JPH074681B2 - NC lathe - Google Patents

Description

Description: FIELD OF THE INVENTION The present invention relates to an NC lathe having opposed headstocks.

2. Description of the Related Art Conventionally, in turning processing by a center work for machining a shaft work using a tailstock, pre-processing of both end surfaces, both center holes, gripping part outer diameter, etc. is required, and even if a turning process is started. Since the part held by the chuck cannot be processed, it is necessary to divide the process into two parts. For this reason, the number of steps is usually three, including the previous step.

Problems to be Solved by the Invention In turning processing in center work described in the conventional art, since there are many steps, waiting between steps occurs, and takt balance between each step is not achieved However, there is a problem that a dedicated centering machine is required to separate only the pre-processing.

The present invention has been made in view of such problems of the conventional technique, and an object of the present invention is to perform all the processes including the pre-process continuously by one machine.
It intends to provide an NC lathe.

Means for Solving the Problems To achieve the above object, the NC lathe of the present invention is provided with a multi-blade tool that rotates together with the main shaft in the center holes of both main shafts so as to be movable in the axial direction, and a drive that moves the multi-blade tool. And a work gripping device capable of gripping the work on the tool rest turret in the direction of the center line of the spindle so that both ends, the outer periphery and / or the center hole of the work can be machined by a multi-blade tool. Is.

In addition, a center attachment / detachment device for automatically attaching / detaching the center to / from both spindle chucks is provided so that both edges of the workpiece, the outer peripheral portion and the center hole can be machined by a multi-blade tool so that all machining of the center workpiece can be continuously performed You can also do it.

Action Hold the workpiece on the workpiece holding device, rotate the cutter along with the spindle, position the tool rest turret at the position where the workpiece is concentric with the spindle, and cut both spindle stocks toward the workpiece side in the Z-axis direction at the same time. It moves by feeding to machine the outer diameter of the grip, the center hole, and the end face at the same time. Next, the cutter is retracted, and one spindle chuck grips the outer diameter of one side of the workpiece that has been pre-processed, and the other spindle chuck grips the center by the center attachment / detachment device. The outer diameter turning of the first step is carried out by supporting the. Next, the workpiece is gripped by the other spindle chuck, the center is gripped by the one spindle chuck to support the workpiece, and the outer diameter turning in the second step is performed.

EXAMPLE An example will be described with reference to FIGS. 1 and 2. In a known NC lathe, a left headstock 1 and a right headstock 2 facing each other are mounted on a slide guide surface in the Z-axis direction cut on a bed so as to be movable and positionable. Main shafts 3 and 4 are rotatably supported on the shaft 2.
Chucks 5 and 6 are fitted to the tips of the respective spindles 3 and 4, and the chucks 5 and 6 form draw tubes by the pistons of rotary cylinders 7 and 8 provided at the rear ends of the spindles 3 and 4, respectively. It is designed to be opened and closed through. Cutters 11 and 12 that have end face cutting bits 11c and 12c and outer peripheral cutting bits 11a and 12a outside the center drills 11b and 12b in the center holes of the chucks 5 and 6 axially move in the chuck center holes. It is movably fitted and rotated together with the chuck. Cutters 11 and 12 are rotating cylinders 7 and 8
The pistons are fitted to the concentric rotary cylinders 13 and 14 fixed to the rear end face of the cylinder and the connecting rods 15 and 16 are integrally connected, and can be moved into and out of the cutting position and the retreat position by switching the pressure oil. ing.

Each headstock 1 and 2 is provided with a center attachment / detachment device 17/18, and the L-shaped arms 21/22 of the center attachment / detachment device have openable / closable grasping claws for grasping the centers 19/20 at their tips. It is possible to move in the Z-axis direction and turn in the X-axis plane by a driving means (not shown), and the center gripped by this turning is indexed to a mounting / detaching position concentric with the main shaft and a retracted position on the lower side. There is.

Furthermore, a tool post 24 that can be moved and positioned in the X-axis and Z-axis directions
In addition, the work gripping device 26 is attached to one of the tool attachment stations of the turret 25 which is provided so as to be rotatable and indexable. The work gripping device 26 has two gripping claws at distant positions, and grips the shaft work 27 in the Z-axis direction with a strong force that can withstand cutting.

Next, the operation of this embodiment will be described with reference to FIGS. In FIG. 3, pressure oil is supplied to the rear chambers of the rotary cylinders 13 and 14, the cutters 11 and 12 are moved forward, and the end faces of the cutters and the outer diameter cutting bits 11a and 12a are separated from the tip faces of the grip claws of the chucks 5 and 6. Stop at a slightly protruding position. X of the turret 24
By the axial movement, the workpiece 27 is positioned concentrically with the spindle, and the headstocks 1 and 2 are simultaneously moved to the workpiece side in the Z-axis direction at the cutting feed rate, the outer diameter cutting by the cutting tools 11a and 12a, and the cutting tools 11c and 12c. End face cutting with the center drills 11b and 1
The center hole cutting by 2b is performed at the same time. When the cutting is completed, the headstocks 1 and 2 move to the Z-axis direction anti-workpiece side, and the rotation of the cutter is stopped. In FIG. 4, the rotary cylinder 1
Pressure oil is supplied to the front chambers of 3,14 and the cutters 11, 12 retract,
After the headstock 2 is moved slightly to the right, the arm 22 of the center attachment / detachment device 18 is swung by the attachment / detachment device, and the center 20 to be gripped becomes concentric with the chuck 6, and the arm 22 is moved to the right side to move the center 20 to the chuck. The pressure oil that is inserted into the gripping claws and is supplied to the rotary cylinder 8 is switched to close the gripping claws.
The center 20 is gripped. At the same time, the headstock 1 moves slightly rightward to position the workpiece gripping end surface of the chuck 5 at a position where it coincides with the end surface of the workpiece 27, the pressure oil supplied to the rotary cylinder 7 is switched, and the gripping claws are closed. The pre-machined outer diameter on the left side of the workpiece is gripped. Next, the headstock 2 moves to the left, the center 20 is inserted into the right center hole of the workpiece 17 and pressed into contact with the workpiece to support the workpiece, and the gripping jaws of the workpiece gripping device 26 are opened to retract the tool rest 24 in the X-axis direction. Away from the work piece by turret
25 turns and the cutting tool T1 for the first step is indexed to the cutting position. Next, the main shaft is rotated, the tool tip is moved in the Z-axis and X-axis directions to position the cutting edge of the tool T1 at the cutting start position, and then the cutting feed of the tool post performs the outer diameter cutting in the first step on the right side. When the outer diameter cutting is completed, the tool rest 24 is retracted to the predetermined retracted position and the rotation of the spindle is stopped. In FIG. 5, the headstock 2 moves to the right and the center 20 separates from the work 27, the center 20 is detached and retracted by the center attaching / detaching device, and the headstock 2 moves to the left to move the work gripping end surface of the chuck 6. But the work piece 17
Is positioned at a position corresponding to the right end surface of the workpiece, the grip claw is closed, and the outer diameter of the right end portion of the workpiece is gripped. Then chuck 5
Open, the spindle head 1 moves slightly to the left, the arm 21 of the center attachment / detachment device 17 turns, the center 19 for gripping becomes concentric with the chuck 5, and the arm 21 moves left and the center 19 grips the jaws of the chuck 5. Inserted in 10, the grip claws are closed and the center 19 is gripped. Next, the headstock 1 moves to the right and the center 19 is inserted into the left center hole of the workpiece 27 and press-contacted, so that the left side of the workpiece is the center 19
The cutting tool T2 for the second process is indexed to the cutting position by the turret 25 turning by the turret 25, and the cutting edge of the tool T2 is positioned at the cutting start position by the movement of the tool rest 24 in the Z axis and the X axis. By the cutting feed of the tool rest 24, the outer diameter cutting of the remaining second part of the workpiece 27 is performed.

In this embodiment, the description has been given of the case where both headstocks 1 and 2 are movable in the Z axis, but the toolstock can be fixed even if one headstock 1 is fixed.
The same effect can be obtained by providing 24 and the other headstock 2 with the Z-axis synchronous feed function.

EFFECTS OF THE INVENTION Since the present invention is configured as described above, it has the following effects.

A cutter that shares the end face, outer diameter cutting tool, and center drill is provided in the center hole of each of the two facing spindle headstocks that have the Z-axis movement positioning function so that the cutter can share the work piece. A machine and a center attachment / detachment device for each headstock are provided to automatically attach / detach the center to / from the spindle chuck, so that all machining including end face, gripping part outer diameter and centering machining can be performed continuously by NC control. This makes it possible to improve processing efficiency and integrate processes, and it is easy to deal with setup changes and work changes.

[Brief description of drawings]

FIG. 1 is an explanatory view of the NC lathe of this embodiment, FIG. 2 is an enlarged view of the right cutter, FIGS. 3 to 5 are for explaining the operation, and FIG. 3 is both end faces, outer diameter of gripping part and center. FIG. 4 is an explanatory diagram showing hole machining, FIG. 4 is an explanatory diagram showing machining in the first step of outer diameter turning, and FIG. 5 is an explanatory diagram showing machining in the second step of outer diameter turning. 1 …… Left headstock, 2 …… Right headstock 5,6 …… Chuck, 11,12 …… Cutter 19,20 …… Center, 25 …… Turret 26 …… Work gripping device

Claims (2)

[Claims] 1. An NC lathe having at least one opposing headstock (1,2) capable of moving and positioning in the Z-axis direction, a multi-blade which rotates together with the main spindle in the central holes of both main spindles (3,4). A tool (11, 12) is provided so as to be movable in the axial direction, drive means for moving the multi-blade tool is provided, and a tool rest turret (2
An NC lathe characterized in that a workpiece gripping device capable of gripping the workpiece (27) in the spindle centerline direction is provided in 5) and both ends, the outer peripheral portion and / or the center hole of the workpiece can be machined by a multi-blade tool. . 2. A center (19, 20) is provided with a double spindle chuck (5, 6).
A center attachment / detachment device (17, 18) for automatic attachment / detachment is provided, and both ends, outer periphery and center hole of the work are processed by the multi-blade tool (11, 12), and then all the center work is continuously processed. The NC lathe according to claim 1, which is capable of