is also to provide a control unit for a lathe with a twin-spindle system, with the aid of which the intended cost-saving and capacity enhancing method can be carried out in such a lathe.
  • a method of the type named at the beginning is characterised according to the invention by the steps of (2) the clamping of a second workpiece, identical to the first one, into the chuck of the other of the two spindles, in such a way that the faces of the workpieces to be machined are directed towards one another,
  • a method according to the invention includes for example the step of:
  • a method according to the invention for the machining of workpieces in a lathe whereby a first spindle is rigidly fixed in the direction of its centre line and a second spindle can move in the direction of its centre line, contains the step of
  • a method for the machining of workpieces in a lathe, where a first spindle is fixed rigidly in the direction of its centre line and a second spindle can be displaced along its centre line comprises, according to the invention, the step of
  • the invention also concerns a control unit for a lathe, which lathe comprises two spindles, the centre lines of which lie in each other's extensions, and which are each provided on faces directed towards each other with a chuck for the clamping of a workpiece, of which spindles at least one can be displaced in the direction of said centre lines relative to the other spindle, and a tool-holder which can be displaced in the directions perpendicular to and parallel to said centre lines between said spindles, for at least one toolpiece for the machining of a workpiece clamped in one of the chucks .
  • Such a control unit is applied for the control of lathes with a twin-spindle system arranged for the execution of a rear face machining of a workpiece .
  • a control unit for a lathe of the type stated above contains according to the invention means for the effecting of a simultaneous displacement of at least one of the displaceable spindles intended for a simultaneous machining of two identical workpieces clamped in the chucks and the tool-holder relative to the other spindle.
  • control unit comprises means for the effecting of a displacement of the second spindle and the tool-holder from an arbitrary position to an initial position in which two identical clamped workpieces have symmetrical positions relative to a toolpiece for the machining of these workpieces .
  • control unit for a lathe of which a first spindle is rigidly fixed in the direction of its centre line, and a second spindle can be displaced in the direction of its centre line, comprises in accordance with the invention means for the effecting of a simultaneous displacement of the second spindle and the tool-holder from the initial position to a working position in which the workpieces are in contact with the respective toolpiece for the machining of these workpieces, whereby the instantaneous speed of the second spindle during the displacement is twice the instantaneous speed of the tool-holder during the displacement in a direction parallel to the centre lines .
  • this unit contains means for the effecting of a simultaneous displacement of the second spindle and the tool-holder during the simultaneous machining of two identical workpieces clamped in the chucks, whereby the instantaneous speed of the second spindle during the displacement thereof is twice the instantaneous speed of the tool-holder during the displacement thereof in a direction parallel to the centre line, and the rotational speed of the two spindles is the same .
  • the control unit may, according to the invention, comprise an electronic control unit, but has in preference a numerically controlled regulation unit, so that a lathe controlled by it can be operated in a simple and rapid manner.
  • la shows a part of a much simplified longitudinal section of a lathe with a twin-spindle system, with a first rigidly fixed spindle 1 (the main spindle) and a second spindle 2 which can be displaced in a longitudinal direction (the sub-spindle) , the centre lines 3 of which lie in each other's extensions.
  • a tool-holder 4 which can be rotated around an axis parallel to the centre lines 3, there is clamped a first lathe tool 5.
  • the tool-holder 4 can be moved by means of a carriage 7 in a direction parallel with the centre line 3, the Z- direction, and along a cross slide 8 moveable in a direction X perpendicular to the Z-direction and attached to the carriage 7.
  • FIG. la shows an initial situation, whereby an unmachined workpiece 11 is clamped in a first chuck 9 of the main spindle 1, and where a second chuck 10 of the sub- spindle 2 is empty.
  • Fig. lb shows how under the control of a control unit, not ⁇ T , the carriage 7 has been moved in the Z-direction and t tool-holder 4 has been moved in the X-direction, so that tne lathe tool 5 is brought into contact with the workpiece 11, where the main spindle 1 with chuck 9 and workpiece 11 comes into rotation.
  • Fig. lc shows a situation after the machining of a first face of the workpiece 11, where the carriage 7 with tool- holder 4 has returned to the initial situation.
  • Fig. Id shows the situation in which the sub-spindle 2 has been moved in the Z-direction towards the mains spindle 1, and the chuck 10 of the sub-spindle 2 is clamped around the workpiece 11, which can then be released by the chuck 9 of main spindle 1.
  • Fig. le shows an initial situation in which the system is ready for a rear face machining of the workpiece 11, which is now clamped in chuck 10 of sub-spindle 2.
  • a second lathe tool 6 suitable for this machining action clamped in the tool-holder 4 is brought to such a position that by a backward motion of the carriage 7 in the Z-direction and the movement of the tool-holder 4 in the X- direction, it can be brought in contact with the side to be machined of the workpiece 11 clamped in the chuck 10. It can be seen from figures la - le that in the machining of workpieces in a lathe with a twin-spindle system one of the chucks 9, 10 is empty (with the exception of the moment shown in fig. Id, at which the workpiece 11 is taken over by the second chuck 10 from the first chuck 9) .
  • FIG. 2a shows a part of a much simplified longitudinal section of a lathe with a twin-spindle system, analogous to fig. la. Corresponding parts in the figs, la-le are indicated by the same numbers.
  • Fig. 2a shows an initial situation, where an unmachined workpiece 11 is clamped in the chuck 9 of the main spindle 1, and where a second workpiece 11' , which is identical with the first workpiece 11, is clamped in the chuck 10 of the sub-spindle 2, where the faces of the workpieces 11 and 11 ' to be machined are directed to each other. In the tool-holder two identical lathe tools 5, 5' are clamped. In the initial situation shown the installed workpieces 11, 11' have symmetrical positions relative to the respective lathe tools 5, 5' .
  • Fig. 2b shows a situation in which the clamped identical workpieces 11, 11' are machined simultaneously, whereby the control unit (not shown) of the lathe keeps the rotational speeds of the main spindle 1 and the sub-spindle 2 equal to each other at all times, and whereby the rate of displacement of the sub-spindle 2 is at any time kept twice as great as the rate of displacement of the carriage 7.
  • Fig. 2c shows a subsequent initial situation, where the identical workpieces 11, 11' machined in identical manners according to fig.
  • a workpiece is clamped in each of the chucks 9,10, which workpieces can be machined simultaneously under the control of a control unit set up for this purpose.
  • the production capacity can in principle be increased by a factor of two relative to the production capacity of such a lathe when provided with a known type of control unit.
  • the method and the control unit are applied in a lathe with a rigidly fixed main spindle and a moveable sub-spindle.
  • the invention is however in no way limited to this type of preferred embodiment .
  • a method and a control unit according to the invention are applicable to any lathe with a twin-spindle system in which a relative displacement of the spindles and the tool- holder relative to each other in the direction of the centre line of the spindles can be effected, thus for instance also in a lathe in which the tool-holder is rigidly fixed in the direction parallel to the centre lines of the spindles, and both spindles can be displaced relative to the tool-holder.

Abstract

Method and apparatus for the machining of workpieces in a lathe, which lathe comprises two spindles, the centre lines of which lie in each other's extensions and which are each, on mutually opposed faces, provided with a chuck for the clamping of a workpiece, of which spindles at least one can be displaced in the direction of the centre lines relative to the other spindle, and a tool-holder, which can be displaced in the directions perpendicular to and parallel to said centre lines, for at least one toolpiece for the machining of a workpiece clamped into one of the chucks, which method comprises the steps of (1) the clamping of a first workpiece in the chuck of one of the two spindles, (2) the clamping of a second workpiece, identical to the first, in the chuck of the other of the two spindles, in such a way that the faces of the workpieces to be machined are directed towards one another, (3) the provision of a respective toolpiece in the tool-holder for the machining of the first and the second workpiece, and (4) the effecting of a suitable simultaneous displacement of the at least one moveable spindle and the tool-holder relative to the other spindle for the execution of a simultaneous machining of two identical workpieces clamped in the chucks.

Description

METHOD FOR MACHINING WORKPIECES IN A LATHE AND CONTROL UNIT FOR SAID LATHE
The present invention concerns a method for the machining of workpieces in a lathe, which lathe comprises two spindles, the centre lines of which lie in each other's extensions and which are each provided on faces directed towards each other with a chuck for the clamping of a workpiece, of which spindles at least one can be displaced in the direction of said centre lines relative to the other spindle, and a tool- holder, displaceable in the directions perpendicular to and parallel to said centre lines between said spindles, for at least one toolpiece for the machining of a workpiece clamped in one of the chucks, involving the step of (1) the clamping of a first workpiece in the chuck of one of the two spindles . Such a method is followed for the machining of workpieces in a lathe with a twin-spindle system, which is equipped for the execution of a rearward machining of a workpiece. The twin-spindle system comprises two independently driven spindles which are each provided with a chuck for the clamping and take-over respectively of a workpiece, whereby the centre lines of the spindles lie in each other's extensions. In this case the position of a first spindle, the main spindle, is fixed relative to the lathe bed, and the second spindle, the sub-spindle can be displaced relative to the main spindle along the said centre lines. Between the main and sub-spindles there is a tool-holder, usually a turret with several toolpieces, which can be displaced in the direction perpendicular to and parallel to said centre lines, for the machining of a workpiece clamped in one of the chucks . Under the control of a known type of control unit in a lathe with twin-spindle system, the front face of a workpiece which is clamped in one of the chucks, usually that of the main spindle, is machined by one or a sequence of several of the toolpieces on the turret, after which the turret is withdrawn in a direction perpendicular to the centre lines of the spindles. After this the sub-spindle, which has meanwhile obtained the same rotation speed as the main spindle under the control of the control unit, is moved with open chuck towards the main spindle, after which the rotating chuck of the sub-spindle is clamped onto the workpiece which is clamped in the chuck of the main spindle and rotating with it. Then the workpiece is released by the chuck of the main spindle, and the rotating subspindle with workpiece is moved in the opposite direction, to a position sufficiently far from the main spindle, and the turret is placed back between the main and sub-spindle, after which the rear face of the workpiece, now clamped in the chuck of the sub-spindle is machined by one or a sequence of several of the toolpieces on the turret .
During the machining of a workpiece in the known type of lathe with a twin-spindle system the workpiece is clamped in turn in the chuck of one of the spindles, and the chuck of the other spindle is empty, with the exception of the moment when the workpiece is taken over by the chuck. Since for the most part a workpiece is clamped in only one of the two chucks, in fact only half of the production capacity of the lathe is used. The aim of the invention is to provide a method for the machining of workpieces in a lathe with a twin-spindle system, according to which the production capacity of the lathe can be enhanced in a simple and cost-saving way.
The aim of the invention is also to provide a control unit for a lathe with a twin-spindle system, with the aid of which the intended cost-saving and capacity enhancing method can be carried out in such a lathe.
A method of the type named at the beginning is characterised according to the invention by the steps of (2) the clamping of a second workpiece, identical to the first one, into the chuck of the other of the two spindles, in such a way that the faces of the workpieces to be machined are directed towards one another,
(3) the provision of an appropriate toolpiece in the tool-holder respectively for the machining of the first and the second workpiece, and
(4) the effecting of a suitable simultaneous displacement of the at least one displaceable spindle and the tool-holder relative to the other spindle, for the execution of a simultaneous machining of two identical workpieces clamped in the chucks.
By effecting a simultaneous suitable displacement of a spindle and the tool-holder relative to the other spindle, i.e. a displacement in such a way that a respective toolpiece clamped in the tool-holder for the machining of the workpieces clamped in the chucks makes simultaneous contact with the workpieces, whereby the relative speed of these workpieces relative to the respective toolpiece is of the same magnitude and opposite sense, it appears in a surprising manner possible to carry out a simultaneous machining of two workpieces in a lathe with a twin-spindle system.
A method according to the invention includes for example the step of:
(5) the effecting of a displacement of the second spindle and the tool-holder from an arbitrary position to an initial position in which two identical clamped workpieces take up symmetrical positions relative to a toolpiece for the machining of these workpieces .
In preference a method according to the invention for the machining of workpieces in a lathe, whereby a first spindle is rigidly fixed in the direction of its centre line and a second spindle can move in the direction of its centre line, contains the step of
(6) the effecting of a simultaneous displacement of the second spindle and the tool-holder from an initial position in which the two clamped workpieces take up symmetrical positions relative to the toolpiece for the machining of these workpieces, to a working position in which the workpieces are in contact with the respective toolpiece for the machining of these workpieces, whereby the instantaneous speed of the second spindle during the displacement is twice the instantaneous speed of the tool-holder during the displacement in a direction parallel to the centre lines.
In preference during the last displacement the rotational speed of the first and second spindle are the same, so that the simultaneous machining of the workpieces following the displacement can be carried out immediately.
A method for the machining of workpieces in a lathe, where a first spindle is fixed rigidly in the direction of its centre line and a second spindle can be displaced along its centre line comprises, according to the invention, the step of
(8) the effecting of a simultaneous displacement of the second spindle and the tool-holder during the simultaneous machining of the two clamped workpieces, whereby the instantaneous speed of the second spindle during its displacement is twice the instantaneous speed of the tool- holder during its displacement in a direction parallel to the centre lines, and the rotational speed of the two spindles is the same.
As a result of the effecting of this simultaneous displacement in such a lathe, during the machining of the workpieces the instantaneous relative displacement of the workpiece in the chuck of the first spindle relative to the tool-holder is of the same magnitude as and in the opposite sense to the instantaneous relative displacement of the workpiece in the chuck of the second spindle relative to the tool-holder, so that the toolpiece appropriate to the machining of the workpieces acts simultaneously on the workpieces, under completely identical conditions for both workpieces, so that the workpieces remain completely identical to each other during the machining.
The invention also concerns a control unit for a lathe, which lathe comprises two spindles, the centre lines of which lie in each other's extensions, and which are each provided on faces directed towards each other with a chuck for the clamping of a workpiece, of which spindles at least one can be displaced in the direction of said centre lines relative to the other spindle, and a tool-holder which can be displaced in the directions perpendicular to and parallel to said centre lines between said spindles, for at least one toolpiece for the machining of a workpiece clamped in one of the chucks .
Such a control unit is applied for the control of lathes with a twin-spindle system arranged for the execution of a rear face machining of a workpiece .
A control unit for a lathe of the type stated above contains according to the invention means for the effecting of a simultaneous displacement of at least one of the displaceable spindles intended for a simultaneous machining of two identical workpieces clamped in the chucks and the tool-holder relative to the other spindle.
With the aid of such a control unit it appears possible to carry out simultaneous machining of two workpieces according to the invention in a lathe with a twin-spindle system.
In an embodiment, the control unit comprises means for the effecting of a displacement of the second spindle and the tool-holder from an arbitrary position to an initial position in which two identical clamped workpieces have symmetrical positions relative to a toolpiece for the machining of these workpieces .
In a further embodiment the control unit for a lathe, of which a first spindle is rigidly fixed in the direction of its centre line, and a second spindle can be displaced in the direction of its centre line, comprises in accordance with the invention means for the effecting of a simultaneous displacement of the second spindle and the tool-holder from the initial position to a working position in which the workpieces are in contact with the respective toolpiece for the machining of these workpieces, whereby the instantaneous speed of the second spindle during the displacement is twice the instantaneous speed of the tool-holder during the displacement in a direction parallel to the centre lines . In a preferred embodiment of a control unit according to the invention for a lathe of which a first spindle is fixed rigidly in the direction of its centre line and a second spindle can be displaced in the direction of its centre line, this unit contains means for the effecting of a simultaneous displacement of the second spindle and the tool-holder during the simultaneous machining of two identical workpieces clamped in the chucks, whereby the instantaneous speed of the second spindle during the displacement thereof is twice the instantaneous speed of the tool-holder during the displacement thereof in a direction parallel to the centre line, and the rotational speed of the two spindles is the same .
The control unit may, according to the invention, comprise an electronic control unit, but has in preference a numerically controlled regulation unit, so that a lathe controlled by it can be operated in a simple and rapid manner.
The invention will be explained further through an example of an embodiment, with reference to the attached drawing.
In the drawing figures la - le show, in a schematic longitudinal section of a lathe with a twin-spindle system, a number of steps for the machining of workpieces in the lathe according to the prior art, and figures 2a-2c show, in a schematic longitudinal section of a lathe with a twin-spindle system, a number of steps for the machining of workpieces in the lathe according to the invention. Fig. la shows a part of a much simplified longitudinal section of a lathe with a twin-spindle system, with a first rigidly fixed spindle 1 (the main spindle) and a second spindle 2 which can be displaced in a longitudinal direction (the sub-spindle) , the centre lines 3 of which lie in each other's extensions. In a tool-holder 4, which can be rotated around an axis parallel to the centre lines 3, there is clamped a first lathe tool 5. The tool-holder 4 can be moved by means of a carriage 7 in a direction parallel with the centre line 3, the Z- direction, and along a cross slide 8 moveable in a direction X perpendicular to the Z-direction and attached to the carriage 7. A chuck 9 is attached to the main spindle 1. Fig. la shows an initial situation, whereby an unmachined workpiece 11 is clamped in a first chuck 9 of the main spindle 1, and where a second chuck 10 of the sub- spindle 2 is empty.
Fig. lb shows how under the control of a control unit, not ε T , the carriage 7 has been moved in the Z-direction and t tool-holder 4 has been moved in the X-direction, so that tne lathe tool 5 is brought into contact with the workpiece 11, where the main spindle 1 with chuck 9 and workpiece 11 comes into rotation.
Fig. lc shows a situation after the machining of a first face of the workpiece 11, where the carriage 7 with tool- holder 4 has returned to the initial situation.. Fig. Id shows the situation in which the sub-spindle 2 has been moved in the Z-direction towards the mains spindle 1, and the chuck 10 of the sub-spindle 2 is clamped around the workpiece 11, which can then be released by the chuck 9 of main spindle 1. Fig. le shows an initial situation in which the system is ready for a rear face machining of the workpiece 11, which is now clamped in chuck 10 of sub-spindle 2. For this purpose after the rotation of the tool-holder 4 through a certain angle, a second lathe tool 6 suitable for this machining action clamped in the tool-holder 4 is brought to such a position that by a backward motion of the carriage 7 in the Z-direction and the movement of the tool-holder 4 in the X- direction, it can be brought in contact with the side to be machined of the workpiece 11 clamped in the chuck 10. It can be seen from figures la - le that in the machining of workpieces in a lathe with a twin-spindle system one of the chucks 9, 10 is empty (with the exception of the moment shown in fig. Id, at which the workpiece 11 is taken over by the second chuck 10 from the first chuck 9) . Fig. 2a shows a part of a much simplified longitudinal section of a lathe with a twin-spindle system, analogous to fig. la. Corresponding parts in the figs, la-le are indicated by the same numbers. Fig. 2a shows an initial situation, where an unmachined workpiece 11 is clamped in the chuck 9 of the main spindle 1, and where a second workpiece 11' , which is identical with the first workpiece 11, is clamped in the chuck 10 of the sub-spindle 2, where the faces of the workpieces 11 and 11 ' to be machined are directed to each other. In the tool-holder two identical lathe tools 5, 5' are clamped. In the initial situation shown the installed workpieces 11, 11' have symmetrical positions relative to the respective lathe tools 5, 5' .
Fig. 2b shows a situation in which the clamped identical workpieces 11, 11' are machined simultaneously, whereby the control unit (not shown) of the lathe keeps the rotational speeds of the main spindle 1 and the sub-spindle 2 equal to each other at all times, and whereby the rate of displacement of the sub-spindle 2 is at any time kept twice as great as the rate of displacement of the carriage 7. Fig. 2c shows a subsequent initial situation, where the identical workpieces 11, 11' machined in identical manners according to fig. 2b remain clamped, and whereby after the rotation of the tool-holder 4 through a certain angle, subsequent identical lathe tools 13, 13' suitable for a next identical machining, and clamped in the tool-holder 4, are brought into such a position that the workpieces 11, 11' again have a symmetrical position relative to these lathe tools 13, 13' (or other toolpieces) , after which a machining action according to the method described for fig. 2b can be carried out again.
As may be seen from figs. 2a-2c, during machining of workpieces in a lathe with twin-spindle system according to the invention, a workpiece is clamped in each of the chucks 9,10, which workpieces can be machined simultaneously under the control of a control unit set up for this purpose. In a lathe with twin-spindle system provided with a control unit according to the invention, the production capacity can in principle be increased by a factor of two relative to the production capacity of such a lathe when provided with a known type of control unit.
In the preferred embodiment described above the method and the control unit are applied in a lathe with a rigidly fixed main spindle and a moveable sub-spindle. The invention is however in no way limited to this type of preferred embodiment .
A method and a control unit according to the invention are applicable to any lathe with a twin-spindle system in which a relative displacement of the spindles and the tool- holder relative to each other in the direction of the centre line of the spindles can be effected, thus for instance also in a lathe in which the tool-holder is rigidly fixed in the direction parallel to the centre lines of the spindles, and both spindles can be displaced relative to the tool-holder.

Claims

1. Method for the machining of workpieces in a lathe, which lathe comprises two spindles, the centre lines of which lie in each other's extensions and which are each provided on faces directed towards each other with a chuck for the clamping of a workpiece, of which spindles at least one can be displaced in the direction of said centre lines relative to the other spindle, and a tool-holder, displaceable in the directions perpendicular to and parallel to said centre lines between said spindles, for at least one toolpiece for the machining of a workpiece clamped in one of the chucks, involving the step of
(1) the clamping of a first workpiece in the chuck of one of the two spindles , characterised by the steps of
(2) the clamping of a second workpiece, identical to the first one, into the chuck of the other of the two spindles, in such a way that the faces of the workpieces to be machined are directed towards one another,
(3) the provision of an appropriate toolpiece in the tool-holder respectively for the machining of the first and the second workpiece, and
(4) the effecting of a suitable simultaneous displacement of the at least one displaceable spindle and the tool-holder relative to the other spindle, for the execution of a simultaneous machining of two identical workpieces clamped in the chucks.
2. Method according to claim 1, characterised bv the step of
(5) the effecting of a displacement of the at least one displaceable spindle and the tool-holder from an arbitrary position to an initial position in which two identical clamped workpieces take up symmetrical positions relative to a toolpiece for the machining of the workpieces .
3. Method according to claim 1 or 2 for the machining of workpieces in a lathe, whereby a first spindle is rigidly fixed in the direction of its centre line and a second spindle can be displaced in the direction of its centre line, characterised by the step of (6) the effecting of a simultaneous displacement of the second spindle and the tool-holder from an initial position in which the two clamped workpieces take up symmetrical positions relative to the toolpiece for the machining of these workpieces, to a working position in which the workpieces are in contact with the respective toolpiece for the machining of the workpieces, whereby the instantaneous speed of the second spindle during the displacement is twice the instantaneous speed of the tool-holder during the displacement in a direction parallel to the centre lines .
4. Method according to claim 3, characterised by the step of
(7) effecting, during the displacement of the second spindle and the tool-holder from the initial position to the working position, of a rotation of the first and second spindle with the same rotational speed.
5. Method according to one of the claims 1-4 for the machining of workpieces in a lathe, whereby a first spindle is rigidly fixed in the direction of its centre line and a second spindle can be displaced in the direction of its centre line, characterised by the step of
(8) the effecting of a simultaneous displacement of the second spindle and the tool-holder during the simultaneous machining of the two clamped workpieces, whereby the instantaneous speed of the second spindle during its displacement is twice the instantaneous speed of the tool- holder during its displacement in a direction parallel to the centre lines, and the rotational speed of the two spindles is the same.
6. Control unit for a lathe, which lathe comprises two spindles, the centre lines of which lie in each other's extensions and which are each provided on faces directed towards each other with a chuck for the clamping of a workpiece, of which spindles at least one can be displaced in the direction of said centre lines relative to the other spindle, and a tool-holder, displaceable in the directions perpendicular to and parallel to said centre lines between said spindles, for at least one toolpiece for the machining of a workpiece clamped in one of the chucks, characterised in that the control unit comprises means for the execution of step (4) of the method according to claim 1.
7. Control unit according to claim 6, characterised by means for the execution of step (5) of the method according to claim 2.
8. Control unit according to one of the claims 6 or 7 for a lathe of which a first spindle is rigidly fixed in the direction of its centre line spindle and a second spindle can be displaced in the direction of its centre line, characterised in that it comprises means for the execution of step (6) of the method according to claim 3.
9. Control unit according to claim 8, characterised by means for the execution of step (7) of the method according to claim 4.
10. Control unit according to one of the claims 6 - 9 for a lathe of which a first spindle is rigidly fixed in the direction of its centre line and a second spindle can be displaced in the direction of its centre line, characterised in that it comprises means for the execution of step (8) of the method according to claim 5.
11. Control unit containing means according to one of the claims 6 - 10, characterised in that it comprises a numerically controlled regulation unit.
12. Lathe provided with a control unit according to one of the claims 6 - 11.
PCT/NL1996/000484 1995-12-18 1996-12-11 Method for machining workpieces in a lathe and control unit for said lathe WO1997022428A1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AU10422/97A AU1042297A (en) 1995-12-18 1996-12-11 Method for machining workpieces in a lathe and control unit for said lathe

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
NL1001918 1995-12-18
NL1001918A NL1001918C2 (en) 1995-12-18 1995-12-18 Method for machining workpieces in a lathe and control device therefor.

Publications (1)

Publication Number Publication Date
WO1997022428A1 true WO1997022428A1 (en) 1997-06-26

Family

ID=19762049

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/NL1996/000484 WO1997022428A1 (en) 1995-12-18 1996-12-11 Method for machining workpieces in a lathe and control unit for said lathe

Country Status (4)

Country Link
AU (1) AU1042297A (en)
NL (1) NL1001918C2 (en)
TW (1) TW289743B (en)
WO (1) WO1997022428A1 (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102189273A (en) * 2011-04-22 2011-09-21 淮阴工学院 Machine tool special for double-sided turning

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2178991A (en) * 1985-08-13 1987-02-25 Ti Machine Tools Ltd Machine tool having two spindles
US4719676A (en) * 1984-09-10 1988-01-19 Wadell Equipment Company, Inc. Flexible machining system
DE3842190A1 (en) * 1988-12-15 1990-06-21 Heyligenstaedt Gmbh & Co Kg Lathe
DE4430113A1 (en) * 1994-08-25 1996-02-29 Berliner Werkzeugmasch Tool machine for rotationally symmetrical work pieces

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4719676A (en) * 1984-09-10 1988-01-19 Wadell Equipment Company, Inc. Flexible machining system
GB2178991A (en) * 1985-08-13 1987-02-25 Ti Machine Tools Ltd Machine tool having two spindles
DE3842190A1 (en) * 1988-12-15 1990-06-21 Heyligenstaedt Gmbh & Co Kg Lathe
DE4430113A1 (en) * 1994-08-25 1996-02-29 Berliner Werkzeugmasch Tool machine for rotationally symmetrical work pieces

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102189273A (en) * 2011-04-22 2011-09-21 淮阴工学院 Machine tool special for double-sided turning

Also Published As

Publication number Publication date
NL1001918C2 (en) 1997-06-19
TW289743B (en) 1996-11-01
AU1042297A (en) 1997-07-14

Similar Documents

Publication Publication Date Title
US5152201A (en) Headstock-reciprocating-type automatic lathe and machining method using the same
EP0215208B1 (en) Machine tool
US4457193A (en) Machine-tool comprising two opposed coaxial spindles
EP0208125B1 (en) Automatic tool exchange system for machine tools
US5486151A (en) Machining center for machining a workpiece by means of at least two interchangeable tools
GB2178991A (en) Machine tool having two spindles
EP0226836A1 (en) Numerical control machine
EP0335659A3 (en) A setting control method of machining coordinate system in a machine tool
WO1999011408A1 (en) Automatic lathe and method of controlling same
JP3316003B2 (en) Numerically controlled automatic lathe and machining method with numerically controlled automatic lathe
US5210917A (en) Multiple station machine for bar machining
JP2561577Y2 (en) Opposing spindle lathe with tailstock holder
WO1997022428A1 (en) Method for machining workpieces in a lathe and control unit for said lathe
US6024001A (en) Method of turning works and lathe for carrying out the method
US5207135A (en) Multispindle lathe and method for machining workpieces
EP0215315B1 (en) Suspension for vehicles
JPS5771704A (en) Lathe
GB2262061A (en) Double spindle type lathe
JP2678838B2 (en) Combined processing NC lathe
JPH0542401A (en) Nc machine tool
JP2807823B2 (en) Work machining equipment for 2-spindle opposed CNC lathe
JPH08126901A (en) Opposed spindle lathe
JPH0335903A (en) Numerically controlled compound lathe and work method of same
JP2782290B2 (en) Multi-tasking machine with automatic tool changer
US3587368A (en) Turret lathe or like machine

Legal Events

Date Code Title Description
AK Designated states

Kind code of ref document: A1

Designated state(s): AL AM AT AU AZ BA BB BG BR BY CA CH CN CU CZ DE DK EE ES FI GB GE HU IL IS JP KE KG KP KR KZ LC LK LR LS LT LU LV MD MG MK MN MW MX NO NZ PL PT RO RU SD SE SG SI SK TJ TM TR TT UA UG US UZ VN AM AZ BY KG KZ MD RU TJ TM

AL Designated countries for regional patents

Kind code of ref document: A1

Designated state(s): KE LS MW SD SZ UG AT BE CH DE DK ES FI FR GB GR IE IT LU MC NL PT SE BF BJ CF CG

DFPE Request for preliminary examination filed prior to expiration of 19th month from priority date (pct application filed before 20040101)
121 Ep: the epo has been informed by wipo that ep was designated in this application
NENP Non-entry into the national phase

Ref country code: JP

Ref document number: 97522671

Format of ref document f/p: F

REG Reference to national code

Ref country code: DE

Ref legal event code: 8642

122 Ep: pct application non-entry in european phase