JP3076274U - Offset whetstone - Google Patents

Abstract

(57) [Problem] To provide an offset whetstone in which vibration generated in a whetstone can be suppressed even when a hard material is ground, the precision of a machined surface is improved, and a grinding operation is easy. An offset grindstone 10 includes a grindstone 11 whose abrasive grains are diamond and a back plate 12 to which the grindstone 11 is attached, wherein the material of the backplate 12 is glass fiber. Since the material of the back plate 12 is glass fiber, the back plate 12 absorbs the force that the abrasive grains receive from the hard material when grinding a hard material such as a stone. For this reason, the offset whetstone 10
Since the occurrence of vibration can be suppressed, the machining surface accuracy is improved. In addition, since the energy in the low frequency region where the human body is sensitive can be reduced, the bodily sensation vibration of the operator is reduced, fatigue is reduced, and the grinding operation is facilitated.

Description

[Detailed description of the invention]

[0001]

[Technical field to which the invention belongs]

 The present invention relates to an offset grinding wheel. More specifically, the present invention relates to an offset whetstone used for grinding hard materials such as stones, tiles, and concrete products.

[0002]

[Prior art]

 FIGS. 5A and 5B are a single view of the conventional offset grindstone 110, in which FIG. 5A is a plan view, and FIG. 5B is a sectional view taken along the line BB of FIG. 5A. As shown in FIG. 1, a conventional offset grindstone 110 includes a grindstone 111 whose abrasive grains are diamond, and a back plate 112 to which the grindstone is attached. The back plate 112 is made of a metal such as aluminum or plastic, and a grinding stone 111 is bonded to the back plate 112 with an adhesive such as an epoxy resin to manufacture the offset grinding stone 110.

[0003]

[Problems to be solved by the invention]

 However, when a conventional offset whetstone 110 is attached to a hand-held tool to grind a hard material such as a stone, the hardness and the elastic modulus of the hard material and diamond, which are abrasive grains, are both high. The impact when the hard material comes into contact is large, and the force that the grinding stone 111 receives from the hard material increases. At this time, the back plate 112 is made of aluminum, plastic, or the like, has high rigidity, and cannot absorb the force applied to the grindstone 111 from the hard substance, so that the offset grindstone 110 generates vibration. For this reason, there is a problem that large irregularities are formed on the processing surface, and the processing accuracy is reduced. Further, since the vibration generated in the grindstone 111 is transmitted to the hands and arms of the worker, there is a problem that the fatigue becomes severe and the grinding work is difficult.

[0004] In view of such circumstances, the present invention provides an offset whetstone that can suppress the vibration generated in the whetstone even when grinding a hard material, improves the machining surface accuracy, and facilitates the grinding operation. Aim.

[0005]

[Means for Solving the Problems]

 The offset whetstone of claim 1 is an offset whetstone comprising a whetstone whose abrasive grains are diamond and a back plate to which the whetstone is attached, wherein the material of the back plate is glass fiber. I do. The offset whetstone according to claim 2, wherein the abrasive whetstone is an abrasive whetstone composed of abrasive cloth paper whose abrasive particles are diamond and a back plate to which the abrasive cloth paper is attached, wherein the material of the back plate is glass fiber. Features.

According to the invention of claim 1, since the material of the back plate is glass fiber, when the hard material such as stone is ground, the back plate absorbs the force received by the abrasive grains from the hard material. . For this reason, it is possible to suppress the occurrence of vibration on the offset grinding stone, thereby improving the machining surface accuracy. Moreover, since the energy in the low frequency region where the human body is sensitive can be reduced, the bodily sensation vibration of the operator is reduced, the fatigue is reduced, and the grinding work is facilitated. According to the invention of claim 2, since the material of the back plate is glass fiber, when grinding a hard material such as a stone material, the back plate absorbs a reaction force received by the abrasive cloth paper from the hard material. For this reason, the occurrence of vibrations in the offset grindstone can be suppressed, and the machining surface accuracy is improved. In addition, since the energy in the low frequency region where the human body is sensitive can be reduced, the bodily sensation vibration of the operator is reduced, the fatigue is reduced, and the grinding work is facilitated.

[0007]

[Embodiment of the invention]

 Next, an embodiment of the present invention will be described with reference to the drawings. First, the offset grindstone 10 of the first embodiment will be described. FIG. 1 is a single view of the offset grindstone 10 of the first embodiment, in which (A) is a plan view and (B) is a cross-sectional view taken along the line BB of (A). As shown in FIG. 1, the offset grindstone 10 according to the first embodiment includes a diamond grindstone 11 whose abrasive grains are diamond, and a back plate 12 to which the diamond grindstone 11 is attached. It is characterized in that the material is glass fiber.

The diamond grindstone 11 includes a grindstone portion 13 and a base 14. The grindstone portion 13 is a grindstone in which the abrasive grains are diamond and the binder is, for example, a phenol resin or the like, and is formed in a donut-shaped disc shape. A base 14 is attached to the back surface of the grindstone portion 13 with an adhesive such as an epoxy resin. The base 14 is formed in the shape of a donut disk, and its material is, for example, silicon carbide. The base 14 may not be provided, and the grindstone portion 13 may be directly attached to the back plate 12.

Now, the back plate 12 important in the present invention will be described. The back plate 12 is formed by laminating a plurality of sheets formed by weaving glass fiber yarns in a mesh shape, and hardening the sheets with an adhesive such as an epoxy resin. The back plate 12 is formed in a dish shape with a concave center by press molding. At the center of the back plate 12, a metal mounting member 15 for mounting the offset grindstone 10 to a tool (not shown) is provided.

The offset grindstone 10 of the first embodiment is manufactured by attaching a front surface of a back plate 12 and a back surface of a base 14 of the diamond grindstone 11 with an adhesive such as an epoxy resin. Have been.

Next, the operation and effect of the offset grinding wheel 10 of the first embodiment will be described. First, the mounting portion 15 of the offset grindstone 10 of the first embodiment is mounted on the rotating shaft of the tool. Then, the rotation axis of the tool is rotated, the offset grindstone 10 is rotated, and the surface of the diamond grindstone 11 of the offset grindstone 10 is brought into contact with a hard material such as a stone, a tile, or a concrete product, and grinding is started.

When the diamond wheel 11 of the offset wheel 10 comes into contact with a hard material, the diamond wheel 11 receives a force from the hard material, and the force is transmitted from the diamond wheel 11 to the back plate 12. Since the material of the back plate is glass fiber, the back plate 12 absorbs the force applied to the diamond grindstone 11 from the hard substance due to the deformation of the back plate 12. For this reason, according to the offset grindstone 10 of the first embodiment, it is possible to suppress the occurrence of vibration in the offset grindstone 10 itself, so that the machining surface accuracy is improved.

In addition, even if vibration occurs in the offset grindstone 10, the energy in a low frequency region where the human body is sensitive becomes small. Therefore, according to the offset grindstone 10 of the first embodiment, since the bodily sensation vibration of the operator is reduced, the fatigue of the operator is reduced, and the grinding operation is facilitated.

Next, an offset grindstone 20 according to a second embodiment will be described. The offset grindstone 20 of the second embodiment comprises a polishing cloth 21 having abrasive particles of diamond and a back plate 22 to which the polishing cloth 21 is attached. It is characterized by fibers. The offset grindstone 20 is characterized in that the abrasive cloth 21 is attached to the back plate 12 with an adhesive 23 such as an epoxy resin, instead of the diamond grindstone 11.

The abrasive cloth 21 is made of a material made of, for example, cotton, polyester, or the like, and is attached with diamond particles scattered over the entire surface. The diamond particles do not need to be scattered over the entire surface of the cloth, and may be attached only to a part of the cloth. Therefore, the offset grindstone of the second embodiment can suppress the occurrence of vibration on the offset grindstone 20, similarly to the offset grindstone of the first embodiment, thereby improving the machining surface accuracy. In addition, since the energy in the low frequency region where the human body is sensitive can be reduced, the bodily sensation vibration of the operator is reduced, fatigue is reduced, and the grinding operation is facilitated.

Next, examples of the offset grindstone of the present embodiment will be described. Example 1 Example 1 is an offset grindstone 20 according to the second embodiment, in which a plurality of sheets formed by weaving polishing cloth paper 21 in which abrasive particles are diamond and knitting glass fiber threads in a mesh shape are stacked. This is an offset whetstone attached to the back plate 22 that has been hardened.

Comparative Example 1 is an offset whetstone in which abrasive cloth paper whose abrasive particles are diamond is attached to a back plate of an aluminum plate.

The comparative method is based on the case where the offset whetstone of Example 1 and the offset whetstone of Comparative Example 1 are respectively attached to a hand-held power tool (Hitachi Koki PDA-100D) and the granite is polished with each power tool. And the spectrum of the vibration acceleration in the normal direction of the work material of the power tool were compared. The grinding resistance was measured using a strain gauge (manufactured by KISTLER: Model 9257A). The vibration acceleration on the power tool was measured using an acceleration sensor (Dytran instruments inc., Model 3115A).

FIG. 3 is a table comparing the grinding resistance when granite is ground according to Example 1 and Comparative Example 1. In the figure, the grinding force Fn is a back force acting in the normal direction of the work material. Further, the variation ratio Fn-AC · RMS is a root-mean-square value of the vibration region of the grinding resistance of 400 Hz or less, and indicates the variation ratio of the grinding resistance Fn. As shown in the figure, the grinding resistance Fn at the time of grinding has a larger value in Example 1 than in Comparative Example 1. However, the value of the variation ratio Fn-AC · RMS of the grinding resistance Fn is about 10% of the grinding resistance Fn in the first embodiment, but is about 40% of the grinding resistance Fn in the comparative example 1. The variation ratio Fn-AC · RMS of Example 1 is twice or more. That is, in Example 1, the fluctuation rate of the grinding resistance is smaller than that in Comparative Example 1, and the vibrating force for generating vibration on the offset grindstone is smaller.

Therefore, the offset grindstone of the first embodiment can suppress the generation of vibrations as compared with the offset grindstone of the first comparative example, and therefore, the machining surface accuracy is improved.

FIG. 4 is a diagram comparing spectra of vibration acceleration generated when granite is ground according to Example 1 and Comparative Example 1. In the same figure, the solid line shows the spectrum of Example 1, and the broken line shows the spectrum of Comparative Example 1. As shown in FIG. 4, in the high frequency range of 150 Hz or more, at the same frequency, the value of the vibration acceleration of Example 1 and the value of the vibration acceleration of Comparative Example 1 are almost the same. On the other hand, in the low frequency range of about 150 Hz or less, the value of the vibration acceleration of the first embodiment is smaller than the value of the vibration acceleration of the first comparative example at the same frequency. Hands and arms of the human body are insensitive to vibrations in the high frequency range, but are sensitive to vibrations in the low frequency range.

Therefore, when the granite is searched by the offset whetstone of the first embodiment, the vibration felt by the human body is smaller than when the granite is ground by the offset whetstone of the first comparative example, and human fatigue is reduced. be able to.

As described above, Example 1 is an offset whetstone in which the abrasive cloth 21 is attached to the back plate 22 corresponding to the offset whetstone 20 of the second embodiment. It is presumed that a similar result can be obtained also with the offset grindstone to which 11 is attached, that is, the offset grindstone 10 of the first embodiment.

[0024]

[Effect of the invention]

 According to the invention of claim 1, since the material of the back plate is glass fiber, when grinding a hard material such as a stone, the back plate absorbs the force that the abrasive grains receive from the hard material. For this reason, it is possible to suppress the occurrence of vibration on the offset grinding stone, thereby improving the machining surface accuracy. Moreover, since the energy in the low frequency region where the human body is sensitive can be reduced, the bodily sensation vibration of the operator is reduced, the fatigue is reduced, and the grinding work is facilitated. According to the invention of claim 2, since the material of the back plate is glass fiber, when grinding a hard material such as a stone material, the back plate absorbs a reaction force received by the abrasive cloth paper from the hard material. For this reason, the occurrence of vibrations in the offset grindstone can be suppressed, and the machining surface accuracy is improved. In addition, since the energy in the low frequency region where the human body is sensitive can be reduced, the bodily sensation vibration of the operator is reduced, the fatigue is reduced, and the grinding work is facilitated. .

[Brief description of the drawings]

FIG. 1 is a single view of an offset grindstone 10 according to a first embodiment, where (A) is a plan view and (B) is a cross-sectional view taken along line BB of (A).

FIGS. 2A and 2B are unit diagrams of the offset grinding wheel 20 of the second embodiment, wherein FIG. 2A is a plan view and FIG. 2B is a cross-sectional view taken along the line BB of FIG.

FIG. 3 is a table comparing the grinding resistance Fn when granite is ground according to Example 1 and Comparative Example 1.

FIG. 4 is a diagram comparing spectra of vibration acceleration generated when grinding granite according to Example 1 and Comparative Example 1.

FIG. 5 is a single view of a conventional offset whetstone 110,
(A) is a plan view, and (B) is a cross-sectional view taken along line BB of (A).

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Offset whetstone 11 Diamond whetstone 12 Back plate 20 Offset whetstone 21 Abrasive cloth 22 Back plate

Claims (2)

[Utility model registration claims] 1. An offset whetstone comprising a whetstone whose abrasive grains are diamond and a back plate to which the whetstone is attached, wherein the material of said back plate is glass fiber. 2. An offset grindstone comprising abrasive cloth paper whose abrasive particles are diamond, and a back plate to which the abrasive cloth paper is attached, wherein the material of the back plate is glass fiber. Offset whetstone.