JPH0574705U - Center with heart adjustment mechanism - Google Patents

Abstract

(57) [Abstract] [Purpose] A compact attachment is detachably attached to a standard tailstock to enable highly accurate taper correction. An eccentricity is formed in a center hole 12b of a case 12 having a taper shank portion 12a that is detachably fitted in a taper hole 11a of a tailstock shaft 11 with a slight eccentricity amount of about 0.1 mm. Spindle 1 with taper hole 13a
3 is rotatably supported, and a shifter fork 15a of a shifter shaft 15 provided on a case so as to be movable in a direction perpendicular to a frame body 17 is engaged with a lever 14 fixed to a spindle and screwed to the shifter shaft. The spindle is rotated by manually rotating the feed screw with a fine adjustment grip, and the taper adjustment is performed by changing the angular position of the maximum eccentric point of the center 22 with respect to the spindle.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a center having a center center adjusting mechanism for a machine tool, such as a grinding machine, which must accurately adjust the cylindricity of a workpiece during machining.

[0002]

[Prior Art]

 Conventionally, in a cylindrical grinder that grinds while supporting the work at both centers, if the work being supported is not parallel to the longitudinal feed direction, the work will taper and the cylindricity will change. In order to correct and adjust this, it takes skill and time to rotate a heavy table and adjust the taper on the order of a few microns. Therefore, various methods have been considered, but as a method using eccentricity, there is JP-B-59-20884. As shown in FIGS. 6 and 7, the piston rod 102 of the fluid pressure cylinder provided outside the tailstock main body 101 pivots the cam shaft 103 to finely move the cam rod 104 to form a cylindrical shape of the cam rod. A lever 107 having a small shaft 106 penetrating the head portion 105 and slidable in parallel with the tailstock sleeve shaft 108 is connected to the sleeve shaft 108, and rotation of the lever 107 rotates the sleeve shaft 108 and the center 109. In addition to moving the sleeve, it can be moved forward and backward together with the sleeve, and a hydraulic circuit that operates the spindle is provided for manual adjustment, and the adjustment amount can be read on the scale plate through the magnifying mechanism. It was done like this.

Alternatively, another method using eccentricity is JP-B-61-85302. As shown in FIG. 8, a center 111 having an eccentricity between the shaft center of the taper portion supporting the workpiece and the shaft center of the cylindrical handle portion is inserted into the eccentric sleeve 112 by the cylindrical handle portion as shown in FIG. The eccentric sleeve is inserted into the taper hole of the case 113 integrated with the tailstock body, and the eccentric sleeve is pressed by the spring 114 toward the end portion having a smaller outer diameter.

[0004]

[Problems to be Solved by the Invention] In the former case described in the related art, the tailstock itself is special and large and the cost is high, and it is difficult to add it to the existing machine afterwards, and it is common to other machines. It has a problem that it cannot be used, and the latter has a problem that it is not suitable for a grinder that frequently adjusts. The present invention has been made in view of the above problems of the conventional technology, and its purpose is to provide a simple tailstock that can be mounted as an attachment on a standard tailstock and can perform highly accurate taper correction. It aims to provide a center with a heart adjustment mechanism.

[0005]

[Means for Solving the Problems]

 To achieve the above object, a center with a centering mechanism according to the present invention comprises a case having a taper shank portion detachably mounted on a tailstock shaft, and a rotary shaft rotatably supported in a center hole of the case. A spindle having a tapered hole that is eccentric to the center, a center that is detachably fitted in the eccentric tapered hole, a lever that is fixed to the spindle at a right angle, and a case that is perpendicular to the axis of the case. It includes a shifter shaft that is movably provided and has a shifter fork that engages with the tip of the lever, and a feed screw that moves the shifter shaft, and pivots a center that is eccentric about the center line of the tailstock shaft. Then, the taper is corrected.

[0006]

[Action]

 First, the rotation angle of the spindle with respect to the case is adjusted so that the eccentric position of the center comes to the upper side or the lower side in the vertical direction, and in this state, the workpiece is supported on both centers and the cylindrical portion is trial ground. Then, the outer diameters of both ends of the cylindrical portion are measured to find the difference, and the spindle is rotated to change the rotation angle of the spindle with respect to the case so that the center of the center moves on the horizontal plane by half the difference. Adjust the taper.

[0007]

【Example】

 Examples will be described with reference to FIGS. 1 to 5. In a cylindrical grinder, a table lower table (not shown) is movably placed on a sliding surface in the Z-axis direction cut on the front side of a bed 1, and a table 2 is placed on the table lower table in a horizontal plane and a central axis of rotation 3 It is provided so that it can turn around. A headstock 4 is mounted on the left side of the table 2 so as to be movable in position, a center 5 is fitted to the tip of the main spindle fixed to the headstock 4, and a disc rotatably supported on the outer periphery of the tip of the main spindle 5. A drive pin 7 is planted on the end face of 6. Further, a tailstock 8 is mounted on the right side of the table 2 so as to be movable in position, and a tailstock shaft 11 is fitted in a concentric hole 9a with a main shaft of a tailstock body 9 so as to be axially movable. A case 12 integrally having a tapered shank portion 12a is detachably fitted in the tapered hole 11a at the end.

The case 12 has a central blind hole 12b bored from the front end side, and the spindle 13 is rotatably supported in the blind hole by a plurality of bearings. An eccentric taper hole 13a having a slight eccentricity a (about 0.1 mm) with respect to the center of rotation is bored at the tip of the spindle 13. Further, a lever 14 is fixed to the center of the spindle 13 at a right angle to the axis, and a shifter fork 15a that engages with the lever 14 is inserted into a hole formed in a frame 17 fixed to the case 12 at a right angle. A shifter shaft 15 integrally having a screw is inserted so as to be movable in the axial direction, and the feed screw 10 supported by the frame body so as to be rotatable only is screwed into the screw because it is engraved at the tip of the shifter shaft 15 concentrically. . A fine adjustment grip 16 having a scale ring 16a is integrally fitted to the tip of the feed screw 10, a backlash removing spring 28 for the feed screw 10 is provided in the frame body 17, and the corresponding position of the frame body 17 is provided. A plate 18 having a pointer wire for the scale ring 16a is attached to the.

A front lid 19 is fixed to the tip of the case 13, a scale plate 21 representing the maximum eccentric position is fixed to the tip of the front lid 19, and a tip of the spindle 13 is provided to facilitate the return to the origin. A disc 20 having a pointer line is fixed. A center 22 is fitted into an eccentric taper hole 13a of the spindle 13, a round nut 29 at the right end of the spindle 13 is provided with a tightening adjustment hole 12c on the outer periphery of the case 12, and a blind lid 27 is attached to the hole 12c. ing. On the other hand, a guide base (not shown) having a guide in the X-axis direction is fixed on the rear side of the bed 1, a grindstone base 23 is movably mounted on the guide base, and the grindstone shaft is rotatably instructed to the grindstone base 23. A grindstone 25 is fitted on the left side of 24.

Next, the operation of this embodiment will be described. First, the spindle 13 is swung by the fine adjustment grip 16 and set so that the pointer line of the disc 20 fixed at the tip points to the zero position on the vertical line of the scale plate 21, and then the work is performed between the centers 5 and 22. The cylinder W is roughly ground while supporting the object W, and the outer diameters of both ends are measured to determine the dimensional difference and the taper direction. Then, for example, when the outer diameter of the tailstock side is larger by 0.05 mm, as shown in FIG. 5, the stylus of the dial gauge 26 whose fulcrum is on the case 12 or the table 2 is placed on the outer circumference of the straight portion of the center 22. To the front in the horizontal direction and read the value of the pointer at this time.

Next, the fine adjustment grip 16 is turned to rotate the spindle 13 counterclockwise in FIG. Then, the rotation of the spindle 13 is stopped at the position where the pointer moves 0.025 (mm) in the negative direction on the scale of the dial gauge 26 from the value read previously. Then, the cylindrical surface is roughly ground again to check for taper, and if it is within the allowable tolerance, finish grinding is started. The center with a center adjusting mechanism of the present invention is not limited to manual taper adjustment. Instead of the fine adjustment grip 16, NC control pulse motors are attached to both ends of the cylindrical surface of the workpiece. Of course, it can also be used as an automatic taper correction system by installing a dimension measuring device.

[0012]

[Effect of the device]

 Since the present invention is configured as described above, it has the following effects. A center with a centering mechanism that rotatably supports a spindle with an eccentric taper hole and has means for rotating this spindle is mounted on a standard tailstock to perform taper adjustment, so it is expensive and dedicated. A tailstock with a unique taper correction function is not required, and highly accurate taper correction is possible with a compact accessory device. Moreover, since it is compactly integrated as an accessory device and the taper correction amount can be easily read directly with a general instrument such as a dial gauge, wide demand can be expected as an inexpensive attachment common to other devices.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a center with a centering mechanism of the present embodiment.

FIG. 2 is a sectional view of a spindle turning mechanism.

FIG. 3 is a front view of a center with a center adjusting mechanism.

FIG. 4 is a top view of a fine adjustment grip portion.

FIG. 5 is a top view of a cylindrical grinder.

FIG. 6 is a side view of a center centerline adjusting device for a tailstock according to the related art.

FIG. 7 is a sectional view taken along line BB in FIG.

FIG. 8 is a side view of a center center adjusting mechanism in another tailstock of the related art.

[Explanation of symbols]

10 Feed Screw 11 Tailstock Shaft 12 Case 12a Tapered Shank 13 Spindle 13a Eccentric Tapered Hole 14 Lever 15 Shifter Shaft 15a Shifter Fork 16 Fine Adjustment Grip 17 Frame 22 Center

Claims (1)

[Scope of utility model registration request] 1. A case having a taper shank portion detachably mounted on a tailstock shaft, a spindle having a taper hole rotatably supported in a center hole of the case and eccentric to a rotation axis, and A center that is detachably fitted in an eccentric tapered hole, a lever that is fixed to the spindle at a right angle, and a shifter fork that is provided in the case so as to be movable at a right angle to the shaft center and that engages with the lever tip portion are provided. A center with a center adjusting mechanism, comprising a shifter shaft having the shifter shaft and a feed screw for moving the shifter shaft, wherein a center eccentric about a center line of the tailstock shaft is swiveled to perform taper correction.