JPH08320093A - How to connect plastic pipes - Google Patents

Abstract

(57) [Summary] [Purpose] The number of parts required for connection is two, which enables easier connection of plastic pipes and enables tight connection. [Structure] After a presser ring 8 provided with a split is fitted on a plastic pipe p, the plastic pipe p is inserted on an inner core portion 4 of a joint body 1 and then the presser ring 8 is inserted.
Is slid forward into the concave portion 6 between the inner core portion 4 and the cylindrical portion 5 to reduce the diameter, and the plastic pipe p is sandwiched between the inner core portion 4 and the pressing ring 8. The outer diameter of the inner core portion 4 on the tip 4a side is equal to or slightly smaller than the inner diameter of the plastic pipe p, and the inner diameter of the rear end 8a of the holding ring 8 is equal to or slightly larger than the outer diameter of the plastic pipe p. Further, a plurality of locking shoulders 4b are provided on the outer peripheral surface of the inner core portion 4, and a locking projection 8b is provided on the inner peripheral surface of the presser ring 8 in correspondence with the locking shoulders 4b. Has been.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for connecting a plastic pipe, which can reduce the number of parts required for the connection and at the same time prevent the pipe from being damaged during the connection.

[0002]

2. Description of the Related Art To connect a plastic pipe, a plastic pipe is fitted to an inner core portion of a joint body, and a split ring is fitted to the plastic pipe so that the plastic pipe can be sandwiched between the inner core portion and the inner core portion. It is known that the split ring is fastened to the plastic pipe by sliding the tightening ring fitted on the split ring with a nut or a tool.
Please refer to No. 8 publication, and the one with a tool
(See Publication No. 8).

[0003]

In the above conventional technique, the number of parts is 4 in the method of sliding the tightening ring by sliding the nut with the nut and the number of parts is 3 in the method of using the tool. In each case, the number of parts is large and the work is complicated, and the connection work is unavoidably expensive. Therefore, an object of the present invention is to provide a method for connecting a plastic pipe, which enables the pipe to be easily and tightly connected to the inner core portion of the joint body by using only the retaining ring pre-fitted on the plastic pipe. It is in.

[0004]

In order to achieve the above object, a method of connecting a plastic pipe, which is a feature of the present invention, has an inner core portion projecting from one side of a collar portion, and a root side of the inner core portion. Almost half the portion is inside the cylindrical portion, a ring-shaped recess is formed between the inner core portion and the cylindrical portion, and the outer diameter of the tip side of the inner core portion is the inner diameter of the plastic pipe to be connected. The joint body is formed to be equal or slightly smaller and has a plurality of locking shoulders projecting on the outer peripheral surface, and the inner diameter of the rear end that is the front side when connected to the joint body is the above. It is formed to be equal to or slightly larger than the outer diameter of the plastic pipe, and on the inner peripheral surface, a locking convex portion is provided corresponding to the locking shoulder portion of the inner core portion, and a split is provided. Using the presser ring,
After fitting the retaining ring to the plastic pipe, insert the plastic pipe into the inner core part, and then slide the retaining ring on the plastic pipe forward into the recess of the joint body to reduce the diameter of the plastic pipe. It is sandwiched between the inner core portion and the pressing ring.

The presser ring used in this connecting method is provided with one or more notches from the rear end or the front end part, leaving the front end or the rear end part of the presser ring in a ring shape without providing a split. What is used is
This is preferable in terms of workability in making connections, and the pressing ring can be evenly tightened.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The connection method of the present invention will be described below with reference to the accompanying drawings. 1 to 4, when connecting the plastic pipe p to the inner core portion 4 of the joint body 1 in which the male threaded pipe portion 3 is provided on one surface side of the flange portion 2 and the inner core portion 4 is projectingly provided on the other surface side thereof. The joint body 1 has a ring-shaped recess between the inner core portion 4 and the cylindrical portion 5 in which a substantially half portion on the root side of the inner core portion 4 is inside the cylindrical portion 5 integrated with the joint body 1. A structure having 6 is used.

The outer diameter of the inner core portion 4 on the tip 4a side is equal to or slightly smaller than the inner diameter of the plastic pipe p, and the inner diameter of the plastic pipe p is formed on the outer peripheral surface of the inner core portion 4. A plurality of (two in the illustrated case) locking shoulders 4 which are formed to be equal to or slightly larger than
b and 4b are projected. A male screw 7 is provided between the collar portion 2 and the cylindrical portion 5.

On the other hand, a pressing ring 8 which can clamp the plastic pipe p between the inner core portion 4 and the inner core portion 4 is separately prepared. The holding ring 8 has a rear end 8a, which is a front side when connected to the joint body 1, and has an inner diameter of a plastic pipe p.
Is formed to be equal to or slightly larger than the outer diameter of the above, and an engaging convex portion 8b is provided on the inner peripheral surface so as to correspond to the engaging shoulder portion 4b, and the tip portion is formed in a tapered shape. There is also a split 9 (see in particular FIG. 4).

Next, the connection procedure will be described. First, the pressing ring 8 is fitted to the plastic pipe p from the tip,
After that, the plastic tube p is inserted up to the base of the inner core portion 4 (step shown in FIG. 2). Next, the pressing ring 8 on the plastic pipe p is slid toward the joint body 1 side, and the tip 8c of the pressing ring 8 is fitted into the recess 6 between the inner core portion 4 and the cylindrical portion 5 (FIG. 3). Stage).

Then, the pressing ring 8 is further advanced, and by this forward movement, the pressing ring 8 is moved to the inner peripheral surface 5 of the cylindrical portion 5.
Then, the plastic pipe p is tightened on the inner core portion 4 by crimping it with a to gradually reduce the diameter, and the tip 8 of the pressing ring 8a is
The connection work is completed when c reaches the innermost portion of the recessed portion 6. When this connection is completed, if the locking projection 8b is made to face the locking shoulder 4b and the locking shoulder 4b (see FIG. 1), the connection can be made tight and the connection part The sealing effect is further increased.

When carrying out this connecting method, the tip ring 18a (or the rear end portion 19b) is formed into a ring shape as shown in FIG. 5 (or FIG. 6) instead of the holding ring 8 provided with the split 9. Leaving the rear end portion 18b (or the front end portion 19).
Presser ring 18 (19) provided with one or more notches 21 (22) from a) (four places in the figure)
Can be used. These presser rings 18 (1
If 9) is used, the problem that the pressing ring is one-sided and pushed diagonally into the recessed portion 6 of the joint body 1 is solved, and it can be tightened uniformly.

A cylindrical portion 5 is provided around the inner core portion 4.
7 instead of forming the concave portion 6 by projecting the
As shown in FIG.
A male screw 23 larger than the outer diameter of the core portion 4 may be provided, and a female screw 24a of the cylinder 24 may be screwed into the male screw 23 to form a recessed portion 25 between the inner core portion 4 and the cylinder 24. . The same members as those shown in FIG. 1 are designated by the same reference numerals and the description thereof will be omitted.

In the connection method described above, for the work from at least the stage shown in FIG. 3 in which the pressing ring 8 (or 18, 19) is slid toward the recessed portion 6 side of the joint body 1, for example, plastic is used. A split nut having a split slightly larger than the outer diameter of the pipe p is screwed into the male screw 7 of the joint body 1, and the split nut is screwed to push the presser ring 8 (or 18, 19). Move it forward, collar part 2
And the rear end edge of the pressing ring 8 (or 18, 19) can be sandwiched and tightened, for example, by using a dedicated hydraulic tightening tool (plier or the like), the pressing ring 8 (or 1
8 and 19) are advanced.

[0014]

The present invention is as described above, and the plastic tube can be firmly sandwiched between the inner core portion and the pressing ring to be tightly connected to the joint body, and of course, the connection portion is constituted. Requires only two parts, the joint body and the presser ring, so that the connection work can be simplified.

[Brief description of drawings]

FIG. 1 is a front cross-sectional view showing a connecting portion of a plastic pipe configured by implementing a connecting method of the present invention.

FIG. 2 is a front cross-sectional view showing a component portion at an initial stage of carrying out the connection method of the present invention.

FIG. 3 is a front sectional view showing a component portion at an intermediate stage where the connection method of the present invention is carried out.

4 is a perspective view of the holding ring shown in FIG. 1. FIG.

FIG. 5 is a perspective view showing a modified example of the presser ring of FIG.

FIG. 6 is a perspective view showing still another modified example of the pressing ring of FIG.

7 is a front sectional view showing a modified example of the joint body of FIG.

[Explanation of symbols]

Reference numeral 1 is a joint body, 2 is a collar portion, 4 is an inner core portion, 4a is a tip, 4b is a locking shoulder portion, 5 is a cylindrical portion, 6 is a recessed portion, 8 is a holding ring, 8a is a rear end, and 8b is an engaging portion. Stop projection, 9 split,
18 and 19 are presser rings, 18a and 19a are tip portions,
18b and 19b are rear end portions, and 21 and 22 are notches.

Claims (2)

[Claims] 1. An inner core portion is projectingly provided on one side of a flange portion, and substantially half of a root side of the inner core portion is inside a cylindrical portion, and a ring-shaped portion is formed between the inner core portion and the cylindrical portion. A concave portion is formed, and the outer diameter of the tip side of the inner core portion is formed to be equal to or slightly smaller than the inner diameter of the plastic pipe to be connected, and a plurality of locking shoulder portions are projected on the outer peripheral surface. The inner diameter of the joint body that is installed and the rear end that is the front side when connecting to this joint body is formed to be equal to or slightly larger than the outer diameter of the plastic pipe, and the inner core is formed on the inner peripheral surface. After the pressing ring is fitted to the plastic tube using the pressing ring provided with the locking convex portion corresponding to the locking shoulder portion of the section and the split is provided, the plastic tube is attached to the inner core section. , And then plastic A method for connecting a plastic pipe, characterized in that a holding ring on the pipe is slid forward into a recessed portion of the joint body to reduce the diameter, and the plastic pipe is sandwiched between the inner core portion and the holding ring. 2. The presser ring used is one in which the front end or the rear end part of the presser ring is left in a ring shape without providing a split, and one or more cuts are provided from the rear end or the front end part. Item 1. A method for connecting a plastic pipe according to item 1.