JPH04250912A - Cutting tool for inversed spot facing and replacing device thereof - Google Patents

Abstract

PURPOSE:To automatically detach/replace a milling cutter for inversed spot facing. CONSTITUTION:A cutting member 15 is subjected to spline engaging with a rotating driving shaft 13. A retaining member 16 is provided at an end D of the cutting member 15 while it is urged to stick thereto. A ball 23 resin and set by these approaches/separations is provided. A slide body 27 is fitted into a cylindrical body 25 having an arm 26 which holds the cutting member 15. An arm 28 engaged with the retaining member 16 is provided on the slide body 27. The cutting member 15 is made to approach and separated from the pressing member 16, with the cylindrical body 25 only being moved by the air pressure fed from an air passage 38. The ball 23 is then risen and set, and the cutting member 15 is separated from the rotating drive shaft 13. Moreover a cutting member 31 and retaining member 32 are provided while other arms 29, 30 are provided. The members 31, 32 for replacement are fitted to the rotating driving shaft 13 with the slide body 27 and cylindrical body 15 being revolved by an air motor 43.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a back counterboring cutting tool equipped with a milling cutter and a changing device therefor.

0002

[Prior art] Machine tool (cutting machine) that performs milling
When performing back-spot boring of a shaft hole, if the diameter of the hole is relatively large and the back-spot boring diameter is slightly larger than the diameter of the shaft hole, use a rod-shaped side milling cutter (end mill) perpendicular to the main shaft of the machine. The back seat portion is formed by attaching the tool in the direction of the tool, rotating the tool around its axis, and inserting the main shaft of the machine eccentrically into the shaft hole and moving it along the hole wall.

In addition, when the diameter of the shaft hole is relatively small and the diameter of the back counterbore is large compared to the shaft hole, as in the hub part of a compressor, the main shaft 1 is inserted into the shaft hole as shown in FIG. 2
At the same time, a milling cutter (face milling cutter) 4 with a cutting edge 3 implanted on the front side is fixed to the tip of the main spindle 1 with a grooved nut 5 or the like.
The main shaft 2 is rotated while being pulled forward to form the back seat portion 6 at a predetermined location on the workpiece W.

0004

[Problems to be Solved by the Invention] However, when performing back countersinking using such a milling cutter 4, the milling cutter 4 must be attached manually after the main shaft 1 is passed through the shaft hole 2. Must be.

That is, when starting a new counter-boring process or replacing the milling cutter 4 depending on the finishing stage, the operator must be close to the machine, and the cutting machine is automatically controlled. Even if NC machine tools (NC machine tools) were adopted, there were problems in that it was not possible to save on manpower, and that it took time to attach, detach, and replace, reducing the efficiency of cutting work.

In view of the above-mentioned circumstances, the present invention was devised to provide a back counterboring cutting tool and its exchange device that can quickly and automatically attach/detach/exchange a milling cutter to a machine main shaft. It is.

[0007]

[Means for Solving the Problems] The present invention includes a rotary drive shaft that is inserted into a shaft hole formed in a workpiece so as to be able to move forward and backward, and a rotary drive shaft that is provided at the tip of the rotary drive shaft and is seated on the back side of the workpiece. In a back counterboring cutting tool having a milling cutter for cutting a part, a cutting member is spline-fitted to a rotary drive shaft and has a milling cutter on the base end side, and a distal end side of the cutting member. A rotary drive shaft having a presser member provided between the presser member and the cutting member that is biased toward each other, and a ball that is provided between the presser member and the cutting member and that moves in and out of the rotary drive shaft as the presser member and the cutting member approach and separate from each other. and a mechanism for attaching and detaching the cutting member.

The present invention also provides a device for handling the above-mentioned back counterboring cutting tool, which includes a cylindrical body extending parallel to the rotational drive shaft, and a cylindrical body supported by the cylindrical body for holding a cutting member. A first arm that extends, a sliding body that is fitted into the cylindrical body and is formed to be able to move relative to each other in the axial direction, and a second arm that is supported by this sliding body and that extends to engage with the presser member. It is equipped with an arm.

[0009] The above device includes a cylindrical body extending parallel to the rotational drive shaft, and a plurality of first arms supported by the cylindrical body and extending radially to hold the cutting member and the replacement cutting member. a sliding body that is fitted into the cylindrical body and is formed to be relatively movable only in the axial direction; and a sliding body that is supported by the sliding body and extends radially to engage with the pressing member and the pressing member provided on the replacement cutting member. a plurality of second arms, which move the cylindrical body as appropriate to cause the first arm to separate the cutting member from the holding member; It is preferable to include a turning drive means for appropriately positioning the rotation drive shaft at the tip of the rotation drive shaft.

0010

[Operation] With the above configuration, the cutting member receives the rotation of the rotary drive shaft and forms a back seat around the shaft hole, and
When separated from the presser member, the ball of the attachment/detachment mechanism retracts and can be detached from the rotational drive shaft.

[0011] Furthermore, with the configuration including the cylindrical body, the first arm, the sliding body, and the second arm, the pressing member is engaged with the second arm, and at the same time, the cutting member is moved in the separating direction by the first arm. The attachment/detachment mechanism is activated to detach the rotary drive shaft.

Further, with the configuration including the attachment/detachment drive means and the rotation drive means, the cutting member fixed to the rotary drive shaft is separated from the presser member by the attachment/detachment drive means moving the cylindrical body and the first arm. The ball of the attachment/detachment mechanism retracts and is released. Then, the turning drive means turns the detached cutting member and engages another cutting member with the rotary drive shaft. Thereafter, the attachment/detachment driving means causes the cutting member spline-fitted to the rotational drive shaft to approach the holding member, protrudes the ball, and fixes the cutting member to the rotational drive shaft.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Examples of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 shows an embodiment of a back counterboring cutting tool and its exchange device according to the present invention.

[0015] This back counterboring cutting tool 11 is used to cut the workpiece W.
a rotational drive shaft 13 inserted into a shaft hole 12 formed in
A cutting member 15 spline-fitted to the distal end side D of the rotary drive shaft 13 and having a milling cutter 14, a presser member 16 provided on the distal side D of the cutting member 15, and a space between the presser member 16 and the cutting member 15. It is mainly constituted by an attachment/detachment mechanism 17 provided in the.

The rotational drive shaft 13 is attached to the main shaft (milling shaft) 19 of the cutting machine body 18 via a floating holder 20, and the rotational driving force from the main shaft 19 is transmitted, and the rotational drive shaft 13 can move forward and backward into the shaft hole 12. It looks like this. The milling cutter 14 is provided on the proximal end side (machine main body side) E of the cutting member 15, and when it is rotated, a driving force that is pulled toward the axial proximal end side E is transmitted, thereby cutting the shaft hole 12. The seat portion 21 is formed by cutting the periphery of the seat portion 21 . The holding member 16 is removably fitted to the tip of the rotary drive shaft 13, and is connected to the cutting member 15 via a biasing means 22 that biases them in a direction toward each other. Further, the attachment/detachment mechanism 17 is connected with a ball 23 that protrudes from or sinks into the rotary drive shaft 13 as the holding member 16 and the cutting member 15 approach or separate. That is, the cutting member 15 and the pressing member 16 are fixed to the rotary drive shaft 13 by the protruding ball 23.

Further, the changing device 24 of the present invention is capable of changing the cutting tool 1
1, a cylinder 25 extending parallel to the rotary drive shaft 13, and a first arm 26 supported by the cylinder 25.
, a sliding body 27 fitted into the cylindrical body 25 , and a second arm 28 supported by the sliding body 27 .

The sliding body 27 is formed to be able to move relative to the cylindrical body 25 in the axial direction, and both ends of the sliding body 27 in the axial direction protrude from the end of the cylindrical body 25. Also arm 26,2
8 is attached to the tip side D side wall of the cylinder body 25 and to the tip of the sliding body 27, respectively, the first arm 26 is attached to the cutting member 15 of the cutting tool 11, and the second arm 28 is attached to the presser foot. In order to engage with the member 16, each is bent and extended as appropriate. In this embodiment, a plurality of arms 26 and 28 are formed extending radially, one of which is attached to the cutting member 15 and the holding member 16 of the cutting tool 11, and the remaining arm 29 is attached to the cutting member 15 and the holding member 16 of the cutting tool 11. , 30 can be held and engaged with the replacement cutting member 31 and presser member 32, respectively.

The exchange device 24 is further provided with an attachment/detachment drive means 33 for appropriately moving the cylinder 25, and a rotation drive means 34 for rotating the cylinder 25 and the sliding body 27.

The proximal E end of the sliding body 27 extends toward the machine body 18, and is provided with a base cylinder 36 that rotatably accommodates this extended portion 35. This base cylinder 36 is supported by the machine body 18 via a bracket 37, and is adapted to substantially hold the entire exchanger 24 in a predetermined position. An air passage 38 is formed within the sliding body 27, one end 39 of which is opened to the outside of the device, and the other end 40 of which is opened to a pressure air chamber 41 formed between the sliding body 27 and the cylindrical body 25. ing. That is, when pressurized air is supplied to the air passage 38, the pressure chamber 41 is expanded and the cylindrical body 25 is pushed toward the proximal end side E. This pushing movement causes the first arm 26 to separate the cutting member 15 from the holding member 16 and release the fixation by the attachment/detachment mechanism 17 . That is, these air passages 38 and pressure chambers 41
Thus, the attachment/detachment driving means 33 is configured.

An air motor 43 having a rotation output shaft 42 is attached to the side of the base cylinder 36, and a rotation transmission mechanism 44 is attached to the end of the extension 35 of the sliding body 27 protruding from the base cylinder 36. Some sprockets 45, 46
and are connected via a chain 47. air motor 4
3, when the sliding body 27 is rotated around the axis, the cylindrical body 25 restrained in the rotational direction by the sliding body 27 is rotated.
rotate simultaneously, and the respective arms 26, 28, 29,
30 is rotated so that its extending end can be moved to the tip position of the rotary drive shaft 13 as appropriate. That is, the air motor 43 and the rotation transmission mechanism 44 constitute the swing driving means 34.

Next, details of the back counterboring cutting tool 11 will be explained with reference to FIGS. 2 and 3.

The rotary drive shaft 13, except for its tip, is covered and protected by a guide bush 48. A spline 49 is formed on the outer periphery of the proximal end E of the distal end portion, and is adapted to mesh with the cutting member 15. The spline 49 has a rounded tip, similar to an involute spline in a transmission mechanism of an automobile.

The cutting member 15 is formed by combining two blocks, and three types of cutting edges 50, 51, 52 are installed in steps from the proximal end E to the proximal side and side surfaces, and a spline 54 is formed. A first block 53, which is the milling cutter 14, and a second block 56, which engages with the ball 23, which is the detachable mechanism 17, are arranged in sequence. The first block 53 and the second block 56 are connected by a bolt 57 extending in the axial direction. These bolts 57 are arranged at equal intervals in the circumferential direction, and a total of four bolts are provided together with other bolts (not shown). Moreover, the second block 56 is
It is formed so as to be located on the distal end side D of the first block 53, and on its outer periphery, the first arm 2 protruded from the front is provided.
A retaining groove 58 is formed to fit into the extending end of 6.

The holding member 16 has the same outer diameter as the second block 56, and has an engagement groove 59 formed in its outer circumference to be engaged with the extending end of the second arm 28. . Further, the inner diameter portion extends toward the base end side E in the shape of a boss, and is inserted between the second block 56 and the rotary drive shaft 13. Note that an adjustment liner 60 for adjusting the length in the axial direction is interposed between the second block 56 and the holding member 16.

The biasing means 22 includes a bolt-shaped rod 61 whose tip is embedded in the pressing member 16, and a head 62 of the bolt-shaped rod 61.
A housing hole 63 is formed in the second block 56 so as to be able to move forward and backward, and a compression spring 64 is provided between the head 62 and the stepped portion of the housing hole 63. Therefore, under normal conditions, the elastic force of the compression spring 64 causes the presser member 16 and the cutting member 15 to move toward the adjustment liner 60.
It is attached in the axial direction through.

The attachment/detachment mechanism 17 includes a ball 23 made of a steel ball with a diameter of approximately 15 mm, and a ball accommodating portion 65 for accommodating and holding the ball 23. The ball accommodating portion 65 is formed in a circumferential groove 66 formed at the tip of the rotation drive shaft 13, a round hole 68 formed in the extension insertion portion 67 of the holding member, and a corner on the inner diameter side of the tip of the second block 56. It is divided by two stages of circumferential grooves 69 and 70 formed therein. The wall surfaces of these circumferential grooves 66, 69, and 70 and the round hole 68 are formed by arcuate surfaces having a radius equal to or slightly larger than the spherical surface of the ball. In this embodiment, eight balls 23 are provided on the same circumference.

The circumferential groove 66 of the rotary drive shaft 13 is formed in such a size that its center angle is an arc of about 45 degrees when viewed in cross section. The round hole 68 is defined by an arcuate wall continuous from the circumferential groove 66, and its height corresponds to a central angle of about 45 degrees. Also the second block 5
The circumferential grooves 69 and 70 of No. 6 are arranged on the inside and outside at an arcuate angle of about 45 degrees, respectively, and the inner circumferential groove 69 has an arcuate surface that is continuous with the circular hole 68 of the holding member 16. Therefore, as shown in FIG. 2, when the attached presser member 16 and cutting member 15 are fitted in the predetermined positions of the rotary drive shaft 13, the ball 23 is inserted into the circumferential groove 66, the round hole 68, and the inner side. It is adapted to fit into a housing portion 65 formed by a circumferential groove 69.

In this state, when the rotary drive shaft 13 rotates while being pulled toward the base end side E and the first block 53 of the cutting member 15 cuts the workpiece, the cutting reaction force is generated as shown by the arrow in FIG. As shown at F, the ball 23 extends from the inner circumferential groove 69 of the second block 56 toward the center of the ball 23 and engages the circumferential groove 66 of the rotary drive shaft 13 . That is, ball 23
is pressed against the rotary drive shaft 13, so that the cutting reaction force F is received by the rotary drive shaft 13.

Further, as shown in FIG. 3, when the cutting member 15 and the holding member 16 are separated in the axial direction, the ball 23 engages with the round hole 68 and moves away from the position of the inner circumferential groove 69 of the second block 56. By moving to the position of the outer circumferential groove 70, it becomes possible to retract radially outward. At this time, when the rotary drive shaft 13 moves relative to the ball 23, the ball 23 moves out of the circumferential groove 66 and is pushed outward in the radial direction by the outer circumferential portion of the rotary drive shaft 13, so that the ball 23 moves outside the second block 56. It will fit into the circumferential groove 70. That is, the edges of the cutting member 15, the holding member 16, and the rotary drive shaft 13 are cut, and the fixation is released.

Next, details of the exchange device 24 will be explained.

As shown in FIGS. 4 and 5, the sliding body 2
A cap member 71 that substantially supports the second arms 28 and 30 is fixed to the tip of the cap member 7 by a bolt 72.
A pin 73 that is slidable in the axial direction is embedded between the cap member 71 and the cylindrical body 25. That is, the cylindrical body 25 and the sliding body 27 are configured to move integrally in the direction of rotation around the axis.

Further, approximately U-shaped engaging members 74 and 75 are attached to the extending ends of the second arms 28 and 30 with bolts 76, and these engaging members 74 and 75 are attached to the holding member 16. , 32 and can be fitted into an engaging groove 59 on the outer periphery of the two. Also attached to the extending ends of the first arms 26, 29 are annular holding members 77, 78 that fit into the holding grooves 58 of the cutting members 15, 31. In this embodiment, the finishing cutting member 15 that is engaged with the rotational drive shaft 13 in the figure is attached to the holding members 77 and 78 of the three first arms 26 and 29, respectively.
A cutting member 79 for semi-finishing and a cutting member 31 for rough finishing, which are replacement cutting members, are held, and holding members 16, 80, and 32 are respectively provided. Furthermore, reinforcing brackets 81 and 82 are appropriately attached to these arms 26, 28, 29, and 30.

In addition, the pressure chamber 41 is divided between a stepped portion 83 formed on the inner wall of the cylinder body 27 and a stepped portion 84 formed in the shape of a piston on the sliding body 27. The air passage 38, which has been extended along the radial direction, is bent in the radial direction and communicated with the pressure chamber 41.

On the other hand, on the proximal end side E of the exchanging device 24, as shown in FIG. , there is a sliding body 27 between them.
A stroke ball bearing 87 is interposed to allow rotation around the axis and allow movement in the axial direction.

Further, as shown in FIG. 7, the portion of the sliding body 27 exposed between the cylindrical body 25 and the base cylinder 36 is
A regulating means 88 for appropriately regulating the position of the turning movement by the air motor 43 is provided, and a position detecting means 89 for confirming the position set by the regulating means 88 is provided.

The regulating means 88 is a boss member 9 that is fitted into the sliding body 27 and has a notch 90 and an identification groove 91 on its outer circumference.
2 and a claw member 93 that is formed to move forward and backward in the radial direction and engages with the notch 90, and the position detection means 89 is configured as a detection sensor (limit switch) 94 that senses the identification groove 91. ing.

The notch 90 and the identification groove 91 are connected to the boss member 92.
The claw member 93 and the sensing portion of the detection sensor 94 are positioned to face these protrusions 95 and 96. Claw member 9
3 is supported by a reciprocating block 98 in a housing 97 attached to the outer wall of the base cylinder 36, and this retracting block 98 is biased toward the housing 97 in the advancing direction (radially inward). That is, a bolt 99 extending in the radial direction is attached to the housing 97.
A reciprocating block 98 is slidably fitted to the distal end of the bolt 99, and a compression spring 100 is also provided. Further, the housing 97 includes a claw member 93.
A regulating bolt 101 is provided to regulate the advancing direction of the holder.

The notches 90 are appropriately provided so that each arm 26, 28, . It consists of being done. Then, the sliding body 27 is rotated in the normal rotation direction G shown in FIG.
When the notch 90 reaches the position of the corresponding notch 90, the detection sensor 94 senses the identification groove 91 formed corresponding to the notch 90. Then, this detection sensor 94 sends a stop and reverse rotation signal to the air motor 43, and the pawl member 9
3 is engaged with the notch 90.

Further, as shown in FIG. 8, the base cylinder 3
6 is provided with a position sensor (proximity switch) 102 for monitoring the movement of the sliding body 27 in the axial direction. This position sensor 102 is connected to an end block 104 provided at the extending end of the sliding body 27 via a bearing 103.
It is attached so that it faces the outer circumferential surface of the This end block 104 is adapted to move integrally with the sliding body 27 in the axial direction, and is appropriately supported with respect to the base cylinder 36 via a pin 105 extending in the axial direction. Relative movement in the direction is allowed. The end block 104 also supports an air pipe 106 connected to an air supply source (not shown) via a bracket 107, and the air pipe 106 is rotatably attached to the other end 39 of the air passage 38. swivel joint 108.

In addition, a plurality of bolts 109 and 110 are provided on the side of the base cylinder 36 for appropriately fixing it to the bracket 37 of the machine body 18.

Furthermore, this cutting machine is equipped with a controller (not shown) for driving and controlling the main shaft 19, and performs desired back counterboring according to a program. Based on the signal, the drive control of the air motor 43 and the air supply timing related to attachment/detachment are controlled.

Next, the operation of the embodiment will be explained.

When performing back counterboring on a workpiece W, such as a hub of a compressor, after the shaft hole 12 has been formed, first, the rotary drive shaft 1 attached to the main shaft 19 of the cutting machine body 18 is
3 is passed through the shaft hole 12 by advancing the main shaft 19, and then the cutting member 15 is attached by the exchange device 24.

Next, the cutting member 15 to be attached is positioned at the tip of the rotary drive shaft 13, and pressurized air is supplied from the air supply source to the air passage 38 to move only the cylindrical body 25 toward the proximal end side E in the axial direction. let The first arm 26 now separates the cutting member 15 it holds from the holding member 16, which is immovably engaged by the second arm 28. Due to this separation, the ball 23 of the attachment/detachment mechanism 17
While being engaged with the round hole 68 of the holding member 16, it is moved to the position of the outer circumferential groove 70 of the third block, and is in a state where it can be retracted radially outward.

Next, by driving the main shaft 19, the rotary drive shaft 13 is rotated at a low speed and advanced toward the tip side D in the axial direction, and the spline 49,
Engage 54. At this time, if the spline fitting is poor and the cutting member 15 and the holding member 16 do not enter the predetermined position of the rotary drive shaft 13 and the sliding body 27 is relatively pressed, the position sensor 102 detects this. Then, a signal is sent to the controller to immediately stop the axial movement of the main shaft 19 and restart the fitting.

When the spline fitting is completed and the cutting member 15 and the holding member 16 are inserted to the predetermined positions, the supply of air is stopped and the pressing member 16 and the cutting member 15 are moved by the urging force of the urging means 22. and attach it. Due to this attachment, the ball 23 of the attachment/detachment mechanism 17 is restrained by the inner circumferential groove 69 of the third block and the round hole 68 of the cutting member 16 and protrudes, and is fitted into the circumferential groove 66 of the rotary drive shaft 13. The cutting member 15 is now in a state in which the rotational drive is transmitted through the spline fitting and is also fixed in the axial direction, and the cutting process is started. Also, the cutting reaction force F at this time is the ball 2
3 and is received by the rotational drive shaft 13 (see Fig. 2).
.

Furthermore, when replacing the attached cutting member 15 with other cutting members 32, 79, air is supplied from the state shown in FIGS. 2 and 4 to move the cylinder body 25 and first arm 26 to the base. The cutting member 15 is moved to the end side E to separate the cutting member 15 from the holding member 16. The ball 23 is now moved from the inner circumferential groove 69 to the outer circumferential groove 70 of the third block and is in a recessed state, and by retracting the rotary drive shaft 13 toward the base end side E, it is moved out of the circumferential groove 66 ( (See Figure 3). With this, the cutting member 15 and the holding member 16 are released from being fixed to the rotary drive shaft 13, and the rotary drive shaft 13 is further retreated to be completely separated.

Next, for example, when attaching the cutting member 31 for rough finishing to the rotary drive shaft 13, the air motor 43 is rotated in the forward direction so as to rotate it by 180 degrees from the state shown in FIG.

Due to this normal rotation, the sliding body 27 is rotated around the axis, and the cylindrical body 25 is also rotated integrally with the sliding body 27, so that the first arms 26, 29 and the second arms 28, 30
is rotated. When the arm 29 holding the cutting member 31 for rough finishing reaches the position of the rotary drive shaft 13,
The detection sensor 94 senses the corresponding identification groove 91 and stops the air motor 43, and then rotates it slightly in the opposite direction to engage the notch 90 with the claw member 93.

Then, in the same manner as described above, the cylinder body 25 is moved by air supply, and the cutting member 31 and the holding member 32 are separated by the first arm 29, so that the ball 23 is brought into a retractable state. After that, the rotary drive shaft 13 is spline-fitted. Then, by releasing the holding of the cutting member 31, the ball 23 is moved into the circumferential groove 6 of the rotation drive shaft 13.
6 and secure it. This makes it possible to perform cutting using the new cutting member 31 for rough finishing.

In this way, the cutting member 15 is spline-fitted to the rotary drive shaft 13 and has the first block 53, which is a milling cutter, on the base end side E thereof, and the tip of the cutting member 15 is Since the back counterboring cutting tool 11 is configured with the holding member 16 provided on the side D and the attachment/detachment mechanism 17 having the ball 23 that can be retracted and retracted by approaching and separating the holding member 16 and the cutting member 15, By slightly sliding the cutting member 15 or the holding member 16, the ball 2
3 is retracted and fixed to the rotary drive shaft 13 or released from the fixation. That is, the milling cutter can be attached and detached extremely easily and quickly compared to the conventional attachment and detachment using nuts.

[0053] In this embodiment, the cutting member 15 is formed by two blocks 53 and 56, but of course they may be formed integrally.

Also, a device 24 for attaching and detaching the cutting tool 11
As shown in FIG. Since the sliding body 27 is formed to be relatively movable and the second arm 28 is supported by the sliding body 27 and extends to engage with the pressing member 16, the sliding body 27 or the cylinder 25 can be moved relative to each other. Cutting member 15 or presser member 1 can be removed by simply moving it.
6 can be slid, and can be fixed to or unfixed to the rotary drive shaft 13 by the attachment/detachment mechanism 17. That is,
It is possible to automatically attach and detach the cutting member 15 and the holding member 16 without having to do it manually by an operator.

Furthermore, this exchange device 24 includes a plurality of first arms 29 that hold the replacement cutting members 31, 79, and a plurality of second arms 29 that engage with the holding members 32, 80 of the replacement cutting members 31, 79. an attachment/detachment driving means 33 for appropriately moving the cylinder 25, and an arm 30 for the cylinder 25 and the sliding body 27.
By controlling these drive means 33 and 34, the cutting member 1 can be rotated.
5 and the presser member 16 can be automatically attached and detached, and can be replaced as necessary. That is, in counterboring using an NC machine tool, labor savings and efficiency improvements can be achieved.

In the above embodiment, the holding member 16 is fixed in position and the cutting member 15 is moved during attachment and detachment, but the holding member 16 may be moved to the distal end side D. Also, both may be moved in opposite directions.

[0057] Furthermore, the number of arms is not limited to three;
It will be increased or decreased as necessary. The extending shape is appropriately formed according to the shape of the workpiece, and therefore, this exchanger can be applied to any workpiece.

[0058]

[Effects of the Invention] In summary, according to the present invention, the following excellent effects are achieved.

(1) According to the structure of claim 1, simply by sliding the cutting member or the holding member, it is fixed to or released from the rotational drive shaft, and the milling cutter can be easily and quickly attached and detached.

(2) According to the second aspect of the present invention, the cutting member and the holding member can be fixed or unfixed simply by relatively moving the sliding body or the cylindrical body, and the attachment and detachment can be automated.

(3) According to the configuration of claim 3, the cutting member and the holding member can be automatically attached/detached and replaced;
Manpower saving and efficiency improvement in cutting work can be achieved through automatic control.

[Brief explanation of the drawing]

FIG. 1 is a side view showing an embodiment of a back counterboring cutting tool and its exchange device according to the present invention.

FIG. 2 is a side sectional view showing a main part of the back counterboring cutting tool of FIG. 1;

FIG. 3 is a side sectional view for explaining the effect of FIG. 2;

FIG. 4 is a partially cutaway side view showing essential parts of the exchange device of FIG. 1;

FIG. 5 is a front view of FIG. 4;

FIG. 6 is a partially cutaway side view showing other main parts of the exchange device of FIG. 1;

7 is a cross-sectional view taken along the line AA in FIG. 6. FIG.

8 is a sectional view taken along the line BB in FIG. 6. FIG.

FIG. 9 is a side view showing a conventional back counterboring cutting tool.

[Explanation of symbols]

11 Cutting tool for back counterboring 12 Shaft hole 13 Rotation drive shaft 14 Milling cutter 15 Cutting member 16 Holding member 17 Attachment/detachment mechanism 21 Seat 23 Ball 24 Exchange device for cutting tool for back counterboring 25 Cylindrical body 26, 29 First Arms 28, 30 Second arms 31, 79 Replacement cutting members 32, 80 Holding member 33 provided on the replacement cutting member Attachment/detachment drive means 34 Swing drive means W Workpiece D Tip side E Base end side

Claims (3)

[Claims] Claim 1: A rotary drive shaft that is inserted into a shaft hole formed in a workpiece so as to be able to move forward and backward; A back counterboring cutting tool having a milling cutter is provided between a cutting member that is spline-fitted to the rotary drive shaft and has the milling cutter on the proximal end side, and a distal end side of the cutting member, and A presser member biased in an approaching direction, and a rotary drive shaft having a ball provided between the presser member and the cutting member that moves in and out of the rotary drive shaft as these members approach and separate. A cutting tool for back counterboring, characterized by being equipped with a mechanism for attaching and detaching the member. 2. A rotary drive shaft that is inserted into a shaft hole formed in a workpiece so as to be able to move forward and backward; In a device for exchanging a back counterboring cutting tool having a milling cutter, the back counterboring cutting tool is a cutting member spline-fitted to the rotational drive shaft and having the milling cutter on the proximal end side. a presser member provided between the presser member and the distal end side of the cutting member and biased toward each other; and a presser member provided between the presser member and the cutting member and the rotation drive shaft as they approach and separate. A mechanism for attaching and detaching the cutting member to the rotary drive shaft having a ball that appears and retracts from the rotary drive shaft, wherein the exchanging device includes a cylindrical body extending parallel to the rotary drive shaft. , a first arm supported by the cylindrical body and extended to hold the cutting member, a sliding body fitted into the cylindrical body and formed to be relatively movable in the axial direction, and a first arm supported by the sliding body. A changing device for a cutting tool for back countersinking, comprising a second arm extending to engage with the holding member. 3. The exchanging device includes a cylindrical body extending parallel to the rotary drive shaft, and a cylindrical body supported by the cylindrical body and extending radially to hold the cutting member and the replacement cutting member. a plurality of first arms, a sliding body fitted into the cylindrical body and formed to be relatively movable only in the axial direction, and a presser supported by the slider and provided on the presser member and the replacement cutting member. a plurality of second arms extending radially to engage with the member; an attachment/detachment drive means for appropriately moving the cylindrical body to cause the first arm to separate the cutting member from the holding member; Claim 2, further comprising a turning drive means for turning the cylindrical body and the sliding body to appropriately position the extending end of the arm at the tip of the rotary drive shaft.
The device for changing the cutting tool for back counterboring described above.