JP2006326744A - Chuck pawl of chuck mechanism for lathe - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a chuck pawl capable of high-precision alignment by adjusting an eccentric volume of a rotary axial line of a workpiece at high accuracy by economically-excellent means with a simple structure, or adjusting small misalignment. <P>SOLUTION: This chuck pawl 1 divided into a chuck pawl body 10 and a chuck tip 20 comprises a screw hole and a slit for a bolt inserting the chuck pawl body 10 in a vertical direction against a rotary axial line X, a bolt fixing hole extending the chuck pawl tip 20 to the slit, and an adjusting screw bolt screwed with the screw hole for the bolt, and adjusting a spacing volume between a first wall of a step part and an opposed face 20A of the chuck pawl tip 20. In this chuck pawl for a chuck mechanism for a lathe, a fixing bolt is fastened between the bolt fixing hole 21 and the slit, and the chuck pawl tip 20 is fixed to the chuck pawl body 10 while keeping the spacing. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a chuck mechanism for chucking a workpiece when the workpiece is eccentrically processed or centered using a lathe, in particular, a chuck claw structure having a simple structure capable of adjusting the position of the gripping surface of the chuck claw. About.

  Usually, a lathe is used for external processing of various shapes of rod-shaped or cylindrical workpieces. In a lathe, the workpiece is chucked by a chuck mechanism, but in some cases, the workpiece is required to be eccentrically processed. In this case, the work must be chucked in a state where the work is eccentric by a predetermined amount. Various techniques for chucking in a state where the workpiece is eccentric by a predetermined amount have already been proposed. For example, a cylinder device or the like moves the chuck mechanism up and down, left and right according to the required amount of eccentricity (for example, see Patent Document 1), or forms a plurality of step portions on the chuck surface of the chuck claw. In addition, there has been proposed one that chucks a workpiece by selecting a stepped portion according to a necessary amount of eccentricity (for example, see Patent Document 2).

A chuck claw eccentric mechanism is also disclosed in which the chuck claw is divided into a claw body portion and a claw tip portion, and the claw tip portion is moved in accordance with a required amount of eccentricity (see, for example, Patent Document 3). Furthermore, an invention that discloses a structure that solves a decrease in machining accuracy due to lifting of the chuck claw by a chuck mechanism that grips or releases the workpiece by reducing or expanding the diameter of the chuck claw (see, for example, Patent Document 4). It has already been proposed.
Japanese Patent Laid-Open No. 01-011702 JP 04-269105 A JP 2003-175411 A Japanese Patent Laid-Open No. 08-155707

  The chuck mechanism disclosed in Patent Document 1 has an eccentric structure that moves the entire chuck mechanism including the chuck claws according to the required eccentric amount. Therefore, the structure is complicated and large, and the cost increases. There is. Further, the chuck mechanism disclosed in Patent Document 2 has a structure in which a step is formed on the chuck surface itself of the chuck claw and is eccentric using the step portion, so there are several adjustable eccentric amounts. Therefore, there is a problem that the processing accuracy is inevitably lowered because a desired amount of eccentricity cannot be obtained. There is also a problem that the chucked portion of the workpiece to be chucked by the step to be attached is displaced by the width of the step.

  The chuck eccentric mechanism disclosed in Patent Document 3 has a structure in which two pieces are attached to the tip portion of the chuck claw and the two pieces are shifted on the sliding surface to obtain a desired amount of eccentricity. A structure that slides in the direction of the axis of rotation while fixing the two tops to the tip is necessary, and when the workpiece is chucked, the chuck claw is naturally subjected to pressure, so the life is short and accuracy is maintained. There are problems such as difficult maintenance. Further, since the structure is relatively complicated and the two pieces are shifted in the direction of the rotation axis to be eccentric, an excessive pressure may be applied, and the eccentricity may be difficult to maintain. In addition, the above-mentioned Patent Document 4 solves the problem of lifting of the chuck claw that occurs on the chuck mechanism by attaching the tip claw to the claw body, and does not disclose the structure of the chuck claw that chucks the workpiece eccentrically. .

  The present invention solves such problems and adjusts the eccentricity of the rotation axis passing through the center of the rotation axis of the workpiece in the lathe with high accuracy by means having a simple structure and excellent economy, or the center point of the chuck claw It is an object of the present invention to provide a chuck claw of a chuck mechanism that can adjust a minute positional deviation with respect to a rotation axis of a workpiece and perform high-precision centering.

  In order to solve the above-mentioned problem, the first invention is a plurality of chuck claws for gripping or releasing the workpiece by moving in a direction perpendicular to the rotation axis of the workpiece to be lathe and reducing or expanding the diameter. A chuck in which at least one of the chuck claws in a lathe chuck mechanism provided with a chuck is attached to a step portion having a chuck claw main body portion and two orthogonal first and second wall surfaces formed in the chuck claw main body portion. A chuck claw comprising a claw tip portion, a bolt screwing hole extending through the chuck claw main body portion to the first wall surface of the step portion in a direction perpendicular to the rotation axis, and the chuck claw main body. An elongated hole extending in the same direction as the rotation axis from the second wall surface in the stepped portion of the portion, and the elongated hole extending in the same direction as the rotation axis along the chuck claw tip A bolt fixing hole extending at a position, and a screw engaging hole for the bolt, and a tip projecting from the first wall surface of the stepped portion in the chuck claw main body and abutting on the chuck claw tip. An adjusting screw for adjusting a gap amount between the first wall surface of the stepped portion and a facing surface of the chuck claw tip portion facing the wall surface, and the first step of the stepped portion. With the gap between the wall surface and the opposing surface of the chuck claw tip held, the gap between the bolt fixing hole and the elongated hole is tightened with a fixing bolt to fix the chuck claw tip to the chuck Provided is a chuck claw for a lathe chuck mechanism, wherein the chuck claw is fixed to the second wall surface of the stepped portion in the claw body.

  A second invention is a lathe chuck mechanism comprising a plurality of chuck claws that grip or release the workpiece by moving in a direction perpendicular to the rotation axis of the workpiece to be lathe and reducing or expanding the diameter. Then, at least one of the chuck claws includes a chuck claw main body portion and a chuck claw tip portion attached to a step portion having two orthogonal first and second wall surfaces formed on the chuck claw main body portion. In the chuck claw, a bolt screw hole extending through the chuck claw main body portion in a direction perpendicular to the rotation axis to the first wall surface of the step portion, and the step portion of the chuck claw main body portion. A long hole extending from the second wall surface in the same direction as the rotation axis and penetrating the chuck claw tip to the long hole in the same direction as the rotation axis. And an adjustment spacer having a through hole and a thickness equal to a set eccentricity amount, and a screw threaded engagement with the bolt threading hole, and a tip projecting from the first wall surface of the stepped portion in the chuck claw body. A screw bolt that extends into the through hole of the adjustment spacer, and the gap between the first wall surface of the stepped portion and the opposing surface of the tip end portion of the chuck claw is set to the set eccentric amount. In the held state, the tip of the chuck claw is fixed to the second wall surface of the step portion of the chuck claw main body by tightening between the bolt fixing hole and the elongated hole with a fixing bolt. Provided is a chuck claw of a lathe chuck mechanism.

  A third invention is a lathe chuck mechanism comprising a plurality of chuck claws that grip or release the workpiece by moving in a direction perpendicular to the rotation axis of the workpiece to be lathe and reducing or expanding the diameter. Then, at least one of the chuck claws includes a chuck claw main body portion and a chuck claw tip portion attached to a step portion having two orthogonal first and second wall surfaces formed on the chuck claw main body portion. In the chuck claw, a long hole extending in the same direction as the rotation axis from the second wall surface in the stepped portion of the chuck claw main body and penetrating the chuck claw tip in the same direction as the rotation axis. A bolt fixing hole extending to the long hole, and an adjustment spacer made of a magnetic material and having a thickness equal to the set eccentricity, and the first wall surface and the chuck of the stepped portion. With the gap between the opposing surface of the claw tip portion held at a preset eccentric amount, the bolt fixing hole and the elongated hole are tightened with a fixing bolt, and the chuck claw tip portion is Provided is a chuck claw for a lathe chuck mechanism, wherein the chuck claw main body is fixed to the second wall surface of the stepped portion.

  A fourth invention is a lathe chuck mechanism comprising a plurality of chuck claws for gripping or releasing the workpiece by moving in a direction perpendicular to the rotation axis of the workpiece to be lathe to reduce or expand the diameter. Then, at least one of the chuck claws includes a chuck claw main body portion and a chuck claw tip portion attached to a step portion having two orthogonal first and second wall surfaces formed on the chuck claw main body portion. In the chuck claw, a bolt screw hole extending through the chuck claw main body portion in a direction perpendicular to the rotation axis to the first wall surface of the step portion, and the step portion of the chuck claw main body portion. A long hole extending from the second wall surface in the same direction as the rotation axis and penetrating the chuck claw tip to the long hole in the same direction as the rotation axis. An adjustment spacer having a thickness for adjusting a gap between the first wall surface of the stepped portion and a facing surface of the chuck claw tip portion facing the wall surface, and screwed into the bolt screw hole. And an adjustment screwing bolt that protrudes from the first wall surface of the step portion of the chuck claw body portion and abuts against the adjustment spacer, and the first wall surface of the step portion and the chuck In a state where the gap between the opposing surface of the claw tip portion is maintained, the chuck claw tip portion of the chuck claw main body portion is tightened with a fixing bolt between the bolt fixing hole and the elongated hole. Provided is a chuck claw for a lathe chuck mechanism, which is fixed to the second wall surface of the stepped portion.

  A fifth invention is a lathe chuck mechanism including a plurality of chuck claws that grip or release the workpiece by moving in a direction perpendicular to the rotation axis of the workpiece to be lathe and reducing or expanding the diameter. Then, at least one of the chuck claws includes a chuck claw main body portion and a chuck claw tip portion attached to a step portion having two orthogonal first and second wall surfaces formed on the chuck claw main body portion. In the chuck claw, a bolt threading hole that extends through the chuck claw main body portion in a direction perpendicular to the rotation axis to the first wall surface of the stepped portion and penetrates the chuck claw main body portion, and the chuck claw tip portion extends through the rotation axis. A bolt fixing hole extending in the same direction, a bolt insertion hole extending in a direction perpendicular to the axis of rotation of the chuck claw tip and intersecting the fixing hole, and the bolt screwing And the tip portion protrudes from the first wall surface of the stepped portion in the chuck claw main body portion and extends to the bolt insertion hole so as to face the first wall surface of the stepped portion and the wall surface. An adjustment screw for adjusting a gap between the opposing surface of the claw tip portion and the gap between the first wall surface of the step portion and the opposing surface of the chuck claw tip portion. A chuck of a lathe chuck mechanism, wherein the chuck pin is fixed to the screw bolt by tightening the tip portion of the screw bolt with a fixing bolt from the bolt fixing hole. Offer nails.

  A sixth invention is a lathe chuck mechanism provided with a plurality of chuck claws that grip or release the workpiece by moving in a direction perpendicular to the rotation axis of the workpiece to be lathe and reducing or expanding the diameter. Then, at least one of the chuck claws includes a chuck claw main body portion and a chuck claw tip portion attached to a step portion having two orthogonal first and second wall surfaces formed on the chuck claw main body portion. In the chuck claw, a bolt threading hole that extends through the chuck claw main body portion in a direction perpendicular to the rotation axis to the first wall surface of the stepped portion and penetrates the chuck claw main body portion, and the chuck claw tip portion extends through the rotation axis. A bolt fixing hole extending in the same direction, a bolt insertion hole extending in a direction perpendicular to the rotation axis of the chuck claw tip and intersecting the fixing hole, and a through hole And an adjustment spacer having a thickness equal to the set eccentric amount and the bolt screw hole, and a tip portion protrudes from the first wall surface of the step portion in the chuck claw main body portion. A screw bolt that is inserted into the bolt insertion hole through the through hole of the spacer, and the gap between the first wall surface of the stepped portion and the opposing surface of the tip end portion of the chuck claw is defined as the gap. A chuck of a lathe chuck mechanism, wherein the chucking bolt is fastened with a fixing bolt from the bolt fixing hole in a state of being held at a set eccentric amount, and a tip end portion of the chuck claw is fixed to the screwing bolt. Offer nails.

  According to the first invention, prior to the lathe machining operation, the eccentric amount of the rotation axis passing through the rotation center of the workpiece in the lathe is adjusted with high accuracy by a simple and economical means, or the rotation axis of the workpiece is adjusted. High-precision centering can be easily performed by adjusting a minute positional deviation.

  According to the second aspect of the present invention, the rotation axis passing through the center of rotation of the work in the lathe can be easily and quickly decentered with a relatively large set eccentricity by simple and economical means. Can do.

  According to the third aspect of the present invention, the amount of eccentricity of the rotational axis passing through the center of rotation of the work in the lathe can be easily and shortly set by a very simple and economical means even for a predetermined large set value. You can make adjustments in time.

  According to the fourth aspect of the present invention, the amount of eccentricity of the rotation axis passing through the center of rotation of the workpiece in the lathe can be easily and quickly set by a simple and economical means even for a predetermined large set value. Adjustment can be made with high accuracy.

  According to the fifth aspect of the present invention, the amount of eccentricity of the rotation axis passing through the center of rotation of the work in the lathe can be easily and without shifting to the left and right and front and rear by a simple and economical means. Adjustments can be made with high accuracy in a short time.

  According to the sixth aspect of the invention, the eccentric amount of the rotation axis passing through the center of rotation of the work in the lathe is shifted to the left and right and back and forth with a simple and economical means even with respect to a predetermined large set value. Therefore, the adjustment can be easily performed with high accuracy in a short time.

[Embodiment 1]
First, a chuck claw of a lathe chuck mechanism according to Embodiment 1 of the present invention will be described with reference to FIGS. FIG. 1 shows an outline of the overall structure of a lathe chuck mechanism according to the present invention, and FIG. 2 is a diagram for explaining an eccentric range of a rotation axis X passing through a center point of a rotation axis of a workpiece chucked by the chuck mechanism. FIG. 3 is a view showing main members constituting the chuck claw according to the improvement of the present invention. FIG. 4 is a view for explaining the chuck claw according to the first embodiment, and FIG. 5 is a view showing a partial cross section for explaining the chuck claw.

  In FIG. 1, three chuck claws 1, 2, and 3 are attached to the chuck body 4 at regular intervals, that is, 120 degree intervals, as in a normal lathe chuck mechanism. 3 can move in the radial or radial direction, that is, in the vertical direction with respect to the center line of the rotation axis (hereinafter referred to as the rotation axis X). Here, the direction in which the three chuck claws 1, 2, and 3 approach each other is referred to as advance, and the direction in which they are separated from each other is referred to as retreat. Further, when the three chuck claws 1, 2, and 3 move forward, the diameters of the virtual circles formed by the curved gripping surfaces A, B, and C, which are the front end surfaces thereof, are reduced, and this is referred to as a reduced diameter. To tell. When the three chuck claws 1, 2, and 3 are retracted, the diameter of the virtual circle formed by the gripping surfaces A, B, and C increases, and this is called diameter expansion. Note that the number of chuck claws is not limited to three, and it is a matter of course that an appropriate number of chuck claws such as two or four may be arranged on the chuck body 4 at equal intervals.

  In the present invention, as shown in FIG. 2, the rotation axis X passing through the center point of the rotation axis of the workpiece W to be turned with respect to the rotation center point x of the lathe can be decentered, or three chuck claws 1 At least one of the three chuck claws 1 to 3 so as to adjust a minute misalignment with the rotation axis X of the work W with respect to the rotation center point x of the lathe caused by the adjustment of .about.3. Only the chuck claw 1 is divided into a chuck claw body 10 and a chuck claw tip 20. As shown in FIG. 3, the chuck claw body 10 includes a step portion 11 formed by two first wall surfaces 10A and a second wall surface 10B orthogonal to each other, and a third wall surface 10C facing the first wall surface 10A. A bolt screw hole 12 extending to the first wall surface 10 </ b> A, a sliding groove 13 for allowing the chuck claw 1 to slide relative to the chuck body 4, and extending from the second wall surface 10 </ b> B to the sliding groove 13. It has a long hole 14 penetrating therethrough. The long hole 14 is elongated in the same direction as the direction in which the bolt screw hole 12 extends. The chuck claw tip 20 has a bolt fixing hole 21 that communicates with the elongated hole 14 of the chuck claw body 10, a gripping surface A, and a wall surface 20 A that faces the first wall surface 10 A of the chuck claw body 10. The gripping surface A of the chuck claw tip 20 protrudes from the tip surface 10D of the chuck claw main body 10 so that a workpiece (not shown) can be chucked with the gripping surfaces B and C of other chuck claws.

  The chuck claw 1 includes an adjustment screw 30 that is screwed into the bolt screw hole 12 of the chuck claw body 10. The screw bolt 30 has a male screw portion 30A in which threads are formed at a constant pitch on the outer surface of a cylindrical shaft, and the male screw portion 30A is formed in the screw screw hole 12 of the chuck claw body 10. It engages with a female screw portion (not shown). The screw bolt 30 is appropriately longer than the length between the first wall surface 10 </ b> A and the third wall surface 10 </ b> C of the chuck claw body 10, and the screw bolt 30 is screwed into the screw screw hole 12. By doing so, the tip surface 30B advances or retreats little by little. Therefore, the tip end face 30B of the screwing bolt 30 can be protruded from the first wall surface 10A of the chuck claw body 10 by an appropriate length by appropriately turning the screwing bolt 30 in a certain rotation direction. The screw bolt 30 is preferably made of a metal material having a small coefficient of thermal expansion that is not deformed by the applied pressure and is difficult to change in length due to a temperature change. The screw bolt 30 is held in a fixed state by a fixing nut 40. The fixing nut 40 is not always necessary.

  Further, the chuck claw 1 includes a fixing bolt 50 that fixes the chuck claw tip 20 to the stepped portion 11 of the chuck claw main body 10, particularly the second wall surface 10 </ b> B, and a fixing nut 60 having a quadrangular outer shape. The fixing bolt 50 is screwed into a fixing nut 60 housed in the sliding groove 13 through the bolt fixing hole 21 of the chuck claw tip 20 and the long hole 14 of the chuck claw body 10. As shown in FIG. 4, the bottom of the sliding groove 13 around the long hole 14 is deeper, and the fixing nut 60 is stored in the deepened portion so as not to rotate. The front end portion of the working bolt 50 does not protrude into the sliding groove 13.

  The chuck claw 1 according to the first embodiment, which can easily adjust the eccentric amount of the rotation axis X of the workpiece W, will also be described with reference to FIGS. 4 and 5. The eccentric amount set by previously screwing the screw bolt 30. Move forward more than. That is, the tip end portion of the screw bolt 30 is protruded from the first wall surface 10A so as to be longer than the set eccentric amount. At this time, the fixing bolt 50 that is shallowly screwed into the fixing nut 60 through the bolt fixing hole 21 can move up and down in the drawing in the elongated hole 14, and the fixing nut 60 is in the sliding groove 13. Since the deep groove portion 13A formed around the long hole 14 can move up and down in the drawing, the forward movement and backward movement of the chuck claw tip 20 are not hindered. First, the chuck claw 1 having the structure of the first embodiment and the chuck claws 2 and 3 having a normal structure are advanced to chuck the workpiece W to be lathe processed with a predetermined pressure. In this state, as shown in FIGS. 4 and 5, when the screw bolt 30 is retracted to adjust the eccentricity of the rotation axis X of the workpiece W to the set eccentricity, the first wall surface 10 </ b> A in the step portion 11. The tip surface 30B of the screw bolt 30 that protrudes from the chuck claw 20 and pushes the wall surface 20A of the chuck claw tip 20 downward is retracted. The gripping surface A of the part 20 moves in the upward direction in the drawing.

  Here, the amount of misalignment of the rotation axis X of the work W with respect to the center of rotation x of the lathe may be about 0.01 mm, and high accuracy may be required. The thread pitch of the male threaded portion 30A in the threaded bolt 30 is small so that both the above adjustment and the amount of eccentricity can be adjusted. By rotating the screw bolt 30 until the runout of the rotation axis X becomes zero by a measuring instrument (not shown), the gripping surface A of the chuck claw tip 20 moves upward in the drawing, and the runout is zero. That is, when the set eccentric amount is reached, the screwing bolt 30 is stopped from being screwed, and the fixing bolt 50 is strongly screwed to the fixing nut 60 so that the chuck claw tip 20 is engaged with the wall surface 10B of the step portion 11. Secure firmly. At this time, the fixing nut 40 is brought into contact with the wall surface 10C of the chuck claw body 10 as necessary. According to this embodiment, even if the chuck claws 1 to 3 are retracted to open the workpiece W and another workpiece similar to the workpiece W is chucked by the chuck claws 1 to 3, The rotation axis can be decentered by a set amount of eccentricity. According to the first embodiment, the desired length shown in FIG. 2 can be obtained simply by adjusting the protrusion length d of the screw bolt 30 protruding from the wall surface 10A of the step portion 11 of the chuck claw body 10 at the tip portion of the screw bolt 30. Not only can the rotation axis of the workpiece W be easily decentered in the eccentric range, but also misalignment can be easily adjusted in the same manner.

[Embodiment 2]
Next, another embodiment of the chuck claw 1 will be described with reference to FIG. The screw bolt 30 in the first embodiment worked for adjusting the position of the rotation axis X, but the chuck claw 1 in the second embodiment has an adjustment spacer 70 that decenters the rotation axis X of the workpiece W by a set eccentric amount. There are features. In FIG. 6, the same symbols as those used in FIGS. 4 and 5 indicate members having the same names. Since the structure of the members 10 to 60 is the same as that described above, the description thereof is omitted. The chuck claw 1 of the second embodiment is suitable when the amount of eccentricity is determined in advance, and the adjustment spacer 70 shown in FIG. 6 is a rectangular or round flat plate shape such as a quadrangle. 3 is inserted between the first wall surface 10A of the chuck claw body 10 and the wall surface 20A of the chuck claw tip 20 in FIG. The adjustment spacer 70 has a thickness d that can decenter the rotation axis of the workpiece W by a set eccentric amount, that is, a thickness d equal to the set eccentric amount, and has a through hole 70A that receives the tip portion of the screw bolt 30. Have.

  When the adjustment spacer 70 is disposed between the first wall surface 10A of the stepped portion 11 of the chuck claw body 10 and the wall surface 20A of the chuck claw tip 20 facing the wall surface, the fixing bolt 50 and the fixing bolt 50 are fixed. The screwed state with the nut 60 is made shallow so that the fixing bolt 50 can move up and down in the drawing. Further, the screw bolt 30 has the first wall surface of the chuck claw body 10 to such an extent that the adjustment spacer 70 can be mounted between the first wall surface 10A of the chuck claw body 10 and the wall surface 20A of the chuck claw tip 20. You may protrude from 10A (FIG. 3). In a state where the adjustment spacer 70 is mounted between the first wall surface 10A of the chuck claw body 10 and the wall surface 20A of the chuck claw tip portion 20, first, the chuck claw 1 having the structure of the second embodiment and the chuck having the normal structure are used. The claws 2 and 3 are moved forward to chuck the workpiece W to be turned with a predetermined pressure. In this state, the distance between the first wall surface 10A of the chuck claw main body 10 and the wall surface 20A of the chuck claw tip 20 opposite thereto is equal to the thickness d of the adjustment spacer 70, and the rotation axis X of the workpiece W is Set eccentricity. In this state, the fixing bolt 50 is screwed into the fixing nut 60 to firmly fix the chuck claw tip 20 to the second wall surface 10B of the step portion 11.

  At this time, the front end surface 30B of the screwing bolt 30 may be in contact with the wall surface 20A (FIG. 3) of the chuck claw front end portion 20 or may be inserted into the through hole 70A of the adjustment spacer 70. In the second embodiment, the screwing bolt 30 acts so that the adjusting spacer 70 does not come off during operation or does not deviate so much. The adjustment spacer 70 may be a spacer having the same thickness or a stack of a plurality of spacers having different thicknesses. For example, when the thickness d is 0.3 mm, three spacers with a thickness of 0.1 mm are stacked, or when the thickness d is 0.6 mm, one spacer with a thickness of 0.5 mm and a thickness of 0.1 mm. It may be a stack of one spacer. In particular, when the adjustment spacer 70 is formed by stacking a plurality of thin spacers, the tip surface 30B of the screw bolt 30 is in contact with the wall surface 20A of the chuck claw tip 20 (FIG. 3). This is preferable from the viewpoint that the stacked spacers do not come off. The chuck claw 1 of the second embodiment is particularly effective when the amount of eccentricity is relatively large or when the amount of eccentricity is determined in advance. Since the other structure is the same as described above, the description is omitted. However, when the adjustment spacer 70 is made of a magnetic material, the adjustment spacer 70 itself is the wall surface 10A of the chuck claw body 10 or the chuck. Since it adsorbs to the wall surface 20A of the claw tip portion 20, the adjustment spacer 70 is not removed or displaced. Therefore, the screw bolt 30 and the screw screw hole 12 are not necessarily required. In this case, the adjustment spacer 70 may not have the through hole 70A.

[Embodiment 3]
Next, Embodiment 3 of the chuck claw 1 will be described with reference to FIGS. 7 and 8, the same symbols as those used in FIGS. 4 to 6 indicate members having the same names. The chuck claw 1 according to the third embodiment is characterized in that it is performed by an adjustment spacer 70 for adjusting the most eccentric amount of the set eccentric amount, and the remaining small eccentricity is finely adjusted by the screw bolt 30. Since the structures of the members 10 to 60 are substantially the same as described above, the description thereof is omitted. The chuck claw 1 of the third embodiment is suitable for a case where the eccentric amount is relatively large and the eccentric amount needs to be adjusted. The adjusting spacer 70 shown in FIGS. 7 and 8 has an outer shape such as a square shape. It is a square or round flat plate, and is inserted between the wall surface 10A of the chuck claw body 10 and the wall surface 20A of the chuck claw tip 20 in FIG. The adjustment spacer 70 has a thickness d1 that is thinner than a thickness d that can decenter the rotation axis X of the workpiece W by a set eccentric amount. A through hole 70 </ b> A for receiving the small diameter portion 30 </ b> C at the tip of the screw bolt 30 is provided. As shown in FIGS. 7 and 8, the center of the tip of the screw bolt 30 is a small diameter portion 30C. The small diameter portion 30C has a diameter smaller than the diameter of the through hole 70A of the adjustment spacer 70, and the diameter of the through hole 70A of the adjustment spacer 70 is the diameter of the screw bolt 30 excluding the small diameter portion 30C (hereinafter referred to as the diameter). Smaller than the normal diameter). The end surface of the normal diameter is 30D (FIG. 8). Further, the length of the small diameter portion 30 </ b> C must be equal to or less than the thickness of the adjustment spacer 70.

  The adjustment of the eccentric amount of the rotation axis X of the workpiece W will be described. The adjustment spacer 70 is formed between the first wall surface 10A of the step portion 11 in the chuck claw body 10 and the wall surface 20A of the chuck claw tip portion 20 facing this. After that, the screw bolt 30 is pre-twisted so that the small diameter portion 30C is inserted into the through hole 70A of the adjustment spacer 70, and is further advanced so that the end face 30D of the screw bolt 30 is the upper surface of the adjustment spacer 70. Abut. Then, the screw bolt 30 is further advanced, and the interval between the wall surface 10A of the stepped portion 11 and the surface 70B of the adjustment spacer 70 in the chuck claw body 10 is increased to be larger than the interval d1 exhibiting the set eccentricity. As described in the first embodiment, the workpiece W is chucked by the chuck claws 1 to 3 with an appropriate pressure in this state. In the chucked state, the screw bolt 30 is screwed, and the distance d between the wall surface 10A of the stepped portion 11 and the wall surface 20A (FIG. 3) of the chuck claw tip 20 in the chuck claw main body 10 becomes a set eccentric amount. The screw bolt 30 is moved backward until At this time, the distance between the first wall surface 10A of the step portion 11 in the chuck claw body 10 and the surface 70B of the adjustment spacer 70 is d2, and the first wall surface 10A of the step portion 11 in the chuck claw body 10 and the tip of the chuck claw. The distance d between the portion 20 and the wall surface 20A (FIG. 3) is (d1 + d2). In this embodiment, the distance d1 is smaller than the thickness d2 of the adjustment spacer 70, and the screw bolt 30 is moved backward little by little to finely adjust to obtain a large set eccentricity with high accuracy. In this embodiment as well, when the adjustment spacer 70 is made of a magnetic material and the adjustment spacer 70 itself is attracted to the wall surface 20A of the chuck claw tip portion 20, the adjustment spacer 70 is removed or displaced. Therefore, the screw bolt 30 is not always necessary. In this case, the adjustment spacer 70 may not have the through hole 70A.

[Embodiment 4]
Next, Embodiment 4 of the chuck claw 1 will be described with reference to FIG. 9, the same symbols as those used in FIGS. 4 to 8 indicate members having the same names. As in the first embodiment, the chuck claw 1 according to the fourth embodiment adjusts the eccentric amount or displacement of the rotation axis X by the forward and backward movement of the screw bolt 30, and attaches the chuck claw tip 20 to the screw bolt 30. It is characterized by fixing. Unlike the chuck claw 1 of the first to third embodiments, the chuck claw body 10 in the chuck claw 1 of the fourth embodiment does not have the long hole 14 and the deep groove portion 13A in the stepped portion 11 thereof. Further, the chuck claw tip 20 has a bolt insertion hole 22 that is substantially coaxial with the bolt screwing hole 12 of the chuck claw main body 10, and the bolt fixing hole 21 extends to the bolt insertion hole 22.

  In the fourth embodiment, a screw bolt 30 as shown in FIG. 3 is screwed to the bottom surface 22A of the bolt insertion hole 22 of the chuck claw tip 20 in the vicinity or to the vicinity thereof, and is fixed to the bolt fixing hole 21 on the other side. The bolts 50 are screwed together, and the side surfaces of the tip portions of the screw bolts 30 are tightened at the tips. In this state, since the chuck claw tip 20 is fixed to the screw bolt 30 by the fixing bolt 50, the chuck claw tip 20 is moved downward or forward by screwing the screw bolt 30 forward or backward. Move in the direction or upward. Therefore, the distance between the first wall surface 10A of the chuck claw main body 10 and the wall surface 20A of the chuck claw tip 20 facing it can be easily adjusted by screwing the screw bolt 30 forward or backward. Since the chuck claw tip 20 need not be fixed to the chuck claw body 10 with the fixing bolt 50 after the adjustment, the position of the rotation axis X can be adjusted more easily, and the chuck claw tip 20 can be operated by the bolt insertion hole 22. Therefore, it is possible to prevent a positional deviation between the left and right sides and the front and rear of the drawing, so that highly accurate position adjustment is possible.

[Embodiment 5]
Next, Embodiment 5 of the chuck claw 1 will be described with reference to FIG. 10, the same symbols as those used in FIGS. 4 to 9 indicate members having the same names. The chuck claw 1 according to the fifth embodiment uses the adjusting spacer 70 having a thickness that can adjust the eccentric amount of the rotation axis X to the set eccentric amount d as in the second embodiment, and the screw bolt 30 as in the fourth embodiment. This is characterized in that the chuck claw tip 20 is fixed. Since the chuck claw body 10 and the chuck claw tip 20 have the same structure as that of the fourth embodiment, description thereof will be omitted. The adjustment spacer 70 has the same structure as that of the adjustment spacer used in the second embodiment shown in FIG.

  In the fifth embodiment, the adjustment spacer 70 is inserted in advance between the first wall surface 10A of the stepped portion 11 in the chuck claw body 10 and the wall surface 20A of the chuck claw tip 20 opposite thereto, as shown in FIG. After the screw bolt 30 as shown is inserted into the bolt insertion hole 22 of the chuck claw tip 20 through the through hole 70A of the adjustment spacer 70, the fixing bolt 50 is screwed into the bolt fixing hole 21, The side surface of the tip portion of the screw bolt 30 is tightened with the tip. In this state, since the chuck claw tip 20 is fixed to the screw bolt 30 by the fixing bolt 50, there is no fear of the adjustment spacer 70 dropping off, and the screw bolt 30 is screwed back. Thus, the wall surface 10 </ b> A of the chuck claw main body 10 and the wall surface 20 </ b> A of the chuck claw tip 20 contact the both surfaces of the adjustment spacer 70. Also in the fifth embodiment, the distance between the wall surface 10A of the stepped portion 11 and the wall surface 20A of the chuck claw tip 20 in the chuck claw body 10 is set to the thickness d of the adjustment spacer 70, and then the chuck claw tip 20 with the fixing bolt 50. It is not necessary to fix the chuck claw body 10 to the chuck claw body 10, so that the position of the rotation axis X can be adjusted more easily, and the position of the chuck claw tip 20 can be prevented from shifting in the horizontal direction and the front-back direction in the drawing by the action of the bolt insertion hole 22. Therefore, highly accurate position adjustment is possible. The thickness of the adjustment spacer 70 is various, and is determined by the set eccentricity amount, that is, the set eccentric width, and may be a stack of a plurality of spacers as described above.

  In addition, in order to prevent misalignment between the chuck claw main body 10 and the chuck claw tip 20 in the left / right and front / rear direction of the drawing, as shown in FIG. 11, in addition to those shown in FIGS. Any structure may be used. FIG. 11 is a view of the chuck claw 1 as viewed from the gripping surface A. The chuck claw body 10 extends in the direction of the rotation axis X on a surface that faces the chuck claw tip 20 and is perpendicular to the rotation axis X. An engagement groove 15 is provided. The chuck claw tip 20 is provided with an engagement protrusion 23 that fits into and engages with the engagement groove 15 of the chuck claw tip 20. The engagement groove 15 and the engagement protrusion 23 have a trapezoidal shape when viewed from the gripping surface A and are engaged with each other, and the respective surfaces are actually in light contact with each other. It is possible to move in the front-back direction of the drawing without being displaced in the left-right direction and the front-rear direction. With respect to this structure, in Embodiments 1 to 3 having the structures shown in FIGS. 5 to 8, the chuck claw tip 20 is fixed to the wall surface 10 </ b> B (FIG. 3) in the stepped portion 11 of the chuck claw body 10 with the fixing bolt 50. Therefore, since the chuck claw tip 20 does not move in the horizontal direction of the drawing, the chuck claw tip 20 may be provided with a projection that engages with the elongated hole 14, and there are various other structures. Conceivable. Of course, two or more chuck claws in the chuck mechanism may have the structure according to the present invention.

It is a figure which shows schematic structure of the chuck mechanism for lathes using the chuck nail | claw which concerns on this invention. It is a figure for demonstrating the eccentric range of the rotating shaft line X which passes along the rotation center of the workpiece | work processed by a lathe. It is a figure for demonstrating the structural member of the chuck nail | claw which concerns on embodiment of this invention. It is a figure which shows the side surface of the chuck nail | claw which concerns on Embodiment 1 of this invention. It is a figure which shows the partial cross section of the chuck nail | claw which concerns on Embodiment 1 of this invention. It is a figure which shows the partial cross section of the chuck nail | claw which concerns on Embodiment 2 of this invention. It is a figure which shows the partial cross section of the chuck nail | claw which concerns on Embodiment 3 of this invention. It is the figure which expanded the partial cross section of the chuck nail | claw which concerns on Embodiment 3 of this invention. It is a figure which shows the partial cross section of the chuck nail | claw which concerns on Embodiment 4 of this invention. It is a figure which shows the partial cross section of the chuck nail | claw which concerns on Embodiment 5 of this invention. It is a figure which shows an example of the structure for preventing the position shift in the chuck nail | claw which concerns on this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Chuck claw concerning the present invention in lathe chuck mechanism 2, 3 ... General chuck claw of lathe chuck mechanism 4 ... Chuck body 10 ... Chuck claw body 11 ... Chuck claw Stepped portion of the main body 10... Screwed hole for bolt of the chuck claw main body 10... Sliding groove of the chuck claw main body 10. Engaging groove 20... Chuck claw tip 21... Bolt fixing hole in chuck claw tip 20... 22 bolt insertion hole in chuck claw tip 20. Joint protrusion 30 ... Screw bolt 30A ... Male thread part 30B ... Screw bolt 30 tip surface 30C ... Small diameter part of screw bolt 30 40 ... For fixing Nut 50 ... fixed Bolt 60 ... gripping surface of the through hole A through C ... each chuck claws of the fixing nut 70 ... adjustment spacers 70A ... adjustment spacer 70

Claims (6)

At least one of the chuck claws in a lathe chuck mechanism including a plurality of chuck claws that grip or release the workpiece by moving in a direction perpendicular to the rotation axis of the workpiece to be lathe and reducing or expanding the diameter. A chuck claw comprising a chuck claw body portion and a chuck claw tip attached to a step portion having two orthogonal first and second wall surfaces formed on the chuck claw body portion,
A bolt screw hole that extends through the chuck claw main body portion perpendicularly to the rotation axis to the first wall surface of the stepped portion;
A long hole extending in the same direction as the rotation axis from the second wall surface of the step portion of the chuck claw body portion;
A bolt fixing hole extending from the chuck claw tip to the elongated hole in the same direction as the rotation axis;
The first screw of the stepped portion is screwed into the bolt screw hole, and the tip protrudes from the first wall surface of the stepped portion of the chuck claw main body and comes into contact with the tip of the chuck claw. A screw bolt for adjustment that adjusts the amount of the gap between the wall surface and the facing surface of the chuck claw tip facing the wall surface;
With the gap between the first wall surface of the stepped portion and the facing surface of the chuck claw tip portion held, the space between the bolt fixing hole and the elongated hole is tightened with a fixing bolt. A chuck claw for a lathe chuck mechanism, wherein the chuck claw tip portion is fixed to the second wall surface of the step portion in the chuck claw main body portion. A lathe chuck mechanism comprising a plurality of chuck claws for gripping or releasing the workpiece by moving in a direction perpendicular to the rotation axis of the workpiece to be lathe and reducing or expanding the diameter. In the chuck claw comprising at least one chuck claw main body portion and a chuck claw tip attached to a step portion having two orthogonal first and second wall surfaces formed on the chuck claw main body portion,
A bolt screw hole that extends through the chuck claw main body portion perpendicularly to the rotation axis to the first wall surface of the stepped portion;
A long hole extending in the same direction as the rotation axis from the second wall surface of the step portion of the chuck claw body portion;
A bolt fixing hole extending from the chuck claw tip to the elongated hole in the same direction as the rotation axis;
An adjustment spacer having a through hole and a thickness equal to the set eccentricity;
A screw bolt that is screwed into the screw screw hole and has a tip protruding from the first wall surface of the stepped portion of the chuck claw main body and extending into the through hole of the adjustment spacer;
The gap between the bolt fixing hole and the elongated hole is fixed in a state where the gap between the first wall surface of the stepped portion and the facing surface of the tip end portion of the chuck claw is held at the set eccentric amount. A chuck claw of a lathe chuck mechanism, wherein the chuck claw tip end portion is fixed to the second wall surface of the step portion of the chuck claw main body portion by tightening with a bolt. A lathe chuck mechanism comprising a plurality of chuck claws for gripping or releasing the workpiece by moving in a direction perpendicular to the rotation axis of the workpiece to be lathe and reducing or expanding the diameter. In the chuck claw comprising at least one chuck claw main body portion and a chuck claw tip attached to a step portion having two orthogonal first and second wall surfaces formed on the chuck claw main body portion,
A long hole extending in the same direction as the rotation axis from the second wall surface of the step portion of the chuck claw body portion;
A bolt fixing hole extending from the chuck claw tip to the elongated hole in the same direction as the rotation axis;
An adjustment spacer made of a magnetic material and having a thickness equal to the set eccentricity amount,
The gap between the bolt fixing hole and the elongated hole is fixed in a state where the gap between the first wall surface of the stepped portion and the facing surface of the tip end portion of the chuck claw is maintained at a preset eccentric amount. A chuck claw of a lathe chuck mechanism, wherein the chuck claw tip end portion is fixed to the second wall surface of the step portion of the chuck claw main body portion by tightening with a bolt. A lathe chuck mechanism comprising a plurality of chuck claws for gripping or releasing the workpiece by moving in a direction perpendicular to the rotation axis of the workpiece to be lathe and reducing or expanding the diameter. In the chuck claw comprising at least one chuck claw main body portion and a chuck claw tip attached to a step portion having two orthogonal first and second wall surfaces formed on the chuck claw main body portion,
A bolt screw hole that extends through the chuck claw main body portion perpendicularly to the rotation axis to the first wall surface of the stepped portion;
A long hole extending in the same direction as the rotation axis from the second wall surface of the step portion of the chuck claw body portion;
A bolt fixing hole extending from the chuck claw tip to the elongated hole in the same direction as the rotation axis;
An adjusting spacer having a thickness for adjusting a gap between the first wall surface of the stepped portion and a facing surface of the chuck claw tip portion facing the wall surface;
A screw bolt for adjustment which is screwed into the screw screw hole, and whose tip protrudes from the first wall surface of the stepped portion of the chuck claw main body and comes into contact with the adjustment spacer;
With the gap between the first wall surface of the stepped portion and the facing surface of the chuck claw tip portion held, the space between the bolt fixing hole and the elongated hole is tightened with a fixing bolt. A chuck claw for a lathe chuck mechanism, wherein the chuck claw tip end portion is fixed to the second wall surface of the step portion of the chuck claw body portion. A lathe chuck mechanism comprising a plurality of chuck claws for gripping or releasing the workpiece by moving in a direction perpendicular to the rotation axis of the workpiece to be lathe and reducing or expanding the diameter. In the chuck claw comprising at least one chuck claw main body portion and a chuck claw tip attached to a step portion having two orthogonal first and second wall surfaces formed on the chuck claw main body portion,
A bolt screw hole that extends through the chuck claw main body portion perpendicularly to the rotation axis to the first wall surface of the stepped portion;
A bolt fixing hole extending in the same direction as the rotation axis of the chuck claw tip,
A bolt insertion hole extending in a direction perpendicular to the rotation axis of the chuck claw tip and intersecting the fixing hole;
Screwed into the bolt screw hole, the tip portion protrudes from the first wall surface of the stepped portion in the chuck claw body portion and extends to the bolt insertion hole, and the first wall surface of the stepped portion and the stepped portion A screw bolt for adjustment that adjusts a gap between the opposing surface of the chuck claw tip portion facing the wall surface;
With the gap between the first wall surface of the stepped portion and the facing surface of the tip end portion of the chuck claw being held, the tip portion of the screw bolt is fixed by a fixing bolt from the bolt fixing hole. A chuck claw for a lathe chuck mechanism, wherein the chuck claw tip is fixed to the screw bolt. A lathe chuck mechanism comprising a plurality of chuck claws for gripping or releasing the workpiece by moving in a direction perpendicular to the rotation axis of the workpiece to be lathe and reducing or expanding the diameter. In the chuck claw comprising at least one chuck claw main body portion and a chuck claw tip attached to a step portion having two orthogonal first and second wall surfaces formed on the chuck claw main body portion,
A bolt screw hole that extends through the chuck claw main body portion perpendicularly to the rotation axis to the first wall surface of the stepped portion;
A bolt fixing hole extending in the same direction as the rotation axis of the chuck claw tip,
A bolt insertion hole extending in a direction perpendicular to the rotation axis of the chuck claw tip and intersecting the fixing hole;
An adjustment spacer having a through hole and a thickness equal to the set eccentricity;
The bolt is screwed into the bolt screw hole, and the tip portion protrudes from the first wall surface of the step portion in the chuck claw main body and is inserted into the bolt insertion hole through the through hole of the adjustment spacer. Threaded bolts,
In the state where the gap between the first wall surface of the stepped portion and the opposing surface of the tip end portion of the chuck claw is held at the set eccentricity amount, the screw bolt with a fixing bolt from the bolt fixing hole A chuck claw of a lathe chuck mechanism, wherein the chuck claw tip is fixed to the screw bolt.

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