JPS5910822B2 - cutting tools - Google Patents

Description

[Detailed description of the invention] The present invention relates to cutting tools such as pliers and nimba.

Conventionally, with use of cutting tools such as pliers and tool tweezers, the engagement of the cutting edges of the blade body suddenly becomes loose, resulting in dull cutting ability.

This is because the pivot portion of the conventional cutting tool has a rivet 3 fitted into a straight hole 10, 20 formed in a pair of handles 1 and 2, as shown in FIG. 5, and the tip of the rivet is caulked.

Therefore, during cutting, the axial force of the rivet acting on the handles 1 and 2 is applied to the small area of the sloped surface 31 of the caulked part 30, causing premature wear of the sloped surface and unreasonable force. Occasionally, the caulking portion 30 occurs, causing play between the rivet 3 and the handle 1 or 2, causing the blade body (not shown) to be misaligned, resulting in a decrease in sharpness.

The present invention provides a cutting tool in which the engagement of the blade bodies is maintained in the best condition over a long period of time and the sharpness is not impaired by applying a special design to the pivot portion.

The present invention will be specifically described below based on embodiments shown in the drawings.

Although FIG. 1 shows a situation in which the present invention is applied to nippers, the present invention is not limited thereto, and it goes without saying that the invention can be applied to cutting tools such as pliers, radio pliers, and pliers.

As is well known, the nippers each have a blade body 11 facing inward at the tip.
A pair of handles 1 and 2 equipped with 21 are pivoted near the blade body.

The present invention is characterized in that the handles 1 and 2 are pivoted by a taper pin 4, and as shown in FIG. bundle 1,
Two large and small taper holes 12 and 22 with a very slight step 5 formed on the overlapping surfaces of the two taper holes 12 and 22 are opened on the same axis, and a taper pin 4 is driven into both taper holes 12 and 22 to form a small taper hole 22. and the taper pin 4 are tightly fitted and fixed, and the large taper hole 12 and the taper pin 4 are rotatably engaged.

In this embodiment, the slope of the taper holes 12 and 22 is about 1740, and the clear rank of the large taper hole 12 and the pin 4 is about o.
oo2mm.

Further, on the handle 2 on the small tapered hole 22 side, the opening edge at the tip of the small taper hole 22 is chamfered to form an inverted conical surface 23, and the taper pin 4 is caulked to engage with the inverted conical surface 23. The taper pin 4 is more strongly prevented from coming off.

Furthermore, an oil groove may be provided on the inner surface of the large taper hole 12 if necessary.

Various methods can be considered to form two large and small taper holes 12, 22 with the same slope, but for example, as shown in FIG. A stepped reamer 7 is passed through the stepped reamer 7 to form a stepped portion 5 on the overlapping surfaces of the upper and lower nozzles 1 and 2 as shown in FIG.

Or, as shown in Fig. 4, insert the thin plate 8 between the handles 1 and 2, pass it through a normal reamer 70, and then remove the thin plate 8.
When both handles 1 and 2 are overlapped, a step 5 similar to that shown in FIG. 2 can be formed.

In the present invention, as described above, the pair of nodles 1 and 2 are pivotally fixed by the taper pin 4, so that the one that rotates with a slight margin with respect to the pin, Since it is supported by the entire hole 12, there will be no play even if force is applied to the handle 1 in the axial direction of the tapered bottle, and therefore the blade bodies 11 and 21 will not become misaligned, and will remain sharp for a long time. Maintains sharpness.

Also, depending on the driving force of the taper pin 40, the pin 4
Since the clearance between the large taper hole 12 and the large taper hole 12 can be adjusted optimally, strict machining accuracy is not required for the hole diameter, and manufacturing is easy, which has many excellent effects.

[Brief explanation of the drawing]

Fig. 1 is an oblique view of the tip of the nipper, Fig. 2 is a sectional view of the pivot part, Figs. 3 and 4 are explanatory views showing the method of forming the taper hole, and Fig. 5 is a sectional view of the conventional example. It is. 1.2...handle, 11,21...blade body, 12.
...Large taper-TL22...Small taper one hole, 4...
Tehar pin, 5... step part.

Claims (1)

[Scope of Claims] 1. A cutting tool in which a pair of handles 1 and 2 each having blade bodies 11 and 21 formed at their tips are superimposed and pivotally fixed, and an item is sandwiched between the blade bodies 11 and 21 to cut the item. At , each handle 1, 2
Two taper holes 12 and 22, large and small, with the same slope and a very slight step 5 on the overlapping surfaces of the handles 1 and 2 are opened on the same axis in the pivot part of the 12,
22 has a Te, <- pin 4 is driven in, and a small taper hole 2 is inserted.
2 and the tip of the taper pin 4 are tightly fitted, and the large taper hole 12 and the large diameter portion of the taper pin 40 are rotatably engaged. 2. The cutting tool according to claim 1, wherein the tapered tip of the taper pin 4 is caulked. 3. The cutting tool according to claim 1 or 2, wherein the large taper hole 12 has an oil groove.