JPH0229353Y2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field] This invention relates to fittings, and in particular, to prevent liquid from pooling at the meeting area between the nipple end face of a fitting that includes a nipple and a sleeve and the inner circumferential surface of the hose. This is what I did.

[Conventional technology]

2. Description of the Related Art Conventionally, a fitting including a nipple and a sleeve is coupled to the end of a hose used in a liquid piping system for painting or food production.

With this joint fitting, the end portion of the hose is inserted between the nipple and the sleeve, and then the outer periphery of the sleeve is caulked to connect the hoses.

[Problem that the invention attempts to solve]

The nipple of conventional fittings is connected with the end face of the tip exposed to the inner circumferential surface of the hose, so there is a step between the inner circumferential surface of the nipple and the inner circumferential surface of the hose. part is occurring.

Therefore, when a conventional hose is used for liquid transport, when liquid flow is stopped, the liquid adhering to the stepped portion remains as it is, creating a pool of liquid.

For this reason, when using hoses for painting piping to paint different colors of paint, the remaining paint on the step part is not completely removed even if the inside of the hose is cleaned, resulting in mixing of different paints immediately after painting is restarted. Similarly, the problem of mixing of different types of foods occurred in the hoses of liquid food piping.

In addition, it is troublesome and time-consuming to clean until such a liquid pool is completely removed, which has the disadvantage of lowering work efficiency.

To prevent such liquid accumulation,
It is also possible to grind the end of the inner circumferential surface of the nipple to form a tapered surface to make the end face of the nipple thinner, but this reduces the strength of the end of the nipple and makes it difficult to tighten when crimped. This results in the disadvantage that the nipple is deformed.

This invention eliminates the above-mentioned drawbacks and can be used without reducing the strength of the end of the nipple of the fitting.
To provide a joint fitting which prevents a difference in level from occurring at a meeting part between a nipple end face and an inner circumferential surface of a hose when the hose is connected.

[Means for solving problems]

The nipple of the joint fitting of this invention has an annular protrusion formed on the radially outer side of the end portion of the outer peripheral surface, and a curved or tapered surface that expands in diameter outward in the axial direction at the end portion of the inner peripheral surface. ing.

When a hose is connected to this fitting, the inner circumferential surface of the hose is caulked with the annular protrusion of the nipple biting into it, and the inner circumferential surface of the hose intersects and meets the curved or tapered surface at the end of the nipple. ing.

[Effect]

In the joint structure of the coupling fitting and the hose of this invention, since the annular protrusion of the nipple bites into the inside of the hose, no step is created at the meeting point between the inner circumferential surface of the hose and the end portion of the nipple.

Further, since the end portion of the nipple has a thick annular projection, a predetermined strength is maintained, and the tip end portion of the nipple is not deformed when the sleeve is caulked.

〔Example〕

Examples of this invention will be described below with reference to the drawings.

FIG. 1 is a side view showing an embodiment of the joint fitting of this invention, with the upper half sectioned away.

The figure shows a state in which the hose 30 is coupled to the joint fitting 1.

In the joint fitting 1, a sleeve 20 is fitted concentrically to the outer circumferential surface of the nipple 10 with an annular space in between, and the sleeve 20 is fixed to the base portion of the nipple 10 adjacent to the large diameter portion 11. A connecting portion 2 for fastening to another hose or device is formed at one end of the fitting 1.

The outer circumferential surface of the nipple 10 is provided with grooves 12 formed at appropriate intervals in the axial direction, and the inner circumferential surface of the sleeve 20 is also provided with grooves at appropriate intervals in the axial direction. An uneven portion 22 is formed by the circumferential groove.

At the end portion of the outer peripheral surface of the nipple 10, an annular protrusion 13 is provided on the radially outer side with a sloped surface that is inclined obliquely inward in the axial direction from the outer peripheral edge of the end surface. The outer circumferential surface axially inside the annular projection 13 is formed with a gently curved surface and a tapered surface connected to the curved surface.

Further, at the end portion of the inner circumferential surface of the nipple 10, a curved surface 14 that expands in diameter outward in the axial direction is formed between a slightly axially inner side of the end surface and a slightly radially outer side of the inner circumferential edge of the end surface. There is.

The annular protrusion 13 and curved surface 14 at the ends of the outer and inner surfaces of the nipple 10 can be easily formed by cutting or enlarging the tip of the nipple 10 from the inside. can do.

The material of the nipple 10 and the sleeve 20 of the above-mentioned joint fitting 1 are both molded using appropriate metals according to their respective uses.
0 is similarly molded with a reinforcing layer interposed between an inner layer and an outer layer of rubber or synthetic resin suitable for the purpose.

When coupling the fitting 1 with the above structure and the hose 30, the end portion of the hose 30 is inserted into the annular space between the nipple 10 of the fitting 1 and the sleeve 20, and then the sleeve 20 is inserted from the outside. Apply pressure and caulk. As a result, the diameter of the sleeve 20 is reduced and the end portion of the hose 30 is compressed, so that the uneven portion 12 of the nipple 10 and the uneven portion 22 of the sleeve 20 are bitten into the inner circumferential surface and the outer circumferential surface of the hose 30, respectively. This results in a structure that ensures sufficient pull-out strength.

Furthermore, when the sleeve 20 is caulked, the annular protrusion 13 at the end of the nipple 10 bites into the inner peripheral surface of the hose 30, so the inner peripheral surface of the hose 30 intersects with the curved surface 14 at the end of the nipple 10. Since they meet, there is no difference in level between the inner peripheral surface of the hose 30 and the end surface of the nipple 10.

With the joint fitting of this invention, there is no need to make the tip of the nipple thin in order to reduce the step between the inner circumferential surface of the hose and the inner circumferential surface of the nipple, unlike conventional methods, so when the sleeve 20 is caulked, Deformation of the nipple 10 is eliminated.

FIG. 2 is a sectional view of the upper half of another embodiment of this invention showing the main parts.

In this embodiment, a sloped surface is formed to be inclined obliquely outward in the axial direction from the edge of the curved surface 14 formed at the end of the inner circumferential surface of the nipple 10, and a sloped surface is formed obliquely inwardly in the axial direction from the upper end edge of this sloped surface. An annular protrusion 13 formed by an inclined surface is provided.

Even when the annular protrusion 13 having such a shape is provided, the same effects as in the embodiment described above can be obtained.

In each of the embodiments described above, a case has been described in which a curved surface 14 is formed at the end portion of the inner peripheral surface of the nipple 10, but a tapered surface may be formed instead of the curved surface 14.

Furthermore, the shape of the annular protrusion 13 is not limited to that of the embodiment described above, and may be changed to any shape.

Further, the joint fittings in each of the above embodiments have an uneven portion on both the outer circumferential surface of the nipple and the inner circumferential surface of the sleeve; It may be provided on one or the other side, or it may not be provided on either side.

[Effect of idea]

As explained above, according to the fitting of this invention, the annular protrusion provided at the end of the outer peripheral surface of the nipple bites into the inner peripheral surface of the hose when the sleeve is caulked, and the end of the inner peripheral surface of the nipple Since a connecting structure is formed in which the inner circumferential surface of the hose intersects and meets the curved or tapered surface formed in the curved surface or tapered surface, there is no difference in level between the nipple end surface of the fitting and the inner circumferential surface of the hose. Therefore, when the hose connected to the coupling fitting of this invention is used for liquid flow and the flow is stopped, no liquid pool remains at the meeting point between the nipple end face and the inner peripheral surface of the hose. This makes it easier to clean the inside of the hose, especially when replacing two or more types of paint or food, such as for painting or liquid food, which not only eliminates the negative effects of liquid mixing, but also improves cleaning efficiency. The effort required is also simplified, and the effect of greatly improving work efficiency can be obtained.

In addition, according to this invention, the annular projection provided at the end of the nipple of the fitting compensates for the decrease in wall thickness due to the formation of a curved part or tapered surface at the end of the inner peripheral surface of the nipple. Therefore, the strength of the nipple does not decrease, resulting in a highly reliable bonding structure.

Note that this invention is not limited to the above-mentioned embodiments, and various modifications can be made within the scope of the technical idea of this invention, such as making it elbow-shaped.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional side view of the upper half of an embodiment of this invention, and FIG. 2 is a sectional view of the upper half of another embodiment of the invention. In the figure, 1 is a fitting, 10 is a nipple, 13 is an annular projection, 14 is a curved surface, 20 is a sleeve, 3
0 is a hose.

Claims (1)

[Scope of utility model registration request] In a fitting for inserting a hose into an annular space formed between a nipple and a sleeve and caulking the sleeve from the outer periphery to secure the hose, the outer circumferential surface of the end of the nipple has a part that bites into the inner circumferential surface of the hose. In addition to being provided with an annular protrusion, the inner peripheral surface of the end portion of the nipple is provided with a curved or tapered surface that expands in diameter outward in the axial direction and intersects and meets the inner peripheral surface of the hose. Fittings to be used.