JPH0338070B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a profiling grindstone correction device for correcting a cylindrical grindstone having arcuate portions at both ends by profiling.

<Prior art> In such a conventional profiling grinding wheel correction device, as shown in FIG. Attached to the base 1, it is guided on the traverse table 2 and the ram 4 is attached to the tip.
A stylus S is attached to the rear end of the reciprocating member 3 on which the correction tool DT is mounted, and the stylus S is pressed against the template T by the pressing force of the pressing cylinder 5.
The grinding wheel G is corrected by traversing the traverse table 2 while being pressed against the grinding wheel G.

In addition, in such a profiling grindstone correction device, a lift cylinder 6 for shifting the advancing/retracting member 3 rearward is used.
In addition, a limit switch 7 and a dog 8 are provided to detect when the stylus S has come to the center of the straight portion Ta. Until the limit switch 7 is activated, the movement of the traverse table 2 moves the stylus S to the arc portion Tc of the template T. Shift the advancing/retracting member 3 backwards to a position where it can ride on the
When the limit switch 7 is activated, the lift by the lift cylinder 6 is released so that the stylus S can move along the other arcuate portion Tc.

However, in the profiling wheel correction device with such a configuration, a limit switch and a dog are required to detect when the stylus S passes through the center of the straight portion Ta, which not only complicates the mechanical configuration but also requires high precision. Since the lift cylinder 6 is operated during the process of correcting the cylindrical part Ga that needs correction, if the traverse table 2 vibrates due to the operation of the lift cylinder 6, this may have a negative effect on the correction accuracy of the cylindrical part Ga. Ta.

<Object of the invention> Therefore, the present invention makes it possible to control a lift cylinder without using a mechanical position detector such as a limit switch, and also improves the accuracy of grinding wheel correction of the cylindrical part by releasing the lift by the lift cylinder. It is an object of the present invention to provide a copying grindstone correction device that is simple in configuration and capable of highly accurate grindstone correction without affecting the grinding wheel.

<Structure of the Invention> In the present invention, the traverse table is fed by a servo motor, and the servo motor is driven by numerical control, so that the stylus rides on one arcuate portion, and the stylus rides on one arcuate portion. Numerical control means for providing a first movement of moving the traverse table until it is located near the end, and a second movement of moving the traverse table until the stylus passes through the other arcuate portion; control means for activating the lift device before the first movement is applied by the controller and deactivating the lift device in response to completion of the first movement, and activating the lift device near the end of the circular arc. This feature is characterized in that it is designed to release the .

<Examples> Examples of the present invention will be described below based on the drawings. In Fig. 2, G is a cylindrical grinding wheel having a straight part Ga on its outer circumferential surface and circular arc parts Gc, Gc at both ends of this straight part Ga, and this grinding wheel G is rotatable on a grinding wheel head (not shown). It is supported on the shaft and rotated around the axis OG.

A base 21 of the grinding wheel correction device 20 for correcting the grinding wheel G is fixed to the grinding wheel head, and a traverse table 23 is mounted on a guide surface 22 formed on the base 21 so as to be movable in parallel with the grinding wheel axis OG. The traverse table 23 is equipped with a servo motor.
A feed screw 24 rotated by the SMW is screwed together.

A reciprocating shaft 25 is supported on the traverse table 23 so as to be movable in a direction perpendicular to the moving direction of the traverse table 23, that is, in a radial direction of the grinding wheel G. A ram 26 that is slidably fitted in the forward and backward shaft 25 in the same direction as the sliding direction of the forward and backward shaft 25 is disposed, and a roll-shaped grindstone correction member is attached to the tip of the ram 26 on the grindstone side. A correction head 27 is mounted which supports the tool DT. The grindstone correction tool DT is rotationally driven by a motor (not shown). A feed screw 30 rotated by a servo motor SMU is screwed into the rear end of the ram 26, and the correction head 27 is moved forward and backward by the rotation of the servo motor SMU. In addition, in the above embodiment, the grinding wheel correction tool DT
Although a rotating roll type tool was used as the grinding wheel correction tool DT, a single diamond stone may also be used as the grinding wheel correction tool DT.

On the other hand, a template T having a straight portion Ta and arcuate portions Tc, Tc corresponding to the outer circumferential shape of the grinding wheel G is fixed to the base 21, and the stylus S in contact with the template T is attached to the rear end of the reciprocating shaft 25. Fixed. Further, a piston 3 is provided on the outer periphery of the advance/retreat shaft 25.
5 is formed, and a cylinder 36 into which a piston 35 is fitted is formed on the traverse table 23, and constitutes a pushing device that responds to the advance/retreat shaft 25 in the direction of the grindstone axis and maintains contact between the stylus S and the template T. do. This pushing device can be replaced with a spring or the like.

Further, a lift cylinder 40 is attached to the backward side of the traverse table 23 to move the advance/retreat shaft 25 rearward against the pressing force applied by the cylinder 36. That is, a piston 42 that is slidable in a direction parallel to the moving direction of the advance/retreat shaft 25 is fitted into the cylinder body 41 fixed to the traverse table 23, and the piston rod 43 of this piston 42 is inserted into the cylinder body 41. The engagement member 45 protrudes from the rear and faces an engagement portion 45a of an engagement member 45 fixed to the rear end of the forward/backward shaft 25. Further, ports 40a and 40b communicating with the front and rear cylinder chambers of the lift cylinder 40, respectively, are connected to a solenoid valve SV, and pressure oil is selectively supplied from a pump P (not shown).

When pressure oil is supplied to the port 40a, the piston 42 moves toward the engagement member 45,
When the stylus S is located at a position closer to the grinding wheel G than the position where the stylus S can be lifted up, which is shown as position Pc in FIG. position
Back up to PC. As a result, the stylus S at a position away from the arc portion Tc is moved to the traverse table 2.
3, it becomes possible to ride on the straight part from the circular arc part Tc. Also, port 40
When pressurized oil is supplied to b, the piston 42 moves toward the grinding wheel G, and the stylus S can move toward the grinding wheel G from the position Pc where it can ride, and the other end of the straight portion Ta The stylus S can now move by following the circular arc portion Tc.

In the present invention, as shown in FIG. 4, whether the stylus S moves to the right or to the left, the stylus S located at the end on the grinding wheel side is moved to a position Pc where the lift cylinder 40 can be operated.
The movement of the traverse table 23 is started with the traverse table 23 being moved back to the point where the stylus S has moved by a distance w1 and when it reaches Pl, Pl' near the end of the circular arc portion Tc, the lift operation of the lift cylinder 40 is released. After this,
The traverse table 23 is moved by distances w2 and w3 to correct the arcuate portion Gc of the grinding wheel G on the opposite side from the straight portion Ga. As a result, the lift release operation is performed during the correction of the circular arc portion Gc, which does not require very high correction accuracy, and the straight portion Ga can be corrected with high precision.

Next, a description will be given of the control device that corrects the grinding wheel G in the above-mentioned feed cycle. In FIG. 51, a pulse generation circuit 52, a data input device 53, and a hydraulic control circuit 55 are connected. The pulse generating circuit 52 is a servo motor.
Drive unit that drives SMW and SMU
It performs pulse distribution for DUW and DUU.
Pulse distribution is performed in accordance with commands from the numerical control device main body 50 based on numerical control data stored in the memory 51. Further, when a lift command is sent from the numerical control device main body 50, the hydraulic control circuit 55 energizes the solenoid of the solenoid valve SV to supply pressure oil to the port 40a of the lift cylinder 40, and commands a lift return command. When the solenoid valve SV is delivered, the solenoid of the solenoid valve SV is deenergized so that pressure oil is supplied to the port 40b side.

When a grinding wheel correction command is given to the numerical control device main body 50, the numerical control device main body 50 performs the process shown in FIG. Force,
Supply pressure oil to the port 40a side (i). As a result, the piston 42 moves toward the engaging member 45, the piston rod 43 comes into contact with the engaging portion 45a, and the stylus S is retracted from the original position shown by the solid line in FIG. 4 to the climbing possible position Pc.

When the lift operation is completed in this way, the drive unit is activated by the operation of the pulse generation circuit 52.
Distribute cutting pulses to DUU and drive servo motor SMU
, move the correction head 27 to the grinding wheel G side by the depth of cut Ua (ii), and then the drive unit
Positive pulses are distributed to the DUW at a period corresponding to the speed F1 to move the traverse table 23 to the right by a distance w1 (iii). As a result, the stylus S rides on the arcuate portion Tc of the template T and moves toward the Ta side.
The center of the stylus S is located at a position Pl a certain amount before the end of the arc portion Tc. At this point, the numerical control device main body 50 sends a lift return command to the hydraulic control circuit 55 (iv).

As a result, the solenoid of the solenoid valve SV is deenergized, pressure oil is supplied to the port 50b side, the piston 42 moves to the grinding wheel G side, and the stylus S moves to the arcuate portion Tc on the other end side. It becomes possible to move toward the grinding wheel G side from the position Pc where it can be climbed on.

Then, the numerical control device main body 50 again distributes pulses to the drive unit DUW, and moves the traverse table 23 by a distance w2 at a speed F2 suitable for correcting the straight line part Ga of the grinding wheel G. Ga is corrected (v), and the traverse table 23 is further moved by w3 at a speed F3 suitable for correcting the circular arc portion Gc to correct the circular arc portion Gc on the opposite side of the grinding wheel G (vi).

When the correction of the straight line part Ga and one arcuate part Gc of the grinding wheel G is completed in this way, the numerical control device main body 50 sends a lift command to the hydraulic control circuit 55 again (vii), and the stylus S is lifted up. Possible position Pc
back up to. Then, the traverse table 23 is moved to the left by a distance w1, and the stylus S is moved to the vicinity of the straight part Ta of the template T (viii), and after this,
A lift return command is sent to the hydraulic control circuit 55 to cancel the lift operation of the stylus S (ix). After that, the traverse table 23 is moved by a distance w2 to finish and correct the straight part Ga of the grinding wheel G by zero cutting (x), and the traverse table 23 is further moved by a distance w3 to correct the other circular arc part Gc (), Complete the grindstone correction operation.

In the above embodiment, in order to release the lift of the stylus S by the lift cylinder 40, the traverse table 23 temporarily stops when the traverse table 23 moves by a distance w1 from the end, and the feed is stopped in this vicinity. Although the correction accuracy is slightly deteriorated due to speed fluctuations, this operation is performed in the middle of the correction process of the circular arc portion Gc, which does not require much accuracy, so this does not affect the machining accuracy. Moreover, the deactivation of the lift cylinder 40 is performed by
During the process of correcting the arc part Gc, use the grindstone correction tool.
Since the traverse movement of the DT is performed in a stopped state, even if the traverse table 23 and the forward/backward shaft 25 vibrate due to the operation of the lift cylinder 40, this will not have an adverse effect on the grindstone correction accuracy. Further, the lift release position can be easily and accurately set by changing the ratio of the moving distances w1 and w2 of the traverse table 23. Therefore, it is possible to easily set the lift release position to an optimal range where the stylus S completes riding on the circular arc part Tc and does not reach the straight part Ta, making it extremely easy to set the lift release position. I can do it.

<Effects of the Invention> As described above, in the present invention, the lift release of the stylus is performed in conjunction with the numerical control operation that moves the traverse table, so the lift release position is controlled by a machine such as a limit switch. Not only can the detection be performed with high precision without using a standard detector, but this lift release is performed immediately before the correction of the straight part of the grinding wheel begins, which reduces vibration caused by the operation of the lift cylinder that performs the lift operation. Even if some unevenness occurs on the grinding surface of the whetstone due to a temporary stoppage of the traverse table,
This does not affect the correction accuracy of the straight line portion, which requires high correction accuracy, and allows highly accurate correction as a whole.

[Brief explanation of drawings]

Fig. 1 is a schematic plan view showing a conventional profiling wheel correction device, Figs. 2 to 4 show embodiments of the present invention, and Fig. 2 is a schematic plan view of the profiling wheel correction device showing a control circuit. The accompanying drawings, FIG. 3, are a flowchart showing the operation of the numerical control device main body 50 in FIG. 2, and FIG. 4 is a diagram showing the movement of the stylus S. 21...Base, 23...Traverse platform, 25
...Advancement/retraction axis, 26... Ram, 27... Correction head, 35... Piston, 36... Cylinder, 40
...Lift cylinder, 41...Cylinder body,
42... Piston, 43... Piston rod, 4
5... Engagement member, 50... Numerical control device main body, 5
2... Pulse generation circuit, 55... Hydraulic control circuit,
DT... Grinding wheel correction tool, G... Grinding wheel, Ga... Straight section, Gc... Arc section, S... Stylus,
SMU, SMW... Servo motor, SV... Solenoid valve,
T...template, Ta...straight line section, Tc...circular section.

Claims (1)

[Claims] 1 A device for correcting a cylindrical grinding wheel having arcuate portions at both ends by copying, which includes a traverse table guided and supported on a base so as to be movable in a direction parallel to the axis of the grinding wheel, and a servo. a feeding mechanism that is connected to a motor and moves the traverse table by the rotation of the servo motor; a template that is fixed on the base and has arcuate portions formed at both ends corresponding to the arcuate portion of the grinding wheel; and a grindstone correction device at the tip. a reciprocating member on which a tool is mounted and a stylus that is pressed against the template is attached to the retracting portion;
a lift device that moves the reciprocating member to a position where the stylus can ride on the straight portion of the template from the circular arc portion of the template by traversing the traverse table; A first movement in which the traverse table is moved until it rides on the circular arc portion and is located near the end of the circular arc portion on one side, and a second movement in which the traverse table is subsequently moved until the stylus passes through the other circular arc portion. numerical control means for applying two movements, and control by which the numerical control means activates the lift device before applying the first movement and deactivates the lift device in response to completion of the first movement; What is claimed is: 1. A copying grindstone correction device, characterized in that it is provided with means.