JP2001054871A - Elastic offset grinding wheel and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an elastic offset grinding wheel having a flexibility and is adequate for a curved surface grinding, both flexibility and the grinding speed a long service life, generating little noise and vibration, with an excellent grinding speed. SOLUTION: This offset grinding wheel 2 consists of compression molding an abrasive grain compound made by blending a binder and the like with abrasive grains, and baking it. In such an offset grinding wheel, the abrasive grains and an elastic power such as a powder rubber are blended in at least the abrasive grain compound to form the surface of a grinding part 1, while an elastic powder such as a powder rubber is combined to the abrasive grains or a solid powder to be a reinforcement agent of the same level with the abrasive grains, at the blending ratio larger than the abrasive grain compound to form the grinding part, to the abrasive grain compound to form an offset part 4 at the center part of the offset grinding wheel 2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an offset grinding wheel, and more particularly, to a method in which an elastic body such as rubber is mixed with abrasive grains.
The present invention relates to an offset grinding wheel having elasticity and a method for manufacturing the same.

[0002]

2. Description of the Related Art A conventional offset grindstone is manufactured by compression-molding abrasive grains made of silicon carbide, gold sand or the like into a disk shape together with a binder, and then heat-treating the binder to form a single piece. Since it is large and has little flexibility, it is not suitable for grinding and polishing of a curved surface, and a sanding wheel made of a disk-shaped sandpaper is used for polishing of a curved surface.

Further, in order to give a little flexibility to a conventional offset wheel having a large rigidity, the offset wheel is formed thin and then forcibly bent to form a large number of cracks in a disk portion used for grinding. Attempts have been made to provide flexibility.

Further, the present inventor has disclosed in Japanese Patent Application No. 6-280062 (Japanese Patent Application Laid-Open No. Hei 8-118240) a compression molding of an abrasive composition obtained by compounding abrasive grains with a binder or the like into a disk shape. A grind wheel made by firing, having a wave-shaped unevenness on one surface of the grind wheel, and the wave shape has a large number of wave front lines extending in a substantially radial direction from a center portion of the grind wheel to an outer peripheral portion; An offset grinding wheel having a wavy shape in which the surface of the grinding wheel has a wavy shape in a cross section along a concentric circle concentric with the center of the grinding wheel has been disclosed.

[0005] Further, the present inventor has disclosed in Japanese Patent Application No. 9-338200.
Japanese Patent Application Laid-Open No. 11-156729 discloses a grinding wheel provided with an elastic superabrasive grinding wheel in which an elastic material powder such as rubber is blended with an abrasive compound constituting an offset grinding wheel.

[0006]

The above-mentioned conventional offset grinding wheel has a high rigidity and is not suitable for grinding a curved surface. When grinding a flat surface, only the circumferential portion of the offset grinding wheel is applied to the surface of the workpiece. Therefore, it is difficult to uniformly grind the plane. Furthermore, when grinding with a conventional rigid offset wheel, the noise and vibration during the work are extremely large, the work environment is poor, noise pollution occurs around the work place, and the vibration causes white wax to the worker. There is a risk of causing health damage such as illness.

[0007] Even if an offset grinding wheel having a large rigidity is forcibly bent to generate cracks on the disk portion to give flexibility, it is difficult to give sufficient flexibility to grind a curved surface. Yes, in order to provide flexibility by cracking, it is necessary to reduce the number of glass fiber cloths for reinforcement buried inside the offset grinding wheel to at most one or two, and the cracked offset grinding wheel is used during use. It is easy to chip, has low durability, and the chips of the chip are scattered, which is extremely dangerous.

A conventional sanding wheel using a disk-shaped sandpaper can grind a curved surface, but the sandpaper wears out in a short period of time and has a short life, and requires frequent replacement, resulting in poor work efficiency. In addition, there is a disadvantage that the grinding cost increases.

The present inventors have already disclosed in Japanese Patent Application No. 9-338200 (Japanese Patent Application Laid-Open No. 11-156729) an elastic compound such as rubber to an abrasive compound constituting an offset grinding wheel provided with a superabrasive wheel. In the case of an offset grinding wheel with elasticity that mixes powder, the powdered rubber and the like are blended uniformly throughout the offset grinding wheel. Both were exhibited, and it was possible to achieve both the flexibility of the grinding wheel and the grinding speed. However, if the super-abrasive grindstone is not used and powder rubber is simply blended with ordinary abrasive grains and uniformly distributed throughout the grinding wheel, the rigidity and grinding force required for the grinding section and the powder rubber blending However, if the amount of powdered rubber or the like is excessively increased in order to increase the flexibility, the grinding speed decreases.

[0010] Accordingly, an object of the present invention is to provide an elastic grinding wheel having flexibility and suitable for curved surface grinding. It is a further object of the present invention to provide an elastic offset grinding wheel which has both flexibility and a grinding speed, has a long service life, generates little noise and vibration, and has a high grinding speed.

[0011]

In order to achieve the above object,
As a result of repeated studies, the present inventor has found that, in an offset grinding wheel using abrasive grains of silicon carbide or the like used in a normal grinding wheel, a part or all of the grinding wheel using abrasive grains mixed with powder rubber. By molding a rubber, it is possible to obtain a flexible offset grinding wheel with rubber, the flexible offset grinding wheel with rubber is suitable for curved surface grinding, powder by each part of the offset grinding wheel By providing a difference in the amount of rubber compounded, the flexibility of the entire grinding wheel and the grinding speed of the ground surface can be compatible, and the flexible offset grinding wheel containing rubber has a very long life, It has been found that by forming irregularities on the grinding surface of a car, the grinding speed can be increased. In addition, the offset grinding wheel containing rubber has extremely low noise and vibration generated during the grinding operation, and there is no danger of chipping of the grinding wheel during the grinding operation and fragments of the grinding wheel being scattered. Therefore, they found that they were extremely suitable for surface grinding, and completed the present invention.

That is, in an offset grinding wheel formed by compression molding and baking an abrasive composition obtained by blending a binder or the like with abrasive grains, the abrasive composition in which at least the surface of the grinding portion is formed is added to the abrasive composition. Along with compounding the elastic powder such as granules and powder rubber,
The abrasive composition for forming the offset portion at the center of the offset grinding wheel includes an abrasive powder or an elastic powder such as powdered rubber as a solid powder which is a reinforcing agent equivalent to the abrasive, and a grinding agent for forming the ground portion. The gist of the present invention is an elastic offset grinding wheel characterized by being blended at a larger blending ratio than the grain blend.

Another aspect of the present invention is an abrasive powder in which a binder is mixed between an upper mold and a lower mold in a cylinder installed with a disc-shaped lower mold fitted to the bottom and the axis set to be vertical. In a method of manufacturing a grinding wheel in which a disc-shaped product is heated and fired after pressing into a disc by pressing at a high pressure with an abrasive composition comprising the same, a peripheral portion of the upper surface of the lower mold in the cylinder A part of the grinding part is formed to a certain thickness, and an abrasive compound formed by mixing elastic powder such as powder rubber with abrasive particles is deposited to form an abrasive layer, and an offset of the center of the upper surface of the lower mold is formed. The elastic powder such as powdered rubber or the like is used as a reinforcing material equivalent to abrasive grains or abrasive grains to a certain thickness in the part where the part is formed. Arrange the abrasive composition blended in, place a glass fiber reinforced cloth thereon, and further on the abrasive composition forming the grinding portion, An abrasive compound containing an elastic powder such as powdered rubber forming a base portion formed on the back surface of the shaved portion is arranged, and the elastic powder is further ground on a portion forming an offset portion in the center of the mold. SUMMARY OF THE INVENTION A gist of the present invention is a method for manufacturing an elastic offset grinding wheel, characterized by arranging an abrasive composition more than an abrasive composition in a part, and integrally press-molding the whole.

Still another aspect of the present invention is a method of manufacturing an offset grinding wheel, which comprises pressing and sintering an abrasive composition in which an elastic powder such as powdered rubber is blended with abrasive grains to form a ground surface of the offset grinding wheel. Only the grinding part to be configured is manufactured in advance, the grinding part is installed in the pressure molding die, and the offset part of the center part of the offset grinding wheel and the base part which is in close contact with the back surface of the grinding part are respectively The gist of the present invention is a method for manufacturing an elastic offset grinding wheel, which comprises arranging an abrasive compound containing an elastic powder such as a powder rubber to be formed, pressing the whole integrally and then firing the whole. .

Another aspect of the present invention is a method of manufacturing an offset grinding wheel, which comprises pressing and sintering an abrasive composition in which an elastic powder such as powdered rubber is blended with abrasive grains, and firing the compound. Only the grinding part that constitutes the part is manufactured in advance, while an abrasive grain composition in which an elastic powder such as powdered rubber is blended with abrasive grains and the like is pressure-formed and fired, and the portion of the offset grinding wheel excluding the grinding part is removed. And a method of manufacturing an elastic offset grinding wheel characterized in that both are separately manufactured and bonded together.

BEST MODE FOR CARRYING OUT THE INVENTION

Next, the contents of the present invention will be described in detail with reference to the drawings. FIG. 1 is a plan view of an example of the elastic offset grinding wheel of the present invention, FIG. 2 is a cross-sectional view along AA, and FIG. 3 is an enlarged cross-sectional view along the arc BB. Reference numeral 1 denotes a grinding portion of the elastic offset grinding wheel 2, which is formed by blending powder rubber with abrasive grains such as silicon carbide similar to those of a known grinding wheel.

3 is a base part 3 of the elastic offset grinding wheel 2
The grinding unit is provided on the back surface of the grinding unit 1 and is formed by mixing more powder rubber than the grinding unit 1 with abrasive grains and the like, and has enhanced flexibility, a thin and relatively high rigidity. Support and reinforce 1. In some cases, the powder rubber compounding amounts of the grinding portion 1 and the base portion 3 may be the same.

The offset portion 4 at the center of the offset grinding wheel is formed by mixing a larger amount of powder rubber than abrasive portion 1 with abrasive grains and the like, and is formed with high flexibility. Offset part 4
Mixes powder rubber equivalent to or more than the base part 3 to the abrasive grains.

A plurality of glass fiber reinforcing cloths 5 are embedded in the elastic offset grinding wheel 2 in the same manner as in a normal offset grinding wheel. In the example of FIG. 2, one glass fiber reinforced cloth 5 is disposed near the boundary between the grinding portion 1 and the base portion 3, inside the base portion 3 and near the back surface of the base portion 3. There are no particular restrictions on the number and positions of the cloths 5 to be arranged, and they can be changed and arranged as needed. As the number of sheets increases, the safety increases, but the rigidity increases and the flexibility decreases. Therefore, the flexibility can be adjusted by the amount of the powdered rubber and the number of the glass fiber reinforcing cloths 5 to be arranged.

The grinding section 1 of the elastic offset grinding wheel of the present invention.
Surface 6 may be flat, but it is desirable to provide irregularities in order to increase the grinding speed. The unevenness is a method in which a grid, radial, or annular groove is provided alone or in combination on the surface. A conventionally known shape such as a method of arranging a large number of projections is used.

The grinding section 1 of the elastic offset grinding wheel of the present invention.
In order to increase the flexibility, it is preferable to make the thickness of the grinding portion 1 and the base portion 3 relatively thin. For example, as shown in the cross-sectional view of FIG. 4, a groove 19 is provided on the surface of the grinding portion 1 to form irregularities, and the total thickness of the grinding portion 1 and the base portion 3 can be made as thin as 2 to 3 mm. .

In the example shown in FIG. 2, a wavefront line 7 extends radially on the surface 6 of the elastic offset grinding wheel 2 and is provided with a corrugated shape 8 having a concentric cross section forming a sawtooth wave. Preferably, the gentle slope of the sawtooth wave faces forward in the rotational direction of the grinding wheel, and the steep slope of the sawtooth wave faces backward in the rotational direction. However, it may be provided so as to face in the opposite direction. The number of radial waves of the wave type 8 is not particularly limited, but a wave number of 10 to 100 is used depending on the diameter of the grinding wheel and the purpose of use. For example, for an elastic offset grinding wheel 2 having a diameter of 100 mm, a wave number of 15 to 50 is preferably used.

In order to manufacture the elastic offset grinding wheel of the present invention, the entirety of the elastic offset grinding wheel 2 is partially provided with an abrasive compound in which the mixing ratio of the abrasive particles and the powder rubber is changed, and the glass fiber reinforced cloth is used. 5 is formed by pressing and molding integrally, and firing is performed. Only the grinding portion 1 is formed into a donut shape and fired, and the base portion 3 and the offset portion 4 are integrally formed and fired. Then, a method of bonding them together, molding and firing only the grinding portion 1, putting this in a mold, and disposing an abrasive compound on the portion to be the base portion 3 and the offset portion 4, After integrally pressing and molding, a method of baking or the like can be used.

The method of integrally molding and firing the entire elastic offset grinding wheel according to the present invention is, for example, in the case of molding the elastic offset grinding wheel 2 shown in FIGS. 1 to 3, as shown in the sectional view of FIG. A mold including an outer mold 9, a lower mold 10 having a radial corrugation on the upper surface, and an upper mold 11 having a lower surface having a shape obtained by inverting the back surface of the elastic offset grinding wheel 2 is used. The center of the lower mold 10 and the upper mold 11 has a center hole 13 through which the pin 12 is inserted.

The lower die 10 is attached to the bottom of the cylindrical outer die 9 of this die.
And a thin layer of the abrasive composition 14a for the grinding unit 1 described later is put into the disc-shaped portion serving as the grinding unit 1 thereon, and the abrasive composition for the offset unit 4 is placed in the center offset unit 4 to be described later. Put the object 14b and level the whole to a certain depth. On the abrasive layer 15, the forming plate whose central part at the lower end is depressed in a letter shape is rotated so that the center of the upper surface of the abrasive layer 15 is filled into a mountain shape, and the glass fiber reinforcing cloth 5 is placed thereon. And then do the same,
Abrasive composition 14c for base portion 3 is placed at a certain depth in a peripheral portion serving as base portion 3 and an abrasive composition for offset portion 4 is provided in a portion serving as offset portion 4 in the center. 1
4b, the glass fiber reinforcing cloth 5 is overlaid on the abrasive grain layer 16, the upper part thereof is pressed by the upper die 11, and pressurized by the hydraulic press device. If necessary, apply the glass fiber reinforcing cloth 5 to the abrasive layer 15
Alternatively, another one or two sheets may be further pressed between the abrasive layers 16 and pressed.

As the abrasive grains used in the production of the elastic offset grinding wheel of the present invention, known abrasive grains for a grinding wheel such as silicon carbide, alumina, zirconia, and fine sand can be used. As the powder rubber, natural rubber or synthetic rubber powder can be used, and instead of powder rubber, elastic synthetic resin powder such as polyurethane resin can be used. As the synthetic rubber powder rubber, SBR, NBR, or any other known synthetic rubber powder can be used. These powdered rubbers are obtained by spray-drying rubber latex, polymerizing by emulsion polymerization, suspension polymerization or solution polymerization, and the like. Powder rubber is used.

The particle size of the powder rubber is not particularly limited, but those having an average particle size of about 50 to 1000 μm are preferably used, and 50 to 300 μm is preferably used. 1000
Those having an average particle diameter larger than μm and those having an average particle diameter smaller than 50 μm can also be used.

The compounding ratio of the abrasive grains to the powder rubber is preferably 10 parts by weight or more, more preferably 30 parts by weight or less, with respect to 100 parts by weight of the abrasive grains in the abrasive composition 14a for the grinding unit 1. . If it is less than 10 parts by weight, the flexibility of the grinding portion 1 is small, and the offset grinding wheel is easily cracked when bent. If the amount is more than 30 parts by weight, the rigidity of the grinding portion 1 is reduced, and the grinding speed is reduced.

The compounding ratio of the abrasive and the powder rubber of the abrasive compound 14c for the base portion 3 is preferably 20 parts by weight or more of the powder rubber to 100 parts by weight of the abrasive, and more preferably 100 parts by weight or more. preferable. The upper limit of the compounding ratio of the powder rubber is 700 parts by weight or less, more preferably 400 parts by weight or less. If the compounding ratio of the powder rubber is small, the elasticity and flexibility of the base portion 3 become small, so that sufficient flexibility cannot be obtained. If the compounding ratio of the powder rubber of the base portion 3 is too large, the base portion 3 becomes too soft and the strength is reduced, and the grinding portion 1 cannot be pressed against the workpiece with sufficient pressure during grinding. , The grinding speed decreases.

Instead of the abrasive grains to be blended in the abrasive grain composition 14c for the base portion 3, hard solid particles other than the abrasive grains, and a reinforcing agent consisting of particles of the same size as the abrasive grains may be blended. Good. The action of the abrasive grains blended in the abrasive grain composition 14c for the base portion 3 is mainly necessary for satisfying the mechanical strength and flexibility of the base portion 3 obtained by press-molding and firing this. This is because it is a function as a strong reinforcing material and does not require a grinding function of abrasive grains. However, at the time of pressure molding of the base portion 3, the abrasive compound 14c for the base portion 3 may be diffused into the grinding portion 1 and mixed therewith.
Preferably, the same abrasive grains are used.

It is preferable that the compounding ratio of the abrasive and the powder rubber in the abrasive composition 14b of the offset portion 4 is 100 parts by weight of the powder rubber or 100 parts by weight or more for 100 parts by weight of the abrasive. The upper limit of the compounding ratio of the powder rubber is 700 parts by weight or less,
More preferred is 400 parts by weight or less. If the compounding ratio of the powder rubber is small, the flexibility of the entire elastic offset grinding wheel 2 is reduced, and the sufficient performance as the elastic offset grinding wheel cannot be exhibited. If the compounding ratio of the powder rubber in the offset portion 4 is too large, the entire elastic offset grinding wheel 2 becomes too soft and cannot exert a sufficient grinding force. For the same reason as in the case of the abrasive grain composition 14c for the base portion 3, hard particles other than abrasive grains are used as reinforcing materials instead of the abrasive grains blended in the abrasive grain composition 14b for the offset portion 4. However, it is preferable to use the same abrasive grains as those used in the grinding unit 1 as the reinforcing material.

Each of the above abrasive compositions 14a, 14b, 14c
Is mixed with a liquid phenol resin such as a resol type or a benzylic ether type as a binder and a powdery phenol resin as a binder in a mixture of the abrasive grains and the powdered rubber to form an abrasive grain compound 14
And The compounding ratio is a mixture of abrasive grains and powder rubber 10
The amount of the binder is suitably from 10 to 30 parts by weight, more preferably from 15 to 25 parts by weight, based on 0 parts by weight. The rigidity increases as the mixing ratio of the binder increases, and the rigidity decreases as the mixing ratio decreases. If the compounding ratio of the binder is less than 10 parts by weight, the strength of that part is reduced. Binder ratio of 3
If the amount is more than 0 parts by weight, the part becomes too hard and the flexibility is reduced.

The abrasive composition 14 may further contain an organic solvent or other liquid fluidity modifier. Further, additives such as powdered fillers such as cryolite and calcium carbonate, coloring agents, and the like, which are added to the abrasive grains during the production of ordinary grinding wheels, can be appropriately compounded.

The pressure at which the abrasive composition 14 is pressed by the mold is not particularly limited, but is usually 100 to 150 kgf / c.
m ² is used. As the pressing temperature, a normal pressing temperature of 80 to 100 ° C. is used.

The sintering temperature of the disc-shaped abrasive grain compact needs to be about 50 ° C. lower than the sintering temperature of a grinding wheel using only ordinary abrasive grains. It is necessary to adjust the firing temperature depending on the mixing ratio. Generally, when the compounding ratio of the powdered rubber is small, the firing temperature can be relatively high. However, when the compounding ratio of the powdered rubber is large, the firing temperature needs to be lowered in consideration of the heat resistance of the powdered rubber. There is. When firing the entire elastic offset grinding wheel 2 of the present invention, a firing temperature usually used is 140 to 150 ° C.
For about 24 hours. In the first 14 hours, the temperature is gradually raised from room temperature to around 140 ° C.
After keeping at 150 ° C. for about 10 hours, the mixture is gradually cooled.

When only the doughnut-shaped grinding portion 1 is separately formed and fired, the firing temperature can be 160 to 170 ° C. By separately firing only the grinding portion 1 having a small mixing ratio of the powder rubber, the firing temperature can be relatively high, and the bonding strength of the abrasive grains in the grinding portion 1 can be increased. Durability can be increased.

In the method in which the ground portion 1 once formed and fired is pressed and formed integrally with the other portions and fired, the method shown in FIG.
Is placed on the lower die 10 of the molding die shown in FIG. 1, the abrasive compound 14b of the offset portion 4 is thinly placed at the center, and the glass fiber reinforcing cloth 5, The abrasive composition 14c for the base part 3 and the abrasive composition 14b for the offset part 4 are arranged, and the whole is integrally press-molded, and then the whole is integrally fired at a firing temperature of 140 to 150 ° C. .

In the production of the elastic offset grinding wheel of the present invention, since the powdered rubber was compounded into the abrasive compound 16, the abrasive compound 16 containing the rubber was put on the reinforcing cloth 17 and pressed. At this time, it is possible to prevent the fiber from being cut due to excessive stress applied to the glass fiber.

The grinding unit 1 previously formed and fired as described above
Is press-formed integrally with the abrasive composition 14b, 14c constituting the other part of the elastic offset grinding wheel 2, and instead of firing, only the base portion 3 and the offset portion 4 are press-formed integrally. Then, the sintering may be performed, and then the separately formed and sintered grinding unit 1 may be bonded with an adhesive or the like. Also, instead of manufacturing the base portion 3 and the offset portion 4 by molding and baking from the abrasive composition 14b, 14c, the base portion 3 and the offset portion 4 are integrally formed of an elastic synthetic resin such as rubber or polyurethane resin. Alternatively, a separately formed and fired grinding unit 1 may be bonded to the grinding unit.

The grinding section 1 of the elastic offset grinding wheel of the present invention.
As the abrasive used in the above, super abrasives such as diamond abrasive, cubic boron nitride (CBN) abrasive, and tungsten carbide abrasive can be used. The super-abrasive grains can be provided only on a part of the grinding section 1, and the super-abrasive grains having the super-abrasive grains bonded by a known bonding method such as metal bond, vitrified bond, resinoid bond, etc. It may be embedded so that a part thereof is exposed on the surface 6.

The elastic offset grinding wheel of the present invention is not only an offset grinding wheel having a normal shape, but also a so-called cup-shaped grinding wheel having a sectional shape as shown in FIG. Can be used for
In this specification, “elastic offset grinding wheel” is defined and used as a term including “elastic cup-type grinding wheel”. In this elastic cup type grinding wheel 17, the nut for fixing the grinding wheel to the rotating shaft at the time of use does not protrude from the grinding surface 18, so that the entire grinding surface 18 can be ground and adhered in parallel to the surface of the workpiece, By compounding the powder rubber with the abrasive grains, the grinding wheel has elasticity and can be ground with low noise and low vibration.

[0042]

According to the elastic offset grinding wheel of the present invention, the grinding wheel has flexibility and is suitable for prying and polishing a curved surface. By providing irregularities on the surface 6 of the grinding unit 1 of the elastic offset grinding wheel 2, clogging of the surface 6 of the grinding unit 1 can be prevented, and the cutting speed is greatly improved.

According to the elastic offset grinding wheel 2 having flexibility of the present invention, the noise during the grinding operation is greatly reduced, the vibration is also greatly reduced, and the working environment is improved.

Even if a plurality of glass fiber reinforced cloths 5 are buried inside the elastic offset grinding wheel, the elasticity and flexibility can be maintained and the grinding wheel is not cracked.
The flexibility can be maintained, and there is no possibility that the grinding wheel is broken during the grinding operation and the fragments are scattered, so that the safety is extremely high. Since the glass fiber reinforcing cloth 5 is buried in the abrasive compound 14 containing the powdered rubber and pressed and molded, there is no cutting of the glass fiber reinforcing cloth 5 which is likely to occur at the time of pressure forming of a normal grinding wheel. As a result of the reinforcing cloth 5 being buried in a complete state, safety is further enhanced.

According to the elastic offset grinding wheel of the present invention,
An extremely long-life grinding wheel can be obtained as compared with a sanding wheel or the like using conventional sandpaper.

Grinding unit 1 of the elastic offset grinding wheel of the present invention
When preformed and fired separately from other parts, it can be fired at a higher temperature than other parts having a high powder rubber compounding ratio, and the strength of the grinding part 1 can be increased and the durability can be increased. .

[Brief description of the drawings]

FIG. 1 is a plan view of an example of an elastic offset grinding wheel of the present invention.

FIG. 2 is an example of an elastic offset grinding wheel according to the present invention.
It is sectional drawing.

FIG. 3 is an arc B of an example of the elastic offset grinding wheel of the present invention.
It is sectional drawing which follows -B.

FIG. 4 is a sectional view of another example of the elastic offset grinding wheel of the present invention.

FIG. 5 is a cross-sectional view illustrating an example of the method for manufacturing an elastic offset grinding wheel of the present invention.

FIG. 6 is a cross-sectional view of an example of the cup-shaped elastic offset grinding wheel of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Grinding part 2 Elastic offset grinding wheel 3 Base part 4 Offset part 5 Glass fiber reinforcement cloth 6 Surface 7 Wave front line 8 Wave type 9 Cylindrical outer die 10 Lower die 11 Upper die 12 Pin 13 Center hole 14 Abrasive compound 15, 16 Abrasive layer 17 Cup type grinding wheel 18 Grinding surface 19 Groove

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 3C063 AA02 AB05 BB02 BB04 BC04 BD01 BD04 BG10 BG15 BG22 CC04 CC17 EE26 FF23

Claims (12)

[Claims] 1. An offset grinding wheel formed by compression molding and baking an abrasive composition obtained by mixing a binder and the like with abrasive grains, wherein at least the abrasive composition forming at least the surface of the ground portion is ground. In addition to compounding the elastic powder such as powder and rubber powder, the abrasive compound which forms the offset portion in the center of the offset grinding wheel includes a solid powder that serves as an abrasive or a reinforcing agent equivalent to an abrasive. An elastic offset grinding wheel characterized in that an elastic powder such as that described above is blended in a larger blending ratio than the abrasive grain blend forming the grinding portion. 2. A method according to claim 1, wherein the abrasive powder is a solid powder which is a reinforcing agent equivalent to the abrasive grains or the abrasive grains. 2. The elastic offset grinding wheel according to claim 1, wherein the mixing ratio is equal to or higher than the abrasive compound forming the grinding portion. 3. A grinding compound comprising an elastic powder such as powdered rubber and the like mixed in a predetermined compounding ratio in each of the grinding portion, the offset portion and the base portion of the offset grinding wheel, is disposed with a glass fiber reinforced cloth interposed therebetween. The elastic offset grinding wheel according to claim 1 or 2, wherein the whole is integrally press-formed and fired. 4. An abrasive composition obtained by compounding said powder rubber with abrasive grains is subjected to pressure molding and baking to form said prefabricated grinding portion together with said abrasive composition forming said offset portion and said base portion. 3. The elastic offset grinding wheel according to claim 1, wherein the elastic offset grinding wheel is integrally formed by pressing and firing. 5. The method according to claim 1, wherein the surface of the grinding portion is provided with irregularities.
An elastic offset grinding wheel according to 2, 3 or 4. 6. A surface of the grinding portion has a corrugated surface, and the corrugation has a large number of wave front lines extending in a substantially radial direction from a central portion of the grinding wheel toward an outer peripheral portion of the grinding wheel. 6. The elastic offset grinding wheel according to claim 1, wherein the shape of the grinding wheel surface in a cross section along a concentric circle concentric with the center is a wavy shape. 7. The abrasive powder according to claim 1, wherein the mixing ratio of the elastic powder in the abrasive composition forming the grinding portion is 10 to 30 parts by weight of the elastic powder with respect to 100 parts by weight of the abrasive. 3, 4 or 5
The described elastic offset grinding wheel. 7. The abrasive composition for forming the offset portion comprises the abrasive powder and the elastic powder, and 100 parts by weight of the abrasive and the like.
The composition according to claim 1, which is blended at a blending ratio of 100 to 700 parts by weight.
An elastic offset grinding wheel according to 2, 3, 4 or 5. 8. An elastic offset grinding wheel according to claim 1, wherein said offset grinding wheel is a cup-shaped offset grinding wheel. 9. An abrasive grain composition for forming said grinding portion, wherein super abrasive grains such as diamond abrasive grains, cubic boron nitride (CBN) abrasive grains, and tungsten carbide abrasive grains are blended.
The elastic offset grinding wheel according to 3, 4, 5, 6, 7 or 8. 10. An abrasive made of abrasive powder in which a binder is mixed between an upper die and a lower die in a cylinder set so that a disk-shaped lower die is fitted to the bottom and the axis is vertical. In a method for manufacturing a grinding wheel in which the compound is sandwiched and pressed at a high pressure to form a disc, and then the disc-shaped molded product is heated and fired, a grinding portion of a peripheral portion of the upper surface of the lower mold in the cylinder is formed. An abrasive composition is prepared by mixing an elastic powder such as powdered rubber with abrasive grains to a certain thickness in a portion to be molded to form an abrasive layer, and an offset portion in the center of the upper surface of the lower mold is formed. An abrasive in which an elastic powder such as powdered rubber is blended with a solid powder which is a reinforcing material equivalent to abrasive grains or abrasive grains to a certain thickness in a portion at a greater blending ratio than the abrasive grain composition in the portion forming the grinding portion. A grain composition is disposed, a glass fiber reinforcing cloth is disposed thereon, and the back surface of the grinding section is further placed on the abrasive composition forming the grinding section. An abrasive compound containing an elastic powder such as powdered rubber that forms a base portion to be formed is disposed, and the elastic powder is further added to a portion forming an offset portion in the center of the mold. A method for manufacturing an elastic offset grinding wheel, comprising: disposing an abrasive compound compounded in a larger amount than an object, and pressure-molding the whole. 11. A method for manufacturing an offset grinding wheel, comprising:
Press-molding and baking an abrasive compound in which elastic powder such as powdered rubber is mixed with abrasive particles, pre-fabricating only the grinding part that constitutes the grinding surface of the offset grinding wheel, The grinding part is installed, and an abrasive compound containing an elastic powder such as a powdered rubber that forms a base part which is in close contact with an offset part in the center of the offset grinding wheel and a back surface of the grinding part is disposed on the grinding part. And a method of manufacturing the elastic offset grinding wheel, wherein the whole is integrally press-formed and then fired. 12. A method for manufacturing an offset grinding wheel, comprising:
Abrasive grains in which an elastic powder such as powdered rubber is blended with abrasive grains are pressure-formed and fired, and only the grinding portion that constitutes the grinding surface of the offset grinding wheel is manufactured in advance. The abrasive grain composition containing the elastic powder is pressure-formed and fired, and a portion of the offset grinding wheel excluding the ground portion is separately manufactured, and the two are bonded together. Production method.