JPH0248366B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field The present application relates to a chuck pawl used when automatically replacing chuck pawls, and is intended to ensure and easily replace chuck pawls with a simple structure.

Prior Art and Problems As the automation of machine tools progresses, automatic chuck pawl exchange has become essential, and various types of chuck pawl automatic exchange devices are in use. For example, JP-A-55-
No. 70507 shows a chuck pawl changing device for a machine tool having a swivel carriage and a cross slide rest. According to this, the claw has a recess (or groove) formed on its gripping side. Such a chuck is equipped with a chuck that is equipped with a pawl storage magazine, a pawl exchange device, etc., and is moved between a non-exchangeable device that is remote from the chuck and a forward end position above the chuck that protrudes from the machine base. When used in an automatic chuck pawl changing device, the amount of protrusion from the machine base of the automatic chuck pawl changing device increases at the forward end position, making it unstable.

Purpose and Summary In view of the above-mentioned drawbacks of the conventional technology, the present application has a simple structure by providing a locking portion toward the back side of the chuck pawl and allowing the pawl changing device to be engaged and removed from the locking portion. The purpose of this invention is to make it possible to perform reliable nail replacement, and to downsize the entire device, which has a limited installation space.

Embodiment Next, an embodiment of the present application will be described in detail based on the drawings. As is well known, the chuck claw is the chuck body 6.
radial sliding groove 10 (3 in the drawing) formed in
A slider member 12 (master jaw) slidably fitted in a base jaw 2 shown in FIG.
13 and the top jaw 213a shown in FIG. Since both are to be replaced, in the explanation of this application, the two fixed together are replaced with one nail.
It is called 3.

The claw 13 of the present invention is constructed as follows. 14 is a locking part for replacing the claw;
The rising part 15 of the edge of No. 3 (upper edge in the drawing)
A locking groove 16 is provided which opens toward the back side of the claw 13 and is open on both sides (upper and lower sides in FIG. 10-1) without any barrier.

An automatic chuck pawl changing device 4 using the pawl 13 having the locking portion 14 as described above will be described in detail below.
Nail replacement is performed by. 1 is a well-known machine tool such as an NC lathe, 2 is the machine base, and 3 is the main spindle.
An automatic chuck pawl changing device 4 is attached to this machine tool. Next, this automatic chuck pawl changing device 4 will be explained. Reference numeral 5 denotes a quick change chuck, and the chuck main body 6 is integrally attached to the front end of the main shaft 3. As shown in FIG. 2, a wedge piece 7 is fitted into the center of the chuck body 6 so as to be slidable in the direction of the rotational axis of the chuck body 6. This wedge piece 7 is connected by a bolt 9 to a drawbar (not shown) which is connected to a piston rod of a rotating cylinder 8 attached to the rear end of the main shaft 3. Also, radial sliding grooves 10, 1 formed in the chuck body 6
1 includes the slide member 12 and the sliding portion 13 of the claw 13.
a are fitted so as to be slidable in the radial direction, and a wedge portion 12a having a T-shaped cross section formed at the center of the slider member 12 has a T-shaped cross section formed on the wedge piece 7.
It is fitted into the wedge-shaped groove 7a. Furthermore, a positioning hole 12b for positioning is formed on the outer periphery of the slide member 12, as shown in FIG.

17 is a latch tooth provided on the back side of the claw 13;
This rack tooth 17 can be engaged with and disengaged from the slide member 12 by a claw engaging device 18, which will be described below. This pawl engagement device 18 includes a meshing member 19 that is fitted into the sliding member 12 so as to be slidable only in the front-rear direction, and an engaging member 19 that is fitted inside the sliding member 12 so as to be able to move only in the radial direction. It is equipped with an operation pin 20. The front surface of this meshing member 19 has a rack tooth 2.
1 is formed, and this lock tooth 21 acts as a biasing spring 22.
It is adapted to be engaged with the lock teeth 17 of the pawl 13 by the force of the spring. In addition, the above-mentioned meshing member 1
9 and the operation pin 20 are engaged with each other by engagement surfaces inclined with respect to the sliding direction, and the operation pin 2
0 is pushed in from the outer circumferential side and moved toward the center of the chuck body 6, the engaging member 19 slides backward against the biasing spring 22, and the rack teeth 21 are moved to a position where they do not engage with the rack teeth 17. , operation pin 20
When the mesh member 19 is moved back to its original position, the engaging member 19 is slid forward by the biasing spring 22 and the lock tooth 2 is moved.
1 to a position where it engages with the rack teeth 17. A set pin 23 is fitted into the meshing member 19 so as to be slidable in the front-rear direction, and this set pin 23 is urged forward by a spring 24 and is prevented from coming out by a pin 25. The tip of 23 is the easy tooth 1 of the claw 13
7. The quick change chuck 5 configured as described above is connected to the chuck main body 6 by the action of an NC device (not shown).
The sliding groove 11 is indexed to a predetermined pawl exchange position A (the figure shows the case above the rotation center, but any position such as diagonally above, lateral, or below the rotation center may be used). It is configured so that it can be stopped.

Next, 28 is a guide part in the front-rear direction (horizontal direction in FIG. 2) formed on the upper part of the machine base 2, and 29 is a table fitted to this guide part 28 so as to be slidable in the front-rear direction. Forward and backward motion cylinder 3 fixed on stand 2
0 longitudinal piston rods are connected. Also, a stopper bolt 3 is attached to the table 29.
1 are screwed together so as to be adjustable back and forth and are fixed by a lock nut 32, and the tip of this stopper bolt 31 abuts on a contact portion 33 formed on the machine base 2 to position the forward end of the table 29. It's becoming like that. The head side end of the cylinder body 34a of the lifting cylinder 34 is fixed onto the table 29 with a mounting bolt 35, and its piston rod 34b is directed upward. The cylinder body 34a of the lifting cylinder 34 is composed of a tube member 36a and a lid member 36b.
A supply and discharge pipe 37 that protrudes into the tube member 36a is fixed to the center of the tube member 6b, and this supply and discharge pipe 37 is inserted into the insertion hole 3 of the piston 34c and the piston rod 34b.
It is inserted into 8. This supply/discharge pipe 37 is formed with a supply/discharge hole 40 for supplying and discharging pressure oil to the upper piston chamber through the communication hole 39, and the lid member 36b is formed with a supply/discharge hole 40 for supplying and discharging pressure oil to the lower piston chamber. Supply/discharge hole 41
is formed. A display shaft 42 having a dog 42a is implanted on the upper end surface of the tube member 36a, and this display shaft 42 projects through an elevator frame to be described later. Further, a sliding hole 44 formed in the shaft portion 43a of a shaft member 43 is fitted onto the outer periphery of the tube member 36a so as to be vertically slidable while being prevented from rotating by a key 45. Part 43a
The tip of the piston rod 34b is connected to the upper end. A support frame 46 is integrally attached to the shaft portion 43a of this shaft member 43, and this support frame 46
and the shaft member 43 constitute an elevating frame 47. Limit switches 48 and 49 are attached to the support frame 46 above the shaft member 43, respectively.
One of the limit switches 48 detects the dog 42a of the display shaft 42 when the lifting frame 47 is raised to the highest level by the lifting cylinder 34, and the other limit switch 49 detects the dog 42a of the display shaft 42.
7 is lowered to the lowest position, the tube member 36a
The upper end surface of the sensor is detected via a detection rod 49a. The mounting shaft portion 49b of the limit switch 49 is screwed onto the lifting frame 47 so as to be vertically adjustable, and is fixed by a lock nut 49c.
The lower end of this mounting shaft portion 49b is the tube member 36a.
The lower end of the elevating frame 47 is positioned by contacting the upper end of the elevating frame 47.

Next, 50 is the quick change check 5 mentioned above.
This is a nail storage magazine for storing a large number of replacement nails 13 for replacing the nails 13 of the present invention. In this claw storage magazine 50, 51 is a rotating body having a circular planar shape, and a hole 52 formed in the center thereof is rotatably fitted into the shaft portion 43a of the shaft member 43. The axis of rotation of this rotating body 51 is set to be parallel to the sliding direction of the sliding groove 11 at the pawl exchange position A in the quick change chuck 5. The outer periphery of the rotating body 51 has the sliding groove 1
1, a large number of holders 53 capable of holding the sliding portion 13a of the claw 13 that can be fitted in
are provided at equal intervals. This holder 53 locks and holds the pawl 13 fitted in the vertical holding groove 54 formed on the outer periphery of the rotating body 51 so that the sliding portion 13a of the pawl 13 can fit therein. It is composed of a holder 55. This retainer 55 is composed of two locking pins 55a that are embedded in the bottom of the retaining groove 54 so as to be freely protruding and retractable, are urged in the projecting direction by a spring 56, and are prevented from coming off by a pin 57. However, it may also be composed of a gripping piece or the like that is moved by a cylinder or the like. The tips of these locking pins 55a are formed in a chevron shape when viewed from the side, similar to the set pin 23 of the quick change chuck 5, and when the pawl 13 is inserted into or removed from the holding groove 54, the lock teeth 17 of the pawl 13 It's starting to get pushed in. The above-mentioned holding groove 54
The sliding part 13a of the replacement claw 13 is fitted into the
It is locked and held by a locking pin 55a. A gear 58 is formed on the rotating body 51, and a driving gear 60 attached to a rotating shaft 59a of a motor 59 fixed to the support frame 46 is meshed with the gear 58. Dogs 61 and 62 are fixed to the lower side of the rotating body 51 in correspondence with the husband's holder 53, and a limit switch 63 for deceleration detects one dog 61 and a stop switch 63 detects the other dog 62. A limit switch 64 and a limit switch 64 are sequentially attached to the lower end of the shaft member 43.

When the limit switch 63 detects the dog 61, the motor 59 is switched to decelerated rotation, and when the limit switch 64 detects the dog 62, the motor 59 is switched to a decelerated rotation mode.
9 is stopped, thereby each holder 53
The holding groove 54 is located on the extension line of the sliding groove 11 at the pawl exchange position A when the table 29 is located at the forward end and the lifting frame 47 is located at the lower end (hereinafter referred to as the replacement preparation state). It is designed to index and stop at a predetermined pawl exchange position B.

Next, 65 is an exchange device for exchanging the pawls 13 from the sliding groove 11 at the pawl exchange position A to the holder 53 at the pawl exchange position B, or from this holder 53 to the sliding groove 11, respectively. It is composed of a guide block 66 and a pawl moving device 67 as shown. The guide block 66 is connected to the shaft member 43.
is fixed to the lower end of the This guide block 66 has these sliding grooves 11 and holding grooves 54 in a portion located between the sliding groove 11 at the pawl exchange position A and the holder 53 at the pawl exchange position B in the replacement preparation state. Guide groove 6 substantially continuous in a straight line
8 is formed. This guide groove 68 is similar to the sliding groove 11 and the holding groove 54 in the sliding part 1 of the claw 13.
3a is formed in a cross-sectional shape capable of guiding the upper part,
The lower end portion is formed to be slightly wider toward the tip so that the claw 13 can be easily guided into the guide groove 68. The guide groove 68 is preferably set to have at least the same length as the sliding portion 13a of the claw 13 so that the sliding portion 13a of the claw 13 can be stably guided over approximately the entire length. Next, in the claw moving device 67,
Reference numeral 69 denotes a moving cylinder fixed to the support frame 46, and its piston rod 70 is positioned above the holder 53 at the pawl exchange position B so as to protrude downward. This piston rod 7
A movable body 71 is fixed to the tip of the movable body 71, and a locking piece 74 and an operating piece 7 are inserted into two guide grooves 72 and 73 in the front and rear directions formed on this movable body 71 as shown in FIG.
5 are fitted together so as to be movable in the front and rear directions.
Both ends of a link 76 whose intermediate portion is pivotally connected to the movable body 71 are connected to the locking piece 74 and the operation piece 75 by pins, respectively. Further, the operating piece 75 is biased rearward by a spring 77 that is pressurized between it and the movable body 75, and is prevented from coming out by the stop portion 74b of the locking piece 74 coming into contact with the movable body 71. and
Normally, the operating part 75a of the operating piece 75 projects rearward, and the engaging part 74a of the locking piece 74 projects forward.
The engaging portion 74a of the locking piece 74 is connected to the piston rod 7 of the moving cylinder 69 in the replacement preparation state.
When 0 is moved to the lowest position, the claw replacement position A
, or the locking groove 16 of the pawl 13 fitted into the chuck body 6, and when the piston rod 70 is moved to the uppermost end, the pawl at the pawl exchange position B, that is, the locking of the pawl 13 held in the holder 53. The grooves 16 are positioned so that they can be engaged with and detached from the grooves 16, respectively.
Further, the operating portion 75a of the operating piece 75 is connected to the holding groove 5.
4 and a passage groove 7 formed at the bottom of the guide groove 68.
8,79.
An operation guide piece 80 is disposed within the passage groove 79 of the guide block 66 and is held by the guide block 66 so as to be movable in the front-rear direction. This operation guide piece 80 is adapted to be moved back and forth by a claw release cylinder which will be described later. When the piston rod 70 of the claw moving cylinder 69 is lowered, the operation guide piece 80 is moved to the forward end as shown in FIG. Connect piece 75 to spring 7
7 and move it forward against the locking piece 7.
4 to the rear so as to escape from the locking groove 16 of the pawl 13 at the pawl exchange position A, and
When the piston rod 70 is located at the lower end, it is moved to the backward end as shown in FIG. It enters into the locking groove 16 of the pawl 13 at the pawl exchange position A from the rear side and engages therewith. Note that the operation section 75
It is also possible to configure a with a pin, and to form a guide groove in the operation guide piece 80 to guide the pin, so that the operation guide piece 80 forcibly moves the operation piece 75 back and forth. The moving body 71 also has a stopper shaft 1.
00 is screwed on, and this stopper shaft 100 is inserted through a hole 101 formed in the flange portion 69a of the moving cylinder 69. Nuts 102 and 103 for positioning the lower end and the upper end of the piston rod 70 are screwed onto the stopper shaft 100, respectively.

Next, 81 is the quick change check 5.
By operating the claw engaging position 18 of the slider member 12 and the claw 1,
This is a claw release device for disengaging from the engagement with 3.
In this claw removing device 81, 82 is a claw removing cylinder, and a piston 82b is fitted in a piston chamber 82a formed in the guide block 66 so as to be movable up and down.
It is constructed by connecting. This declawing cylinder 82 also serves as a positioning cylinder, and its piston rod 84 is directed approximately toward the center of the chuck. A mounting piece 85 is fixed to the piston rod 84, and a hollow cylindrical pressing pin 86 is protruded from the mounting piece 85 as shown in FIG. This pressing pin 86 is positioned so as to face the end surface of the operating pin 20 of the claw 13 at the claw replacing position A in the replacement preparation state, and when the piston rod 84 of the claw removing cylinder 82 is moved to the lower end, the operating pin 20 is moved toward the center of the chuck so that the lock teeth 21 of the meshing member 19 are aligned with the rack teeth 1 of the pawl 13.
7 to a rear position where it does not engage. Furthermore, as shown in FIG. 7, a positioning pin 87 for positioning the claw 13 at the claw replacement position A is provided on the mounting piece 85 in a protruding manner. This positioning pin 87 is in the claw replacement position A in the replacement preparation state.
When the piston rod 84 is moved to the lower end, the positioning pin 87 is fitted into the positioning hole 12b and the pawl 13 is placed at a predetermined index position. It is designed for positioning. The positioning pin 87 and the positioning hole 12b together with the claw release cylinder 82 constitute a positioning device. Further, as shown in FIG. 3, a display rod 88 is fixed to the mounting piece 85, and the dogs 89 and 90 fixed to the display rod 88 operate a limit switch (not shown) fixed to the guide block 66. on the piston rod 84 by
The bottom edge can be detected. A guide block 66 is provided in the hollow hole 86a of the pressing pin 86.
A guide tube 91 fixed to the press pin 8 is inserted into the press pin 8.
6 and the positioning pin 87 are prevented from rotating about the piston rod 84. Furthermore, an inclined groove 92 having a T-shaped cross section is formed in the mounting piece 85, and the inclined groove 92 has a T-shaped cross section formed at the rear end of the operation guide piece 80.
A letter-shaped inclined portion 93 is fitted.

Next, reference numeral 94 is an engagement confirmation device for detecting whether the return movement of the operating pin 20 has been reliably performed when the pushing of the operating pin 20 by the claw removing device 81 is released; Pipe hole 91a
It is constituted by a proximity switch 95 provided inside. The proximity switch 95 can detect the operating pin 20 when the operating pin 20 is located at the return position in the replacement preparation state, but when the operating pin 20 is pushed by the pressing pin 86, the operating pin 20 is detected. The position is set so that it cannot be detected. Note that 96 is a cover attached to the front end of the support frame 46, and a proximity switch 9 is provided at the lower end for detecting the presence of the claw 13 at the claw replacement position A.
7 is installed. Further, a proximity switch 98 is attached to the front end of the shaft member 43 for detecting the presence of the claw 13 at the claw replacement position B.

Next, in the machine tool 1 having the above configuration, the claw 13 of the quick change chuck 5 is inserted into the claw storage magazine 5.
The operation when replacing the pawl 13 with the No. 0 pawl 13 will be explained. First, when a command to change the jaws is sent from a separate command device due to a change in the workpiece, etc., the rotation of the spindle 3 is stopped in response to the command, and one of the jaws 13 is moved to a predetermined position for changing the jaws. Allocate to A. The rotating cylinder 8 also moves the wedge piece 7 forward and moves the three pawls 13 of the quick change chuck 5 to the open position. Next, the longitudinal cylinder 30 is operated to move the table 29 to the forward end as shown in FIG. 2, and the lifting cylinder 34 is operated to lower the lifting frame 47 to the lowering end. This table 29
The forward end of the lifting frame 47 and the lowering end of the lifting frame 47 are accurately positioned by the action of the stopper bolt 31 and the mounting shaft portion 49b, so that one of the holders 53 of the claw storage magazine 50 is accurately positioned at the claw exchange position B. The guide groove 68 of the guide block 66 is aligned with the sliding groove 11 of the pawl 13 at the pawl exchange position A and the pawl exchange position B.
It is accurately positioned between the holding groove 54 of the holder 53 so as to be substantially continuous with them in a straight line, and is ready for replacement. Note that the rotating body 51 of the claw storage magazine 50 is indexed and rotated in advance by the motor 59, and the rotating body 51 of the claw storage magazine 50 is indexed and rotated in advance to reach the claw replacement position A when the chuck is removed from the chuck body 6.
An empty holder 53 for storing the claws 13 is indexed to the claw replacement position B. The empty holder 53 in the claw storage magazine 50 may be indexed after the longitudinal movement cylinder 30 and the elevating cylinder 34 are operated. Next, the moving cylinder 69 of the claw moving device 67 is activated to lower the moving body 71. In this case, the claw removing device 8
As shown in FIGS. 2 and 5, the claw removing cylinder 82 of No. 1 is maintained with its piston 82b at the rising end,
An operation guide piece 80 disposed within the passage groove 79 of the guide block 66 is made to protrude forward.
Therefore, when the movable body 71 is lowered as described above, the operating portion 75 of the operating piece 75 is moved as shown in FIG.
a is engaged with the operation guide piece 80 and moved forward, whereby the locking piece 74 is moved rearward and the engaging portion 74a and the protruding portion 15 of the claw 13 at the claw exchange position A are moved.
When the movable body 71 is positioned at the lower end, the engaging portion 74a faces the locking groove 16 of the pawl 13 at the pawl exchange position A in a manner capable of engaging with the locking groove 16.
Next, the claw removing cylinder 82 of the claw removing device 81 is operated to lower the mounting piece 85, whereby the pressing pin 86 pushes the operating pin 20 of the claw engaging device 18 toward the center of the chuck, and the engaging member 19 is moved into position. 6, as shown in FIG.
1 and the lock teeth 17 of the pawl 13 are disengaged. Note that even if the engagement between the rack teeth 21 and the rack teeth 17 is disengaged as described above, the set pin 23 remains engaged with the rack teeth 17 of the pawl 13 by the force of the spring 24, so that the pawl replacement position A is maintained. The pawl 13 is in the sliding groove 11
This will prevent it from falling out. Further, as the mounting piece 85 is lowered, the positioning pin 87 is fitted into the positioning hole 12b of the sliding member 12 as shown in FIG. and guide groove 6
8 and the sliding groove 11 at the pawl exchange position A are accurately opposed to each other. Further, when the mounting piece 85 is lowered as described above, the operation guide piece 80 is moved rearward, whereby the operation piece 75 of the pawl moving device 67 is moved rearward by the spring 77, and the locking piece 74 is moved backward. is moved forward, and its locking portion 74a engages with the locking groove 16 of the pawl 13 at the pawl exchange position A. Next, the moving cylinder 69 is operated to raise the movable body 71, whereby the engaging portion 74a of the locking piece 74 is hooked on the locking groove 16 of the pawl 13 at the pawl exchange position A.
Raise it by pulling it up. Therefore, the pawl 13 at the pawl exchange position A is inserted into the sliding groove 1 as shown in FIG.
1, it is guided by the guide groove 68 and fitted into the holding groove 54 at the pawl exchange position B, and is held in place by the locking pin 55a while being fitted in the holding groove 54. . Next, the motor 59 is operated to index and rotate the rotating body 51 of the claw storage magazine 50, and the empty holder 53 for storing the next claw 13 of the quick change chuck 5 is moved to the claw exchange position B. However, when the rotating body 51 of the claw storage magazine 50 rotates in this way, the claw 13 that was first pulled out from the quick change chuck 5 and held in the holding groove 54 of the holder 53 also rotates one pitch. This rotation automatically disengages the engagement portion 74a from the engagement groove 16. As described above, since there are no barriers on both sides of the locking groove 16 that would impede rotation, the rotation of the rotating body 51 and the release of the engagement between the engaging portion 74a and the engaging groove 16 are performed smoothly. Further, the claw release cylinder 81 operates to raise the mounting piece 85, and thereby the pressing pin 86 is moved to the operating pin 2.
0 is released, and the positioning pin 87 is removed from the positioning hole 12b. When the pressing pin 86 releases the pressing of the operating pin 20 as described above, the engaging member 19 of the claw engaging device 18 is moved back forward by the biasing spring 22, and at the same time, the operating pin 20 is moved toward the outer circumferential side of the chuck. Moved back. In this case, the proximity switch 95 of the engagement confirmation device 94 is
0 is detected to confirm whether the operation pin 20 has been completely returned to its original position, and based on this confirmation signal, the quick change chuck 5 is indexed and rotated again to move the next pawl 13. The sliding groove 11 is indexed to the pawl replacement position A. Thereafter, the above operation is repeated to hold the three claws 13 of the quick change chuck 5 in the holder 53 of the claw storage magazine 50. After the third pawl 13 is held in the pawl storage magazine 50 as described above, the pawl removal cylinder 81 operates to raise the mounting piece 85, and when the proximity switch 95 detects the operating pin 20, Index and rotate the quick change chuck 5 to return the sliding groove 11 of the first removed pawl 13 to the pawl replacement position A.
At the same time, the motor 59 rotates the rotating body 51 of the claw storage magazine 50 to move the holder 53 holding the replacement claw 13 to be fitted into the sliding groove 11 at the claw replacement position A to the claw replacement position. I divide it into B, but
As is clear from the above explanation, since the movable body 71 only moves up and down in the drawing, the rotary body 51 of the claw storage magazine 50 rotates to move the replacement claw 13 to the claw replacement position as described above. By indexing, the engaging portion 74a of the pawl moving device 67 automatically enters the locking groove 16 of the pawl 13, and the two engage with each other.
As in the case described above, this engagement operation is performed smoothly. Next, the claw release cylinder 82 is actuated to lower the mounting piece 85, which causes the pressing pin 86 to push the operating pin 20 again into the engaging member 1.
9 is moved backward, and the positioning pin 87 is inserted into the positioning hole 1.
2b to determine the relative position of the guide block 66 and the chuck body 6. Next, the moving cylinder 69 is operated to lower the movable body 71, whereby the replacement claw 13 held in the holder 53 at the claw replacement position B is attached to the locking piece 74 as shown in FIG. Therefore, after being pushed out from the holding groove 54, it is guided to the guide groove 68 and fitted into the sliding groove 11 at the pawl exchange position A, and is locked by the set pin 23 while being fitted into the sliding groove 11. Retained.
The claw 13 fitted into the holding groove 54 as described above
When fitting into the sliding groove 11, the pawl 13 is guided by the guide groove 68 to correct the position of the pawl 13, so that the pawl 13 can be surely fitted into the sliding groove 11. Can be done. Further, when the movable body 71 is lowered as described above, the claw removing cylinder 8
2 lowers the mounting piece 85 and moves the operation guide piece 80 backward, so the operation part 75a of the operation piece 75 is not pushed forward by the operation guide piece 80, and the locking piece 74 The locking part 74a is the claw 1
It will not come off from the locking groove 16 of No.3. Next, the claw release cylinder 82 is actuated to raise the mounting piece 85, whereby the pressing pin 86 releases the pressing of the operation pin 20, and the positioning pin 87 moves into the positioning hole 1.
Leaves 2b. Accordingly, the engaging member 19 of the pawl engaging device 18 is moved back forward by the biasing spring 22 so that its own rack teeth 21 are engaged with the rack teeth 17 of the pawl 13 at the pawl exchange position A, and the operation is resumed. pin 2
0 is moved back toward the outer circumference of the chuck. In this case, if the lock teeth 21 of the meshing member 19 are reliably engaged with the rack teeth 17 of the pawl 13, the operating pin 20 is completely moved back, and the operating pin 20 can be detected by the proximity switch 95. If the engagement between the rack teeth 21 and the rack teeth 17 is uncertain for some reason, the return movement of the operating pin 20 will be incomplete, and the operating pin 20 may not be detected by the proximity switch 95. Easy to lose teeth 21,
17 is uncertain. When the mounting piece 85 is raised by the claw removing cylinder 82 as described above, the operation guide piece 80 is moved forward, and the engaging portion 74a of the locking piece 74 and the locking groove 1 of the claw 13 are moved forward.
6 is released. Next, the moving cylinder 6
9 operates to move the moving body 71 to the rising end.
Thereafter, the quick change chuck 5 is indexed and rotated to index the sliding groove 11 of the second removed pawl 13 to the pawl replacement position A, and the motor 59
Holder 5 holds a replacement pawl 13 to be fitted into the sliding groove 11 at the pawl replacement position A by rotating the pawl 1.
3 to the claw replacement position B. When the holder 53 holding the claw 13 is indexed to the claw replacement position B, the engaging portion 74 of the locking piece 74 is moved in the same manner as described above.
a automatically fits into the locking groove 16 of the claw 13. Thereafter, in the same manner as above, insert the claw storage magazine 50 into the three sliding grooves 11 of the quick change chuck 5.
Insert the claw 13. The third claw 13 is fitted into the sliding groove 11 as described above, and then the moving body 71
After the attachment piece 85 is raised, the motor 59 rotates the rotating body 51 to index the empty holder 53 at the position where the claw 13 was first removed to the claw replacement position B in preparation for the next claw replacement. let Thereafter, the lifting cylinder 34 is activated to raise the lifting frame 47, and the forward/backward movement cylinder 30 is activated to move the table 29 rearward, thereby moving the claw storage magazine 50 and changing device 65 from the quick change chuck 5. It is moved to a distant non-exchange position, completing a series of claw exchange operations.

Other Embodiments Next, other embodiments of the present application will be described with reference to the drawings. The embodiment shown in FIG. 12 and FIG. 12-1 is
A locking portion 14 is provided on the back side of the base jaw 213 and positioned above the engraved surface of the rack 17.
By doing this, the position of the locking part 14 is closer to the back side of the claw 13 than in the first embodiment.
There is an advantage that the chuck pawl changing device 4 can be made smaller accordingly.

Further, in the embodiment shown in FIG. 13 and FIG. 13-1, two projecting pieces 16a are provided protruding from the back side of the upright part 15 constructed on the upper edge of the base jaw 213, as in the first embodiment. This operates in the same way as the first embodiment. Note that all of the embodiments shown in the drawings are based on the claw 1.
3, the locking portion 14 is provided only on the upper end side of the hook 1.
Reverse 3 by 180 degrees, that is, reverse the top and bottom of claw 13, and turn 1
In the book claw 13 that is compatible with two types of gripping diameters, the object of the present application is achieved by providing the locking portions 14 on both the upper and lower sides of the claw 13. Furthermore, in this embodiment, the locking groove 16 and the engaging portion 7 at the pawl exchange position A are
Although the engagement and disengagement with 4a is performed in conjunction with the operation of the claw release cylinder 82, the present invention is not limited to this, and any configuration may be used as long as the two can be engaged and disengaged when desired. .

Effects As detailed above, the chuck pawl in the present application has a locking part facing the back side at its upper end or both upper and lower edges, and the chuck changing device of the automatic chuck pawl changing device is locked to this locking part. Since the claws can be replaced by removing the claws and moving the claws, the claw changing device can be moved to the center of the claw changing device, and the claw changing device can be moved to the forward end position where it protrudes from the machine base. Even if the nails are located, the amount of protrusion can be reduced, and nail replacement can be performed stably. Moreover, at the pawl exchange position B, the engagement and disengagement between the locking part and the engaging part of the exchange device is automatically performed by rotation of the pawl storage magazine, which has the advantage that no special locking and disengaging device is required.

[Brief explanation of drawings]

The drawings show an embodiment of the present application, and FIG. 1 is a cross-sectional view with a part of the claw omitted, FIG. 2 is a cross-sectional view showing the replacement preparation state of FIG. 1, and FIG. An enlarged sectional view, FIG. 4 is a sectional view taken along the - line in FIG. 2, FIGS. 5 and 6 are partial views showing the operating state of FIG. 1,
Fig. 7 is a sectional view showing the operating state of Fig. 3, Fig. 8 is a sectional view showing the operating state of Fig. 1, and Fig. 9 is a sectional view showing the operating state of Fig. 1.
-0-0- line sectional view in the figure, Figure 10 is a side view of the base jaw that constitutes the claw, Figure 10-1
is a top view of Fig. 10, Fig. 11 is a side view of the base jig that constitutes the pawl, Fig. 11-1 is a top view of Fig. 11, and Fig. 12 is a partial side view of the base jyo that constitutes the pawl. Figure-1 is a top view of Figure 12;
FIG. 13 is a partial side view of another embodiment of the top jaw constituting the claw, and FIG. 13-1 is a top view of FIG. 13. 1...Machine tool, 4...Chuck claw automatic change device, 5...Quick change chuck, 13...
Claw, 14...Locking portion, 16...Latching groove, 16a...
... Projection piece, 50 ... Claw storage magazine, 65 ... Replacement device, 67 ... Claw moving device, 74 ... Locking piece,
74a...Engaging portion.

Claims (1)

[Claims] 1. Index the retaining groove of the holder of the nail storage magazine that removably holds a large number of replacement pawls so that it is aligned with the sliding groove of the chuck pawl indexed to the predetermined pawl replacement position, The chuck is equipped with a claw changing device that hooks and moves the claw between the holder and the chuck in this state, and the chuck moves between a non-exchange position away from the chuck and a forward end position protruding from the machine base in the chuck axis direction. A claw used in an automatic claw changing device, which has a locking part near the edge of the claw consisting of a groove that opens toward the back side of the claw or a protrusion that projects toward the back side of the claw. A chuck claw for automatic exchange, which is provided without any barrier on both sides, and the above-mentioned exchange device is engaged and detached from the locking portion.