JP2018167385A - Holding arm and machine tool - Google Patents

Abstract

To provide a holding arm which enables smooth movement, and to provide a machine tool including the holding arm.SOLUTION: A holding arm includes: a support part supporting a shaft; a rotary arm which is rotatably connected with the shaft and holds a tool; and a guide part which guides the rotary arm. The guide part has: a side plate extending in a radial direction of the shaft; a protruding plate protruding from the side plate in the axial direction of the shaft; and an arc guide surface which is formed around an axis of the shaft in the protruding plate. The rotary arm is provided with a guide roller which moves on the guide surface.SELECTED DRAWING: Figure 7

Description

  The present invention relates to a gripping arm for gripping a tool and a machine tool including the same.

  2. Description of the Related Art Conventionally, a machine tool includes a spindle head having a spindle, a plurality of gripping arms that grip a tool, and a tool magazine that transports the gripping arm (see, for example, Patent Document 1). The tool magazine includes a rail and a moving table that moves the rail. The gripping arm includes a support portion connected to the moving base, a pivot provided on the support portion, and an arm portion rotatably connected to the pivot.

  Two guide plates are provided on both sides of the support part. The two guide plates face each other, and grooves are formed on the opposing surfaces. The arm portion is disposed between the two guide plates. The arm portion is provided with two plungers that project toward the two guide plates. The plunger faces the groove. The plunger has a housing recess, and the housing recess houses a holding cylinder that holds the ball and a biasing member. The biasing member biases the holding cylinder and the ball into the groove.

  The spindle head includes a cam, and the arm portion includes a cam follower. The spindle head moves up and down, the cam and the cam follower come into contact with each other, and the arm portion rotates around the pivot axis. The plunger ball moves along the groove and guides the arm portion.

JP 2013-176830 A

  When the ball moves in the groove, the holding cylinder may be inclined and contact the inner peripheral surface of the housing recess. At this time, the movement of the holding cylinder and the ball is hindered, and the arm portion may not move smoothly.

  The present invention has been made in view of such circumstances, and an object thereof is to provide a gripping arm capable of smooth movement and a machine tool including the gripping arm.

  The gripping arm according to the present invention is a gripping arm comprising: a support portion that supports a pivot; a rotary arm that is rotatably connected to the pivot and grips a tool; and a guide that guides the rotary arm. The portion includes a side plate extending in the radial direction of the pivot, a protruding plate protruding from the side plate in the axial direction of the pivot, and an arcuate guide surface formed around the axis of the pivot by the protruding plate. And a guide roller for moving the guide surface is provided on the rotary arm.

  In the present invention, a protruding plate is provided on the side plate, a guide surface is formed on the protruding plate, and a guide roller for moving the guide surface is provided on the rotary arm. There are no members that obstruct the movement of the guide roller around the guide roller, and the guide roller moves smoothly.

  The grip arm according to the present invention includes a first urging member that urges the guide roller toward the guide surface.

  In the present invention, the guide roller reliably contacts the guide surface by the biasing force of the first biasing member.

  The grip arm according to the present invention includes a lever that can rotate about an axis parallel to the pivot, and one end of the lever is rotatably connected to the rotary arm, and the guide is connected to the other end of the lever. A roller is provided, and the first biasing member biases the other end of the lever toward the guide surface.

  In the present invention, the lever and the first urging member realize reliable contact with the guide surface of the guide roller, thereby realizing smooth movement of the rotary arm.

  The gripping arm according to the present invention is characterized in that an engaging portion for engaging the guide roller is formed on the guide surface.

  In the present invention, when the gripping arm grips the tool, the guide roller engages with the engaging portion. As a result, the guide roller stops and the tool is positioned relative to the main shaft.

  The gripping arm according to the present invention is provided with two gripping pin units for gripping a tool at the tip of the rotating arm, and the gripping pin unit includes a rotating rod that can rotate around a midway part, A gripping pin provided at one end of the rotating rod and a second biasing member provided at the other end of the rotating rod and biasing the gripping pin toward the tool. .

  In the present invention, by providing a gripping pin at one end of the rotating rod, when the gripping pin comes into contact with the tool, the dimension between the one end of the two rotating rods increases, and the two gripping pins smooth the tool. Grip to. Further, the grip pin securely grips the tool by the second biasing member provided at the other end of the rotating rod.

  The grip arm according to the present invention includes a third urging member that positions the rotary arm in the axial direction of the pivot.

  In the present invention, the rotary arm is positioned in the axial direction of the pivot by the third urging member, and the rotary arm is positioned with respect to the tool.

  A machine tool according to the present invention includes a spindle on which a tool is mounted and the above-described gripping arm.

  In the present invention, the above-described gripping arm is used for the machine tool, and smooth movement of the guide roller is realized.

  In the gripping arm and the machine tool according to the present invention, a protruding plate is provided on the side plate, a guide surface is formed on the protruding plate, and a guide roller for moving the guide surface is provided on the rotating arm. There are no members that obstruct the movement of the guide roller around the guide roller, and the guide roller moves smoothly. Therefore, smooth movement of the gripping arm can be realized.

It is a perspective view of a machine tool. It is a perspective view of the machine tool which abbreviate | omitted the cover etc. which cover a tool change device and a track. It is a fragmentary sectional view which shows a spindle head schematically. FIG. 6 is a perspective view schematically showing a gripping arm in a gripping posture. FIG. 6 is an exploded perspective view schematically showing a gripping arm in a gripping posture. FIG. 6 is a front view schematically showing a gripping arm in a gripping posture. FIG. 7 is a schematic cross-sectional view taken along line VII-VII shown in FIG. 6. FIG. 6 is a bottom view schematically showing a gripping arm in a gripping posture. It is a left view which shows the guide part schematically. It is a schematic sectional drawing of the holding | grip arm of a non-holding attitude | position. It is the figure which compared the grip arm which uses a roller, and the grip arm concerning an embodiment. It is a perspective view which briefly shows the guide part which concerns on the example of a change. It is a longitudinal cross-sectional view which shows schematically the holding arm which concerns on the example of a change.

  Hereinafter, the present invention will be described in detail with reference to the drawings showing a machine tool according to an embodiment. In the following description, up and down, left and right, and front and rear indicated by arrows in the figure are used. The operator operates the machine tool in front and attaches / detaches the workpiece. FIG. 1 is a perspective view of a machine tool, and FIG. 2 is a perspective view in which a tool changer and a cover for covering a track are omitted.

  The machine tool 100 includes a base 20, a Y-direction moving device 22, an X-direction moving device 26, a vertical pole 28, a Z-direction moving device 30, a spindle head 32, a tool changer 10 and the like. The X direction corresponds to the left-right direction, and the Y direction corresponds to the front-rear direction. The base 20 is fixed on the floor surface. The base 20 supports the upright column 28 so as to be movable in the front-rear direction and the left-right direction via the Y-direction moving device 22 and the X-direction moving device 26. The base 20 supports the work holding device 120. A Z-direction moving device 30 is provided on the upright 28. The Z-direction moving device 30 moves the spindle head 32 in the vertical direction. The tool changer 10 changes a tool attached to the spindle head 32. A cam portion 80 is provided at the front portion of the spindle head 32. The cam portion 80 is composed of a plurality of cam bodies.

  The Y-direction moving device 22 includes two tracks 22a parallel to each other, a plurality of moving bodies 22b, a Y-direction moving base 22c, and a Y-direction drive motor (not shown). The track 22 a extends in the front-rear direction on the upper surface of the base 20. The moving body 22b is fitted to each of the two tracks 22a so as to be movable in the front-rear direction. The Y-direction moving table 22c is fixed on the moving body 22b across the two tracks 22a. The Y-direction moving base 22c moves in the front-rear direction by driving the Y-direction drive motor.

  The X-direction moving device 26 includes two tracks 26a that are parallel to each other, a plurality of moving bodies 26b, an upright column base 26c, and an X-direction drive motor (not shown). The track 26a extends in the left-right direction on the upper surface of the Y-direction moving table 22c. The moving body 26b is fitted to each of the two tracks 26a so as to be movable in the left-right direction. The upright column base 26c is fixed on the moving body 26b across the two tracks 26a. The upright column 28 is fixed on the upright column base 26c. The upright column base 26c moves in the left-right direction by driving the X-direction drive motor. The upright 28 is moved in the front-rear direction and the left-right direction by the Y-direction moving device 22 and the X-direction moving device 26.

  The Z-direction moving device 30 includes two tracks 30a parallel to each other, a plurality of moving bodies 30b, a spindle head base 30c, and a Z-direction drive motor (not shown). The track 30a extends in the vertical direction on the front surface of the upright column 28. The plurality of moving bodies 30b are fitted to the two tracks 30a so as to be movable in the vertical direction. The spindle head base 30c is fixed to the front surface of the moving body 30b across the two tracks 30a. The spindle head base 30c moves in the vertical direction by driving the Z-direction drive motor.

  The spindle head 32 is fixed to the spindle head base 30c. By driving and controlling the X direction drive motor, the Y direction drive motor, and the Z direction drive motor, the spindle head 32 moves back and forth, left and right, and up and down.

  FIG. 3 is a partial sectional view schematically showing the spindle head 32. As shown in FIG. 3, the spindle head 32 rotatably holds a spindle 34 extending in the vertical direction inside the front side. The main shaft 34 has a hollow cylindrical shape. A tapered hole 34a whose inner diameter increases downward is formed in the lower end portion of the main shaft 34. The lower end portion of the main shaft 34 detachably holds the cylindrical tool holder 11 on which a tool is mounted. The tapered mounting portion 12 formed on the upper portion of the tool holder 11 is fitted into the tapered hole 34a.

  In the main shaft 34, a draw bar (not shown) is inserted above the tapered hole 34 a so as to be movable in the axial direction of the main shaft 34. A clamp spring (not shown) is disposed around the draw bar. The clamp spring biases the draw bar upward. The draw bar holds the taper mounting portion 12. When the draw bar is pushed downward against the elastic force of the clamp spring, the draw bar releases the taper mounting portion 12 and the tool holder 11 is detached from the main shaft 34.

  A spindle motor 35 is provided at the upper end of the spindle head 32. The main shaft 34 is connected to a main shaft motor 35. The spindle 34 rotates around the axis by driving the spindle motor 35. The spindle 34 on which the tool holder 11 is mounted rotates to process the workpiece held on the workpiece holding device 120.

  The tool changer 10 includes an oval track (not shown) and a plurality of moving platforms (not shown) that move along the track. The track surrounds the spindle head 32 and the upright column 28, extends from the lower front side to the rear upper side, and is inclined by approximately 30 degrees from the horizontal plane. The plurality of moving platforms are connected in a chain by links. As shown in FIG. 1, a gear 51 and a drive motor 52 are arranged inside the track. The gear 51 is connected to the drive motor 52 and is rotated by the drive of the drive motor 52. The plurality of moving platforms mesh with the gear 51 and rotate on the track by driving of the drive motor 52. Each moving table supports the gripping arm 70.

  As the spindle 34 with the tool holder 11 attached rises, the gripping arm 70 removes the tool holder 11 from the spindle 34 and grips it. A gripping arm 70 that grips the tool holder 11 is disposed at the front end of the track of the tool changer 10, and the spindle 34 that does not grip the tool holder 11 is lowered, so that the spindle 34 mounts the tool holder 11.

  4 is a perspective view schematically showing a gripping arm 70 gripping the tool holder 11, FIG. 5 is an exploded perspective view schematically showing the gripping arm 70 gripping the tool holder 11, and FIG. 6 is a tool holder. 7 is a front view schematically showing the gripping arm 70 in a gripping posture holding the tool 11, FIG. 7 is a schematic sectional view taken along the line VII-VII shown in FIG. 6, and FIG. 8 is a gripping posture in which the tool holder 11 is gripped. 9 is a bottom view schematically showing the gripping arm 70, and FIG. 4 to 9, the gripping arm 70 is arranged at the front end of the track of the tool changer 10 and uses front, rear, upper, lower, left and right.

  The gripping arm 70 includes a support portion 71 that is fixed to the moving table. The support portion 71 extends in the vertical direction and has a plate shape inclined forward. An attachment plate 71f attached to the moving table is provided at the upper end of the support portion 71. Two screw holes 71a are arranged vertically on the right side surface and the left side surface of the support portion 71, and two positioning projections 71b are arranged vertically between the two screw holes 71a. The lower end portion of the support portion 71 supports the pivot shaft 72. The pivot 72 extends to the left and right.

  A pivot arm 73 is provided on the pivot shaft 72. The rotary arm 73 extends vertically and has a plate shape inclined forward. An upper end portion of the rotating arm 73 is rotatably connected to the pivot 72. The left and right end portions of the pivot 72 protrude from the upper end portion of the rotary arm 73, respectively. Flange 73e, 73d is provided in each of the left and right side surfaces of the upper end of the rotary arm 73. The flanges 73e and 73d are arranged around the left and right ends of the pivot 72, respectively. As shown in FIG. 7, a disk-shaped receiving portion 73f is provided below the right flange 73d.

  A first cam follower 73a that abuts against one cam body formed by the cam portion 80 protrudes obliquely rearward and upward from the upper end portion of the rotating arm 73. The first cam follower 73a includes a roller having a left and right direction as a rotation axis direction at a protruding end portion thereof. A second cam follower 73 b that abuts against another cam body constituting the cam portion 80 is provided in the middle of the rotating arm 73. The second cam follower 73b is provided on the rear side of the rotary arm 73, and includes a roller whose left-right direction is the rotation axis direction. An insertion hole 73 c is provided on the right side surface of the rotary arm 73 below the second cam follower 73 b.

  As shown in FIG. 8, a partition plate 73 p extending in the front-rear direction is provided on the lower rear surface of the rotary arm 73. The partition plate 73p is disposed at the center in the left-right direction of the rotary arm 73. Receiving portions 73q and 73r for receiving urging members 75f and 76f described later are provided on the left and right surfaces of the partition plate 73p, respectively. The left-side receiving portion 73q has a disk shape and protrudes to the left. The receiving portion 73r on the right side has a disk shape and protrudes to the right side.

  A U-shaped unit support portion 74 having both ends extending rearward is provided at the lower end portion of the rotating arm 73. Both end portions of the unit support portion 74 are arranged side by side. An insertion groove 74 a extending in the front-rear direction is formed on the left side surface of the unit support portion 74. A through-hole 74b penetrating vertically is provided on each of the upper and lower sides of the insertion groove 74a. The two through holes 74b are arranged coaxially.

  The insertion groove 74 a supports the grip pin unit 75. The grip pin unit 75 includes a rotating rod 75a, a grip pin 75c, a receiving portion 75d, and a biasing member 75f (second biasing member). The rotating rod 75a extends in the front-rear direction, and a through-hole 75b penetrating vertically is formed in the central portion thereof. A grip pin 75c that protrudes to the right is provided at the rear end of the rotary rod 75a. The grip pin 75c rotates with the left-right direction as the rotation axis direction. A receiving portion 75d for receiving a biasing member 75f is provided at the front end of the rotating rod 75a. The receiving portion 75d has a disk shape and protrudes to the right side.

  The rotating rod 75a is inserted into the insertion groove 74a, and the through hole 75b of the rotating rod 75a and the two through holes 74b of the insertion groove 74a are arranged coaxially. A shaft 75e is inserted into each of the through holes 74b and 75b. The rotating rod 75a can rotate around a shaft 75e. A biasing member 75f is held between the receiving portion 75d of the rotating rod 75a and the receiving portion 73q on the left surface. The biasing member 75f biases the front end portion of the rotating rod 75a to the left side.

  An insertion groove 74 c extending in the front-rear direction is formed on the right side surface of the unit support portion 74. A through-hole 74d penetrating vertically is provided on each of the upper and lower sides of the insertion groove 74c. The two through holes 74d are arranged coaxially.

  The insertion groove 74 c supports the grip pin unit 76. The gripping pin unit 76 includes a rotating rod 76a, a gripping pin 76c, a receiving portion 76d, and a biasing member 76f (second biasing member). The rotary rod 76a extends in the front-rear direction, and a through hole 76b penetrating vertically is formed at the center thereof. A grip pin 76c that protrudes to the left is provided at the rear end of the rotary rod 76a. The grip pin 76c rotates with the left-right direction as the rotation axis direction. A receiving portion 76d that receives a biasing member 76f is provided at the front end of the rotating rod 76a. The receiving portion 76d has a disk shape and protrudes to the left. The rotating rod 76a is inserted into the insertion groove 74c, and the through hole 76b of the rotating rod 76a and the two through holes 74d of the insertion groove 74c are arranged coaxially. A shaft 76e is inserted into each of the through holes 74d and 76b. The rotary rod 76a can rotate around a shaft 76e.

  The urging member 76f is held between the receiving portion 76d of the rotating rod 76a and the receiving portion 73r on the right side of the partition plate 73p. The urging member 76f urges the front end portion of the rotating rod 76a to the right side.

  An end plate 77 is disposed on the left side of the pivot 72. An insertion hole 77 a penetrating in the left-right direction is provided in the rear portion of the end plate 77. The diameter of the insertion hole 77a is larger than the diameter of the pivot 72. The left end portion of the pivot 72 is inserted into the insertion hole 77a. At the front end of the end plate 77, two through holes 77b penetrating in the left-right direction are arranged vertically, and two positioning holes 77c are arranged vertically between the two through holes 77b. The two through holes 77 b are arranged at positions corresponding to two screw holes (not shown) on the left side surface of the support portion 71. The two positioning holes 77 c are arranged at positions corresponding to two positioning protrusions (not shown) on the left side surface of the support portion 71.

  The positioning protrusion is inserted into the positioning hole 77c, and the end plate 77 and the support portion 71 are positioned. The through hole 77b and the screw hole are arranged coaxially. A screw 90 is inserted into the through-hole 77b from the left side and connected to the screw hole to fix the end plate 77 to the support portion 71. An urging member 77 f (third urging member) is provided between the peripheral portion of the insertion hole 77 a of the end plate 77 and the left flange 73 e of the rotary arm 73. The urging member 77 f is arranged around the left end portion of the pivot 72. The urging member 77f urges the rotating arm 73 to the right side.

  A guide portion 78 is disposed on the right side of the pivot shaft 72. The guide part 78 includes a side plate 78a extending in the front-rear and up-down directions. The side plate 78a has a rectangular shape in side view. An insertion hole 78m penetrating in the left-right direction is provided at a corner where the upper edge and the rear edge of the side plate 78a meet. The diameter of the insertion hole 78m is larger than the diameter of the pivot 72. The right end portion of the pivot 72 is inserted into the insertion hole 78m.

  A projecting body 78g projecting upward is provided at a corner where the upper edge and the front edge of the side plate 78a meet. A through hole 78h penetrating in the left-right direction is provided in each of the upper end portion and the lower end portion of the projecting body 78g. Two positioning holes 78k are vertically arranged between two through holes 78h in the projecting body 78g. A protruding plate 78b protruding leftward is provided at the lower edge of the left surface of the side plate 78a. A protrusion 78c protruding upward is provided on the left edge of the protrusion plate 78b. A guide surface 78d having an arc shape in side view is formed on the upper surface of the protrusion 78c. The guide surface 78d is formed around the axis of the insertion hole 78m, in other words, around the axis of the pivot 72. A concave portion 78e (engagement portion) is formed at the rear end portion of the guide surface 78d.

  The positioning protrusion 71b is inserted into the positioning hole 78k, and the guide portion 78 and the support portion 71 are positioned. The through hole 78h and the screw hole 71a are coaxially arranged. The screw 91 is inserted into the through-hole 78 h from the right side and connected to the screw hole 71 a to fix the guide portion 78 to the support portion 71. An urging member 78f (third urging member) is provided between a peripheral portion of the insertion hole 78m of the guide portion 78 and the right flange 73d of the rotary arm 73. The biasing member 78 f is disposed around the right end portion of the pivot 72. The urging member 78f urges the rotating arm 73 to the left side.

  A lever 79 is provided on the right side surface of the rotating arm 73. The lever 79 extends back and forth, and the front end portion of the lever 79 is disposed above the rear end portion. A through hole 79 a penetrating left and right is formed at the rear end of the lever 79. The first plate 79b protrudes rightward from the front end of the lever 79. A disc-shaped receiving portion 79c is provided on the upper surface of the first plate 79b. The second plate 79d protrudes downward from the protruding end of the first plate 79b. A guide roller 79e is rotatably supported between the second plate 79d and the lever 79 front end. The guide roller 79e rotates with the left-right direction as the rotation axis direction.

  A shaft 79 f is inserted into the through hole 79 a of the lever 79 and the insertion hole 73 c of the rotating arm 73. The lever 79 rotates around the shaft 79f. The guide roller 79e is disposed on the guide surface 78d. The second plate 79d is disposed between the protrusion 78c and the side plate 78a. A biasing member 79g (first biasing member) is provided between a receiving portion 73f provided on the lower side of the flange 73d and a receiving portion 79c provided on the lever 79. The urging member 79g urges the front end portion of the lever 79 and the guide roller 79e toward the guide surface 78d. In addition, a spring, rubber | gum, etc. are mentioned as each urging | biasing member 75f, 76f, 77f, 78f, 79g mentioned above.

  FIG. 10 is a schematic cross-sectional view of the gripping arm 70 in the non-gripping posture. As shown in FIG. 10, when the tool holder 11 is not gripped, the rotating arm 73 of the grip arm 70 is located on the lower side compared to the case where the tool holder 11 is gripped (see FIG. 7). 79e is located at the front end of the guide surface 78d.

  When the empty gripping arm 70 is disposed at the front end of the track of the tool changer 10, the tapered hole 34a is disposed below the gripping arm 70, and the spindle head 32 to which the tool holder 11 is mounted rises, the first cam follower 73 a and the second cam follower 73 b abut on each cam body constituting the cam portion 80. As shown by the arrow in FIG. 7, the rotary arm 73 rotates upward about the pivot 72, and the grip pins 75 c and 76 c approach the tool holder 11. The tool holder 11 is inserted between the two grip pins 75c and 76c. A groove 11a is formed on the outer peripheral surface of the tool holder 11, and the grip pins 75c and 76c engage with the groove 11a. The guide roller 79e engages with the recess 78e, the rotation of the rotary arm 73 stops, and the rotary arm 73 is positioned.

  When the grip pins 75c and 76c come into contact with the groove 11a, the two rotating rods 75a and 76a rotate against the urging force of the urging members 75f and 76f by the force applied from the groove 11a. The rear ends of 75a and 76a move away from the tool holder 11. The dimension between the rear end portions of the two rotary rods 75a and 76a becomes large, and the grip pins 75c and 76c rotate around their axes, so that the grip pins 75c and 76c smoothly engage with the groove 11a. The spindle head 32 is further raised, and the gripping arm 70 removes and grips the tool holder 11 from the tapered hole 34a. The gripping pins 75c and 76c securely grip the tool holder 11 by the biasing force of the biasing members 75f and 76f.

  As shown in FIG. 7, when the gripping arm 70 is gripping the tool holder 11, the guide roller 79 e is engaged with the recess 78 e and positions the rotating arm 73. When the gripping arm 70 that grips the tool holder 11 is disposed at the front end portion of the track of the tool changer 10 and the tapered hole 34a in which the tool holder 11 is not mounted is disposed above the gripping arm 70, the tool holder 11 and the taper are tapered. The position of the tool holder 11 is aligned with the hole 34a, and the tool holder 11 is disposed directly below the tapered hole 34a.

  When the spindle head 32 is lowered, the tool holder 11 is inserted into the tapered hole 34 a, and the first cam follower 73 a and the second cam follower 73 b abut on each cam body constituting the cam portion 80. As shown by the arrow in FIG. 10, the rotary arm 73 rotates downward about the pivot 72, the grip pins 75 c and 76 c release the tool holder 11, and the grip arm 70 moves away from the main shaft 34.

  When the rotating arm 73 rotates downward, the two rotating rods 75a and 76a rotate against the urging force of the urging members 75f and 76f by the force acting on the grip pins 75c and 76c from the tool holder 11. The rear ends of the two rotary rods 75a and 76a move away from the tool holder 11. The dimension between the rear end portions of the two rotary rods 75a and 76a is increased, and the grip pins 75c and 76c rotate around the axis thereof, so that the grip pins 75c and 76c smoothly release the tool holder 11. The spindle 34 is mounted with the tool holder 11.

  In the embodiment, a protruding plate 78b is provided on the side plate 78a, a guide surface 78d is formed on the protruding plate 78b, and a guide roller 79e for moving the guide surface 78d is provided on the rotary arm 73. There are no members that obstruct the movement of the guide roller 79e around the guide roller 79e, and the guide roller 79e moves smoothly. Therefore, smooth movement of the gripping arm can be realized.

  In addition, the lever 79 and the biasing member 79g realize a reliable contact of the guide roller 79e with the guide surface 78d, thereby realizing a smooth movement of the rotary arm 73. When the rotary arm 73 holds the tool holder 11, the guide roller 79e engages with the recess 78e. As a result, the guide roller 79e stops, and the tool holder 11 is positioned with respect to the tapered hole 34a of the main shaft 34.

  Further, by providing the grip pins 75c and 76c at the rear end portions of the rotary rods 75a and 76a, when the grip pins 75c and 76c come into contact with the tool holder 11, the dimension between the rear end portions of the two rotary rods 75a and 76a. The two holding pins 75c and 76c smoothly hold the tool holder 11. Further, the gripping pins 75c and 76c securely grip the tool holder 11 by the urging members 75f and 76f provided at the front ends of the rotating rods 75a and 76a.

  Further, the rotary arm 73 is positioned in the axial direction of the pivot 72 by biasing members 77f and 78f provided between the end plate 77 and the flange 73e and between the side plate 78a and the flange 73d. Therefore, positioning of the rotary arm 73 with respect to the tool holder 11 can be realized with high accuracy.

  FIG. 11 is a diagram comparing the gripping arm using the roller and the gripping arm according to the embodiment. FIG. 11A shows a grip arm and tool holder 11 using a roller, and FIG. 11B shows a grip arm and tool holder 11 according to the embodiment. In FIG. 11B, description of the grip pin 75c is omitted.

  As shown in FIG. 11A, in place of the grip pins 75c and 76c, when a roller is provided at the rear end portion of the rotating rods 75a and 76a, the roller when the angle of the rotating arm 73 with respect to the tool holder 11 is a predetermined angle or more Cannot engage with the groove 11a. On the other hand, as shown in FIG. 11B, when the holding pins 75c and 76c are used, the holding pins 75c and 76c can be engaged with the groove 11a regardless of the angle of the rotary arm 73 with respect to the tool holder 11.

  Instead of the lever 79, a plunger having a guide roller at the tip may be used. The plunger is directly attached to the rotating arm 73. The plunger has an urging member, and the urging member urges the guide roller toward the guide surface 78d.

(Example of change)
FIG. 12 is a perspective view schematically showing a guide portion 78A according to the modified example, and FIG. 13 is a longitudinal sectional view schematically showing the gripping arm 70A according to the modified example. A recess 73 </ b> G is provided on the lower surface of the rotary arm 73. The recess 73G is disposed between the pivot 72 and the second cam follower 73b. A plate portion 79 </ b> B is provided at the front end portion of the lever 79. A biasing member 79g is provided between the plate portion 79B and the recess 73G. The upper end portion of the biasing member 79g is fitted into the recess 73G.

  The guide portion 78A includes the protruding plate 78b and the protrusion 78c. A guide surface 78D is formed on the upper surface of the protrusion 78c. A groove 78r is formed between the protrusion 78c of the protruding plate 78b and the side plate 78a. Two through holes 78E are provided in the groove 78r. The two through holes 78E are separated in the front-rear direction. The urging member 79g urges the guide roller 79e toward the guide surface 78D. A protrusion 78p protruding leftward is provided at the rear end of the side plate 78a.

  As the rotary arm 73 rotates, the guide roller 79e moves on the guide surface 78D. When the rotary arm 73 rotates rearward and the protrusion 78p contacts the plate portion 79B, the guide roller 79e engages with the rear end portion 78q (engagement portion) of the guide surface 78D. The rear end portion 78q is chamfered. The rotation arm 73 stops at a predetermined position by the contact of the projection 78p with the plate portion 79B and the engagement with the rear end portion 78q of the projection 78c.

  By fitting the urging member 79g into the recess 73G, it is possible to promote downsizing of the gripping arm 70A as compared with the case where the rotation arm 73 is provided with a projection and the urging member 79g is locked to the projection. it can. By providing the through hole 78E in the guide surface 78D, the workpiece chips pass through the through hole 78E and do not accumulate in the groove 78r. In addition, although the recessed part 73G is arrange | positioned between the pivot 72 and the 2nd cam follower 73b, what is necessary is just to arrange | position to the unit support part 74 side rather than the pivot 72.

  It should be thought that embodiment disclosed this time is an illustration and restrictive at no points. The technical features described in each embodiment can be combined with each other, and the scope of the present invention is intended to include all modifications within the scope of claims and the scope equivalent to the scope of claims. Is done.

34 Main shaft 70 Grip arm 71 Support portion 72 Pivot 73 Rotating arm 75, 76 Grip pin unit 75a, 76a Rotation rod 75c, 76c Grip pin 75f, 76f Biasing member (second biasing member)
77f, 78f urging member (third urging member)
78 Guide part 78a Side plate 78b Projection plate 78d, 78D Guide surface 78e Recess (engagement part)
78q Rear end (engagement part)
79 Lever 79e Guide roller 79g Biasing member (first biasing member)
100 machine tools

Claims (7)

In a gripping arm comprising: a support portion that supports the pivot shaft; a rotation arm that is rotatably connected to the pivot shaft and grips the tool; and a guide portion that guides the rotation arm.
The guide part is
A side plate extending in the radial direction of the pivot;
A protruding plate protruding in the axial direction of the pivot from the side plate;
The projecting plate has an arcuate guide surface formed around the axis of the pivot,
A gripping arm, wherein a guide roller for moving the guide surface is provided on the rotating arm. The grip arm according to claim 1, further comprising a first biasing member that biases the guide roller toward the guide surface. Comprising a lever rotatable around an axis parallel to the pivot axis;
One end of the lever is rotatably connected to the rotating arm,
The guide roller is provided at the other end of the lever;
The grip arm according to claim 2, wherein the first biasing member biases the other end portion of the lever toward the guide surface. The gripping arm according to any one of claims 1 to 3, wherein an engaging portion with which the guide roller engages is formed on the guide surface. Two gripping pin units for gripping a tool are provided at the tip of the rotating arm,
The grip pin unit is
A rotating rod that can rotate around the midway part, and
A grip pin provided at one end of the rotating rod;
The second urging member, which is provided at the other end of the rotating rod and urges the grip pin toward the tool, is provided. Gripping arm. The gripping arm according to any one of claims 1 to 5, further comprising a third biasing member that positions the rotary arm in an axial direction of the pivot. A spindle for mounting the tool,
A machine tool comprising the gripping arm according to any one of claims 1 to 6.

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