JP2008049403A - Machine tool - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a machine tool with a tool magazine capable of easily exchanging a grip arm without entirely removing the tool magazine. <P>SOLUTION: At a machining center, a clevis fixing a grip arm 60 of a tool magazine 40 to be rockable is fixed on an outer periphery of a back face of a collar part 42 of a magazine base 41. Then, screws 80 screwed with a fixing hole of the collar part 42 and a fixing hole of the clevis are mounted from a front side of the collar part 42. Therefore, when the grip arm 60 is removed from the magazine base 41, if a pair of screws 80, 80 fixing the clevis of the grip arm 60, which is an object to be exchanged, are removed from the front side of the collar part 42, only the grip arm 60 can be removed without entirely removing the magazine base 41. Thus, the grip arm 60 can be quickly and easily exchanged. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a machine tool, and more particularly, to a machine tool including a tool magazine in which a grip arm can be removed from a magazine body.

  2. Description of the Related Art Conventionally, a machine tool that can perform various processes such as “thread cutting”, “drilling”, “spot face” and the like on a workpiece in a complex manner with a single device is known. Such a machine tool stores a large number of tools such as taps and drills in a predetermined storage location in advance, selects a desired tool in a timely manner, and automatically replaces it with a tool that has been machined (ATC). It has. Various types of such tool changers have been proposed. For example, a cam mechanism is used between a tool magazine fixed to a frame by moving the spindle head in the vertical direction (Z-axis direction). A machine tool provided with a tool changer that performs tool change is known (for example, see Patent Document 1). In the tool changer of this machine tool, only the grip arm that is indexed for rotation swings with respect to the main shaft.

  For example, like the conventional tool magazine 140 shown in FIG. 9, the clevis 162 is screwed on the back side of the magazine base 141 serving as the main body of the tool magazine 140 at a required central angle in the circumferential direction around the support shaft. Are fixed sequentially. The arm body 161 of the grip arm 160 is pivotally supported by the plurality of clevises 162 via a pivot shaft 167 so as to be swingable. Further, a grip 163 for gripping the tool holder is provided at the free end of the arm body 161. A roller-like cam follower 166 is rotatably supported at a position close to the pivot shaft 167 that serves as a pivot point of the arm main body 161. And the cam follower 166 can contact | abut with the inclined surface of the cam body provided in the front surface of the spindle head. With such a structure, the cam follower 166 of the grip arm 160 slides in contact with the cam body by the reciprocating movement of the spindle head around the origin in the tool change area, so that the arm main body 161 is slid. Performs a predetermined swinging motion.

Further, on the back side of the magazine base 141, a hook-shaped limiting cover 110 that is in contact with the cam follower 166 and limits the swinging of the arm main body 161 is fixed. A cutout hole (not shown) is provided in a portion of the limiting cover 110 that faces the grip arm 160 that is rotationally indexed. That is, only the cam follower 166 of the grip arm 160 that is indexed in rotation can slide in contact with the cam body through the notch hole. Therefore, only the arm main body 161 of the grip arm 160 indexed for rotation can swing. Further, a stopper 115 is fixed to the front surface of the restriction cover 110 to abut the abutment portion 164 that is the non-free end of the arm body 161 and restrict the swing range of the arm body 161 to a certain range.
Japanese Patent Publication No. 7-80109

  However, in the tool changer described in Patent Document 1 and the conventional tool magazine 140 shown in FIG. 9, the clevis 162 supporting the grip arm 160 is positioned and abutted on the back surface of the magazine base 141, and the positioned clevis 162 is positioned. On the other hand, a screw 180 is attached from the rear of the magazine base. When the grip arm 160 is repaired and replaced, the screw 180 cannot be removed from the front side of the magazine base 141. Therefore, after removing the entire tool magazine 140 from the tool changer, the grip arm 160 has to be pulled out rearward, and there is a problem that repair and replacement of the grip arm 160 is troublesome. Further, if the grip arm 160 is pulled out rearward as it is, the non-free end of the grip arm 160 is caught by the restriction cover 110, so that the restriction cover 100 must be removed, and repair and replacement of the grip arm 160 is further troublesome. There was also a problem.

  The present invention has been made to solve the above-described problem, and an object of the present invention is to provide a machine tool including a tool magazine that can easily replace a grip arm without removing the entire tool magazine.

  In order to achieve the above object, a machine tool according to a first aspect of the present invention includes a head support, a spindle head supported by the head support so as to be reciprocally movable, and movement of the spindle head to the spindle head. A spindle that is rotatably provided so that the rotation axis is parallel to the direction, and a tool holder is detachably mounted at one end; and a tool changer that replaces the tool holder that is mounted on the spindle. The tool changer includes a tool magazine that is rotatably supported by the head support and holds a plurality of the tool holders so that the tool holders can be rotationally indexed. The tool magazine is adjacent to the spindle head. A disk-shaped magazine body that is erected and supported by the head support so as to be rotatable about a single axis, and is radially supported on the outer periphery of the magazine body, and the tool holder A plurality of grip arms to be supported, wherein the grip arm is provided with an arm body, a grip portion provided at one end of the arm body, for gripping the tool holder, and the one end and the other end of the arm body. And a fulcrum stand fixed in contact with the outer peripheral side of the back surface of the magazine main body facing the spindle head. The outer periphery of the magazine main body is connected to the rotation axis of the magazine main body. A hole penetrating in parallel is provided, and the fulcrum base is provided with a screw hole communicating with the hole, and the hole and a screw screwed into the screw hole are attached from the front side of the magazine body. ing.

  In addition to the configuration of the invention according to claim 1, the machine tool of the invention according to claim 2 has a cam surface formed on a front surface of the spindle head facing the magazine body, A cam follower support portion that supports a cam follower that abuts and slides on the cam surface on the spindle head side is provided at a portion that is pivotally supported by the fulcrum base, and the spindle follows the reciprocating movement of the spindle head. The cam follower of the grip arm, which is rotationally indexed to a close proximity position, slides in contact with the cam surface, so that the gripping portion moves away from the proximity position and the main shaft about the fulcrum base. Swing between positions.

  According to a third aspect of the present invention, in addition to the configuration of the first or second aspect of the invention, the machine body according to the third aspect of the invention is configured such that the back side of the magazine main body abuts on the cam follower of the grip arm and the arm main body. A cover member is provided for restricting the swinging of the cam follower, and the cam follower is brought into contact with and slides on the cam surface at a portion of the limiting cover member facing the grip arm that is rotationally indexed to the close position. A notch is provided.

  According to a fourth aspect of the present invention, in addition to the configuration of the third aspect of the invention, the limiting cover member includes a main cover having the notch, and the main body side of the main cover. And is divided into an auxiliary cover that is detachably fixed to the opposite surface and shields a part of the notch, and the auxiliary cover has the arm body through the part of the notch. There is provided a restricting member that abuts against the other end of the arm and restricts the swing range of the arm body.

  In the machine tool according to the first aspect of the present invention, the plurality of grip arms are supported radially on the outer periphery of the magazine body. In this grip arm, a fulcrum base that pivots between one end and the other end of the arm body is fixed in contact with the outer peripheral side of the back surface of the magazine body, so that the arm body swings around the fulcrum base. It comes to move. A hole penetrating in parallel with the rotation axis of the magazine body is provided on the outer periphery of the magazine body, and a screw hole communicating with the hole is provided on the fulcrum stand. Thereby, since the screw which fixes a fulcrum base can be attached from the front side of a magazine main body, even if it does not remove a tool magazine from a tool change apparatus, one grip arm can be removed easily. Therefore, the repair and replacement work for the grip arm can be performed quickly and easily.

  Further, in the machine tool of the invention according to claim 2, in addition to the effect of the invention of claim 1, the cam follower of the grip arm that is rotationally indexed to a close position close to the spindle is based on the reciprocating movement of the spindle head. By sliding in contact with the cam surface, the gripping portion can swing between the proximity position and the retraction position about the fulcrum base. That is, only the grip arm that is rotationally indexed among the plurality of grip arms can be swung.

  Further, in the machine tool of the invention according to claim 3, in addition to the effect of the invention of claim 1 or 2, the cam follower of the grip arm comes into contact with the limiting cover member provided on the back side of the magazine body, so that the arm Although swinging of the main body is restricted, a notch is provided in a portion facing the rotationally indexed grip arm, so that the cam follower abuts on the cam surface and slides through the notch. be able to. Thereby, it is possible to selectively swing only the arm body of the grip arm that is indexed for rotation.

  In the machine tool of the invention according to claim 4, in addition to the effect of the invention of claim 3, when the arm body of the grip arm that is indexed by rotation swings, the other end of the arm body is the auxiliary cover. Abuts on the limiting member provided in the. As a result, the swing range of the arm body can be limited, so that the swing range of the arm body can be adjusted to the minimum necessary. Further, since the auxiliary cover is detachably fixed to the surface of the main cover opposite to the magazine body side, when removing the grip arm from the magazine body, the other end of the arm body is removed by removing the auxiliary cover. Does not come into contact with the restricting member, the grip arm can be pulled out rearward of the magazine body as it is. That is, since it is only necessary to remove the auxiliary cover without removing the entire limiting cover member from the back side of the magazine body, it is possible to quickly and easily repair and replace the grip arm.

  Hereinafter, a machining center 1 according to an embodiment of the present invention will be described with reference to the drawings. 1 is a longitudinal sectional view showing the main part of the machining center 1, FIG. 2 is a front view of the tool magazine 40, and FIG. 3 is a partially enlarged sectional view in the direction of arrows AA shown in FIG. 4 is a partially enlarged cross-sectional view in the direction of arrows BB shown in FIG. 2, FIG. 5 is a perspective view of the grip arm 60, and FIG. 6 is a rear view of the tool magazine 40. 7 is a rear view of the tool magazine 40 (a state where the auxiliary cover 102 is removed), and FIG. 8 is a state where the auxiliary cover 102 is removed from the magazine base 41 shown in FIG. It is a partial expanded sectional view of the state made to do. 1 to 8, for convenience of explanation, the armor cover 78 fixed to the arm body 61 of the grip arm 60 indexed for rotation is omitted.

  In the following description, the X-axis direction indicates the left-right direction of the machining center 1, the Y-axis direction indicates the front-rear direction of the machining center 1, and the Z-axis direction indicates the vertical direction of the machining center 1. . Further, the left side of FIG. 1 is the front of the machining center 1, the right side is the rear, the front side of the paper is the right side, and the depth side of the paper is the left side.

  First, the configuration of the machining center 1 will be schematically described. As shown in FIG. 1, the machining center 1 includes a prismatic column 10 erected vertically at an upper portion behind a base (not shown), and a vertical direction along the front surface (surface on the front side of the base) of the column 10. A spindle head 24 that is movably supported on the spindle, a spindle 30 that is rotatably supported at the tip (lower end) of the spindle head 24, and on which a tool holder (not shown) that holds the tool is mounted, and the spindle head 24 And a tool changer 2 that automatically changes a tool holder mounted on the main shaft 30 to another tool holder. Further, a table (not shown) on which the work can be detachably fixed is installed on the base. Then, by moving the spindle head 24 and the spindle 30 with respect to the work fixed on the table, it is possible to perform processes such as “thread cutting”, “drilling”, and “spot facing”. Hereinafter, various structures and various mechanisms of the machining center 1 will be described in order.

  First, the elevating mechanism of the spindle head 24 will be described. As shown in FIG. 1, a pair of guide rails 14 extending in the vertical direction are supported on the front surface of the column 10, and are rotatably supported inside the pair of guide rails 14, and extend parallel to the guide rails 14. A ball screw 12 is provided. A spindle head 24 is attached to the pair of guide rails 14 through a sliding top 15 so as to be movable up and down. A nut 13 is fixed to the back side of the spindle head 24. A ball screw 12 is screwed into the nut 13 and inserted therethrough. Furthermore, the ball screw 12 is rotationally driven in both forward and reverse directions by a servo motor 11 disposed above the frame 18. Thereby, the nut 13 screwed into the ball screw 12 can be raised or lowered, so that the spindle head 24 can be raised or lowered along the guide rail 14.

  Next, the internal structure of the spindle head 24 will be described. As shown in FIG. 1, a main shaft 30 is rotatably supported inside the front side of the main shaft head 24. The main shaft 30 is coupled to a tool driving motor 22 disposed above the frame 18 via a coupling 23. Therefore, the main shaft 30 is rotationally driven by the motor 22. Furthermore, a tool holding hole 31 in which a tool holder is mounted is provided in the lower part of the main shaft 30. The tool holding hole 31 is a hole into which an arbor (not shown) that is an attachment portion of the tool holder (not shown) is fitted. Here, when the arbor of the tool holder is inserted into the tool holding hole 31, a pull stud (not shown) provided in the holder is provided in the main shaft 30 and clamped (clamped) by the holder clamping member 32. 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 holder holding member 32 holds the pull stud. It is released (unclamped). In this way, the tool holder on the main shaft 30 is removed.

  Next, a tool holder clamping / clamping release mechanism will be described. As shown in FIG. 1, a crank lever 20 having a substantially L shape when viewed from the right side is pivotally supported via a support shaft 21 inside the rear end side 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. And the front-end | tip part of the horizontal lever 20a can be engaged with the pin 35 projected orthogonally to the above-mentioned draw bar 34. As shown in FIG. 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 contact with and separated from the cam follower 17 disposed in the servo motor 11. Further, a tension coil spring (not shown) is elastically interposed between the vertical lever 20b and the spindle head 24. That is, when the crank lever 20 is viewed from the right side, the crank lever 20 is always urged clockwise. Therefore, the pressing on the pin 35 by the horizontal lever 20a is always released.

  Therefore, when the spindle head 24 is raised by driving the servo motor 11, 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. Therefore, since the horizontal lever 20 a is pressed downward while engaging the pin 35, the holder holding member 32 is biased via the draw bar 34. At the same time, the clamp on the pull stud of the tool holder is released. With such a mechanism, the tool holder is clamped / unclamped.

  Next, the structure of the tool changer 2 will be described. As shown in FIGS. 1 and 2, the tool changer 2 includes a tool magazine 40 that supports a plurality of tools. The tool magazine 40 is mainly composed of a cylindrical magazine base 41 with a hook and a plurality of grip arms 60 supported radially on the outer periphery of the magazine base 41. The magazine base 41 is rotatably supported by a magazine support base 37 fixed to the front end portions of the pair of frames 18 and 18. More specifically, a support shaft 45 extending obliquely downward toward the front of the spindle head 24 is fixed to the magazine support base 37, and the magazine base 41 is connected to the support shaft 45 via a plurality of bearings 46. It is pivotally supported.

  Next, the magazine base 41 will be described. As shown in FIG. 3, the magazine base 41 is mainly configured by 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 boss portion 43. ing. The boss portion 43 is fitted with a grip support collar 88 having a guide surface 88a having a circular section in the outer periphery. A steel ball 90 of a contact portion 64 (to be described later) of the grip arm 60 is elastically contacted with the guide surface 88a.

  Further, an indexing disc 47 centered on the support shaft 45 is fixed to the rear end portion of the boss portion 43 via a bolt (not shown). A plurality of roller-shaped cam followers (not shown) are provided on one side surface of the indexing disc 47 corresponding to the position where the grip arm 60 is disposed. On the other hand, an indexing motor 50 is disposed on the upper portion of the casing 52 erected on the magazine support base 37. A part of a rotary indexing mechanism including a plurality of gears and a cam 150 is connected to the rotation shaft of the motor 50, and the cam groove of the cam 150, which is one component of the rotary indexing mechanism, A plurality of cam followers of the indexing disc 47 are sequentially fitted. Thereby, the indexing disc 47 can perform intermittent indexing rotation.

  Further, a restricting cover 100 is fixed to the rear end portion of the boss portion 43 and is formed in a bowl shape and abuts on a cam follower 66 (to be described later) of the grip arm 60 to restrict the swinging motion of the grip arm 60. The restriction cover 100 includes a main cover 101 that has a disk shape when viewed from the front and a rectangular shape that is fixed to cover the cutout hole 101a (see FIG. 7) provided at the lower portion of the main cover 101. This is a two-divided cover composed of a cover 102. As shown in FIG. 7, the cutout hole 101 a is formed in a rectangular shape that is horizontally long when viewed from the front, and is located on the lower side of the main cover 101 and at a portion facing the grip arm 60 that has moved to the index position closest to the main shaft 30. Is provided. Further, the cutout hole 101a is adjusted to a size that exposes the tip of the abutting portion 64 that is the non-free end of the grip arm 60 when the magazine base 41 is viewed from the back side. Fixing holes 101b and 101b for fixing the auxiliary cover 102 to the main cover 101 are provided on the left and right sides of the cutout hole 101a.

  On the other hand, as shown in FIGS. 3 and 6, the auxiliary cover 102 is provided with a notch hole 102a that is opposed to the notch hole 101a of the main cover 101 and is smaller than the notch hole 101a. The cutout hole 102a is formed in a rectangular shape that is vertically long when viewed from the front, and is adjusted to a size that exposes a cam follower 66 (to be described later) of the grip arm 60 when the magazine base 41 is viewed from the back side. Furthermore, fixing holes (not shown) facing the fixing holes 101b and 101b of the main cover 101 are respectively provided on the left and right sides of the cutout hole 102a, and screws 85 and 85 are tightened, respectively. In addition, the front surface of the auxiliary cover 102 (the surface facing the grip arm 60) has an L-shaped cross section that abuts on the tip of a contact portion 64 (to be described later) of the grip arm 60 to limit the swing range of the arm body 61. A stopper 105 (see FIG. 3) is provided.

  When such an auxiliary cover 102 is fixed to the main cover 101, first, the front surface of the auxiliary cover 102 is overlapped with the back surface of the main cover 101 while the stopper 105 is inserted into the notch hole 101a. Next, the fixing hole of the auxiliary cover 102 is opposed to the fixing holes 101b and 101b of the main cover 101, and screws 85 are tightened as shown in FIG. Thereby, the auxiliary cover 102 can be fixed to the main cover 101. Further, the stopper 105 can be positioned and fixed simply by fixing the auxiliary cover 102 to the main cover 101.

  On the other hand, as shown in FIG. 4, in order to fix a clevis 62 (described later) of the grip arm 60 on the outer peripheral side of the collar portion 42, the longitudinal direction of the support shaft 45 extends from the front surface to the rear surface of the collar portion 42. A pair of fixing holes 48, 48 penetrating in parallel with each other are arranged in order in the circumferential direction. Further, on the inner surface of the fixing hole 48, the same screw groove as the screw groove formed on the inner surface of the fixing hole 68 provided in the clevis 62 of the grip arm 60 is formed. That is, the clevis 62 of the grip arm 60 can be fixed to the outer peripheral side of the back surface of the collar portion 42 by the screw 80 screwed into the screw groove of the fixing hole 48. Further, a counterbore hole 49 for embedding the head portion of the screw 80 is provided in an opening at one end portion on the surface side of the flange portion 42 in the fixing hole 48. Thereby, since the head of the screw 80 does not protrude from the surface of the collar portion 42, the grip arm 60 can be replaced safely. Since one grip arm 60 is fixed to the pair of fixing holes 48, 48, when there are 14 grip arms 60 as in the present embodiment, 14 pairs of fixing holes 48, 48 are provided. Are arranged on the outer periphery of the flange 42.

  Next, the structure of the grip arm 60 will be described. As shown in FIG. 3, a plurality of grip arms 60 (14 in the present embodiment) are fixed on the outer peripheral side of the back surface of the collar portion 42 of the magazine base 41 in the circumferential direction at a required central angle. . As shown in FIGS. 4 and 5, the grip arm 60 is pivotally supported via a clevis 62 serving as a fulcrum base for the swinging motion of the grip arm 60 and a pivot shaft 67 provided on the clevis 62. A bent bar-shaped arm main body 61, a Y-shaped gripping portion 63 that grips the tool holder, and a non-free end of the arm main body 61 are provided on the distal end side that is the free end of the arm main body 61. The cylindrical contact portion 64 that houses the compression coil spring 92 and elastically supports the steel ball 90, and the portion that is pivotally supported by the pivot shaft 67 of the arm body 61, can freely rotate the cam follower 66. And a cam follower support portion 65 that supports the main body. Further, as shown in FIGS. 2, 3, and 6, a metal armor cover for preventing the grip arm 60 from being damaged by the collision of chips is formed on the outer surface of the arm body 61 that is bent in a mountain shape. 78 is fixed. Thereby, when the tool magazine 40 is viewed from the front, as shown in FIG. 2, the 14 armor covers 78 are arranged in the circumferential direction at a required central angle on the outer peripheral side of the magazine base 41, The 14 grip arms 60 can be obscured.

  As shown in FIGS. 4 and 5, the clevis 62 is formed in a substantially L-shaped cross section. The clevis 62 extends obliquely from one end of the plate-like fixing portion 62 a and the fixing portion 62 a. It is comprised from the axial support part 62b which has. The fixing portion 62a is provided with a pair of fixing holes 68 that penetrate in the thickness direction of the fixing portion 62a. The pair of fixing holes 68 and 68 correspond to a pair of fixing holes 48 and 48 (see FIG. 4) arranged in the outer periphery of the collar portion 42 of the magazine base 41.

  As shown in FIG. 5, the gripping portion 63 is provided at a non-opening / closing type fork portion 69 for sandwiching a groove portion provided around the outer diameter portion of the tool holder, and an inner end portion of the fork portion 69. And a pair of support pins 73 and 73 which are accommodated so as to be elastically retractable by a compression coil spring (not shown). Further, cam followers 72 are provided on the outer sides of the end portions divided on both sides of the bifurcated portion 69, and the center of the support pin 73 is the center of rotation. In the gripping portion 63, the forked portion 69 is aligned with the groove portion of the tool holder, and the pair of support pins 73, 73 are inserted into and contacted with the groove portion. The support pins 73 and 73 are retracted while pushing back the compression coil spring, whereby the tool holder is gripped by the gripping portion 63.

  As shown in FIG. 4, the cam follower 72 slides in contact with a cam surface of a fixed cam body (not shown) provided at the tip (lower end) of the spindle head 24 shown in FIG. As a result, the bifurcated portion 69 of the grip portion 63 is accurately guided to the groove portion of the tool holder attached to the main shaft 30. On the other hand, the cam follower 66 slides on the cam surface of the movable cam body 28 fixed to the front surface of the spindle head 24 shown in FIG. The movable cam body 28 is pivotally supported by a spindle (not shown) on the front surface of the spindle head 24. Further, since a compression coil spring (not shown) is disposed between the movable cam body 28 and the spindle head 24, the movable cam body 28 is supported in an elastically floating state. Therefore, when the cam follower 66 slides on the cam surface of the movable cam body 28, the arm body 61 swings around the pivot shaft 67, so that the cam follower 72 is attached to the fixed cam body provided at the distal end portion of the spindle head 24. It is designed to be pressed elastically.

  As shown in FIGS. 3 and 4, the abutting portion 64 is formed in a cylindrical shape, and a compression coil spring 92 is attached to the inside dead hole thereof, and the compression coil spring 92 is attached to the compression coil spring 92 via a buffer member 93. The steel ball 90 to be energized is stored. Furthermore, a part of the steel ball 90 protrudes from the opening of the dead hole. The steel ball 90 of the contact portion 64 is elastically in contact with the guide surface 88a of the grip support collar 88 that is externally inserted into the boss portion 43 of the magazine base 41. Further, a notch groove 88b is provided on the magazine base 41 side of the guide surface 88a, and each grip arm 60 in an indexing standby state (a state in which rotation is not indexed) causes the steel ball 90 to pass through the notch groove 88b. To settle down. Thereby, the arm main body 61 can be stably held so that the gripping portion 63 of each grip arm 60 in the indexing standby state is located at the retracted position away from the main shaft 30.

  Next, the fixing structure of the grip arm 60 will be described. As shown in FIG. 4, the clevis 62 of the grip arm 60 is fixed to the outer peripheral side of the back surface of the collar portion 42 of the magazine base 41. A screw 80 that is screwed into the fixing hole 48 of the collar part 42 and the fixing hole 68 of the clevis 62 is attached from the front side of the collar part 42. Therefore, when removing the grip arm 60 from the magazine base 41, a pair of screws 80 and 80 (see FIG. 2) for fixing the clevis 62 of the grip arm 60 to be replaced without removing the entire magazine base 41. If it is removed from the front side of the collar portion 42, only the grip arm 60 can be removed. On the contrary, even when the grip arm 60 is attached to the collar part 42, it is not necessary to remove the entire magazine base 41 and can be attached from the front side of the collar part 42. Thereby, the exchange operation | work of the grip arm 60 can be made quick and easy.

  Next, the swinging operation of the grip arm 60 will be schematically described. When the spindle head 24 shown in FIG. 1 is reciprocated in the Z-axis direction, the cam follower 72 of the grip arm 60 that has been indexed and moved to the position closest to the spindle 30 comes into contact with the cam surface of the fixed cam body. On the other hand, the cam follower 66 contacts the cam surface of the movable cam body 28. When the cam follower 72 and the cam follower 66 slide along the respective cam surfaces, the arm body 61 swings in the front-rear direction of the tool magazine 40 about the pivot shaft 67. At this time, the steel ball 90 of the contact portion 64 of the grip arm 60 is detached from the notch groove 88b of the grip support collar 88 and moves along the arcuate guide surface 88a. On the other hand, the grip arms 60 in the indexing standby state are maintained in their postures without swinging because the steel balls 90 of the respective contact portions 64 settle in the notch grooves 88b of the grip support collar 88. In addition, as shown in FIG. 3, since the limiting cover 100 is disposed behind the cam follower 66 of each grip arm 60 in the index standby state, the swing of each grip arm 60 in the index standby state is performed. Is definitely limited.

  Next, a procedure for replacing the grip arm 60 will be described. First, one grip arm 60 to be exchanged is moved to the rotation index position. Next, in the limiting cover 100 shown in FIG. 6, screws 85 and 85 for fixing the auxiliary cover 102 are removed, and the auxiliary cover 102 is removed from the main cover 101. Then, as shown in FIG. 7, when the tool magazine 40 is viewed from the back side, all of the tip of the contact portion 64 of the grip arm 60 is exposed through the cutout hole 101 a of the main cover 101. Further, as shown in FIG. 8, the stopper 105 is also removed when the auxiliary cover 102 is removed, so that the contact portion 64 can swing through the notch hole 101 a of the main cover 101. That is, the steel ball 90 protruding from the tip of the contact portion 64 can be separated from the guide surface 88 a of the grip support collar 88.

  Further, as shown in FIG. 7, since there is no obstacle behind the grip arm 60, the grip arm 60 can be pulled out as it is. Next, the pair of screws 80, 80 that turn to the front side of the magazine base 41 and fix the clevis 62 of the grip arm 60 to be exchanged shown in FIG. Thereby, since the clevis 62 comes off from the back surface of the collar part 42, the grip arm 60 can be pulled out as it is. Further, when the grip arm 60 is attached, the grip arm 60 can be attached without removing the magazine base 41 by performing an operation reverse to the above-described removal operation. Thus, since it is not necessary to remove the magazine base 41 from the frames 18, 18, the grip arm 60 can be exchanged quickly and easily.

  In the above description, the column 10 shown in FIG. 1 corresponds to the “head support” of the present invention, the clevis 62 shown in FIG. 4 corresponds to the “fulcrum base” of the invention, and the fixing hole shown in FIG. 48 corresponds to the “hole” of the present invention, the fixing hole 68 shown in FIG. 4 corresponds to the “screw hole” of the invention, the screw 80 corresponds to the “screw” of the invention, and the notch shown in FIG. The hole 101a corresponds to the “notch” of the present invention, and the stopper 105 shown in FIG. 3 corresponds to the “restricting member” of the present invention.

  As described above, in the tool magazine 40 of the machining center 1 according to the present embodiment, the clevis 62 that fixes the arm body 61 of the grip arm 60 so as to be swingable is provided on the outer peripheral side of the back surface of the collar portion 42 of the magazine base 41. It is fixed. A screw 80 that is screwed into the fixing hole 48 of the collar part 42 and the fixing hole 68 of the clevis 62 is attached from the front side of the collar part 42. Therefore, when removing the grip arm 60 from the magazine base 41, the pair of screws 80 and 80 for fixing the clevis 62 of the grip arm 60 to be exchanged are attached to the front surface of the collar portion 42 without removing the entire magazine base 41. If it is removed from the side, only the grip arm 60 can be removed. On the contrary, even when the grip arm 60 is attached to the collar part 42, it is not necessary to remove the entire magazine base 41 and can be attached from the front side of the collar part 42. Thereby, the exchange operation | work of the grip arm 60 can be made quick and easy.

  Further, on the back side of the magazine base 41, a restriction cover 100 that is in contact with the cam follower 66 of the grip arm 60 and restricts the swing of the grip arm 60 is fixed. The restriction cover 100 is a two-divided cover including a main cover 101 and an auxiliary cover 102. A notch hole 101a is provided in a portion below the main cover 101 and facing the grip arm 60 at the index position. The notch hole 101a is adjusted to a size that exposes the tip of the contact portion 64 of the grip arm 60 when the magazine base 41 is viewed from the back side. On the other hand, the auxiliary cover 102 is also provided with a notch hole 102a smaller than the notch hole 101a relative to the notch hole 101a of the main cover 101. The notch hole 102a is adjusted to a size that exposes the free end side from the cam follower 66 of the grip arm 60, and a part of the tip of the contact portion 64 is hidden. Further, a stopper 105 is provided on the front surface of the auxiliary cover 102 to abut the tip of the abutting portion 64 of the grip arm 60 and limit the swing range of the arm body 61.

  In such a configuration, when the grip arm 60 is removed, the screws 85 and 85 for fixing the auxiliary cover 102 are removed, and the auxiliary cover 102 is removed from the main cover 101. Then, all of the tip of the contact portion 64 of the grip arm 60 is exposed through the notch hole 101a of the main cover 101. Further, since the stopper 105 is also removed when the auxiliary cover 102 is removed, the contact portion 64 can swing through the cutout hole 101 a of the main cover 101. Therefore, if the steel ball 90 protruding from the tip of the contact portion 64 is detached from the guide surface 88a of the grip support collar 88 and the clevis 62 is removed from the magazine base 41, the grip arm 60 can be pulled out as it is. Thus, since it is not necessary to remove the magazine base 41 from the frames 18, 18, the grip arm 60 can be exchanged quickly and easily.

  Needless to say, the machine tool of the present invention is not limited to the above embodiment, and various modifications are possible. Although the vertical machining center has been described as an example in the above embodiment, the present invention can also be applied to a horizontal machining center.

  In the above embodiment, the number of grip arms 60 supported by the tool magazine 40 is 14, but the number of grip arms 60 is not limited to this.

  Furthermore, the clamping / unclamping mechanism included in the gripping portion 63 of the grip arm 60 is not limited to the mechanism described in the above embodiment, and various modifications can be made.

  The machine tool of the present invention can be applied to a machine tool including a movable member that can move horizontally and vertically.

1 is a longitudinal sectional view showing a main part of a machining center 1. 3 is a front view of a tool magazine 40. FIG. It is a partial expanded sectional view in the AA arrow direction shown in FIG. It is a partial expanded sectional view in the BB arrow direction shown in FIG. 4 is a perspective view of a grip arm 60. FIG. 3 is a rear view of the tool magazine 40. FIG. It is a rear view of the tool magazine 40 (a state where the auxiliary cover 102 is removed). FIG. 4 is a partially enlarged cross-sectional view showing a state in which the auxiliary cover 102 is removed from the magazine base 41 shown in FIG. 3 and the grip arm 60 is further swung. FIG. 6 is a partially enlarged longitudinal sectional view of a conventional tool magazine 140.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Machining center 2 Tool changer 10 Column 24 Spindle head 28 Movable cam body 30 Spindle 40 Tool magazine 41 Magazine base 48 Fixing hole 60 Grip arm 61 Arm main body 62 Clevis 63 Holding part 64 Contact part 65 Cam follower support part 66 Cam follower 68 Fixing hole 80 Screw 100 Limit cover 101 Main cover 101a Notch hole 102 Auxiliary cover 105 Stopper

Claims (4)

A head support, a spindle head supported by the head support so as to be capable of reciprocating, and a spindle head rotatably provided so that a rotation axis thereof is parallel to the movement direction of the spindle head. A machine tool comprising: a spindle on which a tool holder is detachably attached; and a tool changer for exchanging the tool holder attached to the spindle,
The tool changer includes a tool magazine that is rotatably supported by the head support and holds a plurality of the tool holders so that they can be rotated and indexed.
The tool magazine is
A disc-shaped magazine body which is erected adjacent to the spindle head and is supported by the head support so as to be rotatable about a single axis;
A plurality of grip arms that are supported radially on the outer periphery of the magazine body and support the tool holder,
The grip arm is
The arm body,
A grip portion provided at one end of the arm body, for gripping the tool holder;
It comprises a fulcrum stand that pivots between the one end and the other end of the arm body and is fixed in contact with the outer peripheral side of the back surface of the magazine body facing the spindle head.
On the outer periphery of the magazine body, there is provided a hole penetrating in parallel to the rotation axis of the magazine body,
The fulcrum stand is provided with a screw hole communicating with the hole,
The machine tool, wherein the hole and a screw to be screwed into the screw hole are attached from the front side of the magazine body. A cam surface is formed on the front surface of the spindle head facing the magazine body,
A cam follower support portion that supports a cam follower that slides in contact with the cam surface on the spindle head side is provided at a portion of the arm body that is pivotally supported by the fulcrum base.
Based on the reciprocating movement of the spindle head, the cam follower of the grip arm, which is rotationally indexed to a proximity position close to the spindle, slides in contact with the cam surface, so that the gripping part moves the fulcrum base. 2. The machine tool according to claim 1, wherein the machine tool swings between the proximity position and a retracted position spaced apart from the main shaft. On the back side of the magazine body is provided a limiting cover member that abuts on the cam follower of the grip arm and restricts swinging of the arm body,
A portion of the limiting cover member that is opposed to the grip arm that is rotationally indexed to the proximity position is provided with a notch for sliding the cam follower against the cam surface. The machine tool according to claim 1 or 2. The limiting cover member is
A main cover having the notch,
The main cover is detachably fixed to the surface opposite to the magazine body side, and is divided into an auxiliary cover that shields a part of the notch,
The auxiliary cover is provided with a restricting member that contacts the other end of the arm body through the part of the notch and restricts a swing range of the arm body. The machine tool according to claim 3.

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