JPS6071163A - Apparatus for truing angular type grinding wheel - Google Patents

Abstract

PURPOSE:To enable a pair of grinding surfaces to be trued with high accuracy irrespective of the displacement of the grinding surface of a grinding wheel by utilizing a truing tool feeding unit to correct the position of the truing tool. CONSTITUTION:A truing tool T is mounted on a movable head 18 moving forward and backward in the direction orthogonal to the axis of a grinding wheel G along a template 36, while being adjusted by a servomotor 30 with respect to the relative position. Also, by a grinding surface position detecting means 1 is detected the position of a pair of grinding surfaces Ga, Gb of the griding wheel G in the direction orthogonal to the axis of the grinding wheel G. A cut control means 2 rotates the servomotor 30 until a predetermined amount of cut is applied to the grinding surface Ga on the basis of the positional information of said detecting means 1, and then the movable head 18 is moved parallel to the axis of the grinding wheel G to true the grinding surface Ga. Next, a position correcting means 3 is operated to figure out an amount of deviation of the grinding surface position for correcting the position of the tool T.

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention relates to a truing device for an angular type grinding wheel, and particularly to a truing device for truing a pair of grinding surfaces of an angular type grinding wheel by tracing. .

<Prior Art> In recent years, so-called CBN grinding wheels using hard materials such as cubic boron nitride as abrasive grains have come into use. CBN grinding wheels are extremely expensive, so when truing the grinding surface, the depth of cut of the truing tool should be kept to the minimum necessary to remove the waviness of the grinding wheel, regardless of the thermal displacement of the grinding surface, and the life of the grinding wheel should be extended as much as possible. It is necessary to do so. For this reason, conventional methods have been adopted in which the position of the grinding surface is detected using a contact sensor, and the material is ground to a constant thickness from this grinding surface.

However, when truing an angular-shaped grinding wheel that has two grinding surfaces inclined with respect to the normal direction of the grinding wheel by tracing, a single contactor is brought into contact with one grinding surface of the grinding wheel. Highly accurate truing cannot be performed simply by detecting the position of one grinding surface.

That is, when truing a ground surface by moving the truing tool T following a template, as shown in FIG.
A predetermined depth of cut ΔC is applied from a state aligned with the grinding surface, and then the truing tool T is moved along the template to true the ground surfaces Ga and Gb. In this case, the position of the template was adjusted based on the grinding surfaces Gao and Gbo of grinding wheel G when the new grinding wheel was installed, so as shown by the two-dot chain line in Fig. 1,
When the positions of the grinding surfaces Ga and Gb of the grinding wheel G shift in the grinding wheel axis direction and the radial direction orthogonal to this, one of the grinding surfaces G
Even if the truing tool T is aligned with the grinding surface Ga at a, if the truing tool T is moved from this state following the template, a normal cut will not be made on the other grinding surface Gb, and truing will not be possible.

<Purpose of the Invention> Therefore, the present invention aims to enable a pair of grinding surfaces to be trued with high precision regardless of changes in the position of the grinding surfaces of the grinding wheel in a device that trues such an angular-shaped grinding wheel by tracing. purpose.

Another object of the present invention is to make it possible to correct the position of a truing tool by using the cutting feed device of the truing tool.

<Configuration of the Invention> FIG. 2 is an overall configuration diagram for clearly demonstrating the present invention. The truing tool T is mounted on a movable head 18 that moves forward and backward in a direction perpendicular to the axis of the grinding wheel G following the template 36, and this movable head 18 has a sliding head 18 that moves forward and backward in the direction perpendicular to the axis of the grinding wheel G following the template 36. The position of the moving body 26 in a direction perpendicular to the grinding wheel G can be adjusted, and this relative position is adjusted by the servo motor 30. In addition, 1 is a pair of grinding surfaces Ga of the grinding wheel G.
.

A grinding surface position detection means for detecting the position of Gb in a direction perpendicular to the axis of the grinding wheel G, which includes a pair of grinding surfaces Ga,
Position information ΣEa according to the position of Gb.

Output ΣEb.

Based on the position information from the grinding surface position detection means 1, the cutting control means 2 rotates the truing tool T by 30 rotations of the servomorph until a certain amount of cut is applied to one of the grinding surfaces Ga on which truing is first performed. After that, the movable head 18 is moved in a direction parallel to the axis of the grinding wheel to perform truing of one of the grinding surfaces Ga.

When the truing of one of the ground surfaces Ga is completed, the position correction means 3 is activated in response to this, and the deviation amount of the pair of ground surface positions detected by the ground surface position detection means 1 is converted into a pair of position information ΣEa, ΣEb. Based on the difference, the servo motor 30 is rotated to correct the position of the truing tool.

As a result, the truing tool T is moved forward or backward by the difference in radial position between the pair of grinding surfaces Ga and Gb, and the other grinding surface cb is also trued with high precision.

<Example> Embodiments of the present invention will be described below based on the drawings.

In FIG. 3, reference numeral 10 denotes a grinding wheel head, and an angular-shaped grinding wheel G having a pair of grinding surfaces Ga and Gb orthogonal to each other is supported on the front part of the grinding wheel head 10, and is rotated by a drive motor in an enclosure. It looks like this. A cavity 10a is formed at the rear of the whetstone head 10, and the cavity 10a of the whetstone head 10
2. A fixed base 11 is provided on the lower surface of the fixed base 1.
A traverse slide 12 is engaged and supported on the grinding wheel G so as to be able to reciprocate in parallel with the axial direction of the grinding wheel G. Further, a servo motor 13 for traverse is fixed to the left end of the fixed base 11, and a feed screw 14 provided on the rotating shaft of this servo motor 13 is screwed into a feed nut 15 provided on the traverse slide 12, so that the servo The forward and reverse rotation of the motor 13 reciprocates the traverse slide 12 in the left and right directions. Then, the cavity 1 of the traverse slide 12. In front of the right side protruding from Oa, a truing tool T consisting of a diamond roll is attached to a grinding wheel G.
It is supported so that it can move forward and backward in a direction perpendicular to the axis of the

That is, a ram 16 and a guide bar 17 that are movable in a direction perpendicular to the axis of the grinding wheel G are guided and supported on the traverse slide 12.
A movable head 18 rotatably supporting a truing tool T is attached to the tip of the movable head 18. A support shaft 19 that supports the truing tool T is connected to a drive motor 23 attached to the grindstone head 10 via a flexible power transmission shaft 20, a relay shaft 21, and a heald transmission mechanism 22.
is rotated at a predetermined rotation speed.

On the other hand, at the rear of the traverse slide 12 opposite to the grinding wheel G, there is a sliding tube 2 that can slide on the same axis as the ram 16.
5 is provided, and a sliding body 26 is fixed to the rear end of this sliding tube 25, and this sliding body 26 is connected to the screw I/
The connecting rod 28 is connected to the connecting rod 28.

A servo motor 30 for cutting is fixed to the sliding body 26, and a feed screw 31 connected to the rotating shaft of the servo motor 3o is screwed into a feed nut 32 provided on the ram 16. Ram 16 by forward and reverse rotation
is set to move forward and backward. Further, a stylus take-up shaft 33 is fixed to the sliding body 26 in parallel with the feed screw 31, and a stylus 34 is fixed to the tip of the stylus take-up shaft 33. And this stylus 34
is in contact with a tracing surface formed behind the tenbrae 1-364, which is fixed to the upper wall tab of the whetstone head 10 via the tenbrae 1-mounting base 35.

Further, a support block 40 is fixedly installed on the upper part of the movable head 18, and a cutting shaft 41 having several contact detectors S at its tip on the side of the grinding wheel G is attached to the supporting block 40.
is movably guided in a direction perpendicular to the axis of the A feed screw 43 rotated by a servo motor 42 attached to the rear end of the support block 40 is screwed into this cutting shaft 41, and the rotation of the servo motor 42 advances the cutting shaft 41 by a fixed amount. It is designed to let you do so.

As shown in FIG. 5, the tip of the contact detector S has a first contact surface parallel to the ground surfaces Ga and Gb.
A contact portion Sa and a second contact portion sb are formed, and a vibration sensor 45 is attached to the base of the contact portion Sa and a second contact portion sb.
The contact of the grinding wheel G with the grinding wheel G of the second contact portion Sb is detected by vibration.

FIG. 6 is a block diagram showing a control circuit, in which a memory 51 is connected to the printer 50, and a data input device 52 is connected to the ink face ID 1 connected to the computer 50. A contact detection circuit 53 is connected to detect that the contact detector S has contacted the grinding wheel G based on a signal from the vibration sensor 45. In addition, the ink face IF2 includes drive units DUW, DUU, DUV for driving the servo motors 13, 30.43,
A hydraulic control circuit 54 for driving the hydraulic cylinder is connected.

Next, the operation of the angular grinding wheel truing device having the above configuration will be explained. Before the truing operation is started, the 1-rubber slide 12 is located at the original position shown in FIG. 3, and the first contact portion Sa of the contact detector S is located at the original position shown in FIG. In addition, it is located at a position PO where the U-axis coordinate value is R+A, which is set back by a certain distance A from the grinding surface Ga' immediately after the previous truing.

Note that R is a value depending on the radius of the grinding wheel G.

When a truing command is given in this state, the computer 50 starts executing the program shown in FIG. First, in the steering knob 100, the movable head 18 is advanced toward the axis of the grinding wheel G by distributing pulses to the U axis. When the vibration sensor 45 detects contact with Qa, the feed is stopped (point P1 in FIG. 8).The amount of feed at that time is then stored as MR in step 104.

uIj This value of MR represents the position of the grinding surface Ga with respect to the movement start point PO of the contact detector S. After this, in step 106, the contact detector S is set to P. After retracting a certain amount backward from the workpiece to the relief position P2 where the U-axis coordinate value is R+H, in step 108, a pulse is distributed to the workpiece W-axis to activate the servomorph 13 in order to measure the position of the grinding surface Gb. The contact detector S is shifted to the right side in the figure by a certain amount, and the second contact part sb is shifted to the position shown by the dashed line in FIG. It is in a state where it is separated by a certain amount B from the grinding surface Gb' which descends immediately after the truing of the first time.Then, in step 110, the contact detector S is sent until it makes contact, as described above, and then in step 114, the feed amount is stored as NR.

That is, this NRO value is based on the ground surface Gb with position P3 as a reference.
Indicates the location of Thereafter, in step 118, the contact detector S is moved back to position P5.

As described above, the positions PO and P3 are the ground surface Ga' immediately after the previous truing.

They are located at positions A, B, and backward from the position of Gb', respectively, and from these points po and P3, the first contact portion Sa and the second contact portion
Difference ΔE between the amount of movement MR, NR that the contact portion sb has moved until it comes into contact with the grinding surfaces Ga, Gb and the above-mentioned constant retreat amounts A, B
a and ΔEb represent the amount of thermal displacement in the radial direction based on the ground surfaces Ga', Gb' immediately after the previous truing of each ground surface Ga, Gb. Step li8 is a step for calculating the thermal displacement amounts ΔEa and ΔEb.

When the amount of thermal displacement in the half (row direction) of the ground surfaces Ga and Gb is detected in this way, the computer 504J step 12
0, both EJ and displacement amount ΔEa.

ΔEb is added to the cumulative values ΣEa and ΣEb to update the cumulative values ΣEa and ΣEb, and step 1
In step 22, the corrected movement amount Vc is calculated by subtracting ΣEb from the cumulative value ΣEa.

The cumulative values ΣEa and ΣEb are reset to zero when a new grinding wheel G is installed and the positions of the grinding wheel G and the template 36 are aligned, and thereafter, each time truing is performed, the displacement of each grinding surface Ga, Gb is calculated. Since the amounts ΔEa and ΔBb are accumulated, the cumulative values ΣEa and ΣEb are calculated based on the position of the ground surface Ga (1, GbO) immediately after being aligned with the tracing surface of the template 36, as shown in FIG. It represents the amount of positional deviation between the grinding surface −Ga and Gb.The correction value Vc is the amount of positional deviation between the truing tool T and the grinding surface Ga.
, after truing the ground surface Ga by giving a certain amount of radial depth of cut ΔC to Gb, the ground surface Gb
It also represents the corrected movement amount of the truing tool T necessary to give the same radial depth of cut ΔC (=J).

In this way, the positional deviation amount ΣE of each grinding surface Ga, Gb
a, ΣEb and truing tool TM Is it necessary when moving from the grinding surface Gb to the grinding surface Ga? ili positive movement amount Vc
When the calculation is completed, the computer proceeds to step 124.
In step 128, the U-axis coordinates of the copying start position P7 are calculated by calculating [n-ΔC+ΔEa], and in step 128, pulse distribution is performed to the U-axis and the W-axis in order to position the truing tool r at the copying start position P7. conduct. In addition,
R is a value representing the radius value of the grinding wheel G. As a result, the truing tool T is positioned at a constant depth of cut ΔC with respect to the grinding surface Ga of the grinding wheel G, and at a position close to the axis of the J grinding wheel G. Thereafter, in step 126, pulse distribution to the W axis is performed. 1, and move the traverse slide 12 to P8, where the squirrel 34 is located at the top of the template 36. Thereby, the grinding surface Ga of the grinding wheel G is trued to image accuracy related to thermal displacement, following the template 1-36.

When the truing of the grinding surface Ga is completed in this way, in step 128, the truing tool T is pulse-distributed to the U-axis until the truing tool T reaches the position P9 where the U-axis coordinate becomes R-ΔC-Vc. As a result, the truing tool T is moved forward by the difference Vc between the surface positions of the grinding surface Ga and the grinding surface cb,
The truing tool T cuts into the ground surface Gb by a constant depth of cut ΔC. Then, in step 130, pulses are distributed to the W axis until the traverse slide 12 is located at the leftward end. Thereby, the truing tool T moves following the template 36, and the grinding surface Gb is trued. As described above, when the stylus 34 reaches the apex of the template 36, the front surface Ga of both sides is removed.

Since the position is corrected by the difference Vc in the radial position of cb, even if there is gH;5 displacement on the ground surface Gb, the ground surface Gb
This allows for highly accurate truing.

When the truing is completed in this manner, the computer 50 performs a process of correcting wear of the first contact portion Sa and the second contact portion sb of the contact detector S during contact detection in steps 134 to 146.

That is, in step 134, the computer 50 subtracts the truing depth of cut ΔC from the grindstone diameter R to make the value of the grindstone diameter R match the grindstone diameter after truing, and then,
After distributing a certain number of pulses to the V axis in step 136 to advance the contact detector S by a certain amount, in step ]48, contact 11I! I: Pulse distribution is performed to the U-axis and W-axis in order to move the detector S to the above-mentioned position PO at an immediate feed speed. After that, in step 140, when the number of pulses corresponding to the constant HIA is distributed to the U axis, the tip of the first contact portion Sa of the contact detector S is cut by coming into contact with the grinding surface Qa, and the grinding surface Ga The contact surface of the first contact portion Sa coincides with the contact surface of the first contact portion Sa. As a result, when the truing tool '1' is positioned at the grinding wheel diameter R-1-A during the next truing, the first contact part Sa is positioned at a position that is retreated by a certain amount A from the ground surface Ga after truing. will be done.

In the subsequent step 146, the truing tool T is rapidly moved to the above-mentioned point WP3, and then in step 148, the number of pulses corresponding to the fixed amount B is distributed to the second contact portion. sb is brought into contact with the grinding surface Gb to cut the second contact portion Sb. This allows the second
The contact surface of the contact portion sb coincides with the grinding surface cb, and when the truing tool T is positioned at R+B during the next truing, the second contact portion sb is retracted by a certain amount B from the grinding surface Gb.

In this way, the first contact portion Sa and the second contact portion Sa of the contact detector S
The contact surface of the contact part sb is the ground surface Ga, G after truing.
Since the correction is made based on point b, the first contact portion 3a, the second
Even if the contact portion sb is worn at the time of contact detection, the thermal displacement amounts ΔEa and ΔBb of these ground surfaces Ga and GbO can be detected with high accuracy.

<Effects of the Invention> As described above, in the present invention, each of the position changes in the radial direction of a pair of grinding surfaces is detected, and correction is performed based on the deviation in the amount of position change between the detected pair of grinding surfaces. The amount of movement is calculated, and when moving from truing one grinding surface to truing the other grinding surface, the position of the truing tool is corrected based on this calculated correction movement amount. It has the advantage of being able to truing both with high precision.

Further, in the present invention, since the position can be corrected using the cutting device of the truing tool, there is an advantage that no special feeding mechanism is required for position correction.

[Brief explanation of the drawing]

Fig. 1 is a diagram showing the influence of thermal displacement of the grinding surface of the grinding wheel on truing, Fig. 2 is an overall configuration diagram to clarify the present invention, and Figs. 3 to 1O show examples of the present invention. Figure 3 is a plan view of a grindstone head equipped with a truing device;
4 is a sectional view taken along the line IV-IV in FIG. 3, FIG. 5 is a partial sectional view taken from the ■ direction in FIG.
The figure is a block diagram showing the control circuit.
1 does not indicate the operation of the computer 50 shown in FIG.
Coach 1-1 Figure 8 shows the feed cycle, Figure 9
Figures (al, !b) are diagrams showing the positional relationship between the contact detector S and the grinding wheel G during contact detection, and Figure 10 is a diagram showing the positional relationship between the contact detector S and the grinding wheel G during contact detection.
FIG. 3 is a diagram showing the relationship between the position change and the corrected movement amount Vc. 12... Traverse slide, 18... Movable head, 30... Servo motor, 31... Feed screw, 33
...Stylus mounting shaft, 34...Stylus, 36
...Template, 45...Vibration sensor, G...
Grinding wheel, Ga, 'Gb... Grinding surface, S... Contact detector, Sa... First contact part, sb... Second contact part, T
...Truing tool, Vc...Movement correction amount. Patent applicant Toyota Machinery Co., Ltd. Figure 7 (Q) Figure 7 (b)

Claims (1)

[Claims] (1) The angular-shaped grinding wheel is moved forward and backward in a direction orthogonal to the axis of the grinding wheel following a template having a tracing surface of a shape corresponding to a pair of grinding surfaces, and the grinding wheel axis line relative to the template is moved by a drive device. In a truing device for an angular grinding wheel, which includes a truing tool whose position in an orthogonal direction is changed, a grinding surface position detection that detects a position of a pair of grinding surfaces of the grinding wheel in a direction orthogonal to the grinding wheel axis line. and cutting control means for applying a certain amount of cut to the one ground surface detected by the grinding surface position detection means with the truing tool before truing one of the ground surfaces;
When the truing of the one grinding surface is completed, the position of the truing tool is corrected by the drive device according to the amount of positional deviation between the pair of grinding surfaces detected by the grinding surface position detection means. A truing device for an angular grinding wheel, characterized in that it is equipped with a position correction means.