JP3781649B2 - Automatic tool changer - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an automatic tool changer for a machine tool such as a machining center.
[0002]
[Prior art]
Conventionally, there is a vertical or horizontal machining center in which a tool magazine is arranged on the side of a machine. For example, in a vertical machining center described in Japanese Patent No. 3042597, a tool is stored in a horizontal direction via a plurality of tool pots connected to an endless chain, and an arbitrary tool is moved to a tool delivery position by rotating the chain. The tool magazine to be indexed is arranged on the side of the machine to increase the number of tools to be stored in the tool magazine, save the space for the tool magazine, and facilitate the storing of the tool in the tool magazine.
[0003]
[Problems to be solved by the invention]
However, in the vertical machining center disclosed in the above-mentioned patent publication, a tool transfer device must be arranged between the tool magazine and the tool changer, which makes the structure complicated and increases the installation area of the machine. There's a problem. Also in other vertical and horizontal machining centers, some kind of tool transfer device is provided to increase the complexity of the structure and the installation area.
[0004]
An object of the present invention is to solve such problems of the prior art, and an object of the present invention is to provide an automatic tool changer in which the tool changer is reduced in size and simplified in configuration.
[0005]
[Means for Solving the Problems]
To achieve the above object, according to the present invention, in an automatic tool changer that performs tool change between a spindle of a machine tool having a vertical spindle and a tool magazine, the tool is gripped in a downward posture. A tool magazine provided with a plurality of grippers that can be indexed in a horizontal plane, and a tool gripping portion disposed at both ends, and a retreat for exchanging tools with the tool magazine adjacent to the tool magazine A tool exchange arm that swings between a position and an exchange position for exchanging the tool with the tool mounted on the spindle, and the tool exchange arm is rotatably provided at the tip, and the tool exchange arm is retracted. A swing arm that swings and moves the tool change arm between a position and an exchange position, and a fitting portion that can be fitted to a shank portion of the tool when the tool change arm is in the retracted position, horizontally and vertically Move in the direction Grips and a shifter means for transferring the tool to move the tool horizontally between the gripper of the tool magazine and the tool-holding part of the tool change arm, said tool magazine and a tool gripping portion of the tool changing arm There is provided an automatic tool changer comprising drop prevention means having a guide groove for engaging a tool pull-in pull stud provided at a rear portion of the tool during tool transfer with the gripper .
Further, according to the present invention, a hollow shank taper type two-face constrained tool is gripped in a downward posture in an automatic tool changer that performs tool change between a spindle of a machine tool having a vertical spindle and a tool magazine. A tool magazine provided with a plurality of grippers to be indexed in a horizontal plane and a tool gripping portion disposed at both ends, and a tool is exchanged between the tool magazine adjacent to the tool magazine. A tool exchange arm that swings between a retreat position and an exchange position for exchanging the tool with the tool mounted on the spindle, and the tool exchange arm is rotatably provided at a tip portion of the tool exchange arm. A swing arm that swings and moves the tool change arm between a retracted position and an exchange position, and a fitting portion that can be fitted to the shank portion of the tool when the tool change arm is in the retracted position in the horizontal direction and Moved up and down A shifter means for moving the tool horizontally between the tool gripping portion of the tool changer arm and the gripper of the tool magazine to transfer the tool, and a cam rod provided to be movable in the vertical direction A cam groove that engages with the cam rod during the transfer of the tool and lifts the cam rod upward, and engages with a shank of a hollow shank tapered two-surface constraining tool while the cam rod is moving upward. There is provided an automatic tool changer comprising an anti-drop means having an engaging member for holding the tool.
The tool mounting posture on the spindle and the tool storage posture in the tool magazine are the same, and the tool can be changed only by parallel movement without changing the tool posture. In addition, the tool change arm can be moved between a retreat position where tools can be exchanged with the tool magazine and an exchange position where tools can be exchanged with the spindle with a simple movement called swing, and the entire automatic tool changer is compact. And simple structure.
[0006]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings.
First, a first embodiment of the present invention will be described with reference to FIGS.
A machine tool 101 to which the present invention is applied includes a bed 103 installed on a floor surface of a factory or the like, a column 105 erected on the bed 103, a vertical direction (Z-axis direction) and a horizontal left-right direction ( Spindle head 107 reciprocally mounted in the X-axis direction), a pair of guide surfaces 113 extending in the Y-axis direction which is a horizontal direction perpendicular to the X-axis on the bed 103, and reciprocally provided along the guide surfaces 113. Table 111 is included. An automatic tool changer 11 is disposed on one side of the bed 103 and the column 105.
[0007]
In this embodiment, the tool T is a pull stud type tool having a taper shank 27 and a pull stud 27 a for pulling in the tool provided at the rear end of the taper shank 27, and is formed on the large diameter portion of the taper shank 27. It has an engaging portion 28 made of a circumferential groove. In addition, the taper shank 27, the pull stud 27a, and the engaging part 28 may be formed in the tool T itself, or may be provided in a tool holder (not shown) to which the tool T is mounted.
[0008]
The automatic tool changer 11 includes a swing arm 17 that is provided so as to be rotatable about a swing shaft 15 fixed on the upper surface of the base 13. The swing arm 17 serves as a rotary actuator. An air motor 19 is attached. The air motor 19 has a rotating shaft 19a (see FIG. 3) provided vertically, and a tool changing arm 21 is attached to the tip of the rotating shaft 19a. The tool exchange arm 21 is composed of a horizontally disposed plate member, and a tool gripping portion 21a that can engage with the engaging portion 28 of the tool T is provided at a position opposed to the longitudinal direction by 180 °, that is, at both ends. More specifically, the tool gripping portion 21a is formed of an arc-shaped recess having an opening for attaching and detaching the tool T in the horizontal direction, and is a lock formed of an arc-shaped protrusion that engages with the engaging portion 28 of the tool T. It has a portion 21b. Further, in order to prevent the tool T engaged with the tool gripping portion 21a from falling off, the movable claw 20 (biased in the direction of narrowing the opening portion by a spring is provided in the opening portion of the arc-shaped recess. 3) is provided.
[0009]
An air cylinder 23 is attached to the base 13 of the automatic tool changer 11 as a swing actuator that swings the swing arm 17 about the swing shaft 15. A distal end portion of an extendable piston rod 25 connected to a piston (not shown) of the air cylinder 23 is rotatably connected to a tab 17a of the swing arm 17 by a pin 25a. Is rotatably connected to the base 13 by a pin 23a. As shown in FIG. 2, when the piston rod 25 extends, the swing arm 17 and the tool change arm 21 attached to the swing arm 17 swing around the swing shaft 15 and move to the tool change position. To do. At the tool change position, the center axis of the tool T gripped by one tool gripping portion 21a of the tool change arm 21 coincides with the center axis of the main spindle 109 at the tool change position. That is, normally, since the tool mounted on the main shaft 109 is received by an empty tool change arm, the tool gripping portion 21a just engages with the tool mounted on the main shaft 109 when it swings. . On the other hand, when the piston rod 25 moves backward, the swing arm 17 and the tool change arm 21 rotate about the swing shaft 15 and move to the retracted position indicated by the two-dot chain line in FIG. In the retracted position, the tool change arm 21 is in a position where it does not interfere with the main shaft 109 and the tool T attached to the main shaft 109.
[0010]
The automatic tool changer 11 also includes a tool magazine having a plurality of grippers 33. The gripper 33 is connected to a chain 30 that extends horizontally around the pair of pulleys 29 and 31. In this embodiment, one of the pulleys 29 and 31 is connected to a drive motor (not shown), and the pulley 29 rotates so that the gripper 33 circulates in the horizontal plane together with the chain 30. It has become. As understood from FIGS. 1 and 2, the gripper 33 is engaged with the engaging portion of the tool T, and the tool T is suspended and held in the vertical direction with the tip of the tool T directed downward.
[0011]
The automatic tool changer 11 further transfers the tool between one tool gripping portion 21a of the tool changer arm 21 arranged at the retracted position and a gripper 33 that is indexed and arranged at a tool transfer position described later. A shifter 41 is provided. The shifter 41 includes a fitting portion 43 having a tapered hole 43a to be fitted with the taper shank 27 of the tool T, a vertical actuator 45 for moving the fitting portion 43 in the vertical direction, and a horizontal actuator for moving the fitting portion 43 in the horizontal direction. 51. The vertical actuator 45 and the horizontal actuator 51 can be formed by a fluid pressure cylinder, preferably a pneumatic cylinder. The horizontal actuator 51 moves forward and backward in the vertical direction with respect to the chain 30 stretched between the pulleys 29 and 31 in an area adjacent to the tool changing arm 21 in the retracted position. In the present embodiment, the axis O (see FIGS. 1 and 2) parallel to the moving direction of the horizontal actuator 51 passing through the center of the tapered hole 43a of the fitting portion 43 determines the tool transfer position.
[0012]
The shifter 41 includes a horizontally extending beam 47 and a pull stud guide 49 attached to the tip of the beam 47 as drop-off preventing means. The beam 47 and the pull stud guide 49 together with the fitting portion 41 are vertical. It is provided to be movable in the direction. The pull stud guide 49 is positioned in the horizontal direction between one tool gripping portion 21a of the tool changing arm 21 at the retracted position at the tip of the beam 47 and the gripper 33 at the tool transfer position. The pull stud guide 49 is formed with a guide groove 49a that opens downward to allow the pull stud 27a to pass therethrough. The guide groove 49a has a horizontal guide surface 49b that protrudes inward from both measurements and engages with an engagement portion 27b having a large diameter at the tip of the pull stud 27a.
[0013]
Hereinafter, the operation of the present embodiment will be described.
While the machine tool 101 is machining a workpiece (not shown) attached to the table 111, the tool change arm 21 is in the retracted position. At this time, as shown in FIG. 1, a new tool T used in the next process is mounted on the tool gripping portion 21a facing the tool transfer position in the tool change arm 21, and a tool is mounted on the other tool gripping portion 21a. It has not been. When a tool change command is issued from the NC device (not shown) of the machine tool 101, the spindle 109 moves to the tool change position. Next, the air cylinder 23 extends, and the tool change arm 21 swings with the swing arm 17 about the swing shaft 15 and moves to the tool change position. When the tool change arm 21 moves to the tool change position, the tool gripping portion 21a on which the tool is not attached engages with the engagement portion of the tool T attached to the spindle 109 at the tool change position (FIG. 1). reference).
[0014]
Next, after the tool unclamping operation is performed in the main shaft 109, the main shaft 109 moves up in the Z-axis direction, whereby the tool T attached to the tip portion of the main shaft 109 is removed from the main shaft 109. When the tool T is removed from the main shaft 109, the air motor 19 rotates 180 °, and the new tool T held by the tool holding portion 21a of the tool changing arm 21 and the old tool T extracted from the main shaft 109 are replaced. As the main shaft 109 moves downward in the Z-axis direction, the new tool T is mounted on the main shaft 109. Next, a tool clamping operation is performed in the main shaft 109, and the air cylinder 23 contracts. That is, as the piston rod 25 moves backward, the tool change arm 21 swings with the swing arm 17 about the swing shaft 15 and moves to the retracted position.
[0015]
When the tool change arm 21 moves to the retracted position, the old tool T is arranged at a tool transfer position whose center coincides with the axis O. Next, the fitting portion 43 and the pull stud guide 49 are moved up by the vertical actuator 45 of the shifter 41 to a high position where it does not interfere with the pull stud 27 a of the old tool T held by the tool holding portion 21 a of the tool changing arm 21. At this time, the pull stud guide 49 is positioned in the Z-axis direction with respect to the fitting portion 43 so that the guide groove 49a can receive the pull stud 27a of the old tool T at the tool transfer position. Next, the fitting portion 43 is advanced by the horizontal actuator 51 to the advance position where the center of the taper hole 43 a of the fitting portion 43 coincides with the center of the old tool T. Next, the fitting portion 43 and the pull stud guide 49 are moved downward by the vertical actuator 45 to a low position where the tapered hole 43 a is fitted to the tapered shank 27 of the tool T. Next, when the fitting portion 43 is retracted by the horizontal actuator 51, the old tool T is detached from the tool gripping portion 21a and moves horizontally toward the gripper 33 of the tool magazine.
[0016]
During horizontal movement of the old tool T, the pull stud 27b engages with the guide groove 49a. More specifically, the pull stud 27b engages with the engaging portion 27b at the tip of the pull stud 27b and the guide surface 49b extending horizontally, and the guide surface 49b supports the engaging portion 27b from below. 27b moves along the guide groove 49a. Since the guide surface 49b supports the engaging portion 27b from below, the taper shank 27 is prevented from falling out of the tapered hole 43a during horizontal movement, and the old tool T is prevented from falling off.
[0017]
When the fitting part 43 moves backward to the retracted position where the engaging part 28 of the old tool T engages with the gripper 33, the horizontal movement by the horizontal actuator 51 stops, and the fitting part 43 starts to move upward by the vertical actuator 45. To do. As a result, the fitting portion 43 is detached from the tool T while the tool T is held by the gripper 33. Thus, when the engagement between the fitting portion 43 and the tool T is released, the drive motor (not shown) of the pulley 29 rotates, and a new tool used in the next process is indexed to the tool transfer position. The new tool T indexed to the tool transfer position is moved from the gripper 33 toward the tool gripping portion 21a of the tool changing arm 21 according to the procedure opposite to the procedure described above, and is mounted on the tool gripping portion 21a. The tool change arm 21 stands by until the next tool change command is issued in a state where the new tool T is mounted at the retracted position.
[0018]
According to the present embodiment, in the automatic tool changer 11 of the machine tool 101 having the vertical spindle 109, the tool magazine holds the plurality of grippers 33 capable of holding the tool T in a downward posture and indexing in a horizontal plane. The shifter 41 moves the tool T horizontally in the downward posture, and the tool T is moved between the tool change arm 21 at the retracted position adjacent to the tool magazine and the gripper 33 indexed at the tool transfer position. Transport. Then, it swings horizontally between the retracted position and an exchange position for exchanging the tool with the tool T mounted on the spindle 109, and at the tool exchange position, the tool exchange arm 21 is rotated 180 ° horizontally to provide new and old tools. T is replaced and tool exchange with the spindle 109 is performed. As described above, the automatic tool changer according to the present embodiment performs the tool change that changes the direction of the tool T in the downward posture. Therefore, the conventional tool transfer device that transfers the tool while changing the direction of the tool is used. Compared to technology, it becomes a very small automatic tool changer.
[0019]
Further, since the pull stud guide 49 that engages with the pull stud 27a of the tool T that is moving in parallel and supports it from the lower side is provided as means for preventing the tool from falling during tool transfer, it prevents the tool from falling off. In order to achieve a very simple configuration without a clamping mechanism and to reduce the number of actuators required, as compared to the prior art that specifically clamps a tool or a tool pot. Manufacturing costs can be reduced.
[0020]
Next, a second embodiment of the present invention will be described with reference to FIG. In the second embodiment, the method of mounting the tool T on the main shaft is different from that of the first embodiment, and the configuration of the drop-off prevention means is accordingly different. The rest of the configuration is substantially the same as in the first embodiment, and in FIG. 4, the same reference numerals are assigned to the components corresponding to those in FIGS. Further, in the following description, only differences from the first embodiment will be described.
[0021]
In the first embodiment, the tool T is a pull stud type tool having the taper shank 27 and the pull stud 27b, but the present invention is not limited to this. In the second embodiment, the tool T is a two-surface constrained tool having a hollow shank taper called a so-called HSK type. Referring to FIG. 4, the tool T is a two-face constrained tool having this hollow shank taper, and has a hollow shank 61 having an opening at the upper end. The shank 61 is formed with a locking portion 61a that protrudes into the internal space along the edge of the opening.
[0022]
In the second embodiment, the shifter 42 has a fitting portion 63 having a tapered hole 63a that fits the shank 61 of the tool T, and the fitting portion 63 is arranged in the vertical direction as in the first embodiment. And a horizontal actuator 51 for moving the fitting portion 63 in the horizontal direction. The fitting portion 63 further has a through hole 63b extending from the upper surface into the tapered hole 63a, and a hollow cylindrical rod guide 73 is fitted and fixed to the through hole 63b. The rod guide 73 has a hollow front end portion 73a that fits into the hollow portion of the shank 61. The front end portion 73a is formed with a transverse hole 73b extending in the radial direction, and a ball 79 is placed in the transverse hole 73b. It is arranged.
[0023]
A cam rod 75 is slidably disposed in the rod guide 73 in the axial direction. The cam rod 75 has a large-diameter portion 75a at the lower end, and the large-diameter portion 75a has a radius that can contact a ball 79 in the transverse hole 73b and project a part of the ball 79 from the transverse hole 73b. is doing. A cam roller 77 is rotatably attached to the upper end portion of the cam rod 75.
[0024]
The shifter 42 according to the second embodiment further includes a beam 67 extending horizontally and a cam 69 attached to the tip of the beam 67. The beam 67 and the cam 69 together with the fitting portion 63 are vertical. It is provided to be movable in the direction. Similar to the pull stud guide 49 of the first embodiment, the cam 69 is located between one tool gripping portion 21a of the tool changing arm 21 at the retracted position at the tip of the beam 67 and the gripper at the tool receiving / receiving position. Positioned horizontally. The cam 69 has a cam groove 69 a provided so as to be engageable with the cam roller 77 of the cam rod 75.
[0025]
Hereinafter, after the tool change command is issued, the old and new tools T are exchanged between the spindle 109 and the tool change arm 21, and the operation of this embodiment is performed from the time when the tool change arm 21 moves to the retracted position. explain.
[0026]
When the tool changing arm 21 moves to the retracted position, the shifter 42 is moved to a high position where the fitting portion 63 does not interfere with the shank 61 of the old tool T held by the tool holding portion 21a of the tool changing arm 21 by the vertical actuator 45. The fitting part 63 and the cam 69 are moved up. Next, the fitting portion 63 is advanced by the horizontal actuator 51 to the advance position where the center of the tapered hole 63a of the fitting portion 63 coincides with the center of the old tool T. Next, the fitting portion 63 and the cam 69 are moved downward by the vertical actuator 45 to a low position where the tapered hole 63a is fitted to the shank 61 of the old tool T. At this time, the tip 73 a of the rod guide 73 is fitted into the hollow portion of the shank 61.
[0027]
Next, when the fitting portion 63 is retracted by the horizontal actuator 51, the old tool T is detached from the tool gripping portion 21a and moves horizontally toward the gripper 33 of the tool magazine. During this time, the cam roller 77 engages with the cam groove 69a. As shown in FIG. 4, the center of the cam groove 69a bulges upward, and the cam rod 75 is pulled vertically upward during the horizontal movement of the old tool T by the engagement of the cam roller 77 and the cam groove 69a. . As the cam rod 75 moves upward, the large diameter portion 75a of the cam rod 75 comes into contact with the ball 79 in the transverse hole 73b and pushes the ball 79 radially outward along the transverse hole 73b. As a result, a part of the ball 79 protrudes from the transverse hole 73b and engages with the engaging portion 61a protruding into the internal space along the edge of the opening of the shank 61, and the shank 61 is removed from the tapered hole 63a during horizontal movement. It is possible to prevent the fallen old tool T from falling off. That is, in the second embodiment, the cam 69, the cam roller 77, the cam rod 75, and the ball 79 constitute a drop prevention means.
[0028]
The operation after the fitting portion 43 is retracted to the retracted position where the engaging portion 28 of the old tool T is engaged with the gripper 33 is the same as that of the first embodiment.
According to the present embodiment, the cam 69 and the cam rod 75 are engaged with each other during the movement of the tool T, the cam rod 75 is lifted upward, and the ball 79 as an engaging member is moved while the cam rod 75 is moving upward. Since the tool T is engaged with the shank 61 of the tool T to prevent the tool T from falling off, the clamping mechanism is compared with the prior art in which the tool or the tool pot is particularly clamped to prevent the tool from dropping off. The manufacturing cost can be reduced because the number of actuators required can be reduced and the number of actuators can be reduced.
[0029]
In the present embodiment, the tool insertion / removal operation to the spindle 109 before and after the tool exchange arm 21 rotates 180 ° at the tool exchange position is performed by moving the spindle head 107 up and down in the Z-axis direction. 21 may be provided with an actuator that moves up and down, and the spindle head 107 may be moved into and out of the spindle 109 by moving up and down on the tool changer arm 21 side without moving.
Moreover, although this embodiment demonstrated the vertical machining center, this invention is applicable also to the horizontal machining center in which the main axis | shaft was provided in the horizontal direction. That is, the automatic tool changer 11 is placed upright with the base 13 so that the posture of the tool gripped by the gripper 33 is the same as the posture of the tool mounted on the spindle 109. Although the direction in which the gravity acts changes, the individual structure of the automatic tool changer may be basically the same as that of the vertical machining center.
[0030]
【The invention's effect】
As described above, according to the present invention, the tool changing arm is quickly positioned at the retracted position where the tool can be exchanged between the tool changing arm and the tool magazine by simply swinging the tool changing arm. The tool changing arm is quickly positioned at the changing position where the tool can be changed between the tool changing arm and the spindle. Furthermore, tool transfer between the tool magazine and the tool change arm can be performed only by parallel movement without changing the posture of the tool. At this time, there is no risk of dropping by either the pull stud type tool or the hollow shank taper type two-surface constraining tool by the fall prevention means.
With these configurations, the entire tool changer can be reduced in size and the structure can be simplified.
[Brief description of the drawings]
FIG. 1 is a plan view showing an automatic tool changer according to a first embodiment of the present invention together with a machine tool.
FIG. 2 is a perspective view of the automatic tool changer of FIG.
FIG. 3 is an enlarged perspective view of a shifter partially cut away.
FIG. 4 is a perspective view similar to FIG. 3 of a shifter according to a second embodiment of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 11 ... Automatic tool changer 13 ... Base 15 ... Swing shaft 17 ... Swing arm 19 ... Air motor 20 ... Claw 21 ... Tool change arm 21a ... Tool gripping part 23 ... Air cylinder 25 ... Piston rod 27 ... Taper shank 27a ... Pull stud 28 ... engagement portion 33 ... gripper 29 ... pulley 30 ... chain 31 ... pulley 41 ... shifter 42 ... shifter 43 ... fitting portion 45 ... vertical actuator 51 ... horizontal actuator 43a ... taper hole 47 ... beam 49 ... pull stud guide 49a ... guide groove 61 ... hollow shank 61a ... locking part 63 ... fitting part 63a ... taper hole 73 ... rod guide 75 ... cam rod 77 ... cam roller 79 ... ball 101 ... machine tool 103 ... bed 105 ... column 107 ... spindle head 113 ... guide surface 111 ... table T ... tool

Claims (2)

In an automatic tool changer that performs tool change between a spindle of a machine tool having a vertical spindle and a tool magazine,
A tool magazine provided with a plurality of grippers for gripping and storing tools in a downward posture so that they can be indexed in a horizontal plane;
A retraction position that has tool gripping portions disposed at both ends, and that is adjacent to the tool magazine to transfer tools to and from the tool magazine, and a replacement position that performs tool replacement with the tool mounted on the spindle A tool change arm that swings between
A swing arm that is rotatably provided at the tip, and swings and moves the tool change arm between a retracted position and an exchange position of the tool change arm;
When the tool exchange arm is in the retracted position, the tool gripping part of the tool exchange arm and the tool magazine are gripped by moving a fitting part that can be fitted to the shank part of the tool in the horizontal direction and the vertical direction. Shifter means for moving the tool horizontally to and from the gripper for transferring the tool,
A fall prevention means having a guide groove for engaging a tool pull-in pull stud provided at a rear portion of the tool during tool transfer between a tool gripping portion of the tool change arm and a gripper of the tool magazine;
An automatic tool changer characterized by comprising: In an automatic tool changer that performs tool change between a spindle of a machine tool having a vertical spindle and a tool magazine,
A tool magazine provided with a plurality of grippers for gripping and storing a hollow shank taper type two-surface constraining tool in a downward posture, and indexable in a horizontal plane;
A retraction position that has tool gripping portions disposed at both ends, and that is adjacent to the tool magazine and that receives and exchanges tools with the tool magazine, and an exchange position that exchanges tools with the tool mounted on the spindle A tool change arm that swings between
A swing arm that is rotatably provided at the tip, and swings and moves the tool change arm between a retracted position and an exchange position of the tool change arm;
When the tool changer arm is in the retracted position, the tool holding part and the tool magazine of the tool changer arm are gripped by moving the fitting part that can be fitted to the shank part of the tool horizontally and vertically. Shifter means for moving the tool horizontally between the gripper and transferring the tool,
A cam rod provided so as to be movable in the vertical direction, a cam groove that engages with the cam rod during the transfer of the tool and lifts the cam rod upward, and a hollow shank taper type while the cam rod is moving upward A fall prevention means having an engagement member that engages with the shank of the two-surface constraining tool and grips the tool;
An automatic tool changer characterized by comprising:

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