JPS6212484Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an apparatus for grinding workpieces having different lengths but the same shape.

Depending on the workpiece, the distance from one end to the machined part and the machined shape may be the same even if the total length is different, but in the past, when the total length of the workpiece changed, it was necessary to adjust the distance between the centers of the headstock and tailstock, etc. These setup changes are difficult to perform without manual adjustment by an operator, and it has been difficult to fully automatically process such workpieces.

By the way, although it is possible to adjust the distance between the centers to some extent by moving the center ram of the tailstock back and forth, there are some parts that cannot be machined if they are located on the headstock side. In other words, the end of the workpiece on the headstock side requires a part that engages with the drive member for rotationally driving the workpiece, so even if such a part and the machining location overlap or do not overlap, Machining is impossible if there is interference between the drive member and the grindstone corresponding to the location to be machined.

For such workpieces, the part to be machined must be located on the tailstock side, and in this state, if the center ram is advanced or retreated according to changes in the overall length of the workpiece, the part to be machined will not correspond to the grinding wheel, and the process will continue as it is. It cannot be processed.

Accordingly, it is necessary to move and position the table. On the other hand, in order to make the sizing device that measures machining dimensions correspond to the grindstone even when the table is moved, the sizing device must be supported on the bed side, which makes it difficult for workers to carry in and out of workpieces. This worsens operability. On the other hand, if the position of the headstock placed on the table is changed, there is no need to move and position the table, but such a setup change is extremely difficult.

In view of the above points, the present invention is designed to provide a center ram that can move forward and backward in the headstock, and to move this center ram back and forth in response to changes in the length of the workpiece for positioning. The objective is to enable machining without moving the grindstone, and to control the feed of the grindstone head using a sizing device installed on the table, thereby simplifying the configuration and ensuring good workability.

Embodiments of the present invention will be described below based on the drawings. FIG. 1 shows the structure of the headstock, and 10 is the main body of the headstock, which, like the tailstock 9, is placed on a table 8 placed on the bed. A sleeve 11 is fitted into the through hole 10a of the headstock body 10, and a flange portion 11a projecting from the center of the sleeve 11 is fastened to the shoulder portion 10b of the headstock body 10 with bolts 12. This sleeve 11
A drive pulley 14 is rotatably supported on the outer circumferential surface of one end by bearings 13, 13. A belt 18 is stretched between the drive pulley 14 and a pulley 17 fixed to one end of a rotating shaft 16 mounted in an eccentric hole 15a of a sleeve 15 for belt tension adjustment. Rotational force is transmitted from a drive motor (not shown) to a pulley 19 fixed to the other end of the rotating shaft 16 via a belt.

A center ram 21 having a center 20 mounted at one end is slidably inserted into the inner hole 11b of the sleeve 11. A cylinder 22 is bored at the other end of the center ram 21, and a piston 25 having piston rods 23 and 24 projecting from both ends is fitted into the cylinder 22. One piston rod 23 fits into a small diameter inner hole 26 concentrically drilled with the cylinder 22, and the other piston rod 24
protrudes outward through the cylinder cap 27, and is fastened with a nut 29 to a bottomed cylindrical bracket 28 fixed to the end of the sleeve 11. Two fluid passages 30, 31 are bored inside the piston rod 24 in parallel with the axis, and one end of each fluid passage 30, 31 communicates with left and right cylinder chambers 22a, 22b, which are separated by a piston 25, respectively. The other end of each fluid passage 30, 31 is an annular groove 32, which is formed on the outer peripheral surface of the piston rod 24.
It leads to 33. Passages 34 and 35 are bored in the bracket 28 in correspondence with the annular grooves 32 and 33, and pressure fluid is supplied and discharged from a fluid supply source to the passages 34 and 35 via an electromagnetic switching valve. A locking pin 36 is protruded from the cylinder cap 27 in parallel with the axis, and is inserted into the through hole 37 of the bracket 28.
The center ram 21 is inserted through the center ram 21 and acts to prevent the center ram 21 from rotating.

On the center side outer peripheral surface of the center ram 21, there is a second
As shown in the figure, a cylindrical member 42 is rotatably supported via bearings 41, 41. This cylindrical member 42
A protrusion 44 having a notch 44a is protruded from the outer peripheral surface of the drive pulley 14, and a drive pin 45 protruding from the end face of the drive pulley 14 in parallel with the axis engages with the notch 44a to prevent the rotation of the drive pulley 14. It transmits the signal to the cylindrical member 42 and allows the cylindrical member 42 to be displaced in the axial direction.

A large diameter hole 42a is bored in this cylindrical member 42 concentrically with the center 20.
Inside, a movable member 47 having an inclined groove 46 carved on the outer peripheral surface that is inclined with respect to the axis is attached to the end wall 42 at the bottom of the large diameter hole.
a spring 48 is compressed and loosely fitted between the
A presser cover 49 fixed to the opening end surface of the large diameter hole 42a
is in contact with. The inclined groove 46 of this movable member 47
An engaging pin 50 protruding toward the center of the cylindrical member 42 is engaged with the movable member 47, and the movable member 47 is rotated by moving in the axial direction.
A driving metal 43 that engages with a spline carved on one end of the workpiece W is held in this movable member 47 so as to be able to float in the radial direction, and is provided to protrude from the movable member 47 in the rotational direction. It is engaged with the engagement pin 51 and relative rotation is restricted. As a result, the rotational force of the drive pulley 14 is applied to the drive pin 45 and the protrusion 4.
4, cylindrical member 42, engagement pin 50, movable member 4
7. The rotation is transmitted to the driving metal 43 via the engagement pin 51, and the workpiece W engaged with the driving metal 43 is rotationally driven. Here, the cylindrical member 42, the driving metal 4
3. The movable member 47 constitutes a transmission mechanism 40 on the center ram 21 that transmits rotational force to the workpiece W.

As shown in FIGS. 3 and 4, the headstock 10 having the above structure is fixed on the table 8 together with the tailstock 9 at a predetermined distance. The cylinder 2 has a stroke equal to the change in length of the workpieces W ₁ and W ₂ supported at the center of the headstock 10 and the tailstock 9.
It is assumed that stroke number 2 has been selected. When machining a long workpiece _W1 , use bracket 2.
When pressure fluid is supplied to the passage 35 provided in the piston rod 24, the center ram 21, which is supplied with the pressure fluid from the passage 31 in the piston rod 24 to the cylinder chamber 22b, is positioned at the rearward end. In this state, the workpiece _W1 is carried in by a carrying device (not shown), and the center of the tailstock 9 moves forward to press the workpiece _W1 in the axial direction. If the splines on the shaft end of workpiece _W1 and the splines on drive metal 43 correspond to each other, drive metal 4
3, the movable member 47 is moved in the axial direction by compressing the spring 48, and is given rotation according to the lead of the inclined groove 46, so that the drive metal 43 and the workpiece
Spline engagement with the spline at the end of W ₁ axis is provided. When both ends of the workpiece _W1 are supported in the center in this way, the state shown in Fig. 3 is reached, and the machining location is
M ₁ corresponds correctly to grindstone 7. This rotates the drive metal 43 of the transmission mechanism 40 via the drive pin 45 and protrusion 44 that rotate the drive pulley 14, and the rotational force is transmitted to the workpiece _W1 , and by forward feeding of the grindstone 7, the workpiece _M1 is machined. is ground.

When machining a short workpiece _W2 , when pressure fluid is supplied to the passage 34 of the bracket 28, the pressure fluid is supplied from the passage 30 to the cylinder chamber 22a, and the center ram 21 is positioned at the forward end. When the workpiece W ₂ is carried in in this state and the center of the tailstock 9 moves forward to support the center, the machining location M ₂ of the short workpiece W ₂ will also correspond correctly to the grinding wheel 7 as shown in Fig. 4. . Therefore, by rotating the drive pulley 14 and moving the grindstone 7 forward, the short workpiece _W2 can be ground in exactly the same way as the long workpiece _W1 . Note that 6 in the figure is a rest device, which can be installed at the same position on the table even if the workpiece changes.

In this way, in the present invention, the spindle-side dead center moves forward and backward in response to changes in the length of the workpiece, and the transmission mechanism that transmits rotational force to the workpiece also moves together with the spindle-side dead center.
Even if the length of the workpiece changes, by positioning the dead center on the headstock side, the machining area on the tailstock side of the workpiece can be positioned at a fixed position corresponding to the grinding wheel even if the length of the workpiece changes, and rotation can be maintained. There is no need to move and position the table. Accordingly, since the sizing device can be installed on the table, obstacles on the front side of the machine can be eliminated, which has the effect of significantly improving the workability and operability of loading and unloading workpieces, etc.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention. Fig. 1 is a longitudinal sectional view of the entire headstock, Fig. 2 is an enlarged longitudinal sectional view of the main part of the center ram tip, and Figs. 3 and 4 are length diagrams. It is a figure which shows the processing state of a different workpiece. 10... Headstock, 11... Sleeve, 14...
Drive pulley, 21...center ram, 22...cylinder, 25...piston, 28...bracket,
30, 31...fluid passage, 40...transmission mechanism, 4
DESCRIPTION OF SYMBOLS 1... Cylindrical member, 42... Drive metal, 44... Protrusion, 45... Drive pin, 46... Inclined groove, 47...
...Movable parts.

Claims (1)

[Scope of utility model registration request] Workpieces of different lengths but with the same shape to be machined are rotatably supported between the centers of the tailstock and headstock, and the workpieces are ground by making the workpiece correspond correctly to the grindstone and feeding the grindstone forward. In the apparatus, the tailstock and the headstock are installed on a table provided on the bed, and a sleeve that rotatably supports a drive pulley that is rotationally driven by a rotational drive source is fixed to the headstock, and the sleeve is attached to the headstock. A center ram having a dead center for supporting a workpiece at its tip is slidably inserted in the center hole in the axial direction, and a transmission mechanism that engages with one end of the workpiece and transmits rotational force is attached to one end of the center ram. Bearing only rotation possible,
A drive pin that engages with this transmission mechanism and is parallel to the rotation axis of the drive pulley is provided protruding from the end face of the drive pulley, and one end of the center ram is provided with a plurality of center rams in accordance with the amount of change in the length of the workpiece. A feature is that a positioning device for positioning in the axial direction is connected, and the dead center on the headstock side is positioned with respect to workpieces of different lengths, and the machining part on the tailstock side of the workpiece is positioned at a fixed position. Grinding equipment.