JPH0487780A - Grindstone - Google Patents

Abstract

PURPOSE:To obtain good sharpness of scissors by forming a polishing action surface of a grindstone in a curved surface almost suited for the edge bottom surface of an edge body of the scissors. CONSTITUTION:A polishing action surface 12 of predetermined width is formed into a curved surface of circular arc-shaped section, in the lengthwise direction, and relating to one end peripheral edge 13a, by which a circular arc of predetermined radius of curvature of the curved surface is formed, the other end peripheral edge 13b, by which a circular arc of the curved surface is formed, is formed such that the polishing action surface 12 in the advanced position is tilted by increasing each predetermined angle relating to a horizontal surface according to the other end peripheral edge advanced a predetermined distance in one direction, so that the curved surface is spirally twisted. In this way, the reverse side of an edge body 21 can be polished without eliminating a twist of an edge bottom surface 23 of the edge body 21 simultaneously keeping sharpness of an edge point part of wedge-shaped section in the edge body of scissors, and good sharpness thereof can be ensured.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a stone, and more specifically, it is an object of the present invention to provide a stone suitable for polishing the bottom surface provided on the back side of the blade of scissors. be.

[Prior art] First, regarding the shape of the blade of scissors used for hairdressing, etc.
This will be explained using FIG. Here, FIG. 2 is a cross-sectional view of the blade of the scissors in the width direction, and for simplicity of explanation, only one of the two blades is shown.

In FIG. 2, the back surface of the blade 21 is provided with a hollow surface 23 that forms an arc-shaped recess. By forming this, it is necessary that the cutting edge portion 22 of the blade 21, which has a wedge-shaped cross section, is sharp. The radius of curvature of this bottom surface 23 is generally 110 mm.

Also, blade 2! The blade is twisted from its base to its tip toward the other blade, forming an extremely gentle spiral shape. For this purpose, the bottom surface 23 provided on the back surface of the blade 21 also forms a twist. The twist of the bottom surface 23 and the blade 21 is an important element for obtaining good sharpness of the scissors. Therefore, when the scissors become dull and the surface side of the blade 21 is polished, the blade edge 22 gradually wears out and the blade 2I
As a result, the width of the blade 21 becomes narrower, the recess of the bottom surface 23 on the back side becomes shallower, the cutting edge part 22 having a wedge-shaped cross section loses its sharpness, and the front side of the cutting edge 21 becomes narrower in the width direction. By polishing the cutting edge portion 22 so as to move backward, the tips of the cutting edge portions of the two blades are worn away from each other in the thickness direction, so that the contact pressure between the two blades also decreases. Therefore, it was not possible to obtain a good sharpness with the scissors.

Therefore, conventionally, various types of stones have been used to polish the back surface of the blade 2I in order to ensure a recess in the bottom surface 23 of the blade 21.

FIG. 3A shows the configuration of such conventional example 1, in which (1) is a side view and (b) is a front view. In this prior art example 1, as shown in the figure, the polishing surface 32 of the stone 31 is formed into a flat surface. In this case, the blade of the scissors is 2+ due to the stone 31.
When the bottom surface 23 of (Fig. 2) is polished, the back surface of the cutting edge portion 22 of the blade 21 is worn away at the part indicated by the broken line, and becomes partially horizontal and flat, as shown in Fig. 3B. .

FIG. 4A shows the configuration of Conventional Example 2, in which (a) is a side view and (b) is a front view. Here, as shown in (a), the polishing surface 42 of the stone 41 forms a gentle arc-shaped curved surface, and the radius of curvature of the curved surface is, for example, 8.
A large value such as 00 mm is generally used. When the bottom surface 23 of the scissor blade 21 (FIG. 2) is polished using the abrasive stone 4I whose polishing surface 42 is a gently curved surface, the cutting edge of the blade 21 is polished as shown in FIG. 4B. Part 22
The inclination of the back surface with respect to the horizontal plane is extremely gentle compared to the original bottom surface 23 shown by the broken line.

FIG. 5 shows the configuration of Conventional Example 3, in which (a) is a side view and (b) is a front view. Conventional example 3 here
In this case, the polishing surface 52 of the stone 51 is made into a very gentle spherical shape with a radius of curvature larger than the radius of curvature of the polishing surface 42 in the conventional example 2 shown in FIG. 4A. Bottom surface 23 of the scissor blade 21 (Figure 2)
When polished, the inclination of the back surface of the cutting edge portion 22 of the blade 21 with respect to the horizontal plane becomes extremely gentle, as in the case of Conventional Example 2 described using FIG. 4B.

[Problems to be Solved by the Invention] According to Conventional Example 1, since the polishing surface 32 of the stone 31 (FIG. 3A) is flat, as shown in FIG. 3B,
As a result of the back surface of the cutting edge portion 22 of the scissor blade 21 (FIG. 2) being polished into a flat surface, the cutting edge portion 22, which has a wedge-shaped cross section, loses its sharpness, making it difficult to obtain good sharpness of the scissors. Moreover, when the stone 31 is used to repeatedly polish the bottom surface 23 of the scissors blade 21, the flat polished surface gradually expands and the contact surface between the two blades increases, making the operation of the scissors difficult. There was an issue that needed to be resolved, as it made hairdressing difficult.

J, conventional example 2? Koyoru Tostone 41 (4th AEI)
The radius of curvature of the polishing surface 42 is the same as the bottom surface 23 of the blade 21.
As shown in FIG. 4B, the cutting edge portion 22 with a wedge-shaped cross section is extremely larger than the radius of curvature of the conventional #J I
Similarly, the scissors lose their sharpness, making it difficult to maintain good cutting ability. Furthermore, since the polishing surface 42 is simply arcuate in cross section in the longitudinal direction, it is suitable for polishing along the bottom surface 23 of the blade 21, which forms a gentle spiral twist. Not there,
There has been an unresolved problem that the twist of the bottom surface 23 disappears when polishing is repeated.

Furthermore, in Conventional Example 3, since the polishing surface 52 of the stone 51 (FIG. 5A) has a spherical shape with a radius of curvature much larger than the radius of curvature of the bottom surface 23, it is similar to that described for Conventional Example 2. Another problem that needs to be solved is that the cutting edge portion 22, which has a wedge-shaped cross section, loses its sharpness, making it difficult to obtain good sharpness from the scissors.

In addition, each conventional example 1.2.3. The width of each polishing surface 32, 42, 52 is narrow, about 40 mm, and therefore the back surface of the part of the blade 21 where the cutting edge part 22 is provided, and both blades are pivoted. The joint surface of the two blades around the spindle that rotates one blade must be polished separately, and as a result, a step is formed between the two blades, making it difficult for the scissors to run smoothly. There was also an unresolved issue that it was not possible to obtain proper operation.

``Means for Solving the Problems'' The present invention has been made in light of the above-mentioned problems, and as a means of solving the problems, the polishing surface of a predetermined width is formed in a long horizontal direction that almost matches the bottom surface of the scissors. A configuration was used in which the curved surface had an arcuate cross section and the curved surface was twisted into a gentle spiral shape.

[Function] With this configuration, the back surface of the scissor blade can be polished without losing the sharpness of the cutting edge, which has a wedge-shaped cross section, and at the same time, without eliminating the twist on the bottom surface of the blade. This makes it possible to ensure good sharpness of the scissors.

[Embodiment] The structure of an embodiment of the present invention is shown and explained in FIGS. 18 to 1D.

FIG. 1A shows the outer shape of a stone according to the invention;
(a) is a perspective view, (b) is a side view, and (c) is a front view. In Figure 1A, stone 1! The width of the polishing surface I2 is 75 mm, and the polishing surface I2 forms a curved surface with an arc-shaped cross section in the longitudinal direction, and the radius of curvature of the peripheral edge 13a forming an arc at one end of this curved surface is 150 mm. With respect to the arc-shaped peripheral edge 13b at the other end, every time the peripheral edge 13b advances 10 mm from the edge 14a in the direction of the edge 14b, the polishing surface 12 at the advanced position is 0.5 mm with respect to the horizontal surface. The polishing surface 12 is made into a curved surface that is gently twisted in a spiral by increasing the angle of inclination.

Polishing surface 1 with such a spiral groove
2 will be explained in more detail using FIGS. 1B to 1D. FIG. 1B is a cross-sectional view of the first Affl(b) along line A-A, and shows the polishing surface 12 (
1A) has a slight angle with respect to the horizontal plane H indicated by a dashed line.

FIG. 1C is a sectional view taken along the line B--B in FIG. 1A(b), and the polishing surface 12 is inclined with respect to the horizontal plane H at a larger angle than that shown in FIG. 1B. 1st
FIG. D is a cross-sectional view taken along the line CC in FIG. 1A(b), and is inclined at an even larger angle than that shown in FIG. 1C.

In this way, along the peripheral edge 13b, the edge 1 is lower than the edge 14a.
4b, the inclination of the polishing surface 12 with respect to the horizontal plane at the advanced position is 10 m as described above.
It increases by 05° every m, so for example, the edge 14
When proceeding 100 mm from a, the polishing surface 12 at that position
The inclination of is 5° with respect to the horizontal plane.

Here, since the radius of curvature of the bottom surface 23 of the scissors blade 21 (FIG. 2) is generally 1Q mm as described above, if the radius of curvature of the peripheral edge 13a is also the same 110 mm, then the polishing surface 12 The fins are completely in close contact with the bottom surface 23. However, if the polishing surface 12 and the bottom surface 23 are brought into complete contact, the contact surface between the two becomes large, which requires more labor for the polishing operation. It is not possible to feel the contact with 2, which makes polishing even more difficult. Therefore, it is preferable that the radius of curvature of the peripheral edge 3a is somewhat larger than the radius of curvature of the bottom surface 23 so that a gap is created between the polishing surface 12 and the bottom surface 23. Therefore, in the present invention, the radius of curvature of the peripheral edge 13a is set to 110, which is the general radius of curvature of the bottom surface 23.
mm, and in this example, it is 1 mm.
It was set to 50 mm.

FIG. 1E shows the state of the cutting edge portion 22 when the back surface of the scissors is polished using a stone according to the present invention, and the radius of curvature of the peripheral edge 13a of the polishing surface 12 is the same as that of the conventional example 2 described above. 3
, the worn portion of the bottom surface 23 shown by the broken line is minute because the radius of curvature is close to that of the bottom surface 23. As a result, the cutting edge portion 22 of the blade 21, which has a wedge-shaped cross section, does not lose its sharpness, and the scissors can provide good sharpness.

In addition, since the polishing surface 12 is twisted to correspond to the twist of the bottom surface 23, the twist of the bottom surface 23 can be maintained, and good sharpness of the scissors can be ensured from this surface as well. I can do it.

[Effects of the Invention] As explained above, according to the present invention, the abrasive surface of the stone is made to be a curved surface that almost matches the bottom surface of the blade of the scissors, so that the cutting edge of the blade, which has a wedge-shaped cross section, The sharpness is not lost, and the polishing surface is formed to have a twist that corresponds to the twist of the bottom surface, which prevents the bottom surface from disappearing by polishing the back side of the blade, resulting in a good quality scissors. You can get sharpness. In addition, since the width of the polishing surface is wider than before, the back side of the part of the blade where the cutting edge is provided and the two blades are joined around the spindle for rotating one blade. Since both surfaces can be polished at the same time, there is no difference in level between the two, allowing smooth operation of the scissors. Therefore, according to the present invention, significant practical effects can be obtained.

[Brief explanation of the drawing]

FIG. 1A is a configuration diagram of one embodiment of the present invention, and FIG. 1B is a first embodiment of the present invention.
Figure 1C is a cross-sectional view taken along line A-A in Figure 1A (b), Figure 1D is a cross-sectional view taken along line B-B in Figure 1A (b), Figure 1D is line C-C in Figure 1A (b). Figure 1E is a cross-sectional view of the scissors blade polished by the stone shown in Figure 1A, and Figure 2 is a cross-sectional view of the blade of the scissors shown in Figure 1A. FIG. 3A is a cross-sectional view of the blade in the width direction, FIG. 3A is a configuration diagram of Conventional Example 1, and FIG. 3B is a diagram of the cutting edge of the scissors polished by Conventional Example 1 shown in FIG. 3A. An enlarged sectional view, FIG. 4A is a configuration diagram of conventional example 2, FIG. 4B is an enlarged sectional view of the cutting edge of the tanu blade, illustrating the blade of the scissors polished by conventional example 2 shown in FIG. 4A, FIG. 5 is a configuration diagram of conventional example 3. 11.31.41.51...and stones 12.32.42.52...polishing surfaces 13a, 13b
- Peripheral edges 14a, 14b, one end edge 21...blade 22...blade tip 23...bottom surface. (a) Agent 1) Kozo (and 1 other person) (b) (e) Figure 1A horizontal plane H Figure 1B Figure 1C Figure 1D bottom surface 23 Figure 2 31 and stones (a) (b) Figure 3A Figure 3B (a) (b) Figure 4A (a) (b) Figure 5

Claims (1)

[Scope of Claims] 1. The polishing surface (12) with a predetermined width is a curved surface having an arc-shaped cross section in the longitudinal direction, and the periphery (13a) of one end of the curved surface forming an arc with a predetermined radius of curvature is As the circumferential edge (13b) of the other end forming an arc of the curved surface advances a predetermined distance in one direction along the circumferential edge of the other end, the polishing surface at the advanced position increases by a predetermined angle with respect to the horizontal plane. The stone is characterized by being formed so that the curved surface is twisted in a spiral shape. 2. The width of the polishing surface is 65 to 85 mm, and the radius of curvature of one end of the arc of the curved surface is 120 to 85 mm.
200 mm, and as the peripheral edge of the other end of the arc of the curved surface advances 10 mm in one direction, the polishing surface at the advanced position is 0.3 to 0.8 with respect to the horizontal surface.
2. The abutment stone according to claim 1, which is inclined in increments of .degree.