JPS6026658B2 - Machine tool tool changing device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a cutting tool changing device for a machine tool such as a plano miller, hard lathe, die-sinking machine, etc., in which the main shaft is movable in the horizontal direction and vertical direction. This invention relates to a machine tool tool changing device that is screw-connected.

Conventionally, the attachment of cutting tools in NC machine tools, etc. has been done using taper shanks for relatively large cutting tools, while for small blades it has been done manually using screw connections or wedges. There is.

However, with the rise in labor costs in recent years, blade replacement is becoming automated, but in the case of screw connections, handling is troublesome because the screws are small, and an appropriate automatic screwing and loosening device is required. The current situation is that it has not been developed.

SUMMARY OF THE INVENTION An object of the present invention is to provide a cutting tool changing device for a machine tool that can automatically replace screw-type cutting tools in a machine tool. The present invention rotatably supports a magazine on a base attached to a column of a machine tool, and in this magazine, a plurality of holders storing cutting tools having threaded joints can be freely rotated at equal intervals on the same circumference. A magazine rotation drive mechanism is provided to index the magazine to a predetermined position, so that a predetermined holder can be opposed to the main shaft of the machine tool. A holder advancing/retracting drive mechanism for advancing and retracting the holder toward the main shaft and a holder rotation drive mechanism for rotating the holder are provided to advance the cutter stored in the holder toward the main shaft, and to rotate and connect the cutter with a screw or to connect the cutter already attached to the main shaft. The above object is achieved by releasing the screw connection while rotating the device and storing it in an empty holder.

Hereinafter, one embodiment of the present invention will be described based on the drawings. FIG. 1 shows a blade odor exchange device attached to an NC five-axis control machine such as a die-sinking machine.

In this figure, the NC five-axis controller 10 includes a gate-shaped column 12 erected on a bed 11.
A movable table 14 is supported which is horizontally movable along cross rails 13 provided on the top and front surfaces of the column 12. The movable table 14 is moved in the horizontal direction by a feed screw shaft 16 rotated by a horizontal drive motor 15 provided on a horizontal portion of the column 12. The movable table 14 is provided with a ram 17 that is movable in the vertical direction along guide bars 18 provided on both sides of the ram 17, and a support stand 1 fixed to the upper end of the ram 17.
A vertical movement motor 20 is attached to 9. A feed screw shaft 21 is connected to the output shaft of the motor 20, and the other end of the feed screw shaft 21 is rotatably supported in the middle of the ram 17. A midway portion of the feed screw shaft 21 is screwed into a nut member 22 provided on the movable table 14, so that the ram 17 can be moved up and down by driving the motor 20. Further, a pair of balance cylinders 23 are provided between the support base 19 and the moving base 14 at positions on both sides of the ram 17, and the action of the balance cylinders 23 allows the ram 17 to move up and down smoothly. A pivot shaft 2 is provided at the lower end of the ram 17.
4 is attached to be able to pivot in a horizontal plane about the central axis of the ram 17, and this pivot shaft 24 is pivoted by a pivot drive motor 25 attached to the support base 19 via an interlocking mechanism (not shown). It has become.

Further, a spindle head 26 is provided on the front side of the pivot shaft 24 so as to be able to swing in a vertical plane. Further, the main shaft head 26 is provided with a main shaft 27 having a threaded joint, and the main shaft 27 is rotated at high speed by a motor (not shown). At a position below the main shaft 27, a table 28 for installing a workpiece (not shown) is provided at the center of the bed 11, and this table 28 is driven by a table drive motor (not shown) or the like to a pair of guide rails 29.
It is designed to move forward and backward along the direction perpendicular to the plane of the paper in FIG.

On one of the columns 12 of the NC five-axis controller 10, on the left column in the figure, a clamp device 40 for preventing rotation of the main shaft 27 when changing the cutting tool and a cutting tool changing device 50 according to the present invention are attached.

As shown in enlarged view in FIGS. 2 and 3, the clamping device 40' includes a mounting base 41 to the column 12, a fixing base 42 attached to the mounting base 41, and a fixing base 42 attached to the mounting base 41.
a movable member 43 that is slidably supported by the fixed base 42 and has a movable side clamping claw 43A opposed to a fixed side clamping claw 42A formed by thinning a part of the fixed base 42; A piston rod 44A passes through a movable member 43 and includes a head clamp cylinder 44 fixed to the movable part village 43. By operating this cylinder 44, the main shaft 27 is moved between the clamping claws 42A and 43A. It can be held in place to prevent rotation.

The main shaft 27 has, as shown enlarged in FIG.
A cutting tool 30 having a screw hole as a screw connection part is attached to the main shaft 27.
They are screwed together via an adapter 27A that constitutes a part of the.

This adapter 27A is screwed and fixed to the main body side of the main shaft 27 by a male threaded portion 27B at one end, and a male threaded portion 27C at the end is screwed into a threaded hole of the cutter 30, and the male threaded portion 27C is used for screw connection. The department is made up of: The cutter changing device 50 includes a base 51, and a support tube 52 erected on the base 51 has a bare IJ.
A magazine 54 for storing cutting tools is rotatably supported via a ring 53.

This magazine 54 has upper and lower flange portions 54A and 54B, and a ring gear 55 is integrally fixed to the lower end. A pinion 56 is meshed with the ring gear 55, and the pinion 56 is fixed to the output shaft of a magazine rotation hydraulic motor 57 fixed to the base 51. As a result, by driving the motor 57, the magazine 54 can be rotated via the pinion 56 and the ring gear 55, and these motors 57,
The pinion 56 and ring gear 55 constitute a magazine rotation drive mechanism. Near the outer periphery of the flange 54A above the magazine 54, a plurality of, for example, 2N hard bushes 58 are installed at evenly spaced positions (see FIG. 6), and these bushes 58 have approximately cylindrical cutter supporting blades. Holder 5
9 are supported so as to be movable in the rotation axis direction (vertical direction) of the rotatable brackets, and furthermore, these holders 59 are prevented from falling downward by a retaining ring 60 fixed to the upper part of the holder 59, and are always Each holder 59 hangs downward due to gravity and is locked by a retaining ring 6.

Moreover, the positions where each of these holders 59 are provided are as follows.
When the main shaft 27 of the NC five-axis controller 10 is at the cutting tool exchange position, that is, the left chain line position in FIG. 1 or the solid line position in FIG. The lines are placed so that they exactly match. Therefore, as the magazine 54 rotates, each holder 59 rotates while passing just below the main shaft 27 located at the cutting tool exchange position. On the upper end surface of each holder 59, as shown enlarged in FIGS. 4 and 5,
A pair of planar sector-shaped anti-rotation protrusions 59A are provided at 180 degree positions, and these protrusions 59A
They are respectively engageable with rotation prevention protrusions 30A provided on the periphery of the upper end and also have a planar sector shape, so that rotation can be prevented.

Furthermore, the partition wall 5 formed at the center of the inner lining of each holder 59
9B, the upper part of a locking shaft 61 is attached to the inner circumference of the holder 59 so that the upper part of the locking shaft 61 can be moved freely and prevented from coming off downward (see FIG. 2). The partition wall 5 between the engagement bush 63 and the holder 59, in which the engagement push 63 which is prevented from rotating is fixed by press-fitting or the like.
A compression coil spring 64 is interposed between the engagement bush 63 and the engagement bush 63. Further, on the lower surface of this engagement push 63, a rotation prevention protrusion 59A formed on the upper end surface of the holder 59 is provided.
Two anti-rotation protrusions 63A having a fan-like planar shape similar to the above are integrally provided at 180 degree positions. A spline shaft 65 is disposed opposite to the surface of the holder 59 opposite to the main shaft 27, which is opposite to the surface facing the main shaft 27 (see FIG. 2);
The spline shaft 65 is connected to the center of the large gear 66 so that it can slide freely in the axial direction and cannot rotate with respect to the other.

This large gear 66 is rotatably supported by the base 51 via a bearing 67, and a hydraulic motor 6 as a drive source for rotating the holder is mounted on the teeth provided on the outer periphery of the upper end.
A small gear 69 fixed to the output shaft of 8 is meshed.
Further, the holder 59 is provided on the upper end surface of the spline shaft 65.
Two anti-rotation protrusions 65A having a fan-shaped plane similar to the anti-rotation protrusion 59A formed on the upper end surface are integrally provided at 180 degree positions, and these protrusions 65A are engaged with the protrusions 63A of the engagement bush 63. When engaged, the spline shaft 65, the engagement push 63, and the holder 59, which is prevented from rotating by the engagement bush 63 via the key 62, can rotate together. Therefore,
As the motor 68 rotates, the holder 59 is rotated via a small gear 69, a large gear 66, a spline shaft 65, an engagement bush 63, etc.
8, a small gear 69, a large gear 66, and a spline shaft 65 constitute a holder rotation drive mechanism. A male thread 65B is integrally formed at the lower part of the spline shaft 65, and this female thread 658 is screwed into a nut member 70.
These male screws 65B and the nut member 70 constitute a screw feeding means.

At this time, the male thread 65B of the spline shaft 65 and the cutter 3
The thread pitch between the male thread 27C of the adapter 27A and the male thread 27C to which the adapter 27A is screwed is made equal, and the amount of axial movement of the spline shaft 65 due to the rotation of the spline shaft 65 and the amount of movement of the cutter 30 in the axial direction due to the rotation of the cutter 30 are equal. are made to be exactly equal. Further, the nut member 70 is fixed to a movable plate 71, and this movable plate 71 is connected to a substantially gate-shaped mounting base 7.
2 to the tip of the piston rod 73A of the cylinder 73 for pushing and pulling the holder, and as the cylinder 73 is driven, the spline ratchet 65 is moved in the axial direction via the mounting base 72, the movable plate 71, and the nut section 70. It is now possible to advance and retreat. This cylinder 73 is fixed to a cylinder support frame 74 provided perpendicularly to the movable plate 71 and so as to straddle the movable plate 71 and the motor 68. This support frame 74 is fixed to the bottom surface of the base 51. ing. Here, the movement mechanism extending from the cylinder 73 to the spline shaft 65 constitutes a holder advance/retreat drive mechanism. First and second limit switches 75 and 76 are mounted on the bottom surface of the movable plate 71 at different vertical mounting positions, and these first and second limit switches 7
5 and 76 are actuated by an actuating body 77 fixed to a lower end of the spline shaft 65 than the male threaded portion 658.

This actuating body 77 is formed into a disk shape, and its periphery has a shape in which the central part of the periphery protrudes.When this actuating body 77 moves downward, in other words, the first limit switch 75 is activated by the holder 59. The spline shaft 65 moves in the direction of loosening the cutting tool 30 via the spline shaft 65, and when the loosening limit is reached, the second limit switch 76 is actuated to detect the loosening limit, while the second limit switch 76 is activated when the actuating body 77 moves upward. That is, the spline shaft 65 moves in the direction of tightening the cutting tool 30 via the holder 59, and when the tightening limit is reached, the spline shaft 65 is activated to detect the tightening limit. These first and second limit switches 75 and 76 are each connected to a power circuit (not shown) for switching the hydraulic circuit of the hydraulic motor 68, and when each limit switch 75 and 76 is activated, the motor 68 is driven. Been trying to stop. Furthermore, these limit switches 75, 7
6 constitutes a detection means for detecting forward and backward movement of the holder 59. A circular flange portion 59C is provided at the lower end of the holder 59, and a plate-shaped locking member 78 is formed on one side of the flange portion 59C, as shown in FIGS. 2 and 6. The recessed portion 78A can be locked.

This locking member 78 is fixed to the upper ends of two guide shafts 79, and these guide shafts 79 are slidably supported by the base 51. The lower end of the guide shaft 79 projects through the movable plate 71, and a compression coil spring 80 is inserted between the lower end and the movable plate 71.
The locking portion village 78 is always urged downward by the urging force of the locking portion village 78, so that the holder 59 locked to the locking portion village 78 is reliably pulled downward by the locking member 78. Further, due to the action of these two guide shafts 79, the locking member 78 is moved up and down in a straight line without rotating, and even when the moving plate 71 is moved up and down by the cylinder 73, the moving plate 71 is also rotated. It is recommended not to do so. In addition, in FIG. 2, the guide shaft 79 is not actually located at the position shown in the figure, but as shown in FIGS. However, for convenience of illustration, the position has been changed.

Therefore, the locking member 78 is also not elongated vertically in the left-right direction as shown in the second figure, but is rather elongated horizontally and long toward both guide shafts 79 as shown in FIG. 6. 6 is a view of FIG. 2 viewed from the plane with different cross-sectional positions, and the left range A in FIG. Range B from the left side to the bottom right is the second
A cross-sectional view of WB- in the figure taken in the direction of arrow B, and a range C above the stone is a cross-sectional view taken in the direction of arrow c of Wc- in FIG. A connecting member 83 in the shape of a shallow dish is fixed to the raised part of the magazine 54 (see FIG. 2), and the upper end of a connecting shaft 85 is fixed to the center of this connecting member 83 via a key 84. ing.

The connecting shaft 85 extends inside the support tube 52 and is rotatably supported by the support tube 52 via a bearing 86 at its lower end, and the output of the holder selection limit switch 88 is connected to the lower end via a coupling 87. connected to the shaft. This limit switch 88 is a type of rotary switch called a pulse coder or the like, and is configured to detect which holder 59 is opposed to the main shaft 27 and the spline shaft 65. As shown in FIGS. 6 to 8, one side of the base 51 is provided with a magazine positioning stop mechanism 90 for stopping each predetermined holder 59 with the center of the holder exactly aligned with the main holder 27. There is.

This stopping mechanism 90 is connected to the lower flange 5 of the magazine 54.
The base 51 has a locking protrusion 91 buried at a fixed pitch in accordance with the mounting pitch of the plurality of holders 59 in the base 4B, and a notch 92A (see FIG. 8) that can be engaged with the locking protrusion 91. A substantially disk-shaped stopper 92 is rotatable through a shaft 93 in a notched groove 51A provided in the groove 51A, and has one side cut out in a V-shape. The end face can be supported and the base 5
A stop position fine adjustment bolt 95 screwed in from one green end of the stopper 92 with its tip protruding into the notched groove 51A and lockable with a lock nut 94, so as to close the stopper 92 and the notched groove 51A. Both ends are fixed between the cover body 96 attached to the base 51 and the stopper 92 is attached clockwise as shown by arrow P in FIG. A torsion coil spring 97 that is biased and an actuating piece 98A that is attached to the bottom surface of the base 51 and can be oscillated are connected to the operating groove 51A.
The limit switch 98 is inserted into the inner circumferential surface of the stopper 92 and can be applied to the circumferential surface of the stopper 92. This limit switch 98 is connected to a power supply circuit (not shown) for switching the hydraulic circuit of the magazine rotation hydraulic motor 57 It is connected to the.
At this time, the limit switch 98 is activated when the magazine 54 is rotated significantly in the left direction as indicated by the arrow Q in FIG. When the holder selection limit switch 88 detects that the predetermined holder 59 coincides with the position of the main shaft 27, it becomes operable. When it comes into contact with the circumferential surface, it acts to rotate the hydraulic motor 57 in the opposite direction, thereby causing the locking protrusion 91 to come into contact with the notch 92A of the stopper 92, and the locking protrusion Part 9
A part of the stopper 92 is held between the stopper 1 and the fine adjustment bolt 95, so that the magazine 54 is accurately stopped at the localization layer. The operation of this embodiment will be explained below. In FIG. 1, the workpiece (not shown) placed on the table 28 is machined by moving the cutting tool 30 attached to the spindle 27 in a horizontal plane using the movable table 14 according to a pre-digitized program. Left/right direction, ram 1
7 in the vertical direction, the rotation axis 24 in the horizontal plane rotation direction, the spindle head 26 in the vertical plane neck direction, and the table 28 in the horizontal plane front and back directions.

When machining with one cutting tool 30 is completed in this way and processing is performed by replacing it with another cutting tool 30, the movable table 14,
By moving the ram 17, etc., the spindle head 26 is moved to the position indicated by the chain line on the left in FIG. The explanation will be given from the beginning of machining, when the cutting tool 30 is not yet attached, or from the state where the cutting tool 30 has already been removed.

Prior to moving the spindle head 26 to the cutting tool exchange position,
The magazine 54 of the blade odor exchange device 50 is rotated by a hydraulic motor 57, and the first (or next)
A cutting tool 30 necessary for machining is selected in advance, and the necessary cutting tool 30 is positioned just below the cutting tool replacement position of the spindle head 26. Next, when the spindle head 26 is moved to a position directly above the preselected cutter 30 and stopped, the adapter 27A of the spindle 27 is moved between the fixed side clamping claw 42A and the movable side clamping claw 43A of the clamping device 40.
It is held between the cylinder 44 and prevented from rotating (see FIG. 3).

At this time, when replacing the cutting tool 30 with the cutting tool 30 for the next processing, the adapter 27A has already been clamped by the clamping device 4 when the cutting tool 30 for the previous processing is removed. In this state, the shilling 73 for vertical movement of the spline shaft
(See FIG. 2) is operated to advance the piston rod 73A. Along with this advancement of the piston rod 73A,
The spline shaft 65 is also raised, and the upper end of the spline shaft 65 comes into contact with the lower end of the holder 59, and when the holder 59 is also raised and the stroke end of the cylinder 73 is reached,
It is assumed that the blade 30 supported by the holder 59 and the lower male screw 27C of the adapter 27A are close to each other. At this time, the anti-rotation protrusion 65A on the upper end surface of the spline shaft 65 and the anti-rotation protrusion 63A on the lower end surface of the engagement bush 63 of the holder 59 happen to be in a state in which their end surfaces are just touching each other, while the holder Anti-rotation protrusion 5 on the upper end surface of 59
9A and the anti-rotation protrusion 30A on the upper outer periphery of the cutter 30 are exactly connected to each other when the cutter 30 is attached to the holder 59.
Assuming that the protrusions 59A and 30A are placed between each pair of protrusions 59A and 30A so that they do not come into contact with each other,
At this time, the dimensions are set so that the tip of the lower female thread 27C of the adapter 27A is in almost abutment with the entrance end of the screw hole of the blade 30. Next, when the hydraulic motor 68 for rotating the holder is rotated even a little, the small gear 69 is rotated.
, the spline shaft 65 is rotated via the large gear 66, and the lower protrusions 63A and 65A, which are threaded against each other with their end faces, enter between each other, and the holder 59 is moved by its own weight and the locking member 7.
8 falls slightly downward, and the center screw hole of the cutter 30 and the male thread 27C of the adapter 27A are slightly separated.

At this time, depending on the positional relationship between the lower protrusions 63A and 65A, such a state may occur directly even without rotation of the motor 68. Further, as the spline shaft 65 rotates, the male threaded portion 6 integrally formed on the spline shaft 65 is rotated.
5B is also rotated, and this rotation direction is the male threaded portion 65B.
Since the spline shaft 65 is moved upward in relation to the nut member 70, as the spline shaft 65 rotates, the spline shaft 65 also sequentially rises using the spline portion as a guide. When the spline shaft 65 is further rotated, the lower protrusions 63A and 65A inserted between them support each other and become in a state similar to that shown in FIG. 5, whereby the holder 59 is also rotated at the same time as the spline shaft 65. , and is sequentially raised by the action of the male threaded portion 65B of the spline shaft 65, and the male thread 27C of the adapter 27A is sequentially screwed into the threaded hole of the cutting tool 30.

At this time, the thread pitch of the male thread 27C and the spline shaft 65
Since the thread pitch of the male threaded portion 65B is the same as that of the spline shaft 65, the amount of rise of the spline shaft 65 and the amount of threading between the threaded hole of the cutter 30 and the male thread 27C are the same, so the threading work can be performed smoothly. It will be done. Next, cutter 30
When the male screw 27C of the adapter 27A is screwed in to the proper amount, the actuating body 77 fixed to the lower end of the spline shaft 65 is assisted by the actuating end of the second IJ limit switch 76, and this limit switch 76 When actuated, the drive of the hydraulic motor 68 is stopped and the push/pull cylinder 73 is actuated in the direction of contraction of the piston rod 73A.

Along with this reduction of the piston rod 73A, the moving plate 71
The spline shaft 65 is lowered through the holder 5.
9 also moves downward due to its own weight as the spline shaft 65 supporting the holder 59 descends, leaving only the blade shell 30 behind on the adapter 27A of the main shaft 27. At this time, as the movable plate 71 is lowered, the guide shaft 79 is also lowered via the compression coil spring 80, and the flange portion 59C of the holder 59 is pressed downward via the locking member 78.
Since the holder 59 is pushed down not only by its own weight but also by this biasing force, it is reliably lowered. The main shaft 27 to which the cutter 30 is attached in this way is attached to the table 28.
It is moved onto the workpiece that has been reloaded on top, and a predetermined process is performed.

On the other hand, when machining is completed and the next cutting tool 30' is to be replaced, the spindle 27 is moved to the cutting tool replacement position in the same manner as described above, and the holder 59 is moved to the empty space where the cutting tool 30 currently being processed was placed. The holder 59 is located at the cutting tool exchange position.

When the cylinder 73 is raised in this state, the holder 69 is pushed up via the spline shaft 65, and the cutter 30 is inserted into the upper end of this empty holder 59. At this time, since the male threaded portion 65B of the spline shaft 65 is in a state of being moved upwardly against the nut member 70', when the cylinder 73 is operated to the stroke end, the cutter 30 is removed from the upper end surface of the spline shaft 65. The dimension to the lower surface of the rotation prevention protrusion 30A is exactly equal to the free length of the holder 59, so that the protrusion 30A of the upper cutter 30 and the holder 5
9 protrusion 59A and the protrusion 63 of the lower engagement bush 63
If both the protrusions 65A of the spline shaft 65 come into contact with each other at the end surfaces, each protrusion 30A on both the upper and lower
59A and the overlapping portions of protrusions 63A and 65A, some of them must be reduced to absorb the dimensional difference.
This dimension is absorbed by the engagement bush 63 being retracted into the holder 59 against the compression coil spring 64. Then, when the motor 68 is driven in the opposite direction to that described above and the spline shaft 65 is rotated, the upper protrusions 30A and 59A and the lower protrusions 63A and 65A are moved between each other in the same manner as described above. entered, then engaged with each other,
The cutter 30 is rotated in the loosening direction. Due to this rotation in the loosening direction, the cutting tool 30 gradually protrudes downward, but
This protrusion is absorbed by the male threaded portion 65B of the spline shaft 65 sequentially moving downward relative to the nut member 701. At this time, the thread pitch of this male threaded portion 65B and the cutter 3
Since the protrusion pitch of 0, that is, the thread pitch of the male thread 27C, is made equal, this loosening operation can be performed very smoothly. In this way, when the loosening of the cutter 30 is completed, the actuating body 77 at the lower end of the spline shaft 65 actuates the first limit switch 75, and thereby the motor 68
rotation is stopped, and the piston rod 73A of the cylinder 73 is contracted to complete the removal of the cutter 30.

Then, the hydraulic motor 57 for driving the magazine is operated again, and a predetermined holder 59 is selected by the action of the holder selection limit switch 88 and the magazine positioning layer stop mechanism 90. Thereafter, the attachment of the cutting tool 30 is performed in the same manner as described above. It will be done.

As described above, this embodiment has the following effects. That is, it is possible to automate the replacement of the screw-coupled cutting tool 30 in a relatively small-sized NC machine tool, and it is much more efficient than the conventional manual work.

In addition, the male thread 2 of the adapter 27A that is combined with the cutter 30 is
7C is a small-diameter screw, so when manually tightening the screw, the life of the screw would be shortened due to over-tightening, but in this example, it can be tightened automatically with almost constant pressure, so the screw life is shortened. The lifespan of can be extended. Furthermore, in this embodiment, since the hydraulic motor 68 is used as the rotational drive source for tightening and loosening the screw, the torque during loosening can be easily increased by changing the working fluid pressure, making the loosening work extremely easy. It can be done smoothly. Furthermore, in this embodiment, since the thread pitch of the male thread 27C screwed to the cutter 30 and the thread pitch of the male thread portion 65B of the spline shaft 65 are made equal, tightening and loosening of the screw, especially loosening work, is made easier. It can be done smoothly.

Furthermore, since the completion of tightening or removal of the cutter 30 can be detected by detecting the amount of movement of the spline shaft 65 using the first and second limit switches 75 and 76, it is possible to detect the completion of tightening or removal of the cutter 30 by detecting the amount of movement of the spline shaft 65 using the first and second limit switches 75 and 76. Unlike the conventional method, there is no possibility of malfunction when the torque temporarily increases during the advance/retreat process due to galling of the screw, etc., and the work can be performed reliably. In addition, the compression coil spring 8
Since the flange portion 59C of the holder 59 is urged downward by the locking member 78 which is always urged downward from the river, the holder 59 can be dropped more reliably than when the holder 59 is dropped simply by its own weight. can be done.

Further, the magazine 54 has a magazine positioning layer stop mechanism 90'.
Since it can be reliably stopped on the stereotactic layer, the center of the main shaft 27 and the center of the holder 59 can be aligned accurately. Further, since the engagement bush 63 is slidably provided on the holder 59, each of the protrusions 30A, 59A, 63A,
Even when 65A overlap each other, it can be sufficiently coped with. In the above embodiments, the present invention has been described as an example of a cutting tool changing device for an NC five-axis control machine, but the present invention is not limited to this, and can be applied to, for example, a plano mirror,
The present invention can be applied as a tool changing device for machine tools such as hard lathes and die-sinking machines in which the main shaft is movable at least horizontally and vertically relative to a column.

In this case, when the cutting tool is small, the mounting structure is simple, so screw connection of the cutting tool is advantageous, so the present invention is more effective. Further, although the holder is vertical in the above embodiment, it may be horizontal, and the number of holders is not limited to 20, but may be any number. Furthermore, the number of main spindles and spline shafts of the machine tool is not limited to one set, but may be two or more sets. Further, the rotation preventing means is not limited to the projections, but may have other structures such as a projection and a recess. Furthermore, the buffer means consisting of a locking shaft and a spring provided on each holder may be provided on the spline shaft side,
In this case, the spline shaft has an expandable double shaft foundation, a so-called floating structure. In addition, if the spline shaft has a floating structure in this way, it becomes possible to smoothly connect and loosen the screws without matching the thread pitch of the threaded joint portion of the cutting tool and the male threaded portion of the spline shaft.
As described above, according to the present invention, there is an effect that it is possible to provide a cutting tool changing device for a machine tool that can easily perform a blade odor changing operation in a machine tool.

[Brief explanation of drawings]

Fig. 1 is a front view showing the overall configuration of an example in which the cutting tool changing device according to the present invention is applied to an NC five-axis control machine, Fig. 2 is an enlarged vertical cross-sectional view of the main parts, and Fig. 3 is similar to Fig. FIG. 4 is an enlarged sectional view of the operating state in FIG. 2, FIG. 5 is a sectional view along the line V-V in FIG. 4, and FIG. The figure is a cross-sectional view of the loss of vision along the W^-W^ line, Machi 81 WB line, and Wc-Wc line in Figure 2, and Figure 7 is a bottom view of Figure 2.
FIG. 8 is a schematic sectional view taken along the straight line of the shelf in FIG. 6. 10...NC five-axis controller, 12,...column, 14
...Moving table, 17... Ram, 27... Main shaft, 27
A... Adapter, 27C... Male thread, 30... Cutting tool, 30A... Anti-rotation protrusion, 40... Clamping device, 50... Cutting tool changing device, 51... Base, 5
4...Magazine, 55...Ring gear, 56...
Pinion, 57... Hydraulic motor, 59... Holder,
59A... Anti-rotation protrusion, 63... Engagement bush, 63A... Anti-rotation protrusion, 65... Spline rat, 65A... Anti-rotation protrusion, 65B... Male threaded portion, 66 ...Large gear, 68...Hydraulic motor, 69...
Small gear, 70... Nut member, 71... Moving plate, 7
2... Mounting base, 73... Cylinder, 75, 76... First and second limit switches, 88... Limit switch for holder selection, 90... Magazine localization layer stop mechanism. Figure 1 Figure 2 Figure 3 Figure 5 Figure 4 Figure 6 Figure 7 Figure 8

Claims (1)

[Scope of Claims] 1. A cutter changing device that is attached to a machine tool, in which a main shaft is movable at least horizontally and vertically relative to a column, and a cutting tool is detachably attached to the main shaft by screw connection. , a base is attached to one side of the column, a magazine is rotatably attached to this base, and a plurality of cutter supporting holders are arranged at equal intervals on the same circumference of this magazine, each of which is rotatable and movable in the direction of this rotation axis. A cutting tool having a threaded connection part is housed in these holders in a state that prevents it from rotating and is removable in the axial direction, and the main shaft of the machine tool has a screw threadedly connected to the threaded connection part of the cutting tool. A coupling part is provided, a magazine rotation drive mechanism is provided for indexing a predetermined holder among the holders of the magazine facing the main shaft, and a holder advancement/retraction drive mechanism is provided for moving the holder facing the main shaft forward and backward toward the main shaft. At the same time, the holder, which is advanced toward the main shaft by this holder advance/retreat drive mechanism and is opposed to the main shaft in a state where it approaches the main shaft, is rotated in a predetermined direction to connect or release the threaded joint between the main shaft and the cutting tool. A cutting tool changing device for a machine tool, characterized by being provided with a holder rotation drive mechanism. 2. In claim 1, the holder rotation drive mechanism is configured to be able to rotate the holder in both forward and reverse directions, and the holder advance/retreat drive mechanism includes a detection means for detecting the limits of forward and backward movement of the holder. A cutting tool changing device for a machine tool, which is characterized by: 3. In claim 1 or 2, the holder advancing/retracting drive mechanism includes a screw feeding means, and a screw pitch of the screw feeding means and a screw pitch of the threaded connection portion of the cutting tool and the main shaft. A cutting tool changing device for a machine tool, characterized in that: