Device for feeding and discharging a work in an automatic hollow-pipe cutting apparatus

A device for feeding and discharging a work in an automatic hollow-pipe cutting apparatus comprises: a cutter device for cutting a hollow pipe; a cam lever driving mechanism for sending the hollow pipe to the cutter device; a fixed chuck device disposed near the cutter device; a movable chuck device disposed away from the cutter device; a movable die core disposed inside the cutter device and inside the hollow pipe; another cam lever driving mechanism for moving the movable chuck device; a stopper and ejector fitted to the fixed die core; whereby when the hollow pipe is fed to the cutter device, the fixed chuck device grasps and release the hollow pipe and the movable chuck device also grasps and release the hollow pipe but at timing different from grasping and releasing by the fixed chuck means and the feeding of the hollow pipe into the cutter device is performed by movement of the movable chuck device by means of the other cam lever driving mechanism, and after the hollow pipe is cut, during lowering of a slider which accommodate the stopper and ejector and a movable shearing cutter of the cutter device, the stopper and ejector is sent back by means of a cam in the direction reverse to the feeding direction of the hollow pipe into the cutter device so that a cut piece is discharged.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
The present invention relates to a device for feeding and discharging a 
work in an automatic hollow pipe cutting apparatus. 
2. Description of the Prior Art 
JP-A-3-19719 discloses a pipe shearing device. This known shearing device 
is provided with a fixed die core and a movable die core, these die cores 
being inserted into a pipe to be sheared. The movable die core is however 
loosely fitted in the pipe, and, therefore, the pipe is not clamped by the 
movable die core in the inside of the pipe and by the fixed die core in 
the outside of the pipe. Accordingly, the pipe is sheared in movable state 
and cannot be sheared precisely. 
JP-A-2-190211 discloses shearing blade mount for cut-off die set. This 
known shearing blade mount relates to a shearing blade assembly for use in 
a double cut die set of the type used to cut tubing continuously emanating 
from a pipe mill. This shearing blade assembly used in conjunction with 
the notching blade of the cut-off die set. This device includes a mounting 
block fixed to the upper platen of a die set, and a shearing blade mounted 
to a shearing blade carriage. The shearing blade cartridge is then 
inserted into the mounting block and is retained in a position by a am 
lock assembly. The cam lock assembly and carriage system allows the 
shearing blade to be quickly and effectively removed and replaced as 
needed. However, this shearing blade assembly does cut the pipe which is 
clamped in the outside of the pipe by two opposite jaws, but the pipe is 
not clamped in the inside of the pipe by a movable die core, therefore the 
pipe can not be cut undeformedly and precisely. 
SUMMARY OF THE INVENTION 
It is therefore an object of the present invention to eliminate such 
defects in the prior art. 
In order to attain the above object, according to an aspect of the present 
invention, a device for feeding and discharging a work in an automatic 
hollow-pipe cutting apparatus comprises: a cutter device for cutting a 
hollow pipe; a cam lever driving mechanism for sending the hollow pipe to 
the cutter device; a fixed chuck device disposed near the cutter device; a 
movable chuck device disposed away from the cutter device; a movable die 
core disposed inside the cutter device and inside the hollow pipe; another 
cam lever driving mechanism for moving the movable chuck device; a stopper 
and ejector fitted to the fixed die core; whereby when the hollow pipe is 
fed to the cutter device, the fixed chuck device grasps and release the 
hollow pipe and the movable chuck device also grasps and release the 
hollow pipe but at timing different from grasping and releasing by the 
fixed chuck means and the feeding of the hollow pipe into the cutter 
device is performed by movement of the movable chuck device by means of 
the other cam lever driving mechanism, and after the hollow pipe is cut, 
during lowering of a slider which accommodate the stopper and ejector and 
a movable shearing cutter of the cutter device, the stopper and ejector is 
sent back by means of a cam in the direction reverse to the feeding 
direction of the hollow pipe into the cutter device so that a cut piece is 
discharged.

DESCRIPTION OF THE PREFERRED EMBODIMENT 
A device for feeding and discharging a work in an automatic hollow pipe 
cutting apparatus according to the present invention will be described 
below on the basis of an embodiment illustrated in the accompanying 
drawings. 
Referring to FIGS. 1 to 3, a device for feeding and discharging a work in 
an automatic hollow pipe cutting apparatus according to the present 
invention is mounted on a base plate 1 of a not-shown machine carriage. A 
cam shaft 2 is rotatably supported by a pair of right and left brackets 3 
in the drawing so that the cam shaft 2 is continuously rotated by the 
rotation force transmitted trough a timing pulley 4 and a timing belt 5 
from a not-shown motor-driven main shaft. An elevation cam for driving the 
elevation of a slider 55 is supported by the cam shaft 2. The slider 55 
accommodates a movable shearing cutter 51 of a cutter device 50 for 
cutting a hollow pipe. A cam 6 for moving a movable chuck device 45, a cam 
8 for controlling a chuck opening/closing operation lever 18, and a cam 10 
for controlling a chuck opening/closing operation lever 12 are fixedly 
mounted on the cam shaft 2 in this order from the right to the left in 
FIG. 1. The cam 6 has a cam groove 7 in its circumference, the cam 8 has a 
cam face 9 which is in contact with a cam contact portion 19 of the chuck 
opening/closing operation lever 18 at its one end, and the cam 10 has a 
cam groove 11. The chuck opening/closing operation lever 12 is provided 
with a roller 14 rotatably fixed by means of a roller pin 13 on one end of 
the chuck opening/closing operation lever 12 so that the roller 14 is in 
contact with a cam face of the cam groove 11. The chuck opening/closing 
operation lever 12 is pivotally supported, by means of a pivot 15, on a 
chuck housing 31 of a fixed chuck device 30. A roller 17 is rotatably 
supported, by means of a roller pin 16, on the other end of the chuck 
opening/closing operation lever 12 so that the roller 17 is engaged into 
an operating groove 66, as shown in FIG. 3, of a chuck opening/closing cam 
42 of the fixed chuck device 30. The chuck opening/closing cam 42 is 
provided at its right end with a cam face like a truncated cone and is 
arranged so that the chuck opening/closing cam 42 per se moves, on a chuck 
device body 34, in the axial direction of a hollow pipe 48. Thus, when the 
chuck opening/closing operation lever 12 is turned by the chuck 
opening/closing operation lever controlling cam 10, the chuck 
opening/closing cam 42 moves, pawls 36 are pushed at their one ends so as 
to respectively turn around pins 37 fixed to the chuck device body 34, a 
sleeve 35 for chuck opening/closing operation is moved left in FIG. 3 by 
the other ends of the respective pawls 36, and an extension sleeve 33 of 
the fixed chuck device 30 is closed so that the hollow pipe 48 is 
immovably grasped in the vicinity of a movable die core 49. 
The chuck opening/closing operation lever 18 of the movable chuck device 45 
is pivotally supported by a pivot 20 on a chuck housing 31 of the movable 
chuck device 45. A roller 22 is rotatably pivoted by a roller pin 21 at 
the other end of the chuck opening/closing operation lever 18. Also in the 
movable chuck device 45, similarly to the fixed chuck device 30, the 
roller 22 is engaged into an operating groove 68, as shown in FIG. 3 of a 
chuck opening/closing cam 42. Accordingly, the chuck opening/closing 
operation lever 18 is urged through its cam contact portion 19 to turn 
around the pivot 20 by means of the cam 8 for controlling the chuck 
opening/closing operation lever 18, so that a chuck opening/closing cam 42 
is thereby moved in the axial direction of the hollow pipe 48 (shown in 
the upper half of FIG. 3), pawls 36 are turned around respective pins 37 
by means of the chuck opening/closing cam 42, a sleeve 35 for chuck 
opening/closing operation is moved left in FIG. 3 by the other ends of the 
respective pawls 36, and an extension sleeve 33 of the movable chuck 
device 45 is closed so that the hollow pipe 48 is grasped (shown in the 
upper half of FIG. 3). The grasping and release of the hollow pipe 48 by 
means of the extension sleeve 33 in the movable chuck device 45 are 
carried out in relation with but in timing different from the grasping and 
release of the hollow pipe 48 by means of the extension sleeve 33 in the 
fixed chuck device 30. That is, when the movable chuck device 45 has 
grasped the hollow pipe 48, the movable chuck device 45 moves toward the 
cutter device 50 while grasping the hollow pipe 48 and stops moving at a 
position where the left end of the hollow pipe 48 comes into contact with 
the right end of a stopper and ejector 56 as shown in FIG. 4. At that 
time, also the fixed chuck device 30 grasps the hollow pipe 48 and 
automatic cutting of the hollow pipe 48 is carried out by means of the 
cutter device 50. After automatic cutting of the hollow pipe 48, the fixed 
chuck device 30 releases the hollow pipe 48, and also the movable chuck 
device 45 releases the hollow pipe 48 and retreats from the cutter device 
50 in the direction opposite to the feeding direction of the hollow pipe 
48 (rightward in FIG. 2). The movable chuck device 45 grasps the hollow 
pipe 48 again in the retreated position, and the next work feeding cycle 
is started. 
A roller 25 pivoted, by a roller pin 24, on one end of an operation lever 
23 for moving the movable chuck device 45 is engaged into the cam groove 7 
of the cam 6 for moving the movable chuck device 45. The operation lever 
23 for moving the movable chuck device 45 is pivotally supported, by means 
of a pivot 26, on the base plate 1. A roller 28 is rotatably supported, by 
means of a roller pin 27, on the other end of the operation lever 23 for 
moving the movable chuck device 45 so that the roller 28 is engaged into 
an operation groove 46 formed in the housing 31 of the movable chuck 
device 45. Thus, the operation lever 23 is turned by the rotation of the 
cam 6 so that the movable chuck device 45 is made to perform reciprocating 
movement in the axial direction of the hollow pipe 48. When the movable 
chuck device 45 moves forward and moves backward, the cam contact portion 
19 of the chuck opening/closing operation lever 18 slides on the cam face 
9 of the cam 8 for controlling the chuck opening/closing operation lever 
18 while contacting with the cam face 9. In this case, since the cam face 
9 is formed so that it has the same contour in any position in the axial 
direction of the cam shaft 2, the turning operation of the chuck 
opening/closing operation lever 18 is not influenced by the movement of 
the movable chuck device 45 but it is controlled only by the cam diagram 
of the cam face 9 of the cam 8 for controlling the chuck opening/closing 
operation lever 18, regardless of the state of the movable chuck device 45 
as to whether the movable chuck device 45 is moving or not. 
When the hollow pipe 48 is being cut, the forward end of the hollow pipe 48 
is pressed against the end surface of the stopper and ejector 56, and, in 
the inside of the hollow pipe 48, the end of a fixed die core 60 which is 
fitted into the hollow pipe 48 by a predetermined size is in contact with 
the forward end of a movable die core 49 which is fitted into the hollow 
pipe 48 by a predetermined size so that the position of the hollow pipe 48 
is immovably grasped during the cutting operation. Accordingly, accurate 
cutting of the hollow pipe 48 is ensured in the axial direction as well as 
in the radial direction and the length, the external form and the inside 
diameter of a cut piece is ensured with predetermined accuracy. 
After the hollow pipe 48 is cut, during lowering of the slider 55 which 
accommodate the movable shearing cutter 51 of the cutter device 50 and the 
stopper and ejector 56 fitted to fixed die core 60, a cut piece 48' is 
discharged from the fixed die core 60 by the stopper and ejector 56 by the 
mutual movement between a grooved cam 63 for the stopper and ejector 56 
and a grooved cam 64 for the fixed die core 60. 
Further, the reference numeral 32 designates an adjusting ring which is 
fixed to the extension sleeve 33. The adjusting ring 32 cooperates with 
the extension sleeve 33 so as to clamp the pipe 48 to be cut. The 
reference numeral 38 designates a bracket provided with the pins 37 which 
bear the pawls swingably. The reference numerals 40 and 41 designate nuts 
which are used to secure the bracket 38 to the chuck device housing 31 and 
to secure the body 34 to the chuck device, respectively. 
The reference numerals 47, 47', and 47" designate guides for movable chuck 
device 45, the guides being arranged on the base plate 1 so as to guide 
the movable chuck device 45 in the longitudinal direction. 
The reference numeral 52 designates a fixed shearing cutter fixed to a 
support 53 for supporting the fixed shearing cutter 52. The fixed shearing 
cutter 52 cooperates with the movable shearing cutter 51 to cut the pipe 
48 under application of shearing force between the cutters 51 and 52. 
The reference numeral 57 designates a bracket to which the stopper and 
ejector 56 is fixed. The stopper and ejector 56 is used to stop the 
feeding of the pipe 48 in the longitudinal direction and is used to eject 
the cut piece 48' outside the cutting apparatus after cutting operation. 
The reference numeral 59 designates a roller rotatably supported on a 
roller pin 58 which is secured to the bracket 57. The roller 59 is engaged 
with the groove of the grooved cam 63 for the stopper and ejector 56. The 
reference numeral 62 designates a roller rotatably supported on a roller 
pin 61 which is secured to the fixed die core 60 across its longitudinal 
axis. The roller 62 is engaged with the groove of the grooved cam 64 for 
the fixed die core 60. 
According to the present invention, the work feeding/discharging can be 
carried out rapidly and accurately. The work can be worked with 
predetermined preciseness in its length, and inner and outer diameters. 
Further, no burr or no injury is produced in the work and therefore no 
additional working step to eliminate such defects.