JP2526698Y2 - One-touch attaching / detaching device for whetstone - Google Patents

Description

[Detailed description of the invention]

[0001]

The present invention relates to a grinding wheel having a small diameter (for example, a diameter of 125 mm or less) and a low rotation speed (4,000 rpm).
m or less, a peripheral speed of 1000 m / min or less).

[0002]

2. Description of the Related Art Conventionally, various one-touch type attachment / detachment devices for an input boss connected to a motor output shaft of a hand polisher and a grinding wheel holder have been proposed (for example, Japanese Utility Model Application Laid-Open No. 58-158).
-55845, 58-8562, 62-806
3). However, since they hold the fitted state by the friction of the fitting portion between the input boss and the grindstone holder and the friction of the elastic ring disposed therebetween, the holding force is small,
Easy to come off. Also, the diameter of the fitting portion using the square shaft is
Since it is slightly larger than the output shaft, wear and noise increase due to torsional vibration and the like generated at the time of transmission of rotational force. The centering action for maintaining the center is small, and the surface is easily affected by vibration. Further, the distance from the root of the output shaft (the length in the axial direction) is increased, and the operability is likely to be deteriorated.

[0003]

The object of the present invention is to increase the holding force of the fitting joint between the input boss and the grindstone holder so as to prevent the input boss from coming off, to prevent wear and noise due to torsional vibration, etc., and to extend the centering function. The purpose is to be able to maintain the period stably, to shorten the axial length, and the like.

[0004]

The present invention comprises an input boss having a flange portion larger in diameter than the input boss portion below the input boss portion, and a grindstone holder having a grindstone on the lower surface and having substantially the same diameter as the flange portion. A square shaft provided on one of the outer periphery of the flange portion of the input boss and the outer periphery of the grindstone holder is fitted into a square hole provided on the other to enable transmission of rotational force, and a washer at the center of the bottom surface of the square hole. Or, the central portion of the disc spring having a diameter slightly smaller than the square shaft portion is fixed to the washer-shaped projection while normally facing the square shaft portion, and a plurality of claw pieces protruding toward the square shaft portion on the outer peripheral portion of the disc spring. A circular concave portion in which the claw is fitted to the square shaft portion and the tip of the claw bites is formed only when the disc spring is warped in the reverse direction. .

[0005]

1 shows a state in which an input boss 1 and a grindstone holder 2 are separated from each other, FIG. 2 shows a fitted state, and FIG. 3 is an exploded view. The input boss 1 has a cylindrical input boss portion 7 having a screw hole 6 into which the screw portion 4 at the lower end of the motor output shaft 3 is screwed to the step portion 5, and a hexagonal plate-like shape as viewed in plan. Square shaft part 8
Are integrally provided with a square hole portion 14 to be fitted thereinto and a flange portion 9 including a screw hole 15 at the center thereof.

On the bottom surface 19 of the square hole 14, a thick washer 2
0, a disc spring 21 made of a spring steel plate, and a thin washer 22 are fastened by screwing the bolt 11 into the screw hole 15. The Belleville spring 21 is generally spherically recessed toward the outlet of the square hole, and a number of claw pieces 23 are formed by bending around the circumference, and the claw pieces 23 are arranged in a low cylindrical shape as a whole. The disc spring 21 has a diameter capable of fitting into the circular recess 10 with a slight gap, and the height of the claw 23 is substantially equal to the depth of the circular recess 10 (the height of the inner peripheral surface 13). Reference numeral 24 denotes a central hole of the disc spring 21. Instead of the washer 20, a washer-like projection may be provided on the bottom surface 19.

The grindstone holder 2 has a hexagonal plate-shaped hexagonal square shaft portion 8 on the upper surface as viewed in plan. A shallow circular concave portion 10 is provided on the upper surface of the square shaft portion 8, and an inner peripheral surface 13 thereof is provided.
Has a taper angle (e.g., 10 degrees) whose diameter increases toward the back (downward). A hole 12 is provided in the center of the bolt 11 to allow the head of the bolt 11 to escape. Whetstone holder-2
Is provided with a centering boss 17 into which a central hole of a disc-shaped grinding wheel 16 is fitted.
8 are connected. As the grindstone 16, a grindstone mainly using diamond abrasive grains, a general abrasive grain grindstone or the like is used. The grindstone holder 2 and the input boss 1 can be formed of metal or resin as a structural material.

As shown in FIG. 1, a square hole 14 of the input boss 1 attached to the output shaft 3 of the hand polisher is fitted into the square shaft 8 of the grinding wheel holder 2 to which the grinding stone 16 is connected. A disc spring 21 is assembled to the input boss 1. When the input boss 1 is pressed down and fitted in this state, the claw 23 is pushed up by the bottom surface of the circular concave portion 10, and the periphery of the disc spring 21 is upward through a flat state. At the same time, each claw piece 23 has its leading edge protruding outward in the radial direction and bites into the lower end face at the back of the inner peripheral surface 13.

During the polishing of the work material, the rotational force is transmitted from the input boss 1 to the grindstone holder 2 by the engagement between the square shaft 8 and the square hole 14.
Is transmitted to the grindstone 16. When replacing the grindstone 16 with another grindstone, the grindstone holder 2 is pulled downward with respect to the input boss 1. Then, the disc spring 21 is expanded as shown in FIG.
Returns to the original downward-opening position through the flat state, and the claw pieces 23
Are separated from the inner peripheral surface 13 and are aligned in a cylindrical shape, and come out of the circular concave portion 10 upward. Continue with a whetstone holder with another whetstone
The input boss 1 is fitted to the upper part 2 from above.

FIG. 4 shows a state in which a square shaft portion 8 is formed on the flange portion 9 of the input boss 1 and a disc spring 21 is attached to the grindstone holder 2 in an upwardly open position. With this configuration, the same effect as the present invention can be obtained.

[0011]

According to the present invention, since the grindstone 16 and the grindstone holder 2 are held on the input boss 1 by the disc spring 21 having a diameter slightly smaller than that of the input boss 1, the holding force is increased, and there is a possibility that the whetstone 16 may come off during the work. Therefore, cracking of the grindstone and damage to the surface of the stone material, ceramics and the like are eliminated. In addition, the center is securely maintained, and the claw piece 23 elastically bites on the inner peripheral surface 13, so that the torsion vibration is absorbed by the claw piece 23 and the vibration noise caused by the collision between the square shaft portion 8 and the square hole portion 14 is reduced. There is an advantage that can be prevented. Since the diameters of the square shaft portion 8 and the square hole portion 14 are sufficiently large, power transmission is ensured, wear of the fitting connection portion is reduced, and the diameter of the disc spring 21 incorporated therein can be easily increased.
As described above, the dimension in the axial direction can be reduced while maintaining a large holding force, and operability is improved. Inner circumference 1
When the taper angle A is provided in 3, the effect of increasing the holding force is further improved. It is easy to put on and take off.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a part of a cross section before coupling.

FIG. 2 is a partial longitudinal sectional view showing a connected state.

FIG. 3 is an exploded perspective view.

FIG. 4 is an exploded perspective view showing another embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Input boss 2 Grindstone holder 7 Input boss part 8 Square shaft part 9 Flange part 10 Circular concave part 13 Inner peripheral surface 14 Square hole part 16 Grindstone 19 Bottom 20 Washer 21 Disc spring 23 Nail piece

Claims (2)

(57) [Scope of request for utility model registration] An input boss having a flange below the input boss having a diameter larger than that of the input boss; and a grindstone holder having a grindstone on the lower surface and having substantially the same diameter as the flange. A square shaft provided on one of the outer periphery of the flange portion and the outer periphery of the grindstone holder is fitted into a square hole provided on the other to enable transmission of rotational force, and a washer or washer at the center of the bottom surface of the square hole. The projection is usually oriented toward the square shaft, and the center of the disc spring with a slightly smaller diameter is fixed and the outer periphery of the disc spring is provided with a number of claw pieces protruding toward the square shaft, A one-touch whetstone attachment / detachment device for a whetstone, wherein a circular concave portion is formed in the square shaft portion such that the tip of the claw bites only when the claw piece is fitted and the disc spring warps in the opposite direction. 2. The one-touch attaching / detaching apparatus for a grindstone according to claim 1, further comprising a taper whose diameter becomes larger as the inner peripheral surface of the circular concave portion goes deeper.