JPS629016Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an improved replaceable hammer that prevents the replacement head from falling off.

As a replaceable hammer whose head can be replaced, a circular hole is provided on both end surfaces of the hammer body, and a cylindrical projection provided on one side of the replacement head is fitted into the circular hole, and Replaceable hammers that are fixed with screws are known. However, with this hammer, it is difficult to align the screw holes provided in the hammer body and the protrusion, and during use, the threads of the screws may loosen due to wear and the holes may become misaligned. Also, a method has been devised in which the fitting surface is tapered and screws are omitted, but this method does not guarantee that the head will not fall off.

The present invention provides an improved replaceable hammer equipped with a device that reliably prevents the head of the replaceable hammer from falling off.

Figure 1 of the drawings is a sectional view including the axis of the plane (viewed from the direction of the handle) of the left half of the hammer of the present invention excluding the handle (the right half is omitted because the left and right sides are the same); The figure is a cross-sectional view taken in the right angle direction of Figure 1 (stops are omitted), and Figure 3 is a cross-sectional view of Figure 1.
FIG. 3 is a cross-sectional view taken along line A-A in the figure. The designating numerals in each drawing are common.

A circular hole 2 is opened in the end face of the hammer body 1, and a cylindrical projection 4 is formed in the center of one side of the refill head 3. Preferably, the inner circumferential wall surface of the circular hole 2 and the outer circumferential surface of the protrusion 4 are tapered to widen outward from the opening. A screw 5 is screwed into the center of the end face of the protrusion 4. A through hole 6 is bored at the bottom of the circular hole 2 in the main body. A stopper 7 made of piano wire is installed through this through hole 6. 8
is the hole for attaching the handle. As shown in FIG. 3, the head 7' of the stopper 7 has a larger size, so that when the stopper 7 is inserted into the through hole 6,
This portion is adapted to fit over the end of the through hole. After inserting the stopper 7, bend its tip as shown at 7'' and fix it at the entrance on the opposite side of the through hole 6.The stopper 7 is inserted into the center of the bottom of the circular hole 2, as shown in FIG. In other words, it has a shape that stands out from the bottom surface at the position where the replacement head screw is present.It is convenient to provide cutout grooves for mounting the fasteners 7 at both open ends of the through hole 6.

When the protrusion 4 of the replacement head is pushed into the circular hole 2 after the stopper 7 is installed, the screw head pushes the stopper 7 apart and passes through, and after the stopper 7 passes through the screw head, its elasticity tightens the leg of the screw. The state shown in FIG. 3 (for convenience, the stopper 7 is shown as a flat surface) is reached, and the replacement head 3 will not come off because the head of the screw is held by the stopper.

When it is necessary to remove the replacement head 3, it is easy to do so by straightening the bend in the tip 7'' of the stopper 7, pulling out the part 7' using pliers, etc., and then driving a removal pin into the through hole 6. You can remove the head instead.

The dimensions of each part are not critical; the material, strength,
It can be determined appropriately by considering the size of the hammer, etc. As for the curved dimensions, the inner width of the stopper 7 is approximately 3 to 6 mm (this is equal to the diameter of the leg of the screw).
The diameter of the screw head is slightly larger than this (approximately 6 to 9 mm). The stopper 7 is manufactured from piano wire with a diameter of about 1.0 mm.

The diameter of the through hole 6 is approximately 5 to 10 mm.

[Brief explanation of drawings]

FIG. 1 is a plan sectional view of the left half of the hammer of the present invention, and FIG. 2 is a front sectional view of the same.
FIG. 3 is a cross-sectional view of the section AA in FIG. 1.

Claims (1)

[Scope of utility model registration request] In a replaceable hammer in which the hammer body has a circular hole at the center of both end faces thereof, and a cylindrical projection of a replacement head of the hammer is fitted into the circular hole, the circular hole of the hammer body has a circular hole. An improved replaceable hammer comprising: a stopper having the shape shown in the drawing attached to the bottom; a screw screwed into the end face of the protrusion of the replacement head; and the screw being clamped and fixed by the stopper.