JP2005186182A - Lathe - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To enhance work performance of adjusting the work piece gripping force of a collet chuck in a lathe to which the collet chuck is mounted. <P>SOLUTION: A draw bar 11, which is fitted and inserted to a main spindle 10 and driven to advance and retreat by a chuck cylinder, is connected to an expander 23, which is inserted to a collet 22 of an inner-diameter collet chuck 20, via adaptors 12, 13. A movable side stopper 13a is provided on the adaptor 13. A fixed side stopper 24 for clamping, with which the movable side stopper 13a is brought into contact and which regulates the movement of the adaptor 13 to the clamping side, and a fixed side stopper 25 for unclamping, which regulates the movement of the adaptor 13 to the unclamping side, are respectively screwed to a substrate 21. The fixed side stopper 24 for clamping and the fixed side stopper 25 for unclamping execute the axial positional adjustment of the main spindle 10 by executing rotation operation by an operating fixture 26, which is mounted to each fixture mounting hole 24a, 25a of the stoppers 24, 25. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a lathe configured to grip a workpiece by a collet chuck.

  A lathe may be equipped with a collet chuck as a chuck for mounting a workpiece on the spindle SP. For example, as shown in FIG. 8, the collet chuck has a base 51 having a tapered hole 51 a fixedly installed at the tip of the spindle SP, and a plurality of openable and closable claws inserted into the tapered hole 51 a of the base 51. The claw part 52a of the collet 52 has a tapered surface that can be fitted into the tapered hole 51a of the base 51.

  A draw bar DB having a collet 52 attached to the front end side is fitted in the main shaft SP so as to be able to advance and retreat in the axial direction of the main shaft SP, and the cylindrical shape of the chuck cylinder CS fixed to the rear end portion of the main shaft SP. The rear end portion of the draw bar DB that protrudes rearward from the main shaft SP is fixed to the piston rod PR.

  Accordingly, when the draw bar DB is advanced and retracted in the axial direction of the main shaft SP by the chuck cylinder CS, the collet 52 attached to the draw bar DB is advanced and retracted in the axial direction of the main shaft SP, and accordingly, the claw portion 52a of the collet 52 is moved. Then, it is pushed out to the large diameter side of the taper hole 51a of the base body 51, or is pulled into the small diameter side of the taper hole 51a of the base body 51. As a result, the claw portion 52a of the collet 52 opens and closes, and the workpiece can be unclamped or clamped.

  Further, an adjusting nut 53 connected to the piston rod PR of the chuck cylinder CS via a connecting member 54 is screwed to the rear end portion of the draw bar DB, and the shaft of the draw bar DB is rotated by rotating the adjusting nut 53. By advancing and retracting in the direction, it is possible to adjust the mounting position of the draw bar DB in the axial direction with respect to the piston rod PR of the chuck cylinder CS.

  Further, a fixed stopper 55 protruding rearward is attached to the cylinder body of the chuck cylinder CS, and the draw bar DB moves toward the tip side of the spindle SP by coming into contact with the fixed stopper 55. The movable side stopper 56 to be regulated is screwed to the piston rod PR of the chuck cylinder CS, and the draw bar DB is moved in the axial direction by rotating the movable side stopper 56 to advance and retract in the axial direction of the piston rod PR. The amount can be adjusted.

  Therefore, in a lathe equipped with such a collet chuck 50, the mounting position of the draw bar DB in the axial direction with respect to the piston rod PR of the chuck cylinder CS is adjusted according to the shape and size of the workpiece to be processed. By changing the retracting position of the claw portion 52a of the collet 52 with respect to the tapered hole 51a of the base body 51, the gripping force of the collet chuck 50 that grips the workpiece is adjusted, and the unclamping side of the draw bar DB (the tip of the spindle SP) The amount of protrusion of the collet 52 from the tapered hole 51a of the base 51 during unclamping is adjusted by adjusting the amount of movement to the side).

JP 2000-55012 A

  However, in the lathe as described above, when adjusting the gripping force of the workpiece by the collet chuck 50, the rear end of the spindle SP is actually gripped by the collet chuck 50 attached to the tip side of the spindle SP. By adjusting the position of the adjustment nut 53 provided on the side, the retracting position of the claw portion 52a of the collet 52 with respect to the tapered hole 51a of the base body 51 must be changed. . The same problem occurs when adjusting the amount of protrusion of the collet 52 from the tapered hole 51a of the base 51 during unclamping.

  Also, depending on the form of the lathe, there may be a case where it is not possible to secure an adjustment space such as the adjustment nut 53 and the movable stopper 56 as described above on the rear end side of the main spindle. In addition, there is a problem that a collet chuck that requires adjustment of the gripping force cannot be used.

  Accordingly, an object of the present invention is to improve the workability of adjusting the gripping force of the work by the collet chuck in a lathe equipped with a collet chuck.

  In order to solve the above-mentioned problems, the invention according to claim 1 is directed to a movable element constituting a collet chuck attached to the tip of the main shaft, directly or via an adapter on a draw bar inserted into the main shaft. In a lathe that is connected, and the collet chuck performs clamping and unclamping of the workpiece by moving the draw bar forward and backward in the axial direction of the main shaft, the connecting end side of the movable element in the draw bar Alternatively, the adapter is provided with a movable stopper, and when the collet chuck clamps the workpiece, the movable stopper is brought into contact with the fixed stopper for clamping to restrict the movement of the draw bar. A lathe is provided that can be adjusted in position.

  In particular, as in the lathe of the invention according to claim 2, when the collet chuck unclamps the workpiece, the unclamping fixed stopper for restricting movement of the draw bar by contacting the movable stopper is provided on the spindle. It is desirable that the position can be adjusted in the axial direction.

  In order to solve the above-mentioned problem, the invention according to claim 3 is characterized in that the movable element constituting the collet chuck attached to the tip of the main shaft is directly or directly attached to the draw bar inserted into the main shaft. In the lathe where the collet chuck clamps and unclamps the workpiece by moving the draw bar forward and backward in the axial direction of the main shaft, the movable element is connected to the main shaft. A lathe is connected to the draw bar or the adapter so as to be axially adjustable.

  Specifically, as in the lathe of the invention according to claim 4, the movable element is screwed into the adapter rotatably connected to the draw bar, and the adapter is rotated by an operation jig. You should be able to do that.

  As described above, in the lathe according to the first aspect of the present invention, the movable side stopper is provided on the connecting end side or the adapter of the movable element in the draw bar, and the movable side stopper abuts when the collet chuck clamps the workpiece. The clamp fixed-side stopper that restricts the movement of the draw bar is provided so that the position of the clamp can be adjusted in the axial direction of the main shaft. By appropriately changing the amount of movement of the element in the clamping direction, the gripping force of the workpiece by the collet chuck can be adjusted.

  Moreover, when adjusting the gripping force of the workpiece by the collet chuck, both the gripping of the workpiece and the position adjustment of the clamping fixed side stopper can be performed at the tip end side of the spindle, so that the workpiece is gripped at the tip end side of the spindle, The collet chuck adjustment workability is improved as compared with the conventional lathe in which the position adjustment of the draw bar with respect to the piston rod of the chuck cylinder (position adjustment of the adjustment nut 53 in FIG. 8) must be performed on the rear end side of the main shaft. Even with a lathe that cannot secure a space for adjusting the collet chuck on the rear end side of the spindle, a collet chuck that must adjust the gripping force for each workpiece may be mounted. It becomes possible.

  In the lathe according to the second aspect of the invention, when the collet chuck unclamps the workpiece, the movable-side stopper contacts the unclamped fixed-side stopper that regulates the movement of the draw bar, and the position is adjusted in the axial direction of the spindle. Therefore, by adjusting the position of the unclamping stationary stopper, the amount of movement of the movable element constituting the collet chuck in the unclamping direction can be minimized.

  In the lathe of the invention according to claim 3, the movable element constituting the collet chuck is connected to the draw bar or the adapter so that the position of the movable element can be adjusted in the axial direction of the main shaft. Of the movable element constituting the collet chuck by appropriately changing the axial relative position of the main shaft with respect to the draw bar or adapter of the movable element connected to the draw bar or adapter. By appropriately moving the stop position on the clamp side in the axial direction of the main shaft, the gripping force of the workpiece by the collet chuck can be adjusted.

  In addition, when adjusting the gripping force of the workpiece by the collet chuck, the workpiece is gripped and the position of the movable element constituting the collet chuck is adjusted on the tip side of the spindle, so that the workpiece is gripped on the tip side of the spindle. As a result, collet chuck adjustment workability is improved compared to conventional lathes where the adjustment of the position of the draw bar relative to the piston rod of the chuck cylinder (position adjustment of the adjustment nut 53 in FIG. 8) must be performed on the rear end side of the spindle. In addition, it is possible to mount a collet chuck that requires adjustment of the gripping force for each workpiece, even on a lathe that cannot secure a space for adjustment work on the rear end side of the spindle. become.

  In particular, in the lathe according to the fourth aspect of the invention, the position of the movable element is adjusted by rotating the adapter in which the movable element constituting the collet chuck is screwed. As in the case of adjusting the position of the movable element by rotating the side, normally it is not necessary to release the detent of the movable element that is detented each time, and the position of the movable element can be easily adjusted it can.

  Hereinafter, embodiments will be described with reference to the drawings. As shown in FIG. 1, this lathe has an inner diameter collet chuck 20 attached to the tip of the main shaft 10, and the inner diameter surface of the annular workpiece W can be gripped by the inner diameter collet chuck 20. ing.

  The inner diameter collet chuck 20 includes a cylindrical base 21 bolted to the front end surface of the main shaft 10, a cylindrical collet 22 having a plurality of gripping claws 22a formed by dividing the front end side in the circumferential direction, And an expander 23 that expands the gripping claws 22a of the collet 22 outward in the radial direction. The gripping claws 22a that are expanded outward in the radial direction by the expander 23 are formed on the inner peripheral surface of the annular workpiece W. It is designed to grip.

  The collet 22 has a base end portion that is not divided in the circumferential direction screwed to the distal end portion of the base body 21, and the inner peripheral surface of the distal end portion where the gripping claws 22 a are formed is large toward the distal end side. It has a tapered hole portion 22b formed to have a diameter.

  The expander 23 has a columnar straight portion 23 a and a tapered portion 23 b that fits into a tapered hole portion 22 b of the collet 22 that is connected to the distal end side of the straight portion 23 a. By pulling the inserted expander 23 toward the main shaft 10, the tapered portion 23b pushes the grip claw 22a of the collet 22 outward in the radial direction.

  A draw bar 11 attached to the rear end of the main shaft 10 and driven to advance and retreat in the axial direction of the main shaft 10 by a chuck cylinder (not shown) is fitted into the main shaft 10, and the draw bar 11 is connected via adapters 12 and 13. The expander 23 inserted in the collet 22 is connected. Therefore, when the draw bar 11 moves back and forth in the main shaft 10 in the axial direction, the expander 23 connected to the draw bar 11 also moves back and forth in the collet 22 in the axial direction of the main shaft 10.

  One adapter 13 having a collet 22 screwed in and out of the base 21 of the inner diameter collet chuck 20 in the axial direction of the main shaft 10 has a flange shape projecting radially outward at the center in the longitudinal direction. The movable side stopper 13a is provided, and the movable side stopper 13a comes into contact with the base 21 to restrict the movement of the adapter 13 (expander 23) to the clamp side (rear side). And the unclamped fixed side stopper 25 for restricting the movement of the adapter 13 (expander 23) to the unclamp side (front side) is screwed together.

  As shown in FIGS. 2 and 3, the clamp fixing side stopper 24 and the unclamping fixed side stopper 25 have a plurality of jig mounting holes 24a for detachably mounting an operation jig 26 for rotating operation. , 25a are formed at regular intervals in the circumferential direction, and the base 21 of the inner diameter collet chuck 20 is formed at the positions where the jig mounting holes 24a, 25a of the fixed side stopper 24 for clamping and the fixed side stopper 25 for unclamping are formed. An opening 21b that can be closed by the lid member 21a is formed in the corresponding part.

  Accordingly, the lid member 21a is removed, and the operation jig 26 is mounted in the jig mounting holes 24a and 25a from the opening 21b of the base body 21, and the clamp fixing side stopper 24 and the unclamp fixing are secured by the operation jig 26. When the side stopper 25 is rotated, the clamping fixed side stopper 24 and the unclamping fixed side stopper 25 move in the axial direction of the main shaft 10, and the amount of movement of the adapter 13 (expander 23) to the clamping side (rear side) Since the amount of movement to the unclamping side (front side) can be changed, the amount of movement of the adapter 13 (expander 23) to the clamping side (rear side) can be changed as appropriate so that the inner diameter collet chuck 20 The gripping force of the workpiece W can be adjusted, and the amount of movement of the adapter 13 (expander 23) to the unclamping side (front side) can be adjusted appropriately. By changing, it is possible to suppress the amount of protrusion of the base body 21 of the expander 23 at the time of unclamping to a minimum.

  As described above, in this lathe, when the gripping force of the workpiece W by the inner diameter collet chuck 20 is adjusted, both the gripping of the workpiece W and the position adjustment of the clamping fixed side stopper 24 and the unclamping fixed side stopper 25 are performed on the spindle. 10 to adjust the position of the draw bar relative to the piston rod and the stroke of the draw bar while actually holding the work with the collet chuck on the tip side of the spindle. Compared with a conventional lathe where position adjustment must be performed on the rear end side of the main shaft, the adjustment workability of the inner diameter collet chuck 20 is improved.

  In the above-described embodiment, not only the clamping fixed side stopper 24 for adjusting the gripping force of the workpiece W by the inner diameter collet chuck 20 but also the amount of protrusion of the expander 23 from the base 21 during unclamping is adjusted. However, the present invention is not limited to this, and at least a clamp fixed-side stopper for adjusting the gripping force of the workpiece W by the inner diameter collet chuck 20 is provided. The unclamping fixed stopper 25 may be omitted.

  In the above-described embodiment, the expander 23, which is a movable element of the inner diameter collet chuck 20, is connected to the draw bar 11 via the adapters 12 and 13. However, the present invention is not limited to this. It is also possible to connect the expander directly to the draw bar. In this case, it is needless to say that the movable side stopper needs to be provided on the draw bar.

  4 to 6 show other embodiments. As shown in FIG. 4, the lathe has an outer diameter collet chuck 30 attached to the tip of the main shaft 10, and the outer diameter collet chuck 30 can grip the outer peripheral surface of the workpiece. .

  The outer diameter collet chuck 30 includes a cylindrical base 31 bolted to the front end surface of the main shaft 10, and a cylindrical collet 32 having a plurality of gripping claws 32 a formed by dividing the front end side in the circumferential direction. The tip of the base 31 has a tapered hole 31a formed so that the inner peripheral surface has a larger diameter toward the tip, and the collet 32 has a gripping claw 32a. It is formed in a taper shape that fits into the taper hole 31 a of the base 31.

  Accordingly, when the collet 32 introduced into the base body 31 is pulled to the main shaft 10 side, the gripping claws 32a are compressed inward in the radial direction by the tapered hole portions 31a of the base body 31. The outer peripheral surface of the workpiece is gripped.

  A draw bar 11 attached to the rear end of the main shaft 10 and driven to advance and retreat in the axial direction of the main shaft 10 by a chuck cylinder (not shown) is fitted into the main shaft 10, and the draw bar 11 is connected via adapters 14 and 15. It is connected to a collet 32 inserted into the base 31. Therefore, when the draw bar 11 advances and retreats in the main shaft 10 in the axial direction, the collet 32 connected to the draw bar 11 also advances and retreats in the base 31 in the axial direction of the main shaft 10.

  The rear end portion of the adapter 14 is screwed to the front end portion of the draw bar 11, and the adapter 15 accommodated from the front end portion of the main shaft 10 to the base body 31 is rotatably connected to the front end portion of the adapter 14. . The collet 32 introduced into the base 31 is inserted into the adapter 15, and a base end portion that is not divided in the circumferential direction is screwed into a female screw portion formed on the inner peripheral surface of the adapter 15. The collet 32 is prevented from rotating by a recess 32 b formed in one gripping claw 32 a engaging with a rotation-preventing member 33 attached to the tip of the base 31.

  As shown in FIGS. 5 and 6, one adapter 15, which is advanced and retracted in the base 31 of the outer diameter collet chuck 30 in the axial direction of the main shaft 10 and screwed with the collet 32, has a central portion in the longitudinal direction. In addition, a plurality of jig mounting holes 15 a for detachably mounting the operation jig 34 for rotating operation are formed at regular intervals in the circumferential direction, and the adapter 15 is provided in the base 31 of the outer diameter collet chuck 30. An opening 31c that can be closed by a lid member 31b is formed at a portion corresponding to the formation position of the jig mounting hole 15a.

  Accordingly, when the lid member 31b is removed and the operation jig 34 is mounted in the jig mounting hole 15a from the opening 31c of the base 31, and the adapter 15 is rotated by the operation jig 34, the rotation is prevented. Since the collet 32 screwed to the adapter 15 moves in the axial direction of the main shaft 10, the gripping force of the workpiece by the outer diameter collet chuck 30 can be changed by appropriately changing the stop position of the collet 32 on the clamp side (retraction side). Adjustments can be made.

  As described above, in this lathe, when the gripping force of the workpiece by the outer diameter collet chuck 30 is adjusted, both the gripping of the workpiece and the position adjustment of the adapter 15 can be performed on the distal end side of the main shaft 10. As in the case of the lathe shown in FIG. 3, the workability of adjusting the outer diameter collet chuck 30 is improved as compared with the conventional lathe.

  In the above-described embodiment, the collet 32, which is a movable element of the outer diameter collet chuck 30, is connected to the draw bar 11 via the adapters 14 and 15. However, the present invention is not limited to this. It is also possible to connect the collet directly to the draw bar. In this case, the collet is screwed into the draw bar. Therefore, in order to adjust the collet position, the collet itself must be rotated. Therefore, when the collet is directly connected to the draw bar, it is necessary to provide a rotation preventing mechanism that can hold the rotated collet at an arbitrary position.

  In the above-described embodiment, the lathe on which the outer diameter collet chuck 30 in which the collet 32 advances and retreats in the axial direction of the main shaft 10 has been described. However, the present invention is not limited to this, and for example, the collet is fixed. Thus, the base body side having the tapered hole portion may be advanced and retracted in the axial direction of the main shaft 10. In that case, needless to say, the base body, which is a movable element of the collet chuck, must be connected to a draw bar or an adapter so that the position of the base body can be adjusted in the axial direction of the main shaft.

  Further, in each of the embodiments described above, in order to adjust the gripping force of the workpiece, the lathe equipped with the inner diameter collet chuck 20 is clamped (rear side) of the expander 23 that is a movable element of the inner diameter collet chuck 20. For a lathe equipped with an outer diameter collet chuck 30 mounted on the lathe, the mounting position of the collet 32, which is a movable element of the outer diameter collet chuck 30, with respect to the adapter 15 is adjusted. Although the configuration is adopted, the present invention is not limited to these configurations. For a lathe equipped with an inner diameter collet chuck, a configuration that adjusts the mounting position of the expander, which is a movable element, with respect to the adapter or draw bar can be adopted. For lathes equipped with an outer diameter collet chuck, the clamp side of the collet, which is a movable element (rear) ) It is also possible to adopt a configuration for adjusting the amount of movement.

  For example, as shown in FIG. 7, for a lathe equipped with an inner diameter collet chuck 20A, an expander 23A, which is a movable element, is connected to a draw bar (not shown) via an adapter 12 instead of providing a fixed stopper. By being screwed into the adapter 13A, the position is adjusted in the axial direction of the main shaft 10 so as to be adjustable. In this case, the position of the expander 23A in the axial direction of the main shaft 10 is adjusted by rotating the expander 23A from the front side using a jig or the like. In order to keep the expander 23A in the adjusted state, A screw hole penetrating in the longitudinal direction is formed in the center of the expander 23A, a bolt 24A is screwed into the screw hole, and a screw hole formed in the adapter 13A at the tip of the bolt 24A is screwed into the expander 23A. The expander 23A that is screwed into the adapter 13A is stretched by pressing so that the expander 23A is prevented from rotating with respect to the adapter 13A.

It is a fragmentary sectional view showing one embodiment of a lathe concerning this invention. It is sectional drawing which shows the adjustment operation state of the holding | grip force of the internal diameter collet chuck mounted in the same lathe. It is sectional drawing along the XX line of FIG. It is a fragmentary sectional view which shows the lathe which is other embodiment. It is sectional drawing which shows the adjustment operation state of the holding | grip force of the outer diameter collet chuck mounted in the lathe same as the above. FIG. 6 is a cross-sectional view taken along line YY in FIG. 5. It is a fragmentary sectional view which shows the lathe which is other embodiment. It is a fragmentary sectional view which shows the conventional lathe.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Main shaft 11 Draw bar 12, 13, 13A, 14, 15 Adapter 13a Movable stopper 15a Jig mounting hole 20, 20A Inner diameter collet chuck 21, 21A Base body 21a Lid member 21b Opening 22, 22A Collet 22a Grip claw 22b Taper hole 23 , 23A Expander (movable element)
23b Taper part 24 Clamping fixed stopper 24a, 25a Jig mounting hole 24A Bolt 25 Unclamping fixed stopper 26 Operation jig 30 Outer diameter collet chuck 31 Base 31a Taper hole part 31b Lid member 31c Opening 32 Collet (movable) element)
32a Grip claw 32b Recess 33 Detent member 34 Operation jig

Claims (4)

A movable element constituting a collet chuck attached to the tip of the main shaft is connected directly or via an adapter to a draw bar inserted into the main shaft,
In the lathe where the collet chuck performs workpiece clamping and unclamping by moving the draw bar forward and backward in the axial direction of the main shaft,
A movable side stopper is provided on the connecting end side of the movable element in the draw bar or the adapter,
When the collet chuck clamps the workpiece, a clamp-side stopper for clamping that restricts the movement of the draw bar by contacting the movable-side stopper is provided so that the position of the clamp can be adjusted in the axial direction of the spindle. Turning lathe.   When the collet chuck unclamps the workpiece, an unclamping fixed stopper for restricting the movement of the draw bar by contacting the movable stopper is provided so as to be adjustable in position in the axial direction of the spindle. The lathe according to 1. A movable element constituting a collet chuck attached to the tip of the main shaft is connected directly or via an adapter to a draw bar inserted into the main shaft,
In the lathe where the collet chuck performs workpiece clamping and unclamping by moving the draw bar forward and backward in the axial direction of the main shaft,
A lathe, wherein the movable element is connected to the draw bar or the adapter so that the position of the movable element can be adjusted in the axial direction of the main shaft. The movable element is screwed into the adapter rotatably connected to the draw bar;
The lathe according to claim 3, wherein the adapter can be rotated by an operation jig.

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