JPS5937308Y2 - Tool for regulating pipe bending radius - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a tool for regulating the bending radius of a pipe made of an easily bendable material such as synthetic resin or lead.

In general, pipe bending techniques include, for example, a bending device using three rolls, a pipe protected by an annular body as described in Japanese Patent Application Laid-open No. 55-27452, and an arc-shaped pressing piece and a pair of pressing devices. It is known that a bending moment is applied to a pipe by

However, such known devices support bending moments at three points at considerable intervals along the length of the pipe, thereby bending the pipe. In the case of a pipe, when a bending moment is applied, the pipe does not bend but becomes flat.

The above tendency is particularly noticeable when bending with a small radius of curvature.

Although the above problem does not occur if the points of force application are placed at short distances in the longitudinal direction of the pipe, the short distance between the points of application requires a relatively large pressing force, and it is difficult to use known equipment. If this happens, workability will be extremely poor.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a tool for regulating the bending radius of a pipe, which has good workability and can suitably bend a pipe made of an easily bendable material without flattening the pipe.

The pipe bending radius regulating tool according to the present invention consists of at least one outer cylinder and at least one cylinder, and has stops on the inner peripheral surface near both ends of the outer cylinder or on the outer peripheral surface near both ends of the inner cylinder. The ring is fixed, and circumferential stop ring fitting grooves into which the stop ring fits are formed on the outer circumferential surface near both ends of the inner cylinder or on the inner circumferential surface near both ends of the outer cylinder. The outer cylinder and the inner cylinder are connected by the stop ring fitting into the stop ring fitting groove, and the pipe is inserted into the outer cylinder and the inner cylinder so that the bending radius of the pipe is controlled by the outer cylinder and the inner cylinder. It has become.

Therefore, the outer cylinder and the inner cylinder can be inclined axially or longitudinally by a predetermined angle and are inserted therein.

The pipes cannot be separated by more than that angle.

Therefore, whether a known bending device is used or the pipe is bent by input, the curvature of the pipe is regulated and the pipe will not be flattened.

Further, since the bending angle is regulated by the inner cylinder and the outer cylinder, workability is also good.

Since the acting force is applied to the pipe by the inner cylinder and the outer cylinder, the bending angle is reliably regulated and no unreasonable force is generated, unlike a pipe covered with an annular body.

Embodiments of the present invention will be described below with reference to the drawings.

In Fig. 1, 1 is an outer cylinder, and 2 is an inner cylinder. Stop rings 11 and 11 are respectively fixed to the inner circumferential surface near both ends of the outer cylinder 1, and stop rings 11 and 11 are fixed to the outer circumferential surface near both ends of the inner cylinder 2. Circumferential stop ring fitting grooves 21.21 into which the stop rings 11, 11 fit are formed, respectively.

The outer cylinder 1 and the inner cylinder 2 are the stop ring i of the outer cylinder 1,
, 1i are connected by fitting into the stop ring fitting grooves 21.21 of the inner cylinder 2, and in the illustrated example, five outer cylinders 1 and four inner cylinders 2 are connected.

In the outer cylinder 1゜1 at each end of the outer cylinder 1 and the inner cylinder 2 connected in this way, a tip inner cylinder 3 having a different shape from the other inner cylinders is attached to the stop ring 11 of the outer cylinder 1 and the tip. They are connected by a stop ring fitting groove 31 in the inner cylinder 3.

The inner tube 3 at the tip includes a tapered surface 32 and a stepped portion 33, the diameter of which decreases toward the tip.

In this way, the tapered surface 32 and the stepped portion 33, which become smaller in diameter as they approach the tip, are formed on the tip inner cylinder 3 to reduce the resistance when pulling out the pipe P button and this tool once buried. This is to hook the rope that is not attached to the stepped portion 33 and pull it out.

The pipe P is inserted into the outer cylinder 1 and inner cylinder 2 connected in this way, that is, into this tool, and the bending radius of the pipe P is regulated by the outer cylinder 1 button and the inner cylinder 2.

A pipe cannot be used if its bending radius R is too small due to its strength.

Next, the function of this tool will be explained.

If the inner cylinder 2' shown by the dotted line in FIG. Moving to B', point C on the inner cylinder engages with the stop ring at point C',
The required inclination angle θ can be obtained.

The bending radius of the pruning tool, and hence the bending radius R of the pipe P, is determined by the length over which the stop ring 11 can move within the stop ring fitting groove 21.

Therefore, by using this tool, the bending radius of the pipe can be regulated to a constant value.

Since the twisted stop ring fitting groove 21 is provided on the circumference of the inner cylinder 2, the bending direction of this tool is not limited.

In the illustrated example, a stop ring is fixed to the inner circumferential surface of the outer cylinder, and a stop ring fitting groove is formed on the outer circumferential surface of the inner cylinder. Alternatively, a stop ring fitting groove may be formed on the inner circumferential surface of the outer cylinder.

Further, the inner cylinder 3 at the tip is not necessarily required, and the tool of the present invention requires at least l outer cylinders 1 and one inner cylinder 2.

Materials for the outer cylinder and inner cylinder include metals such as iron, copper and its alloys, nickel and its alloys, aluminum and its alloys, non-metallic materials such as synthetic resins, rubber, and wood, as well as synthetic resin composite materials, Metal-based composite materials, wood-based composite materials, etc. can be used, but ease of production,
Synthetic resin may also be used due to its corrosion resistance.

Synthetic resins include polyethylene, which is a thermoplastic resin,
Polypropylene, vinyl chloride resin, fluororesin, polystyrene, As resin, ABS resin, ASA resin, etc., as well as thermosetting resins such as phenol resin, urea resin, epoxy resin, unsaturated polyester resin, melamine resin,
Silicone resin or the like can be used.

As the dimensional molding method, a compression molding method, a transfer molding method, an injection molding method, an extrusion molding method, a blow molding method, etc. can be adopted.

As explained above, according to the tool according to the present invention, the bending radius of the pipe can be regulated, and the occurrence of large bending stress at the bent part due to the bending radius of the pipe being too small can be prevented.
Flattening of the pipe can be reliably prevented.

[Brief explanation of the drawing]

FIG. 1 is a side view of the pipe bending radius regulating tool according to the present invention, showing the right half in cross section and the left half in plan, and FIG. 2 is an explanatory view of its operation. DESCRIPTION OF SYMBOLS 1... Outer cylinder, 11... Stop ring provided on the outer cylinder, 2... Inner cylinder, 21... Stop ring fitting groove formed in the inner cylinder, 3... Tip inner cylinder, 31 ...Stop ring fitting groove formed on the inner cylinder at the tip.

Claims (1)

[Scope of utility model registration request] Consisting of at least one outer cylinder and at least one inner cylinder, stop rings are fixed to the inner circumferential surface near both ends of the outer cylinder and the outer circumferential surface near both ends of the inner cylinder. Circumferential stop ring fitting grooves into which the stop ring fits are formed on the outer circumferential surface near both ends or the inner circumferential surface near both ends of the outer cylinder, and the outer cylinder and the inner cylinder are arranged so that the stop ring is connected to the stop ring. A tool for regulating the bending radius of a pipe, which is connected by fitting into a fitting groove, inserting the pipe into an outer cylinder and an inner cylinder, and regulating the bending radius of the pipe by the outer cylinder and the inner cylinder.