JP2009285748A - Grinding wheel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a grindstone capable of continuously performing two grinding processes with the same apparatus without correcting a grinding tip position.
A grindstone 10 is disposed on a part of the outer peripheral surface of a wheel 11 in place of an abrasive grain layer 12, and protrudes outside the abrasive grain layer when the wheel rotates at a low speed or stops rotating, and when the wheel rotates at a high speed. A finishing wrapping means 20 is provided which is retracted inside the abrasive grain layer. Since the wheel is rotated at a high speed to finish grinding with the abrasive layer, and then the wheel is rotated at a low speed to finish lapping with the finishing wrapping means, it is necessary to adjust the tool tip positional relationship between the abrasive layer and the finishing wrapping means. In addition, grinding finishing and finishing lapping can be performed continuously with the same apparatus.
[Selection] Figure 1

Description

  The present invention relates to a grindstone having an abrasive layer formed on the outer peripheral surface of a wheel, and more particularly to a multifunctional grindstone capable of grinding finishing and finishing lapping.

The grindstone described in Patent Document 1 includes a ring-shaped grindstone fixing substrate made of cast iron and having a mounting hole attached to a rotating shaft at the center, and a grindstone member fixed to the outer peripheral surface of the grindstone fixing substrate. Yes. And a grindstone member is formed from the 1st grindstone member and the 2nd grindstone member which are divided | segmented into the axial width direction and are arrange | positioned in parallel. The processing surface consisting of the first grindstone member and the second grindstone member has a different structure, the first grindstone member is for rough grinding, the first processing surface has relatively large abrasive grains, and the second grindstone member Is for finish grinding, and the second processed surface has relatively small abrasive grains. According to the grindstone having such a configuration, rough grinding and finish grinding can be performed continuously with the same apparatus, the processing time can be shortened, and the processing space can be minimized.
Japanese Patent Laying-Open No. 2004-90117 (paragraphs [0013] and [0022], FIG. 2)

  In what is described in Patent Document 1, since the first grindstone member and the second grindstone member are divided in the axial width direction on the grindstone fixing substrate and arranged in parallel, rough grinding and finish grinding are performed with the same apparatus. To carry out continuously, it is necessary to frequently correct the grinding tip position.

  This invention is providing the grindstone which can perform two grinding processes continuously with the same apparatus, without correcting the grinding | polishing front-end | tip position.

  In order to solve the above-mentioned problem, the structural feature of the invention according to claim 1 is that, in a grindstone in which an abrasive layer is formed on the outer peripheral surface of the wheel, the abrasive layer is formed on a part of the outer peripheral surface of the wheel. Instead, it is provided with a finishing wrapping means that protrudes outside the outer periphery of the abrasive layer when the wheel rotates at a low speed or stops rotating, and retracts inside the outer periphery of the abrasive layer when the wheel rotates at a high speed, The wheel is rotated at a high speed and ground by the abrasive layer, and the wheel is rotated at a low speed and finished lapping is performed by the finishing lapping means.

  According to a second aspect of the present invention, in the first aspect, the finishing wrapping means includes a wrap film stretched on a part of an outer peripheral surface of the wheel, and a wrap film incorporated in the wheel. Film pressing means having at one end a pressing portion capable of pressing the film from the inner peripheral surface side, a heavy object fixed to the other end of the film pressing means, and an elastic member fixed to the wheel and the film pressing means The wrap film is pressed by the film pressing means by the elastic force of the elastic member when the wheel is rotated at a low speed or when the rotation is stopped, so that the wheel protrudes outward from the outer periphery of the abrasive layer, At the time of rotation, the film pressing means is separated from the wrap film by centrifugal force acting on the heavy object, and the wrap film is separated from the abrasive layer. Center of gravity of the wheel retraction inner than a peripheral surface is that the upper rotating shaft.

The structural feature of the invention described in claim 3 is that, in claim 2, the finishing wrapping means is incorporated in the wheel, and a first roll for winding the unused wrap film and the used wrap. A second roll for winding the film.
According to a fourth aspect of the present invention, there is provided a structural feature according to any one of the first to third aspects, wherein a plurality of the finishing wrapping means are provided, and the center of gravity of the entire grindstone is positioned on the rotation axis during high-speed rotation. It is formed.

A structural feature of the invention according to claim 5 is that, in any one of claims 2 to 4, the film pressing means is configured to contact and fix the wheel during high-speed rotation of the wheel.
A structural feature of the invention according to claim 6 is that, in any one of claims 2 to 5, the film pressing means has a shaft structure.

  According to the first aspect of the present invention, when the wheel having the abrasive layer formed on the outer peripheral surface is rotated at a low speed or stopped, the wheel protrudes outside the outer periphery of the abrasive layer, and when the wheel rotates at a high speed, Since the finishing wrapping means that retracts to the inside of the outer periphery is arranged in place of the abrasive layer on a part of the outer peripheral surface of the wheel, the wheel is ground only by the abrasive layer by rotating the wheel at a high speed. By rotating at a low speed, the finishing lapping can be performed only by the finishing wrapping means. Therefore, there is no need to adjust the tool tip positional relationship between the abrasive layer and the finishing lapping means, and the grinding process and the finishing lapping process can be performed continuously with the same apparatus.

  According to the second aspect of the present invention, the wrap film is stretched around a part of the outer peripheral surface of the wheel, and has a pressing portion that can press the wrap film from the inner peripheral surface side at one end and a heavy article at the other end. The film pressing means to which the wheel is fixed is built in the wheel, and the elastic member is interposed between the wheel and the film pressing means and fixed to each other. The wrap film is pressed by the film pressing means by force and protrudes outside the outer periphery of the abrasive layer, and the film pressing means is separated from the wrap film by centrifugal force acting on the heavy load when the wheel rotates at high speed. Can be retracted inside the outer periphery of the abrasive layer. Therefore, it is possible to perform grinding with only the abrasive layer by rotating the wheel at a high speed, and finish lapping with only the finishing wrapping means by rotating the wheel at a low speed.

According to the third aspect of the invention, the wheel includes the first roll around which the unused wrap film is wound and the second roll around which the used wrap film is wound. The wrap film can be easily stretched on a part of the outer peripheral surface of the wheel, and the wrap film in the pressing part can be easily changed to an unused part after use. Finish lapping can be performed.
According to the invention of claim 4, since the plurality of finishing wrapping means are formed so that the center of gravity of the entire grindstone is located on the rotation axis, it is possible to suppress the rotational vibration amplitude especially during high-speed rotation of the grindstone. High-precision grinding and finishing can be performed. It should be noted that there is no particular problem when the grindstone rotates at low speed because the rotational vibration amplitude is small.

According to the invention of claim 5, since the film pressing means is in contact with and fixed to the wheel during high-speed rotation of the wheel, it is possible to suppress the rotational vibration amplitude especially during high-speed rotation of the grindstone, and high accuracy. Can be finished.
According to the sixth aspect of the present invention, since the film pressing means has a shaft structure, the wrap film is pressed / pressed only by the movement of the pressing means within the cylindrical storage portion provided from the outer peripheral surface of the wheel to the inside. It can be canceled.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
A grindstone 10 shown in FIG. 1 is a grindstone for grinding an outer peripheral cylindrical surface of a workpiece, which can be subjected to finish lapping following grinding finish processing. On the grindstone 10, fan-shaped abrasive grain layers 12 that perform grinding finish processing are formed at two opposing positions on the outer peripheral surface of the hollow disc-shaped metal wheel 11, respectively. Then, two sets of finish lapping means 20 for performing finish lapping are incorporated in the wheel 11 so as to be able to protrude from two outer peripheral surfaces of the wheel 11 on which the abrasive grain layer 12 is not formed. The wheel 11 may be formed of CFRP (Carbon Fiber Reinforced Plastic).

  The abrasive grain layer 12 is formed in a fan shape by attaching a plurality of arc-shaped grindstone chips 12 a at two opposing positions on the outer peripheral surface of the wheel 11. The two abrasive grain layers 12 are provided point-symmetrically with respect to the grindstone rotating shaft 10a. The grindstone tip 12a is formed by bonding CBN (Cubic Boron Nitride) abrasive grains, which are superabrasive grains, with vitrified bonds, for example. The finishing wrapping means 20 includes a wrap film 21, a film pressing means 22, a weight 23, an elastic member 24, first and second rolls 25 and 26, and a roll lock 27.

  The wrap film 21 is formed in a tape shape with lapping abrasive grains fixed on the surface, the unused wrap film 21 is wound around the first roll 25, and the used wrap film 21 is applied to the second roll 26. It is designed to be wound. The film pressing means 22 includes a pressing portion 28 that presses the wrap film 21 and a shaft 29 with the pressing portion 28 attached to one end. The heavy object 23 is a metal body and is fixed to the other end of the shaft 29. The elastic member 24 is a tension coil spring, and is fitted into the shaft 29 so that one end is fixed to the heavy object 23.

  The wheel 11 is provided with two cylindrical wrapping means storage portions 11a extending inward from two outer peripheral surfaces of the wheel 11 on which the abrasive grain layer 12 is not formed. The two wrapping means storage portions 11a are provided point-symmetrically with respect to the grindstone rotating shaft 10a. A film pressing means 22 is inserted into the wrapping means storage portion 11a from the heavy load 23 side. The other end of the elastic member 24 is fixed to the opening edge of the wrapping means storage portion 11a. The wrapping means storage portion 11a has an opening size that allows the heavy object 23 to move smoothly without play, and when the end surface of the heavy object 23 comes into contact with the bottom surface of the wrapping means storage portion 11a as shown in FIG. 28 is formed with a length that is positioned and fixed to the opening edge of the wrapping means storage portion 11a. The pressing unit 28 may be positioned and fixed by bringing the weight 23 into contact with the side surface of the wrapping means storage portion 11a as a tapered surface that narrows toward the bottom surface.

  Furthermore, the wheel 11 is provided with roll storage portions 11b and 11c on both sides of the two wrapping means storage portions 11a. One set of the first roll 25 and the second roll 26 is rotatably supported on the left side of the roll storage portion 11b and the roll storage portion 11c, respectively, and the other set of the first roll 25 and the second roll 26 is The roll storage part 11c and the roll storage part 11b are rotatably supported on the right side of the figure. A roll lock 27 that locks the rotation of the first roll 25 is disposed in the vicinity of the first roll 25. The two sets of the first and second rolls 25 and 26 and the roll lock 27 are provided symmetrically with respect to the grindstone rotating shaft 10a.

  The 1st roll 25 has a structure which supplies the unused wrap film 21 by rotating using a tool from the outside. The second roll 26 has a wound spring structure that applies tension to the used wrap film 21 in the winding direction. The roll lock 27 has a structure capable of fixing / releasing the rotation of the first roll 25 by rotating with a tool from the outside. The wrap film 21 drawn from the first roll 25 is wound around the second roll 26 through the outer periphery of the pressing portion 28 of the film pressing means 22 protruding from the opening of the wrapping means accommodating portion 11a. . At the time of processing, the grindstone 10 rotates only in the direction of the arrow a shown in the figure, and the rotation of the first roll 25 is fixed by the roll lock 27. Can do. Furthermore, since tension is applied in the winding direction by the second roll 26, loosening of the wrap film 21 at the pressing portion 28 of the film pressing means 22 can be suppressed.

  In such a configuration, when the grindstone 10 is rotating at a low speed at which rotation can be stopped or finished lapping, the elastic force of the elastic member 24 is greater than the centrifugal force acting on the heavy object 23 as shown in FIG. The tip of the pressing part 28 protrudes outward from the outer periphery of the abrasive grain layer 12. Note that the tension in the winding direction by the second roll 26 is set to such an extent that the extrusion of the wrap film 21 at this time is not hindered. On the other hand, when the grindstone 10 is rotating at a high speed capable of grinding and finishing, the centrifugal force acting on the heavy load 23 is set to be larger than the elastic force of the elastic member 24 as shown in FIG. And the front-end | tip of the press part 28 is retracted inside the outer periphery of the abrasive grain layer 12. FIG. At this time, the end face of the heavy load 23 abuts against the bottom surface of the wrapping means storage portion 11a, and the pressing portion 28 is positioned and fixed to the opening edge of the wrapping means storage portion 11a. Is provided point-symmetrically with respect to the grindstone rotating shaft 10a, so that no rotational vibration amplitude is generated particularly when the grindstone 10 rotates at high speed.

FIG. 3 is a plan view showing the entire grinding machine in which the above-described grindstone 10 can be used.
A table 32 is guided and supported on the bed 31 of the grinding machine 30 so as to be movable in the horizontal Z-axis direction. A spindle stock 33 and a tailstock 34 are arranged on the table 32 so as to face each other. The spindle stock 33 is provided with a chuck 35 for gripping one end of the workpiece W, and the tailstock 34 is provided with a center 36 for supporting the other end of the workpiece W. The workpiece W is supported at both ends by a chuck 35 and a center 36 so as to be rotated around an axis parallel to the Z-axis direction, and is rotated by the chuck 35. On the bed 31, a grindstone base 37 is guided and supported so as to be movable in a horizontal X-axis direction orthogonal to the Z-axis direction. The grindstone 10 supports the grindstone 10 so as to be rotatable around an axis parallel to the Z-axis direction. The grindstone 10 is rotated by a grindstone drive motor 60 via a belt transmission mechanism. Further, an AE sensor 38 that detects contact with the workpiece W is attached to the grindstone table 37.

  A numerical control device 40 for controlling the grinding machine 30 mainly comprises a central processing unit 41, a memory 42 for storing various control values and programs, and interfaces 43 and 44. The memory 42 stores various data necessary for executing a grinding program, a grinding cycle, and the like. Various data are input to and output from the numerical control device 40 via interfaces 43 and 44. The input / output device 45 includes a keyboard for inputting data and a display device such as a CRT for displaying data. Further, a detection signal from the AE sensor 38 is input to the numerical control device 40 via the amplifier 46.

  The numerical control device 40 is adapted to give a drive signal to an X-axis servo motor 51 that moves the grinding wheel base 37 in the X-axis direction via the X-axis motor drive unit 50, and is attached to the X-axis servo motor 51. The encoder 52 is configured to send the rotational position of the X-axis servomotor 51, that is, the position of the grindstone table 37 to the X-axis motor drive unit 50 and the numerical controller 40. The numerical control device 40 is adapted to give a drive signal to a Z-axis servomotor 55 that moves the table 32 in the Z-axis direction via the Z-axis motor drive unit 54, and is attached to the Z-axis servomotor 55. The encoder 56 is configured to send the rotational position of the Z-axis servomotor 55, that is, the position of the table 32 to the Z-axis motor drive unit 54 and the numerical controller 40. The numerical controller 40 drives the servo motors 51 and 55 according to the deviation between the target position command of the NC program stored in the memory 42 and the current position signal from the encoders 52 and 56, respectively. Positioning control is performed at each target position.

  A case where the outer peripheral cylindrical surface of the workpiece W is ground and finished by the grindstone 10 using the grinding machine 30 having such a configuration will be described. The operator checks whether or not the portion of the wrap film 21 pressed by the pressing portion 28 of the film pressing means 22 can be used. When the wrap film 21 cannot be used, the roll lock 27 is rotated from the outside using a tool to release the rotation of the first roll 25. And the unused wrap film 21 wound by rotating the 1st roll 25 from the outside using a tool is sent out. At this time, the second roll 26 automatically winds the used wrap film 21 and applies tension in the winding direction. Then, the roll lock 27 is rotated from the outside using a tool to fix the rotation of the first roll 25.

  The numerical controller 40 drives the Z-axis and X-axis servomotors 55 and 51 to control the movement of the table 32 and the grindstone table 37 in the Z-axis direction and the X-axis direction, and the grindstone 10 corresponds to one end of the workpiece W. Position to position. Next, the grindstone 10 is driven to rotate at a high speed so that the lap film 21 is retracted inside the outer periphery of the abrasive grain layer 12 together with the pressing portion 28 and the X-axis servo motor 51 is driven to move the grindstone base 37 toward the table 32 side. To move forward. When the AE sensor 38 detects that the abrasive grain layer 12 of the grindstone 10 has come into contact with the outer peripheral cylindrical surface of the workpiece W, the contact detection position is stored, and the X-axis servo motor 51 is reversely driven to place the grindstone base 37 on the table 32. Release from once. Then, the Z-axis servomotor 55 is driven to move and control the table 32 and the grindstone table 37 in the Z-axis direction, and the grindstone 10 is positioned at a position corresponding to a position slightly deviated from one end of the workpiece W. The X-axis servo motor 51 is driven to advance the grindstone table 37 from the contact detection position by the amount of the grinding finishing cut stored in the memory 42, and then the Z-axis servo motor 55 is driven to place the table 12 in place. Traverse quantitatively. Thereby, the grinding finish processing of the outer peripheral cylindrical surface of the workpiece W is completed by the abrasive grain layer 12 of the grindstone 10.

  Subsequently, the numerical control device 40 drives the Z-axis and X-axis servomotors 55 and 51 to control the movement of the table 32 and the grindstone table 37 in the Z-axis direction and the X-axis direction, and moves the grindstone 10 to one end of the workpiece W. Position it at a position corresponding to. Next, the grindstone 10 is driven to rotate at a low speed to cause the lap film 21 to protrude outside the outer periphery of the abrasive grain layer 12 together with the pressing portion 28, and the Z-axis servomotor 55 is driven to move the table 32 and the grindstone base 37 to the Z-axis. The movement control is performed in the direction, and the grindstone 10 is positioned at a position corresponding to a position slightly deviated from one end of the workpiece W. The X-axis servo motor 51 is driven to advance the wheel head 37 to a position slightly away from the grinding finish position stored in the memory 42, and then the Z-axis servo motor 55 is driven to traverse the table 12 by a predetermined amount. To do. Thereby, the finishing lapping of the outer peripheral cylindrical surface of the workpiece W is completed with the lapping film 21 of the grindstone 10.

  In the above-described embodiment, two sets of finishing wrapping means 20 are arranged on the wheel 11, but three or more sets may be arranged symmetrically with respect to the grindstone rotating shaft 10a within the range allowed by the space of the wheel 11. Further, although the tension member spring is used as the elastic member 24, a compression coil spring, a torsion coil spring, rubber or the like may be used. When a compression coil spring is used, a compression coil spring storage portion having a step on the bottom surface of the wrapping means storage portion 11a is provided. As a result, the end surface of the heavy object 23 abuts against the bottom surface of the wrapping means storage portion 11a without the compression coil spring being in the way, and the pressing portion 28 can be positioned and fixed to the opening edge of the wrapping means storage portion 11a.

It is sectional drawing which shows embodiment of the grindstone in the state in which the finishing lapping means protruded outside the abrasive grain layer. It is sectional drawing which shows embodiment of the grindstone in the state where the finishing lapping means retracted inside the abrasive grain layer. It is a top view which shows the whole grinding machine which can use the grindstone of embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Grinding wheel, 10a ... Wheel rotating shaft, 11 ... Wheel, 11a ... Lapping means storage part, 11b, 11c ... Roll storage part, 12 ... Abrasive layer, 12a ... Grinding wheel chip, 20 ... Finishing lapping means, 21 ... Lapping Film, 22 ... film pressing means, 23 ... heavy load, 24 ... elastic member, 25 ... first roll, 26 ... second roll, 27 ... roll lock, 28 ... pressing portion, 29 ... shaft, 30 ... grinding machine.

Claims (6)

In the grindstone in which an abrasive layer is formed on the outer peripheral surface of the wheel,
The wheel is disposed on a part of the outer peripheral surface of the wheel in place of the abrasive layer, protrudes outside the outer periphery of the abrasive layer when the wheel rotates at a low speed or stops rotating, and the abrasive grain when the wheel rotates at a high speed It has a finishing wrapping means that retracts inside the outer periphery of the layer,
A grindstone characterized in that the wheel is rotated at a high speed for grinding with the abrasive layer, and the wheel is rotated at a low speed for finishing lapping by the finishing lapping means.   2. The finishing wrapping means according to claim 1, wherein the finishing wrapping means includes a wrap film stretched on a part of the outer peripheral surface of the wheel, and a pressing portion built in the wheel and capable of pressing the wrap film from the inner peripheral surface side. A film pressing means, a heavy object fixed to the other end of the film pressing means, and an elastic member fixed to the wheel and the film pressing means. The wrap film is pressed by the film pressing means by the elastic force of the elastic member to protrude outward from the outer periphery of the abrasive grain layer, and the film is pressed by centrifugal force acting on the heavy object when the wheel rotates at high speed. The means is separated from the wrap film, and the wrap film is drawn inward from the outer peripheral surface of the abrasive layer to the wheel. Grindstone center of gravity is characterized by comprising an upper rotary shaft.   In Claim 2, The said finish lapping means is equipped with the 1st roll which is built in the said wheel and winds the said unused wrap film, and the 2nd roll which winds this used wrap film. A characteristic grinding wheel.   4. The grindstone according to claim 1, wherein a plurality of the finishing wrapping means are provided, and the center of gravity of the entire grindstone is located on the rotation axis during high-speed rotation.   5. The grindstone according to claim 2, wherein the film pressing means is configured to contact and fix the wheel when the wheel rotates at a high speed.   6. The grindstone according to claim 2, wherein the film pressing means has a shaft structure.

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