JP2003011064A - Manufacturing method for grindstone, grindstone, and grinding method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a manufacturing method for a grindstone capable of providing a strong pressing pressure of abrasive grains and being suitable for grinding a three-dimensional shape. SOLUTION: This manufacturing method for the grindstone comprises a process for applying parting agent 3 for preventing the adhesion of the grindstone 17 to a surface of a workpiece 1, a process for charging a grindstone raw material 6 containing at least abrasive grains and bond into a space 5 having the similar shape as the workpiece 1, a process for stirring the grindstone raw material 6 in the space 5, and a process for solidifying or gelatinizing the liquidlike grindstone raw material 6. Since parting agent is supplied to the surface of the workpiece, a capillary phenomenon on the surface of the workpiece is reduced, and the grindstone can be easily released from the workpiece. Moreover, since the abrasive grain raw material is stirred in the space, the abrasive grains are three-dimensionally and uniformly dispersed when the liquidlike grindstone raw material is solidified or gelatinized.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shape transfer grindstone to which a shape of a workpiece is transferred, a method for manufacturing the shape transfer grindstone, and a polishing method using the shape transfer grindstone.

[0002]

2. Description of the Related Art With the rapid progress of technological innovation, high precision of industrial products is required. Along with this demand, the shape of a workpiece such as an industrial product or a part which is symmetrical with respect to polishing or grinding becomes complicated, and it is often demanded that a fine and highly accurate dimension and a high finished surface roughness are required.

However, the final finishing of a work requiring such a fine surface finish or high-precision dimensions often still depends on manual work. If the manual process can be mechanized or labor-saving, the processing cost and the work process time can be shortened. Further, in such a manual polishing work, even a skilled worker has a limit in the precision of mirror polishing on the processed surface.

Under such circumstances, ELID grinding using a solid grindstone has been carried out as a method for realizing highly accurate mirror polishing of a workpiece. This is a method in which an electric field is applied to a solid grindstone to perform polishing and grinding while performing dressing. There are few scratches on the polishing surface,
High finishing accuracy is possible, but it is applied to objects with limited shapes such as planes and cylinders.

Further, there is a polishing method using a soft lapping grindstone other than the solid grindstone. This is polyvinyl
This is a method in which a polymer wrap material such as acetal or sodium alginate is melted on the surface of the chamois and lapping is performed, but the polishing efficiency is poor because the polishing pressure (grinding stone pressing pressure) cannot be large.

Further, as a method of polishing a free shape, there is a method of using a konjac grindstone, a gelatin grindstone, or a wax grindstone in which a substance that changes phase from liquid to solid is used as a binder. These have the advantage that any shape of grindstone can be made freely by forming a shape with a liquid and solidifying it, but because of the capillary phenomenon between the work piece, the abrasive grains, and the binder, the grindstone There is almost no protrusion of abrasive grains on the surface of. Therefore, the polishing efficiency is poor.

On the other hand, the inventors of the present application have proposed a polishing method using a magnetic fluid or an MR fluid containing abrasive grains, in which the arrangement and dispersion of the abrasive grains can be controlled by a magnetic field. This content is a magnetic fluid (including abrasive grains) immersed in the surface of the workpiece, and when a magnetic field of a predetermined strength is applied to the magnetic fluid, the magnetic fluid and the workpiece undergo relative motion such as vibration or oscillation. This is a method of polishing by performing. As an example of a polishing method using such a magnetic fluid, Japanese Patent Application Laid-Open No. 1-1 is known.
No. 35466, JP-A-4-336954, JP-A-4-41173, and Japanese Patent No. 3081911.

[0008]

However, these conventional methods for polishing a work piece by immersing a fluid containing abrasive grains in the work surface and applying relative motion to the work piece in this way are as follows. Since the abrasive material is a highly fluid liquid, the pressing pressure of the abrasive particles against the processed surface is weak and the polishing efficiency is low. Therefore, although it can be applied to the final step in the grinding and polishing steps of the workpiece, it is not suitable for the grinding step or the polishing intermediate step.

Further, in the prior art, even if a magnetic fluid is used and polishing is performed in a state in which the abrasive grains are array-controlled by applying a magnetic field of a predetermined strength, the fluidity of the magnetic fluid does not provide sufficient polishing efficiency. Absent. Further, when this magnetic fluid polishing method is applied to a three-dimensional shape, there is a problem that the corners and sharp edges, which are the features of the three-dimensional shape, are rounded, causing sagging.

Therefore, it is an object of the present invention to provide a method for manufacturing a grindstone, a grindstone and a polishing method, which are suitable for polishing a three-dimensional shape in which the pressing pressure of the abrasive grains is high.

[0011]

In order to solve the above problems, the present inventor has taken advantage of the free shape property (the shape is three-dimensionally free according to the shape of a work piece) which is an advantage of a fluid grindstone containing abrasive grains. Can be deformed into a small shape, and by pouring it into a narrow gap, the fluid grinding stone can be configured inside a narrow and closed shape that human hands and tools cannot enter), which is an advantage of polishing with a solid grinding stone. It has become possible to increase the polishing pressure (grinding stone pressing pressure).

Then, the present inventor applies a mold release agent for alleviating the capillary phenomenon on the surface to the workpiece to disperse the abrasive grains in a liquid similar in shape to the workpiece while securing the protrusion amount of the abrasive grains. A grindstone with a good shape transfer was created and this grindstone was solidified.

That is, the invention of claim 1 applies a step of applying a release material for preventing the grindstone from sticking to the surface of the workpiece, and a grindstone containing at least abrasive grains and a binder in a space similar to the workpiece. According to the method for manufacturing a grindstone, which comprises a step of charging a raw material, a step of stirring the grindstone raw material in the space, and a step of solidifying or gelling the liquid grindstone raw material, as described above. Solved the problem.

According to the present invention, since the mold release agent is applied to the surface of the workpiece, the capillary phenomenon on the surface of the workpiece is alleviated,
The grindstone can be easily released from the work piece. Further, since the abrasive grain raw material is stirred in the space, the abrasive grains are three-dimensionally and uniformly dispersed when the liquid grindstone raw material is solidified or gelled (that is, the segregation of the abrasive grains is reduced). As a result, a solid grindstone having abrasive grains protruding on any of the surfaces and having good dispersibility of the abrasive grains can be obtained, so that the pressing pressure of the abrasive grains can be made large and any three-dimensional free-form surface can be polished. be able to.

Further, since there is unevenness due to a slight gap between the grindstone and the workpiece and the dispersibility of the abrasive grains, it is possible to secure polishing with a minute stroke while removing polishing dust. By using such a gap, the wear of the grindstone due to polishing is promoted to increase the gap between the grindstone and the workpiece, and by using the increased gap to secure the polishing stroke of the next surface, the corner portion is not sagged It is also possible to polish a three-dimensional shape.

Since the specific gravity of the abrasive grains is heavier than the specific gravity of the binder, if the magnet raw material is not stirred, the liquid grindstone raw material is solidified while the abrasive grains are precipitated. In this case, there is a protrusion of the abrasive grains on the bottom surface of the whetstone in which the abrasive grains are precipitated, and the workpiece can be polished, but the protrusion of the abrasive grains cannot be obtained on the side surface of the whetstone, which causes a problem that polishing cannot be performed. .

Further, the invention of claim 2 is characterized in that the release agent contains abrasive grains.

Since the grindstone has a cohesive force with the machined surface and the machined surface has irregularities (finished surface roughness), it is difficult for the grindstone to separate from the workpiece, and the shape of the grindstone collapses during separation. There is a risk. As a means for solving this problem, a release agent containing abrasive grains is applied to the processed surface so that the abrasive grains are filled as free abrasive grains in the gaps of the processed surface irregularities (finished surface roughness). The rolling movement of the abrasive grains is used to perform the mold release, and the cohesive force on the machined surface is mitigated by the layer of the mold release agent, which facilitates the mold release.

The invention of claim 3 is characterized in that the release agent contains a component capable of dissolving the binder.

Since the grindstone side of the abrasive grains in the gap between the irregularities (finished surface roughness) of the processed surface is fastened to the grindstone, the rolling of the abrasive grains is regulated at the time of detachment. The release agent slightly dissolves the wheel surface to remove this fastening force.

According to a fourth aspect of the present invention, the space is slightly smaller than the shape of the workpiece when the shape of the workpiece is concave, and slightly larger than the shape of the workpiece when the shape of the workpiece is convex. Is characterized by.

In the case of a three-dimensional workpiece, if there is no space in the three directions of the vertical part, the horizontal part and the height part, the grindstone will be generated due to the unevenness of the processed surface (finish surface roughness) and the adhesive force. Cannot be taken out of the work piece. Therefore, a space having a similar shape to that of the workpiece is formed by the thickness of the release agent layer.

The invention of claim 5 is characterized in that the grindstone raw material contains a magnetic field sensitive substance.

The magnetic field-sensitive material for the purpose of reducing the abrasive grain precipitation by dispersing poor in the liquid _{(MnZn · Fe 2 O 3,} BaO · 6Fe 2 O
₃ , NiZn ・ Fe ₂ O ₃ , Coγ ・ Fe ₂ O ₃ , γ ・ Fe ₂ O ₃ , γ ・ Fe ₂ O ₃ , permalloy, electromagnetic soft iron, etc.) as the raw material for the grinding stone, and the viscosity is given by applying a magnetic field to the raw material in the liquid or sol state. Due to the effect and the stirring effect, it is possible to ensure uniform dispersion of the abrasive grains.

According to a sixth aspect of the present invention, in the step of stirring the grindstone raw material in the space, any one of a magnetic field, a mechanical vibration, and an electric field is applied to the grindstone raw material, or a combination of these is applied to the grindstone. Characterized by feeding to raw materials.

The raw material of the grindstone is abrasive grains (affected by the electric field),
When it is composed of a substance containing three or more kinds of a magnetic field sensitive substance (affected by a magnetic field) and a binder, stirring can be performed by applying a magnetic field or an electric field to a grindstone raw material (liquid or sol state). Further, since the three types of substances have different specific gravities, mechanical vibration promotes stirring. these,
In order to disperse the abrasive grains, any one of the above stirring methods may be applied, or two or more stirring methods may be used in combination.

The invention of claim 7 is characterized in that, when a magnetic field is applied to the grindstone material, a plurality of magnetic field generating sources are used to apply the magnetic field to the grindstone material from a plurality of mutually different directions.

In the present invention, the stirring effect by the magnetic field is given to the grindstone raw material in the liquid or sol state. For the purpose of further improving the stirring, two or more magnetic field sources, preferably three or more magnetic field sources are arranged vertically, horizontally, vertically and horizontally, diagonally, etc.,
By changing the direction of the magnetic field and stirring, the abrasive grains are dispersed more uniformly.

According to an eighth aspect of the present invention, a coil is provided in the magnetic field generation source, an alternating current is made to flow through the coil, or an electric current made to flow in the coil is ON-OFF controlled, or is made to flow in the coil. It is characterized in that the current is changed.

According to the present invention, the stirring effect can be increased by changing the direction of the magnetic field applied to the grindstone raw material or by applying the magnetic field strength to the grindstone raw material.

The invention of claim 9 is characterized in that the stirring by the magnetic field is performed before the grindstone raw material is solidified.

As is well known, after the grinding stone raw material is solidified, the abrasive grains hardly move even when a strong magnetic field is applied. Applying more energy than is necessary may cause minute cracks in the solid grindstone. Therefore, by applying a magnetic field to an appropriate solidification progress state, it is possible to create a solid solid grindstone having good energy efficiency and no cracks.

According to a tenth aspect of the present invention, the grindstone raw material is powder or liquid at the time of being charged into the space, and the grindstone raw material is powder at the time of being charged into the space. Is characterized in that the grindstone raw material is brought into a liquid state in the space, and then the grindstone raw material is stirred in the space.

The present invention considers the safety and handleability when handling a binder having a high melting point. Handling a binder with a high melting point may cause accidents such as burns.
It was decided to insert the grindstone raw material into the space at a low temperature. That is, with a binder having a low melting point, the grindstone raw material is inserted in a liquid state, and with a binder having a high melting point, the grindstone raw material is inserted as powder and melted in the space.

According to the invention of claim 11, a step of charging a grindstone raw material containing at least abrasive grains, a binder and a magnetic field sensitive substance into a space having a shape similar to that of the workpiece, and using a plurality of magnetic field generation sources,
By applying a magnetic field to the grindstone raw material from a plurality of directions different from each other, a step of stirring the grindstone raw material in the space, and a step of solidifying or gelling the liquid grindstone raw material The above-mentioned problems have been solved by the manufacturing method.

According to the present invention, a plurality of magnetic field generation sources are arranged vertically, horizontally, vertically and horizontally, obliquely, etc., and the direction of the magnetic field is changed to stir, whereby more uniform dispersion of the abrasive grains is performed. Since the abrasive particles are three-dimensionally and substantially evenly dispersed when the liquid grindstone raw material is solidified or gelled, there is protrusion of the abrasive particles on any surface of the solid grindstone, and any surface of the three-dimensional free shape can be formed. A grindstone suitable for polishing is obtained. On the other hand, when a magnetic field is applied to the grindstone raw material from only one direction, the abrasive grains can be two-dimensionally and substantially evenly dispersed, but three-dimensionally and substantially uniformly (for example, dispersed like a mesh). , Or dispersed like a building window).

According to a twelfth aspect of the present invention, there is provided a grindstone in which a liquid grindstone raw material containing at least abrasive grains and a binder is solidified or gelled in accordance with the shape of a workpiece. The above-mentioned problems have been solved by a grindstone characterized by being distributed substantially evenly in dimensions. here,
The expression “three-dimensionally substantially evenly distributed” means that the abrasive grains are arranged at substantially equal intervals in any of the X, Y, and Z directions and at substantially equal pitches.

According to the present invention, a grindstone suitable for polishing an arbitrary surface having a three-dimensional free shape can be obtained for the above reason.

According to a thirteenth aspect of the present invention, a step of charging a grindstone raw material containing at least abrasive grains and a binder and a grindstone holding portion for holding the grindstone into a space similar to the workpiece, and the liquid grindstone raw material The above-mentioned problem is solved by a method for manufacturing a grindstone, which comprises a step of solidifying or gelling.

In order to move the grindstone relative to the workpiece, it is necessary to attach a grindstone holding portion to the grindstone. According to the present invention, the whetstone can be firmly held by the whetstone holding portion.

According to a fourteenth aspect of the present invention, the method for manufacturing a grindstone further comprises a step of stirring the grindstone raw material in the space by applying a magnetic field to the grindstone raw material using a magnetic field source. It is characterized in that the grindstone holding portion becomes a part of the magnetic field circuit.

The present invention shows a structure capable of applying a strong magnetic field to the inner surface of the workpiece. Since the grindstone holding part is part of the magnetic field circuit, the magnetic resistance of the magnetic field circuit is reduced, and it is possible to strengthen the magnetic field even with a weak magnetic field source, and magnetic field stirring according to the shape of the workpiece is possible. is there.

A fifteenth aspect of the invention is characterized in that a coil is provided in the grindstone holding portion or in the vicinity thereof.

By disposing a coil, which is a magnetic field generating source, in the vicinity of the fluid grindstone, it becomes easy to control the stirring of the abrasive grains. As is well known, the magnetic field lines are most susceptible to the effect of being closest to the magnetic field source. Therefore, a coil, which is a magnetic field generation source, was formed in the grindstone holding portion or in the vicinity of the grindstone holding portion. Further, the same effect can be obtained by using a permanent magnet as the magnetic field generation source other than the coil.

The invention of claim 16 is characterized in that the grindstone holding portion has a plurality of columns.

Supporting the whetstone with a large number of columns has the effect of increasing the whetstone holding force in the up / down, left / right, front / rear, and diagonal directions. Therefore, the present invention includes a column provided with a step and a column which is bent. In addition, by arranging a large number of columns, magnetic field agitation adapted to the shape of the workpiece becomes possible.

According to a seventeenth aspect of the present invention, a groove or a step is formed in the whetstone holding portion, or another component is attached to the whetstone holding portion so that the fastening area between the whetstone holding portion and the whetstone can be increased. It is characterized by

Since the strength of the solidified grindstone is not sufficient,
When taking out the grindstone from the work piece, the grindstone is likely to be deformed or cracked. Further, when trying to obtain a large polishing pressure, a large force is applied to the main wheel joint portion. In order to increase these strengths, the grindstone strength is increased by equivalently increasing the grindstone fastening area by attaching grooves, steps, or other parts to the grindstone coupling portion.

The invention of claim 18 is characterized in that a soft magnetic material is used in the magnetic field circuit of the grindstone holding portion.

As is well known, the lower the magnetic resistance of the magnetic field circuit, the stronger the magnetic field. Therefore, general iron-based magnetic field circuit,
If a cobalt-based ferromagnetic material is used, a strong magnetic field will be obtained, but since residual magnetism remains, magnetic field stirring cannot be performed well. As a countermeasure against this, a soft magnetic material such as permalloy, electromagnetic soft iron, or silicon steel, which has a low magnetic resistance and a small residual magnetism, is used in the magnetic circuit.

According to a nineteenth aspect of the present invention, there is provided a grindstone in which a grindstone raw material containing at least abrasive grains and a binder is solidified or gelled in accordance with the shape of a workpiece, and the liquid grindstone raw material is solidified or gelled. The above problem is solved by the grindstone characterized in that the grindstone holding portion for holding the grindstone is fastened to the grindstone.

According to the present invention, it is necessary to attach the grindstone holding portion to the grindstone in order to move the grindstone relative to the workpiece. According to the present invention, the whetstone can be firmly held by the whetstone holding portion.

The invention of claim 20 is characterized in that the workpiece is polished by moving the grindstone relative to the workpiece, and the grindstone holding portion is used for the relative movement.

Since the strength of the solidified grindstone is not sufficient,
Grinding with a whetstone without a whetstone holding part causes whetstone chipping and deformation, and the polishing pressure cannot be increased. Therefore, the polishing time becomes long and uneven polishing is likely to occur. In order to increase the polishing pressure, it is necessary to have a strong whetstone holding portion with a large fastening area with the whetstone. In this way, the fastening area of the grindstone is secured by the grindstone coupling part, and the relative polishing motion and the polishing pressure are applied to one end of this grindstone holding part, so that the polishing pressure can be increased, and the uneven polishing and the polishing time can be shortened. Becomes

According to a twenty-first aspect of the present invention, a grindstone obtained by solidifying or liquefying a liquid grindstone raw material containing at least abrasive grains and a binder in accordance with the shape of the work is pressed against the processed surface of the work, In a polishing method that gives relative movement to the grindstone, the first surface of the work piece is polished and the whetstone is depleted by moving the grindstone in the first direction in which the grindstone can move relative to the work piece. Using a gap between the first step and the grindstone of the workpiece caused by the wear of the grindstone, by performing relative movement of the grindstone in a second direction different from the first direction, the workpiece The above-mentioned problem is solved by a polishing method characterized by including a secondary step of polishing the second surface of the. Here, the first and second directions may be rotational directions or linear directions.

The present invention positively promotes wheel wear and relates this wheel wear to the stroke of the polishing action to the next surface. That is, a gap due to wear of the grindstone is secured, and a stroke of relative motion and a direction of relative motion corresponding to this gap are given to the grindstone to polish the workpiece. Specifically, in the relative movement when polishing a workpiece using a solid grindstone, the relative movement is performed from the direction in which the movable distance of the grindstone is the largest in the workpiece, so that the grindstone wears down. This increases the gap between the grindstone depleted portion and the first surface of the workpiece. By forming this gap, the stroke amount of the relative movement of the second surface of the workpiece is secured, and the grindstone is moved relative to the polishing. Therefore, a plurality of three-dimensional free-form surfaces can be polished.

According to a twenty-first aspect of the present invention, in the polishing method, a gap between the second surface of the workpiece and the grindstone caused by wear of the grindstone is further utilized to make a third direction different from the second direction. And a third step of polishing the third surface of the workpiece by relatively moving the grindstone.

The clearance between the worn surface of the grindstone and the second surface of the workpiece increases due to the grindstone wear due to the relative movement. As the grindstone wears successively, the grindstone becomes smaller gradually. This allows
The stroke of relative movement of the grindstone is secured, and the movable direction is increased. Therefore, a workpiece having a three-dimensional free shape can be polished.

A twenty-third aspect of the present invention is characterized by including a step of applying a grindstone dissolving solution for dissolving a binder to the surface of the grindstone.

When the grindstone solution is applied to the surface of the grindstone, the wear due to the relative movement between the grindstone and the workpiece is accelerated. Further, this wear reduction effect is promoted by bringing the temperature of the grindstone surface close to the melting point.

The invention of claim 24 is characterized in that the step of applying the grindstone dissolving liquid is repeated.

When the grindstone is depleted by relative movement, grindstone scraps and grindstone solution are gradually discharged from the inner surface of the workpiece. Therefore, it is possible to give a constant amount of wear to the grindstone by successively applying the grindstone dissolving liquid.

According to a twenty-fifth aspect of the present invention, the polishing method further comprises a step of applying a release agent to the surface of the workpiece so as to prevent the grindstone from adhering to the surface of the workpiece. The feature is that the grindstone solution is also used.

The present invention is a method for preventing the possibility of operator error due to the addition of chemicals such as a grindstone solution and a release agent. By using both the release agent and the grindstone solution, the number of types is small and operator error can be minimized.

The invention of claim 26 is characterized by comprising a step of blowing air to the polishing object in order to remove grinding wheel debris and polishing chips from the polishing surface.

The present invention is a method for preventing uneven polishing due to grindstone abrasion debris, polishing debris, etc. on the surface of a workpiece. A stable polishing surface can be obtained by applying an appropriate air flow to the workpiece and discharging the scraps from the inside of the processing surface.

A twenty-seventh aspect of the present invention is characterized in that the grindstone is controlled so as to polish the next surface after completing a preset number of polishing operations.

When a grindstone in which a liquid containing abrasive grains is solidified is pressed against the work surface of a workpiece and relative movement is applied between the work and the grindstone, the abrasion loss of the grindstone and the number of polishing operations (for example, reciprocating motion) and The correlation of Using this correlation,
It is possible to finish the preset number of polishing operations and set the polishing conditions such as the relative movement direction for polishing the next surface, the relative movement stroke, and the polishing pressure. This allows automatic polishing without human involvement.

[0069]

BEST MODE FOR CARRYING OUT THE INVENTION In the present invention, a powder or liquid containing abrasive grains is filled in a work piece coated with a release agent, stirred in a liquid state and solidified to solidify a grindstone similar to the work piece. To produce. Therefore, the present invention is a polishing method corresponding to small-quantity production or single-item production. In addition, the present invention has a wide range of application over the entire workpiece, such as a place that is out of reach of humans and a workpiece having a narrow space.

A particular field of application of the present invention is in the general area of abrasive grain processing. Examples of main fields of use include spectacle lenses, prisms of specific shapes, mirrors, and the like as optical fields. In addition, dies for various industrial products, casing parts, jewelry, watch parts, etc., gauges, cylinders, bearings, bearings, etc. that require higher dimensional accuracy.
It can also be applied to grinding and polishing of cams, gears, etc. Further, in the field of semiconductors, it can be applied to the finishing of silicon wafers, which are the basis of integrated circuits, and as a special example, medical products such as dentures and artificial bones.

Hereinafter, a method for manufacturing a grindstone for forming a shape transfer grindstone (shape conforming grindstone) using a grindstone raw material containing the abrasive grains of the present invention, and a polishing method for polishing using the grindstone will be described.

Since the applicable range of the polishing method according to the present invention covers a wide range as described above, the content of the abrasive grains to be used and the content of the grinding stone raw material containing the abrasive grains to be used depend on the material, shape and finish of the workpiece. Will be decided.

As the material of the abrasive grains used, in the case of the magnetically sensitive abrasive grains, specifically, iron oxide (Fe ₂ O ₃ , Fe ₃ O ₄ ), coating abrasive grains (SiC plated, diamond plated) ),
As non-magnetic abrasive grains alumina (Al ₂ O ₃ ), silica (SiO ₃ ),
Examples thereof include silicon carbide (SiC) and diamond (C). Regarding the particle size of the abrasive grains, the higher the required finishing accuracy, the smaller the particle size used.

As the binder, water, various oils,
Wax, soap, oleic acid, etc. can be mentioned. The binder may be one kind or several kinds. Further, a surfactant may be added to prevent the abrasive grains and the magnetically sensitive substance from coagulating.

As a method of changing the phase from a liquid to a solid, there can be mentioned a method of utilizing a temperature phase change of gel or solid at a melting point temperature or lower and sol or liquid at a melting point temperature or higher. In the case of fats and oils, a method of utilizing a chemical reaction in addition to the temperature phase change can be considered. Further, in the case of a polymer binder, a method utilizing a photopolymerization reaction can be considered.

A method of controlling the dispersion of abrasive grains in a liquid before gelation or solidification is extremely important in the present invention. This is because the grindstone surface in contact with the processed surface of the workpiece has a great influence on the polishing rate, polishing accuracy, and polishing efficiency depending on the state of the abrasive grains. Since the raw material of the grindstone contains a binder having different specific gravity, a magnetically sensitive substance, and abrasive grains, precipitation and segregation of the abrasive grains occur in a liquid state, and the number of effective abrasive grains on the polishing surface varies. When the workpiece has a three-dimensional shape, it is necessary to uniformly control the number of effective abrasive grains within the three-dimensional shape.

When the fluid containing magnetism and the workpiece are placed in a magnetic field environment, the magnetically responsive substance is arranged along the magnetic field lines.
Further, since the number of magnetic lines of force per unit area is proportional to the magnetic field strength, the density of the magnetically sensitive substance can be controlled by controlling the magnetic field strength. By changing the direction in which the magnetic field strength is applied to up, down, left, right, front and back, the magnetic field sensitive substance stirs in the liquid, so that the abrasive grains are also stirred accordingly. In this way, the distribution of abrasive grains in the liquid can be controlled as required.

The dispersion of the abrasive grains in the liquid is controlled at the time of solidification under the magnetic field environment in the case of the fluid containing magnetism and under the electric field environment in the case of using the charged abrasive grains.

When the charged abrasive grains are used, the abrasive grains are charged to one of positive and negative charges, which is different from the case of a magnetic fluid or an MR fluid that always has both polarities (N pole and S pole). A repulsive force is generated between the charged abrasive grains. Since the charged abrasive grains themselves exert a force to evenly distribute them in the liquid, it is not always necessary to perform the solidification or gelation in an electric field environment. But,
By controlling the distribution of the charged abrasive grains in the liquid by applying an electric field, the distribution state becomes more uniform.

A grindstone containing gelled or solidified abrasive grains is ground or polished by causing relative motion such as vibration or vibration with respect to the surface of a workpiece to be processed. Depending on the state of solidification, there may be a case where the main grindstone and the processed surface are in close contact with each other. In such a state, polishing efficiency is poor even if relative movement is attempted between them. Therefore, in such a case, relative movement is performed with the whetstone dissolving liquid applied to the contact surface between the whetstone and the processed surface to slightly melt the whetstone surface. In addition, as a method of melting the contact surface between the main grindstone and the processed surface, a temperature control method for raising the surface of the grindstone above the freezing point, or applying a chemical having a lower freezing point than the grindstone to the work surface of the workpiece There is a method such as keeping.

As a method of causing relative motion between the main grindstone and the workpiece, in addition to generating vibration by using mechanical force, a method of polishing by using force by magnetism or force by electric field, and further by force by magnetism A method in which mechanical force is used in combination, a method in which electric field and mechanical force are used in combination, and a method in which magnetic force and electric field are used in combination may be employed.

The direction of relative movement is one-dimensional or two-dimensional if it is a plane and three-dimensional if it is a three-dimensional surface, depending on the shape of the machined surface of the workpiece. As a relative motion for coping with these three dimensions, a three-dimensional surface can be polished by applying a one-dimensional or two-dimensional operation to each of the three-dimensional constituent surfaces and successively performing partial polishing.

The stroke of the relative movement is adjusted according to the intended processing. If you want to perform large grinding in a unit time, use a grindstone containing large abrasive grains to generate a relative movement of a large stroke with the workpiece, and in the case of mirror finishing where precise dimensional accuracy is required. , A grindstone containing small abrasive grains is used to generate a small stroke of relative motion with the work piece. Since the settings of these abrasive grains and strokes vary depending on the finishing purpose of the workpiece, adjustment is made for each workpiece. Attach the grindstone holding part to the polishing device to polish the condition, finish the workpiece,
It is also possible to perform grinding and polishing by automatic control by inputting data of the shape of the workpiece.

Next, as a concrete example of the present invention, a method for manufacturing a new grindstone will be described with reference to FIG.

In FIG. 1 (1), a mold release agent 3 for preventing the grindstone from adhering to the work surface 2 of the work 1 is applied. The release agent contains components that dissolve the abrasive grains and the binder. The application may be brush painting or spraying. By applying the release agent 3, a similar space 5 smaller than the space surrounded by the surface to be processed is formed by the thickness of the release agent layer 4. In this example, the shape of the work piece is concave, and the similar space 5 is slightly smaller than the shape of the work piece. On the other hand, when the shape of the workpiece is convex, the similar space 5 is slightly larger than the shape of the workpiece.

In FIG. 1 (2), a powdery grinding stone raw material 6 and a grinding stone holding portion 7 are inserted into the similar space 5. The grinding stone raw material contains abrasive grains, a binder and a magnetic field sensitive substance. Then, the temperature of the grindstone raw material is raised in the similar space 5 to liquefy it (the figure shows a case where the temperature of the powdery grindstone raw material 6 is raised by the heater 8). At this time, the temperature of the workpiece 1 may be normal temperature as long as it is close to the melting point of the raw material of the grindstone. When using a grindstone raw material having a high melting point, it is preferable to preheat the workpiece 1 in advance. In this embodiment, the powdery grindstone raw material is charged in the similar space 5, but of course the liquid grindstone raw material may be poured.

The grindstone holding portion 7 has a plurality of columns.
In order to make the fastening area between the whetstone holding part and the whetstone large,
A groove or a step is formed in the grindstone holding portion, or another component is attached to the grindstone holding portion.

In FIG. 1 (3), a grindstone raw material 9 in a liquid state
A magnetic field is applied to and stirring is performed. In the figure, three magnetic field generation sources 10, 11, 12 are provided, and coils 13, 14, 15 are wound around each magnetic field generation source. Then, an electric current is applied to the coils 13, 14 and 15 to apply a magnetic field to the grindstone raw material 9 from a plurality of mutually different directions (in this embodiment, the upper and left three directions). These coils 13, 14, 15
The directions of the magnetic fields generated by And
The magnetic lines of force generated from the coils 13, 14, 15 spread radially.

A magnetic field generation source 10 is coupled to the grindstone holding portion 7, and the grindstone holding portion 7 also becomes a part of the magnetic field circuit. A soft magnetic material is used for the grindstone holding portion 7. In addition, the current flowing through each coil is changed, or an alternating current is applied to the coils, so that the abrasive grain agitation suitable for the shape is performed.
Alternatively, the current passed through the coil may be ON-OFF controlled. In the figure, Δ indicates an abrasive grain.

In this embodiment, the whetstone raw material is agitated by applying a magnetic field to the whetstone raw material, but in addition to this, either one of mechanical vibration and electric field is given to the whetstone raw material, or these are used in combination. The whetstone raw material may be agitated by feeding it to the whetstone raw material.

In FIG. 1 (4), the grindstone is cooled in the similar space 5 to be solidified, and the grindstone is pulled out in the removal direction. At this time, since the grindstone raw material enters the groove 16 of the grindstone holding portion, the solidified grindstone 17 can be easily pulled out. With such a structure that allows a large contact cross-sectional area between the grindstone holding portion 7 and the solidified grindstone 17, a large polishing pressure can be applied to the relative movement of polishing.

FIG. 1 (5) is an enlarged view of the polishing section 18 of FIG. 1 (4), showing a contact state between the grindstone, the release agent layer 4 and the surface to be processed. By moving the abrasive grains in the release agent 4 as shown in the figure,
The difficulty of removal due to the unevenness of the surface roughness is mitigated, and the difficulty of removal due to the surface adhesive force is mitigated because of the solvent of the release agent 3.

Next, a new polishing method will be described as an embodiment of the present invention with reference to FIG.

In FIG. 2 (1), the solidified grindstone 17 (shape transfer grindstone) created in FIG. 1 (4) is placed in the similar space 5 and the grindstone holding portion 7 or grindstone 5 is moved in the left-right direction (the method of processing surface). (Line direction)
A polishing pressure is applied to, and relative movement (← →) is applied in the vertical direction (tangential direction of the processing surface) as the first direction in which the grindstone can move relative to the workpiece. At this time, the grindstone dissolving liquid 19 is appropriately applied to polish the first surface while depleting the grindstone.
The grindstone solution 19 is also used as a release agent. Whetstone 5
The number of reciprocating movements of the grinding wheel 5 is set in advance so that when the polishing operation of this number is completed, the next surface is polished.
The reciprocating motion of is controlled.

In FIG. 2 (2), by polishing in FIG. 2 (1), the grindstone surface which was in contact with the machined surface as shown in this figure is depleted and the gap between the machined surface and the grindstone increases. Utilizing this gap, as shown in the figure, a polishing pressure is applied to the grindstone holding portion or the grindstone in an oblique direction (the normal direction of the machining surface), and a second direction different from the first direction, which is almost orthogonal to this, is applied. Relative motion (← →) is given in the diagonal direction (tangential direction of the machined surface) as the direction of. The stroke of relative movement is set smaller than the gap. Also at this time, the second surface is polished while the grindstone dissolving liquid 19 is appropriately applied to reduce the wear of the grindstone.

In FIG. 2 (3), by grinding in FIG. 2 (2), the grindstone surface which was in contact with the surface to be machined as shown in this figure is depleted and the gap between the machined surface and the grindstone is increased. Using this gap, polishing pressure is applied to the grindstone holding part or grindstone in the vertical direction (radial direction of the surface to be processed) as shown in this figure, and the left-right direction as a third direction different from the second direction. Relative motion (← →) is given to (tangential direction of the work surface). The stroke of relative movement is set smaller than the gap. At this time as well, the grindstone dissolving liquid 19 is appropriately applied to polish the third surface while depleting the grindstone.

In FIG. 2 (4), the grindstone finally becomes small, and the transfer shape deteriorates as shown in this figure. According to the polishing method of the present invention, polishing is possible regardless of the combination of inclinations of the processed surface of the workpiece. Further, in the case of improving the dimensional accuracy or polishing to a mirror surface, it is possible to improve the dimensional accuracy and the finished surface roughness by repeating the steps of FIGS. 1 and 2.

Further, in order to remove grindstone wear debris and polishing debris from the work surface, air may be blown to the work surface by a blower or the like not shown.

In the above-mentioned embodiment, an example in which a grindstone is manufactured in the workpiece to be polished and the workpiece is polished by the grindstone has been described. The present invention is not limited to this embodiment, and various modifications can be made. For example, a grindstone may be manufactured in a model having a shape similar to that of the work, the grindstone may be removed from the model, the grindstone removed from the model may be inserted into the work, and the work may be polished.

[Brief description of drawings]

FIG. 1 is a process drawing showing a method for manufacturing a shape transfer grindstone in one embodiment of the present invention.

FIG. 2 is a process diagram showing a polishing method according to an embodiment of the present invention.

[Explanation of symbols]

1 ... Processed product 2 ... Surface to be processed 3 ... Release agent 4 ... Release agent layer 5 ... similar space 6 ... Raw material for whetstone 7 ... Whetstone holding part 8 ... Heater 9 ... Liquid whetstone raw material 10 ... Magnetic field source 11 ... Magnetic field source 12 ... Magnetic field generator 13 ... Coil 14 ... Coil 15 ... Coil 16 ... Groove holding section 17 ... Solidifying whetstone 18 ... Polishing part 19 ... Grinding stone solution

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Tokuji Umehara             Tokyo Hachioji City Bessho 2-chome 46-3-102 (72) Inventor Hagiwara             1241-5 Haguro-cho, Kofu City, Yamanashi Prefecture (72) Inventor Isao Shibata             1198-87 Fuse, Tatomi Town, Nakakoma District, Yamanashi Prefecture F term (reference) 3C047 FF09 HH11                 3C049 AA02 AA09 AA12 AC05 CB03                 3C063 AA02 AB05 BB01 BC01 CC30                       EE19

Claims (27)

[Claims] 1. A step of applying a release material for preventing a grindstone from sticking to the surface of a workpiece, and a step of charging a grindstone raw material containing at least abrasive grains and a binder into a space similar to the workpiece. A method of manufacturing a grindstone, comprising: a step of stirring the grindstone material in the space; and a step of solidifying or gelling the liquid grindstone material. 2. The method of manufacturing a grindstone according to claim 1, wherein the release agent contains abrasive grains. 3. The method for manufacturing a grindstone according to claim 1, wherein the release agent contains a component that dissolves the binder. 4. The space is slightly smaller than the shape of the workpiece when the shape of the workpiece is concave, and slightly larger than the shape of the workpiece when the shape of the workpiece is convex. Item 4. A method for manufacturing a grindstone according to any one of Items 1 to 3. 5. The method for manufacturing a grindstone according to claim 1, wherein the grindstone raw material contains a magnetic field sensitive substance. 6. In the step of stirring the grindstone raw material in the space, any one of a magnetic field, mechanical vibration, and an electric field is applied to the grindstone raw material, or a combination thereof is applied to the grindstone raw material. The method for manufacturing a grindstone according to any one of claims 1 to 5, which is characterized by the above. 7. The method of manufacturing a grindstone according to claim 6, wherein when a magnetic field is applied to the grindstone raw material, a plurality of magnetic field generation sources are used to apply the magnetic field to the grindstone raw material from a plurality of mutually different directions. . 8. A coil is provided in the magnetic field generation source,
8. The method of manufacturing a grindstone according to claim 7, wherein an alternating current is applied to the coil, or an electric current applied to the coil is ON-OFF controlled, or an electric current applied to the coil is changed. 9. The stirring by the magnetic field is performed before the grindstone raw material is solidified.
The method for producing a grindstone according to. 10. The grindstone raw material is powder or liquid at the time of charging into the space, and if the grindstone raw material is powder at the time of charging into the space, inside the space The method for producing a grindstone according to any one of claims 1 to 9, wherein the grindstone raw material is brought into a liquid state in step 1, and then the grindstone raw material is stirred in the space. 11. A step of charging a grindstone raw material containing at least abrasive grains, a binder and a magnetic field-sensitive substance into a space having a shape similar to that of a workpiece, and a plurality of magnetic field generation sources are used, and the grindstone raw material is supplied from a plurality of different directions. By applying a magnetic field to the grindstone material,
A method of manufacturing a grindstone, comprising: a step of stirring the grindstone raw material in the space; and a step of solidifying or gelating the liquid grindstone raw material. 12. A grindstone in which a liquid grindstone raw material containing at least abrasive grains and a binder is solidified or gelled according to the shape of a workpiece, wherein the abrasive grains are three-dimensionally substantially uniform in the grindstone. A grindstone characterized by being distributed in. 13. A step of charging a grindstone raw material containing at least abrasive grains and a binder, and a grindstone holding portion for holding the grindstone into a space similar to the workpiece, and solidifying or gelling the liquid grindstone raw material. A method of manufacturing a grindstone, comprising: 14. The method for manufacturing a grindstone further includes a step of stirring the grindstone raw material in the space by applying a magnetic field to the grindstone raw material using a magnetic field generation source, wherein the grindstone holding portion has a magnetic field. 14. The method of manufacturing a grindstone according to claim 13, wherein the grindstone is a part of a circuit. 15. The method for manufacturing a grindstone according to claim 14, wherein a coil is provided at or near the grindstone holding portion. 16. The method of manufacturing a grindstone according to claim 13, wherein the grindstone holding portion has a plurality of columns. 17. A groove or a step is formed in the grindstone holding portion, or another component is attached to the grindstone holding portion so that a fastening area between the grindstone holding portion and the grindstone can be increased. Item 17. A method for manufacturing a grindstone according to any one of items 13 to 16. 18. The method of manufacturing a grindstone according to claim 14, wherein a soft magnetic material is used in the magnetic field circuit of the grindstone holding portion. 19. A grindstone in which a liquid grindstone raw material containing at least abrasive grains and a binder is solidified or gelled in accordance with the shape of a workpiece, which is obtained by solidifying or gelling the liquid grindstone raw material. A grindstone in which a grindstone holding portion that holds the grindstone is fastened to the grindstone. 20. The grindstone according to claim 19, wherein the grindstone is polished by moving the grindstone relative to the work, and the grindstone holding portion is used for the relative movement. 21. A grindstone in which a liquid grindstone raw material containing at least abrasive grains and a binder is solidified or liquefied in accordance with the shape of the workpiece is pressed against the machined surface of the workpiece, and between the workpiece and the grindstone. In a polishing method that provides relative movement, a primary step of polishing the first surface of the workpiece by depressing the stone relative to the workpiece in a first direction in which the stone can move relative to the workpiece, and abrading the stone, Utilizing the gap between the first surface of the workpiece and the grindstone caused by the wear of the grindstone, by relatively moving the grindstone in a second direction different from the first direction, the second surface of the workpiece And a second step of polishing. 22. The polishing method further utilizes a gap between the second surface of the workpiece and the grindstone caused by wear of the grindstone, and relatively moves the grindstone in a third direction different from the second direction. The polishing method according to claim 21, further comprising a tertiary step of polishing the third surface of the workpiece. 23. The polishing method according to claim 21, further comprising a step of applying a whetstone dissolving liquid that dissolves a binder to the surface of the whetstone. 24. The polishing method according to claim 23, wherein the step of applying the grindstone dissolving liquid is repeated. 25. The polishing method further comprises a step of applying a release agent for preventing the grindstone from adhering to the surface of the workpiece, wherein the release agent and the grindstone solution are used together. The polishing method according to claim 23 or 24. 26. The polishing method according to claim 21, further comprising a step of blowing air to the working surface in order to remove grindstone debris and polishing waste from the working surface. 27. The grinding wheel is controlled so as to polish the next surface after completing a predetermined number of reciprocating motions.
6. The polishing method according to any one of 6 above.