JPS58192701A - Back side machining method of work in numberically controlled lathe - Google Patents

Abstract

PURPOSE:To improve working efficiency, by a method wherein one main spindle is provided with at least two turret tool rests, holding of a work is corrected after completion of its first process and a second process of the back side of the work is carried out by the second turret. CONSTITUTION:A bar 4 is held by a main spindle chuck 3 and when a first process machining is completed, a grip 7 is indexed at a predetermined position by slewing a first turret fed 6. A first tool rest 5 is moved in a Z direction after a first tool rest has been moved in the X direction and a collet 14 has been made to coincide with an axial line of a main spindle and to move in the Z direction, and a machined edge of the bar 4 is made to hold by the collet 14. A cut-off tool of a second turret rest 9 is indexed at a machining position after that, a second tool rest 8 is moved in the Z direction and the bar 4 is cut off in a fixed length.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for machining the back side of a workpiece in a numerically controlled (hereinafter referred to as NC) lathe having at least two turret tool posts.

After machining one end of the workpiece as the first step on the NC lathe,
In the second step, when processing the other end, which is the cut surface of the bar material that was previously chucked during the first step, conventionally, the workpiece that was cut by the operator or a loader with a reversing device was processed. A workpiece that is about to be gripped or cut is gripped, and after being cut, the workpiece is turned over and gripped by a chuck on the main shaft of another machine. However, if the work is done by an operator, it is not possible to automate the work, and if the loader is equipped with a reversing device, the structure of the loader itself is complicated, large, and therefore expensive. It has the disadvantage that it is long and requires a separate machine for processing the cut surface.

The present invention has been made in order to eliminate the above-mentioned drawbacks, and aims to provide a method for machining the back surface of a workpiece by effectively utilizing two turrets. In an NC lathe that involves a turret tool post, the workpiece after the first process is gripped by a rotatable collet of a gripper device attached to the first turret tool post, the workpiece is transferred from the spindle chuck, and then the workpiece is transferred from the spindle chuck. The rotation of the gripper device is transmitted to the chuck of the gripper device, and the back side of the workpiece is machined on the second left tool rest.

Embodiments of the present invention will be described below with reference to the drawings in the case of bar material processing. A main spindle 2 having a through hole is horizontally supported on a headstock 1 mounted on the bed of a four-axis controlled NC lathe (not shown), and a chuck 3 is attached to the tip of the main spindle 2. A bar material 4, which is a workpiece, is inserted into the through hole of the spindle 2, and is gripped by a chuck B, and the bar material is fed forward as appropriate by a known bar feeder (not shown) provided at the rear of the headstock 1. sent to. The axial direction of the main shaft 2 (
Z direction) and a direction perpendicular to this Z direction (X direction)
A first tool rest 5 is movably provided and controlled by an NC, and an ls1 turret rest 6 is attached to this first tool rest 5. The first talent table 6 can be rotated and indexed about the axis in the Z direction, and a unit-shaped gripper device 7 capable of gripping the bar material 4 in addition to the cutting tool is detachably attached to the outer peripheral surface. . Also, it can be moved in the direction of the propeller #l! A second tool rest 8 is provided and controlled by an NC, and an fH2 talent rest 9 is attached to the second tool rest 8 so as to be rotatable and indexable about an axis In in the Z direction. A large number of cutting tools are attached to the outer peripheral surface of the second turret stand 9. The gripper device 7 is #11
A main body 10 fastened to the turret stand 6, and this main body 1
A first rotary shaft 11 is supported parallel to the Z direction and whose shaft end is supported by a sphere 17 so as to serve as a stopper for the fed bar material and withstand strong pressing force; a second rotary shaft 12 grips the workpiece; The rotation of the first rotating shaft 11 is controlled by an elastic friction member 13 such as rubber attached to the tip of the first rotating shaft 11 and a fret member 14 for gripping the bar material attached to the tip of the second rotating shaft 12. The first
・#l! It is comprised of two rotating shafts with mutually meshing i-gears 15 and 16, which are respectively keyed.

Next, the effect will be explained. It is assumed that the main spindle 2 is stopped, the bar material 4 is gripped by the main spindle chuck 3, and the first step of machining of the bar material 4 has been completed. The first turret stand 6 is rotated and the gripper device 7 is indexed to a predetermined position. #! 1 Turret 5 [Move in the -X direction and collet 1
4 is aligned with the main axes, and then moved in the Z direction, the collet 14 grips the processed end of the bar material 4.
Thereafter, the main shaft 2:4 is rotated, the parting tool of the lJ2 turret stand 9 is indexed to the processing position, the second tool rest 8 is moved in the Z direction, positioned at a predetermined position, and the bar material 4 is sent in the X direction with the parting tool. Cut it to a specified length.

The main shaft 2 is stopped, the first tool rest 5 is moved, and the friction member 1 is
3 are aligned with the main axes and positioned at a predetermined distance from the end face of the chuck 3. The chuck 6 is opened and the bar material 4 is moved one step forward using a bar feeder to be brought into pressure contact with the friction member. When the chuck 3 is closed and the main shaft 2 is rotated in this state, the rotation of the main shaft is caused by the friction member 13. First rotating shaft 11. Gears 15 and 16 are transmitted to the second rotating shaft 12 and rotate the workpiece gripped by the gears 14. after that#! While moving the second turret 8, the required tool is indexed from among the various cutting tools attached to the second turret 9, and the # of the workpiece held by the collet 14 is determined. Perform back side processing in two steps. By changing the number of rotations of the main shaft 2, it is possible to give the workpiece in the collet 14 an optimum number of rotations depending on the machining process. Alternatively, a cut-off step may be performed during the first step, and the workpiece may be gripped by the collet 14 just before the cut-off step.

Next, another example of the present invention is shown #! Figure 5 will be explained. The gripper device body 1o has a collet 14 at its tip.
Only one rotating shaft is supported, and a friction wheel 18 made of an elastic material is fixed concentrically to this rotating shaft. When machining the back surface of a workpiece, a friction wheel 17 is pressed against the outer periphery of the cylindrical portion of the bar material 4 that protrudes by a predetermined distance from the spindle chuck 3 to directly transmit rotation to the collet mounting rotating shaft.

In this case, the number of parts can be reduced by half, resulting in a simpler structure and lower cost. In the above description, a bar material was used as the workpiece, but the present invention can also be used for machining the back surface of a seven-lung-shaped workpiece.

As detailed above, in the present invention, the workpiece gripped by the spindle chuck is transferred to the chuck that is rotated by the spindle rotation of the gripper device attached to the turret stand, and the back surface machining is performed on another turret stand. Therefore, there is no need for a special reversing operation for processing the back surface, and there is no need for a special drive source for the gripper device, so that processing can be performed at low cost and without wasted time, and the work efficiency can be improved.

[Brief explanation of the drawing]

Figure 1 is a schematic diagram showing the state in which a workpiece is being cut by the two tool rests. Figure 2 is a schematic diagram showing the state in which a workpiece is gripped by a gripper device and parting is being performed. Schematic diagram when processing the back side of an object @ Figure 4 is an enlarged detailed diagram of the gripper device #! FIG. 5 is a schematic diagram showing another embodiment of the gripper device. 2... Main shaft 3... Chuck 4... Bar material 6... First turret stand 7... Gripper device 9... Second turret stand 13... Friction member 14... Collet 17 ...friction wheel

Claims (1)

[Claims] (1) In a numerically controlled lathe in which at least two turret stands are involved for one spindle, the workpiece gripped by the chuck at the tip of the spindle is rotatably gripped in a gripper device attached to the first talent stand. I changed my grasp on the means,
By transmitting the rotation of the main shaft to the gripping means in the gripper device, the gripped workpiece is rotated #! 2. A method for machining the back surface of a workpiece in a numerically controlled lathe, the method comprising machining the back surface of the workpiece using a cutting tool attached to a turret stand.