JPS5822331B2 - Kanagata Souchi - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a mold for forming pipes of different diameters, and more particularly, a ring groove is formed on the inner periphery of the tip of the opening, or an annular body such as a packing engagement ring or a stopper ring is implanted. The present invention relates to a mold apparatus for forming different diameter pipes, which is configured such that the different diameter portion can be pressed and adjusted from the outer periphery by fluid pressure.

In the present invention, a pipe of different diameters refers to a long pipe or a pipe joint, etc., which has an annular groove for attaching a seal on the inner periphery of the socket, or a pipe with a seal retaining ring or a stopper ring implanted on the inner periphery of the socket. This is a general term for various types of pipes, especially tubes with different diameters formed by sleeve molding.

The open ends of headless long tubes and short tubes are heated and softened, and a deformable core is pushed into them to enlarge the diameter. At the same time, a ring groove for attaching a seal is formed on the inner periphery of the enlarged diameter portion, and a ring groove for attaching a seal is formed on the inner circumference of the enlarged diameter portion. It is well known to form pipes of different diameters such as sockets and pipe joints by implanting a combination ring or a stopper ring.

For example, Figures 1 to 4 are schematic longitudinal cross-sectional views of main parts for explaining the process of manufacturing different diameter pipes using a known mold device for forming different diameter pipes, and Figures 1 and 2 show a packing attached to the inner surface of the socket. Figures 3 and 4 show the process of forming a ring groove for the socket, and the process of implanting a seal-engaging ring on the inner surface of the socket.

That is, according to FIGS. 1 and 2, the mold device 1 includes a plurality of thrust members 3, 3.・・・・・・
Since the thrust member 3 is expanded in diameter before and after pushing the device 1 into the heat-softened resin tube 4, an annular groove is formed on the inner periphery of the expanded diameter part as shown in Fig. 2. A diameter tube is obtained.

Further, according to FIG. 3.4, the mold device 1 is constructed almost the same as in FIGS. 1 and 2, but a groove 6 for engaging the ring 5 is provided on the outer periphery of the thrust member 3. It is being

Therefore, when the ring 5 is engaged with the groove 6 and the resin tube 4 is pushed in and the thrust member 3 is expanded in the same manner as shown in FIG. A pipe with different diameters is obtained.

In such a mold for forming a pipe of different diameters, in order to accurately define the ring groove formed on the inner periphery of the socket part into a predetermined shape, or to securely implant the ring 5 on the inner periphery of the socket part, A method is adopted in which an outer mold 7 as shown in FIGS. 2 and 4 is placed on the outer periphery of the different diameter portion, and the inner and outer peripheries of the different diameter portion are precisely regulated by pressing the outer mold 7.

However, when adopting such a method, it is necessary to prepare several types of outer molds 7 with specific shapes depending on the shape of the annular groove and ring 5, and to select and use them as appropriate. It is impossible to apply it to various types of mold equipment.

Therefore, it is necessary to prepare many types of outer molds depending on the shapes of the annular grooves and rings, and the outer molds must be replaced every time these shapes are changed.

Therefore, in order to reduce the equipment cost of the entire mold equipment or simplify the work of replacing the outer mold, it is possible to create an outer mold that can be used in common for forming molds for manufacturing pipes with different diameters having many types of grooves and rings. Development of a mold is desired.

The present invention has been made with attention to the situation such as slanting, and its purpose is to form ring grooves of various shapes on the inner periphery of the open end of the tube, or to implant rings of various shapes. At times,
It is an object of the present invention to provide a mold device that can reliably press and regulate the inner and outer surfaces of the mold, and in particular, an outer mold that is effective for achieving this purpose.

Therefore, the structure of the present invention is composed of a core that regulates the inner surface shape of the tip of the opening of the tube, and an outer mold that regulates the outer shape of the tip of the opening, and the inner periphery of the outer mold is provided with tubes of different diameters. A fluid press-fitting cavity is provided on the inner periphery of the outer mold that regulates the outer periphery of the different diameter part corresponding to the annular groove forming part, the packing engagement ring, or the stopper ring implantation part, and the different diameter part is press-fitted into the cavity. The present invention relates to a mold for forming pipes of different diameters, which is configured to be press-regulated from the outer periphery by fluid pressure applied thereto.

In the mold device of the present invention, the different diameter portion is pressed and regulated by compressed fluid that is press-fitted into the cavity on the inner surface of the outer mold.

Therefore, what shape of ring groove should be placed on the inner circumference of the tube? No matter when forming or implanting a ring of any shape, the compressed fluid uniformly presses and regulates the outer periphery of the different diameter portion according to the shape.

For this reason, one outer mold can be used in common for manufacturing pipes of various shapes with different diameters, and the shape of the outer mold itself is significantly simplified.

It will be done.

The configuration and effects of the present invention will be described below based on the drawings which are examples, but the following explanations are merely illustrative of typical embodiments and are not intended to limit the present invention.

5 to 8 are longitudinal cross-sectional views of essential parts illustrating the process of forming pipes of different diameters using the mold device of the present invention, and FIGS. Figures 7 and 8 show the process of forming the irregularly shaped ring, respectively.

In the present invention, the core 8 that is pushed into the inner periphery of the resin tube 4 to be processed into a different diameter is not essentially different from the mold device as explained in FIGS. A variety of commonly used cores can be used.

However, the outer mold 7 used in the present invention has a cavity 7/
A press-fit hole 9 for press-fitting fluid into the cavity 7' is also provided.

Therefore, the core 8 is pushed into the end of the heated and softened resin tube 4,
When fluid is pressurized into the rear cavity 71 that abuts and surrounds the outer mold 7 on the outer periphery of the different diameter part of the resin tube 4, the different diameter part is compressed by the fluid pressure as shown in FIG. 6, and the inner and outer surfaces are precisely regulated. be done.

7 and 8, the outer mold 7 is provided with a cavity 7' and a press-fit hole 9, and the ring 5 is reliably implanted on the inner surface of the different diameter part by the pressure of the fluid press-fitted into the cavity 7'. will be established.

As is clear from the above diagram, in the present invention, the pressure regulation from the outer periphery of the different diameter portion is performed by fluid pressure.
Regardless of the shapes of the annular grooves and rings 5 provided in the different diameter portions, the pressure adjustment is carried out evenly according to their shapes.

That is, according to the present invention, annular grooves of various shapes can be accurately formed with one type of outer mold 7, and rings of various shapes (including, for example, the rings shown in FIGS. 3 and 4) can be formed. Can be reliably planted.

In the present invention, the shape of the cavity 7' provided on the inner surface of the outer mold 7 should not be construed as limiting, and the point is that when the outer mold 7 is closely attached to the outer periphery of the resin pipe with different diameters, the shape of the cavity 7' provided on the inner surface of the outer mold 7 is Other shapes than those illustrated can be used as long as they form voids that can compress the fluid.

Compressed air is most commonly used as the fluid to be press-fitted into the cavity 7/, but it is also possible to use hot water, cold water, etc. to cool and harden the different diameter portion at the same time as adjusting the pressure. This is particularly advantageous for small diameter pipes.

The outer mold 7 is usually divided into 2 to 4 parts in order to retreat from the outer periphery of the pipe with different diameters after pressure adjustment, but each connection part is precisely finished to prevent fluid from leaking during pressure adjustment. It goes without saying that it should be done.

Furthermore, although not shown, the present invention can be advantageously applied to a case where a stopper ring for locking the end of the insertion tube is attached to the back of the socket of the tube.

Note that when used for planting the stopper ring, it is also possible to use a normal tampin that does not have a movable part as illustrated.

The mold device of the present invention is configured in a diagonal manner, and the shapes of many types of pipes with different diameters can be reliably regulated with one outer mold. Complicated operations such as replacement can be omitted, which is extremely beneficial from the viewpoint of simplifying molding operations and reducing mold equipment costs.

Further, according to the present invention, the inner and outer surfaces of the different diameter portions can be precisely regulated according to the shape of the outer periphery of the core, and the outer periphery shape can be formed smoothly, among other advantages.

[Brief explanation of the drawing]

The drawings are for explaining the present invention, and Figs. 1 to 4 are longitudinal sectional views of main parts explaining the process of manufacturing different diameter pipes using a known mold device, and Figs. 5 to 8 are molds according to the present invention. FIG. 2 is a vertical cross-sectional view of a main part explaining a process of manufacturing a pipe with different diameters using the apparatus. 1... Mold device, 2... Collapse member, 3... Thrust member, 4... Resin pipe, 5... Ring, 6... Concave groove, 7.
...outer mold, 8...core, 7/...
・Cavity, 10...Fluid injector 1

Claims (1)

[Claims] 1 Consists of a core that is inserted into the inner surface of the tip of the opening of the tube and regulates its inner surface shape, and an outer mold that is placed on the outer circumferential surface of the tip of the opening and regulates its outer shape. In a mold device for forming a pipe of different diameters in which a ring groove is formed or an annular body such as a packing engagement ring or a stopper ring is implanted, the ring of the pipe of different diameters is formed on the inner periphery of the outer mold. A fluid press-fitting cavity is provided to cover the outer periphery of the different diameter part corresponding to the groove forming part, the packing engagement ring, or the stopper ring implantation part, and the different diameter part is press-fitted from the outer periphery by the fluid pressure press-fitted into the cavity. A mold for forming pipes of different diameters, characterized in that the mold is configured to adjust the pressure.