JP2010105103A - Polishing grinding wheel being fibrous and porous - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a polishing grinding wheel capable of radiating heat of the grinding tool and a workpiece generated during working, and preventing the occurrence of clogging to enable continuous working and being applicable to very great number of uses. <P>SOLUTION: In this polishing grinding wheel being fibrous and porous, a basic material including a binding material containing a thermosetting resin or a thermoplastic resin and abrasive grains has a first cavity having volume ratio of 0.1-3.0 and is molded into fibers having diameter of 0.5-10 mm to form the fibrous basic material, which is molded while keeping a fibrous state to form a second cavity in this basic material. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention relates to a polishing wheel, and more particularly to a polishing wheel useful for difficult-to-cut materials such as titanium.

Conventional elastic and inelastic grinding stones have a good balance of polishing properties, scratch resistance, safety, wear resistance, water resistance, cost, etc., and their applications are often limited (Patent Documents) 1).
Japanese Patent Laid-Open No. 05-154752

  In the case of a conventional elastic / inelastic grindstone, particularly an elastic rubber grindstone, when a large grindstone having a high specific gravity is used, it is necessary to take measures such as limiting the number of rotations for safety reasons.

  In order to solve the above problems, the safety aspect can be eliminated by using a hard and hard grindstone such as an inelastic grindstone. However, when such a grindstone is used, there is a problem that the polished surface of the workpiece is rough and scratches are observed, the shape is broken, and the surface of the grindstone is clogged.

  One possible cause of the shape collapse is that the workpiece changes due to frictional heat. In addition, the frictional heat is also stored in the grindstone itself, and in some cases, the grindstone may be damaged.

  In general, when clogging occurs, dressing is performed each time and a new grindstone surface is regenerated and used, resulting in an increase in the consumption of the grindstone. Further, when the consumption amount of the grindstone increases, the replacement frequency increases, resulting in an increase in cost.

  In many cases, stable polishing is difficult due to the above problems, and when automated, the polishing machine apparatus tends to be complicated.

  As a result of intensive studies to achieve the above-mentioned problems, the present inventors have found that the above-mentioned problems can be overcome by the following grinding stone, and have completed the present invention. That is, according to the present invention, the following polishing grindstone is provided.

[1] A base material including a binder containing a thermosetting resin or a thermoplastic resin and abrasive grains has a first void of 0.1 to 3.0 in volume ratio, and has a diameter of 0. A polishing grindstone having a second gap formed by forming into a fibrous base material of 5 to 10 mm, and forming the fibrous base material while maintaining the fiber state.

[2] The polishing grindstone according to [1], wherein the first gap is formed of an inorganic balloon or an organic balloon.

[3] The polishing grindstone according to the above [1] or [2], wherein the final void ratio of the first void and the second void is 0.1 to 5.0 in volume ratio.

[4] The polishing grindstone according to any one of [1] to [3], wherein the mass ratio of the abrasive grains to the binder is 0.01 to 3.0.

[5] The polishing stone according to any one of [1] to [5], wherein the specific gravity is 0.3 to 1.5 g / cm ³ and the rubber hardness is JIS A20 to JIS D99.

[6] The polishing grindstone according to any one of [1] to [6], wherein the thermosetting resin is an epoxy resin.

  The polishing grindstone of the present invention is capable of self-dissipating heat due to the unique structure of multiple voids. Thereby, both the heat storage to a grindstone and the heat_generation | fever of a to-be-processed object can be reduced simultaneously. Furthermore, weight reduction, safety, and low cost can be realized by providing many voids.

  The grindstone of the present invention is a grindstone having a number of layers of voids made by entanglement of the substrate and the fibrous substrate, and the voids dissipate heat in the grindstone generated during polishing. Furthermore, it is effective for reducing the frictional heat generated during processing on the workpiece.

  The whetstone of the present invention is particularly porous so that clogging is minimal, and the sharpness and stability can be adjusted relatively easily depending on the composition, so it can be used in a very high range of applications. Applicable.

  What should be noted in the present invention is that the polishing ability is extremely high and the sustainability is also high. Further, since a small amount of abrasive material is used, it can be said to be an elastic grindstone that is lightweight and extremely low in cost.

  BEST MODE FOR CARRYING OUT THE INVENTION The best mode for carrying out the present invention will be described below, but the present invention is not limited to the following embodiment, and is based on the ordinary knowledge of those skilled in the art without departing from the gist of the present invention. It should be understood that modifications and improvements as appropriate to the following embodiments also fall within the scope of the present invention.

  In the grinding wheel of the present invention, the base material containing the binder and the abrasive grains containing the thermosetting resin or thermoplastic resin has a first void of 0.1 to 3.0 by volume ratio, And it is shape | molded by the fiber shape of diameter 0.5-10mm, and it is set as a fibrous base material, and it has a 2nd space | gap by shape | molding the said fibrous base material, hold | maintaining a fiber state. That is, the grindstone of the present invention gives a void by forming the base material into a fiber shape having a diameter of 0.5 to 10.0 mm and then forming it into a predetermined shape so as to be entangled while maintaining the fiber state. It is characterized by that.

  In the polishing grindstone of the present invention, the diameter of the fibrous base material is 0.5 to 10 mm. If the diameter of the fibrous base material is less than 0.5 mm, one fiber state cannot be maintained and the shape tends to be lost. If the diameter exceeds 10 mm, the second void after molding In the case of a polishing operation, particularly during manual processing, the interval tends to be difficult to process.

  In this invention, a base material has the 1st space | gap of 0.1-3.0 by volume ratio. The void is formed by an inorganic or organic balloon, or formed by foaming a binder. When the volume ratio of the first void to the substrate is less than 0.1, clogging tends to occur, and when it exceeds 3.0, the brittleness increases and the life of the grindstone tends to decrease. .

  In the present specification, the volume ratio of the first gap refers to a volume ratio calculated by calculation. Specifically, first, the volume is calculated from the mass and specific gravity of each component to be blended in the base unit mass. A volume obtained by adding the calculated volume of each component is defined as a basic volume in the base unit mass.

  On the other hand, a molded product having no second void is prepared, and the reciprocal of the specific gravity obtained from the mass of the molded product and the volume calculated from the outer shape is applied to the unit mass. The obtained volume is the calculated volume of the molded product having no second void in unit mass. The difference between the calculated volume and the basic volume is the void volume. The ratio between the void volume and the basic volume is referred to as the volume ratio of the first void.

  In the polishing grindstone of the present invention, the fibrous base material is molded while maintaining the fiber state to form the second gap. Holding the fiber state means that the fiber state can be visually recognized.In the present invention, the state in which the fiber state can be visually recognized is maintained even in a part, and even between some adjacent fibers. A void (second void) may be formed.

  In the polishing grindstone of the present invention, the final void ratio of the first void and the second void is 0.1 to 5.0 in volume ratio. When the final porosity is less than 0.1, clogging tends to occur and the polishing rate tends to decrease, and when it exceeds 5.0, the coating tends to become brittle.

  In this specification, the final porosity means a volume ratio calculated by calculation. Specifically, first, the volume is calculated from the mass and specific gravity of each component to be blended in the base unit mass. A volume obtained by adding the calculated volume of each component is defined as a basic volume in the base unit mass.

  On the other hand, the unit mass is multiplied by the reciprocal of the specific gravity obtained from the mass of the molded product and the volume calculated from the outer shape. The obtained volume is the calculated volume of the molded product in unit mass. The difference between the calculated volume and the basic volume is the void volume. The ratio between the void volume and the basic volume is called the final void ratio.

  In the polishing wheel of the present invention, the mass ratio of the abrasive grains to the binder is 0.01 to 3.0. When the mass ratio of the abrasive grains to the binder is less than 0.01, the grinding force tends to decrease, and when it exceeds 3.0, the probability of occurrence of scratches tends to increase.

The polishing wheel of the present invention has a specific gravity of 0.3 to 1.5 g / cm ³ . When the specific gravity is less than 0.3 g / cm ³ , the grinding force tends to decrease, and when it exceeds 1.5 g / cm ³ , the dynamic balance tends to be lost.

The polishing grindstone of the present invention has a rubber hardness of JIS A20 to JIS D99. When the rubber hardness is less than JIS A20, the grinding force tends to decrease, and when the rubber hardness exceeds JIS D99, the familiarity with the value mineral tends to deteriorate.
[Binder]

  The binding material of the grinding wheel of the present invention is a thermosetting resin or a thermoplastic resin. Among these, a thermosetting resin is preferable. Specifically, synthetic rubber, phenol resin, epoxy resin, melamine resin, urethane resin and the like can be exemplified. Synthetic rubber, urethane resin and epoxy resin are preferable, and epoxy resin is particularly preferable.

  The epoxy resin used in the present invention has at least two epoxy groups in one molecule, and is preferably solid or liquid at room temperature. For example, bisphenol A type, bisphenol F type, bisphenol S type, phenol novolac type, cresol novolac type, biphenyl type, naphthalene type, aromatic amine type and the like are exemplified, but not limited thereto. In addition, these can be used individually or in combination.

[Abrasive grain]
As abrasive grains used in the present invention, for example, diamond abrasive grains, CBN abrasive grains, alumina-based abrasive grains, alumina-based abrasive grains by sol-gel sintering, silicon carbide-based abrasive grains, zirconia abrasive grains, alumina-zirconia abrasive grains, Examples thereof include silica, chromium oxide, cerium oxide, and the like. These can be used alone or in admixture of two or more. The type and combination of abrasive grains to be used are appropriately selected according to conditions such as grinding and the material of the material to be polished.

  Abrasive grain size can be used from submicron abrasive grains of less than 1 μm to an average grain size of 1 mm or more. These are appropriately selected according to conditions such as grinding and the material of the material to be polished.

  In this invention, it is preferable that the mass ratio of the abrasive grain with respect to a binder is 0.01-3. If it is less than 0.01, the grinding force tends to decrease and the original ability of the grindstone tends to be lost, and if it exceeds 3, the probability of occurrence of scratches tends to increase.

[Inorganic or organic balloon]
Examples of the inorganic balloon used in the present invention include a glass balloon, a silica balloon, an alumina balloon, and a shirasu balloon. Moreover, as an organic balloon used by this invention, a phenol balloon etc. can be illustrated, for example, The Matsumoto microsphere F series, an expand cell DE series, and an expand cell WE series are mentioned by the following brand names. it can.

  The inorganic or organic balloon used in the present invention preferably has a particle size of 0.01 to 2 mm. When the particle size of the inorganic or organic balloon is less than 0.01 mm, clogging tends to occur, and when it exceeds 2 mm, the proportion of the resin portion decreases, and the overall holding power tends to decrease and become brittle. is there. The inorganic or organic balloon used in the present invention is not particularly limited in shape and the like as long as the particle size is in the above range, and any material such as resin or rubber can be used. It may be selected appropriately.

  In addition, in order to form the 1st space | gap without using an inorganic or organic balloon, the method of foaming a base material can also be employ | adopted. In this case, a conventionally known foam material may be appropriately blended with the base material.

  EXAMPLES Hereinafter, although this invention is demonstrated concretely based on an Example, this invention is not limited to these Examples.

[Method for Manufacturing Grinding Wheel of the Present Invention]
Example 1
[Manufacture of grinding wheels]
With reference to FIG. 1, a method for producing a polishing wheel of the present invention will be described.

(A) Mixing:
As shown in FIG. 1A, using a mixer (model number: HBI90) 1 manufactured by Kanto Blender Kogyo Co., Ltd., the mixture shown in Table 1 is mixed and dispersed uniformly, and then a curing agent is added and stirred. The substrate 3 was obtained (required time: about 10 minutes).

(B) Pre-molding:
As shown in FIG. 1B, the uniformly dispersed mixed base material 3 is extruded into a fibrous shape using a Bonny mixer (model number: No. 5) 5 to form a fibrous base material 7 (fiber diameter of about 2 mm). The rubber mold 9 was packed (time required: about 10 minutes).

(C) Press molding:
After completion of packing, as shown in FIG. 1C, the mold 9 was placed in the hydraulic press 11 and molded (required time: about 120 minutes).

(D) Removal:
Thereafter, the wheel-shaped fibrous porous polishing grindstone 13 was taken out from the mold 9. The shape of the obtained wheel-shaped fibrous porous polishing grindstone 13 was as shown in FIG.

[Workpiece]
As a workpiece for the polishing test, a rectangular parallelepiped block of pure titanium material 50 × 20 × 10 was used.

[Polishing method]
The wheel-shaped fibrous porous grinding wheel 13 obtained above was mounted on a double-headed grinder (model number: GT15) 31 manufactured by Hitachi as shown in FIG. The results are shown in Table 2.

(Comparative Example 1)
A polishing grindstone having the composition shown in Table 3 was produced according to a conventional method. The obtained grindstone has no first and second voids. Using this grindstone, a polishing test was conducted under the same conditions as in Example 1. The results are shown in Table 2.

  In the case of the grindstone of Example 1, there was no tendency to clog at all. When the grindstone of Example 1 and the grindstone of Comparative Example 1 were used at the same polishing time (60 seconds), the whetstone of Example 1 was three times as large. The difference in surface roughness has come out. Further, the heat generated by the workpiece and the grindstone due to frictional heat during processing was also generated 1.5 times as much as that of the grindstone of Comparative Example 1 compared to the grindstone of Example 1. From this fact, it can be seen that heat is easily stored in the workpiece and the grindstone in the case of a structure having no gap inside the grindstone, such as the comparative example 1 grindstone. In addition, there is a possibility that the workpiece is burned by this frictional heat and the commercial value is lost, and by providing a lot of voids as in the grindstone of Example 1 and self-dissipating heat, the heat accumulation on the workpiece and the grindstone is increased. It is reduced. In addition, it can be molded very lightly with a specific gravity of 1/4 or less.

(Comparative Example 2)
A grinding wheel having the composition shown in Table 4 was produced according to Example 1. However, the formulation of Comparative Example 2 does not use an organic balloon, and there is no first void. Using this polishing wheel, a polishing test was conducted under the same conditions as in Example 1. The results are shown in Table 2.

(Comparative Example 3)
A grinding wheel having the composition shown in Table 5 was produced according to Example 1. However, in Comparative Example 3, the step of extruding into a fiber shape was omitted and the rubber mold 9 was packed as it was, so there was no second gap. Using this polishing wheel, a polishing test was conducted under the same conditions as in Example 1. The results are shown in Table 2.

  When the grindstone of Comparative Example 2 was used, as shown in Table 2, the heat storage in the grindstone and the heat generation to the workpiece showed numerical values equivalent to those of the grindstone of Example 1, but the surface roughness was that of Example 1. A numerical value lower than that of the whetstone came out. When the grindstone of Comparative Example 3 was used, the surface roughness was higher than that of the product of the present invention as shown in Table 2, but regarding the heat generation on the workpiece, the grindstone of Comparative Example 1 was not as good. There was no high frictional heat. Therefore, it can be seen that by providing a large number of gaps, it is possible to effectively suppress heat storage and heat generation in the grindstone and on both surfaces of the workpiece that occur during processing.

(reference)
The volume ratio and the final porosity of the first void of the grindstone of Example 1 were calculated as follows. Table 6 shows the mass, specific gravity, and volume of each component in 100 g of the substrate.

(Volume ratio of the first void)
From Table 6, the basic volume of the substrate is as follows.
31.2 (cm ³ ) +18.8 (cm ³ ) +15.625 (cm ³ ) = 65.525 (cm ³ ) (1)

The volume of the substrate 100 g is calculated using the specific gravity of Comparative Example 3 in Table 2 as follows.
100 (g) ÷ 0.78 (g / cm ³ ) = 128.21 (cm ³ ) (2)

The volume of the first void is obtained by (2)-(1).
128.21 (cm ³ ) −65.525 (cm ³ ) = 62.585 (cm ³ ) (3)

From the above, the volume ratio of the first gap ((3) / (1)) is as follows.
62.585 (cm ³ ) ÷ 65.525 (cm ³ ) = 0.955

(Final porosity)
From Table 2, since the specific gravity of Example 1 is 0.54 g / cm ³ , the volume of the base material 100 g is as follows.
100 (g) ÷ 0.54 (g / cm ³ ) = 185.19 (cm ³ ) (4)

The total volume of the first gap and the second gap is obtained by (4)-(1).
185.19 (cm ³ ) −65.525 (cm ³ ) = 119.57 (cm ³ ) (5)

From the above, the final porosity ((5) / (1)) is as follows.
119.57 (cm ³ ) ÷ 65.525 (cm ³ ) = 1.825

  The polishing wheel of the present invention can be used for various polishing processes.

It is a schematic diagram which shows the manufacturing method of the wheel type fibrous porous polishing grindstone which concerns on one Embodiment of this invention. 1 is a perspective view and a partially enlarged view of a wheel-type fibrous porous polishing grindstone according to an embodiment of the present invention. It is a typical perspective view which shows the use condition of the wheel type fibrous porous polishing grindstone which concerns on one Embodiment of this invention.

Explanation of symbols

1: Mixer, 3: Base material, 5: Mixer, 7: Fibrous base material, 9: Mold, 11: Press, 13: Wheel-type fibrous porous polishing grindstone, 23: First gap, 25: Second , 27: abrasive grains, 29: binder, 31: grinder.

Claims (6)

A base material comprising a binder containing a thermosetting resin or a thermoplastic resin and abrasive grains,
A first void having a volume ratio of 0.1 to 3.0 is formed into a fibrous substrate having a diameter of 0.5 to 10 mm, and the fibrous substrate is a fiber. A polishing grindstone having a second gap by being molded while maintaining the state.   The grinding wheel according to claim 1, wherein the first gap is formed of an inorganic balloon or an organic balloon.   The polishing grindstone according to claim 1 or 2, wherein the final void ratio of the first void and the second void is 0.1 to 5.0 in volume ratio.   The polishing grindstone according to any one of claims 1 to 3, wherein a mass ratio of the abrasive grains to the binder is 0.01 to 3.0. The specific gravity is 0.3 to 1.5 g / cm ³ and the rubber hardness is JIS A20 to JIS D99. The polishing grindstone according to any one of claims 1 to 5.   The grinding wheel according to any one of claims 1 to 6, wherein the thermosetting resin is an epoxy resin.

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