JP2010240817A - Holder and sleeve for boring cutting tool - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a holder and a sleeve for boring cutting tool enhancing stability in fixation of the boring cutting tool on the holder, improving precision in machining by using the boring cutting tool, achieving stable machining by preventing the occurrence of chattering, and improving interchangeability for mounting a plurality of boring cutting tools different in sizes on one holder for boring cutting tool. <P>SOLUTION: The boring cutting tool inserted into the sleeve having a slit and a groove is fixed by inserting the sleeve into the holder for boring cutting tool and pressing the sleeve from above and below to contract inside diameter of a central hole of the sleeve by using four clamp screws assembled above and below a tip part of the holder. An inner face of the central hole of the sleeve adheres closely to a wide region of the outer periphery of a shank part of the boring cutting tool to increase holding power. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a holder for mounting a boring tool used for inner diameter processing to a tool rest of a machine tool.

  As an example of a holder for mounting a boring tool used for inner diameter machining to a tool post of a machine tool, a boring tool shank portion has been conventionally inserted into the center hole of the holder, and the shank flattening portion is one or two pieces. A structure that is fastened and fixed with a clamp screw is known. A holder for fixing a boring bar with a slit is disclosed in Patent Document 1 below.

  The holder for a boring tool disclosed in Patent Document 1 is provided with a slit that vertically divides the region from the center hole of the holder to the outer peripheral surface from the tip of the holder to the middle of the length, and tightens the slit forming portion to The boring bar is fixed by shrinking the inner diameter.

Similar boring tool holders are also described in the following patent documents.
JP2008-12595 5-44403

  In the conventional holder for a boring bar, the boring bar is fixed by a method of tightening the boring bar in one direction with one or two clamp screws incorporated in the holder. With this method, the boring bar can be fixed only from one direction, and the shank flattened part is tightened with a point screw with a clamp screw. The distance of the cutting tool at the end of the boring bar is increased, the fixing of the cutting tool is insufficient, the clamp rigidity is lowered, chattering occurs during machining, and the boring bar protruding length is limited, making it unsuitable for deep hole machining. In addition, a holder of the same size is required for the boring bar, and a boring bar of a different size cannot be attached.

  In the holder for a boring tool disclosed in Patent Document 1, since the boring tool is fixed by attaching a slit to the holder and shrinking the inner diameter of the center hole of the holder, the rigidity of the clamp is improved. A clamp screw is inserted into a screw hole penetrating vertically on the outer periphery of the cutting tool, and the clamp screw is tightened to shrink the inner diameter of the holder center hole. For this reason, the shrinkage width is small, and a holder of the same size is required for the boring bar, and a boring bar of a different size cannot be attached.

  The holder for the boring bar disclosed in Patent Document 2 is also considered to be the same as the holder for the boring bar disclosed in Patent Document 1, and therefore has the same problems as the holder of Patent Document 1.

  In a holder for a boring tool having a small tip as disclosed in Patent Document 1, when mounted on the tool rest of a machine tool, the holder has no stepped portion to be a stopper, and a boring tool is attached if high resistance machining is performed. The holder moves, leading to deterioration of machining accuracy and chipping of the cutting tool of the boring tool. In addition, the holder with a large holder tip has a built-in clamp screw at the tip, so the length of the tip cannot be shortened. The tip blade cannot be put on because the tip of the holder interferes.

  The present invention improves the stability of fixing a boring bit to a holder when mounted on a tool post of a machine tool as disclosed in the prior art and Patent Document 1.2, and uses a boring bit. The objectives are to improve the accuracy and prevent stable chattering, and to achieve compatibility so that multiple boring bars of different sizes can be attached with a single holder.

Means to solve the problem

  In order to solve the above problems, in the present invention, a sleeve having a slit and a groove is inserted into the center hole of the holder tip, and a shank part of a boring bit is inserted into the center hole of the sleeve, so With four clamp screws incorporated into the sleeve, a slit is formed at one location, and the sleeve with a groove at one location is pressed from the top and bottom to shrink the inner diameter of the sleeve center hole, and the shank portion of the boring bit is Equipped with a fixing function. The sleeve was provided with slits at one location, and a groove at one location was provided in the facing portion to give a shrinkage width so that the sleeve could be further contracted.

  A single holder for boring tools by unifying the outer diameter of sleeves with multiple slits and grooves into the same size, and matching the inner diameter of each sleeve with the shank diameter of each boring tool. The boring bar of different sizes is equipped with a function that can be installed only by replacing the sleeve.

  By making the outer diameter part of the sleeve with slits and grooves into which the boring tool is inserted into the holder center part with a small diameter at the top end of the holder with the clamp screw to be pressed up and down, create a step with the center part of the holder, and at the center part and the rear shank part Also, the rear shank part is composed of multiple steps with a small diameter, and the outer diameter width of the central part where the clamp screw is not installed is made thin. Since the tip of the tool has a small diameter, the holder tip does not interfere even with a machine tool with an external oiling device.Therefore, a cutting fluid with a lubricating effect can be applied to the cutting tool tip, and the rear shank part is more than the center part. Because of its small diameter, the center part is designed to be a stopper when mounted on the tool post of a machine tool.

The invention's effect

  The holder for a boring tool of the present invention has a slit at one location, a sleeve with a groove at one location is inserted into the center hole of the holder, and four clamp screws attached to the top and bottom of the holder. By pressing the diameter portion from above and below, the inner diameter of the center hole of the sleeve contracts, so that the boring bit inserted into the sleeve center hole is fixed. The inner surface of the sleeve center hole adheres to the outer periphery of the shank of the boring bar in a wide area, and there is no gap between the boring bar and the boring bar. Since the holding force is stabilized, chattering of the boring tool during processing is suppressed, and it is possible to prevent chipping of the tip cutter and to perform stable processing. Further, when the groove portion attached to the sleeve is mounted on the tool post of the internal oil supply type machine tool, it becomes a passage for the cutting oil agent, and the cutting oil agent can be applied to the cutting tool tip tool.

  Unify the inner diameter of the holder with the same size, and make the outer diameter of the sleeve with multiple slits and grooves almost the same size (the outer diameter of the sleeve is slightly smaller than the inner diameter of the center hole of the holder so that the sleeve can be inserted and removed smoothly from the holder) By adjusting the inner diameter of each sleeve center hole to the shank size diameter of each size boring tool, it is possible to attach boring tools of different sizes with a single holder only by replacing the sleeve. .

  By simply shrinking the inner diameter of the center hole of the sleeve with slits and grooves and fixing the boring bar, rotation of the boring bar, positioning in the longitudinal direction, and management of the center height become insufficient. Separately from the clamp screw attached to the tip, two clamp screws were attached up and down. Thus, by directly tightening the boring bit shank from above and below, the position in the longitudinal direction can be determined first, and the effects of rotation prevention and center height management can be expected.

  In the holder shape, the tip of the crank screw is made small in diameter to create a step with the center, and the center and rear shank are also composed of multiple steps with a step that makes the rear shank smaller. The outer diameter width of the part was made thin. For this reason, when the holder is mounted on the tool post of the machine tool, the tip part has a small diameter, so in the machine tool of the external lubrication device, the cutting fluid can be applied to the boring tool tip tool, and the center part is the holder rear shank part. Since the diameter of the holder is larger than that of the tool post, the insertion length of the holder with respect to the tool post can be made constant, and a stopper is provided to prevent the holder from moving during processing with high resistance. In addition, when the holder tip has a small diameter, the processing restrictions due to the workpiece size and machining shape are relaxed, and in multi-step inner diameter processing, the holder inner small diameter part is inserted inside the first inner diameter of the workpiece and the next inner diameter is processed. It became possible. If such processing is possible, it becomes possible to reduce chatter during processing by reducing the protruding amount of the boring bar from the tip of the holder. By making the holder tip small, the tip of the holder can be inserted into the raw nail with the chuck mate without interference even when molding a raw nail chuck that clamps the workpiece with an NC lathe, so that the deep nail chuck can be molded deeply. It is.

  Embodiments of a holder of the present invention and a boring tool using the holder will be described with reference to FIGS. 1 is a perspective view showing an example of the holder, FIG. 2 is a plan view of the holder, and FIG. 3 is a front view of the holder. The holder is formed of a holder body (1), a sleeve (2), clamp screws (4) (5) (7) (8) for pressing the sleeve, and (6) (9) for positioning the boring bar.

  As shown in FIGS. 1 and 2, the holder main body has a small diameter portion (1a) at the tip portion, a rear shank portion to be inserted into the tool rest of the machine tool (1b), and a central large diameter portion connected from the tip small diameter portion to the rear shank side. (1c) is a multistage structure. The holder rear shank side (1b) is provided with a flattening portion (10) for mounting on the tool post of the machine tool. A central hole (11) penetrating in the axial direction is provided at the center of the sleeve body.

  The holder center hole (11) is a hole having substantially the same diameter as the sleeve outer diameter slightly larger than the sleeve outer diameter in order to smoothly insert and remove the sleeve (2) shown in FIGS.

  1, 4, and 5, the inner diameter of the sleeve (3) is slightly larger than the outer diameter of the boring bar shank (13) so that the boring bar (12) can be inserted and removed smoothly. It is almost the same diameter as the outer diameter.

  Clamp screws (4), (5), (7) and (8) for tightening the sleeve (2) are screwed into the upper and lower surfaces of the holder body tip small diameter portion (1a) so as to penetrate the center hole (11).

  Clamp screws (6) and (9) for positioning the boring bar (12) are screwed into the upper and lower surfaces of the holder main body rear part (1b) so as to penetrate the center hole (11).

  Insert the sleeve (2) into the center hole (11) of the holder body (1), and clamp the sleeve (2) with the clamp screws (4), (5), (7), (8) assembled at the top and bottom of the holder tip small diameter part (1a). By pressing from above and below, the bore diameter (13) inserted into the sleeve center hole (3) is firmly fixed by contracting the inner diameter of the sleeve center hole (3).

  4 to 6 show a boring tool holder (15) configured by fixing the boring tool (12) with the holder body described above. In the boring bar (12), a flattening portion (14) is provided on the outer periphery of the shank portion (13) over the entire length of the shank portion. By tightening the boring bit shank flat part (14) up and down with the clamp screw (6) (9) for positioning mounted on the rear shank part (1b) of the holder body (1) up and down, the boring bit (12) It is installed so that positioning can be performed.

  Since the tip (1a) of the holder body (1) has a small diameter and the center (1c) has a larger diameter than the holder rear shank (1b), the center (1c) is attached to the tool post of the machine tool. Sometimes it becomes a stopper, and the insertion length of the holder can be made constant. Also, the holder body does not move even when processing with high resistance is performed.

  As shown in FIG. 4, the holder body (1) has a small diameter at the tip of the holder (1a), so if the tip is smaller than the workpiece hole, the tip of the holder is inserted into the workpiece hole for processing. Can do. The amount of protrusion of the boring bar (12) from the holder tip can be reduced to suppress chatter during processing.

  As shown in FIG. 4, the holder (1) has a small diameter at the tip (1a) of the holder and the width of the central portion (1b) serving as a stopper, so that the machine tool with an external oiling device is provided. However, since the holder tip does not interfere, the cutting oil can be applied to the boring tool tip tool, and the life of the boring tool (12) can be increased by the lubricating effect and the cooling effect.

  When the groove (2b) attached to the sleeve is mounted on the tool post of an internal oil supply type machine tool, it becomes a passage for the cutting oil, and the cutting oil can be applied to the cutting tool of the boring bit (12).

  By exchanging sleeves having different inner diameter sizes of the sleeve center hole (3), boring tools (12) of different sizes can be attached.

  By using the holder (1) of the present invention for inserting the sleeve (2) having slits and grooves into the holder center hole (11) and fixing the boring bit (12) inserted into the sleeve center hole (3), A plurality of boring tools (12) of different sizes can be attached by the holder (1), and chatter during processing can be suppressed and stable processing is possible.

Perspective view of invention holder Plan view of invention holder Front view of invention holder 1 is a perspective view of a boring tool incorporated in the holder of FIG. AA sectional view of FIG. BB sectional view of FIG. Usage diagram

DESCRIPTION OF SYMBOLS 1 Holder 1a Holder front-end | tip part 1b Holder back part 1c Holder center part 2 Sleeve 2a Sleeve slit part 2b Sleeve groove part 3 Sleeve center hole 4 Clamp screw 5 Clamp screw 6 Clamp screw 7 Clamp screw 8 Clamp screw 9 Clamp screw 10 Holder flat part 11 Holder center hole 12 Boring bit 13 Boring bit shank part 14 Boring bit flat part 15 Holder (with boring bit)

Claims (4)

  In a boring tool holder (1) for inserting a boring tool shank portion (13) into a holder central hole (11) and fixing the shank portion of a boring tool (12) (hereinafter abbreviated as a boring tool) used for inner diameter processing. , A slit (2a) is provided at one position in the center hole (11) at the tip of the holder, and a sleeve (2) having a groove (2b) at one position is inserted into the opposite face, and the sleeve center hole (3) is inserted. Insert the boring tool shank part (13) and insert the sleeve (2) with slits and grooves into the four clamp screws (4), (5), (7), and (8) incorporated in the tip of the holder (1a). By pressing from above and below, the inner diameter of the sleeve center hole (3) is shrunk, so that the shank part of the boring bit is fixed, and the rear shank part of the holder By tightening boring flat chamfer (14) from above and below by two clamping screws attached to 1b) (6) (9), anti-rotation of the boring tool (12), boring tool holder for center height Management   By attaching one groove (2b) to the facing part of the slit (2a), the inner diameter shrinkage of the sleeve center hole (3) is greatly increased when pressing from above and below with the clamp screws (4) (5) (7) (8). The holder for a boring tool according to claim 1, wherein a sleeve (2) used as a passage for cutting fluid can be attached to the groove (2b).   By integrating the outer diameter of the sleeve (2) with a plurality of slits and grooves into the same dimension, and adjusting the inner diameter of each sleeve center hole (3) to the diameter of the boring bit shank (13) of each size, the slit The boring bar holder according to claim 1 or 2, wherein the boring bar (12) of different sizes can be attached only by replacing the grooved sleeve (2).   A tip end (1a) to which a clamp screw (4) (5) (7) (8) is fixed by pressing a sleeve (2) with a slit and groove into which a boring bit shank (13) is inserted from above and below. ) Is made smaller in diameter so that a step is formed with the central portion (1c), and the central portion (1c) and the rear shank portion (1b) are also made up of multiple steps with steps that make the rear shank portion (1b) smaller in diameter. The holder for a boring tool according to claims 1 to 3, wherein the outer diameter width of the center part (1c) of the holder, which serves as a stopper for the boring tool holder (1), is reduced when mounted on the tool post of the machine tool.

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