JPH08178170A - Cold ring for gas pipe made of polyethylene - Google Patents

Abstract

PURPOSE: To eliminate a need for a high force exerted on a work and besides to perform correction of a pipe through one action of a work by a method wherein an engaging protrusion is arranged to one free end part of a half- division ring and a latch is pivotally mounted on the other free end part, and a fastening bolt is mounted on the tip of the latch. CONSTITUTION: An engaging protrusion part 11 is arranged at the end parts on one side of a pair of half-division rings 1 and 2, a latch 4 engaged with and disengaged from the engaging protrusion part 11 is pivotally mounted on the end parts on the other side, and a fastening bolt 5 is attached to the tip of the latch 4. The latch 4 is engaged with the engaging protrusion part 11 to fasten a fastening bolt 5, and pulls the free ends of both the half-vision bodies 1 and 2 this side and are brought into butt thereagainst. This constitution causes the tip of the bolt 5 to always collide with the given one point of the engaging protrusion part 11 even when the opening of a cold ring A is changed along with fastening of the bolt 5 along with fastening of the bolt 5 and dislocation of other part does not occur. Further, the fastening bolt 5 can be fastened without needing a high force.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tool, ie, a cold ring, used for straightening and restoring a squeezed-off pipe to its original shape when repairing or replacing a gas pipe made of polyethylene pipe.

[0002]

2. Description of the Related Art Generally, for repairing or replacing gas pipes made of polyethylene pipe, squeeze-off tools are used to fasten and cut the pipes on both sides of the repaired portion to repair or replace the pipes. After the replacement is completed, the tube deformed flat by the above squeeze off is corrected using a cold ring and returned to its original shape. The cold ring is formed by covering a pair of hinged half-rings on the deformed portion of the pipe, and pulling each free end in the abutting direction by using the locking means provided on the portion, thereby dividing the two half-halves. By sandwiching the pipe with a ring and applying a force from both sides of the width that spreads flat to the pipe toward the center, the shape of the pipe is restored, and the free end of the half ring is abutted. As shown in FIG. 5 and FIG. 6, the structure for pulling in the direction is such that protrusions 11 and 21 are bulged at the free ends of both half-rings 1 and 2, and one of them 11 has the other protrusion 21. It has a structure in which a lever 6 that pivotally supports a latch 4 that engages with is pivotally attached.

[0003]

The locking means of this structure engages the latch with the protrusion of the other half ring and pushes down the lever, so that the free end of the other half ring is pushed through the latch. Since it is a pulling object, it requires a very large amount of work, and it cannot be done once, and it must be gradually moved from a small deformation area to a large deformation area to gradually correct the tube. I won't. Further, in order to effectively apply the lever leverage to the latch, it is necessary to provide the lever 6 with a large handle 7 as shown in FIGS. 5 and 6 or to make the lever 6 very large. Further, since the handle bar 7 for supporting the cold ring main body A when operating the lever 6 needs to be provided so as to largely project from the rings 1 and 2, the entire size becomes considerably large. Therefore, depending on the location, it may be necessary to perform additional drilling around the pipe, and workability is poor. The present invention has been made in view of the above problems of the prior art, and the object thereof is a compact, compact type that does not require a large amount of force for work and that enables straightening of a pipe in a single work. It is to provide an inexpensive polyethylene cold pipe cold pipe.

[0004]

In order to achieve the above object, in a polyethylene gas pipe cold ring of the present invention, a hooking projection is provided on one free end of a pair of hinged half rings, and the other is A latch which is engaged with and disengaged from the engaging protrusion is rotatably pivotally attached to the free end of the latch, and a tightening bolt is attached to the tip of the latch so as to advance and retract in the length direction of the latch. The above latch prevents the extension line of the shaft center of the tightening bolt from passing through the same point on the back of the latch projection at all times, regardless of the opening degree of both halves when the latch is engaged with the latch projection. It is desirable that the shape does not exist.

[0005]

[Operation] With the cold ring configured as described above, the free ends of the two halves are mutually attached by tightening the fastening bolts by latching the latches on the engaging projections. It attracts and collides. And
Even if the opening of the cold ring changes as the bolt is tightened, the tip of the bolt always hits a predetermined point of the engaging projection and does not come off to other parts. Further, the tightening of the tightening bolt can be performed with a tool such as a ratchet wrench without requiring a large force.

[0006]

Embodiments of the present invention will be described below with reference to the drawings. In the figure, A is a cold ring body, in which a pair of half rings 1 and 2 are arranged with their inner peripheral surfaces facing each other, and a pair of opposite ends thereof are connected by a hinge 3 and the other end is opened and closed. It is freely configured.

The cold ring body A has a shape corresponding to the normal surface shape of the polyethylene gas pipe B, that is, a circular shape, when at least the inner peripheral surface of the cold ring body A is closed by abutting the free ends of both the half rings 1 and 2. It is formed, and its inner diameter corresponds approximately to the outer diameter of the polyethylene gas pipe B whose shape is to be corrected by using this cold ring. In the illustrated example, the outer peripheral surface of the cold ring body is also formed in a circular shape, but the outer peripheral surface does not necessarily have to be circular, and may be, for example, hexagonal.

Projections 11 and 21 projecting from the outer peripheral surface of the rings are erected in opposed relation to the free ends of the respective halved rings 1 and 2, and the projection 11 of one of the halved rings 1 is provided with the other. A latch 4 for engaging with and disengaging from a projection 21 (hereinafter referred to as a hooking projection) of the half ring 2 is pivotally attached.

The latch 4 is formed in a U shape, and both open ends thereof are pivotally attached to the projection 11 by a shaft 12 with the projection 11 sandwiched therebetween, and a closed tip portion is provided at the center thereof. Hole
A nut 42 is integrally fixed so as to correspond to a screw hole in 41, and a tightening bolt 5 is attached to the nut 42 by screwing a head 51 of the tightening bolt 5 toward the outside of the latch 4. The tightening bolt 5 is provided so that the extension line a of the shaft core intersects at right angles with the shaft core of the shaft 12 pivotally mounting the latch 4.

The size of the latch 4 from an arbitrary portion near the pivotal portion to the front end gradually decreases from the extension line a of the axis of the tightening bolt 5 to the lower end toward the tip of the latch 4. In the illustrated example, the upper edge is formed parallel to the line a, while the lower edge is formed as a straight line inclined upward toward the tip side. Has been done.

The latch 4 is formed in such a shape so that the tip of the bolt 5 always engages with the engaging projection regardless of the change in the opening degree of the half rings 1, 2 due to the tightening of the tightening bolt 5. The purpose of this is to prevent it from hitting a predetermined point of 21 and shifting to other parts, and as the opening degree of the cold ring body A increases, the hooking protrusion
Since the distance x connecting the upper edge of the free end of the half ring 2 including 21 and the extension line a of the axial center of the tightening bolt 5 at a right angle to the line a is uniformly reduced, the latch 4 as described above is used. Of the line a from the point near the pivotal part to the front end of
By gradually reducing the dimension from the latch 4 to the lower end of the latch 4 toward the tip side of the latch 4, the lower edge of the latch 4 is prevented from hitting the half ring 2 by the opening degree of the cold ring body A, and the shaft of the tightening bolt 5 is prevented. The extension line “a” of the lead does not always obstruct the passage of the same point on the back surface of the engaging projection 21.

The lower edge of the latch 4 does not necessarily have to be formed in a straight line as described above up to the front end of the latch 4, and a portion close to the front end is formed in an appropriate arc shape in which it is aligned with the arc of the peripheral surface of the half ring 2. However, it is also possible to form the entire lower edge of the latch 4 into a wavy shape as shown in FIG. 4, for example.

On the other hand, the engaging projection 21 is formed with a concave portion 22 at the portion where the tightening bolt 5 abuts, with which the tip of the bolt 5 engages, and the tip of the bolt 5 has a cone shape so as to easily engage with the concave portion 22. Has been formed.

In the embodiment described above, the extension line a of the shaft center of the tightening bolt 5 is arranged so as to be orthogonal to the shaft center of the shaft 12 which pivotally mounts the latch 4, but it is not always necessary to constitute such a structure. Absent. Further, instead of providing the nut 42 in the latch 4, at least the closed tip portion has a thick wall,
Of course, it is of course also possible to directly form a threaded hole in the inner peripheral surface of the latch 4.

The structure of the cold ring of the present invention is generally as described above. Explaining how to use the cold ring, first, the latch 4 is removed, and the free ends of the half rings 1, 2 are separated. The cold ring main body A was rotated to make it open, and the cold pipe main body A was opened. The gas pipe B made of polyethylene pipe was laid on the flatly deformed portion by the squeeze-off so as to wrap the portion from the flattened width direction. Then, the latch 4 is hooked on the hooking protrusion 21, the tip of the tightening bolt 5 is applied to the back surface of the hooking protrusion 21, and the hooking protrusion 21 completely strikes the other protrusion 11 using a tool such as a ratchet wrench C. The tightening bolts 5 are tightened until they come together, and the flatly deformed portion of the pipe B is removed by the movement of the cold ring body A in the closing direction accompanying the tightening of the tightening bolts 5. And pressed from both sides in the width direction below it was to correct partial to its original circular shape.

[0016]

The polyethylene gas pipe cold ring according to claim 1 uses a latch with a fastening bolt, and the polyethylene gas pipe is sandwiched between the cold rings by closing the cold ring by tightening the fastening bolt. Therefore, by using a tool such as a ratchet wrench to tighten the tightening bolt, the polyethylene gas pipe can be straightened with a small force, and even a weak person can easily work.

Further, as described above, since a large force is not required for the work, it is necessary to gradually correct the deformation from a portion having a small deformation and a relatively small force to a portion having a large deformation in several times. Instead, the correction can be completed in one operation, and the work time is greatly reduced. By the way, with the conventional cold ring, in the case of polyethylene pipe of size 50A, it takes 3 times of work and time of about 5 minutes, and size 80A.
In the case of the polyethylene pipe of No. 5, five operations and a time of about 8 minutes were required respectively, whereas in the cold ring of the present invention, it is necessary to correct it in one operation regardless of the size. It can be done and the work time is about 1 minute.

Further, the cold ring of the present invention can be obtained at a low cost and is compact because it is only necessary to improve the latch portion of the conventional cold ring.
If the excavation groove is large enough to accommodate a squeeze-off tool, the work can be sufficiently performed without the need for additional excavation. Further, since the force is applied by the linear movement of the tightening bolt, there is no place where an excessive force is applied, and the durability is excellent.

In the polyethylene gas pipe cold ring of claim 2, the shape of the latch is such that the extension line of the axial center of the tightening bolt does not always pass through the same point on the back surface of the engaging projection. While the tightening bolt is being tightened, the tip always hits a certain part of the engaging projection regardless of the opening of the cold ring, and it does not come off or slip from the engaging projection. . Therefore,
The operation is stable, and the tightening force of the tightening bolt can always be effectively applied to the ring.

[Brief description of drawings]

FIG. 1 is a plan view of a polyethylene cold pipe cold pipe according to an embodiment of the present invention.

FIG. 2 is a sectional view taken along the line (2)-(2) of FIG.

FIG. 3 is a front view showing a usage state.

FIG. 4 is a front view of another embodiment in a use state.

FIG. 5 is a plan view of a conventional polyethylene cold pipe cold pipe.

FIG. 6 is a front view of the same.

[Explanation of symbols]

A: Cold ring body 1: Half ring 2: Half ring 3: Hinge 4: Latch 5: Tightening bolt

Claims (2)

[Claims] 1. A pair of half-rings, which are hinged to each other, are provided with a hooking projection at one free end thereof, and the other free end is rotatably pivotally attached with a latch for hooking and unhooking the hooking projection. A cold ring for a polyethylene pipe, in which a tightening bolt is attached to the tip of the latch so as to move back and forth in the length direction of the latch. 2. The extension line of the axial center of the tightening bolt is always on the rear surface of the engaging projection regardless of the opening degree of both split rings when the engaging bottom is engaged with the engaging projection. The cold ring for a polyethylene gas pipe according to claim 1, wherein the cold ring has a shape that does not prevent passing through the same point.