JP2003145304A - Longitudinal positioning device for work - Google Patents

Abstract

(57) [Summary] (with correction) [PROBLEMS] To provide a longitudinal positioning device in which an adjusting member for longitudinal positioning of a work does not rotate during work processing. A guide sleeve (12) having a common axis with a spindle (2) and a female screw threaded at a tip of a cylindrical portion and fixed to a headstock (1). An adjusting shaft 15 provided with a guide groove along the axial direction of the outer periphery of the end and a male screw screwed with the female screw are screwed, and are guided so as to rotate integrally with the adjusting shaft 15 and move only in the axial direction. A stopper shaft 13 which moves forward and backward in the main shaft 2 with the rotation of the adjusting shaft 15 and a stopper shaft 1
There is provided a stopper shaft 13 which is rotatably supported by bearing the workpiece 3 in the main shaft 2 and abuts on the workpiece W, and a driving member for driving the adjusting shaft 15.

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a spindle work in which a workpiece is inserted into a spindle hole of a machine tool from a chuck side and a portion to be processed is projected from the chuck. When grasped,
The present invention relates to a longitudinal positioning device that performs longitudinal positioning of a shaft workpiece. 2. Description of the Related Art FIG. 3 shows a conventional longitudinal positioning device for a work used in a lathe. In FIG. 3, a conventional work longitudinal positioning device includes a rotary cylinder 10 for opening and closing a claw of a hydraulic chuck 103 at a rear end of a spindle 102 supported by a plurality of bearings (not shown) provided on a headstock 101.
4, the adjusting nut 109 is concentrically attached thereto, and has a stopper shaft 106 for screwing the adjusting nut 109 with the adjusting nut 109. The lock nut 105 for restricting the relative movement between the adjusting nut 109 and the stopper shaft 106 is connected to the stopper shaft 106. Adjustment nut 10
5 and a draw pipe 10 in the center hole of the main shaft 102.
7 so that the position in the axial direction can be adjusted. A stopper 108 is provided at the tip of the stopper shaft 106, and the work is positioned by a work contact surface 108a. A rotary joint 110 for supplying air or coolant to the cutting portion through the center hole of the stopper shaft 106 is provided.
Is connected to the rear end. The position of the abutment is adjusted each time the lot of the workpiece changes. By changing the axial position of the nut 109 and the stopper shaft, the adjustment range can be set to L100 and the axial positioning of multiple types of workpieces W of different lengths can be supported. The work W
And a cutting process of a portion protruding from the chuck is performed. [0003] As described in the prior art, according to the longitudinal positioning device employed so far, a portion projecting from the rear portion of the cylinder during the machining of a work (the projecting amount L200 in FIG. 3). ), The stopper shaft extending rearward from the lock nut 105 and connected to the rotary joint 110 protrudes and rotates. However, there is a problem that the width of the adjustment range L100 of the work longitudinal position is narrow because the protrusion amount L200 cannot be increased due to the limitation based on the critical rotation speed. Also, in order to increase the adjustment range L100, it is necessary to replace the stopper shaft or the tip of the stopper with the contact each time. Further, since the stopper position is manually adjusted, a master is attached to the hydraulic chuck at the time of adjustment. In addition, there is a problem that the longitudinal position (fixed-size position) must be determined using a gauge or the like, and it takes time to change the setup. Accordingly, the present invention has been made in view of the above-mentioned problems of the prior art, and an object of the present invention is to rotate the work longitudinal positioning adjustment member during processing of the work so as not to rotate. A work longitudinal positioning device that eliminates the protrusion of the stopper shaft from the rear of the cylinder so as not to be restricted by the rotational speed, expands the adjustment range in the longitudinal direction, and can automatically perform longitudinal positioning of the work. It is what we are going to offer. [0005] In order to achieve the above object, an invention according to claim 1 is a device for longitudinally positioning a work in a spindle of a machine tool, which is fixed to a headstock. A guide sleeve having a female thread portion concentric with the main shaft at the tip, an adjusting shaft provided inside the guide sleeve and having one end supported rotatably only, and a male thread portion screwed with the female thread portion; A stopper shaft movably provided only in the axial direction with respect to the adjustment shaft, the stopper shaft being advanced and retracted by the male screw portion and the female screw portion within the main shaft with the rotation of the adjustment shaft, and a work provided at the tip of the stopper shaft. And a driving member for driving the adjusting shaft, the member for adjusting the longitudinal positioning amount of the work does not rotate during the work of the work. According to a first aspect of the present invention, an adjustment member relating to positioning of a work in a longitudinal direction within a main shaft is prevented from rotating during processing of the work. A member related to the positioning in the longitudinal direction is a stopper shaft which is supported at the rear end of the stopper which rotates in contact with the workpiece and which is largely inserted in the main shaft hole, an adjustment shaft which rotates synchronously with the stopper shaft, an adjustment shaft And a drive member such as a motor for rotating and driving a feed guide sleeve and an adjustment shaft by using a screw to advance and retreat in the axial direction, all of which are fixed to the headstock. Therefore, there is no rotating member provided on the spindle axis and protruding backward from the rotary cylinder for driving the opening and closing of the chuck, and only the stopper that rotates in contact with the workpiece in the spindle is rotated.
It is possible to avoid the limitation of the critical speed due to the high-speed rotation of the protrusion at the rear end of the main shaft. Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a sectional explanatory view of a work longitudinal positioning device according to the present invention, and FIG. 2 is an enlarged explanatory view of a main part of FIG. In FIG. 1, a spindle 2 is mounted on a headstock 1 of a lathe by a plurality of bearings (not shown), and a hydraulic chuck 3 is concentrically fixed to a tip of the spindle 2. A rotary cylinder 5 for opening and closing the claw of the hydraulic chuck 3 is attached to the rear end of the main shaft 2 via a flange 4. The draw pipe 7 connecting the piston 6 of the rotary cylinder 5 and the chuck 3 is composed of a main shaft 2
Is movably inserted in the center hole 2a. The main part of the apparatus for positioning the workpiece W in the longitudinal direction according to the present invention is partially inserted into the draw pipe 7 and its tip is supported by a stopper 14 which comes into contact with the workpiece W, and moves forward and backward integrally therewith. It comprises a stopper shaft 13, an adjustment shaft 15 rotatably supported on a guide sleeve 12 fixedly mounted on the headstock 1, and a motor 11 of driving means. In FIG. 2, a headstock 1 is mounted on a rear axis of the main shaft, and a guide sleeve 12 and
An adjustment shaft 15 and a stopper shaft 13 are provided, and neither of them rotates during the work processing. One end of the adjustment shaft 15 is inserted into a guide sleeve 12 fixed to the headstock 1 and rotatably supported. That is, the guide sleeve 1
The shaft is supported by a hole 12b formed at the rear end of the guide sleeve 12, one flange surface 15a abuts on the end surface 12a of the hole, and is further formed at the rear end hole of the guide sleeve 12, and is screwed with the screw 12c. An end face of the round nut 8 having a small screw for locking and having a thread formed in a diameter is in contact with the other flange end face 15f so that a gap is adjusted and the end face is rotatably provided. The adjustment shaft 15 rotates from the output shaft of the motor 11 attached to the support frame 10 to a dimming pulley 18 attached to the shaft end of the adjustment shaft 15 via a conductive member such as a timing pulley 16 and a timing belt 17. It is transmitted and driven forward and backward. On the other end side (the chuck 3 side of the main shaft 2) of the adjusting shaft 15 following the flange surface 15a, a stepped small-diameter shaft portion 15e is formed following the shaft portion radially supported by a predetermined width. . The length of the small-diameter shaft portion 15e is determined by the adjustment amount L in the work longitudinal direction.
The above-described guide groove 15c is formed substantially all over the length. The front end surface 12e of the guide sleeve 12 is located at a position slightly extended from the front end surface 15d of the small diameter shaft portion of the adjustment shaft 15. An axially slidable gap is provided in the outer diameter of the small-diameter shaft portion 15e, and a cylindrical stopper shaft 13 is fitted. The outer diameter of the cylindrical portion 15e is set to a screw 13a in association with the adjustment of the longitudinal position of the work. Is provided. An external thread 13a of a stopper shaft 13 is inserted into a screw 12d to be threaded at a front end of the guide sleeve 12 for a predetermined length. Adjusting shaft 15 and stopper shaft 13
The guide groove 15c of the small diameter shaft portion 15e is rotated
A key member 19 slidable in the longitudinal direction of the groove and fixed to the rear end of the stopper shaft 13 is engaged. The key member 19 rotates the stopper shaft 13 in synchronization with the rotation of the adjustment shaft 15, and the stopper shaft 13 moves forward and backward.
Can be positioned in the longitudinal direction. The range of the screw 13a is designed so that the key member 19 can move over the entire range of the longitudinal dimension of the guide groove 15c. Referring to FIG. 1, a cylindrical stopper shaft 13 having a length substantially in the middle of the draw pipe 7 has a front end portion inserted into a main shaft hole, and a rear end side fitted into a small-diameter shaft portion of an adjustment shaft 15. ing. For this reason, the front end portion of the stopper shaft 13 is cantilevered, and it is necessary to support the stopper shaft 13 at the inner diameter portion of the draw pipe 7 that rotates integrally with the main shaft 2. The stopper 14 which is inserted with a gap provided in the inner diameter of the draw pipe 7 so as to be slidable in the axial direction has a front end face made of a metal plate 20 made of a material capable of contacting the work W, and has a cylindrical shape. A small-diameter shaft 21 is provided at the front end of the stopper shaft 13, and the center of the stopper 14 that rotates while contacting the workpiece is supported via bearings 22 and 23. Since the stopper 14 rotates integrally with the draw pipe 7, a groove 14a is engraved on the outer periphery of the stopper 14, an O-ring 24 is fitted therein, and frictional resistance is given to rotate the stopper 14 so as to rotate. The O-ring 24 is also provided to prevent coolant from leaking. The headstock 1 is inserted through the center hole of the stopper shaft 13.
The air or the coolant supplied to the work W from the rear passes through the center hole of the fixed-size stopper 14 rotating from the fixed small-diameter shaft 21. Air or coolant is applied to the bearing 22,
A check valve 25 is pressurized by a spring 26 so as not to flow back to 23 and is brought into contact with the end face of the small diameter shaft 21. Next, the operation of the longitudinal positioning device of the present invention will be described. 1 and 2, the pulley 16, the belt 17, and the pulley 1 are rotated by rotating the motor 11.
8, the adjusting shaft 15 and the stopper shaft 13 engaged with the adjusting shaft 15 by the key member 19 are synchronously rotated. The external thread 13 a of the outer periphery of the stopper shaft 13 is screwed with an internal thread 12 d of a guide sleeve 12 fixed to a support frame 10 provided behind the headstock 1. The stopper shaft 13 rotates and can move forward and backward together with the key member 19 along a groove 15c formed in the longitudinal direction of the outer periphery of the adjustment shaft 15 in the direction of the chuck 3. The longitudinal direction of the stopper shaft 13 is fixed and positioned by the brake function of the motor 11 in the draw pipe 7 which rotates integrally with the main shaft 2 by numerical control of the rotation of the motor 11. The small-diameter shaft 21 fixed to the front end of the stopper shaft 13 supports a stopper 14 that rotates integrally with the main shaft via bearings 22 and 23. Therefore, even if the stopper shaft 13 is stationary, there is no contact with the inner diameter of the draw pipe 7. The stopper 14 has a gap enough to be movable.
No vibration is generated because the O-ring 22 is fitted in the draw pipe 7 with the O-ring 22 attached to the groove provided in the outer shape of No. 4. Further, the O-ring 22 rotates integrally with the draw pipe 7 due to frictional resistance generated between the O-ring 22 and the outer periphery. A wear-resistant paddle 20 is fixed between the stopper 14 and the work W, but can be replaced at a predetermined number of rotations. Since the longitudinal positioning device of the present invention operates as described above, it has the following three functional features. First, when adjusting the work longitudinal position, the position of the stopper shaft 13 can be accurately detected based on the output of the rotation detector of the motor 11, and an arbitrary position can be easily set within the range of the adjustment shaft. Second, by registering the longitudinal position of the work W in advance and confirming the longitudinal position while grasping the work, the work can be determined and the machining program can be automatically selected. If the motor 11 becomes overtorqued for some reason during positioning, it can be avoided by using a torque skip function that is a torque management function of the motor 11. Third
In addition, since the amount of protrusion of the member relating to the longitudinal positioning device from the rotary cylinder 5 to the rear is constant regardless of the longitudinal position of the stopper support shaft, the limitation by the rotational speed is suppressed, and a wide adjustment range of the longitudinal position of the work can be obtained. The longitudinal positioning device for a workpiece according to the present invention is constructed as described above and has the following effects. A remarkable effect of the present invention is that the member including the stopper shaft related to the longitudinal positioning of the work does not rotate during the work of the work except for the stopper which comes into contact with the work. Accordingly, the following effects can be obtained. Since the stopper shaft for positioning the work in the main shaft hole is driven by the control motor via the adjustment shaft, the work longitudinal positioning is accurate. In addition, positioning data can be input in advance, and automatic setting of works having different lengths is easy. Further, since the amount of protrusion to the rear of the rotary cylinder for driving the chuck is constant and does not rotate during work processing, there is no need to limit the rotational speed of the spindle. Also, since there is no need to manually move the stopper shaft back and forth for adjustment, there is an effect that the work efficiency is improved without requiring a setup change time when changing the longitudinal dimension of the work.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an explanatory view of a work longitudinal positioning device according to the present invention. FIG. 2 is an enlarged view of a main part of FIG. FIG. 3 is an explanatory view of a conventional work longitudinal positioning device. [Description of Signs] 1 Headstock 2 Spindle 3 Hydraulic chuck 4 Flange 5 Rotary cylinder 6 Piston 7 Draw pipe 8 Split nut 10 Support frame 11 Motor 12 Guide sleeve 13 Stopper support shaft 14 Stopper 15 Adjustment shaft 16 Timing pulley 17 Timing belt 18 Timing pulley 19 Key member 20 Detent 21 Small diameter shaft 22, 23 Bearing 24 O-ring 25 Valve 26 Spring W Work

Claims (1)

Claims: 1. A longitudinal positioning device for a work in a main spindle of a machine tool, comprising: a guide sleeve fixed to a headstock and having a female thread portion concentric with the main spindle at a tip end; An adjusting shaft provided inside and supported at one end only to be rotatable, and having a male thread portion screwed with the female thread portion, provided so as to be movable only in the axial direction with respect to the adjusting shaft, and adapted to rotate the adjusting shaft. Accordingly, a stopper shaft which is moved forward and backward by the male screw portion and the female screw portion within the main shaft, a stopper provided at the tip of the stopper shaft and abutting on a workpiece and rotating integrally therewith, and a drive for driving the adjusting shaft A member for adjusting the longitudinal positioning amount of the workpiece during processing of the workpiece, wherein the member does not rotate.