JPS6071162A - Position correcting device in angular grinding machine - Google Patents

Abstract

PURPOSE:To grind a shoulder of a workpiece with high accuracy by detecting the displacement of a grinding wheel to correct the relative position of the workpiece to the grinding wheel so that a passage through which the top of the grinding wheel passes by a theoretical set pass point. CONSTITUTION:An angular grinding machine moves a workpiece W parallel to the axis of a spindle to locate axially the workpiece W, and then feed an angular type grinding wheel G having a pair of grinding surfaces Ga, Gb orthogonal to each other in the direction of crossing the axis of the spindle to work an end face Wb of a shoulder of the workpiece W. This grinding machine is provided with a displacement detecting means 1 for detecting the displacement of a top P in which grinding surfaces Ga, Gb of the grinding wheel G cross each other in the direction parallel to the axis of the spindle and a position correcting means 2 for correcting the relative position of the workpiece W to the grinding wheel G according to the amount of the displacement detected by the displacement detecting means 1 such that a passage of the grinding wheel G passing by the top P of the grinding wheel G passes by a theoretical pass point set on the work piece W.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a position correction device for an angular grinding machine.

<Prior art> Generally, when grinding the shoulder part of a workpiece at the same time as grinding the cylindrical part of the workpiece, an angular grinder having a cylindrical part grinding surface for grinding the cylindrical part of the workpiece and a shoulder part grinding surface for grinding the shoulder end face is used. The workpiece is machined using an angular grinding machine equipped with a shaped grinding wheel, but in such a grinding machine, the grinding surface of the cylindrical part of the grinding wheel and local grinding occur due to thermal expansion and contraction of the grinding wheel shaft, abrasion of the front surface of the grinding wheel, etc. The position of the top, which is the intersection of the surfaces, is displaced,
As a result, if the position of the path through which the top of the grinding wheel passes is displaced in the direction parallel to the workpiece axis, the position of the shoulder grinding surface will not be constant when the cylindrical part of the workpiece is ground to a predetermined dimension.
It becomes impossible to accurately grind the shoulder end face to the predetermined dimensions.

For this reason, in conventional angular grinding machines, as shown in Fig. 1, the depth of cut at the time of truing is set large, and after truing, the position of the top part 1) of the grinding wheel G in the direction parallel to the grinding wheel axis is I tried to keep it in the same position.

However, when such truing is performed, if an appropriate depth of cut is given on one ground surface Gb, more of the abrasive grain layer is removed than necessary on the other ground surface Ga, and cubic boron nitride, etc. It is not preferable to perform such truing with expensive grinding wheels that use hard material as abrasive grains, and it is preferable to perform truing with the minimum depth of cut that can remove the waviness of each grinding surface Ga and Gb. It becomes necessary. However, when such truing is performed, as shown in Figure 1fb), the position of the top P of the grinding wheel G is not constant, resulting in the problem that the shoulder end face of the workpiece cannot be precisely ground to the predetermined dimensions. There is.

<Purpose of the Invention> Therefore, the present invention is designed to enable highly accurate grinding of the shoulder α11: surface of a workpiece even if the position of the m part of the grinding wheel is displaced due to thermal expansion and contraction of the grinding wheel shaft, etc. The purpose is to enable high-precision machining of the shoulder end face of a workpiece with minimal truing.

<Configuration of the Invention> FIG. 2 is an overall configuration diagram for clearly demonstrating the present invention. During truing, the displacement detection means 1 measures the displacement of the top portion P in a direction parallel to the grinding wheel axis by detecting, for example, the radial position of the pair of grinding surfaces Ga and Gb of the grinding wheel G, and outputs this. . When the displacement amount of the top P is detected by the displacement detection means 1, in response, the position correction means 2 operates the servo motor 3 according to the detected amount of displacement to move, for example, the workpiece table 4. , to move the workpiece W in the axial direction.

Thereby, even if the position of the top P is displaced, the relative position of the path through which the top P passes with respect to the workpiece W remains constant, and the shoulder end surface wb of the workpiece W can be ground with high precision.

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

In FIG. 3, reference numeral 11 denotes a workpiece table that supports a workpiece W by a headstock 12 and a tailstock 13.
5.16, the feed screw 18 is slidably guided in the Z-axis direction parallel to the Φ+b line of the workpiece W, and is rotated by the -1)-bomotor 17! I'm in agreement. Note that 19 indicates an end face sizing device installed on the head 10.

On the other hand, behind the bed 10, a grindstone head 20 is placed on a guide surface 21.
．． 22, a feed screw 25 is slidably guided in an oblique X-axis direction at a constant angle θ with respect to the spindle axis O8, and is engaged with a feed screw 25 rotated by a servo motor 23. An angular-shaped grinding wheel G having a cylindrical grinding surface Ga parallel to the axis of the workpiece W and a local grinding surface Gb perpendicular to the grinding surface Qa is mounted on the front side of the workpiece W.

On the other hand, at the rear side of the grinding wheel head 20, as shown in FIGS. 4 to 6, a tracing-type truing device 30 and a surface position detection device 40 for detecting the surface position of the grinding surface of the grinding wheel are installed. It is being

As shown in FIG. 4, the truing device 30 is placed on a traverse table 32 that is moved by a cylinder 31 in a direction parallel to the axis of the grinding wheel G, and is moved in a direction perpendicular to the axis of the grinding wheel G following a template 33. A truing head 36 is attached to the tip of the advancing/retracting platform 35, which guides the advancing/retracting platform 35 and has a truing vehicle T mounted thereon. The advancing/retracting table 35 is provided with a feed screw 38a that is screwed into a ram portion 37 integral with the truing head 36 and rotated by a servo motor 38. Further, the support base 34 that supports the template 33 is screwed with a feed screw 39 rotated by a servo motor 39.
The position of the grinding wheel G in the direction parallel to the axis is adjusted by the rotation of the grinding wheel G.

On the other hand, the surface position detection device 40, as shown in FIG.
A grinding wheel G is mounted on a shift table 42 that is shifted by a cylinder 41 by a certain distance in a direction parallel to the axis of the grinding wheel G.
It is movable in the direction perpendicular to the axis of the
A ram 43 with a servo motor 44 attached thereto is provided, and a feed screw 45 rotated by a servo motor 44 is screwed to the rear end of the ram 34. At the tip of the contactor S, a first contact surface is formed, which is parallel to the ground surfaces Ga and Gb.
While the contact portion S+a and the second contact portion sb are formed,
A vibration sensor 46 is attached to its base, and detects the contact of the first contact portion Sa and the second contact portion Sb with the grinding wheel G by vibration.

Next, to explain the control circuit, in FIG.
is a computer, a memory 51 is connected to this computer 50, and a contact detector is connected to the ink face 1F'■ connected to the computer 50 by a data input device 52 and a signal from a vibration sensor Contact detection circuit 5 that detects that S contacts the grinding wheel G
3 is connected to a sizing circuit 54 that detects when the output of the end face sizing device 19 becomes zero. In addition, the ink face IF2 has a servo motor of 23.17°38.3°.
9. Drive unit DUX that drives each of 44
,DUZ,DUU,,DUV,I]UW are connected.

Now, when a truing command is given to the computer 50, the computer 50 performs the processing shown in FIG.

Steps 100 to 116 are steps for detecting the positions of the grinding surfaces Ga and Gb of the grinding wheel G with respect to the origin of the contacts, and by distributing pulses to the U axis, The contact S, which is in the state shown by the dashed line, is moved toward the center axis of the grinding wheel G. Then, when the first contact portion Sa comes into contact with the grinding surface Ga, the contact drive device is stopped. , the feed amount is stored as MR in step 104.The value of this MR represents the position of the grinding surface Ga with the origin of the contact S as a reference.After the contact is returned to the origin in step 106, , then in order to measure the position of the grinding surface Gb,
As shown in b), operate the shift ring to shift the contact S to the right side in the figure, and move the second contact part sb to a predetermined position in the V-axis direction in a direction parallel to the grinding wheel axis. shift.

Then, in step 110, as described above, after the contactor is fed until it makes contact, the feed amount is recorded as NR. Is this NR value based on the origin of the contact S? if indicates the position of the cut surface G&. after that,
In step 116, the contact S is returned to its origin. In this way, the position of the grinding surface immediately before truing is detected as the amount of movement of the contact S.

Next, in step 118, MR-MO, NR-No.
The displacement A of the feed amount of each contact portion S'a, Sb is calculated by calculating
, put B. That is, as described later, MO, No is the value of each contact portion Sa measured immediately after the previous truing.
, Sb is a stored value of the amount of movement until it comes into contact with the grinding surfaces Ga, Gb, and the values of A and B calculated in step 118 are the values for each grinding surface Ga, Gb as shown in FIG. 10 (al, fbl). Each represents the displacement of Gb in the 1J axis direction.

Next, in step 120, the displacement amounts ΔU and 8V of the top P of the grinding wheel G in the U-axis direction and V-axis direction are calculated using the following equations (1, 1, and (21), respectively, and the top The amount of displacement ΔZ in the Z-axis direction parallel to the axis of the workpiece W on the path R through which P passes is calculated.

ΔV-(A-B) sinθ' cosθ −・−+1
．． )ΔU=Asin2θ+Bcos2θ −−・+21
Δ7. = (A-B) cosθ...+31
FIG. 11 shows the semi-longitudinal displacement iA, 1 of the ground surfaces Ga and Gb.
3 and the amount of displacement in each axis direction ■, ΔU.

It is a figure showing the relationship of ΔZ.

In this way, the deviation of the top P of the grinding wheel G in each axial direction 1) Δ■
, ΔU, and ΔZ are settled, in step 122, the servo motor 39 is operated to move the tenbranes 1 and 33 in the direction of the V axis of ΔV, and the top of the template changes the position of the top P of the grinding wheel G. Move accordingly. Next, in step 124, drive the servo motor 44,
The truing tool is advanced by Δυ10 in the normal direction (U axis direction), and the truing wheel T is placed at a position close to the axis of the grinding wheel G by a certain depth of cut ic with respect to the grinding surface Ga. Position.

Next, in step 126, the traverse cylinder 41 is operated and the truing tool T is moved from tracing the template 33 to grinding wheel surfaces G11l and Gb.
(J grinding. After grinding, traverse cylinder 41,
The truing tool T is operated in the opposite direction to move the truing tool T in the positive direction of the V-axis to the origin position, thereby completing the truing. Thereafter, in step 130, the grindstone head is advanced by ΔU+C in the normal direction. As a result, the ground surface Ga
The position viewed from the workpiece W side is the same as the position of the ground surface Ga before truing.

Next, in steps 132 to 144, the contact S is brought into contact with the ground surface immediately after truing, and the ground surface Ga, G
This is a process of measuring and storing the position of b with reference to the origin of the contact. Step 134 is the step 100.1 described above.
It is the same as 02.

In addition, in step 136, the detected movement amount is stored in the MO as the position of the (υ) front surface immediately after the previous true ink. In step 138, after returning the contact to the origin, the contact is moved by K. Shift in one direction, and measure the feed amount in the same way for the other grinding surface Gb in step 140.
intended. Next, in step 144, the contact S is moved to the origin f
jL Finish after 1m. Through the above-described processing, the grinding wheel can correct errors caused by displacement in the axial direction and perform trueing of the front surfaces Ga and Gb with high accuracy.

Then, when the truing of the ground surfaces Ga and Gb is completed by the above processing, in step 146, the displacement amount ΔZ calculated in the above-described step 120 is calculated? ili is registered as a positive value and added to CVR to update the corrected movement amount CV in the workpiece table 11.

This correction value register VCR is reset to zero when a new grinding wheel G is installed and the positional relationship between the top P of the grinding wheel G and the top of the template 33 is aligned.
The displacement amount ΔZ is cumulatively added each time truing is performed. Therefore, the value of the correction value register VCR is the template 3 whose position does not change due to thermal expansion and contraction of the grinding wheel.
Path R along which the top P of the grinding wheel G passes, based on the top of 3.
This represents the amount of positional deviation in the direction parallel to the workpiece W axis.

On the other hand, when a machining command is given to the computer 50, the computer 50 performs the table positioning process shown in FIG. 9, and then executes a cutting program (not shown).

In step 200, the end face sizing device 19 is advanced so that the feeler of the 1.1it surface sizing device I9 can engage with the reference surface Ws of the workpiece W as shown in FIG. 12, and then in step 202 Pulse distribution is performed on the Z axis to position the workpiece table 11 at a position where the output of the end face sizing device 19 is zero.

As a result, a plane passing through the reference end surface Ws of the workpiece W is located at the intersection cpo of the spindle axis OS and the path RO through which the top of the grinding wheel G passes when there is no thermal displacement.

Furthermore, after this, in step 204, the reference end surface Ws
Based on the amount of deviation in the direction parallel to the workpiece axis direction between /2
tan θ) .

And with this (mugi, step 208) 7. +l
Pulse distribution is performed on the i-mountain, and the workpiece W is moved by a moving amount Zβ.
Move to the left in FIG.

As a result, the workpiece W is positioned at a position where R of the grinding wheel G passes through the intersection of the shoulder h::J surface Wa and the cylindrical portion wb upon completion of grinding.

In this way, the shift amount S of the workpiece table 11, which is determined by the shape of the workpiece W, is corrected by C, which is proportional to the thermal displacement amount of the top P of the grinding wheel G, and the movement amount Zρ of the workpiece table 11 is calculated. Therefore, after such positioning operation, the top P of the grinding wheel G is
The path R through which the shoulder part end face Wa and the cylindrical part wb during finishing
The state passes through the intersection of .

Therefore, by executing the subsequent machine program, the grinding surface Ga is engaged with the cylindrical part Wa, and the cylindrical part Wa is ground to the finished dimension based on the signal from the sizing device of the enclosure. The end face wb is ground with high precision to the specified finishing dimensions.

In the above embodiment, the workpiece table 11 was moved in accordance with the thermal displacement of the top P of the grinding wheel G. A drive device 27 that drives the grindstone shaft 26 that supports the wheel G by a servo motor 28 may be provided to move the position of the grindstone G in a direction parallel to the grindstone shaft 26.

In this case, the amount of movement of the grinding wheel 26 is determined by step 12 in FIG.
The displacement in the v-axis direction calculated at
6 may be moved.

<Effects of the Invention> As described above, in the present invention, the displacement of the top of the grinding wheel is detected, and the relative position between the workpiece and the grinding wheel is corrected accordingly. Since the route to be traced passes through the theoretical passing point set on the workpiece, even if the position of the top of the grinding wheel changes due to thermal expansion and contraction of the grinding wheel shaft, the shoulder of the workpiece can be traced with 111" accuracy. It becomes possible to grind to.

Therefore, even if truing is performed to minimize the amount of material removed on the grinding surface of the grinding wheel during truing, the machining accuracy of the shoulder of the workpiece will not deteriorate, and the wear amount of the grinding wheel will increase. This has the advantage that the machining accuracy of the workpiece can be improved without causing any damage.

[Brief explanation of the drawing]

FIG. 1 (al is a diagram showing truing in which the position of the top P of the grinding wheel G does not change, FIG. 1 (bl is a diagram showing truing in which the consumption amount of the grinding wheel G is reduced, and FIG. 2 is a diagram showing the present invention) 3 to 12 show embodiments of the present invention, FIG. 3 is a schematic plan view of the grinding machine, and FIG. 4 is a diagram of the truing device 30 in FIG. 3. An enlarged view, FIG. 5 is a cross-sectional view taken along the line V-V in FIG. 4, FIG. 6 is a cross-sectional view taken along the line Vl-Vl in FIG. 5, and FIG.
The figure does not show the control circuit, but is a block diagram, Figure 8 is a flowchart showing the operation of the computer 50 in Figure 7, and Figure 10 is a flowchart showing the operation of the computer 50 in Figure 7. A diagram showing the positional relationship between the contact S and the grinding wheel G,
FIG. 11 is a diagram showing the relationship between the displacement of the grinding surfaces Ga and Gb and the displacement of the top P, and FIG. 12 is an explanatory diagram for explaining the positioning operation of the workpiece W. 11...Workpiece table, 12...Spindle ffi, 1
3...Tailstock, 17...Servo motor, 20...
Grinding wheel head, 23... Servo motor, 30... Truing device, 40... Surface position detection device, 50... Computer, 53... Contact detection circuit, G... Grinding wheel, ■)...・Top, R...route, S...contact,'
r...Trueing car. Patent Application Humanoid Mouth” Koki Co., Ltd. Figure 2 Figure 3 Figure 4 Figure 9 Figure 10 (C1) Figure 11 Figure 12

Claims (3)

[Claims] (1) Move the workpiece in a direction parallel to the spindle axis to position the workpiece in the axial direction, and then use an angular grinding wheel that has a pair of mutually perpendicular grinding surfaces to cut the workpiece in a direction that intersects the spindle axis. An angular grinding machine configured to machine the shoulder end face on the workpiece with displacement detection means for detecting displacement in a direction parallel to the grinding wheel axis at the top where the pair of grinding surfaces of the grinding wheel intersect. The relative position between the workpiece and the grinding wheel is corrected in accordance with the magnitude of the displacement detected by the displacement detection means, and the path of the grinding wheel passing through the top of the grinding wheel is set to the workpiece-H. 1. A position correction device for an angular grinding machine, characterized in that the position correction device is provided with a position correction means for passing through a theoretical passing point. (2) The position correction means includes a workpiece table that supports the workpiece and is movable in a direction parallel to the workpiece axis, and a displacement amount of the top detected by the displacement detection means in parallel with the workpiece axis. and a table position correction means for correcting the position of the workpiece table according to the displacement amount converted by the conversion means. A position correction device for an angular grinding machine according to item 1. (3) The position correcting means includes a driving means for axially moving a grinding wheel that supports the grinding wheel, and by operating this driving means, the grinding wheel is moved by an amount of displacement of the top portion detected by the displacement detecting means. 2. The position correction device for an angular grinding machine according to claim 1, further comprising a position correction means for moving the grindstone.