JP2001304487A - Anticorrosion sleeve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sleeve of such a structure as capable of maintaining the anti-corrosive effect certainly through a relatively simple procedure. SOLUTION: The anti-corrosive sleeve consists of a resin sleeve approximately in a cylindrical shape and a metal sleeve to be tightly inserted to the bore of the resin sleeve, wherein the resin sleeve has a large diametric inside surface and a small diametric inside surface one after the other in the inserting direction while the metal sleeve has a large diametric outside surface, intermediate outside surface, and a small diametric outside surface one after another in the inserting direction. The heights of the resin sleeve large diametric inside surface and the metal sleeve intermediate outside surface and small diametric outside surface are made identical to the resin sleeve small diametric inside surface and the metal sleeve large diametric outside surface, respectively. The metal sleeve is made of stainless steel, while the resin sleeve is made of a hard synthetic resin.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure of an anticorrosion sleeve for preventing corrosion of a metal exposed when a metal pipe such as a water main pipe is opened.

[0002]

Conventionally, when a branch pipe is provided in a water main pipe or the like, there is known a technique of first opening a main pipe and then closely inserting a sleeve to prevent corrosion of the peripheral surface of the opening. is there. For example, the applicant has already disclosed an anticorrosion sleeve as described in Japanese Utility Model Laid-Open No. Hei 7-23892. Incidentally, the anticorrosion sleeve is a combination of a metal sleeve and an elastic sleeve, but the cross-sectional shape of the metal sleeve is complicated to make close contact. Therefore, the manufacturing cost is high, and a large force is required at the time of deformation or withdrawal of the diameter-expanding device to expand the diameter of the metal portion.
Further, when a slight gap is formed between the metal sleeve and the water hole and the perforated hole in the more conventional structure, there is a problem that rust bumps are generated at that portion.

[0003] On the other hand, a close contact sleeve made of rubber is also known in the past, but in this case, if it is too strong when driven into an opening, the rubber will buckle and a construction failure will occur. In addition, since the perforations are not generally smooth surfaces, if the rubber is driven in contact with sharp points, the rubber surface is cut off, and a sufficient anticorrosion effect may not be expected.

An object of the present invention is to solve the above-mentioned conventional problems, and an object of the present invention is to disclose a sleeve having a structure capable of reliably maintaining an anticorrosion effect by relatively simple construction.

[0005]

In order to achieve the above object, the present invention has a double structure comprising a substantially cylindrical resin sleeve and a metal sleeve which is densely inserted into the inner periphery of the resin sleeve. The resin sleeve has a large-diameter inner circumference and a small-diameter inner circumference in order with respect to the insertion direction, and the metal sleeve has a large-diameter outer circumference, an intermediate outer circumference, and a small-diameter outer circumference in order with respect to the insertion direction. Means is used in which the height of the middle circumference and the outer circumference of the small diameter of the metal sleeve and the height of the small diameter inner circumference of the resin sleeve and the height of the large diameter outer circumference of the metal sleeve match. The metal sleeve has a function of securing rigidity as the sleeve. In addition, the resin sleeve has a function of ensuring adhesion to an opening formed in the water main. Then, the resin sleeve is expanded by completely mounting the metal sleeve, thereby bringing the sleeve into close contact with the opening of the main pipe.

[0006] By making the metal sleeve made of stainless steel, reliable corrosion protection is maintained. In addition, by adopting a hard synthetic resin for the resin sleeve, appropriate deformability and hardness are ensured.

[0007]

Preferred embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 1 shows the entirety of a metal sleeve forming a part of the anticorrosion sleeve of the present invention. A cylindrical metal sleeve 1 has an inner peripheral surface 2 which is accurately cylindrical, while an outer peripheral surface 3 has an insertion base end. Steps are provided in order from the side and narrowed down to three steps. Here, numbers 3a, 3b, and 3c are assigned in order from the maximum outer diameter. A flange 4 is provided on the base end side. The metal material must be a material that achieves the object of the present invention, and a material such as stainless steel having high anticorrosion properties is employed.

FIG. 2 shows the entire resin sleeve 5 located outside the metal sleeve 1. The outer peripheral surface 6 is composed of a large-diameter outer periphery 6a and a small-diameter outer periphery 6b, and the inner peripheral surface 7 is also large. It comprises a diameter inner circumference 7a and a small diameter inner circumference 7b. And
By driving the metal sleeve 1 inside the resin sleeve 5, the anticorrosion sleeve of the present invention is constituted. The step formed by the large-diameter outer periphery 6a and the small-diameter outer periphery 6b is a positioning step when the resin sleeve 5 is inserted into the water main.

FIG. 3 shows an opening 11 provided in the water main 10.
A jig J is used to insert the anticorrosion sleeve. First, a resin sleeve 5 and a metal sleeve 1 are combined in a single stage in advance to form a product.
Then, the metal sleeve 1 is further pushed into the resin sleeve 5 using a jig piston or the like.
FIG. 4 shows a state in which the work is completed. In this case, three types of outer diameters are formed by three steps formed on the outer circumference of the metal sleeve, and the outer diameter and the large-diameter inner circumference 7a provided on the inner peripheral surface 7 of the resin sleeve 5 are different from each other. Small diameter inner circumference 7b
The relationship will be described. That is, as shown in FIG. 3, the height A of the outer periphery 3a of the metal sleeve and the large-diameter inner periphery 7 of the resin sleeve 5
The heights a of the metal sleeves coincide with each other, and the outer circumferences 3b and 3
c and the height b of the small diameter inner circumference 7b of the resin sleeve
Matches. Further, regarding the diameter, the large inner diameter of the resin sleeve and the outer diameter 3b in the middle of the metal sleeve are almost the same. In this state, the metal sleeve 1 is pushed into the resin sleeve 5, and in the state of the product shown in FIG. 3, the inner diameter 7a of the large diameter of the resin sleeve and the outer diameter 3b of the middle of the metal sleeve are set.
Can be easily inserted and maintained. Subsequently, if the metal sleeve 1 is further pushed in, the small-diameter inner circumference 7b of the resin sleeve becomes the middle outer circumference 3b of the metal sleeve.
And the large-diameter inner circumference 7a of the resin sleeve is expanded by the large-diameter outer circumference 3a of the metal sleeve, respectively.
Deform outward. Thus, the mounting of the anticorrosion sleeve is completed in a state where the resin sleeve and the water main pipe 10 are in close contact with each other.

When the metal sleeve 1 is sufficiently inserted into the resin sleeve 5, the flange 4 prevents further insertion.

By the way, the material of the resin sleeve 5 needs to be hard enough not to buckle even if the metal sleeve is pushed in. Further, the metal sleeve 1 needs to have elasticity or deformability that does not break when the metal sleeve 1 is pushed. For example, a hard synthetic resin such as hard polypropylene or polyethylene can be cited as an example of a suitable material. It should be noted that a soft resin or the like close to rubber is not included in the present invention because it may be cut on the perforated surface as described in the conventional problem.

[0012]

According to the present invention, since the above-mentioned structure is adopted, rigidity is ensured by the metal sleeve and adhesion is ensured by the resin sleeve, so that the anticorrosion sleeve can be securely mounted. In addition, because they are integrated in a state where they are in close contact, there is no backlash,
When the metal sleeve is pushed into the resin sleeve, the resin sleeve and the metal sleeve are previously combined in only one stage, so that it is sufficient to apply a force only to the stroke of one stage further, thereby improving workability. .

Further, since the metal portion is not previously expanded and the metal sleeve is pre-assembled with the resin sleeve as in the prior art, the use of the metal sleeve as a guide facilitates the construction without the need for a special jig. Therefore, the work can be performed without a large force even at the time of pulling out. Furthermore, since the resin sleeve is hard to some extent, it is possible to prevent buckling due to excessive driving like conventional rubber, and at the same time, the resin sleeve is not cut and broken at the edge of the perforated portion.

[Brief description of the drawings]

FIG. 1 is a partial sectional view of a metal sleeve which is a part of the anticorrosion sleeve of the present invention.

FIG. 2 is a partial sectional view of a resin sleeve which is a part of the anticorrosion sleeve of the present invention.

FIG. 3 is a diagram showing a state before the work of attaching the anticorrosion sleeve to the water main.

FIG. 4 is a diagram showing a mounting completion state of the same.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Metal sleeve 2 Inner peripheral surface 3 Outer peripheral surface 3a, 3b, 3c Step of outer peripheral surface 4 Flange 5 Resin sleeve 6 Outer peripheral surface 6a Large diameter outer periphery 6b Small diameter outer periphery 7 Inner peripheral surface 7a Large diameter inner periphery 7b Small diameter inner periphery

Claims (3)

[Claims] 1. A resin sleeve comprising a substantially cylindrical resin sleeve and a metal sleeve densely inserted through the inner periphery of the resin sleeve, wherein the resin sleeve has a large-diameter inner periphery and a small-diameter inner periphery in order in the insertion direction. The metal sleeve has a large-diameter outer periphery, an intermediate outer periphery, and a small-diameter outer periphery in order with respect to the insertion direction, and the height of the large-diameter inner periphery of the resin sleeve, the intermediate outer periphery, and the small-diameter outer periphery of the metal sleeve, and the small-diameter inner periphery of the resin sleeve. An anticorrosion sleeve characterized in that the circumference and the height of the large diameter outer circumference of the metal sleeve are matched. 2. The anticorrosion sleeve according to claim 1, wherein the metal sleeve is made of stainless steel. 3. The anticorrosion sleeve according to claim 1, wherein the resin sleeve is made of a hard synthetic resin.