JPH06246359A - Wiper for pipe bender - Google Patents

Abstract

PURPOSE:TO easily and precisely perform repairing by making the inside surface of a guide, of which one end projecting from a base is of a knife edge shape, a sliding surface of a pipe, and thereby making the reusing possible if only one end of a pipe is ground. CONSTITUTION:The wiper 1 is constituted of a base 2, one side of which is provided with an attaching surface to a pipe bender, and a guide 3 which is freely attachable/detachable and also freely slidingly attachable to a recessed groove 20 provided on the other side of this base 2 and which is of a semicircular cross-section. The groove 10 to be provided in the wiper 1 is formed by the guide 3, and the pipe 4 is slidingly in contact with the inside surface of the guide 3. If a knife edge shaped one end of the guide 3 is chipped off, only one end of the guide 3 is ground and polished, the guide 3 is advanced against the base 2, and the knife edge shaped one end that is restored is made projecting from the tip end of the base 2. The grinding is necessary only for the guide 3, and the guide 3 is semicircular in the cross section so that the grinding of the outer surface of one end is easy.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wiper used for bending a pipe having a large curvature or bending a thin pipe when the pipe is bent by a pipe bender.

[0002]

2. Description of the Related Art Assuming that the diameter of a pipe is D, the radius of curvature of bending by a side bender type pipe bender is 3D.
If the pipe to be bent is a thin-walled pipe with a high void ratio, the part with the radius of curvature is generally smaller than this, and a part called a wiper is added. Then, a wrinkle is used to control the wrinkles caused by the material being compressed on the inner corner side of the bent pipe.

As shown in FIG. 3, the wiper 1 is provided with a groove portion 10 into which a pipe 4 to be bent is fitted and which serves as a sliding surface of the pipe 4. When the pipe 4 is bent by bending the pipe 4 pressed against the groove 10 in the direction of the arrow in the drawing to bend the pipe 4, the end of the knife edge wrinkles. To prevent the occurrence of. This wiper 1 is made of various materials such as iron, copper, aluminum bronze, phosphor bronze, and resin, depending on the material of the pipe 4 to be bent, but all of them are formed by cutting from solid material by machining. Has been done.

[0004]

In the wiper 1, as described above, since the wrinkle is controlled at the knife edge portion, the load applied to the knife edge portion is extremely large. Therefore, as shown in FIG. The defect 12 is likely to occur at the knife edge portion. And such a defect 1
2 occurs, scratches and wrinkles occur on the pipe 4 side. Therefore, the wiper 1 having the defect 12 is shown in FIG.
By cutting the mounting surface to the pipe bender indicated by C to the line indicated by F in the figure, the knife edge portion is restored and reused. The arc shape of the pipe bender has a semicircular cross section. Since the B surface that comes into contact with the groove is a three-dimensional curved surface, if it is hand-finished with a tool such as a sander, a high degree of skill, patience, and a great deal of time are required. Also, even if reworked in this way,
It is difficult to have the same life as a new product, and the bending of the pipe 4 tends to be poor. Of course, if a specialist is requested to perform the above-mentioned reprocessing, such problems of service life and workmanship can be cleared, but the cost and the number of days are required.

The present invention has been made in view of the above points, and an object of the present invention is to provide a wiper for a pipe bender which can easily and accurately repair a defect.

[0006]

DISCLOSURE OF THE INVENTION A wiper for a pipe bender according to the present invention comprises a base having a mounting surface for the pipe bender, and a semi-circular cross-section guide detachably attached to the base. The guide is characterized in that the inner surface of the guide, which has a knife edge at one end protruding from the base, is the sliding surface of the pipe.

[0007]

According to the present invention, it is at one end of the guide that a defect occurs, and if only one end of the guide having a semicircular cross section is ground,
Can be reused.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below with reference to the illustrated embodiments. As shown in FIG. 1, the wiper 1 is not a one-piece molded product, but a base having a mounting surface for a pipe bender on one surface side. 2 and a guide 3 having a semicircular cross section which is detachably and slidably attached to a groove 20 provided on the other surface of the base 2. The groove 10 provided on the wiper 1 is formed by the guide 3. Pipe 4 is guide 3
It shall be in sliding contact with the inner surface. And, the guide 3 whose one end has a knife edge shape by grinding the outer surface is
A support portion 30 for reinforcement and fixation is provided at the other end, and the knife edge-shaped one end side is attached to the base 2 in a state of slightly protruding from the base 2. Guide 3
Like the conventional wiper 1, the material of can be appropriately selected according to the material of the pipe 3 to be bent, and can be formed of, for example, sheet metal.

When the pipe 4 is bent by using the wiper 1, one end of the guide 3 in the shape of a knife edge controls the surface of the pipe 4 to be bent to prevent the occurrence of scratches and wrinkles. When the knife edge-shaped end of the guide 3 is lost, only one end of the guide 3 is ground and polished, and the guide 3 is advanced with respect to the base 2 to restore the restored knife edge-shaped end from the tip of the base 2. Make it protrude. Since the base 2 does not come into contact with the pipe 4, the base 2 is not damaged, and only the guide 3 needs to be ground. Moreover, since the guide 3 has a semicircular cross section, one end of the outer surface can be ground easily. Moreover, even if it is ground by hand, it has a long life and the bending of the pipe 4 does not deteriorate. Since the guide 3 in the illustrated example can be reworked by the dimension E in FIG. 1, it can be used for a very long time as long as it is reworked. Furthermore, by exchanging the guide 3, the base 2 can be used practically permanently.

[0010]

As described above, according to the present invention, the base is provided with the mounting surface for the pipe bender, and the guide having the semicircular cross section is detachably attached to the base so as to project from the base. Since the inner surface of the guide whose one end is a knife edge is the sliding surface of the pipe,
It is only at one end of the guide that the pipe may be damaged by bending, and even if the pipe is damaged, it is not necessary to grind the mounting surface of the base on the pipe bender. It can be reused by grinding only one, and the repair of defects can be performed easily and accurately.

[Brief description of drawings]

FIG. 1 shows an embodiment, (a) is a perspective view and (b) is a front view.

[Fig. 2] Fig. 2 shows the same guide as above, (a) is a side view, (b) is a side view.
Is a front view and (c) is a bottom view.

FIG. 3 shows a conventional example, and both (a) and (b) are perspective views.

FIG. 4 (a) is a perspective view showing the same defect, and FIG. 4 (b) is a side view showing a repair grinding amount.

[Explanation of symbols]

 1 Wiper 2 Base 3 Guide

Claims (3)

[Claims] 1. A guide having a base having a mounting surface for mounting on a pipe bender and a guide having a semicircular cross section removably attached to the base, and one end protruding from the base having a knife edge shape. A wiper for pipe benders, characterized in that the inner surface is the sliding surface of the pipe. 2. The wiper for a pipe bender according to claim 1, wherein the guide is slidable in the axial direction with respect to the base. 3. The wiper for a pipe bender according to claim 1, wherein the guide has a support portion for reinforcement at the other end.