JPS6116053Y2 - - Google Patents

Description

[Detailed description of the invention] This invention relates to the improvement of an electric knife sharpener that uses a battery or AC power source as a power source to rotate a grinding wheel at high speed to sharpen knives, scissors, and other cutlery. The shaft of the motor fixed inside the case is rotatably protruded from a shaft hole drilled in the upper wall of the main body case, and a grinding wheel is attached to the tip of the shaft. The purpose is to prevent the motor from entering the main body case through the shaft hole and damaging the motor's bearings, contacts, etc.

Examples of this invention will be described below with reference to the drawings.

1 is a main body case made of synthetic resin, and its upper wall 1a
A stepped recess 2 is provided in a part of the recess 2 , a shaft hole 3 is bored approximately in the center of the recess 2 , and the motor 4 is mounted so that the shaft 5 of the motor 4 protrudes from the shaft hole 3 . It is brought into contact with the inner surface of the recess 2 and fixed with a screw 6.

Reference numeral 7 denotes an annular sheet, which is molded from a synthetic resin such as acetal resin containing molybdenum disulfide, nylon resin, or polyethylene resin, and its shape is large enough to sufficiently close the shaft hole 3, as shown in FIG. The outer peripheral edge of this sheet 7 is tightly sealed from above by the shaft 5 so that it is in contact with the upper surface 2a of the recess 2 of the upper wall 1a or has a very small gap P (see FIG. 5).

To show a concrete sealed state, the inner diameter 7a of the annular sheet 7 is 2 as shown in FIGS. 3 and 5.
mm, outer diameter 7b is 5mm, thickness 7c is 0.05mm, shaft diameter 5a is 2.3mm, shaft hole diameter 3a is 2.5mm
5, the annular sheet 7 is deformed into a mountain shape as shown in FIG. It is in sliding contact with the upper surface 2a of.

8 is a grinding wheel mounting holder holding a grinding wheel 9 set in the space of the recess 2; 10 is the motor 4;
It is a cup-shaped coupling member fixed to the shaft 5 of the coupling member 10, and includes a shaft portion 11 formed on the coupling member 10, and a hollow shaft portion 12 formed on the holder 8 that is slidably fitted onto the shaft portion 11.
As shown in FIG. 2, engaging portions 13 and 14 are formed to prevent rotation of both 8 and 10, and between these two 8 and 10, the holder 8 is elastically supported so as to be movable up and down. A spring 15 is inserted.

Reference numerals 16 and 17 designate a plurality of pairs of downward connecting pieces arranged equally around the outer periphery of the holder 8;
The holder 8 and the coupling member 10 are connected to each other by engaging the engagement protrusion 18 protruding from the outer periphery of the coupling member 10.

19 is a battery as a power source for the motor 4, and 20 is a guide tool that guides the cutting direction of the cutting tool when the cutting tool is inserted.

The grinding wheel 9 is formed by compression molding or coagulation of alumina abrasive grains with a mesh number of 400 using an adhesive.

Conventionally, when grinding knives, scissors, etc., abrasive grains that have fallen off or chipped from the grinding wheel 9 are scattered around the grinding wheel 9, entering the main body case 1 through the shaft hole 3 and damaging the motor 4 and other grinding wheels. However, according to this invention, the shaft hole 3
is always blocked by the annular sheet 7, and since the annular sheet 7 is rotating, the abrasive grains that have fallen or accumulated on the sheet 7 are bounced outward, reducing the effect of blocking the shaft hole 3. This can be further encouraged.

Further, according to this invention, since the sheet 7 is tightly fitted into the shaft 5 from above, the sheet 7 deforms into a mountain shape. Although the above-mentioned closing effect is exhibited, even if the sheet 7 is tightly fitted in a position of the shaft 5 where only the outer end portion does not make sliding contact, the gap between the upper surface 2a of the recess 2 and the lower surface of the sheet 7 For example, in the above example, the gap P is the grain shape of the abrasive grains.
If the value is smaller than 30 um or 40 um, abrasive grains will not enter through the gap P. Furthermore, when the sheet 7 is deformed into a mountain shape, one edge of the inner periphery of the sheet 7 comes into close contact with the shaft 5, so the adhesion force per unit area to the shaft 5 is improved, and it rotates at high speed. Even when the shaft 5 moves, the sheet 7 can be reliably prevented from shifting.

In the above embodiment, the sheet 7 is formed into a disk shape, but when formed by press working, it can be formed into a square plate shape in consideration of material removal. Needless to say, it is possible given the size.

As described above, in this invention, the shaft 5 of the motor 4 fixed inside the main body case 1 is rotatably protruded from the shaft hole 3 bored in the upper wall 1a of the main body case 1, and the tip of the shaft 5 is In an electric knife sharpener equipped with a grinding wheel 9, an elastic annular sheet 7 having a size to close the shaft hole 3 and having an inner diameter smaller than the diameter of the shaft 5 is tightly attached to the shaft 5 from above. By fitting, the circular sheet 7 is deformed into a mountain shape,
One edge of the inner periphery of the sheet 7 is brought into close contact with the shaft 5, and the outer periphery of the sheet 7 is positioned so as to be in contact with the upper wall 1a or with only a small gap therebetween, so that no leakage into the shaft hole 3 can be achieved. In addition to being able to reliably prevent abrasive grains from entering, it is also possible to effectively prevent the sheet 7 from shifting during driving, and it is highly practical as it does not impose unnecessary load on the rotation of the shaft 5. .

[Brief explanation of the drawing]

Fig. 1 is a partially cutaway sectional view of an electric knife sharpener implementing this invention, Fig. 2 is an exploded perspective view of the main part of the same embodiment, and Fig. 3 is an external perspective view of the annular sheet used in the same embodiment. , FIG. 4 is an assembled partial cross-sectional view of the main part of the same embodiment, and FIG. 5 is a longitudinal cross-sectional view of the main part. 1...Body case, 1a...Top wall, 3...Shaft hole, 4...Motor, 5...Shaft, 7...
Sheet, 9... Grinding wheel.

Claims (1)

[Scope of utility model registration request] A shaft 5 of a motor 4 fixed inside the main body case 1 is rotatably protruded from a shaft hole 3 formed in the upper wall 1a of the main body case 1, and a grinding wheel 9 is attached to the tip of the shaft 5. In the type enclosing sharpener, an elastic annular sheet 7 which is large enough to close the shaft hole 3 and has an inner diameter smaller than the diameter of the shaft 5 is tightly fitted into the shaft 5 from above, thereby forming an annular sheet. 7 is deformed into a mountain shape, one edge of the inner periphery of the sheet 7 is brought into close contact with the shaft 5, and the sheet 7 is
An electric enclosing sharpener characterized in that the outer peripheral edge of the holder is positioned such that the outer peripheral edge thereof is in contact with the upper wall 1a or there is only a slight gap therebetween.