JP2013202698A - Tool changer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a tool changer capable of shortening wait time for orientation of a positioning key to a key groove.SOLUTION: In a tool changer, in a case in which a main shaft head is moved to an ATC region, a delivery of a tool holder is performed between a main shaft and a gripping part 63 of a grip arm. The gripping part 63 includes a pair of support pins 76 for pinching side surfaces of the tool holder, and a positioning key 100 which is inserted in a key groove 7f formed on the side surface of the tool holder. A key width at an end part that is inserted in the key groove 7f of the positioning key 100 is changed to a first width before delivery of the tool holder, then it is changed to a second width after the delivery of the tool holder.

Description

  The present invention relates to a tool changer in which a tool magazine having a plurality of tool holding portions is rotatably provided.

  2. Description of the Related Art Conventionally, a machine tool that can perform various types of machining such as “thread cutting”, “drilling”, and “spot facing” on a workpiece in a single apparatus is known. Such a machine tool is provided with a tool changer (ATC). The tool changer includes a tool magazine that stores a large number of tools such as taps and drills in a predetermined storage location in advance. The tool magazine is rotatable with a plurality of grip arms radially. The plurality of grip arms automatically select a desired tool and replace it with a tool that has been processed (see, for example, Patent Document 1).

  A tool holder on which a tool used for processing a workpiece is mounted is held by a gripping portion provided at the tip of the grip arm. At the time of tool change during machining, the spindle head moves up to a predetermined position (Z-axis origin), and a tool holder on which a used tool is mounted is held by a grip arm. Further, the spindle head is raised, and the tool holder with the used tool is removed from the spindle. Next, the tool magazine rotates, and the grip arm that holds the tool holder on which the tool to be used next is moved moves immediately below the spindle. Then, the spindle head descends in the vertical direction, and a tool holder equipped with a tool to be used next is inserted into the spindle.

JP 2006-305663 A

  Generally, a tool holder is formed with a keyway. When the tool holder is held by the gripping portion of the grip arm, it is necessary to securely fit the keyway into the positioning key provided in the gripping portion in order to prevent the tool holder from being displaced. Therefore, when holding the tool holder on which the used tool is mounted by the grip arm, it is necessary to orient (align) the key groove with respect to the positioning key. Until the orientation of the keyway relative to the positioning key is completed, the tool holder cannot be transferred from the spindle to the grip arm, and a waiting time due to this orientation occurs.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a tool changer capable of shortening an orientation waiting time for a positioning key in a keyway.

  A tool changer according to an aspect of the present invention includes a spindle head that rotatably supports a spindle of a machine tool, a machining area that performs a machining operation on a workpiece, and a tool exchange area that performs a tool exchange operation. A column that movably supports the spindle head, a support member that is fixed to the column and that rotatably supports a magazine body that is rotatably indexed about a single axis, and a radially outer periphery of the magazine body A plurality of grip arms having a gripping portion at the tip for gripping a tool holder on which the tool is mounted and the tip and the rear end of the grip arm are pivotally supported and fixed to the outer periphery of the magazine body In the tool changer provided with the fulcrum stand, when the spindle head is moved to the tool change area, the grip portion of the grip arm positioned at a predetermined index position The tool holder is transferred to and from the main shaft, and the gripping portion is fitted into a pair of holding portions that hold the side surface of the tool holder and a key groove that is a recess formed on the side surface of the tool holder. A positioning key, wherein the positioning key has a width of at least an end portion fitted in the key groove between a first width that is less than the formation width of the recess and a second width that is wider than the first width. The width of the end is changed to the first width before delivery of the tool holder, while the width of the end is changed to the second width after delivery of the tool holder. Is done.

  In the tool changer of this aspect, the spindle head that rotatably supports the spindle is supported by the column so as to be movable between the machining area and the tool exchange area. A magazine body provided with a plurality of grip arms is rotatably supported by a support member fixed to the column. A grip arm having a grip at the tip is pivotally supported by a fulcrum base fixed to the outer periphery of the magazine body. When the spindle head is moved to the tool change area, the tool holder is transferred between the spindle and the gripping portion of the grip arm. The gripping portion includes a pair of clamping portions that clamp the side surface of the tool holder, and a positioning key that is fitted in a key groove formed on the side surface of the tool holder. The width of the end portion fitted in the key groove of the positioning key is changed to a first width that is less than the formation width of the key groove before delivery of the tool holder, but is wider than the first width after delivery of the tool holder. It is changed to the second width.

  Thereby, it is easy to fit the positioning key into the key groove before delivery of the tool holder, and the positioning key can be securely fixed to the key groove after delivery of the tool holder. As a result, the positioning key can be securely fixed to the key groove without performing the orientation of the key groove with respect to the positioning key with high accuracy as in the prior art. As a result, the orientation waiting time for the positioning key in the keyway can be shortened.

  The positioning key includes a switch portion that is pressed by the spindle head when the spindle head is in the tool change area, and is separated from the spindle head when the spindle head is in the machining area, When the part is pressed by the spindle head, the width of the end is changed to the first width, and when not pressed by the spindle head, the width of the end is changed to the second width. May be. In this case, when the tool holder is transferred between the spindle and the grip arm gripping part, the spindle head presses the switch part in the tool change area, so that the end of the positioning key fitted into the key groove of the positioning key By changing the width to the first width, the positioning key can be easily fitted in the key groove.

  The positioning key includes a pair of plate-like members that are fitted in the key groove and are arranged to face each other with the switch portion interposed therebetween, and an elastic member that biases the pair of plate-like members toward the switch portion. When the switch portion is pressed, the first diameter portion that holds the interval width of the pair of plate-like members at the first width, and when the switch portion is not pressed, the interval width is set to the second width. You may provide the 2nd diameter part hold | maintained at the width | variety. In this case, the width of the end portion fitted in the key groove of the positioning key can be changed with a simple structure in which the pair of plate-like members open and close depending on whether or not the switch portion is pressed.

1 is a longitudinal sectional view showing main parts of a machine tool 1 and a tool changer 2. FIG. 3 is a perspective view showing a positional relationship among a grip arm 60, a movable cam 28, and a fixed cam 29. FIG. It is a front view of the tool holder. It is the rear view to which the positioning key 100 of the open state was expanded. It is the top view to which the positioning key 100 of the open state was expanded. It is the rear view to which the positioning key 100 of the closed state was expanded. It is the top view to which the positioning key 100 of the closed state was expanded.

  A tool changer 2 according to an embodiment of the present invention will be described with reference to the drawings. In the following description, the left side of FIG. 1 is the front side of the machine tool 1, the right side is the rear side of the machine tool 1, the front side of the paper is the right side of the machine tool 1, and the depth side of the paper is the left side of the machine tool 1.

  With reference to FIG. 1, the structure of the machine tool 1 is demonstrated roughly. The machine tool 1 includes a base (not shown) serving as a base, a columnar column 10 erected on the upper rear side of the base, a spindle head 24 supported so as to be movable up and down along the front surface of the column 10, and a spindle head The main shaft 30 is rotatably supported inside 24 and the tool changer 2 that automatically changes the tool 5 attached to the main shaft 30 is mainly configured.

  Frames 18 (only one frame 18 is shown in FIG. 1) are provided on the left and right side surfaces of the column 10 so as to extend forward with the spindle head 24 sandwiched therebetween. A magazine support base 37 is fixed to the front end portions of the pair of frames 18. The magazine main body 41 of the tool changer 2 is supported on the magazine support base 37. A magazine cover 19 having a substantially L-shaped cross section for covering and protecting the magazine main body 41 is fixed to the upper portion of the magazine support base 37 so as to extend obliquely forward toward the front side of the machine tool 1.

  A servo motor 22 for rotating the spindle 30 is fixed to the upper part of the spindle head 24. On the base, a table device (not shown) that holds the workpiece movably in the XY directions is installed. In the machine tool 1, the spindle head 24 moves up and down, and the tool 5 attached to the tool holder 7 mounted on the spindle 30 that rotates at high speed comes into contact with the workpiece. Apply. Specifically, the machining operation for the workpiece is performed in a machining area below the position of the spindle head 24 (Z-axis origin position) shown in FIG. Further, the tool 5 is exchanged in a tool exchange area (ATC area) above the Z-axis origin position.

  The raising / lowering mechanism of the spindle head 24 will be described. On the front surface of the column 10, a ball screw 12 extending in the vertical direction is rotatably supported by an upper bearing portion 14 and a lower bearing portion 15. The ball screw 12 is screwed through the nut 13 fixed to the back surface of the spindle head 24. The upper end portion of the ball screw 12 is coupled to a drive shaft of a servo motor (not shown) fixed to the upper portion of the upper bearing portion 14 via a coupling (not shown). The ball screw 12 is rotated in both forward and reverse directions by driving of a servo motor. When the ball screw 12 rotates in the forward / reverse direction, the spindle head 24 connected to the nut 13 moves up and down as the nut 13 screwed to the ball screw 12 moves up and down.

  The internal structure of the spindle head 24 will be described. A main shaft 30 having a rotation shaft in the vertical direction is rotatably supported inside the front lower portion of the main shaft head 24. The main shaft 30 is connected via a coupling 23 to a drive shaft of a servo motor 22 fixed to the upper portion of the main shaft head 24. The main shaft 30 is rotated by the rotational drive of the servo motor 22. A tapered hole 31 for mounting a taper mounting portion 7a described later is provided at the tip (lower end) of the main shaft 30. When the taper mounting portion 7 a is mounted in the taper hole 31, a pull stud 7 b described later is clamped (clamped) by a holder clamping member 32 provided inside the main shaft 30. When the holder holding member 32 is pressed downward by a draw bar 34 that is coaxially inserted into a hole passing through the center of the main shaft 30, the clamp of the pull stud 7 b by the holder holding member 32 is released. The

  A crank lever 20 that is substantially L-shaped when viewed from the right side is pivotally supported via a support shaft 21 inside the upper rear portion of the spindle head 24. The crank lever 20 includes a vertical lever 20b extending in the vertical direction and a horizontal lever 20a extending substantially horizontally from the lower end of the vertical lever 20b toward the front. The front end portion of the horizontal lever 20 a can be engaged with a pin 35 that protrudes perpendicularly to the draw bar 34. A plate cam body 36 is fixed to the upper back of the vertical lever 20b. The plate cam body 36 can be brought into and out of contact with the cam follower 17 fixed to the upper bearing portion 14. A tension coil spring (not shown) is elastically interposed between the vertical lever 20b and the spindle head 24. When the crank lever 20 is viewed from the right side, the crank lever 20 is always urged clockwise, so that the downward pressing of the pin 35 by the horizontal lever 20a is always released.

  For example, in a state where the taper mounting portion 7 a of the tool holder 7 is mounted in the taper hole 31 of the main shaft 30, when the main shaft head 24 rises, the plate cam body 36 provided on the crank lever 20 slides on the cam follower 17. In this case, the crank lever 20 rotates counterclockwise around the support shaft 21 when viewed from the right side. Accordingly, the horizontal lever 20 a is pressed downward while engaging the pin 35, so that the holder holding member 32 is biased downward via the draw bar 34. Therefore, the holding of the pull stud 7b by the holder holding member 32 is released. Thereby, the tool holder 7 holding the tool 5 is detachably attached to the main shaft 30.

  The structure of the tool changer 2 will be described. The tool changer 2 includes a cylindrical magazine body 41 with a hook and a plurality of grip arms 60 (in FIG. 1, two upper and lower grips) provided radially along the outer periphery of the back surface of the collar portion 42. Only the arm 60 is shown). A support shaft 45 extending obliquely downward toward the front side of the machine tool 1 is rotatably supported on the magazine support 37 fixed to the frame 18. A magazine body 41 is externally attached to the support shaft 45. Thereby, the magazine main body 41 is disposed in front of the machine tool 1 with the front surface of the circular flange 42 facing the front, and is rotatably supported.

  The magazine body 41 will be described. The magazine body 41 is mainly composed of a cylindrical boss portion 43 into which the support shaft 45 is inserted, and a flange portion 42 provided in a hook shape on the front end side of the outer peripheral surface of the boss portion 43. An indexing disk 47 centered on the support shaft 45 is fixed by being attached to the rear end portion of the boss portion 43. Roller-shaped cam followers (not shown) are provided on the back side of the indexing disc 47 (the surface facing the spindle head 24) corresponding to the positions where the plurality of grip arms 60 are provided.

  A casing 51 is fixed to the upper part of the magazine support 37. A servo motor 50 for rotational indexing of the magazine body 41 is fixed to the upper part of the casing 51. Inside the casing 51, a part of a rotary indexing mechanism including a plurality of gears (not shown) and a cam (not shown) is connected to the rotation shaft of the servomotor 50. A plurality of cam followers of the indexing disc 47 are sequentially fitted into cam grooves (not shown) formed in the cam of the rotary indexing mechanism. Thus, the indexing disc 47 can perform intermittent indexing rotation, and one of the plurality of grip arms 60 can be indexed and positioned at the lowermost end of the magazine body 41. Although not shown, an encoder connected to a control device (not shown) of the machine tool 1 is fixed to the servo motor 50. In the machine tool 1, the rotation index position of the magazine body 41 is controlled by performing feedback control of the servo motor 50 based on the output signal of the encoder.

  The structure of the grip arm 60 will be described with reference to FIGS. 1 and 2. As shown in FIG. 1, a plurality of grip arms 60 (for example, 14) are fixed to the outer peripheral side of the back surface of the collar portion 42 of the magazine body 41 in the circumferential direction at a required central angle.

  As shown in FIG. 2, the grip arm 60 uses a fulcrum base 62 fixed to the outer peripheral side of the back surface of the collar portion 42 of the magazine main body 41 as a fulcrum of the swing operation. The grip arm 60 is pivotally supported via a support shaft 67 provided on the fulcrum table 62. The grip arm 60 mainly includes an arm main body 61 extending in a substantially L shape, a gripping portion 63, and a cam follower support portion 65. The grip portion 63 is provided in a Y-shape on the distal end side that is the free end of the arm main body 61, and can hold the tool holder 7. The cam follower support portion 65 is provided so as to protrude from the portion supported by the support shaft 67 on the rear end side of the arm main body 61 toward the spindle head 24 side, and rotatably supports the cam follower 66.

  The fulcrum table 62 includes a substantially plate-like fixing portion 62 a fixed to the magazine body 41 and a shaft supporting portion 62 b that extends obliquely from the lower portion of the fixing portion 62 a and supports the support shaft 67. The fixing portion 62a is provided with a fixing hole penetrating in the thickness direction of the fixing portion 62a, and corresponds to the fixing holes arranged in the outer periphery of the collar portion 42 of the magazine main body 41. The fulcrum base 62 is fixed to the magazine body 41 by fixing the fixing holes of the fixing portion 62a with bolts in accordance with the fixing holes arranged on the outer periphery of the flange portion 42. Thereby, the entire grip arm 60 can be fixed to the magazine body 41.

  The gripping portion 63 includes a non-open / close type bifurcated portion 69 for holding a V groove 7e (see FIG. 3) described later, and a pair of support pins 76 provided at the inner end of the bifurcated portion 69. ing. The tool holder 7 can be attached to and detached from a substantially circular opening region (tool mounting opening) surrounded by the bifurcated portion 69. The support pin 76 is accommodated so as to be elastically retractable by a compression coil spring (not shown). Cam followers 75 each having the center of the support pin 76 as the center of rotation are provided on the outer sides of the ends divided on both sides of the bifurcated portion 69. The cam follower 75 slides along the cam surface 29a of the fixed cam 29 provided at the tip end (lower end) of the spindle head 24, thereby gripping the V-groove 7e of the tool holder 7 attached to the spindle 30. Guide 63 correctly. When the bifurcated portion 69 of the guided gripping portion 63 is aligned with the V-groove 7e, the pair of support pins 76 are inserted into and abutted with the V-groove 7e, and retracted while pushing back the compression coil spring, whereby the tool holder 7 Is held by the gripping portion 63.

  The cam follower 66 slides along the cam surface 28 a of the movable cam 28 fixed to the front surface of the spindle head 24. The movable cam 28 is pivotally supported by the spindle 25 on the front surface of the spindle head 24. A compression coil spring (not shown) is disposed between the movable cam 28 and the spindle head 24, and the movable cam 28 is supported in an elastically floating state. When the cam follower 66 slides on the cam surface 28 a of the movable cam 28, the arm body 61 swings around the support shaft 67. Thus, the cam follower 75 provided at the end of the bifurcated portion 69 is elastically pressed toward the cam surface 29a of the fixed cam 29 provided at the tip of the spindle head 24.

  Thus, in the tool changer 2, the spindle head 24 is moved up and down, and one of the plurality of grip arms 60 indexed to the lowest position of the magazine main body 41 by using the cam mechanism described above. Only the grip arm 60 is swung. That is, the grip portion 63 of the grip arm 60 at the index position moves between a “proximity position” that is close to the main shaft 30 and a “retraction position” that is separated from the main shaft 30.

  Further, in the gripping portion 63, a recess 80 is formed at the base of the bifurcated portion 69 that is divided on both sides, and is cut out from the tool mounting opening of the bifurcated portion 69 toward the arm body 61. In the grip arm 60 at the index position, the concave portion 80 is formed in a U shape that opens toward the tool mounting opening in a plan view. In an internal space formed by the bottom wall 81 and the side wall 82 (see FIGS. 4 and 6) of the recess 80, a positioning key 100 for fixing a key groove 7f (see FIG. 3) described later is provided. Details will be described later.

  The tool holder 7 will be described with reference to FIG. The tool holder 7 is integrally formed with a taper mounting portion 7a (taper shank portion) which is a main body portion thereof, a 7b pull stud 7b integrally formed at one end portion of the taper mounting portion 7a, and the other end portion of the taper mounting portion 7a. And a collet chuck 7d for attaching the tool 5 to the hook-like portion 7c. An annular V-shaped groove 7e to be held by the grip arm 60 and a pair of key grooves 7f are recessed in the bowl-shaped portion 7c.

  The positioning key 100 will be described with reference to FIGS. In the following description, the positional relationship of the positioning key 100 (and each member constituting the positioning key 100) will be described with reference to the case where the grip arm 60 is in the index position. The positioning key 100 includes a pair of plate-like members (first plate 101, second plate 102), a support shaft 103, a switch unit 104, and a pair of elastic members (first spring 105, second spring 106).

  The first plate 101 and the second plate 102 are disposed to face each other in the recess 80, and face the left and right direction (up and down direction in FIGS. 5 and 7) in plan view. The front end portions (left end portions in FIGS. 5 and 7) of the first plate 101 and the second plate 102 are connected by a support shaft 103 erected in the recess 80 and are rotatably supported by the support shaft 103. The The rear ends (the right ends in FIGS. 5 and 7) of the first plate 101 and the second plate 102 slightly protrude from the recess 80 toward the tool mounting opening.

  Between the first plate 101 and the second plate 102, a rod-shaped switch unit 104 extending upward from the inside of the recess 80 is provided. The switch part 104 has a plurality of shaft parts (small diameter part 104a, taper part 104b, large diameter part 104c) having different diameters and a cylindrical part 104d into which the large diameter part 104c is inserted. The small diameter portion 104a has the smallest diameter at the shaft portion of the switch portion 104 and the longest shaft length. The tapered portion 104b is connected to the lower side of the small-diameter portion 104a and has a tapered shape with a diameter gradually increasing downward. The large diameter portion 104 c is connected to the lower side of the tapered portion 104 b and has the largest diameter at the shaft portion of the switch portion 104. The cylindrical portion 104d is provided on the bottom wall 81 of the recess 80, and holds the cylindrical portion 104d so as to be able to advance and retreat, and supports the shaft portion of the switch portion 104 in an upright state. A compression coil spring (not shown) is provided inside the cylindrical portion 104d, and the large diameter portion 104c is constantly urged from below.

  A first spring 105 is interposed between the first plate 101 and the side wall 82. The first spring 105 constantly biases the first plate 101 toward the switch unit 104. A second spring 106 is interposed between the second plate 102 and the side wall 82. The second spring 106 constantly biases the second plate 102 toward the switch unit 104. Thus, since the 1st board 101 and the 2nd board 102 are pressed by the switch part 104, according to the magnitude | size of the shaft diameter of the switch part 104 which each contacts, the 1st board 101 and the 2nd board A “key width” that is a distance between the free end 102 and the free end (rear end) is determined.

  As shown in FIG. 4 and FIG. 5, in a state where the switch portion 104 is not applied with an external force from above, the large diameter portion 104 c moves upward in the cylindrical portion 104 d, so It moves to the ascending position with the largest protrusion width. When the switch portion 104 moves to the raised position, the large diameter portion 104c becomes a height position sandwiched between the first plate 101 and the second plate 102. Since the 1st board 101 and the 2nd board 102 are hold | maintained in the attitude | position which contacted the large diameter part 104c with a large shaft diameter at this time, the positioning key 100 will be in an open state with the largest key width.

  As shown in FIGS. 6 and 7, when an external force is applied to the switch portion 104 from above, the large diameter portion 104c moves downward along the tapered portion 104b as it moves downward in the cylindrical portion 104d. The distance between the first plate 101 and the second plate 102 is reduced. Further, when the switch portion 104 moves to the lowered position where the protrusion width from the recess 80 is the smallest, only the small diameter portion 104 a is sandwiched between the first plate 101 and the second plate 102. At this time, since the first plate 101 and the second plate 102 are held in a posture in contact with the small-diameter portion 104a having a small shaft diameter, the positioning key 100 is in a closed state with the smallest key width.

  The key width (second width) of the positioning key 100 in the open state is wider than the key width (first width) of the positioning key 100 in the closed state. As an example, the first width may be less than 97% of the formation width of the key groove 7f, and the second width may be 97% or more of the formation width of the key groove 7f. The key width of the conventional positioning key is 97% of the formation width of the key groove 7f.

  With reference to FIGS. 4-7, the relationship between the tool change operation performed with the tool change apparatus 2 and the opening / closing operation | movement of the positioning key 100 is demonstrated. At the time of tool change, the spindle head 24 located in the machining area moves to the Z-axis origin position (see FIG. 1). At this time, the grip arm 60 at the index position moves from the retracted position to the close position as described above. Further, in the grip arm 60 at the index position, the lower end surface of the spindle head 24 presses the protruding end of the switch portion 104 (specifically, the upper end portion of the small diameter portion 104a). Therefore, the positioning key 100 changes from the open state to the closed state, and the key width is reduced from the second width to the first width.

  When the spindle head 24 reaches the Z-axis origin position, in the grip portion 63 of the grip arm 60, the tool holder 7 to which the used tool 5 is attached is fitted into the tool mounting opening of the bifurcated portion 69, and the pair of support pins 76 are It is locked to the V-groove 7e by the spring force. Further, in the positioning key 100 in the closed state, the free end sides of the first plate 101 and the second plate 102 are inserted into the key groove 7f (see FIG. 7).

  After that, while the spindle head 24 moves up in the ATC region from the Z-axis origin position, in the grip arm 60 at the index position, the lower end surface of the spindle head 24 is separated from the protruding end of the switch unit 104. Changes from closed to open. As a result, the key width increases from the first width to the second width, and the positioning key 100 is fixed in the key groove 7f (see FIG. 5). Further, as the spindle head 24 moves up in the ATC region, the holder holding member 32 presses the draw bar 34 to release the clamp on the pull stud 7b. As a result, the tool holder 7 held by the grip portion 63 of the grip arm 60 is extracted downward from the main shaft 30.

  Next, the magazine body 41 rotates, and the grip arm 60 holding the tool holder 7 to which the tool 5 used in the next workpiece machining is held is positioned at the index position. Thereafter, while the spindle head 24 descends in the ATC region toward the Z-axis origin position, the lower end surface of the spindle head 24 presses the protruding end of the switch unit 104 in the grip arm 60 at the index position. Therefore, the positioning key 100 is changed from the open state to the closed state, the key width is reduced from the second width to the first width, and the key groove 7f is not fixed by the positioning key 100 (see FIG. 7).

  Further, as the spindle head 24 descends in the ATC region, the tool 5 used in the next workpiece machining is inserted into the spindle 30 from below, and the holder holding member 32 interrupts the pressing of the draw bar 34. The tool 5 is mounted on the main shaft 30 by clamping the pull stud 7b. Thereafter, as the spindle head 24 descends in the descending region from the Z-axis origin position, the grip arm 60 at the index position moves from the proximity position to the retracted position. In the descending region, workpiece machining is performed using a new tool 5.

  In the above-described tool change operation, when the tool holder 7 on which the used tool 5 is mounted is transferred to the grip arm 60 (that is, when the spindle head 24 located in the machining area is moved to the Z-axis origin position), the keyway Control for orienting 7f with respect to the positioning key 100 is executed before the spindle head 24 is lowered. In the present embodiment, when the positioning key 100 is fitted into the key groove 7f, the positioning key 100 changes from the open state to the closed state, so the free end side of the first plate 101 and the second plate 102 is placed on the key groove 7f. (See FIG. 7). Furthermore, after the positioning key 100 is fitted into the key groove 7f, the positioning key 100 changes from the closed state to the open state, so that the free end sides of the first plate 101 and the second plate 102 are securely within the key groove 7f. (See FIG. 5). Therefore, the positioning accuracy required for the above-described orientation control can be suppressed as compared with the conventional case, and the processing time required for the orientation control can be shortened.

  As described above, in the tool changer 2 according to the present embodiment, the spindle head 24 that rotatably supports the spindle 30 is supported by the column 10 so as to be movable between the machining area and the ATC area. A magazine main body 41 provided with a plurality of grip arms 60 is rotatably supported by a magazine support 37 fixed to the column 10. A fulcrum base 62 fixed to the outer periphery of the magazine body 41 supports a grip arm 60 having a gripping portion 63 at the tip. When the spindle head 24 is moved to the ATC region, the tool holder 7 is transferred between the spindle 30 and the grip portion 63 of the grip arm 60. The grip portion 63 includes a pair of support pins 76 that sandwich the side surface of the tool holder 7 and a positioning key 100 that is fitted into a key groove 7 f formed on the side surface of the tool holder 7.

  The key width of the end portion fitted in the key groove 7f of the positioning key 100 is changed to the first width before the tool holder 7 is transferred, and is changed to the second width after the tool holder 7 is transferred. Thus, the positioning key 100 can be easily fitted into the key groove 7f before the tool holder 7 is delivered, and the positioning key 100 can be reliably fixed to the key groove 7f after the tool holder 7 is delivered. As a result, the positioning key 100 can be reliably fixed to the key groove 7f without performing the orientation of the key groove 7f with respect to the positioning key 100 with high accuracy as in the prior art. As a result, the orientation waiting time for the positioning key 100 in the keyway 7f can be shortened.

  When the tool holder 7 is transferred between the spindle 30 and the gripping portion 63 of the grip arm 60, the key width is changed from the second width to the first width by the spindle head 24 pressing the switch portion 104 in the ATC region. The positioning key 100 can be easily fitted into the key groove 7f. Further, the key width can be changed with a simple structure in which the first plate 101 and the second plate 102 are opened and closed depending on whether or not the switch unit 104 is pressed.

  In the above embodiment, the magazine support base 37 corresponds to the “support member” of the present invention. The pair of support pins 76 corresponds to “a pair of sandwiching portions” of the present invention. The first plate 101 and the second plate 102 correspond to “a pair of plate members” of the present invention. The first spring 105 and the second spring 106 correspond to the “elastic member” of the present invention. The small diameter portion 104a corresponds to the “first diameter portion” of the present invention. The large diameter portion 104c corresponds to the “second diameter portion” of the present invention.

  Needless to say, the tool changer of the present invention is not limited to the above embodiment, and various modifications are possible. For example, in the above embodiment, compression coil springs are exemplified as the first spring 105 and the second spring 106, but a plate spring, a torsion coil spring, or the like may be used.

DESCRIPTION OF SYMBOLS 1 Machine tool 2 Tool changer 5 Tool 7 Tool holder 7e V groove 7f Key groove 10 Column 24 Spindle head 30 Spindle 37 Magazine support base 41 Magazine main body 60 Grip arm 63 Grip part 76 Support pin 100 Positioning key 101 First plate 102 First Double plate 104 Switch portion 104a Small diameter portion 104c Large diameter portion 105 First spring 106 Second spring

Claims (3)

A spindle head that rotatably supports a spindle of a machine tool, a column that movably supports the spindle head between a machining area that performs a machining operation on a workpiece and a tool exchange area that performs a tool exchange operation; A support member that rotatably supports a magazine body that is fixed to a column and that can be rotated and indexed about one axis, and a tool holder that is radially provided on the outer periphery of the magazine body and on which the tool is mounted. A tool changer comprising: a plurality of grip arms each having a grip portion to be gripped; and a fulcrum base that is pivotally supported between the tip and rear ends of the grip arm and fixed to the outer periphery of the magazine body. ,
When the spindle head is moved to the tool change area, the tool holder is transferred between the gripping part of the grip arm located at a predetermined index position and the spindle,
The gripping portion includes a pair of sandwiching portions that sandwich the side surface of the tool holder, and a positioning key that is fitted into a key groove that is a recess formed on the side surface of the tool holder,
In the positioning key, at least a width of an end portion fitted in the key groove can be changed between a first width that is less than a formation width of the key groove and a second width that is wider than the first width. The width of the end is changed to the first width before delivery of the tool holder, and the width of the end is changed to the second width after delivery of the tool holder. A tool changer. The positioning key includes a switch unit that is pressed by the spindle head when the spindle head is in the tool change area, and separated from the spindle head when the spindle head is in the machining area,
When the switch portion is pressed by the spindle head, the width of the end portion is changed to the first width, and when the switch portion is not pressed by the spindle head, the width of the end portion is changed to the second width. The tool changer according to claim 1, wherein the tool changer is changed to: The positioning key is
A pair of plate-like members that are fitted in the key groove and are arranged opposite to each other with the switch portion interposed therebetween;
An elastic member that urges the pair of plate-shaped members toward the switch portion;
When the switch portion is pressed, the first diameter portion that holds the interval width of the pair of plate-like members at the first width, and when the switch portion is not pressed, the interval width is set to the second width. The tool changer according to claim 2, further comprising a second diameter portion held on the tool.

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