JPH028659Y2 - - 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. 7, the conventional cutting blade 40 for a threaded rod cutter has a female thread 41 having 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-shaped 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.

(Problems to be solved by the invention) The present invention solves the above-mentioned conventional problems and can cut threaded rods without crushing the threads. It was completed with the aim of creating a cutting blade for threaded rod cutters that does not cause thread chipping on the angled portion.

(Means for solving the problem) The present invention provides a cutting blade for a threaded rod cutter in which a female thread of the same pitch as the male thread of the threaded rod is carved on the inner circumferential surface in contact with the threaded rod to be cut. By making the trough of the thread wider than the thread of the threaded rod, and making the height of the thread of the female thread smaller than the height of the thread of the threaded rod, the top of the thread of the threaded rod is made wider than the thread of the female thread. It is characterized in that it comes into contact with the bottom of the valley.

(Embodiment) Next, the present invention will be described in detail with reference to the illustrated embodiment. In FIGS. 1 and 2, A and B are a pair of cutting blades for a threaded rod cutter for cutting a threaded rod 50, On the inner peripheral surface in contact with the threaded rod 50, female threads 1 of the same pitch as the male threads 51 of the threaded rod 50 are carved. 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 crest 52 comes into contact with the root 3 of the female thread 1 as shown in FIG. In order to manufacture such cutting blades A and B for threaded rod cutters, as shown in FIGS. 3 and 4, the threaded rod 5 is
Two metal plates having a thickness that is an integral multiple of the pitch of the male thread 51 of 0 are butted together, a female thread 1 is formed on the center line C by tapping, and then separated into left and right sides and one of them is moved in parallel. That's fine. In order to process the thread shape of the female thread 1 of the threaded rod cutter cutting blades A and B into the special shape shown above,
There is a method of using a tap with only the effective diameter larger than the male thread 51 of the threaded rod 50, and a method of using a tap with the same effective diameter but a smaller outer diameter.
In the former method, since the effective diameter of the female thread of the cutting blade for the threaded rod cutter is large, the threads of the threaded rod 50 are plastically deformed by the cutting blades A and B for the threaded rod cutter during cutting, and the threaded rod 50 is There is a possibility that the effective diameter of the threaded rod 50 may change, and the threaded rod 50 may not be able to be smoothly screwed into a predetermined nut. On the other hand, the latter method does not have the disadvantage that the effective diameter fluctuates, but since the root diameter of the female thread 1 of the cutting blade for the threaded rod cutter is formed small, the threaded rod 50
The threaded rod cutter cutting blade A,
There is a drawback that the threaded rod 50 tends to bulge out into an elliptical shape around a portion indicated by D in FIG. 3, which is perpendicular to the direction of approach B. However, a general construction threaded rod 50
The cutting blades A and B for threaded rod cutters manufactured by the latter method are manufactured with a fine outer diameter.
In practice, the above-mentioned disadvantages rarely occur even when cutting is done by the latter method, and therefore, as cutting blades for threaded rod cutters for cutting architectural threaded rods, those manufactured by the latter method are recommended. It is preferable to use

In addition, such cutting blade A for threaded rod cutter,
If the thickness of B is an integral multiple of the pitch as described above, one side can be moved in parallel by the thickness as shown in Figure 4, and the starting position of the thread can be aligned as shown in the figure. If this is done, the cutting blades A and B for each threaded rod cutter can be made compatible, but if the female thread is directly carved into the cutter body, there is no need to consider its thickness.

(Function) As shown in FIG.
It is used by attaching the other end to a movable plate 13 which is rotated by an arm rod 11 via a link 12, and a threaded rod 50 has a female thread 1 of the same pitch as the male thread 51 of the threaded rod 50. As shown in FIGS. 1 and 2, the threaded rod 50 is sheared without crushing the threads by being sandwiched between the inner circumferential surfaces, as in the prior art. However, in the present invention, as mentioned above, the valley portion 2 is 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 50. As shown in FIG. 5, during cutting, shearing progresses with the threaded top 52 of the threaded rod 50 in contact only with the root 3.
Therefore, pressure is not applied to the side surfaces of the incomplete angled portions 4 that inevitably occur on either end face, and no screw breakage occurs in the incomplete angled portions 4.

(Effects of the invention) As is clear from the above explanation, the present invention is capable of cutting a threaded rod without crushing the threads, and also allows the top of the thread of the threaded rod to contact the bottom of the root during cutting. This prevents the screw from chipping at the incomplete chevron portion even after long-term use, so it has the advantage of being easy to manufacture and being able to be used as is in conventional threaded rod cutters. At the same time, its practical value is extremely great.

[Brief explanation of the drawing]

FIG. 1 is a central vertical sectional view showing an embodiment of the present invention;
Fig. 2 is a central vertical sectional view showing the cut state, Figs. 3 and 4 are a plan view and partially cutaway front view showing the manufacturing method, Fig. 5 is an enlarged sectional view of the main part, and Fig. 6 is FIG. 7 is an enlarged cross-sectional view of a main part showing a state of cutting by a cutting blade for a conventional threaded rod cutter. 1... Female thread, 2... Valley part, 3... Valley bottom, 50
... Threaded rod, 51 ... Male thread, 52 ... Thread top.

Claims (1)

[Scope of utility model registration request] In a cutting blade for a threaded rod cutter, which has female threads 1 of the same pitch as the male threads 51 of the threaded rod 50 carved on the inner peripheral surface in contact with the threaded rod 50 to be cut, the troughs 2 of the female threads 1 are cut into the threaded rod 50. 50, and the height of the thread of the female thread 1 is set to be wider than that of the thread of the threaded rod 5.
By making the height of the thread smaller than the height of the thread 0, the thread crest 52 of the threaded rod 50 becomes the root 3 of the female thread 1.
A cutting blade for a threaded rod cutter, characterized in that it comes into contact with.