JP2843972B2 - Universal joint integrated into a small-diameter PVC manhole - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a universal joint integrated with a small-diameter PVC manhole or the like.

[0002]

2. Description of the Related Art Concrete pipe manholes are still used on public roads since PVC pipes have been used for sewer pipes since the early 1960s. Therefore, the appearance of PVC manholes is strongly demanded.

[0003] The applicant of the present invention has developed a small-caliber manhole made of PVC in which these small-diameter masques are substantially scaled up, based on many years of experience in small-diameter PVC home sashes and small-caliber public masquerades. For example, see Japanese Utility Model Application Laid-Open No. 5-87036), and its implementation has already been provided.

[0004] By the way, even in the case of such a small-diameter manhole made of PVC, a small-diameter manhole provided with a universal joint capable of freely adjusting the direction, similarly to the small-diameter PVC square, is provided in order to cope with a deviation in the direction of the inflow / outflow pipe. There is a request.

On the other hand, a universal joint provided on a conventional small-diameter PVC square, such as a universal joint integrated with a small-diameter PVC square shown in Japanese Utility Model Publication No. 61-17093, has a shell (spherical shape) formed on the main body. The core (also referred to as an adapter) having a spherical inner and outer surface is pushed into the shell via an O-ring, and an inflow or outflow pipe is inserted into the core. The structure is such that it adheres and slides freely while sealing between the shell and the core with an O-ring.

However, such a universal joint integrated with a small-diameter PVC masque has the following problems and cannot be used immediately for a small-diameter manhole.

That is, if the main body is molded by an injection molding method, an undercut is generated in the shell, so that it is necessary to perform blow molding in addition to injection molding, which increases the number of processing steps and hinders productivity. On the other hand, if the whole is formed by the injection molding method, the mold for the shell becomes complicated and the production cost is increased.

Since the fitting groove of the O-ring is provided in the blow-molded shell, a sharp fitting groove cannot be formed, and the sealing property is impaired.

[0009] Like the various types of universal joints already proposed, since the flow surface is flattened in a sectional view, it is composed of a shell, a core, and an insertion tube. The features of the universal joint, for example, the reduction in the number of parts, are not utilized.

Accordingly, an object of the present invention is to solve the above problem and to provide a universal joint integrated with a small-diameter manhole or the like.

[0011]

SUMMARY OF THE INVENTION The gist of the present invention is as follows: 1) A manhole body made of PVC is integrally formed at the time of injection molding, and its inner peripheral surface is formed as a cylindrical surface instead of a spherical surface. A core portion flattened in a sectional view, a shell portion bulged by blow-molding one end of a connection pipe, a fitting groove provided sharply at the time of injection molding on an outer periphery of the core portion, A guide fin provided at the outer periphery of the portion during injection molding, and having a rounded tip for sliding along the inner surface of the shell portion, fitted in the fitting groove,
And a seal ring for sealing between the core and the shell. The core is formed by one-shot molding to improve the sealing performance of the seal ring and reduce the sliding resistance as a universal joint. A universal joint integrated with a small-diameter manhole made of PVC, and 2) between the tip of the core part and the base of the shell part in claim 1 and to rectify the flow of wastewater to expand the diameter. A universal joint integrated with a small-sized PVC manhole provided with a rectifying ring with a seal lip that is biased, and 3) the PVC manhole body of claim 1 or 2 is replaced with a small-diameter square body Or a universal joint integrated with a small-diameter PVC manhole or the like serving as a branch pipe main body.

[0012]

BRIEF DESCRIPTION OF THE DRAWINGS The invention will be described in more detail with reference to an embodiment shown in the accompanying drawings. 1 is an overall sectional view of a first embodiment of the present invention, FIG. 2 is an enlarged view of a main part of FIG. 1, and FIG. 3 is a sectional view of a second embodiment of the present invention.

The first embodiment is suitable for a universal joint-integrated small-diameter manhole made of PVC, which is buried at a depth of up to about 2 m on a relatively narrow public road. 100-200 PVC sewer connected to the manhole
mmφ, the inspection cylinder connected to this small-diameter manhole is 30
A size of 0 mmφ is preferred.

In FIG. 1, reference numeral 1 denotes an injection-molded PVC manhole main body. The manhole main body 1 has a connection portion 2 for an inspection tube upward, a connection portion 3 for an upstream drain pipe laterally, and A downstream-side sewer connection 4 is provided.

The inspection tube connecting portion 2 has a spout structure. However, this may be a receiving structure, a rubber ring receiving structure, or a universal joint structure.

The upstream side drain pipe connecting portion 3 has a rubber ring receiving structure. That is, a rubber ring 6 is fitted in the middle of the receiving sleeve 5, and a stopper 7 is provided at the inner end thereof. However, this is not just a socket structure,
A universal joint structure may be used.

The above structure is usually adopted for a small-diameter PVC or small-diameter manhole made of PVC. In the present embodiment, the downstream-side sewer pipe connecting portion 4 is connected to the following universal joint. 8 structure.

That is, a core portion 9 integrally formed when the manhole body 1 is formed, a shell portion 11 which is blown out from one end of a PVC connection pipe (including a long PVC pipe) 10 and swells, Fitting groove 1 provided on the outer periphery of core part 9 at the time of molding
2, a D-ring (or an O-ring) 13 as a seal ring, and a J-packing (a bellows, a so-called rectifying packing) provided between the outer end of the core 9 and the base of the shell 11. 14 that perform functions).

Therefore, in the universal joint 8 of this embodiment,
Unlike the universal joint disclosed in Japanese Utility Model Publication No. Sho 61-17093 and the universal pipe joint currently in general use, the core portion 9 is not formed separately, and the inner surface of the core portion 9 is not made spherical.
Since the core portion 9 is integrally formed when the manhole body 1 is formed, the number of parts is reduced, the productivity is improved, and the shape of the fitting groove 12 of the D ring 13 is sharpened. Combined with the double seal with the J-packing 14 that exerts a rectifying function, the sealability is not impaired, and the universal joint 8 can be configured close to the manhole body 1 to reduce the overall size. It can be convenient for inspection and cleaning.

Next, the universal joint 8 will be described in more detail. In FIG. 2, the inner peripheral surface of the core portion 9 is formed by a cylindrical surface, and is flat in a cross-sectional view. In addition, on the outer peripheral surface, from the base side, a regulating surface 15 having a cross-sectional inclination, a first fin 16,
An upward U-shaped fitting groove 12 for fitting a D ring 13 and a second fin 17 are formed.
A support projection 18 for mounting the packing 14 is provided. Since the tips of the first and second fins 16 and 17 are guides that slide along the inner surface of the shell 11, they are rounded. Further, since the fins are used as the guides, the injection molding is good and the sliding resistance is small. Then, the second fin 17 is omitted and the fitting groove 12 is formed.
May be used.

Next, the shell 11 will be described. At the opening end of the shell portion 11, a regulating portion 19 whose diameter is gradually increased outward is formed, and this regulating portion 19 comes into contact with the regulating surface 15 of the core portion 9 to form a swing angle of about 15 °. I am getting it. Further, the bulging inner surface of the shell portion 11 is formed of two spherical surfaces 20a and 20b having different radii of curvature, and the radius of curvature of the spherical surface 20a on the opening side is increased to facilitate the pushing of the core portion 9.

Next, the D ring 13 and the J packing 14
Are made of synthetic rubber such as silicon rubber, and the seal lip 21 of the J packing 14 is urged so as to expand in diameter during packing. Therefore, the seal lip 21 is always pressed against the inner surface of the base portion of the shell portion 11, and even if the connection pipe 10 provided with the shell portion 11 slides closely in a free direction within a maximum swing angle of about 15 °, the so-called seal lip 21 is so-called. Does not generate waste pool.

Next, a second embodiment of the present invention will be described. In FIG. 3, the second embodiment has a universal pipe 8 provided on a branch pipe 22, and has a branch pipe body 22a, that is, a skirt 23 of the branch pipe 22, instead of the manhole body 1.

Since the manhole body 1 of the first embodiment may be a small-diameter PVC main body, it is referred to as a small-diameter manhole and the like in this specification including the branch pipe main body.
Therefore, the universal joint 8 of this embodiment is not always applied to the downstream-side sewer connection. In addition, the universal joint 8 of the present embodiment does not need to provide the J packing 14 when a so-called filth reservoir is not formed at the connection part for a check tube or a branch pipe, and when the filth reservoir may be sacrificed. .

[0025]

According to the present invention, since the core portion which is formed by injection molding at the time of injection molding of the manhole body, the main body or the branch pipe body is integrally formed, a separate core is not required, and the number of parts in the universal joint is reduced. One-shot molding with no undercut and improved productivity.

Further, since the seal ring fitting groove is provided on the outer periphery of the core portion, the seal ring is provided at the time of injection molding of the core portion, and as a result, it becomes a sharp fitting groove and does not impair the sealing performance of the seal ring. In addition, the present invention can be applied to a seal ring having any cross section.

Further, the shell portion is formed by simply bulging one end of the connection pipe by blow molding. The inner portion slides on the outer surface of the core portion with a rounded tip provided at the time of injection molding. Since the guide fins are used, they exhibit a special effect of reducing sliding resistance as a universal joint. In addition, no sewage remains even when the universal joint is slid by the rectifying ring biased to expand the diameter.

[Brief description of the drawings]

FIG. 1 is an overall sectional view of a first embodiment of the present invention.

FIG. 2 is an enlarged view of a main part of FIG.

FIG. 3 is a sectional view of a second embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Manhole main body, 8 ... Universal joint, 9 ... Core part, 11
... shell part, 12 ... fitting groove, 13 ... D-ring

Claims (3)

(57) [Claims] 1. A cylindrical manhole body which is formed integrally during injection molding of a PVC manhole body and whose inner peripheral surface is not spherical.
A core part formed in and flattened in cross-sectional view, and a shell part swelled by blow molding one end of the connection pipe,
The outer periphery of the core portion, and a fitting groove provided on the sharp injection molding, provided during injection molding to the outer periphery of the core portion,
And a roundness for sliding along the inner surface of the shell portion.
A guide fin having a distal end, fitted to the fitting groove, and a seal ring for sealing between the core portion and the shell portion, form structure from the core portion and one shot molding, C
The sealability is improved by the universal ring and the universal joint
A universal joint integrated with a small-diameter PVC manhole with reduced sliding resistance . 2. An expansion device for rectifying the flow of sewage between a front end of a core part and a base part of a shell part according to claim 1.
A universal joint that is integrated with a small-diameter PVC manhole that has a rectifying ring with a seal lip that is urged to diameter . 3. A universal joint in which the PVC manhole body according to claim 1 or 2 is integrated with a small-diameter PVC manhole or the like, which is a small-diameter square body or a branch pipe main body.