JP2008055576A - Rotary tool turret - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide high rigidity durable for heavy cutting to a rotary tool driving mechanism and prevent noises or vibrations due to thermal distortion in a tool turret with a driving mechanism of a rotary tool such as an end mill and a milling cutter. <P>SOLUTION: A turret case 1 is indexably and rotatably mounted to a tool post body 2, and an indexing position is fixed by a coupling 23. A guide block 5 is provided in the turret case 1 non-rotatably relative to the tool post body 2 around an indexing shaft, so as to journal a connection shaft 7 arranged in a diameter direction in the turret case 1. The guide block 5 is journalled by the turret case 1 via two bearings 15, 16 at positions near both sides of the connection shaft 7. A base end of a supporting lever 6 extending from the guide block 5 is non-relative-rotatably connected with the tool post body 2 via, for example, a flexion member 61 allowing axial displacement. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a tool turret of a machine tool, and more particularly to a rotary tool turret having a rotary tool drive mechanism such as a milling cutter or an end mill.

  As is well known, the tool turret is for processing a workpiece by selecting a plurality of tools mounted on the outer periphery of the turret by indexing rotation of the turret. The tools attached to the turret include a fixed tool such as a bite and a rotary tool such as a drill. A tool turret (referred to as “rotary tool turret” in this specification) that can be attached to the rotary tool is provided. A tool drive mechanism is provided inside.

  Various types of rotary tool turrets have been proposed. Currently, the only commonly used rotary tool turret is connected to a connecting shaft inside the turret and rotates only at the rotary tool indexed at the machining position. In addition to the fixed tools such as the cutting tool, the rotating tool that is not indexed at the machining position does not rotate.

  FIG. 3 is a diagram showing an example of a conventional structure of this type of rotary tool turret, which is a structure proposed by the applicant of the present application in Patent Document 1. In FIG. In the figure, a turret case 1 provided with tool mounting holes 11 on the outer periphery at predetermined intervals is fixed to the end of a hollow indexing shaft 3 rotatably supported by bearings 21 and 22 on a tool post body 2. . The turret case 1 is provided with an opening 12 in the center of the front face for the purpose of assembling the turret. A perforated disk-shaped bearing housing 13 is fitted into the opening, and a bearing presser lid 14 It is closed.

  The turret case 1 is connected to an indexing motor (not shown) via a gear 31 fixed in the middle of the indexing shaft 3, and an angle corresponding to the arrangement interval of the tool mounting holes 11 provided on the outer periphery of the turret case 1. The turn is indexed in units.

  In the turret case 1, a guide block 5 having a shaft hole in the radial direction of the turret case 1 is fixed to the tip of a hollow support rod 6 inserted through the hollow hole of the indexing shaft 3. . The guide block 5 is integrally formed with a hollow short support shaft 56 whose axial center coincides with the support rod 6 on the tip side, and this support shaft 56 is attached to the inner periphery of the bearing housing 13 with an angular contact. It is supported by a bearing 20.

  The base end portion of the support rod 6 protruding from the indexing shaft 3 is connected to the tool post body 2 by a bending disk 61 having bending elasticity in the direction perpendicular to the surface (indexing axis direction). By this connection, the guide block 5 is fixed in the direction around the indexing shaft 3, and the shaft hole always faces the indexing direction of the tool regardless of the rotation of the turret case 1. The bending disc 61 has high rigidity with respect to deformation in the torsional direction around the axis and displacement of the center, while the minute displacement in the axial direction of the support rod 6 is absorbed by its own bending.

  That is, the guide block 5 is supported at both ends by the bearing 20 and the bending disc 61 at both ends of the distal end portion and the base end of the support rod 6. The bearing 20 is fixed in the axial direction by a bearing retainer lid 14 whose outer ring is bolted to the bearing housing 13 in the axial direction, and the inner ring is fixed to the shaft end of the support shaft 56 by an end plate 57 fixed in the axial direction by a bolt. Has been.

  In the hollow hole of the support rod 6, a drive shaft 8 for driving the rotary tool has a bearing 62 that pivotally supports the base end thereof, and a bearing 63 that pivotally supports a first bevel gear 81 fixed to the tip end thereof. It is pivotally supported. The base end of this drive shaft is connected to a tool motor (not shown) via a synchronous belt 84. The connecting shaft 7 is rotatably supported in the shaft hole of the guide block 5 by a bearing 52 at one end thereof and a bearing 53 that supports a second bevel gear 71 fixed at the other end. The second bevel gear 71 fixed to the connecting shaft 7 meshes with the first bevel gear 81.

  A fitting groove 72 that engages with a fitting protrusion 92 in a direction perpendicular to the axis provided at the base end of the tool shaft 91 of the rotary tool holder 9 indexed at the machining position is provided at the distal end of the connecting shaft 7. .

  When the rotary tool 93 mounted on the rotary tool holder 9 is indexed to the machining position, the tool projection rotates with the fitting shaft 92 by fitting the fitting projection 92 and the fitting groove 72 to rotate the tool motor. Sometimes, the rotary tool 93 rotates. The guide block 5 is provided with a ring-shaped guide 55 that guides the fitting surface of the fitting projection 92 of the tool shaft. The guide 55 guides the side surface of the fitting protrusion 92 so that the fitting protrusion 92 can be inserted into the fitting groove 72 and prevents rotation of the rotary tool at a position other than the processing position. .

  The turret case 1 indexed at a predetermined position is finally positioned by a coupling 23 provided between the back surface of the turret case 1 and the tool post body 2. The coupling 23 is a three-piece surface gear joint having a function of precisely defining the index angle, the axial position, and the position of the rotation center of the turret case 1, and is a ring fixed to the rear surface of the turret case 1. Shaped rotating surface gear 24, a ring-shaped fixed surface gear 25 fixed to the tool rest main body 2, and a fitting formed on the front surface of a piston 27 inserted into a ring-shaped cylinder chamber 26 formed in the tool rest main body. Three surface gears with the desurface gear 28 are provided. When the turret case 1 is indexed with the piston 27 retracted and hydraulic pressure is supplied to the cylinder chamber 26 to advance the piston 27, the fitting / removing surface gear 28 moves forward, and the fixed surface gear 25 and the rotating surface gear 24. At the same time, the rotating surface gear 24 is positioned by the fixed surface gear 25 via the fitting / removing surface gear, and high positional accuracy of the turret case 1 is guaranteed.

  Since the angular contact bearing 20 defines the axial relative position between the support shaft 56 and the bearing housing 13, the axial position of the guide block 5 is coupled via the angular contact bearing 20, the bearing housing 13 and the turret case 1. 23.

When machining a workpiece with a rotary tool, the bearings 62, 63, 52, 53 that support the drive shaft 8 and the connecting shaft 7 serve as heat sources. Further, machining heat is transmitted to the tool post body 2 and the turret case 1 through cutting oil. Therefore, an axial position shift due to thermal deformation occurs between the relatively long support rod 6 and the index shaft 3, and this position shift is absorbed by the deformation of the flexible disk 61. Therefore, even if the support rod 6 is thermally deformed, the axial position of the guide block 5 is defined on the angular contact bearing 20 side, and the heat deformation that occurs between the tool shaft 91 and the connecting shaft 7 occurs. Axis misalignment due to can be reduced.
Japanese Patent Laid-Open No. 2004-25404

  Lathes equipped with high-torque tool motors that can use end mills and milling cutters as rotary tools are also called compound lathes. Planar machining and grooving of workpiece peripheral surfaces, which were conventionally performed using a machining center It has come to be used as a machine tool that performs.

  In view of such circumstances, the present invention makes it possible to use a larger rotary tool and to drive the rotary tool at a higher speed, thereby improving the efficiency and accuracy of machining using the rotary tool. The challenge is to obtain a combined lathe. That is, an object of the present invention is to obtain a composite lathe with higher functions by obtaining a rotary tool turret capable of driving a rotary tool at high torque and high speed.

  In order to make it possible to use a larger rotating tool, it is necessary to increase the support rigidity of the tool so that it can withstand a large cutting reaction force and to prevent the occurrence of vibration due to fluctuations in external force. Further, since the amount of heat generated from the bearing is increased by rotating the tool at a high speed, the displacement generated between the tool connecting shaft 7 and the axis of the rotating tool due to the thermal deformation of the accompanying member can be further reduced. is necessary.

  The invention of claim 1 of the present application includes a hollow indexing shaft 3 rotatably supported on the tool rest main body 2 and a fixed index position fixed to the tip of the indexing shaft 3 so that the predetermined indexing position is indicated. The turret case 1 is positioned by a coupling 23 provided between the turret 2, the hollow support rod 6 inserted through the hollow hole of the indexing shaft 3, and the turret case fixed to the tip of the support rod 6. 1, a guide block 5 in the diametrical direction of the turret case 1 that is pivotally supported by the guide block, and a tool hole that is pivotally supported by the hollow hole of the support rod 6. In the rotary tool turret including a drive shaft 8 for transmitting the rotation of the motor 83, and a bending member 61 for connecting the base end of the support rod 6 and the tool post body 2 with axial displacement, the guide block 5 Are both sides of the portion supporting the tool connecting shaft 7 By providing a rotary tool turret, characterized in that are rotatably supported by bearings 15, 16 provided with a thrust direction positioning function to the turret casing 1, it is obtained by solving the above problems.

  The rotary tool turret of the present invention supports a guide block 5 that supports a connecting shaft 7 that is connected to a rotating tool such as an end mill or a mill cutter mounted on the turret case 1. It is pivotally supported by angular contact bearings and deep groove bearings 15 and 16 mounted on the turret case 1 on both sides of the portion and at a position close to the pivotal support portion of the connecting shaft 7.

  With this structure, when the temperature of the turret case 1 and the guide block 5 rises, the thermal displacement of the tool mounting hole 11 and the thermal displacement of the connecting shaft 7 become substantially equal, and the tool connecting shaft 7 due to the temperature rise of the member It is possible to prevent a deviation from occurring with the tool shaft 91. Further, even when there is a difference in the temperature rise between the turret case 1 and the guide block 5, the difference in thermal deformation is almost equally distributed to the left and right around the axis of the connecting shaft 7, so that the connecting shaft 7 and the tool shaft No error occurs with respect to 91.

  Further, according to the structure of the present invention, since the bearings 15 and 16 are provided in positions near the both sides of the guide block 5 at positions almost symmetrical with respect to the axis of the connecting shaft 7, the support rigidity of the guide block 5 is increased. it can.

  That is, in the conventional structure shown in FIG. 3, the guide block 5 is supported by the nearest angular contact bearing 20 and the flexible disc 61 at the base end of the support rod far from the guide block 5, and the support points on both sides are far away. Since they are separated, the support rigidity of the guide block 5 as obtained with the rotary tool turret of the present invention cannot be obtained. Further, since the axial positional relationship between the turret case 1 and the guide block 5 is defined by the angular contact bearing 20 on one side of the connecting shaft 7, the connecting shaft 7 is subjected to thermal deformation or temperature difference between the two. There was a displacement between the axis of the tool and the axis of the rotary tool.

  According to the present invention, it is possible to provide a rotating tool turret that has higher rigidity and no misalignment due to thermal deformation, and it becomes possible to use a high-torque, high-rotation motor as a tool motor. It has become possible to obtain a composite lathe that is improved 1.5 times the conventional composite lathe.

  FIG. 1 is a view showing an example of a rotary tool turret according to the present invention. The turret case 1 provided with the tool mounting holes 11 on the outer periphery at predetermined intervals is similar to the conventional structure of FIG. 3 in that the hollow indexing shaft 3 rotatably supported by the tool post body 2 by bearings 21 and 22 is supported. It is fixed at the tip. The opening 12 on the front surface of the turret case 1 is closed by a bearing housing 13 and a bearing presser lid 14. The indexing shaft 3 is connected to an indexing motor 33 with a reduction gear via an intermediate gear 32 that meshes with a gear 31 fixed in the middle of the shaft.

  In the turret case 1, a guide block 5 provided with a shaft hole in the diametrical direction of the turret case 1 is a deep groove fitted in a bearing housing 13 fitted in the turret case 1 at a position close to both sides of the shaft hole. The bearing 15 and the deep groove bearing 16 fitted at a position on the connection side with the index shaft 3 of the turret case 1 are pivotally supported. A front end of a support rod 6 is fixed to the guide block 5, and a base end of the support rod 6 is connected to the tool post body 2 via a bending disk 61.

  That is, the guide block 5 is supported by bearings 15 and 16 having a thrust direction positioning function that are disposed at substantially symmetrical positions at short intervals across the shaft hole, and only the direction around the indexing shaft is supported by the support block 5. 6 is regulated by a bending disc 61 at the base end of the base plate 6. With this structure, a high support rigidity of the guide block 5 is obtained, and even when the member is thermally deformed, the axis of the tool connecting shaft 7 supported by the shaft hole and the axis of the rotary tool connected to the shaft center. The positional relationship with the heart is maintained with high accuracy.

  The drive shaft 8 inserted through the hollow hole of the support rod 6 is rotatably supported by a bearing 62 that pivotally supports the base end thereof and a bearing 63 that pivotally supports a first bevel gear 81 fixed to the distal end. The base end thereof is connected to the tool motor 83 via the shaft coupling 82. The shaft hole of the guide block 5 is rotatably supported by a bearing 53 that supports the second bevel gear 71 fixed to the tip of the connecting shaft 7 and a bearing 52 that supports the opposite end. ing.

  A fitting groove 72 that fits the tool shaft of the rotary tool holder is provided at the tip of the connecting shaft 7, and an outer circumferential guide that communicates with both ends of the fitting groove is provided on the outer periphery of the guide block 5. A groove 54 is provided (see FIG. 2). The guide groove 54 defines the direction of the rotary tool at a position other than the machining position, like the guide 55 having the structure shown in FIG. The stop position of the tool motor 83 is controlled so that the fitting groove 72 stops at a position where the fitting groove 72 faces the circumferential direction of the guide block 5, that is, at a position where both ends of the fitting groove 72 communicate with the guide groove 54.

  The indexing position of the turret case 1 is fixed by a coupling 23 made of a three-piece surface gear joint similar to the conventional device, and the indexing angle axial position and the axial center position of the turret case 1 are determined by this cup. It is precisely defined by the ring 23.

Sectional drawing which shows one Example of a rotary tool turret Perspective view of guide block Sectional drawing which shows an example of the rotary tool turret of conventional structure

Explanation of symbols

1 Turret case 2 Turret body 3 Indexing shaft 5 Guide block 6 Support shaft 7 Connecting shaft 8 Drive shaft
15,16 Bearing
33 Indexing motor
71,81 bevel gear
83 Tool motor
91 Tool axis

Claims (1)

A hollow indexing shaft (3) rotatably supported on the tool post body (2) and a fixed index position between the indexing shaft and the predetermined indexing position between the tool post body (2) A turret case (1) that is positioned by a coupling (23) provided on the hollow shaft, a hollow support rod (6) inserted through the hollow hole of the indexing shaft (3), and a tip of the support rod. The guide block (5) located in the turret case (1), the tool connecting shaft (7) in the diametrical direction of the turret case (1) supported by the guide block, and the hollow of the support rod (6) A drive shaft (8) that is pivotally supported by the hole and transmits the rotation of the tool motor (83) to the tool connecting shaft (7), and the base end of the support rod (6) and the tool post body (2) in the axial direction. In the rotary tool turret provided with a bending member (61) that allows and allows displacement,
The guide block (5) is pivotally supported on the turret case (1) by bearings (15, 16) having a thrust direction positioning function on both sides of the portion supporting the tool connecting shaft (7). Rotating tool turret characterized by

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