JPS5997856A - Hammer made of ceramic - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a hammer made of ceramic such as alumina, silicon carbide, silicon nitride, and zirconia.

Among the so-called hammers that have traditionally been used, such as the hammer and the geno, relatively high strength is required, and iron is often used for heavy items.

Such iron hammers have the advantage of being able to provide high striking strength at low cost, but on the other hand, they are not suitable for precision machinery or electronic T+.
When using a relatively small hammer made of iron, such as the one used for assembling or fine-tuning a 13N machine, there is a risk of generating sparks when it hits a ferrous metal, or causing magnetic changes. There was a risk of short-circuit accidents in electric circuits due to conductive materials.

On the other hand, in order to avoid damaging the surface being struck or causing sparks, it is made of a material that is softer than the object that makes up the surface being struck, such as copper, wood, synthetic resin, or rubber. Hammers were also used that matched the characteristics of each type. Therefore, hammers made of materials that are most suitable for the location where they are used or the object to be struck have been used, but there has not been a hammer that meets as many of the above requirements as possible.

The present invention aims to provide a new hammer developed in view of the above.

Hereinafter, to explain the hammer of the present invention in detail, as shown in FIG. ing. Among these, the head 2 that hits the object is made of a ceramic body such as alumina (81L0° silicon carbide (5iC), silicon nitride (5i3N4), zirconia (znO□), and sialon (Si381, 0.N9). However, the physical properties of these ceramic bodies are listed in Table 1.

Table 1 As is clear from Table 1, ceramic bodies generally have greater hardness than steel, but generally have lower bending strength and toughness. Among these, zirconia ceramic has a higher flexural strength than other ceramics, and in particular has extremely high fracture toughness, so it can be said to be the most suitable material for forming the hammer head 2.

By the way, even with the zirconia ceramics mentioned above, which have the highest fracture toughness, they are still inferior to those made of steel.
Since chipping is somewhat likely to occur, it is necessary and preferable that the bevel angle θ of a part of the corner in the cross section taken along line X-X in FIG. 1 be obtuse as shown in the partial cross section in FIG. Experimental results showed that when θ is 120 degrees or more, chipping and chipping hardly occur. In addition, the occurrence of chipping and chipping can be reduced by giving the product a rounded appearance as shown in the same figure (b).
In this case, a roundness size of 18 or more, preferably 2R or more was effective.

In the hammer shown in FIG. 1, the entire head 2 is made of ceramic; however, the hammer is not limited to this, as only the head 2 is shown in FIG. 3, the part that forms the striking surface. The ceramic member 2a may be arranged for the purpose, and the main body portion 2b may be made of metal or synthetic resin material.
Also, as shown in FIG. 2(b), one side has a ceramic member 2a.
On the other hand, in order to make the head 2 suitable for the object to be struck, a composite head may be constructed by combining head members 2C made of copper, rubber, wood, or the like.

As described above, according to the present invention, since at least the part forming the striking surface of the head is made of ceramic material, there is no magnetic or electrical adverse effect on the object to be struck, and there is The striking surface is polished to a mirror-like finish because it does not cause sparks, corrosion, or rust during assembly or inspection work on-site, and the striking surface is highly hard, making it difficult to wear or scratch. By being
For example, when the hammer is used to spread gold to make gold leaf or to make arts and crafts, it is possible to provide a hammer that has many features such as no risk of damaging the surface of the workpiece.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing a ceramic hammer according to an embodiment of the present invention, and FIGS. 2(A) and 2(B) are X-X in FIG.
Figures 3(a) and 3(b) show partial cross-sectional views along the line.
) is a side view showing another example of only the head constituting the ceramic hammer according to the present invention. 1: Handle 2: Head 5 = Figure 2 (4) (0) Figure 3

Claims (1)

[Claims] A ceramic hammer characterized in that at least a portion forming a striking surface is made of a ceramic such as alumina, silicon carbide, silicon nitride, zirconia, or sialon.