JPH0340511Y2 - - Google Patents

Description

[Detailed description of the invention] (Field of industrial application) This invention is a cutting tool for threaded rod cutters that can cut threaded rods without crushing the threads, and that does not cause the thread itself to chip when cutting. It's about the blade.

(Prior art) Threaded rod cutters, commonly known as threaded bolts in the industry, are used to cut threaded rods to a desired length at construction sites, etc., and are equipped with a threaded rod cutter that is used to cut threaded rods to a desired length at construction sites. A cutting blade for a threaded rod cutter is used that has a thread carved into the inner circumferential surface. However, as shown in FIG. 5, the conventional cutting blade 40 for a threaded rod cutter has a female thread 41 with the same thread shape as the male thread 51 of the threaded rod 50 to be cut on the inner peripheral surface. , when cutting, the two are in close contact over almost the entire surface, and the male thread 51 of the threaded rod 50 is connected to the female thread 4.
1 into a wedge shape, and presses outward the incomplete chevron portion 42 that inevitably occurs on either end face of the threaded rod cutter cutting blade 40 to prevent screw chipping 4 during use.
There was a drawback that 3 was likely to occur.

Therefore, the inventor of the present invention made the width of the trough of the female thread carved on the cutting blade wider than the thread of the male thread of the threaded rod, so that the top of the thread of the threaded rod could be aligned with the trough of the female thread of the cutting blade. He devised a cutting blade for a threaded rod cutter that would come into contact with the blade, and proposed it earlier as Utility Model Application No. 61-92516, but subsequent experiments showed that the threaded rod had a larger diameter and the cutting load increased. It has been found that over time, the threads are crushed and the side surfaces of the incomplete ridges are pressed, resulting in chipping.

(Problems to be solved by the invention) The present invention solves the above-mentioned conventional problems and creates a screw that does not cause thread breakage at the incomplete chevron portion even when cutting a large-diameter threaded rod. It was developed to be used as a cutting blade for bar cutters.

(Means for solving the problem) The present invention provides a cutting blade for a threaded rod cutter in which a female thread corresponding to the male thread of the threaded rod is carved on the inner circumferential surface in contact with the threaded rod to be cut. The bottom of the threaded rod is wider than the thread of the threaded rod, and the incomplete ridge-shaped portion that inevitably occurs at the end face of the threaded rod is thickened.

(Function) For example, as shown in FIG.
It is used by attaching the other end to a movable platen 13 which is rotated by an arm rod 11 via a link 12, and the threaded rod is connected between the inner circumferential surfaces on which a female thread corresponding to the male thread is carved. Shearing without pinching and crushing the threads is the same as in the past. However, in the cutting blade of the present invention, as mentioned above, the trough is wider than the thread of the threaded rod, so the thread of the threaded rod hits the trough of the female thread of the cutting blade and is sheared at the trough. In addition to supporting the load, the incomplete chevrons that inevitably occur on either end face are thickened, so when cutting a large diameter threaded rod, the threads are crushed and the cutting blade is damaged. Even if the side surface of the incomplete chevron portion on the end face is strongly pressed, the imperfect chevron portion is less likely to crack or chip, and has the advantage that even large-diameter threaded rods can be cut with confidence.

(Embodiment) Next, the present invention will be described in detail with reference to the illustrated embodiment. In the first embodiment shown in FIGS. 1 and 2, A and B are a pair of screws for cutting a threaded rod 50. It is a cutting blade for a rod cutter, and it is a threaded rod 5.
Female threads 1 having the same pitch as the male threads 51 of the threaded rod 50 are carved on the inner circumferential surface in contact with the threaded rod 50. As shown in the figure, the female thread 1 has its trough 2 wider than the thread of the threaded rod 50, and the height of the thread is smaller than the height of the thread of the threaded rod, so that it can be cut easily as shown in the figure. The threaded rod 50 is formed so that the threaded top 52 comes into contact with the root of the female thread 1 as shown in FIG. Such a pair of cutting blades for threaded rod cutters inevitably have incomplete chevron portions 3 formed on their end faces, but in this embodiment, the pitch of the female thread 1 is the same as the pitch of the threaded rod 50. By shifting only the phase while maintaining the same angle, the thickness of the incomplete chevron portion 3 is increased by the amount shown as C in FIG. 1. The dimension that can be thickened is limited by the width dimension of the root of the female thread 1, but it is 10 to 15 of the pitch of the male thread 51 of the threaded rod 50.
It is desirable to set it to about %. If the thickness is too thick, the cutting position of the threaded rod 50 will be on the slope of the thread, and "burrs" will easily occur during cutting, making it necessary to correct the thread after cutting. Similarly, if the width of the root of the female thread 1 of the cutting blade is made too wide, the ridges of the male thread 51 of the threaded rod 50 will be easily crushed, and the effective diameter of the thread will become like a thick thread, making it difficult to screw into a nut, etc. becomes difficult. Note that the thickened incomplete chevron portion 3 may be provided only on one side, which becomes the shearing surface.
If both sides are thickened, the opposite side can also be used, which is convenient.

Next, in the second embodiment shown in FIG. 3, the thickness of the cutting blades A and B is N times the pitch of the male thread 51 of the threaded rod 50, and the pitch of the female thread 1 of the cutting blades A and B is set to the same value. By setting the pitch smaller than the pitch of the male thread 51, the end faces of the cutting blades A and B are thickened by the amount shown as C. In this case as well, it is preferable to set the pitch of the female thread 1 so that the degree of thickening is 10 to 15% of the pitch of the male thread 51 of the threaded rod 50, as in the first embodiment. In addition, as shown in the figure, the thickness of the cutting blade A that is on the completely chevron side is N times the pitch of the female thread 1, and the thickness of the cutting blade B that is on the incomplete chevron side is thinner than the thickness of the cutting blade A. If it is increased by the amount of heat, the strength can be improved more fully.

(Effect of the invention) As is clear from the above explanation, the invention makes the root of the female thread of the cutting blade wider than the thread of the threaded rod so that the shear load is supported by the root of the female thread of the cutting blade. At the same time, since the imperfect chevron part has been made thicker, even if the imperfect chevron part on the end face of the cutting blade is strongly pressed when cutting a large diameter threaded rod, etc., the imperfect chevron part is less likely to crack or chip. , it can easily cut even large-diameter threaded rods. Further, the cutting blade of the second embodiment is compatible with the cutting blade of the previously proposed Japanese Utility Model Application No. 61-92516. Therefore, the present invention has extremely great practical value as it solves the conventional problems.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing a first embodiment of the present invention;
FIG. 2 is a side view thereof, FIG. 3 is a sectional view showing a second embodiment of the present invention, FIG. 4 is a front view showing a state of use, and FIG. 5 is a sectional view showing a conventional example. 1: Female thread, 2: Valley, 3: Incomplete chevron, 5
0: Threaded rod, 51: Male thread.

Claims (1)

[Scope of utility model registration request] In a cutting blade for a threaded rod cutter, which has a female thread 1 corresponding to the male thread 51 of the threaded rod 50 engraved on the inner peripheral surface in contact with the threaded rod 50 to be cut, the bottom of the female thread 1 of the cutting blade is connected to the thread of the threaded rod 50. A cutting blade for a threaded rod cutter, characterized in that the width is wider than the ridge, and the incomplete ridge portion 3 that inevitably occurs at the end face of the blade is thickened.