JPH05285702A - Lathe - Google Patents

Abstract

PURPOSE:To provide a compact lathe of high working performance having two head stocks and one and more tail stocks. CONSTITUTION:The first and the second head stocks 132 and 134 are fixed on a body frame 131, and the first and the second main spindle chucks 136 and 150 mounted respectively at the tips of the first and the second main spindles 138 and 152 hold rotatably the first and the second main spindles 138 and 152 in concentric and facing condition each other. The first and the second tail stocks 164 and 166 are mounted between the first and the second head stocks 132 and 134 to hold workpieces respectively by means of the first and the second centers 182 and 194, and the workpieces are processed in the order of the first head stock 132 and the second head stock 134. The first and the second head stocks 132 and 134 are mounted so as to face each other, their distance is short and working and carrying of workpieces are easy, and moreover space between the first and the second head stocks 132 and 134 are available as a common space for working and device setting.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lathe having two headstocks, and more particularly to the arrangement of a headstock and a tailstock.

[0002]

2. Description of the Related Art A lathe is for rotating a workpiece and moving a processing tool to perform processing on the workpiece. Therefore, a lathe is generally configured to include a main body frame and a headstock fixed to the main body frame and having a main spindle that holds and rotates a workpiece. When the work piece has a short length for its diameter, a spindle chuck is attached to the tip of the main spindle, and the work piece is attached thereto. On the other hand, when the workpiece is a shaft having a long length for its diameter, a tailstock concentrically opposed to the main shaft is used. A center is provided at the center of the spindle chuck, and both ends of the workpiece are supported by the center and the center of the tailstock, and the spindle chuck grips the ends of the workpiece and transmits the rotation of the spindle. It is.

Some lathes have two headstocks. By doing so, two types of processing can be performed in parallel at the same time, the processing efficiency is improved, and moreover, it can be constructed at a low cost and compactly as compared with the case where two lathes are provided independently. Of. When two headstocks were provided, they were provided in parallel on the base.

[0004]

However, conventionally, since two headstocks are provided in parallel on the base, there is a problem in workability. When two headstocks are installed in parallel and work such as replacement of the work piece, inspection of the headstock, and cleaning are performed from the direction orthogonal to the axis of rotation of the spindle, the depth is deep and It is difficult to work, and if you try to work from the side parallel to the axis of the spindle, the distance to the two headstocks is the same, but you can hold the work or machining tool on the front side of the headstock. Since a slide or the like that moves in a horizontal direction is provided, the distance to the main shaft becomes long and the work is difficult to perform.

It is also conceivable to provide two headstocks in series in the same direction. In this case, when working from a direction orthogonal to the rotation axis of the main spindle, the distances to the two headstocks are the same. Although the work can be easily performed on any headstock, it is possible to avoid the workability being deteriorated because it takes time to move because the chuck of one spindle and the chuck of the other spindle are separated. Absent. Also, cleaning,
Space for carrying out inspections, equipment for carrying out processing waste, etc. 1
It is necessary to provide two required spaces and two devices for each headstock, resulting in a large machine tool and high cost.

The problem caused by providing two such headstocks similarly occurs when a tailstock is provided to support the workpiece, and when two headstocks are provided in series, This problem becomes particularly noticeable. It is an object of the present invention to provide a lathe having two headstocks and a tailstock provided for at least one of the two headstocks, which has excellent workability and is compact. It was made as.

[0007]

In order to solve the above-mentioned problems, a lathe according to the present invention comprises (a) a main body frame,
(B) a first headstock having a first spindle fixed on the body frame and holding and rotating a workpiece; and (c) fixed on the body frame and concentrically opposed to the first spindle. A second headstock provided with a second headstock for holding and rotating a workpiece, and (d) a position provided between the first headstock and the second headstock of the main body frame, and the first head is provided at the tip. The gist of the present invention is to include a tailstock that concentrically faces the main shaft and has a center that can move on the rotation axis of the first main shaft.

The tailstock may be provided only for the first headstock or for both the first headstock and the second headstock.

[0009]

In the lathe constructed as described above, machining of the shaft is performed using the spindle chuck and tailstock,
Machining of short workpieces is done using only the spindle chuck. In any case, since the two headstocks are fixed on the base and the first and second spindles are concentric with each other and face each other, work is performed from the direction orthogonal to the rotation axis of the spindle. The distance between the first and second headstocks is the same, and the distance between the first and second headstocks is short,
The space between them can be used as a common space.

[0010]

As described above, according to the present invention, work can be easily performed on both the first and second headstocks, and the distance between the first and second headstocks is reduced. Since the length is short, the time required for the movement is short, and the object to be held between the main shafts can be conveyed quickly. Also, the space between the first and second spindles becomes a common work space, and the machine tool can be made compact compared to the case where a space for maintenance and inspection is secured for each, and the space Since the device can be installed and shared, the cost can be reduced. Furthermore, since the first and second headstocks are both fixed on the base,
Since the first and second spindles are held with high rigidity, machining can be performed with high accuracy.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described in detail below with reference to the drawings. As shown in FIGS. 2 and 3, the main lathe is provided in the housing 10. Housing 1
Reference numeral 0 denotes a box shape, the inside of which is divided into two by a partition wall 14 provided upright on the edge of the base 12 as shown in FIG. The other is a transfer chamber 20 in which the work is transferred by the work transfer robot 18.

The front wall 22 which constitutes the transfer chamber 20 together with the partition wall 14 of the housing 10 is provided with two doors 24 and 26 that are opened so as to be opened in a reversed manner, and is provided with a window 28. It is designed so that you can look inside. An operation panel 30 is also provided on the front wall 22. Further, although not shown, a pair of side walls forming the transfer chamber 20 respectively receives a work from a work supply device provided adjacent to the housing 10 and carries the work into the transfer chamber 20, A work carry-out port for carrying out already-worked work is provided. The partition wall 14 also includes two doors 44 and 46 as shown in FIG.
Are provided independently at a short distance,
It is designed to open in opposite directions.

The work transfer robot 18 provided in the transfer chamber 20 is slidably fitted to a guide rail 50 attached to the front surface of the base 12 in the Z-axis direction (left and right direction in FIG. 1) and is not shown. It is moved in the Z-axis direction by the moving device. The work transfer robot 18 includes a turntable 52 that can turn about a vertical axis, a turn arm 54 that can turn about a horizontal axis, and first and second turn arms 54 provided at the tip of the turn arm 54. Transport chucks 56 and 58.

These transfer chucks 56 and 58 are provided back to back on a wrist 60 at the tip of the rotating arm 54.
As shown in FIG. 6, the wrist 60 is made up of a plurality of members fixed to each other, and is capable of intermittent rotation by 90 degrees in both forward and reverse directions around the axis parallel to the longitudinal direction of the turning arm 54. It is installed.

Workpiece W to be processed in this embodiment
Is a shaft having a long length relative to the diameter, and the first and second transfer chucks 56 and 58 are supposed to be capable of gripping the shaft-shaped work W. These first and second transfer chucks 56, 5
The configuration of 8 is the same, and the first transport chuck 56 will be described in detail with reference to FIGS. 6 and 7.

The block 64 constituting the wrist 60 has a pair of cylinder bores 66, 6 parallel to the rotation axis of the wrist 60.
8 are provided in parallel, and pistons 7 are provided respectively.
Nos. 0 and 72 are fitted so as to be liquid-tight and movable, and gripping claws 74 and 76 are fixed to the ends of the pistons 70 and 72 protruding from the cylinder bores 66 and 68, respectively. Each of these gripping claws 74 and 76 has an L-shape, and one arm portion of the L-shape is opposed to each other. V-grooves 78 and 80 are respectively formed on the opposing surfaces of the pistons 70 and 80.
It is formed in a direction orthogonal to the moving direction of 72, and holds and positions the work W.

Further, one gripping claw 76 is provided on the piston 72.
The position is fixed so that it can be adjusted. The grip claw 76 has a groove 8 formed in the piston 72 in a direction extending in the moving direction.
The bolt 88 is screwed through the elongated hole 86 formed in the grip claw 76 and is fixed to the piston 72 in a state where the bolt 88 is fitted into the groove 82 and the position in the groove 82 is adjusted by the adjusting bolt 84. The position of the grip claw 76 is set to the work W.
Can be changed according to the size of.

The pistons 70, 72 are provided with racks 92, 94 on the surfaces of the pistons 70, 72 facing each other in the middle of their movement direction, and are engaged with a pinion 96 rotatably mounted on the block 64. Therefore, if hydraulic fluid is supplied to the hydraulic chamber 98 and the piston 70 is moved in a direction projecting from the cylinder bore 66, the pinion 96 rotates counterclockwise in FIG.
Are drawn into the cylinder bore 68, and the grip claws 74 and 76 are brought close to each other to grip the work W.

When hydraulic fluid is supplied to the hydraulic chamber 100, the piston 72 is caused to project from the cylinder bore 68, while the pinion 96 is rotated clockwise in FIG. 6 so that the piston 70 is retracted into the cylinder bore 66. The gripping claws 74 and 76 are separated from each other to release the work W. The gripping claws 74 and 76 are opened and closed symmetrically to work W
Regardless of the diameter of the wrist, the axis of the wrist is always held at a fixed position with respect to the wrist 60.

The second transfer chuck 58 is also similarly constructed and has a pair of gripping claws 104 and 106, and each claw 10
Pistons 108, 110 holding 4, 106 are symmetrically moved by the rack and the pinion to open and close the gripping claws 104, 106 to grip and release the work W.

These first and second transfer chucks 56, 58
Among them, the first transfer chuck 56 is a loader chuck, receives the work W from the work supply device and delivers it to the spindle chuck, and the second transfer chuck 58 is an unloader chuck to receive the processed work W from the spindle chuck. Has been

First transfer chuck 5 which is a loader chuck
6, the grip claws 74 and 76 are designed to be tightened. In a portion of the block 64 between the piston 72 of the first transfer chuck 56 and the piston 110 of the second transfer chuck 58, the support member 114 has two bolts 115 (see FIG. 7).
A spring chamber 116 is formed so as to straddle the support member 114 and the piston 72. Stepped pins 118 and 120 for receiving springs are concentrically arranged in the spring chamber 116 so as to face each other, and are fixed to the piston 72 and the support member 114, respectively. A spring 122 is arranged between the stepped pins 118 and 120, and biases the piston 72 in the retracting direction to urge the gripping claws 74 and 76 in a direction to always close them. Therefore, even if the hydraulic pressure is not supplied to the hydraulic chamber 98, the first transport chuck 56 can continue to hold the work W.

Base 12 disposed in the processing chamber 16
As shown in FIGS. 1 and 2, a column 130 is vertically erected at the center in the width direction (left-right direction in FIG. 2) of the above and constitutes a main body frame 131 of the lathe together with the base 12. The column 130 has a length slightly shorter than that of the base 12, and a first headstock 132 and a second headstock 134 are fixed to the lower ends of the side surfaces of the column 130 on the side of the transfer chamber 20.

As shown in FIG. 1, the first spindle stock 132 has a first spindle 1 having a first spindle chuck 136 at its tip.
38 is rotatably supported about its axis. The first spindle chuck 136 is a three-claw chuck that grips and releases the work W by opening and closing three claws, and a center is provided at the center of the chuck so that the center can be moved back and forth between an operating position and a retracted position. .. A pulley 140 is provided at the rear end of the first spindle 138.
Are attached so that they cannot rotate relative to each other, and are connected to a pulley 146 fixed to the output shaft of the first main shaft drive motor 142 by a belt 148, and the first main shaft 138 is rotated by the first main shaft drive motor 142.

A second spindle 152 having a second spindle chuck 150 at its tip is supported on the second spindle stock 134 so as to be rotatable around its axis. Second spindle chuck 150
Is also a three-jaw chuck having the same center as the first spindle chuck 136, and the second spindle 152 is supported in a direction in which the second spindle chuck 150 is concentrically opposed to the first spindle chuck 136. .. The second main spindle 152 has a pulley 154 fixed to the rear end thereof and a second main spindle drive motor 1
The rotation of the second spindle drive motor 156 is transmitted to the output shaft of 56 by the fixed pulley 158 and the belt 160, and is rotated.

These first headstock 132 and second headstock 13
4, a first tailstock 164 and a second tailstock 166 are provided back to back with respect to each other. The first and second headstocks 132 of the column 130,
As shown in FIGS. 2 and 4, a support block 168 is fixed to the side surface to which the 134 is fixed, and the first and second tailstocks 164 and 166 are provided on the support block 168. These first and second tailstocks 164, 16
The configuration of 6 is the same, and the first tailstock 164 will be described in detail.

The main body 170 of the first tailstock 164 is mounted on the guide rail 172 of the support block 168 such that its position can be adjusted. The operator adjusts the distance from the first main shaft 138 and fixes the support block 168.

As shown in FIG. 5, a hydraulic cylinder 178 is integrally provided on the main body 170, and a piston rod 180 of the hydraulic cylinder 178 has a first center 182 concentrically and rotatably held by the first main shaft 138. The first hydraulic chamber 184 and the second hydraulic chamber 186 respectively formed before and after the piston 183 integrated with the rod 180 are selectively communicated with the pump and the tank, whereby the piston rod 180
Are moved forward and backward, and the first center 182 moves the first spindle 1
The first spindle 138 is moved toward and away from the first spindle 138 by moving on the axis of rotation of 38.

The second tailstock 166 is also constructed similarly to the first tailstock 164, and as shown in FIG.
A hydraulic cylinder 192 is provided integrally with a main body 190 movably attached to the shaft 68, and a second center 194 concentrically opposed to the second main shaft 152 is moved on the rotation axis of the second main shaft 152 to move the second main shaft 152. And move away from.

The door 4 provided on the partition wall 14
Reference numerals 4 and 46 are provided at positions corresponding to the first spindle 138 and the first center 182, and the second spindle 152 and the second center 194, respectively.

The first and second headstocks 132 of the column 130,
As shown in FIG. 1, the first Z-axis slide 200 and the second Z-axis slide 2 are provided on the upper portion of the side surface to which the 134 is fixed.
02 is movable in the Z-axis direction parallel to the rotation axes of the first and second main shafts 138 and 152. First and second Z
The shaft slides 200 and 202 are fixed to the column 130 and each pair of guide rails 204 extending in the Z-axis direction.
The column 130 is slidably supported by 206.
To the screw shafts 208, 210 attached to the nut 21.
2, 214 are screwed together.

The screw shaft 208 has a pulley 218 and a belt 22.
0, the pulley 221 (see FIG. 2) and the first Z-axis slide drive motor 222 rotate the first Z-axis slide 200 to the first spindle stock 132 and the first tailstock 164 of the column 130. Can be moved between. In addition, the screw shaft 210 is connected to the pulley 224 and the belt 22.
6, by being rotated by a pulley (not shown) and a second Z-axis slide drive motor 230,
The shaft slide 202 is moved between the second headstock 134 of the column 130 and the second tailstock 166.

First and second X-axis slides 236 and 238 are mounted on the first and second Z-axis slides 200 and 202 so as to be movable in the X-axis direction (vertical direction). The first and second X-axis slides 236 and 238 are slidably fitted to respective pairs of guide rails 240 and 242 provided on the first and second Z-axis slides 200 and 202, respectively. First and second Z-axis slides 200,
202 are screwed to screw shafts (not shown) supported by 202, and these screw shafts are respectively pulleys 244, 246, and
The first and second X-axis slides 236 and 238 are moved up and down by being rotated by the first and second X-axis slide drive motors 252 and 254 via the belts 248 and 250 and a pulley (not shown).

First and second turret tool rests 256 and 258 are attached to the first and second X-axis slides 236 and 238, respectively, facing the first and second headstocks 132 and 134, respectively. The turret turrets 256 and 258 have the same configuration, and the first turret turret 256 will be representatively described.

As shown in FIG. 2, the first turret tool post 256 is located on the first X-axis slide 236 in parallel with the rotation axis of the first spindle 138 and in the same vertical plane as the rotation axis. It is mounted rotatably around the axis of rotation. Four cutting tools 260 and 262 are attached to the first turret tool post 256 at equal angular intervals, and a total of eight cutting tools 260 and 262 are sequentially positioned at the use position (position directly below). , Z by the movement of the first Z-axis slide 200 and the first X-axis slide 236.
The work W is processed by being moved in the axial direction and the X-axis direction. 2 shows the first headstock 132 and tailstock 1.
64, Z-axis slide 200, X-axis slide 236, and turret tool post 256.

Further, the first headstock 132 and the second headstock 13
A chip unloading device 270 is provided between the chips 4 and 4. As shown in FIG. 1, the portion of the base 12 between the first and second headstocks 132 and 134 is inclined so as to approach each other right below the first and second headstock chucks 136 and 150. Chip collecting hole 27 having a wall surface
2 is provided in the collecting hole 272 thereof, as shown in FIG.
One end of No. 4 is arranged so that chips can be placed. The belt conveyor 274 is slanted upward from the rear end of the base 12, and is driven by the conveyor driving motor 276 at the upper end thereof, and the waste box 278 is installed on the lower side of the belt conveyor 274. The chips transported by 274 are accommodated.

Next, the operation will be described. At the start of processing, the work transfer robot 18 goes to the work supply device to pick up the work W and holds the work W by the first transfer chuck 56. The rotation of the rotation plate 52 causes the rotation arm 54 to rotate in a vertical plane parallel to the Z-axis direction, and the rotation of the wrist 60 causes the first transport chuck 56 to face downward. After moving to the work supply device, the first transfer chuck 56 holds the work W.

After gripping, the work transfer robot 18 moves to the vicinity of the first headstock 132. At this time, the rotation arm 52 is rotated in a vertical plane perpendicular to the Z-axis direction by the rotation of the rotation plate 52, and the first spindle chuck 136 grips the work W at the start of processing. If not, the rotation of the wrist 60 causes the first transport chuck 56 to face the first spindle chuck 136. If the work transfer robot 18 reaches the vicinity of the first headstock 132, the door 4
4 is opened, and after the work transfer robot 18 is stopped, the rotation arm 54 is rotated into the processing chamber 16 so that the axis of the first transfer chuck 56 and the axis of the first spindle chuck 136 coincide with each other. ..

At the start of processing, the first spindle chuck 13
If 6 does not grip the work W, the first spindle chuck 1
36 is open, the work transfer robot 18 moves to the small distance first spindle chuck 136 side, and the workpiece W is inserted into the first spindle chuck 136.

After the insertion, the center in the first spindle chuck 136 and the first center 182 of the first tailstock 164 are advanced and fitted into the center holes of both end faces of the work W,
While supporting both ends of the workpiece W, the first spindle chuck 136 is closed to grip the work W. Next, after the first transport chuck 56 is opened to release the work W,
The rotating arm 54 is rotated to move out of the processing chamber 16 and the processing is started.

The work W has a first headstock 132, a second headstock 132,
When the two types of processing are performed by 134 and the processing is performed in parallel, the work transfer robot 18
Receives the processed work W from the first spindle chuck 136, passes the unprocessed work W to the first spindle chuck 136, moves to the vicinity of the second spindle stock 134, and finishes the machining on the second spindle stock 134. After receiving the finished work W, the finished work W is delivered to the second spindle chuck 150 in the first headstock 132, but the machining is not performed in the second headstock 134 at the start of machining. Therefore, the work transfer robot 18 passes the work W to the first headstock 132 and then receives the work W from the work supply device.

After the work W is gripped by the first transfer chuck 56, the work W is moved to the vicinity of the first headstock 132. At this time, the empty second transfer chuck 58 receives the processed work W by the first transfer chuck 58. The rotation arm 54 is rotated into the processing chamber 16 so as to face the spindle chuck 136. At this time, the second transfer chuck 58 is open, the work transfer robot 18 moves to the small distance first spindle chuck 136 side, and the work W is moved to the second transfer chuck 5 by the second transfer chuck 5.
8, the second transport chuck 58 is closed and grips the work W, and then the grip of the work W by the first spindle chuck 136 is released, and the first spindle chuck 13 is released.
The center in 6 and the first center 182 are retracted, and further, the work transfer robot 18 moves in a direction away from the small distance first spindle chuck 136 to separate the work W from the first spindle chuck 136.

Then, after the wrist 60 is rotated 180 degrees and the first transport chuck 56 holding the unworked work W is opposed to the first spindle chuck 136, the first spindle chuck 136 and the first tailstock are pressed. The work W is delivered to the table 164.

The work transfer robot 18, which has transferred the work W to the first spindle chuck 136 and the first tailstock 164, moves to the second spindle stock 134, and the processed workpiece W is secondized in the first spindle stock 132. It is passed to the spindle chuck 150 and the second tailstock 166. In this case, when the work transfer robot 18 reaches the vicinity of the second headstock 134, the door 46 is opened. If machining is not performed on the second spindle stock 134, the second spindle chuck 150 is empty, and the second transport chuck 58 that holds the work W is the second spindle chuck 15.
The rotary arm 54 is rotated in a state of facing 0, moves into the processing chamber 16, moves the work transfer robot 18, moves the center of the second spindle chuck 150 and the second center 194, and moves the second center 194. After the work W is transferred to the second spindle chuck 150 by gripping the work W by the spindle chuck 150 and releasing the work W from the second transport chuck 58, the rotating arm 54 is withdrawn from the inside of the processing chamber 16 and the work is transported. The robot 18 again picks up the work W.

If the workpiece W has already been processed in the second headstock 134, the first headstock 132 is used.
When the work transfer robot 18 that has received the processed work W in (1) moves to the vicinity of the second spindle stock 134, the empty first transfer chuck 56 faces the second spindle chuck 150 when the rotating arm 54 rotates. The wrist 60 is rotated so that After the movement, the rotating arm 54 rotates to enter the processing chamber 16, and the first transfer chuck 56 receives the processed work W from the second spindle chuck 150 and the second tailstock 166. Then, after the wrist 60 is rotated by 180 degrees, the work W that has been processed by the first spindle stock 132 and gripped by the second transport chuck 58 is passed to the second spindle chuck 150 and the second tailstock 166. Be done. After passing the work W, the rotating arm 54 exits the processing chamber 16, and the work transfer robot 18 moves to the work ejecting device to pass the work W to eject it.

Thus, in the lathe of this embodiment, 2
Individual headstocks 132 and 134 are provided so as to face each other, a common chip carrying-out device 270 is provided, and one chip produced by processing in each of the first and second headstocks 132 and 134 is provided. The space between them can be shared, for example, by discharging by the carry-out device 270, and the lathe can be made compact and inexpensive.

Also, the first and second tailstocks 164, 166.
Are supported by a common support block 168, which can be easily installed, and can be collectively installed when maintenance unique to the tailstock is required. It is possible to obtain effects such as improvement in efficiency.

Further, the first and second headstocks 132 and 134
Is provided in the processing chamber 16 partitioned by the doors 44 and 46. If both the doors 24 and 26 and the doors 44 and 46 are closed, the first and second headstocks 132 and 134 are doubled. Therefore, noise and the like are significantly reduced, and if the doors 44 and 46 are closed, the work can be performed in the transfer chamber 20 during processing.

Further, in this lathe, since the column 130 is vertically installed on the base 10, even if the chips are scattered, the first and second Z-axis slides 200 and 202 and the X-axis slides are provided.
There is no accumulation on the running surface of the shaft slides 236, 238,
Their running is not hindered.

Furthermore, the first and second turret turrets 2
56 and 258 are first and second X-axis slides 2 provided on the front surface of a column 130 which is vertically installed on the base 10.
Since it is attached to 36,238, the doors 44,46
The operator can easily change the tool.

In the above embodiment, the tailstocks 164, 16 are provided for each of the two headstocks 132, 134.
Although 6 is provided, the tailstock may be provided only for one headstock.

The tailstocks 164 and 166 and the headstock 13 are also provided.
2,134, or instead of one of the tailstocks 164,166, the temporary holding described in the application of Japanese Patent Application No. 3-304157 or Japanese Patent Application No. 3-304158 relating to the present applicant. A chuck may be provided. If the temporary holding chuck is provided, as described in the specification of the above-mentioned application, the work transfer robot not only directly delivers the work to and from the main spindle chuck, but also delivers the work via the temporary holding chuck. It is possible to perform the processing, and by combining them, both ends of the work can be processed by one headstock. Further, if the work is passed to the temporary holding chuck when the spindle chuck cannot receive the work, the work transfer robot performs the next operation without waiting until the spindle chuck becomes ready to receive the work. Therefore, it is possible to improve the processing efficiency and diversify the processing modes.

Further, a work holder may be provided instead of the temporary holding chuck, and the work may be transferred between the spindle chuck and the work transfer robot via the work holder. For example, a work stand is provided between the headstock and the tailstock so as to be capable of moving up and down at a rising end position and a descending end position,
The work transfer robot places the work on the work stand at the rising end position, and after the spindle chuck grips the work, the work stand is retracted to the lower end position.

In addition, the present invention can be implemented in various modified and improved modes based on the knowledge of those skilled in the art without departing from the scope of the claims.

[Brief description of drawings]

FIG. 1 is a front view showing a lathe according to an embodiment of the present invention with a housing removed.

FIG. 2 is a side view (partial cross section) of the lathe.

FIG. 3 is a front view showing the appearance of the lathe.

FIG. 4 is a front view showing two tailstocks provided on the lathe.

FIG. 5 is a front view (partial cross section) showing one of the two tailstocks.

FIG. 6 is a front view (partial cross section) showing a transfer chuck provided in a work transfer robot that transfers a work to a headstock of the lathe.

7 is a sectional view taken along line VII-VII in FIG.

[Explanation of symbols]

 12 base 130 column 131 body frame 132 first spindle stock 134 second spindle stock 136 first spindle chuck 138 first spindle 150 second spindle chuck 152 second spindle 164 first tailstock 166 second tailstock 182 first Center 194 Second Center W Work

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Gen Ogawa, 19 Chasuyama, Yamamachi, Chiryu-shi, Aichi Fuji Machinery Co., Ltd.

Claims (1)

[Claims] 1. A main frame, a first headstock fixed to the main frame and having a first main spindle for holding and rotating a workpiece, and a first main spindle fixed to the main frame. And a second headstock having a second spindle that concentrically faces and rotates while holding a workpiece, and is provided at a position between the first headstock and the second headstock of the main body frame. And a tailstock having a center which is concentrically opposed to the first spindle and has a center movable on the rotation axis of the first spindle at its tip.