JPH0890408A - Grinding method - Google Patents

Abstract

PURPOSE: To enhance the roundness and grinding accuracy in the grinding method of a cylindrical part of a work of low rigidity without increasing the manufacturing cost. CONSTITUTION: A grinding machine is equipped with a grinding wheel 21 which moves with respect to a work W in two directions of the X direction crossing the Z direction which is parallel to the axis of rotation of the work W. The work W is rough ground through flunge grinding up to the diameter leaving a specified finishing machining allowance as measuring the part Wd of a cylindrical part Wa of the work with a sizing device, after which a center rest device 40 is abutted on the part Wd of the cylindrical part Wa after the midway of rough grinding but before the point of time of contour grinding and the machine coordination system in the X direction is reset based on the output signal of the sizing device at the point of time of completing rough grinding. The cylindrical part Wa and a corner part Wb is given a finishing grind up to the finishing dimensions by contour grinding based on the resetted machine coordination system as leaving the center rest device 40 abutted on the cylindrical part Wa.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cylindrical portion of a workpiece and a cylindrical portion of the workpiece by a grinding machine equipped with a grinding wheel that moves relative to the workpiece in a direction parallel to the axis of the workpiece and a direction intersecting with the axis. The present invention relates to a grinding method for contour-grinding adjacent corners, and particularly to this kind of grinding method suitable for a work having low rigidity.

[0002]

2. Description of the Related Art Conventionally, as a method for grinding a cylindrical workpiece at high speed, a grinding wheel provided with a straight portion parallel to the rotation axis of the workpiece and an inclined taper portion,
First, move the grinding wheel relative to the workpiece in the plunge direction orthogonal to the axis of rotation, perform rough grinding, fine grinding and fine grinding in order to machine one end of the workpiece to the desired finishing diameter, and then machine the grinding wheel. There is a method of grinding the entire outer peripheral surface of the workpiece by moving the workpiece in a direction having a taper portion in a traverse direction parallel to the rotation axis. In such a grinding method, rough grinding can be performed by the taper portion of the grinding wheel during traverse grinding, and then finish grinding can be performed by the straight portion. Therefore, the entire workpiece can be ground by one traverse grinding. You can

When a workpiece W having an arcuate corner portion Wb and a shoulder portion Wc adjacent to a cylindrical portion Wa is ground by such a grinding method, as shown in FIG. Grinding is performed in order of the shoulder portion Wc, the corner portion Wb, and the cylindrical portion Wa by using the grinding wheel G provided with the straight portion Gs parallel to the rotation axis and the inclined taper portion Gt. In this case, the control of the grinding feed amount in the traverse direction is all performed by the coordinates (mechanical coordinates) of the grinding wheel G in the grinder, but the shoulder portion Wc and the corner portion Wb are included in the control of the grinding feed amount in the plunge direction. Is performed in machine coordinates, and the cylindrical portion Wa is performed in the coordinates (workpiece coordinates) of the workpiece when the workpiece W is actually machined in order to emphasize the dimensional accuracy. That is, when the diameter of the left end portion of the cylindrical portion Wa detected by the sizing device 30 reaches the finishing target dimension, the cutting feed in the plunge direction is stopped and the cylindrical portion Wa is ground only by the feed in the traverse direction. It was

However, in the grinding process, the machine coordinates on the grinding machine side and the work piece side coordinate are displaced due to wear of the grinding wheel G, bending of the workpiece W and its supporting portion, thermal displacement, and the like. If the depth of the machine coordinate is larger than the work coordinate due to this deviation, the process moves to traverse grinding before the arcuate shape of the corner Wb is completely formed as shown by the two-dot chain line Wp in FIG. If the machine coordinate cut is smaller than the workpiece coordinate,
As shown by the chain double-dashed line Wn in FIG. 9, even after the arcuate shape of the corner Wb is completely formed, the plunge feed is performed and the step Ws is formed on the workpiece W. There is a problem that the corner Wb cannot be formed.

In order to solve such a problem, the technique of Japanese Patent Application No. 5-68323 (not yet published at the time of the present application), which the applicant previously proposed, is constructed as shown in FIG. Plunge grinding is performed while measuring a part Wd of the cylindrical portion Wa of the object W with a measuring device (sizing device) 30, and it is shown that the diameter of a part Wd of the plunged-ground cylindrical part Wa has reached a target value. When the signal is output from the output measuring device 30, the machine coordinate system in the direction intersecting the rotation axis of the workpiece W of the grinding wheel G is reset based on the output signal of the measuring device 30, and the reset machine coordinate system is set. Based on the above, the shoulder portion Wc, the corner portion Wb, and the cylindrical portion Wa of the workpiece W are continuously contour-ground.

On the other hand, when the cylindrical portion of the work having low rigidity is ground, the grinding is carried out in order to prevent the roundness from being lowered due to the bending of the work and the defective machining due to chattering. Grind another cylindrical part with roundness near the power cylindrical part in the previous process, and contact this steady part with a steady rest that restrains the radial movement of the workpiece. Is being done.

[0007]

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention
When the technology of No. 8323 is applied to the machining of a work piece having a low rigidity, it is necessary to machine another cylindrical portion in the previous step as in the last-mentioned prior art, which increases the number of machining steps. However, especially when such another cylindrical portion needs to be provided only for the steady rest, the material cost also increases, which causes a problem that the manufacturing cost increases.

According to the present invention, such a problem is solved by abutting the steady rest by utilizing the portion which is rough ground by plunge grinding for resetting the machine coordinate system prior to finish grinding by contouring grinding. The purpose is to resolve.

[0009]

SUMMARY OF THE INVENTION A grinding method according to the present invention uses a grinding machine equipped with a grinding wheel that moves relative to a workpiece in a direction parallel to a rotation axis of the workpiece and a direction intersecting the rotation axis. Using a sizing device that measures the outer diameter of the cylinder and a steady rest that abuts the cylindrical outer peripheral surface of the workpiece and restrains the radial movement of the workpiece on this cylindrical outer peripheral surface. This is a grinding method that contours the cylindrical part of the object and the corner adjacent to the cylindrical part with a grinding wheel, and measures a part of the cylindrical part with a sizing device before finishing grinding of the cylindrical part and the corner by contouring grinding. However, rough grinding is performed by plunge grinding to a diameter that leaves a predetermined finishing allowance, and after this rough grinding, before the final grinding by contouring grinding, the steady rest is adjusted to the finished diameter by the cylindrical part. Is cut processed Again steady rest is brought into contact with the cylindrical portion by pressing margin which does not leave from the cylindrical portion,
At the end of rough grinding by plunge grinding, the machine coordinate system in the direction intersecting the workpiece of the grinding wheel is reset based on the output signal of the sizing device at the end of rough grinding, and then the steady rest is applied to the cylindrical part. Finishing grinding is performed on the cylindrical part and corners of the work piece by contouring grinding to the final size based on the machine coordinate system that was reset while still in contact.

In the grinding method according to the present invention, rough grinding comprises rough grinding and subsequent fine grinding, and the steady rest comes into contact with a part of the cylindrical portion when the rough grinding is completed,
The finish grinding may be performed by one contouring grinding.

Further, in the grinding method according to the present invention, rough grinding is made up of rough grinding and subsequent fine grinding, and the steady rest comes into contact with a part of the cylindrical portion at the time when the fine grinding is finished, and the finish grinding is 1 It may be performed by performing contouring grinding once.

[0012]

According to the present invention, first, while measuring a part of the cylindrical portion by a sizing device, rough grinding by plunge grinding is performed to a diameter leaving a predetermined finishing allowance, and after the rough grinding, the contour is ground. Before the final grinding by ring grinding, the steady rest is brought into contact with a part of the cylindrical portion with a pressing margin such that the cylindrical portion does not separate even when the cylindrical portion is ground to the finished diameter. Then, at the end of rough grinding by plunge grinding, the machine coordinate system in the direction intersecting with the workpiece is reset based on the output signal of the sizing device at the end of rough grinding, and then the steady rest is part of the cylindrical part. While still in contact with, the cylindrical part and the corner of the workpiece are finish ground to the final dimension by contouring grinding based on the reset machine coordinate system.

If the rough grinding is made up of rough grinding and subsequent fine grinding, and the steady rest is brought into contact with a part of the cylindrical portion at the end of the rough grinding, the machine coordinate system is reset. Finish grinding is performed by one contouring grinding.

Even if the rough grinding is made up of rough grinding and subsequent fine grinding, and the steady rest is brought into contact with a part of the cylindrical portion at the time when the fine grinding is completed, the machine coordinate system is reset. Finish grinding is performed by one contouring grinding.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A case in which a grinding method according to the present invention is applied to grinding an intermediate journal portion of a crankshaft of an automobile engine will be described below with reference to a first embodiment shown in FIGS.

First, referring to FIGS. 1 and 2, a grinding apparatus used for carrying out the first embodiment will be described. On a work table 12 which is guided and supported on the bed 11 of the grinding machine 10 so as to be movable in the left-right direction (Z direction), a headstock 14 and a tailstock 16 which support a spindle 15 are coaxially opposed to each other in the left-right direction. The workpiece (crank shaft) W is supported at both ends by the spindle 15 and centers 15a, 16a provided on the tailstock 16. The spindle 15 is rotationally driven by a motor provided on the spindle stock 14, and the workpiece W is rotated with the spindle 15 by engaging a drive pin 17 protruding from the spindle 15 at its left end portion. The servomotor 25 provided on the bed 11 is controlled and driven by a drive circuit 53 that operates based on a control pulse given from the numerical controller 50, and is fed to the workpiece table 12 in the Z direction via a feed screw device (not shown). give.
The position of the workpiece table 12 in the Z direction is detected by the encoder and input to the numerical controller 50.

A grindstone base 13 is guided and supported on the bed 11 so as to be movable in a horizontal X direction orthogonal to the Z direction, and a grindstone wheel 21 on which a grindstone wheel 21 is parallel to the main shaft 15 is mounted. Is supported by the motor 22, and is rotationally driven by the motor 22 via the rotation transmission mechanism. The grinding wheel 21 comprises a metal disk-shaped grinding wheel core and a grinding wheel layer in which CBN abrasive grains are bonded together by vitrified bonds. The servomotor 26 provided on the bed 11 is controlled and driven by a drive circuit 54 that operates based on a control pulse given from the numerical controller 50, and the grindstone head 1 is driven via a feed screw device (not shown).
3 is to be fed in the X direction. Grindstone 13 X
The directional position is detected by the encoder and the numerical controller 5
Input to 0. As shown in FIGS. 3 and 4, the grinding wheel 2
An arcuate chamfered portion 21b is formed at both ends of the outer peripheral grinding surface 21a in preparation for traverse grinding.

As shown in FIGS. 1 and 2, a support frame 18 composed of columns 18a and support beams 18b is fixed on the bed 11, and a lifting cylinder is mounted on a bracket 19 fixed near the center of the support beams 18b. The measuring head 31 of the sizing device 30 is attached to an elevating table 35 which is provided so as to be able to elevate and lower a predetermined distance in the vertical Y direction via the device 36 and the pilot bar 37.
Is attached. Mainly as shown in FIG. 2, the measuring head 31 is lifted by a built-in cylinder device.
On the other hand, it has a pair of measuring arms 32 and 33 which can be moved back and forth by a predetermined distance in the X direction and are provided with a pair of contacts 32a and 33a facing each other. The movements of the measuring head 31 in the X and Y directions are controlled by the numerical control device 50 and are normally in the non-actuated position shown by the solid line in FIG. B
In the state of the forward position shown by, each of the contacts 32a, 33
The tip portion of a is engaged with the intermediate portion Wd of the cylindrical portion (intermediate journal portion) Wa, which is the surface to be ground of the workpiece (crank shaft) W being ground, and its outer diameter is continuously measured directly.
The measurement signal (analog signal) is input to the numerical controller 50.

Further, as shown in FIGS. 1 and 2, a steady rest 40 is provided on the work table 12.
A movable base 42 is guided and supported by a base 41 fixed to the work table 12 by a clamp 41a so as to be movable back and forth in the X direction, and a cylinder 47 formed on the movable base 42, a piston 48 fixed to the base 41, and a piston rod 49. The forward / backward moving cylinder device 46 is moved forward / backward by a predetermined distance between the forward position indicated by the solid line and the backward position indicated by the chain double-dashed line C. The movable table 42 has a pair of steady rest arms 43, 44 provided with shoes 43a, 44a, respectively, and each steady rest arm 43, 44 is provided at its tip at the forward position shown by the solid line. The servo motor 45 performs X-direction positioning so that the shoes 43a and 44a come into contact with the cylindrical portion Wa and receive the grinding reaction force applied to the cylindrical portion Wa from the grinding wheel 21. The operation of the steady rest 40 by the servomotor 45 and the advancing / retreating cylinder device 46 is controlled by the numerical controller 50.

As shown in FIG. 1, the numerical controller 50 is connected to an input device 51 such as a keyboard for inputting control data and operation commands, and a memory 52 for storing a grinding program and various data. Numerical control device 50
Is based on a command from the input device 51, a grinding program and data stored in the memory 52, an input signal from the sizing device 30, and the like, the workpiece table 12, the grindstone 13, the sizing device 30, the steady rest device 40, and the like. Control the operation of the grinder 1
It activates 0.

Next, the grinding method according to the first embodiment will be described with reference to the grinding apparatus having the above-mentioned structure, the operating states shown in FIGS. 3 to 5 and the flow chart shown in FIG. 3 and 4 show only the cylindrical portion Wa of the workpiece W and the crank arm portions We on both sides thereof, and other portions are omitted.

When the grinding device starts to operate in response to a command from the input device 51, after resetting various variables to predetermined initial values, the numerical control device 50 causes the headstock 14 and tailstock 16 to operate.
The workpiece W and the grinding wheel 21 supported by are rotated (step 100), and the servomotor 25 is operated so that the positions of the steadying arms 43 and 44 of the steadying device 40 correspond to the positions of the grinding wheel 21. On the work table 1
2 is positioned (step 101). Next, the numerical controller 50 uses the lifting cylinder device 36 and the measuring head 31.
The cylinder device incorporated in the actuator is operated to advance the sizing device 30 to the position indicated by the chain double-dashed line B, and the measuring arms 32,
The tip ends of the contacts 32a, 33a of 33 are engaged with the intermediate portion Wd of the cylindrical portion Wa of the workpiece W (step 102).

Next, the numerical controller 50 uses the servo motor 2
6 is operated so that the grinding surface 21a of the grinding wheel 21 is at the intermediate portion Wd.
After advancing the grindstone 13 forward by a short distance to the point where it abuts on the base, it is advanced by rough grinding feed (step 103), and plunge grinding of the intermediate portion Wd of the cylindrical portion Wa is performed (step 1).
04). This plunge grinding is performed by direct sizing grinding in which a measurement signal (analog signal) of the outer diameter of the intermediate portion Wd obtained from the measuring head 31 is input to the numerical control device 50 every moment. The sizing device 30 may be engaged with the intermediate portion Wd of the cylindrical portion Wa during the rough grinding feed.

When the measurement signal from the sizing device 30 reaches a predetermined rough grinding completion diameter, the numerical control device 50 advances the steady rest device 40 by the advancing / retreating cylinder device 46 to advance the steady rest arms 43, 44 to the tips thereof. The shoes 43a and 44a are brought into contact with the outer peripheral surface of the intermediate portion Wd of the cylindrical portion Wa that has been plunge ground to prevent the workpiece W from steadying (step 10).
5) Then, the grindstone base 13 is continuously advanced by fine grinding feed to perform plunge grinding of the intermediate portion Wd (step 106, FIG. 5).
(a)). The pressing margin of each shoe 43a, 44a of the steady rest 40 with respect to the intermediate portion Wd is a value such that each shoe 43a, 44a does not separate from the intermediate portion Wd even if the intermediate portion Wd is ground to the finishing diameter D. Usually the middle part Wd
The press allowance is set to 0 in the state in which is processed to the finish diameter D. The pressing margin of 0 means that each shoe 43a, even when the intermediate portion Wd is processed to the finishing diameter D.
44a is in contact with the intermediate portion Wd and a slight pressing force is applied.

Intermediate portion Wd detected by the sizing device 30
The outer diameter detection signal is the diameter (D + 2t) (D is the cylindrical portion W
When the finishing diameter of a, t is the finishing allowance) (Fig. 3, Fig. 5 (b)), the numerical control device 50 stops the feed of the wheel head 13, finishes the fine grinding, and resets the machine coordinate system. Then, the steady rest 40 is moved to the middle portion W of the cylindrical portion Wa.
The whetstone base 13 and the sizing device 30 are retracted to a predetermined position while being in contact with d (step 108). The resetting of the machine coordinate system is performed by obtaining the deviation amount between the machine coordinate in the X direction and the work coordinate caused by the deflection of the work W and its supporting portion, thermal displacement, etc. at the end of the fine grinding, and determining the machine coordinate in the X direction. It is corrected according to the workpiece coordinates.
As a result, it is possible to process the cylindrical portion Wa with high accuracy even by indirect sizing using the mechanical coordinate system.

Next, the numerical controller 50 positions the workpiece table 12 at the contouring grinding start position where the workpiece W and the grinding wheel 21 have the relationship shown by the solid line in FIG. 4 (step 109), and the steady rest device 40 continues. Each shoe 43
Contouring by indirect sizing by controlling the position of the grinding wheel head 13 based on a preset machine coordinate system based on a predetermined grinding processing program with a and 44a in contact with the intermediate portion Wd of the cylindrical portion Wa. Grind (Step 1)
10). The position of the grinding wheel 21 during finish grinding of the cylindrical portion Wa by contouring grinding is a position cut in the X direction by 2t with respect to the position of the grinding wheel 21 at the end of precise grinding (when the mechanical coordinate system is reset). (See FIG. 5 (b) and FIG. 5 (c)).

In this contouring grinding, the numerical controller 50 first cuts the grindstone base 13 in the X direction and moves the grindstone 21 with respect to the workpiece W as shown by an arrow F1 in FIG. The finish grinding of the portion Wc is performed, the Z direction feed of the work table 12 and the X direction feed of the grindstone base 13 are combined, and the grinding wheel 21 is moved to the work W with the arrow F.
As shown in FIG. 2, it moves in an arc shape and finishes the corner Wb in an arc shape. In the state where the finish grinding of the corner portion Wb is completed, the left half of the cylindrical portion Wa is finish ground by the grinding wheel 21, and the diameter thereof becomes the finish diameter D. The Z-direction position is set so as to come into contact with the portion. Next, the numerical controller 50 sends the work table 12 in the Z direction (traverse direction), and moves the grinding wheel 21 to the work W by the arrow F.
3, the cylindrical portion Wa is finished and ground to the central portion, and then the whetstone base 13 is once retracted to a predetermined position as shown by an arrow F4. Subsequently, the numerical controller 50 sends the work table 12 in the Z direction, moves the grinding wheel 21 with respect to the work W as shown by arrow F5, and moves to the grinding start position of the shoulder Wc on the right side. Similarly, the workpiece W
On the other hand, the grinding wheel 21 is moved as shown by arrows F6, F7, F8, and the right shoulder portion Wc, the corner portion Wb, and the cylindrical portion Wa are finish ground.

When the contouring grinding as described above is completed, the numerical control device 50 causes the steady rest device 40 and the wheel head 1 to move.
3 is retracted, the rotation of the workpiece W and the grinding wheel 21 is stopped, and the machining of the workpiece W is completed.

As in the present embodiment, the crankshaft W is supported by both the centers 15a and 16a, and the intermediate journal portion W is formed.
When the grinding process of a is performed, the rigidity of the processed portion is small, but in the above-described embodiment, since the radial movement of the intermediate journal portion Wa is restrained by the steady rest device 40, the grinding process is performed, so that chattering etc. It does not occur, and good roundness and processing accuracy can be obtained. In addition, the steady rest 40 is
Since it abuts against the plunge grinding portion for re-setting the machine coordinate system prior to contouring grinding, it is not necessary to previously form a cylindrical portion for abutment of the steady rest 40 in a separate process, thus reducing the manufacturing cost. Can be reduced.

Next, a second embodiment shown in FIGS. 7 and 8 will be described. Since the grinding machine used for carrying out this second embodiment is exactly the same as that shown in FIGS. 1 and 2, its explanation is omitted. Further, the flowchart of the second embodiment shown in FIG. 8 is only partially different from the flowchart of the first embodiment shown in FIG. 6, so this difference will be mainly described.

From step 200 of the flowchart of FIG.
Step 203 is step 100 to step 10 in FIG.
Same as 3. In step 204, step 1 in FIG.
The rough grinding and the fine grinding in 04 and step 106 are continuously performed without interposing step 105 in the middle. When the detection signal of the outer diameter of the intermediate portion Wd detected by the sizing device 30 reaches (D + 2t) in diameter (FIG. 7 (a)), the numerical control device 50 stops the feed of the wheel head 13 and performs the fine grinding. Upon completion, the machine coordinate system is reset (step 205), and the grindstone base 13 and the sizing device 30 are retracted to predetermined positions (step 206). The resetting of the machine coordinate system is performed in the same manner as in the case of the first embodiment.

Next, the numerical controller 50 advances the steady rest 40 to move the shoes 43a, 44a at the tips of the steady rests 43, 44 into a cylindrical portion Wa which has been plunge ground.
The workpiece W is held steady by contacting the outer peripheral surface of the intermediate portion Wd (step 207, FIG. 7B). This steady rest is performed in the same manner as step 105 in FIG.
The pressing margin of the intermediate portion Wd is the finishing diameter D as in the first embodiment.
Although the shoes 43a and 44a do not separate from the intermediate portion Wd even if they are ground up to, the pushing amount Δ of the steady rest 40 with respect to the position of the cylindrical portion Wa at the time of finishing the fine grinding.
Is determined in consideration of the amount of bending of the workpiece W in the cylindrical portion Wa at the end of fine grinding by plunge grinding. This deflection amount is obtained from known grinding data of the same workpiece, and the pushing margin Δ is, for example, a value obtained by adding the finishing machining allowance t to this deflection amount.

Next, the numerical controller 50 proceeds to step 20.
Through 8 to 210, the workpiece table 12 is positioned, contouring grinding is performed, and when the grinding is completed, the machining of the workpiece W is stopped. The steps 208 to 210 are almost the same as the steps 109 to 111 in FIG. 8, but the position of the grinding wheel 21 at the time of finish grinding of the cylindrical portion Wa by contouring grinding is set at the end of the fine grinding (machine coordinate system re-grinding). (Δ-t) for the position of the grinding wheel 21 (when set)
Only the position on the front side in the X direction (see FIGS. 7 (b) and 7 (c)).

In each of the above embodiments, the contouring grinding is
As shown in FIG. 4, the shoulder portion Wc on the left side and the cylindrical portion Wa
The grinding wheel 21 is moved backward after grinding the left half of the above, and the right half of the shoulder portion Wc and the cylindrical portion Wa is ground, but the entire cylindrical portion Wa is finished by one traverse grinding, and the right cylindrical portion Wa may be finished at the end of this traverse grinding and when the grinding wheel 21 is retracted.

In each of the above-described embodiments, the finishing grinding is performed by one contouring grinding, but the contouring grinding by the indirect sizing after the plunge grinding is divided into a plurality of times to finish the final contouring grinding. May be set. In this case, the steady rest 40 may be brought into contact with a part Wd of the cylindrical portion Wa to perform grinding only in the last contouring grinding.

In the relation to claim 1, the combination of the rough grinding and the fine grinding in each of the above embodiments corresponds to the rough grinding by plunge grinding performed before the finish grinding by contouring grinding.

[0037]

As described above, according to the present invention, at the time of finish grinding by contouring grinding, the workpiece is ground in a state in which the movement in the radial direction is restricted by the steady rest, so that a good true result is obtained. Roundness and processing accuracy can be obtained.
Further, since the steady rest is brought into contact with the rough ground portion by plunge grinding performed for resetting the machine coordinate system prior to contouring grinding, a cylindrical portion for contacting the steady rest is formed in advance in a separate process. do not have to. Therefore, the manufacturing cost does not increase due to the increase in the number of processing steps.

If the rough grinding is made up of rough grinding followed by fine grinding, and the steady rest is brought into contact with a part of the cylindrical portion at the end of the rough grinding, the finish grinding is performed once for the contour. Since the ring grinding is performed, the manufacturing cost can be further reduced.

Even if the rough grinding is made up of rough grinding and subsequent fine grinding, and the steady rest is brought into contact with a part of the cylindrical portion at the end of the fine grinding, the finish grinding is performed only once. Since the ring grinding is performed, the manufacturing cost can be further reduced.

[Brief description of drawings]

FIG. 1 is a diagram showing an overall configuration of a grinding apparatus used for carrying out a grinding method according to the present invention.

FIG. 2 is a partial side view showing a main part of the grinding device shown in FIG.

FIG. 3 is an explanatory diagram showing a state at the end of precise grinding by plunge grinding in the first embodiment of the grinding method according to the present invention.

FIG. 4 is an explanatory diagram showing a finish grinding state by contouring grinding according to the first embodiment of the present invention.

FIG. 5 is an explanatory diagram showing a grinding state in each stage of the first embodiment of the present invention.

FIG. 6 is a flowchart showing the operation of the first embodiment of the present invention.

FIG. 7 is an explanatory view showing a grinding state in each stage of the second embodiment of the grinding method according to the present invention.

FIG. 8 is a flowchart showing the operation of the second embodiment of the present invention.

FIG. 9 is an explanatory diagram of a first conventional technique.

FIG. 10 is an explanatory diagram of a second conventional technique. 10 ... Grinder, 21 ... Grinding wheel, 30 ... Sizing device, 40 ...
Steady rest device, W ... Workpiece, Wa ... Cylindrical part, Wb ... Corner part, Wd ... Part (intermediate part).

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Mamoru Katsuta 1-1, Asahi-cho, Kariya city, Aichi prefecture Toyota Koki Co., Ltd.

Claims (3)

[Claims] 1. An outer diameter dimension of a cylindrical portion of a workpiece is measured by a grinder provided with a grinding wheel that moves relative to the workpiece in a direction parallel to a rotation axis of the workpiece and a direction intersecting with the rotation axis. Using the sizing device and a steady rest that abuts the cylindrical outer peripheral surface of the workpiece and restrains the radial movement of the workpiece on the cylindrical outer peripheral surface, In a grinding method of contouring a corner adjacent to a portion by the grinding wheel, a predetermined portion of the cylindrical portion is measured by the sizing device prior to finish grinding of the cylindrical portion and the corner by contouring grinding. Rough grinding is performed by plunge grinding to a diameter that leaves the finishing allowance, and the cylindrical portion finishes the steady rest after the rough grinding and before the finish grinding by contouring grinding. Even if it is ground to the diameter, the steady rest comes into contact with the part of the cylindrical portion with a pressing margin so as not to separate from the part of the cylindrical portion, and at the end of the rough grinding by the plunge grinding, the grindstone. The machine coordinate system of the vehicle in the direction intersecting with the workpiece is reset based on the output signal of the sizing device at the end of the rough grinding, and then the steady rest is brought into contact with a part of the cylindrical portion. A grinding method, characterized in that the cylindrical portion and the corner portion of the workpiece are ground by contouring grinding to a finishing dimension based on the reset machine coordinate system. 2. The rough grinding comprises rough grinding and subsequent fine grinding, the steady rest contacts a part of the cylindrical portion at the time when the rough grinding is completed, and the finish grinding is performed once. The grinding method according to claim 1, which is performed by ring grinding. 3. The rough grinding comprises rough grinding and subsequent fine grinding, the steady rest comes into contact with a part of the cylindrical portion when the fine grinding is completed, and the finish grinding is performed once. The grinding method according to claim 1, which is performed by ring grinding.