JP2007061937A - Two-spindle three-turret lathe - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a lathe which has two spindles opposed to each other on the same axis, and three turret tool posts across the axes, and carries out flat machining of a circumferential surface of a workpiece, wherein the lathe achieves machining of the workpiece with a complicated shape including machining of parallel flat surfaces of the circumferential surface of the workpiece and boring of parallel holes formed in the same. <P>SOLUTION: All the three turrets each have mounted thereon a drive unit for a rotary tool including a drill and an end mill, and an NC-controlled Y-axial moving structure. That is, the tow-spindle three-turret lathe which includes the two spindles opposed to each other on the same axis, the two turrets 16 arranged on a depth side of the axis, and the one turret 17 arranged on a lower front side of the axis, allows all the three turrets 16, 17 to move in an Y-axial direction under numerical control, and allows all the three turrets to have the rotation drive unit for the tool mounted on the same. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a lathe provided with two main spindles facing each other on the same axis and three turret tool posts arranged with the axis interposed therebetween.

  As is well known, a lathe has a spindle that grips and rotates a workpiece and a tool rest on which a tool is mounted. As a tool rest, a turret tool rest that can select a plurality of tools by indexing operation is generally used. It has become. Furthermore, there is also provided a lathe equipped with a rotating tool turret capable of mounting a rotating tool such as a drill or a milling cutter. In classic lathes that change tools by hand, the tool post is located on the front side of the spindle, but it has a turret lathe and automatic tool changer that do not require manual tool change during machining. The lathe tool post is usually arranged on the back side of the spindle in consideration of the operator's accessibility to the workpiece.

  A two-spindle facing lathe equipped with two spindles with the workpiece gripping ends facing each other on the same axis and two or more turrets cooperating with each spindle increases productivity by parallel machining with two spindles. There is a feature that the whole workpiece including the grip portion of the spindle chuck can be processed by being able to increase the height and transferring the same workpiece between the two spindles.

  Further, a lathe provided with a tool rotation drive device on the turret can use a rotary tool such as a drill or a milling cutter, and can drill or groove a work peripheral surface on the lathe. Further, by making the turret provided with a rotational drive device for the tool movable in the Y-axis direction, it is possible to machine the workpiece circumferential surface using an end mill. The Z axis of the lathe is the main axis direction, the X axis is the cutting feed direction of the cutter, and the Y axis is a direction perpendicular to both.

  A two-spindle facing lathe equipped with three or more turrets is also provided, and a single workpiece is simultaneously machined by two tool rests arranged across the spindle axis, thereby improving productivity. In addition, when a workpiece is transferred between two spindles, the balance between the machining times of both spindles is adjusted to reduce the waiting time, thereby reducing the machining time. In a two-spindle opposed lathe with three turrets, only one third turret tool arranged on one side of the spindle axis can be used for machining workpieces on both sides of the spindle, and is mounted on the machine. The number of types of tools that can be used is increased, making it possible to handle the machining of workpieces with more complex shapes.

That is, by adding a third turret equipped with a rotary drive device for a tool to a two-spindle two-turret lathe, the function or performance of the lathe can be greatly improved with a relatively small increase in machine cost.
Japanese Patent Laid-Open No. 2003-181705

  A lathe capable of Y-axis movement by NC control of a turret equipped with a tool rotation drive device can perform planar machining of a workpiece peripheral surface, and machining that is conventionally performed by a machining center can be performed by a lathe. Such planar processing of the workpiece peripheral surface often involves processing a parallel plane at a position opposed to the peripheral surface across the central axis of the workpiece. With a conventional two-spindle facing lathe equipped with a Y-axis movable turret, when machining a parallel plane at a position opposite to the workpiece peripheral surface, the spindle is fixed at a predetermined angular position and one plane of the workpiece is machined Then, the processing was performed in two steps, such as processing the opposite plane by fixing the main shaft at a position rotated 180 degrees.

  The present invention enables efficient machining of a workpiece having a complicated shape by allowing a lathe capable of machining a workpiece circumferential surface to more efficiently perform machining of a parallel plane of the workpiece circumferential surface and machining of a parallel hole. The challenge is to provide a lathe that can be machined well.

  The present invention adopts a driving device for a rotary tool such as a drill or an end mill and a Y-axis moving structure by NC control in all three turrets in a lathe having two main shafts and three turrets. Thus, the above problem is solved.

  That is, the two-spindle three-turret lathe according to the invention of claim 1 of the present application includes two spindles opposed on the same axis, and two turrets 16a and 16b arranged on the upper side of the axis, and the axis A two-spindle three-turret lathe provided with one turret 17 arranged on the lower side in front of each of the three turrets 16a, 16b, 17 can be NC-controlled and moved in the Y-axis direction, and All of the three turrets are provided with a rotary drive device for a tool attached to the turret.

  Further, the invention of claim 2 of this application is that, in a two-spindle three-turret lathe provided with the above means, the movement of the turret 17 arranged at least on the lower side of the main shaft axis in the turret in the Y-axis direction is X Movement of an X-axis feed base (lower tilt base 13 in the illustrated embodiment) having a guide surface 22 tilted with respect to the axis, and tilt feed base (shown in the illustrated embodiment) provided on the guide surface so as to be movable in a direction perpendicular to the main axis. The lower tool post 15) is combined with the movement of the lower tool rest 15).

  According to the present invention, parallel planes facing each other across the center axis of the workpiece can be simultaneously performed using the rotary tools of the upper and lower turrets and the Y-axis movement, and the axes are offset in the vertical direction to face each other. Thus, it is possible to simultaneously process the two holes, so that it is possible to greatly improve the machining efficiency of a workpiece having a complicated shape.

  Hereinafter, an example of a preferred embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a schematic front view showing the arrangement of two spindles and three turrets (viewed with the bed upper surface facing forward). 1 is a bed, 2 is a left spindle head fixed to the bed 1, and 3 is a bed upper surface. Z-axis main shaft guide provided on the right, 4 is a right main shaft that can move along the main shaft guide, 5 is a left chuck mounted on the right main shaft side end of the left main shaft, and 6 is a left main shaft of the right main shaft. A right chuck 7 attached to the side end is a feed motor for the right headstock 4.

  8 is an upper Z-axis guide provided on the upper surface of the bed, 9 is the lower Z-axis guide, 10 is an upper Z slide that moves along the upper Z-axis guide 8, and 11 is a lower Z that moves along the lower Z-axis guide 9. Slide, 12 is an upper tilt base mounted on the upper Z slide 10, 13 is a lower tilt base mounted on the lower Z slide 11, and 14 is an upper tool rest (left upper tool rest 14a and upper right base mounted on the upper tilt base 12) The turrets 14b) and 15 are lower turrets mounted on the lower inclined pedestal 13, the upper turrets 16 are mounted on the upper turret 14 (the upper left turret 16a and the upper right turret 16b), and 17 are mounted on the lower turrets 15. The lower turret. The tilt tables 12 and 13 are X-axis feed tables that are fed in the X-axis direction, and the tool tables 14 and 15 are tilt feed tables that are fed in the tilt direction of the tilt table.

  The tool rests 14 and 15 incorporate an indexing device for indexing the turrets 16 and 17 and a rotating tool driving device for driving a rotating tool mounted on the turret. Reference numeral 18 denotes a Z-axis feed motor for the upper left tool rest 14 a, 19 denotes a Z-axis feed motor for the upper right tool rest 14 b, and 20 denotes a Z-axis feed motor for the lower tool rest 15.

  FIG. 2 is a side view showing the X-axis and Y-axis feed structures of the upper turret 16 and the lower turret 17. The upper surface of the bed 1 is inclined by 60 degrees with respect to the horizontal plane so that the operator side is lowered, and the X-axis direction is a direction inclined by 60 degrees with respect to the horizontal plane parallel to the upper surface of the bed. The Z axis is a direction perpendicular to the paper surface of FIG. 2, and the Y axis is a direction orthogonal to the X axis in the plane of FIG.

  An X-axis guide 21 is provided on the upper surface of the upper Z slide 10 and the lower Z slide 11 that move in the Z-axis direction along the upper Z-axis guide 8 and the lower Z-axis guide 9 and is mounted on the Z slide. The inclined bases 12 and 13 are movable along the respective X-axis guides. The upper surfaces of the upper inclined table 12 and the lower inclined table 13 are inclined 45 degrees in the direction in which the main shaft side is lowered with respect to the X axis, and an inclined guide 22 in the inclined direction is provided on the upper surfaces of the inclined tables 12 and 13. It has been. The upper and lower tool rests 14 and 15 mounted on the upper and lower tilt bases 12 and 13 are movable along the tilt guide 22.

  Reference numeral 23 denotes an upper X-axis feed motor that sends the upper tilt table 12 in the X-axis direction, and reference numeral 24 denotes an upper tilt feed motor that sends the upper tool rest 14 in the tilt direction. The upper X-axis feed motor 23 and the upper inclined feed motor 24 are provided on extension axes of feed screws (not shown) in the respective directions, and the left and right upper tool rests have the same structure. 3 is a lower X-axis feed motor for feeding the lower tilt base 13 in the X-axis direction, and 26 is a lower tilt feed motor for feeding the lower tool post 15 in the tilt direction. These are the lower tilt feed motors as shown in FIG. It is mounted on the left side of the Z slide 11 and the lower inclined base 13 with its output shaft facing downward, and is connected to an X feed screw and an inclined feed screw (not shown) by a synchronous belt (not shown). Reference numerals 27 and 28 shown in FIGS. 2 and 3 denote covers for these synchronous belts.

  In the above structure, in order to feed the tools mounted on the turrets 16 and 17 in the X-axis direction, the X-axis feed motors 23 and 25 may be driven with the tilt feed motors 24 and 26 stopped. On the other hand, when sending the tool in the Y-axis direction, the X-axis feed motors 23 and 25 send the tilt bases 12 and 13 by the desired Y-direction feed amount, and the tool rests 14 and 15 in the tilt direction have the X-direction feed amount. Although the feed amount is twice the route, the positive direction of the Y axis is the opposite direction (point symmetric with respect to the center of the spindle) in the upper and lower tool rests, so by setting the control parameters of the NC device, Reverse feed direction up and down.

  That is, when the tool mounted on the upper turret 16 is sent in the Y-axis plus direction (direction away from the bed 1), the upper X-axis feed motor 23 sends the upper inclined base 12 in the minus direction (direction approaching the main axis). Then, the upper tool rest 14 is fed in the plus direction of the inclination (direction away from the main shaft) with a feed amount twice the route of the X-direction feed amount. Conversely, when the tool is sent in the Y-axis minus direction, the upper tilt base 12 is sent in the X-axis plus direction, and at the same time, the upper tool rest 14 is sent in the minus direction of the tilt with a feed amount twice the route of the X-direction feed amount.

  On the other hand, when the tool mounted on the lower turret 17 is fed in the Y-axis plus direction (direction approaching the bed 1), the lower tilt base 13 is moved in the X-axis plus direction (direction away from the main axis) by the lower X-axis feed motor 25. At the same time, the lower tool rest 15 is fed in the minus direction of the inclination (direction approaching the main shaft) with a feed amount that is twice the route of the feed amount in the X direction. Conversely, when the tool is sent in the Y-axis minus direction, the lower tilt base 13 is sent in the X-axis minus direction, and at the same time, the lower tool rest 15 is sent in the tilt plus direction at a feed amount twice the route of the X-direction feed amount.

  That is, in the structure of the illustrated embodiment, both the Y-axis direction feed of the upper tool rest 14 and the lower tool rest 15 are realized by a combined operation of the X-axis direction feed and the tilt direction feed. The Y-axis feed structure based on such a composite operation is characterized in that the feed structure can be made compact and the support rigidity of the tool post 14 can be increased, and the X-axis feed motor 25 and the tilt feed motor 26 shown in FIG. By arranging the slide 11 and the tilt table 13 on the side, the tool post can be made more compact.

  FIG. 4 is a sectional view showing an indexing mechanism and a rotary tool driving mechanism built in the tool rests 14 and 15. A hollow indexing shaft 32, a hollow fixed shaft 33, and a rotation transmission shaft 34 are coaxially supported on a casing 31 integrated with the tool post. The hollow index shaft 32 is rotatable with respect to the casing 31, a turret case 35 is fixed to the distal end thereof, and an index gear 36 is fixed to the proximal end side. The indexing gear 36 is meshed with a drive gear 38 fixed to the output shaft of an indexing reduction motor 37 mounted on the side surface of the casing 31. A fixed surface gear 39 and a rotating surface gear 40 for fixing the index position are fixed to the front end of the casing 31 and the rear surface of the turret case 35, and the idler surface gear 41 faces these. The idle surface gear 41 is provided on the end surface on the turret case side of the piston 52 fitted in the ring-shaped cylinder 51 formed between the casing 31 and the hollow indexing shaft 32 to index the tool. When rotating the turret, the piston 52 is moved to the left in the figure to disengage the idle surface gear 41, and when fixing the indexed tool, it is moved to the right to rotate the idle surface gear 41 with the fixed surface gear 39. By simultaneously meshing with the surface gear 40, the rotating surface gear 40 and thus the turret case 35 is fixed.

  The hollow fixed shaft 33 is supported by the hollow indexing shaft 32 so as to be relatively rotatable, and the base end is connected to the casing 31 via a power lock (fixing tool) 44 or the like, so that rotation and axial movement are impossible. It has become. An inner case 42 built in the turret case 35 is fixed to the distal end of the hollow fixed shaft 33, and a tool drive shaft 43 perpendicular to the turret shaft is supported on the inner case 42. Therefore, the tool drive shaft 43 does not turn even when the turret case 35 rotates, and always faces a certain direction (work direction).

  The rotation transmission shaft 34 is pivotally supported by the hollow fixed shaft 33 so as to be freely rotatable, and the tip thereof is connected to a drive bevel gear 45. The drive bevel gear 45 meshes with a driven bevel gear 46 provided on the tool drive shaft 43. The tool drive motor 47 is provided with its output shaft 48 aligned with the axis of the rotation transmission shaft 34 and fixed to the side opposite to the turret case of the casing 31, and the tool drive motor output shaft 48 and the rotation transmission shaft 34. Are coupled by a coupling 49.

  When a rotary tool 59 such as a drill or a milling cutter is mounted on the turret, these tools are mounted on a tool mounting station provided on the outer periphery of the turret case 35 with the tools mounted on the tool mounting shaft 55 of the rotary tool holder 54. . A diametrical projection 56 is provided at the proximal end of the tool mounting shaft 55, while a corresponding diametrical groove 57 is provided at the distal end of the tool drive shaft 43. When the rotary tool holder 54 is mounted on the turret case 35, the projection 56 and the groove 57 are fitted, and the rotation of the tool drive motor 47 is transmitted to the tool mounting shaft 55 via the rotation transmission shaft 34 and the tool drive shaft 43. Is done.

  When the turret case 35 is rotated to index another tool, the protrusion 56 must be removed from the groove 57. Therefore, a motor capable of stop phase control is used as the tool drive motor 47 so that the tool drive shaft 43 always stops with the groove 57 in the circumferential direction. On the other hand, a circumferential groove 58 for guiding the projection 56 of the tool mounting shaft is provided on the circumferential surface of the inner case 42, and when the rotary tool moves to another position, the rotation of the projection 56 causes the circumferential groove of the inner case to rotate. This is prevented by 58 so that the direction of the protrusion 56 does not change. Therefore, when the rotary tool is again indexed to the processing position on the extension of the tool drive shaft 43, the protrusion 56 and the groove 57 are fitted without colliding.

  In the two-spindle three-turret lathe having the above structure, when machining a parallel plane at a position opposed to the work peripheral surface, the spindle is fixed so that the direction of the plane is the Y-axis direction, and the lower turret 17 is moved to the left or right. By moving to the position facing the upper turret 16 and moving the milling machine mounted on the upper and lower turrets toward the workpiece in the X-axis direction, the upper and lower turrets 16 and 17 are moved in the Y-axis direction while rotating the milling cutter. Simultaneous processing. At this time, when the workpiece is gripped by the left chuck 5, the upper left turret 16 a and the lower turret 17 are processed at the same time. When the workpiece is gripped by the right chuck 6, the upper right turret 16 b and the lower turret 17 are processed simultaneously. is there. Even when tapping holes at right angles to the four corners of the machined opposing plane are machined, the drill or tap is indexed at the same position, and the tool is moved to the hole machining position by moving the turret Z and Y axes. Simultaneous operation is possible by performing the operation of moving the turret in the X-axis direction while rotating it in parallel with the upper and lower turrets.

Schematic front view showing the arrangement of two opposing spindles and three turrets Side view showing the guide structure of the tool post in the X-axis direction and the Y-axis direction The perspective view which shows arrangement | positioning of the X-axis and synthetic | combination axial feed motor of a lower tool post Sectional view showing the drive mechanism of the tool axis provided on the tool post

Explanation of symbols

13 Lower tilt base
15 Lower tool post
16a Upper left turret
16b Upper right turret
17 Lower turret
22 Inclination guide

Claims (2)

  Two turrets having two main shafts facing each other on the same axis line, two turrets (16a, 16b) arranged on the upper side of the axis line, and one turret (17) arranged on the front lower side of the axis line In the two-spindle three-turret lathe provided, all of the three turrets (16a, 16b, 17) can be controlled by NC control in the Y-axis direction, and all of the three turrets are connected to the turret. A two-spindle three-turret lathe comprising a rotary drive device for the attached tool.   An X-axis feed base (13) provided with a guide surface (22) inclined with respect to the X-axis by the movement in the Y-axis direction of the turret (17) disposed at least on the lower side of the main axis in the turret. 2. The two-spindle three-turret lathe according to claim 1, wherein the two-spindle three-turret lathe is combined with a movement of an inclined feed base (15) provided on the guide surface so as to be movable in a direction perpendicular to the spindle.

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