JP7219628B2 - mouthpiece - Google Patents

Description

TECHNICAL FIELD The present invention relates to a die attached to an extrusion molding apparatus for extrusion molding a hollow molded body.

Conventionally, an extrusion molding apparatus is known as an apparatus for molding a hollow molded body (hereinafter abbreviated as a hollow molded body) that is used as a material for hollow molded products such as hoses and weather strips (for example, patent documents 1). A die having an extrusion port having a shape similar to the cross-sectional shape of the hollow molded body is attached to the tip of the extrusion molding device. The raw material before molding is molded into a hollow molded body by passing through this extrusion port during extrusion.

In addition, in the hollow molded body described in Patent Document 1, since the shape-retaining member that crosses the hollow portion in the diametrical direction in the cross section extends in the longitudinal direction, the hollow molded body is not crushed or wrinkled. is prevented.

JP-A-2000-127864

By the way, when the extrusion molding apparatus described above is used, the shape of the hollow molded body is maintained by the shape retaining member traversing the inside of the hollow portion, but there are many cases where the shape retaining member cannot be formed in the hollow portion. can.

In such a case, in order to prevent the cross-sectional shape of the hollow molded body from becoming unstable, the hollow molded body is extruded from the die while gas is fed into the inside of the hollow molded body to inflate it so that the cross-sectional shape matches the shape of the extrusion port. A technique called extrusion blow molding is used for finishing.

However, in such extrusion blow molding, when it is desired to replace the pump for feeding the fluid into the hollow molded body, there is a problem that it is difficult to replace the nozzle of the pump during molding of the hollow molded body.

SUMMARY OF THE INVENTION An object of the present invention is to provide a die for an extrusion blow molding apparatus that allows easy replacement of a pump nozzle during molding of a hollow molded article while maintaining the shape of the hollow molded article. .

The base of the present invention is
A die to be attached to an extrusion molding device for extrusion molding a hollow molded body, which is a hollow molded body,
a mounting portion attached to the extrusion molding device;
an extrusion section through which the hollow molded body is extruded;
with
An annular molding space is formed in the extruding part for molding the raw material fed from the extrusion molding device into a predetermined cross-sectional shape and for extruding it to the outside as the hollow molded body,
A channel space serving as a fluid channel is continuously formed inside the mounting portion and the extrusion portion ,
In the channel space,
a connection port for detachably connecting a nozzle of an injector for injecting fluid into the channel space by frictional force ;
a blowing port provided on the inner diameter side of the molding space for blowing the fluid into the internal space of the hollow molded body;
is provided,
The connecting port and the blowing port are provided on a surface of the pushing portion opposite to the side on which the mounting portion is located.

In this way, since the connection port is formed in the mouthpiece and the nozzle is detachably connected, the nozzle of an injector such as a pump can be easily connected while maintaining the shape of the hollow molded body during extrusion blow molding. can be replaced.
In addition, since the connection port is formed on the lower surface of the extruded portion on the same side as the blow port, the nozzle can be replaced and attached/detached in a short period of time.

In addition, the base of the present invention is
The fluid is characterized by being gas or liquid.
That is, the fluid may be liquid as well as gas.

In addition, the base of the present invention is
A hollow molded product manufactured from the hollow molded body is characterized by being a sealing material.
That is, the die of the present invention is suitable for forming a sealing material.

According to the present invention, in extrusion blow molding, it is possible to provide a die for an extrusion molding apparatus that can easily change the nozzle of a pump during molding while maintaining the shape of a hollow molded body.

It is the schematic perspective view which looked at the base which concerns on embodiment from the upper direction and the downward direction. It is a figure which shows the inside of the mouthpiece which concerns on embodiment. FIG. 2 is a schematic diagram showing a situation in which the die according to the embodiment is attached to an extrusion molding device to extrude a hollow molded body. FIG. 4 is a schematic diagram showing a state of injecting fluid into the mouthpiece according to the embodiment; FIG. 2 is a diagram showing a cross section of a hollow molded body molded using the die according to the embodiment;

BEST MODE FOR CARRYING OUT THE INVENTION A mouthpiece according to an embodiment of the present invention will be described below with reference to the drawings. FIG. 1(a) is a perspective view of the base according to the embodiment as seen from above, and FIG. 1(b) is a perspective view of this as seen from below. Moreover, FIG. 2 is a figure for demonstrating the inside of a mouthpiece. As shown in FIGS. 1 and 2, the mouthpiece 2 is formed of metal such as SUS, and the mounting portion 4 attached to the extrusion molding device 26 (see FIG. 3) and the hollow molded body 24 (see FIG. 3) are extruded. It has an extrusion part 6 . In the following description, for the sake of convenience, the side of the mounting portion 4 of the mouthpiece 2 will be described as being above the mouthpiece 2 and the side of the extruding portion 6 of the mouthpiece 2 will be described as being below the mouthpiece 2 .

Here, the mounting portion 4 has an E-shape in side view, and includes an outer column portion 8, a middle column portion 10, and a connecting portion 12 that connects the outer column portion 8 and the middle column portion 10 above the mouthpiece 2. It has The extruding portion 6 has a disk shape, and its upper surface is connected to the outer column portion 8 and the middle column portion 10 .

A molding space 14 having an annular shape in plan view is formed inside the extruding portion 6 . The molding space 14 has the function of molding the raw material 32 (see FIG. 3) fed from the extrusion molding device 26 into a substantially cylindrical cross-sectional shape. The molded raw material 32 is extruded as a hollow molded body 24 .

Further, inside the attachment portion 4 and the extrusion portion 6 (inside the mouthpiece 2), an F-shaped flow passage space 16 is formed in a side view. A connection port 16a to which a nozzle 38 of a pump 36 (see FIG. 4), which is an injector for injecting fluid into the flow path space 16, is detachably connected to the end portion of the flow path space 16 on the outer column portion 8 side. is provided. At the end of the channel space 16 on the side of the central column 10, there is provided a blowing port 16b which is located on the inner diameter side of the molding space 14 and blows fluid into the internal space 40 (see FIG. 5) of the hollow molded body 24. It is The connecting port 16a and the blowing port 16b are formed on the lower surface of the push-out portion 6 (the surface opposite to the side where the mounting portion 4 is located).

The nozzle 38 may be connected to the connection port 16a by frictional force. Depending on the circumstances, the nozzle 38 may be connected to the connection port 16a. In this case, the nozzle 38 can be easily attached to and detached from the connection port 16a, and the nozzle 38 can be tightly connected to the connection port 16a.

Next, a procedure for molding the hollow molded body 24 using the die 2 according to the embodiment of the present invention will be described. FIG. 3 is a schematic diagram showing a manufacturing apparatus for manufacturing a blow-molded product. As shown in FIG. 3, the manufacturing apparatus 22 includes an extrusion molding device 26 for extrusion-molding the hollow molded article 24 and a vulcanization tank 28 for vulcanizing the hollow molded article 24 . A supply port 30 for supplying the raw material 32 of the hollow molded body 24 is formed in the body of the extrusion molding device 26, and the die 2 according to the embodiment is attached to one end of the extrusion molding device 26. ing.

Here, when manufacturing the blow-molded product 20 , first, a pump 36 shown in FIG. Next, the raw material 32 is supplied into the extrusion molding device 26 from the supply port 30 of the extrusion molding device 26 , and gas such as air is injected from the pump 36 into the flow path space 16 of the die 2 .

Next, the raw material 32 flows into the molding space 14 of the die 2 , is molded into an annular cross-sectional shape in the molding space 14 , and is extruded out of the die 2 . By continuously performing such extrusion molding, a cylindrical hollow molded body 24 extending in one direction is formed.

On the other hand, as shown in FIG. 4, the gas stored in the pump 36 is injected from the nozzle 38 into the connection port 16a. The gas sent into the channel space 16 through the connection port 16a is folded back at the connecting portion 12 and discharged from the blow port 16b. As a result, the gas is released into the internal space 40 of the hollow molded body 24 continuously extruded from the molding space 14 . Therefore, as shown in FIG. 5, the air discharged from the blowing port 16b is blown into the internal space 40 to swell the hollow molded body 24, thereby preventing the hollow molded body 24 from collapsing.

The hollow molded body 24 extruded out of the mouthpiece 2 is further continuously vulcanized in a vulcanization bath 28 and exposed to high temperatures. As a result, the viscosity of the hollow molded body 24 is lowered, and the shape is maintained in a regular state.

If the hollow molded product 20 to be completed is, for example, a sealing material such as a weatherstrip sponge, the nozzle 38 is temporarily removed from the connection port 16a, and the pump 36 in which gas such as air is stored is replaced with a liquid such as a coating agent. is replaced with another pump (not shown) in which is stored. Then, another nozzle (not shown) of another pump is connected to the connection port 16a.

The coating agent stored in another pump is injected into the channel space 16 from another nozzle through the supply port 30, passes through the channel space 16, and is discharged from the blow port 16b. Thereby, the inner space 40 of the hollow molded body 24 is coated.

Next, the hollow molded product 24 whose cross-sectional shape is maintained is cut into a predetermined length by a cutter (not shown) to complete the hollow molded product 20 . In addition, in the series of steps described above, the extrusion molding is continuously performed.

According to the invention according to this embodiment, the connection port 16a is formed in the mouthpiece 2, and the nozzle 38 is detachably connected. However, the nozzle 38 of the pump 36 can easily be replaced with another nozzle of another pump.

For this reason, as described above, it is possible to blow air into the internal space 40 to inflate the hollow molded body 24 and blow a coating agent into the internal space 40 to coat the inner periphery of the hollow molded body 24 . That is, it is easy to discharge other fluid from the blowing port 16b while the hollow molded body 24 is being molded.

Further, since the connection port 16a is formed on the same lower surface of the extruding portion 6 as the blow port 16b, the nozzle can be replaced and attached/detached in a short time.
In the above-described embodiment, the nozzle is replaced while extrusion is continued, but extrusion may be temporarily stopped and the nozzle replaced.

Further, in the above-described embodiment, the case where the hollow molded body 24 is a sealing material is exemplified, but the hollow molded body 24 may be a hose-like member.
In the above-described embodiment, the mounting portion 4 is E-shaped when viewed from the side, and the flow path space 16 is F-shaped when viewed from the side. is not necessarily limited to this.

Further, in the above-described embodiments, the fluid injected into the supply port 30 may be gas or liquid. Air, nitrogen, etc. are mentioned as gas. In addition to the coating agent, examples of the liquid include a liquid polymer containing a foaming agent and a cross-linking agent. Liquid silicone rubber or the like is assumed as the liquid polymer.

In the above-described embodiment, as an example of replacing the nozzle, the completed hollow molded product 20 is a sealing material, but the completed hollow molded product 20 does not necessarily have to be a sealing material. Instead, the nozzle can be replaced even if it is a hose. Further, the fluid discharged into the internal space 40 of the hollow molded body 24 after the replacement of the nozzle may be liquid other than the coating agent, or may be gas.

Further, in the above-described embodiment, the case where the hollow molded body 24 has a substantially cylindrical shape is illustrated, but the hollow molded body 24 is not necessarily limited to a substantially cylindrical shape as long as it has a cylindrical shape.
Further, in the above-described embodiment, a pump is used as an injector for injecting fluid into the channel space 16, but the injector may be a device other than a pump.

Moreover, in the above-described embodiment, the base 2 is not necessarily limited to metal. For example, a ceramic or the like may be used as the base.

2 Mouthpiece 4 Mounting portion 6 Extruding portion 8 Outer column portion 10 Middle column portion 12 Connecting portion 14 Molding space 16 Channel space 16a Connection port 16b Blowing port 20 Hollow molded product 22 Manufacturing device 24 Hollow molded body 26 Extrusion molding device 28 Vulcanization Tank 30 Supply port 32 Raw material 36 Pump 38 Nozzle 40 Internal space

Claims (3)

A die to be attached to an extrusion molding device for extrusion molding a hollow molded body, which is a hollow molded body,
a mounting portion attached to the extrusion molding device;
an extrusion section through which the hollow molded body is extruded;
with
An annular molding space is formed in the extruding part for molding the raw material fed from the extrusion molding device into a predetermined cross-sectional shape and for extruding it to the outside as the hollow molded body,
A channel space serving as a fluid channel is continuously formed inside the mounting portion and the extrusion portion ,
In the channel space,
a connection port for detachably connecting a nozzle of an injector for injecting fluid into the channel space by frictional force ;
a blowing port provided on the inner diameter side of the molding space for blowing the fluid into the internal space of the hollow molded body;
is provided,
The mouthpiece , wherein the connecting port and the blowing port are provided on a surface of the extruded portion opposite to the side on which the mounting portion is located. 2. The mouthpiece according to claim 1 , wherein said fluid is gas or liquid. 3. The die according to claim 1 , wherein a hollow molded product manufactured from said hollow molded body is a sealing material.

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